Last data update: Dec 02, 2024. (Total: 48272 publications since 2009)
Records 1-30 (of 37 Records) |
Query Trace: Addo OY[original query] |
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Comparison of venous and pooled capillary hemoglobin levels for the detection of anemia among adolescent girls
Jenkins M , Amoaful EF , Abdulai M , Quartey V , Situma R , Ofosu-Apea P , Aballo J , Demuyakor ME , Gosdin L , Mapango C , Jefferds MED , Addo OY . Front Nutr 2024 11 1360306 INTRODUCTION: Blood source is a known preanalytical factor affecting hemoglobin (Hb) concentrations, and there is evidence that capillary and venous blood may yield disparate Hb levels and anemia prevalence. However, data from adolescents are scarce. OBJECTIVE: To compare Hb and anemia prevalence measured by venous and individual pooled capillary blood among a sample of girls aged 10-19 years from 232 schools in four regions of Ghana in 2022. METHODS: Among girls who had venous blood draws, a random subsample was selected for capillary blood. Hb was measured using HemoCue® Hb-301. We used Lin's concordance correlation coefficient (CCC) to quantify the strength of the bivariate relationship between venous and capillary Hb and a paired t-test for difference in means. We used McNemar's test for discordance in anemia cases by blood source and weighted Kappa to quantify agreement by anemia severity. A multivariate generalized estimating equation was used to quantify adjusted population anemia prevalence and assess the association between blood source and predicted anemia risk. RESULTS: We found strong concordance between Hb measures (CCC = 0.86). The difference between mean venous Hb (12.8 g/dL, ± 1.1) and capillary Hb (12.9 g/dL, ± 1.2) was not significant (p = 0.26). Crude anemia prevalence by venous and capillary blood was 20.6% and 19.5%, respectively. Adjusted population anemia prevalence was 23.5% for venous blood and 22.5% for capillary (p = 0.45). Blood source was not associated with predicted anemia risk (risk ratio: 0.99, 95% CI: 0.96, 1.02). Discordance in anemia cases by blood source was not significant (McNemar p = 0.46). Weighted Kappa demonstrated moderate agreement by severity (ΔΈ = 0.67). Among those with anemia by either blood source (n = 111), 59% were identified by both sources. CONCLUSION: In Ghanaian adolescent girls, there was no difference in mean Hb, anemia prevalence, or predicted anemia risk by blood source. However, only 59% of girls with anemia by either blood source were identified as having anemia by both sources. These findings suggest that pooled capillary blood may be useful for estimating Hb and anemia at the population level, but that caution is needed when interpreting individual-level data. |
Development of a population-level dichotomous indicator of minimum dietary diversity as a proxy for micronutrient adequacy in U.S. adolescents aged 10-19 years
Jenkins M , Jefferds MED , Aburto NJ , Ramakrishnan U , Hartman TJ , Martorell R , Addo OY . J Nutr 2024 BACKGROUND: Diversity is a key component of diet quality and health, but no indicator exists for adolescents under the age of 15 years. OBJECTIVE: To establish a dichotomous indicator for population-level assessment of adolescent dietary diversity as a proxy for micronutrient adequacy. METHODS: We used the probability approach to construct mean probability of adequacy (MPA) of 11 micronutrients from 2 days of 24-hour dietary recall data from NHANES, 2007-2018. For each micronutrient, probability of adequacy was calculated using the best linear unbiased predictor of usual intake. Adolescent dietary diversity score (ADDS) was derived with a maximum score of 10 food groups. Generalized linear mixed models were used to examine associations between ADDS and MPA. Receiver operating characteristic analysis was used to establish a cutoff for minimum dietary diversity for adolescents (MDD-A), using an energy-adjusted logistic model with ADDS predicting MPA > 0.6. RESULTS: Probability of adequacy was greater than 80% for all nutrients except vitamin C (42.1%), folate (65.7%), and calcium (23.8%). Population MPA was 79.4%, and nearly 92% of adolescents had an MPA > 0.6. ADDS was positively associated with MPA, and energy was a significant confounder. Area under the curve was > 0.8 on both days with sensitivity and specificity ranging from 0.71-0.80. The MDD-A cutoff was calculated as 5.12 and 5.10 food groups on day 1 and 2, respectively. CONCLUSIONS: In U.S. adolescents, the best cutoff for a dichotomous indicator of dietary diversity as a proxy for micronutrient adequacy is 6 food groups in a given day. Future research could validate MDD-A and its associated cutoff for use across country contexts. |
The Centers for Disease Control and Prevention does not recommend race-adjusted thresholds to define anemia
Jefferds MED , Addo OY , Scanlon KS , Cogswell ME , Brittenham GM , Mei Z . Am J Clin Nutr 2024 119 (1) 232-233 We read with interest the article by Kang et al. [1], “Hemoglobin distributions and prevalence of anemia in a multiethnic United States pregnant population,” as well as the accompanying Editorial by Merz and Achebe [2], “Iron deficiency in pregnancy: a health inequity [2].” Both Kang et al. [1] and Merz and Achebe [2] incorrectly stated that the Centers for Disease Control and Prevention (CDC) recommend use of lower race-adjusted thresholds to define anemia for Black individuals. The CDC does not recommend separate diagnostic thresholds to define anemia for Black individuals or any other race/ethnic group. Here, we clarify misinterpretations in recent American Journal of Clinical Nutrition publications regarding the CDC anemia threshold recommendations. | | The 1998 “Recommendations to prevent and control iron deficiency in the United States” [3], the most recent CDC publication providing guidance on thresholds to define anemia in individuals, did not recommend race-specific cutoff values for anemia. The 1998 recommendations included criteria for anemia threshold adjustments based on age, sex, pregnancy status, gestational age, altitude, and smoking status [3]. To guide the development of these 1998 CDC recommendations, the CDC requested that the Institute of Medicine (IOM) convene an expert committee to develop recommendations for preventing, detecting, and treating iron deficiency anemia among children and women of reproductive age in United States. The IOM report published in 1993 [4] is independent and not an official institutional CDC/federal recommendations publication. The 1998 CDC recommendations considered inputs from the IOM report [4], conclusions of a CDC expert panel convened in April 1994, and from other multidisciplinary subject matter experts [3]. |
Impact of anthropometry training and feasibility of 3D imaging on anthropometry data quality among children under five years in a postmortem setting
Gupta PM , Sivalogan K , Oliech R , Alexander E , Klein J , Addo OY , Gethi D , Akelo V , Blau DM , Suchdev PS . PLoS One 2023 18 (9) e0292046 BACKGROUND: The Child Health and Mortality Prevention Surveillance Network (CHAMPS) identifies causes of under-5 mortality in high mortality countries. OBJECTIVE: To address challenges in postmortem nutritional assessment, we evaluated the impact of anthropometry training and the feasibility of 3D imaging on data quality within the CHAMPS Kenya site. DESIGN: Staff were trained using World Health Organization (WHO)-recommended manual anthropometry equipment and novel 3D imaging methods to collect postmortem measurements. Following training, 76 deceased children were measured in duplicate and were compared to measurements of 75 pre-training deceased children. Outcomes included measures of data quality (standard deviations of anthropometric indices and digit preference scores (DPS)), precision (absolute and relative technical errors of measurement, TEMs or rTEMs), and accuracy (Bland-Altman plots). WHO growth standards were used to produce anthropometric indices. Post-training surveys and in-depth interviews collected qualitative feedback on measurer experience with performing manual anthropometry and ease of using 3D imaging software. RESULTS: Manual anthropometry data quality improved after training, as indicated by DPS. Standard deviations of anthropometric indices exceeded limits for high data quality when using the WHO growth standards. Reliability of measurements post-training was high as indicated by rTEMs below 1.5%. 3D imaging was highly correlated with manual measurements; however, on average 3D scans overestimated length and head circumference by 1.61 cm and 2.27 cm, respectively. Site staff preferred manual anthropometry to 3D imaging, as the imaging technology required adequate lighting and additional considerations when performing the measurements. CONCLUSIONS: Manual anthropometry was feasible and reliable postmortem in the presence of rigor mortis. 3D imaging may be an accurate alternative to manual anthropometry, but technology adjustments are needed to ensure accuracy and usability. |
Trends in micronutrient interventions, anemia, and iron deficiency among women and children in Guatemala, 2009–2019
Gosdin L , Addo OY , Palmieri M , Mesarina K , Mazariegos DI , Martínez C , Santizo MC , Guzmán L , Alfaro Y , Flores-Ayala R , Jefferds MED . Curr Dev Nutr 2023 7 (8) 101970 Background: Food fortification and micronutrient supplementation are public health strategies to improve micronutrient status in Guatemala; their population effectiveness has not been evaluated in recent years. Objective: We evaluated trends in food fortification, micronutrient supplementation, anemia, and iron deficiency among nonpregnant women aged 15–49 y [women of reproductive age (WRA)] and children 6–59 aged mo [preschool age children (PSC)]. Method: Nationally representative serial cross-sectional surveys were used to assess changes in hemoglobin, anemia, ferritin, iron deficiency, iron deficiency anemia, and self-reported consumption of fortifiable foods and micronutrient supplements during 2008/2009, 2013, 2015, 2016, 2017/2018, and 2018/2019. Predictors of hemoglobin and ferritin were assessed using generalized linear mixed models adjusted for survey year as random effects, and the consumption of fortifiable foods, supplements, and other potential confounders were fixed effects. Results: Multiple micronutrient powder consumption among PSC during the previous 3 mo was 53.3% (95% CI: 49.4, 57.2) in 2013 and 33.6% (28.8, 38.4) in 2018/2019. Anemia among PSC was 11.3% (8.0, 14.5) in 2008/2009 and 6.1% (3.6, 8.6) in 2018/2019. Anemia among WRA was 10.7% (7.2, 14.2) in 2008/2009 and 3.9% (2.7, 5.2) in 2018/2019. Iron deficiency among PSC was 15.5% (12.1, 19.0) in 2008/2009 and 10.9% (7.4, 14.5) in 2016 (lowest), but 17.1 (13.3, 21.0) in 2017/2018 (highest). Iron deficiency among WRA was 14.9% (11.6, 18.2) in 2008/2009, 13.8% (11.8, 15.8) in 2013 (lowest), and 18.9% (16.3, 21.6) in 2017/2018 (highest). Wheat flour/bread consumption was positively associated with hemoglobin among PSC, and sugar consumption was positively associated with hemoglobin among WRA. The reported consumption of fortifiable foods was not associated with ferritin among PSC or WRA. Conclusions: Guatemala has implemented multiple food fortification strategies, and anemia has declined. Increases in iron deficiency in 2017–2019 warrant further attention. Secular trends toward poverty alleviation, education, and development might be responsible for changes not explained by the micronutrient interventions evaluated. © 2023 |
Trends in micronutrient interventions, anemia, and iron deficiency among women and children in Guatemala, 2009-2019
Gosdin L , Addo OY , Palmieri M , Mesarina K , Mazariegos DI , Martnez C , Santizo MC , Guzmn L , Alfaro Y , Flores-Ayala R , Jefferds MED . Curr Dev Nutr 2023 7 (8) Background: Food fortification and micronutrient supplementation are public health strategies to improve micronutrient status in Guatemala; their population effectiveness has not been evaluated in recent years. Objective: We evaluated trends in food fortification, micronutrient supplementation, anemia, and iron deficiency among nonpregnant women aged 1549 y [women of reproductive age (WRA)] and children 659 aged mo [preschool age children (PSC)]. Method: Nationally representative serial cross-sectional surveys were used to assess changes in hemoglobin, anemia, ferritin, iron deficiency, iron deficiency anemia, and self-reported consumption of fortifiable foods and micronutrient supplements during 2008/2009, 2013, 2015, 2016, 2017/2018, and 2018/2019. Predictors of hemoglobin and ferritin were assessed using generalized linear mixed models adjusted for survey year as random effects, and the consumption of fortifiable foods, supplements, and other potential confounders were fixed effects. Results: Multiple micronutrient powder consumption among PSC during the previous 3 mo was 53.3% (95% CI: 49.4, 57.2) in 2013 and 33.6% (28.8, 38.4) in 2018/2019. Anemia among PSC was 11.3% (8.0, 14.5) in 2008/2009 and 6.1% (3.6, 8.6) in 2018/2019. Anemia among WRA was 10.7% (7.2, 14.2) in 2008/2009 and 3.9% (2.7, 5.2) in 2018/2019. Iron deficiency among PSC was 15.5% (12.1, 19.0) in 2008/2009 and 10.9% (7.4, 14.5) in 2016 (lowest), but 17.1 (13.3, 21.0) in 2017/2018 (highest). Iron deficiency among WRA was 14.9% (11.6, 18.2) in 2008/2009, 13.8% (11.8, 15.8) in 2013 (lowest), and 18.9% (16.3, 21.6) in 2017/2018 (highest). Wheat flour/bread consumption was positively associated with hemoglobin among PSC, and sugar consumption was positively associated with hemoglobin among WRA. The reported consumption of fortifiable foods was not associated with ferritin among PSC or WRA. Conclusions: Guatemala has implemented multiple food fortification strategies, and anemia has declined. Increases in iron deficiency in 20172019 warrant further attention. Secular trends toward poverty alleviation, education, and development might be responsible for changes not explained by the micronutrient interventions evaluated. 2023 |
What do United States adolescents eat? Food group consumption patterns and dietary diversity from a decade of nationally representative data
Jenkins M , Jefferds MED , Aburto NJ , Ramakrishnan U , Martorell R , Addo OY . Curr Dev Nutr 2023 7 (8) 101968 BACKGROUND: Although the importance of adolescent nutrition has gained attention in the global nutrition community, there is a gap in research focused on adolescent dietary diversity and food group consumption. OBJECTIVES: This study aimed to characterize population-level food group consumption patterns and quantify the extent of dietary diversity among United States adolescents using a large nationally representative sample of adolescents aged 10-19 y. METHODS: We used 24-h dietary recall data from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2018 to construct the 10 food groups comprising the minimum dietary diversity for women (MDD-W) indicator and estimated the prevalence of intake of each food group. A composite metric adolescent dietary diversity score (ADDS) was derived for each adolescent where 1 point was awarded per food group. Both population scores and the distribution of individual scores were estimated. Differences in proportions of food groups consumed across sociodemographic categories were tested using the Rao-Scott χ(2) test, and pairwise comparisons were expressed as population prevalence differences and prevalence ratios. RESULTS: Food group consumption patterns were very similar across 2 d of dietary recall but varied significantly by sex, race/ethnicity, and income status. The food groups with the highest prevalence of consumption were grains, white, roots, and tubers (∼99%), milk products (∼92%), and meat, poultry, and fish (∼85%), whereas <15% of adolescents consumed key micronutrient-dense foods, such as vitamin A-rich fruits and vegetables and dark green vegetables. The mean ADDS was 4.69, with modest variation across strata. CONCLUSIONS: On average, United States youth consumed fewer than 5 food groups on a given day. The lack of dietary variety and relatively low prevalence of consumption of several micronutrient-rich plant-based foods could pose a risk for adolescents' ability to achieve micronutrient adequacy in the United States. |
Streamlining micronutrient biomarker statistical analysis in populations: an introduction to the SAMBA R package
Luo H , Beal T , Blake T , Zeiler M , Geng J , Werner ER , Addo OY , Suchdev PS , Young MF . J Nutr 2023 153 (9) 2753-2761 Micronutrient deficiency is a common global health problem, and accurately assessing micronutrient biomarkers is crucial for planning and managing effective intervention programs. However, analyzing micronutrient data and applying appropriate cutoffs to define deficiencies can be challenging, particularly when considering the confounding effects of inflammation on certain micronutrient biomarkers. To address this challenge, we developed the Statistical Apparatus of Micronutrient Biomarker Analysis (SAMBA) R package, a new tool that increases ease and accessibility of population-based micronutrient biomarker analysis. The SAMBA package can analyze various micronutrient biomarkers to assess status of iron, vitamin A, zinc, and B vitamins, adjust for inflammation, account for complex survey design when appropriate, and produce reports of summary statistics and prevalence estimates of micronutrient deficiencies using recommended age- and sex-specific cutoffs. We have provided a step-by-step procedure for how to use the SAMBA R package, including how to customize it for broader use, and made both the package and user manual publicly available on GitHub. SAMBA was validated by comparing results from analyzing 24 datasets on non-pregnant women of reproductive age from 23 countries and 30 datasets on preschool-age children from 26 countries with those obtained by an independent analyst. SAMBA generated identical means, percentiles, and prevalence of micronutrient deficiencies to those calculated by the independent analyst. In conclusion, SAMBA simplifies and standardizes the process for deriving survey-weighted and inflammation-adjusted (when appropriate) estimates of the prevalence of micronutrient deficiencies, reducing the time from data cleaning to result generation. SAMBA is a valuable tool that facilitates the accurate and rapid analysis of population-based micronutrient biomarker data, which can inform public health research, programs, and policy across contexts. |
Under-recognition of measurement and management of serum ferritin among populations at high risk of iron deficiency - Authors' reply
Jefferds ME , Mei Z , Addo OY , Sharma AJ , Flores-Ayala RC , Brittenham GM . Lancet Haematol 2021 8 (11) e787-e788 We agree with Tamohiko Sato and colleagues that a paucity of ferritin measurements to detect iron deficiency in high-income, middle-income, and low-income countries restricts how well research can quantify the magnitude of the disease burden and prevent and treat the disease. Following Sato and colleagues’ suggestions, we reanalysed ferritin concentration data from the US National Health and Nutrition Examination Survey (NHANES) by age, body-mass index, and income and found no meaningful correlations. In our Article,1 we proposed a method to derive physiologically based ferritin thresholds for iron deficiency among apparently healthy young children and non-pregnant women. We concluded that this approach needs validation in non-US populations before specific threshold values are adopted. Although Sato and colleagues highlight the scarcity of ferritin data for Japan, there is also a paucity of data in the USA for populations at high risk of iron deficiency, hindering surveillance and clinical practice. NHANES measures ferritin but does not collect blood among infants younger than 12 months. Ferritin is an acute phase protein and should be adjusted for inflammation, but NHANES does not measure inflammation in all age groups consistently. Sample sizes for pregnant women are small, requiring the combining of data from approximately 10 years for dependable estimates; after 2013, NHANES stopped recording the trimester of pregnancy. The US Public Health Task Force has also emphasised the paucity of prevalence data for iron deficiency anaemia among pregnant women.2 Analysis of electronic health records for first-trimester pregnancies found that anaemia screening is virtually universal, but ferritin screening for iron deficiency is not,3 despite recommendations by the American College of Obstetrics and Gynecologists.4 We continue to search for suitable anonymised databases to examine the proposed method for deriving physiologically based thresholds for serum ferritin concentration for iron deficiency among apparently healthy individuals. Having found that some national datasets from other countries have prohibitive restrictions on their use, we welcome any suggestions of publicly available and representative ferritin data. |
Comparison of current World Health Organization guidelines with physiologically based serum ferritin thresholds for iron deficiency in healthy young children and nonpregnant women using data from the third National Health and Nutrition Examination Survey
Mei Z , Addo OY , Jefferds MED , Sharma AJ , Flores-Ayala RC , Pfeiffer CM , Brittenham GM . J Nutr 2023 153 (3) 771-780 BACKGROUND: Current WHO serum ferritin (SF) thresholds for iron deficiency (ID) in children (<12 μg/L) and women (<15 μg/L) are derived from expert opinion based on radiometric assays in use decades ago. Using a contemporary immunoturbidimetry assay, higher thresholds (children, <20 μg/L; women, <25 μg/L) were identified from physiologically based analyses. OBJECTIVE: We examined relationships of SF measured using an immunoradiometric assay from the era of expert opinion with 2 independently measured indicators of ID, hemoglobin (Hb) and erythrocyte zinc protoporphyrin (eZnPP), using data from the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994). The SF at which circulating Hb begins to decrease and eZnPP begins to increase provides a physiological basis for identifying the onset of iron-deficient erythropoiesis. METHODS: We analyzed NHANES III cross-sectional data from 2616 apparently healthy children, aged 12-59 mo, and 4639 apparently healthy nonpregnant women, aged 15-49 y. We used restricted cubic spline regression models to determine SF thresholds for ID. RESULTS: SF thresholds identified by Hb and eZnPP did not differ significantly in children, 21.2 μg/L (95% confidence interval: 18.5, 26.5) and 18.7 μg/L (17.9, 19.7), and, in women, were similar although significantly different, 24.8 μg/L (23.4, 26.9) and 22.5 μg/L (21.7, 23.3). CONCLUSIONS: These NHANES results suggest that physiologically based SF thresholds are higher than the thresholds from expert opinion established during the same era. SF thresholds found using physiological indicators detect the onset of iron-deficient erythropoiesis, whereas the WHO thresholds identify a later, more severe stage of ID. |
Experiences and lessons learned in developing and implementing a population-based nutrition and health surveillance system in Guatemala 2011-2021
Palmieri M , Flores-Ayala R , Mesarina K , Mazariegos DI , Martínez C , López B , Santizo MC , Whitehead RDJr , Addo OY , Aponte J , Quiñónez EL , Sagastume MJ , Jefferds MED . Curr Dev Nutr 2022 6 (4) nzac027 BACKGROUND: Practice-based experiences documenting development and implementation of nutrition and health surveillance systems are needed. OBJECTIVES: To describe processes, methods, and lessons learned from developing and implementing a population-based household nutrition and health surveillance system in Guatemala. METHODS: The phases and methods for the design and implementation of the surveillance system are described. Efforts to institutionalize the system in government institutions are described, and illustrative examples describing different data uses, and lessons learned are provided. RESULTS: After initial assessments of data needs and consultations with officials in government institutions and partners in the country, a population-based nutrition surveillance system prototype with complex sampling was designed and tested in 5 Guatemalan Highland departments in 2011. After dissemination of the prototype, government and partners expanded the content, and multitopic nutrition and health surveillance cycles were collected in 2013, 2015, 2016, 2017/18, and 2018/19 providing nationally representative data for households, women of reproductive age (15-49 y), and children aged 0-59 mo. For each cycle, data were to be collected from 100 clusters, 30 households in each, and 1 woman and 1 child per household. Content covered ∼25 health and nutrition topics, including coverage of all large-scale nutrition-specific interventions; the micronutrient content of fortifiable sugar, salt, and bread samples; anthropometry; and biomarkers to assess annually, or at least once, ∼25 indicators of micronutrient status and chronic disease. Data were collected by 3-5 highly trained field teams. The design was flexible and revised each cycle allowing potential changes to questionnaires, population groups, biomarkers, survey design, or other changes. Data were used to change national guidelines for vitamin A and B-12 interventions, among others, and evaluate interventions. Barriers included frequent changes of high-level government officials and heavy dependence on US funding. CONCLUSIONS: This system provides high-quality data, fills critical data gaps, and can serve as a useful model for others. |
Physiologically based serum ferritin thresholds for iron deficiency in women of reproductive age who are blood donors
Addo OY , Mei Z , Hod EA , Jefferds MED , Sharma AJ , Flores-Ayala RC , Spitalnik SL , Brittenham GM . Blood Adv 2022 6 (12) 3661-3665 Our objective is to develop a physiologically based method to determine serum ferritin thresholds for iron deficiency in healthy individuals. The current World Health Organization threshold of <15 µg/L for iron deficiency in women is based on expert opinion. We examined the relationship between serum ferritin and two independently measured indicators of iron-deficient erythropoiesis, soluble transferrin receptor (sTfR) and hemoglobin, in baseline data from 286 women, 20-49 years, who were first-time or reactivated donors in the REDS-II Donor Iron Status Evaluation (REDS-RISE) study. At lower serum ferritin concentrations, median sTfR increased as hemoglobin decreased. Using restricted cubic spline regression analysis to determine thresholds for iron-deficient erythropoiesis, the thresholds identified by sTfR (serum ferritin <25.4 µg/L) and by hemoglobin (serum ferritin <25.3 µg/L) did not differ significantly. The thresholds found in the REDS-RISE study do not differ from those identified by sTfR (serum ferritin <25.5 µg/L) and hemoglobin (serum ferritin <26.6 µg/L) in a previous study of 5,442 women, 20-49 years, in the U.S. National Health and Nutrition Examination Survey 2003-2018 (NHANES) (p=0.98 and 0.83, respectively). While international comparisons are needed, these results with US data provide additional evidence for the potential usefulness of a physiologically based method to identify serum ferritin thresholds for iron deficiency. |
Limits of detection in acute phase protein biomarkers affect inflammation correction of serum ferritin for quantifying iron status among school-age and preschool-age children and reproductive-age women
Gosdin L , Sharma AJ , Suchdev PS , Jefferds ME , Young MF , Addo OY . J Nutr 2022 152 (5) 1370-1377 BACKGROUND: Standardized practices are needed in the analysis of inflammation biomarker values outside limits of detection (LOD) when used for inflammation correction of nutritional biomarkers. OBJECTIVE: We assessed the direction and extent to which serum C-reactive protein (CRP) and alpha-1-acid-glycoprotein (AGP) values outside LODs (<0.05 mg/L and >4.0 g/L, respectively) affect inflammation regression correction of serum ferritin and compared approaches to addressing such values when estimating inflammation-adjusted ferritin and iron deficiency (ID). METHODS: Examined 29 cross-sectional datasets from 7 countries with reproductive-age women (15-49y) (n = 12,944), preschool-age children (6-59m) (n = 18,208) and school-age children (6-14y) (n = 4,625). For each dataset, we compared 6 analytic approaches for addressing CRP <LOD: listwise deletion, single imputation (lower, middle, or upper bound; LOD/√2; random number), with multiple imputation (MI). For each approach, inflammation-adjusted ferritin and ID using BRINDA regression correction were estimated. We calculated deviance of each estimate from that given by MI within each dataset and performed fixed effects multivariate meta-regression with analytic approach as moderator to compare the reliability of each approach to MI. RESULTS: Across datasets, observations outside LOD ranged from 0.0 to 35.0% of CRP values and 0.0 to 2.5% of AGP values. Pooled deviance estimates for mean ferritin (µg/L) and ID (percentage points) were: listwise deletion -0.46 (95%CI: -0.76, -0.16) and 0.14 (-0.43, 0.72), lower bound 0.45 (0.14, 0.76) and -0.36 (-0.91, 0.20), middle bound -0.21 (-0.51, 0.09) and 0.22 (-0.34, 0.79), LOD/√(2) -0.26 (-0.57, 0.04) and 0.25 (-0.31, 0.81), upper bound -0.31 (-0.61, -0.01) and 0.30 (-0.27, 0.86), and random number -0.08 (-0.38, 0.22) and 0.11 (-0.46, 0.67). There was moderation by approach in the ferritin model (p<0.001). CONCLUSIONS: Findings demonstrate the need for standardized analyses of inflammation biomarker values outside LODs and suggest that random number single imputation may be a reliable and feasible alternative to MI for CRP <LOD. |
A qualitative analysis of program fidelity and perspectives of educators and parents after two years of the girls' iron-folate tablet supplementation (GIFTS) program in Ghanaian secondary schools
Gosdin L , Amoaful EF , Sharma D , Sharma AJ , Addo OY , Ashigbi X , Mumuni B , Situma R , Ramakrishnan U , Martorell R , Jefferds ME . Curr Dev Nutr 2021 5 (7) nzab094 BACKGROUND: To address the burden of anemia in adolescent girls in Ghana, the Girls' Iron-Folate Tablet Supplementation (GIFTS) program was established in 2017. An evaluation found that although iron and folic acid (IFA) supplementation reached nearly all adolescent girls in schools during year 1, most girls received fewer than the minimum effective number of tablets over the school year. Barrier analyses highlighted schools as drivers of adherence, though information was incomplete on the reasons for the disparities among schools. Information was also lacking on the implementation of health and nutrition education. OBJECTIVES: At the start of year 3 of an integrated adolescent anemia prevention program with IFA supplementation, the present study sought to illuminate differences in program fidelity among schools and across time and potential factors that drive such differences. METHODS: After stratifying by school level, size, geographic location, and intake adherence during year 1, 16 schools were purposively selected. For each school, semistructured key informant interviews were conducted with 1 coordinator at the district level, 3 educators at the school level, and 1 parent leader. Following thematic analysis methods, recorded and transcribed interviews were coded and organized into deductive and inductive themes. RESULTS: Limited training, challenges during distribution of IFA, lack of incentives, and inconsistent health and nutrition education diminished program fidelity. Strong supply chain, widespread awareness promotion, improved acceptability, and intrinsically motivated educators improved program fidelity. After 2 y of implementation, schools had made program adaptations, and widespread changes in attitudes and beliefs about the IFA tablets had improved their acceptability. However, limitations remained related to supply chain, program ownership, communication between health and education sectors, training, motivation, and resources. CONCLUSIONS: The fidelity of Ghana's GIFTS program is strengthened by its supply chain, acceptability, and motivated stakeholders; however, training, curricula, clear communication, and incentives could improve it. |
Physiologically based serum ferritin thresholds for iron deficiency in children and non-pregnant women: A US National Health and Nutrition Examination Surveys (NHANES) serial cross-sectional study
Mei Z , Addo OY , Jefferds ME , Sharma AJ , Flores-Ayala RC , Brittenham GM . Lancet Haematol 2021 8 (8) e572-e582 BACKGROUND: Serum ferritin concentrations are the most widely used indicator for iron deficiency. WHO determined that insufficient data are available to revise the serum ferritin thresholds of less than 12 μg/L for children and less than 15 μg/L for women, which were developed on the basis of expert opinion, to define iron deficiency. We aimed to derive new physiologically based serum ferritin concentration thresholds for iron deficiency in healthy young children and non-pregnant women using data from the US National Health and Nutrition Examination Survey (NHANES). METHODS: In this serial cross-sectional study, we examined the relationship of serum ferritin with two independent indicators of iron-deficient erythropoiesis, haemoglobin and soluble transferrin receptor (sTfR), in children (12-59 months) and non-pregnant women (15-49 years) using cross-sectional NHANES data from 2003-06, 2007-10, and 2015-18. NHANES is a US national stratified multistage probability sample that includes a household interview followed by a standardised physical examination in a mobile examination centre. We excluded individuals with missing serum ferritin, sTfR, haemoglobin, or white blood cell counts measurements; non-pregnant women with missing C-reactive protein (CRP), alanine aminotransferase (ALT) or aspartate aminotransferase (AST) data were also excluded. In addition, individuals with infection (white blood cell counts >10·0×10(9)/L) and non-pregnant women with possible liver disease (ALT >70 IU/L or AST >70 IU/L) and inflammation (CRP >5·0 mg/L) were excluded. We examined distributions of haemoglobin and sTfR with serum ferritin and used restricted cubic spline regression models to determine serum ferritin thresholds for iron-deficient erythropoiesis. FINDINGS: 5964 children and 10β462 non-pregnant women had physical examinations and were screened for inclusion in the study, of whom 2569 (43·1%) children and 7498 (71·7%) non-pregnant women were included. At lower serum ferritin concentrations, median haemoglobin concentration decreased as sTfR concentration increased, with each varying in a curvilinear manner. Using restricted cubic spline plateau points to determine the onset of iron-deficient erythropoiesis, the serum ferritin thresholds identified by haemoglobin and sTfR concentrations were not different. For children, the haemoglobin identified serum ferritin threshold was 19·9 μg/L (95% CI 18·8-22·6) and the sTfR identified serum ferritin threshold was 20·0 μg/L (19·4-20·9; p=0·89). For women the haemoglobin identified serum ferritin threshold was 25·2 μg/L (24·2-26·2) and the sTfR identified serum ferritin threshold was 24·0 μg/L (23·3-24·6; p=0·05). INTERPRETATION: The association between two independent indicators of iron-deficient erythropoiesis, haemoglobin and sTfR, identified serum ferritin concentration thresholds of about 20 μg/L for children and 25 μg/L for non-pregnant women, providing physiological evidence of potential new thresholds for consideration when determining the prevalence and distribution of iron deficiency in populations. In healthy children and non-pregnant women, physiologically based thresholds for iron deficiency might be more clinically and epidemiologically relevant than those based on expert opinion. Validation of this physiologically based approach in non-US populations might help the international harmonisation of serum ferritin thresholds for iron deficiency. FUNDING: None. |
A School-Based Weekly Iron and Folic Acid Supplementation Program Effectively Reduces Anemia in a Prospective Cohort of Ghanaian Adolescent Girls
Gosdin L , Sharma AJ , Tripp K , Amoaful EF , Mahama AB , Selenje L , Jefferds ME , Martorell R , Ramakrishnan U , Addo OY . J Nutr 2021 151 (6) 1646-1655 BACKGROUND: School-based iron and folic acid (IFA) supplementation is recommended for adolescent girls in countries with high burdens of anemia. OBJECTIVES: We aimed to evaluate the context-specific effectiveness of a school-based, integrated anemia control program with IFA supplementation in Ghana. METHODS: Using data from a pre-post, longitudinal program evaluation, we evaluated the effectiveness of school-based weekly IFA supplementation in reducing the burden of anemia and increasing hemoglobin concentrations (Hb; primary outcomes) in 2 regions of Ghana. Generalized linear mixed effects models with schools (clusters) as random effects were used to quantify the change in the anemia prevalence and the mean Hb associated with cumulative IFA tablet consumption over 1 school year (30-36 weeks), controlling for participant-level potential confounders. A cut point for minimum effective cumulative IFA consumption that is reflective of adequate Hb was derived following logistic regression. This cut point was verified by a restricted cubic spline model of IFA consumption and Hb. RESULTS: The analytical sample included 60 schools and 1387 girls ages 10-19 years. The prevalence of anemia declined during 1 school year of the intervention, from 25.1% to 19.6% (P = 0.001). Students consumed a mean of 16.4 IFA tablets (range, 0-36). IFA consumption was positively associated with Hb and negatively associated with anemia. Each additional IFA tablet consumed over the school year was associated with a 5% (95% CI, 1-10%) reduction in the adjusted odds of anemia at follow-up, though the relationship is nonlinear. The cut point for minimum effective consumption was 26.7 tablets over a 30-36-week school year, with tablets provided weekly. CONCLUSIONS: School-based weekly IFA supplementation is effective in improving Hb and reducing the anemia prevalence among schoolgirls in Ghana, though most participants consumed fewer than the minimum effective number of IFA tablets. Increasing intake adherence may further improve anemia outcomes in this population. |
Association between hemoglobin and elevation among school-aged children: a verification of proposed adjustments
Kanu F , Sharma A , Addo OY , Suchdev P . Am J Clin Nutr 2023 118 (1) 114-120 Objectives: Anemia is defined by hemoglobin (Hb) lower than normal based on cutoffs specific to age and sex. Hb increases with elevation as a response to lower blood oxygen, thus adjusting Hb for elevation is necessary before applying cutoffs. Recent evidence among preschool-aged children (PSC) and reproductive-aged women (WRA) suggests current World Health Organization (WHO) recommended Hb elevation adjustments need updating. We examined the Hb and elevation association among school-age children (SAC) to confirm these findings. Methods: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project data include SAC aged 5–14 years (n = 23,454; 53.5% female) with data on Hb and elevation (−6 to 3,834 meters, m) from 6 population-based surveys from 5 countries (Columbia, Ecuador, Malawi, Mexico, United Kingdom). Anemia was defined as Hb < 115 g/L for SAC < 12 years and < 120 g/L for SAC 12–14 years after elevation adjustments. Generalized linear models were used to assess the association between Hb and elevation, including controlling for inflammation-corrected iron and vitamin A deficiency. Hb adjustments for each 500 m increase in elevation from sea level are proposed and compared to current WHO recommendations and new proposed PSC and WRA adjustments. Results: Hb was positively associated with elevation. There was no sex interaction, and the association was robust to model specification. The association among SAC and the resulting Hb adjustments were consistent with PSC and WRA findings, suggesting current WHO recommendations may under-adjust Hb at lower elevation (500–2500 m) and over-adjust Hb at higher elevation (>3000 m). Anemia prevalence in SAC using new elevation adjustments increased by 0.7 (UK) to 14.1 (Malawi) percentage points relative to current WHO elevation adjustments. Conclusions: Results confirm current WHO recommended Hb elevation adjustments may need updating, and anemia prevalence in SAC may be higher than currently estimated. Findings will inform global guidelines on use of elevation-adjusted Hb for anemia assessment and possible need for intervention among SAC. Funding Sources: Bill & Melinda Gates Foundation, Centers for Disease Control and Prevention, Eunice Kennedy Shriver National Institute of Child Health and Human Development, HarvestPlus, and United States Agency for International Development. |
Barriers to and facilitators of iron and folic acid supplementation within a school-based integrated nutrition and health promotion program among Ghanaian adolescent girls
Gosdin L , Sharma AJ , Tripp K , Amoaful EF , Mahama AB , Selenje L , Jefferds ME , Ramakrishnan U , Martorell R , Addo OY . Curr Dev Nutr 2020 4 (9) nzaa135 BACKGROUND: Anemia is a moderate public health problem among adolescent girls in Ghana. OBJECTIVES: We aimed to evaluate the barriers to and facilitators of program fidelity to a school-based anemia reduction program with weekly iron and folic acid (IFA) supplementation. METHODS: Authors analyzed directly observed weekly IFA consumption data collected longitudinally and cross-sectional data from a representative survey of 60 secondary schools and 1387 adolescent girls in the Northern and Volta regions of Ghana after 1 school year (2017-2018) of the intervention (30-36 wk). A bottleneck analysis was used to characterize the levels of IFA coverage and used adjusted generalized linear mixed-effects models to quantify the school and student drivers of IFA intake adherence. RESULTS: Of girls, 90% had ever consumed the tablet, whereas 56% had consumed ≥15 weekly tablets (mean: 16.4, range: 0-36), indicating average intake adherence was about half of the available tablets. Among ever consumers, 88% of girls liked the tablet, and 27% reported undesirable changes (primarily heavy menstrual flow). School-level factors represented 75% of the variance in IFA consumption over the school year. Total IFA tablets consumed was associated with the ability to make up missed IFA distributions (+1.4 tablets; 95% CI: +0.8, +2.0 tablets), junior compared with senior secondary school (+5.8; 95% CI: +0.1, +11.5), educators' participating in a program-related training (+7.6; 95% CI: +2.9, 12.2), and educator perceptions that implementation was difficult (-6.9; 95% CI: -12.1, -1.7) and was an excessive time burden (-4.4; 95% CI: -8.4, -0.4). CONCLUSIONS: Although the program reached Ghanaian schoolgirls, school-level factors were barriers to adherence. Modifications such as expanded training, formalized make-up IFA distributions, sensitization (awareness promotion), and additional support to senior high schools may improve adherence. Spreading the responsibility for IFA distribution to other teachers and streamlining monitoring may reduce the burden at the school level. Strengthening the health education component and improving knowledge of IFA among students may also be beneficial. |
Predictors of anaemia among adolescent schoolchildren of Ghana
Gosdin L , Tripp K , Mahama AB , Quarshie K , Amoaful EF , Selenje L , Sharma D , Jefferds ME , Sharma AJ , Whitehead RD Jr , Suchdev PS , Ramakrishnan U , Martorell R , Addo OY . J Nutr Sci 2020 9 e43 Anaemia is a public health problem in Ghana. We sought to identify factors associated with haemoglobin concentration (Hb) and anaemia among school-attending adolescents. We analysed data from 2948 adolescent girls and 609 boys (10-19 years) selected from 115 schools from regions of Ghana as a secondary analysis of baseline surveys conducted at two time-points. We measured Hb, malaria from capillary blood, anthropometry and used a modified food frequency questionnaire to assess diet. Multivariable linear and Poisson regression models were used to identify predictors of Hb and anaemia. The prevalence of anaemia, malaria and geophagy were 24, 25, and 24 %, respectively, among girls and 13, 27 and 6 %, respectively, among boys. Girls engaging in geophagy had a 53 % higher adjusted prevalence of anaemia and 0⋅39 g/dl lower Hb. There were similar results among those who tested positive for malaria (+52 % anaemia; -0⋅42 g/dl Hb). Among girls, lower anaemia prevalence and higher Hb were associated with consumption of foods rich in haeme iron (-22 %; +0⋅18 g/dl), consumption of iron-fortified cereal/beverages consumed with citrus (-50 %; +0⋅37 g/dl) and being overweight (-22 %; +0⋅22 g/dl). Age was positively associated with anaemia among girls, but negatively associated among boys. Boys who tested positive for malaria had 0⋅31 g/dl lower Hb. Boys who were overweight or had obesity and consumed flour products were also more likely to be anaemic (119 and 56 %, respectively). Factors associated with Hb and anaemia may inform anaemia reduction interventions among school-going adolescents and suggest the need to tailor them uniquely for boys and girls. |
Intraindividual double burden of overweight or obesity and micronutrient deficiencies or anemia among women of reproductive age in 17 population-based surveys
Williams AM , Guo J , Addo OY , Ismaily S , Namaste SML , Oaks BM , Rohner F , Suchdev PS , Young MF , Flores-Ayala R , Engle-Stone R . Am J Clin Nutr 2019 112 468s-477s BACKGROUND: Rising prevalence of overweight/obesity (OWOB) alongside persistent micronutrient deficiencies suggests many women face concomitant OWOB and undernutrition. OBJECTIVES: We aimed to 1) describe the prevalence of the double burden of malnutrition (DBM) among nonpregnant women of reproductive age, defined as intraindividual OWOB and either ≥1 micronutrient deficiency [micronutrient deficiency index (MDI) > 0; DBM-MDI] or anemia (DBM-anemia); 2) test whether the components of the DBM were independent; and 3) identify factors associated with DBM-MDI and DBM-anemia. METHODS: With data from 17 national surveys spanning low- and middle-income countries (LMICs) and high-income countries from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia project (n = 419 to n = 9029), we tested independence of over- and undernutrition using the Rao-Scott chi-square test and examined predictors of the DBM and its components using logistic regression for each survey. RESULTS: Median DBM-MDI was 21.9% (range: 1.6%-39.2%); median DBM-anemia was 8.6% (range: 1.0%-18.6%). OWOB and micronutrient deficiencies or anemia were independent in most surveys. Where associations existed, OWOB was negatively associated with micronutrient deficiencies and anemia in LMICs. In 1 high-income country, OWOB women were more likely to experience micronutrient deficiencies and anemia. Age was consistently positively associated with OWOB and the DBM, whereas the associations with other sociodemographic characteristics varied. Higher socioeconomic status tended to be positively associated with OWOB and the DBM in LMICs, whereas in higher-income countries the association was reversed. CONCLUSIONS: The independence of OWOB and micronutrient deficiencies or anemia within individuals suggests that these forms of over- and undernutrition may have unique etiologies. Decision-makers should still consider the prevalence, consequences, and etiology of the individual components of the DBM as programs move towards double-duty interventions aimed at addressing OWOB and undernutrition simultaneously. |
Association between anemia and household water source or sanitation in preschool children: the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project
Yu EX , Addo OY , Williams AM , Engle-Stone R , Ou J , Huang W , Guo J , Suchdev PS , Young MF . Am J Clin Nutr 2019 112 488s-497s BACKGROUND: The associations between anemia and household water source and sanitation remain unclear. OBJECTIVES: We aimed to assess the associations between anemia and household water source or sanitation in preschool children (PSC; age 6-59 mo) using population-based surveys from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project. METHODS: We analyzed national and subnational data from 21 surveys, representing 19 countries (n = 35,963). Observations with hemoglobin (Hb) and ≥1 variable reflecting household water source or sanitation were included. Anemia was defined as an altitude-adjusted Hb concentration <110 g/L. Household water source and sanitation variables were dichotomized as "improved" or "unimproved." Poisson regressions with robust variance estimates were conducted for each survey, adjusting for child sex, age, household socioeconomic status, maternal education, and type of residence. RESULTS: Access to an improved water source and improved sanitation ranged from 29.9% (Burkina Faso) to 98.4% (Bangladesh, 2012), and from 0.2% (Kenya, 2007) to 97.4% (Philippines), respectively. Prevalence of anemia ranged from 20.1% (Nicaragua) to 83.5% (Bangladesh, 2010). Seven surveys showed negative associations between anemia and improved sanitation. Three surveys showed association between anemia and improved water, with mixed directions. Meta-analyses suggested a protective association between improved household sanitation and anemia [adjusted prevalence ratio (aPR) = 0.88; 95% CI: 0.79, 0.98], and no association between improved household water and anemia (aPR = 1.00; 95% CI: 0.91, 1.10). There was heterogeneity across surveys for sanitation (P < 0.01; I2 = 66.3%) and water (P < 0.01; I2 = 55.8%). CONCLUSIONS: Although improved household sanitation was associated with reduced anemia prevalence in PSC in some surveys, this association was not consistent. Access to an improved water source in general had no association with anemia across surveys. Additional research could help clarify the heterogeneity between these conditions across countries to inform anemia reduction programs. |
Intraindividual double burden of overweight and micronutrient deficiencies or anemia among preschool children
Engle-Stone R , Guo J , Ismaily S , Addo OY , Ahmed T , Oaks B , Suchdev PS , Flores-Ayala R , Williams AM . Am J Clin Nutr 2019 112 478s-487s BACKGROUND: Child overweight prevalence is increasing globally, but micronutrient deficiencies persist. OBJECTIVES: We aimed to 1) describe the prevalence and distribution of intraindividual double burden of malnutrition (DBM), defined as coexistence of overweight or obesity (OWOB) and either micronutrient deficiencies or anemia, among preschool children; 2) assess the independence of DBM components, e.g., whether the prevalence of DBM is greater than what would be expected by chance; and 3) identify predictors of intraindividual DBM, to guide intervention targeting. METHODS: We analyzed data from 24 population-based surveys from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia project (separately by survey; n = 226 to n = 7166). We defined intraindividual DBM as coexisting OWOB and ≥1 micronutrient deficiency [e.g., Micronutrient Deficiency Index (MDI) > 0; DBM-MDI] or anemia (DBM-Anemia). We assessed independence of DBM components with the Rao-Scott chi-square test and examined predictors of DBM and its components with logistic regression. RESULTS: DBM prevalence ranged from 0% to 9.7% (median: 2.5%, DBM-MDI; 1.4%, DBM-Anemia), reflecting a lower prevalence of OWOB (range: 0%-19.5%) than of micronutrient deficiencies and anemia, which exceeded 20% in most surveys. OWOB was generally not significantly associated with micronutrient deficiencies or anemia. In more than half of surveys, children 6-23 mo of age, compared with ≥24 mo, had greater adjusted odds of DBM-Anemia, anemia, and micronutrient deficiencies. Child sex and household socioeconomic status, urban location, and caregiver education did not consistently predict DBM or its components. CONCLUSIONS: Intraindividual DBM among preschool children was low but might increase as child OWOB increases. The analysis does not support the hypothesis that DBM components cluster within individuals, suggesting that population-level DBM may be addressed by programs to reduce DBM components without targeting individuals with DBM. |
Combined infant and young child feeding with small-quantity lipid-based nutrient supplementation is associated with a reduction in anemia but no changes in anthropometric status of young children from Katanga Province of the Democratic Republic of Congo: a quasi-experimental effectiveness study
Addo OY , Locks LM , Jefferds ME , Nanama S , Albert B , Sandalinas F , Nanema A , Whitehead RD , Mei Z , Clayton HB , Garg A , Kupka R , Tripp K . Am J Clin Nutr 2020 112 (3) 683-694 BACKGROUND: Small-quantity lipid-based nutrient supplements (SQ-LNS) are efficacious in controlled settings; data are scarce on the effectiveness utilizing health care delivery platforms. OBJECTIVE: We evaluated the impact of an infant young child feeding (IYCF)-SQ-LNS intervention on anemia and growth in children aged 6-18 mo in the Democratic Republic of Congo following a quasi-experimental effectiveness design. METHODS: An intervention health zone (HZ) received enhanced IYCF including improved counseling on IYCF during pregnancy until 12 mo after birth and daily use of SQ-LNS for infants 6-12 mo; the control HZ received the standard IYCF package. We analyzed data from 2995 children, collected in repeated cross-sectional surveys. We used adjusted difference-in-difference analyses to calculate changes in anemia, iron and vitamin A deficiencies, stunting, wasting, and underweight. RESULTS: Of mothers, 70.5% received SQ-LNS at least once in the intervention HZ, with 99.6% of their children consuming SQ-LNS at least once. The mean number of batches of SQ-LNS (28 sachets per batch, 6 batches total) received was 2.3 ± 0.8 (i.e., 64.4 ± 22.4 d of SQ-LNS). The enhanced program was associated with an 11.0% point (95% CI: -18.1, -3.8; P < 0.01) adjusted relative reduction in anemia prevalence and a mean +0.26-g/dL (95% CI: 0.04, 0.48; P = 0.02) increase in hemoglobin but no effect on anthropometry or iron or vitamin A deficiencies. At endline in the intervention HZ, children aged 8-13 mo who received ≥3 monthly SQ-LNS batch distributions had higher anthropometry z scores [length-for-age z score (LAZ): +0.40, P = 0.04; weight-for-age z score (WAZ): +0.37, P = 0.04] and hemoglobin (+0.65 g/dL, P = 0.007) and a lower adjusted prevalence difference of stunting (-16.7%, P = 0.03) compared with those who received none. CONCLUSIONS: The enhanced IYCF-SQ-LNS intervention using the existing health care delivery platform was associated with a reduction in prevalence of anemia and improvement in mean hemoglobin. At endline among the subpopulation receiving ≥3 mo of SQ-LNS, their LAZ, WAZ, and hemoglobin improved. Future research could explore contextual tools to maximize coverage and intake adherence in programs using SQ-LNS. |
Prevalence and predictors of high blood pressure among women of reproductive age and children aged 10 to 14 years in Guatemala
Pickens CM , Flores-Ayala R , Addo OY , Whitehead RD Jr , Palmieri M , Ramirez-Zea M , Hong Y , Jefferds ME . Prev Chronic Dis 2020 17 E66 INTRODUCTION: Data on the prevalence and predictors of high blood pressure among children and non-pregnant women of reproductive age are sparse in Guatemala. Our objective was to identify the prevalence and predictors of high blood pressure among women of reproductive age and children in Guatemala. METHODS: We analyzed data on blood pressure among 560 children aged 10 to 14 years and 1,182 non-pregnant women aged 15 to 49 from a cross-sectional, nationally representative household survey, SIVESNU (Sistema de Vigilancia Epidemiológica de Salud y Nutrición). We defined high blood pressure among children by using 2004 and 2017 US pediatric guidelines. We defined high blood pressure among women by using 1999 World Health Organization (WHO) and 2017 American College of Cardiology/American Heart Association (ACC/AHA) guidelines. We used multivariable logistic regression to identify significant predictors of high blood pressure. A base model included key covariates (age, ethnicity, socioeconomic index, anthropometric indicators) and accounted for complex sampling. We used backward elimination to identify additional candidate predictor variables. RESULTS: High blood pressure was prevalent among 8.0% (95% confidence interval [CI], 5.4%-10.7%) and 14.0% (95% CI, 10.6%-17.5%) of children using 2004 and 2017 guidelines, respectively; and among 12.7% (95% CI, 10.7%-14.8%) and 41.1% (95% CI, 37.7%-44.4%) of women using 1999 WHO and 2017 ACC/AHA guidelines, respectively. Levels of awareness, treatment, and control of high blood pressure were low in women. Among children, significant predictors of high blood pressure were obesity, overweight, and indigenous ethnicity. Among women, significant predictors of high blood pressure included obesity, overweight, and diabetes. CONCLUSION: The prevalence of high blood pressure was high among Guatemalan women and children. Overweight and obesity were strong risk factors for high blood pressure. Increasing obesity prevention and control programs may help prevent high blood pressure, and expanding high blood pressure screening and treatment could increase awareness and control of high blood pressure in Guatemala. |
Rotavirus group A genotype circulation patterns across Kenya before and after nationwide vaccine introduction, 2010-2018.
Mwanga MJ , Owor BE , Ochieng JB , Ngama MH , Ogwel B , Onyango C , Juma J , Njeru R , Gicheru E , Otieno GP , Khagayi S , Agoti CN , Bigogo GM , Omore R , Addo OY , Mapaseka S , Tate JE , Parashar UD , Hunsperger E , Verani JR , Breiman RF , Nokes DJ . BMC Infect Dis 2020 20 (1) 504 BACKGROUND: Kenya introduced the monovalent G1P [8] Rotarix(R) vaccine into the infant immunization schedule in July 2014. We examined trends in rotavirus group A (RVA) genotype distribution pre- (January 2010-June 2014) and post- (July 2014-December 2018) RVA vaccine introduction. METHODS: Stool samples were collected from children aged < 13 years from four surveillance sites across Kenya: Kilifi County Hospital, Tabitha Clinic Nairobi, Lwak Mission Hospital, and Siaya County Referral Hospital (children aged < 5 years only). Samples were screened for RVA using enzyme linked immunosorbent assay (ELISA) and VP7 and VP4 genes sequenced to infer genotypes. RESULTS: We genotyped 614 samples in pre-vaccine and 261 in post-vaccine introduction periods. During the pre-vaccine introduction period, the most frequent RVA genotypes were G1P [8] (45.8%), G8P [4] (15.8%), G9P [8] (13.2%), G2P [4] (7.0%) and G3P [6] (3.1%). In the post-vaccine introduction period, the most frequent genotypes were G1P [8] (52.1%), G2P [4] (20.7%) and G3P [8] (16.1%). Predominant genotypes varied by year and site in both pre and post-vaccine periods. Temporal genotype patterns showed an increase in prevalence of vaccine heterotypic genotypes, such as the commonly DS-1-like G2P [4] (7.0 to 20.7%, P < .001) and G3P [8] (1.3 to 16.1%, P < .001) genotypes in the post-vaccine introduction period. Additionally, we observed a decline in prevalence of genotypes G8P [4] (15.8 to 0.4%, P < .001) and G9P [8] (13.2 to 5.4%, P < .001) in the post-vaccine introduction period. Phylogenetic analysis of genotype G1P [8], revealed circulation of strains of lineages G1-I, G1-II and P [8]-1, P [8]-III and P [8]-IV. Considerable genetic diversity was observed between the pre and post-vaccine strains, evidenced by distinct clusters. CONCLUSION: Genotype prevalence varied from before to after vaccine introduction. Such observations emphasize the need for long-term surveillance to monitor vaccine impact. These changes may represent natural secular variation or possible immuno-epidemiological changes arising from the introduction of the vaccine. Full genome sequencing could provide insights into post-vaccine evolutionary pressures and antigenic diversity. |
An integrated infant and young child feeding and small-quantity lipid-based nutrient supplementation program is associated with improved gross motor and communication scores of children 6-18 months in the Democratic Republic of Congo
Addo OY , Tripp K , Nanama S , Albert B , Sandalinas F , Nanema A , Jefferds ME , Clayton HB , Whitehead RDJr , Garg A , Kupka R , Locks LM . J Pediatr 2020 222 154-163 OBJECTIVE: To evaluate the impact of an infant, young child feeding practices-small-quantity lipid nutrient supplements (SQ-LNS) intervention on child development scores in children aged 6-18 months in the Katanga Province, Democratic Republic of Congo (DRC). STUDY DESIGN: We analyzed data of 2595 children from 2 health zones in a quasi-experimental design with preimplementation and postimplementation surveys to evaluate program impact on child development scores. Standard care was received in the comparison health zone and the intervention health zone received standard care plus enhanced infant, young child feeding practices with a monthly supply of 28 SQ-LNS sachets for up to 1 year. Program exposure and communication and motor domains of the Ages and Stages questionnaire were collected to assess changes in child development scores. A quasi-intent-to-treat and adjusted difference-in-difference analyses were used to quantify impact of the enhanced compared with the standard package. RESULTS: In adjusted models contrasting endline with baseline, there was a greater relative increase in proportion of children with normal communication (difference-in-difference, +13.7% [95%CI, 7.9-19.6; P < .001] and gross motor scores, +7.4% [95% CI: 1.3-13.5; P < .001]) in the intervention vs comparison health zones. Further, in separate analyses among children of intervention health zone at endline, each additional SQ-LNS distribution was associated with +0.09 (95% CI, 0.03-0.16) z-score unit increase in gross motor scores (P < .01). CONCLUSIONS: The integrated infant, young child feeding practice-SQ-LNS intervention was positively associated with larger relative improvements in measures of child communication and motor development in the Katanga province of DRC. |
Data needed to respond appropriately to anemia when it is a public health problem
Williams AM , Addo OY , Grosse SD , Kassebaum NJ , Rankin Z , Ballesteros KE , Olsen HE , Sharma AJ , Jefferds ME , Mei Z . Ann N Y Acad Sci 2019 1450 (1) 268-280 Although the proportion of anemia amenable to change varies by population, the World Health Organization (WHO) criteria used to describe the public health severity of anemia are based on population prevalences. We describe the importance of measuring iron and other etiologic indicators to better understand what proportion of anemia could be responsive to interventions. We discuss the necessity of measuring inflammation to interpret iron biomarkers and documenting anemia of inflammation. Finally, we suggest assessing nonmodifiable genetic blood disorders associated with anemia. Using aggregated results from the Global Burden of Disease 2016, we compare population prevalence of anemia with years lived with disability (YLD) estimates, and the relative contributions of mild, moderate, and severe anemia to YLD. Anemia prevalences correlated with YLD and the relative proportion of moderate or severe anemia increased with anemia prevalence. However, individual-level survey data revealed irregular patterns between anemia prevalence, the prevalence of moderate or severe anemia, and the prevalence of iron deficiency anemia (IDA). We conclude that although the WHO population prevalence criteria used to describe the public health severity of anemia are important for policymaking, etiologic-specific metrics that take into account IDA and other causes will be necessary for effective anemia control policies. |
Reexamination of hemoglobin adjustments to define anemia: altitude and smoking
Sharma AJ , Addo OY , Mei Z , Suchdev PS . Ann N Y Acad Sci 2019 1450 (1) 190-203 The correct interpretation of hemoglobin (Hb) to identify anemia requires adjusting for altitude and smoking. Current adjustments were derived using data collected before 1985, from low-income preschool-aged children (PSC) in the United States and indigenous men in Peru for altitude, and from White women of reproductive age (WRA) in the United States for smoking. Given the oldness and limited representativeness of these data, we reexamined associations between Hb and altitude and/or smoking using 13 population-based surveys and 1 cohort study each conducted after 2000. All WHO regions except South-East Asia were represented. The dataset included 68,193 observations among PSC (6-59 months) and nonpregnant WRA (15-49 years) with data on Hb and altitude (-28 to 4000 m), and 19,826 observations among WRA with data on Hb and smoking (status or daily cigarette quantity). Generalized linear models were used to assess the robustness of associations under varying conditions, including controlling for inflammation-corrected iron and vitamin A deficiency. Our study confirms that Hb should be adjusted for altitude and/or smoking; these adjustments are additive. However, recommendations for Hb adjustment likely need updating. Notably, current recommendations may underadjust Hb for light smokers and for those residing at lower altitudes and overadjust Hb for those residing at higher altitudes. |
Four years after implementation of a national micronutrient powder program in Kyrgyzstan, prevalence of iron deficiency and iron deficiency anemia is lower, but prevalence of vitamin A deficiency is higher
Lundeen EA , Lind JN , Clarke KEN , Aburto NJ , Imanalieva C , Mamyrbaeva T , Ismailova A , Timmer A , Whitehead RDJr , Praslova L , Samohleb G , Minbaev M , Addo OY , Serdula MK . Eur J Clin Nutr 2018 73 (3) 416-423 BACKGROUND/OBJECTIVES: In 2009, the Ministry of Health of Kyrgyzstan launched a national Infant and Young Child Nutrition (IYCN) program which included point-of-use fortification of foods with micronutrient powders (MNP) containing iron, vitamin A, and other micronutrients. Caretakers of children aged 6-23 months were given 30 sachets of MNP every 2 months. Micronutrient surveys were conducted in 2009 and 2013. The objective of the study was to compare the prevalence of anemia and deficiencies of iron and vitamin A among children aged 6-29 months prior to the MNP program (2009) with those after full implementation (2013). SUBJECTS/METHODS: Cross-sectional national surveys were conducted in 2009 (n = 666) and 2013 (n = 2150). Capillary blood samples were collected to measure hemoglobin, iron (ferritin and soluble transferrin receptor [sTfR]) and vitamin A (retinol binding protein [RBP]) status, and inflammation status (C-reactive protein [CRP] and alpha-1-acid glycoprotein [AGP]). Ferritin, sTfR, and RBP were adjusted for inflammation; hemoglobin was adjusted for altitude. RESULTS: The prevalence of anemia was non-significantly lower in 2013 compared to 2009 (32.7% vs. 39.0%, p = 0.076). Prevalence of inflammation-adjusted iron deficiency (54.8% vs. 74.2%, p<0.001) and iron deficiency anemia (IDA, 25.5% vs. 35.1%, p = 0.003) were lower and the prevalence of inflammation-adjusted vitamin A deficiency was higher (4.3% vs. 2.0%, p = 0.013) in 2013 compared to 2009. CONCLUSIONS: Four years after the initiation of a national Infant and Young Child Nutrition program including the introduction of point-of-use fortification with MNP, the prevalence of iron deficiency and IDA is lower, but the prevalence of vitamin A deficiency is higher. |
Approaches to assess vitamin A status in settings of inflammation: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) Project
Larson LM , Guo J , Williams AM , Young MF , Ismaily S , Addo OY , Thurnham D , Tanumihardjo SA , Suchdev PS , Northrop-Clewes CA . Nutrients 2018 10 (8) The accurate estimation of vitamin A deficiency (VAD) is critical to informing programmatic and policy decisions that could have important public health implications. However, serum retinol and retinol binding protein (RBP) concentrations, two biomarkers often used to estimate VAD, are temporarily altered during the acute phase response, potentially overestimating the prevalence of VAD in populations with high levels of inflammation. In 22 nationally-representative surveys, we examined (1) the association between C-reactive protein (CRP) or alpha1-acid glycoprotein (AGP) and retinol or RBP, and (2) how different adjustment approaches for correcting for inflammation compare with one another. In preschool age children (PSC) and school age children (SAC), the association between inflammation and retinol and RBP was largely statistically significant; using the regression approach, adjustments for inflammation decreased the estimated prevalence of VAD compared to unadjusted VAD (range: -22.1 to -6.0 percentage points). In non-pregnant women of reproductive age (WRA), the association between inflammation and vitamin A biomarkers was inconsistent, precluding adjustments for inflammation. The burden of VAD can be overestimated if inflammation is not accounted for, and the regression approach provides a method for adjusting retinol and RBP for inflammation across the full range of concentrations in PSC and SAC. |
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