The prevalence of kidney failure warranting dialysis or transplantation more than doubled between 2000 and 2019 to nearly 800,000 persons in the United States, with diabetes as the leading cause in 47% of those affected.1,2 The incidence of chronic kidney disease (CKD) among patients with diabetes is unknown, yet such data are vital for identifying high-risk populations, determining the effectiveness of interventions, and assessing the effects on health care delivery and public health responses.

This article describes trends in end-stage kidney disease in the US between 2000 and 2019, when a 42% increase in incident cases and a 119% increase in prevalent cases of end-stage kidney disease were observed. Hypertension and diabetes mellitus were the primary causes of both incident and prevalent cases of end-stage kidney disease. These trends suggest there will be an ongoing increase in the demand for organ transplantation, a potential negative impact on future organ supply, and underscore the need for increased access to kidney transplantation nationally.

BACKGROUND: Current studies examining the effects of high concentrations of red blood cell (RBC) or serum folates assume that high folate concentrations are an indicator of high folic acid intakes, often ignoring the contributions of other homeostatic and biological processes, such as kidney function. OBJECTIVE: The current study examined the relative contributions of declining kidney function, as measured by the risk of chronic kidney disease (CKD), and usual total folic acid intake on the concentrations of RBC folate and serum folate (total as well as individual folate forms). DESIGN: Cross-sectional data from the National Health and Nutrition Examination Survey (NHANES) collected in 2-year cycles were combined from 2011 to 2018. A total of 18,127 participants aged ≥16 years with available folate measures, kidney biomarker data (operationalized as a categorical CKD risk variable describing the risk of progression), and reliable dietary recall data were analyzed. RESULTS: RBC folate concentrations increased as CKD risk increased: low risk, 1089 (95% CI: 1069, 1110) nmol/L; moderate risk, 1189 (95% CI: 1158, 1220) nmol/L; high risk, 1488 (95% CI: 1419, 1561) nmol/L; and highest risk, 1443 (95% CI: 1302, 1598) nmol/L (p < 0.0001). Similarly, serum total folate concentrations increased as CKD risk increased: low risk: 37.1 (95% CI: 26.3, 38.0) nmol/L; moderate risk: 40.2 (95% CI: 38.8, 41.7) nmol/L; high risk: 48.0 (95% CI: 44.3, 52.1) nmol/L; the highest Risk: 42.8 (95% CI: 37.8, 48.4) nmol/L (p < 0.0001). The modeled usual intake of folic acid showed no difference among CKD risk groups, with a population median of 225 (interquartile range: 108-390) µg/day. CONCLUSION: Both RBC and serum folate concentrations increased with declining kidney function without increased folic acid intake. When analyzing associations between folate concentrations and disease outcomes, researchers may want to consider the confounding role of kidney function.

BACKGROUND: Patients with advanced kidney disease are less likely than many patients with other types of serious illness to enroll in hospice. Little is known about real-world clinical decision-making related to hospice for members of this population. METHODS: We used a text search tool to conduct a thematic analysis of documentation pertaining to hospice in the electronic medical record system of the Department of Veterans Affairs, for a national sample of 1000 patients with advanced kidney disease between 2004 and 2014 who were followed until October 8, 2019. RESULTS: Three dominant themes emerged from our qualitative analysis of the electronic medical records of 340 cohort members with notes containing hospice mentions: (1) hospice and usual care as antithetical care models: clinicians appeared to perceive a sharp demarcation between services that could be provided under hospice versus usual care and were often uncertain about hospice eligibility criteria. This could shape decision-making about hospice and dialysis and made it hard to individualize care; (2) hospice as a last resort: patients often were referred to hospice late in the course of illness and did not so much choose hospice as accept these services after all treatment options had been exhausted; and (3) care complexity: patients' complex care needs at the time of hospice referral could complicate transitions to hospice, stretch the limits of home hospice, and promote continued reliance on the acute care system. CONCLUSIONS: Our findings underscore the need to improve transitions to hospice for patients with advanced kidney disease as they approach the end of life.

OBJECTIVE: Diabetes-related end-stage kidney disease (ESKD-D) disproportionately affects U.S. racial/ethnic minority populations compared with whites. However, from 1996 to 2013, ESKD-D incidence among American Indians and Alaska Natives (AIANs) and blacks declined. We assessed recent ESKD-D incidence data to determine whether trends by race/ethnicity have changed since 2013. RESEARCH DESIGN AND METHODS: U.S. Renal Data System data from 2000 to 2016 were used to determine the number of whites, blacks, AIANs, Asians, and Hispanics aged >/=18 years with newly treated ESKD-D (with diabetes listed as primary cause). Using census population estimates as denominators, annual ESKD-D incidence rates were calculated and age adjusted to the 2000 U.S. standard population. Joinpoint regression was used to analyze trends and estimate an average annual percent change (AAPC) in incidence rates. RESULTS: For adults overall, from 2000 to 2016, age-adjusted ESKD-D incidence rates decreased by 53% for AIANs (66.7-31.2 per 100,000, AAPC -4.5%, P < 0.001), by 33% for Hispanics (50.0-33.3, -2.1%, P < 0.001), and by 20% for blacks (56.2-44.7, -1.6%, P < 0.001). However, during the study period, age-adjusted ESKD-D incidence rates did not change significantly for Asians and increased by 10% for whites (15.4-17.0, 0.6%, P = 0.01). In 2016, ESKD-D incidence rates in AIANs, Hispanics, and blacks were approximately 2.0-2.5 times higher than whites. CONCLUSIONS: ESKD-D incidence declined for AIANs, Hispanics, and blacks and increased for whites. Continued efforts might be considered to reverse the trend in whites and sustain and lower ESKD-D incidence in the other populations.

BACKGROUND: Acid retention associated with reduced GFR exacerbates nephropathy progression in partial nephrectomy models of CKD and might be reflected in CKD patients with reduced eGFR by increased anion gap (AG). METHODS: We explored the presence of AG and its association with CKD in 14,924 adults, aged >/=20 years and eGFR>/=15ml/min/1.73m(2), enrolled in the National Health and Nutrition Examination Survey III, 1988-1994 using multivariable regression analysis. The model was adjusted for socio-demographic characteristics, diabetes, and hypertension. We further examined the association between AG and incident end-stage renal disease using frailty models, adjusting for demographics, clinical factors, BMI, serum albumin, bicarbonate, eGFR, and urinary albumin-to-creatinine ratio, by following 558 adults with moderate CKD for 12 years via the United States Renal Data System. Laboratory measures determined AG using the traditional, albumin-corrected, and full AG definitions. RESULTS: Individuals with moderate CKD (eGFR 30-59 ml/min/1.73 m(2)) had a greater AG than those with eGFR>/=60 ml/min in multivariable regression analysis with adjustment for covariates. We found a graded relationship between the adjusted mean for all three definitions of AG and eGFR categories (p trend<0.0001). During follow-up, 9.2% of adults with moderate CKD developed ESRD. Those with AG in the highest tertile had a higher risk of ESRD, after adjusting for covariates in a frailty model (Relative risk [95% CI] for traditional AG:1.8[1.2-2.3]), compared to those in the middle tertile. CONCLUSIONS: The data suggest that high AG, even after adjusting for serum bicarbonate, is a contributing acid-base mechanism to CKD progression in moderate CKD.

Lower eGFR 1 year after kidney transplant is associated with shorter allograft and patient survival. We examined how practice changes in the past decade correlated with time trends in average eGFR at 1 year after kidney transplant in the United States in a cohort of 189,944 patients who received a kidney transplant between 2001 and 2013. We calculated the average eGFR at 1 year after transplant for the recipient cohort of each year using the appropriate Modification of Diet in Renal Disease equation depending on the prevailing methodology of creatinine measurement, and used linear regression to model the effects of practice changes on the national post-transplant eGFR trend. Between the 2001-2005 period and the 2011-2013 period, average 1-year post-transplant eGFR remained essentially unchanged, with differences of 1.34 (95% confidence interval, 1.03 to 1.65) ml/min per 1.73 m2 and 0.66 (95% confidence interval, 0.32 to 1.01) ml/min per 1.73 m2 among deceased and living donor kidney transplant recipients, respectively. Over time, the mean age of recipients increased and more marginal organs were used; adjusting for these trends unmasked a larger temporal improvement in post-transplant eGFR. However, changes in immunosuppression practice had a positive effect on average post-transplant eGFR and balanced out the negative effect of recipient/donor characteristics. In conclusion, average 1-year post-transplant eGFR remained stable, despite increasingly unfavorable attributes in recipients and donors. With an aging ESRD population and continued organ shortage, preservation of average post-transplant eGFR will require sustained improvement in immunosuppression and other aspects of post-transplant care.

BACKGROUND: Poor access to food among low-income adults has been recognized as a risk factor for chronic kidney disease (CKD), but there are no data for the impact of food insecurity on progression to end-stage renal disease (ESRD). We hypothesized that food insecurity would be independently associated with risk for ESRD among persons with and without earlier stages of CKD. STUDY DESIGN: Longitudinal cohort study. SETTING & PARTICIPANTS: 2,320 adults (aged ≥ 20 years) with CKD and 10,448 adults with no CKD enrolled in NHANES III (1988-1994) with household income ≤ 400% of the federal poverty level linked to the Medicare ESRD Registry for a median follow-up of 12 years. PREDICTOR: Food insecurity, defined as an affirmative response to the food-insecurity screening question. OUTCOME: Development of ESRD. MEASUREMENTS: Demographics, income, diabetes, hypertension, estimated glomerular filtration rate, and albuminuria. Dietary acid load was estimated from 24-hour dietary recall. We used a Fine-Gray competing-risk model to estimate the relative hazard (RH) for ESRD associated with food insecurity after adjusting for covariates. RESULTS: 4.5% of adults with CKD were food insecure. Food-insecure individuals were more likely to be younger and have diabetes (29.9%), hypertension (73.9%), or albuminuria (90.4%) as compared with their counterparts (P<0.05). Median dietary acid load in the food-secure versus food-insecure group was 51.2 mEq/d versus 55.6 mEq/d, respectively (P=0.05). Food-insecure adults were more likely to develop ESRD (RH, 1.38; 95% CI, 1.08-3.10) compared with food-secure adults after adjustment for demographics, income, diabetes, hypertension, estimated glomerular filtration rate, and albuminuria. In the non-CKD group, 5.7% were food insecure. We did not find a significant association between food insecurity and ESRD (RH, 0.77; 95% CI, 0.40-1.49). LIMITATIONS: Use of single 24-hour diet recall; lack of laboratory follow-up data and measure of changes in food insecurity over time; follow-up of cohort ended 10 years ago. CONCLUSIONS: Among adults with CKD, food insecurity was independently associated with a higher likelihood of developing ESRD. Innovative approaches to address food insecurity should be tested for their impact on CKD outcomes.

In our AJKD article, we reported estimates of the future prevalence of CKD using existing definitions of the disease.1 In their letter, Drs Delanaye, El Nahas, and Glassock state that the high prevalence of CKD in persons aged 65 and older is primarily due to aging and does not represent an added mortality risk.2 A few studies have indeed found that estimated GFR values between 45 and 59 mL/min/1.73 m2 are not associated with increased mortality.3 However, other large epidemiologic studies have found that the relative and absolute risks of mortality are higher for the elderly with estimated GFR in this range than for the elderly with greater estimated GFR levels, even after controlling for albuminuria.4,5 Thus, we believe that CKD staging does provide prognostic information for persons aged 65 and older. We agree with Delanaye et al that not all persons who reach CKD stage 3a will progress to more advanced CKD stages; however, we disagree with their statement that “clearly stage 3a neither progresses to more severe stages nor shortens life expectancy” in persons aged 65 and older.

Small clinical trials have shown that a reduction in dietary acid load (DAL) improves kidney injury and slows kidney function decline; however, the relationship between DAL and risk of ESRD in a population-based cohort with CKD remains unexamined. We examined the association between DAL, quantified by net acid excretion (NAEes), and progression to ESRD in a nationally representative sample of adults in the United States. Among 1486 adults with CKD age≥20 years enrolled in the National Health and Nutrition Examination Survey III, DAL was determined by 24-h dietary recall questionnaire. The development of ESRD was ascertained over a median 14.2 years of follow-up through linkage with the Medicare ESRD Registry. We used the Fine-Gray competing risks method to estimate the association of high, medium, and low DAL with ESRD after adjusting for demographics, nutritional factors, clinical factors, and kidney function/damage markers and accounting for intervening mortality events. In total, 311 (20.9%) participants developed ESRD. Higher levels of DAL were associated with increased risk of ESRD; relative hazards (95% confidence interval) were 3.04 (1.58 to 5.86) for the highest tertile and 1.81 (0.89 to 3.68) for the middle tertile compared with the lowest tertile in the fully adjusted model. The risk of ESRD associated with DAL tertiles increased as eGFR decreased (P trend=0.001). Among participants with albuminuria, high DAL was strongly associated with ESRD risk (P trend=0.03). In conclusion, high DAL in persons with CKD is independently associated with increased risk of ESRD in a nationally representative population.

BACKGROUND: Awareness of chronic kidney disease (CKD), defined by kidney damage or reduced glomerular filtration rate, remains low in the United States, and few estimates of its future burden exist. STUDY DESIGN: We used the CKD Health Policy Model to simulate the residual lifetime incidence of CKD and project the prevalence of CKD in 2020 and 2030. The simulation sample was based on nationally representative data from the 1999 to 2010 National Health and Nutrition Examination Surveys. SETTING & POPULATION: Current US population. MODEL, PERSPECTIVE, & TIMELINE: Simulation model following up individuals from current age through death or age 90 years. OUTCOMES: Residual lifetime incidence represents the projected percentage of persons who will develop new CKD during their lifetimes. Future prevalence is projected for 2020 and 2030. MEASUREMENTS: Development and progression of CKD are based on annual decrements in estimated glomerular filtration rates that depend on age and risk factors. RESULTS: For US adults aged 30 to 49, 50 to 64, and 65 years or older with no CKD at baseline, the residual lifetime incidences of CKD are 54%, 52%, and 42%, respectively. The prevalence of CKD in adults 30 years or older is projected to increase from 13.2% currently to 14.4% in 2020 and 16.7% in 2030. LIMITATIONS: Due to limited data, our simulation model estimates are based on assumptions about annual decrements in estimated glomerular filtration rates. CONCLUSIONS: For an individual, lifetime risk of CKD is high, with more than half the US adults aged 30 to 64 years likely to develop CKD. Knowing the lifetime incidence of CKD may raise individuals' awareness and encourage them to take steps to prevent CKD. From a national burden perspective, we estimate that the population prevalence of CKD will increase in coming decades, suggesting that development of interventions to slow CKD onset and progression should be considered.

BACKGROUND: Diet can markedly affect acid-base status and it significantly influences chronic kidney disease (CKD) and its progression. The relationship of dietary acid load (DAL) and CKD has not been assessed on a population level. We examined the association of estimated net acid excretion (NAE(es)) with CKD; and socio-demographic and clinical correlates of NAE(es). METHODS: Among 12,293 U.S. adult participants aged >20 years in the National Health and Nutrition Examination Survey 1999-2004, we assessed dietary acid by estimating NAE(es) from nutrient intake and body surface area; kidney damage by albuminuria; and kidney dysfunction by eGFR < 60 ml/min/1.73 m(2) using the MDRD equation. We tested the association of NAE(es) with participant characteristics using median regression; while for albuminuria, eGFR, and stages of CKD we used logistic regression. RESULTS: Median regression results (beta per quintile) indicated that adults aged 40-60 years (beta [95% CI] = 3.1 [0.3-5.8]), poverty (beta [95% CI] = 7.1 [4.01-10.22]), black race (beta [95% CI] = 13.8 [10.8-16.8]), and male sex (beta [95% CI] = 3.0 [0.7- 5.2]) were significantly associated with an increasing level of NAE(es). Higher levels of NAE(es) compared with lower levels were associated with greater odds of albuminuria (OR [95% CI] = 1.57 [1.20-2.05]). We observed a trend toward greater NAE(es) being associated with higher risk of low eGFR, which persisted after adjustment for confounders. CONCLUSION: Higher NAE(es) is associated with albuminuria and low eGFR, and socio-demographic risk factors for CKD are associated with higher levels of NAE(es). DAL may be an important target for future interventions in populations at high risk for CKD.

Chronic kidney disease is now recognized to be a worldwide problem associated with significant morbidity and mortality and there is a steep increase in the number of patients reaching end-stage renal disease. In many parts of the world, the disease affects younger people without diabetes or hypertension. The costs to family and society can be enormous. Early recognition of CKD may help prevent disease progression and the subsequent decline in health and longevity. Surveillance programs for early CKD detection are beginning to be implemented in a few countries. In this article, we will focus on the challenges and successes of these programs with the hope that their eventual and widespread use will reduce the complications, deaths, disabilities, and economic burdens associated with CKD worldwide.

BACKGROUND: Albuminuria is associated with an increased risk of death independent of level of renal function. Whether this association is similar for adults of all ages is not known. METHODS: We examined the association between the albumin to creatinine ratio (ACR) and all-cause mortality after stratification by estimated glomerular filtration rate (eGFR) and age group in 94 934 veterans with diabetes mellitus. Cohort members had at least 1 ACR recorded in the Veterans Affairs Health Care System between October 1, 2002, and September 30, 2003, and were followed up for death through October 15, 2009. RESULTS: From the youngest to the oldest age group, the prevalence of an eGFR less than 60 mL/min/1.73 m(2) ranged from 11% to 41%; microalbuminuria (ACR 30-299 mg/g) ranged from 19% to 28%; and macroalbuminuria (ACR > or =300 mg/g) ranged from 3.2% to 3.7%. Of patients with an eGFR less than 60 mL/min/1.73 m(2), 72% of those younger than 65 years, 74% of those 65 to 74 years old, and 59% of those 75 years and older had an eGFR of 45 to 59 mL/min/1.73 m(2). In all age groups, less than 35% of these patients had albuminuria (ie, ACR > or =30 mg/g). In patients 75 years and older, the ACR was independently associated with an increased risk of death at all levels of eGFR after adjusting for potential confounders. In younger age groups, this association was present at higher levels of eGFRs but seemed to be attenuated at lower levels. CONCLUSION: The ACR is independently associated with mortality at all levels of eGFR in older adults with diabetes and may be particularly helpful for risk stratification in the large group with moderate reductions in eGFR.

OBJECTIVE: In this study, we build on the previous findings of increased diabetes prevalence among American Indian/Alaska Native (AI/AN) young adults, by studying the rate at which annual prevalence estimates of diagnosed diabetes increased from 1994 to 2007. DESIGN AND SETTING: For this study, BRFSS data for 1994-2007 from the 50 states, District of Columbia, Puerto Rico, Guam, and the Virgin Islands were analyzed. PARTICIPANTS: Only non-institutionalized adults aged 18 years and older were eligible to participate in the Behavioral Risk Factor Surveillance System survey. MAIN OUTCOME MEASURES: To examine the existence and strength of a trend, we analyzed plots and Spearman's rank correlation coefficients of annual prevalence estimates for each group of young adults. Mantel-Haenszel tests were employed to study the relationship of diagnosed diabetes prevalence and race (AI/ AN, non-Hispanic White), while controlling for the time periods 1994-2000 and 2001-2007. To quantify increases in the disparity of diagnosed diabetes prevalence and race (AI/ AN, non-Hispanic White), odds risk ratio estimates were employed to approximate corresponding prevalence ratio estimates for the time periods 1994-2000 and 2001-2007. RESULTS: Employing Spearman's test for trend resulted in observing, during 1994-2007, statistically significant increasing trends in the annual prevalence estimates of diagnosed diabetes among AI/AN and non-Hispanic White young adults. AI/AN young adults, on average, were 1.7 (95% CI; [1.12, 2.63]) times more likely than non-Hispanic White young adults to be diagnosed with diabetes during 1994-2000 and 2.5 (95% CI; [1.93, 3.32]) times more likely during 2001-2007. CONCLUSION: The findings in this study suggests that the disparity in the estimated prevalence of diagnosed diabetes between AI/AN and NHW young adults widened steadily from 2001 to 2007.