Background Strong racial discrepancies in end-stage renal disease exist. to compare racial variations in rapid decrease (eGFRcys decrease >3% per year) by study period (10-15 years after baseline examination defining period 1 and >15-20 years after baseline examination defining period 2). Results Mean age was 35 ± 3.6 (SD) years mean eGFRcys was 110 ± 20 ml/min/1.73m2 for Blacks and 104 ± 17 ml/min/1.73m2 for Whites at baseline. For both Blacks and Whites eGFRcys decrease was minimal at more youthful age groups (<35 years) and eGFRcys loss accelerated at older ages. However acceleration of eGFRcys decrease occurred at earlier age groups for Blacks than Whites. Blacks experienced somewhat faster annualized rates of decrease compared with whites but variations D-(-)-Quinic acid were attenuated after adjustment in period 1 (0.13 ml/min/1.73m2 per year faster; p=0.2). In contrast during period 2 Blacks experienced significantly faster annualized rates of decrease even after adjustment (0.32 ml/min/1.73m2 per year faster; p=0.003). Prevalence of quick decrease was significantly higher among Blacks vs. Whites with prevalence rate ratios of 1 1.31 (95% CI 1.04 for period 1 and 1.24 (95% CI 1.09 for period 2. Variations were attenuated after full adjustment: modified prevalence rate ratios were 1.20 (95% CI 0.95 for period 1 and 1.10 (95% CI 0.96 for period 2. Limitations No measured GFR. Conclusions eGFRcys decrease differs by race at early age groups with faster annualized rates of decrease among blacks. SVIL Long term studies are required to explain observed variations. End stage renal disease (ESRD) affects Black People in america disproportionately and reasons for the high rates of ESRD in Blacks remain unclear. Prior literature suggested D-(-)-Quinic acid that Blacks may encounter faster D-(-)-Quinic acid progression from founded chronic kidney disease (CKD) defined as an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73m2 to ESRD compared with Whites.(1 2 Recent findings from your Coronary Artery Risk Development in Young Adults (CARDIA) Study showed that Blacks may D-(-)-Quinic acid have a higher risk of developing CKD.(3) Moreover in a large sample of middle-aged adults with eGFR >60 ml/min/1.73m2 Blacks had faster rates of kidney function decrease compared with Whites and these differences were not fully explained by traditional risk factors.(4) While these findings suggest that race differences in kidney function decrease may happen earlier in the disease course than previously thought population trajectories of kidney function loss D-(-)-Quinic acid in young healthy adults with preserved eGFR are not well established.(5) Moreover racial differences in these trajectories have not been fully examined. In part studies have been limited by the fact that repeated 24-hour urine collections over long periods are not feasible in large contemporary epidemiological studies. In addition serum creatinine the current clinical standard is usually a function of muscle mass which differs by race/ethnicity and may result in estimates of GFR biased by race. (6) Cystatin C is an alternative filtration marker that is not influenced by muscle mass age or race and in some studies it has shown to be a more sensitive marker for GFR decline when the GFR is usually preserved.(7 8 Cystatin C also has stronger and more linear associations with adverse outcomes and improves CKD classification and risk stratification compared with creatinine.(9-11) Therefore we have designed this study to (1) evaluate trajectories of kidney function loss in a population of young healthy Blacks and Whites with preserved kidney function; (2) investigate whether traditional kidney disease risk factors explain possible racial differences in early kidney function decline; and (3) identify racial differences and risk factors for rapid kidney function decline defined as an eGFR loss of >3% ml/min/1.73m2 per year. Understanding whether racial differences in the trajectories of kidney function loss are detectable early is usually paramount in developing adequate prevention strategies to reduce the overall burden and racial disparities of CKD. METHODS Participants We included participants from the CARDIA Study. CARDIA is usually a prospective cohort study sponsored by the National Heart Lung and Blood Institute designed to study early determinants of cardiovascular disease. Detailed methods for CARDIA have been published previously.(12) Briefly D-(-)-Quinic acid CARDIA recruited 5 115 Black and White persons aged 18-30 years between 1985 and.