Race,Apol1risk Variants, And Clinical Outcomes Among Older Adults: Thearicstudy

BACKGROUND/OBJECTIVES APOL1high-risk genotypes confer an increased risk for kidney disease, but their clinical significance among older adults remains unclear. We aimed to determine whetherAPOL1genotype status (high risk = 2 risk alleles; low risk = 0-1 risk alleles) and self-reported race (Black; White) are associated with number of hospitalizations, incident chronic kidney disease (CKD), end-stage renal disease (ESRD), and mortality among older adults participating in a community-based cohort study. DESIGN Observational longitudinal cohort study. SETTING The Atherosclerosis Risk in Communities (ARIC) study. PARTICIPANTS Community-dwelling older adults (mean age = 75.8 years; range = 66-90 years). RESULTS Among 5,564 ARIC participants (78.2% White, 19.1%APOL1low-risk Black, and 2.7%APOL1high-risk Black), the proportion with creatinine and cystatin C-based estimated glomerular filtration rate (eGFR(CrCys)) below 60 mL/min/1.73 m(2)at baseline was 40.6%, 34.8%, and 43.2%, respectively. Over a mean follow-up of 5.1 years,APOL1high-risk Blacks had a 2.67-fold higher risk for ESRD compared with low-risk Blacks (95% confidence interval [CI] = 1.05-6.79) in models adjusted for age and sex. This association was no longer significant upon further adjustment for baseline eGFR(CrCys)and albuminuria (hazard ratio [HR] = 1.08; 95% CI = .39-2.96). Rate of hospitalizations and risks of mortality and incident CKD did not differ significantly byAPOL1genotype status. Compared with Whites, Blacks had 1.85-fold and 3.45-fold higher risks for incident CKD and ESRD, respectively, in models adjusted for age, sex, eGFR(CrCys), and albuminuria. These associations persisted after additional adjustments for clinical/socioeconomic factors andAPOL1genotype (incident CKD: HR = 1.38; 95% CI = 1.06-1.81; ESRD: HR = 3.20; 95% CI = 1.16-8.86). CONCLUSION Among older Black adults,APOL1high-risk genotypes were associated with lower kidney function and therefore higher risk of ESRD. Racial disparities in incident kidney disease persisted in older age and were not fully explained byAPOL1.