Apolipoprotein L1 gene variants associate with prevalent kidney but not prevalent cardiovascular disease in the Systolic Blood Pressure Intervention Trial

Abstract

Apolipoprotein L1 gene (APOL1) G1 and G2 coding variants are strongly associated with chronic kidney disease (CKD) in African Americans. Here APOL1 association was tested with baseline estimated glomerular filtration rate (eGFR), urine albumin:creatinine ratio (UACR), and prevalent cardiovascular disease (CVD) in 2,571 African Americans from the Systolic Blood Pressure Intervention Trial (SPRINT), a trial assessing effects of systolic blood pressure reduction on renal and CVD outcomes. Logistic regression models that adjusted for potentially important confounders tested for association between APOL1 risk variants and baseline clinical CVD (myocardial infarction, coronary or carotid artery revascularization) and CKD (eGFR under 60 ml/min/1.73m2 and/or UACR over 30 mg/g). African American SPRINT participants were 45.3% female with mean (median) age of 64.3 (63) years, mean arterial pressure 100.7 (100) mmHg, eGFR 76.3 (77.1) ml/min/1.73m2, UACR 49.9 (9.2) mg/g, and 8.2% had clinical CVD. APOL1 (recessive inheritance) was positively associated with CKD (odds ratio 1.37, 95% confidence interval 1.08–1.73) and log UACR estimated slope [β] 0.33) and negatively associated with eGFR (β −3.58), all significant. APOL1 risk variants were not significantly associated with prevalent CVD (1.02, 0.82–1.27). Thus, SPRINT data show that APOL1 risk variants are associated with mild CKD but not prevalent CVD in African American with a UACR under 1000 mg/g.