Abstract
BACKGROUND: Two coding variants in the apo L1 gene (APOL1) are strongly associated with kidney disease in blacks. Kidney disease itself increases the risk of cardiovascular disease, but whether these variants have an independent direct effect on the risk of cardiovascular disease is unclear. Previous studies have had inconsistent results. METHODS: We conducted a two-stage individual participant data meta-analysis to assess the association of APOL1 kidney-risk variants with adjudicated cardiovascular disease events and death, independent of kidney measures. The analysis included 21,305 blacks from eight large cohorts. RESULTS: Over 8.9±5.0 years of follow-up, 2076 incident cardiovascular disease events occurred in the 16,216 participants who did not have cardiovascular disease at study enrollment. In fully-adjusted analyses, individuals possessing two APOL1 kidney-risk variants had similar risk of incident cardiovascular disease (coronary heart disease, myocardial infarction, stroke and heart failure; hazard ratio 1.11, 95% confidence interval, 0.96 to 1.28) compared to individuals with zero or one kidney-risk variant. The risk of coronary heart disease, myocardial infarction, stroke and heart failure considered individually was also comparable by APOL1 genotype. APOL1 genotype was also not associated with death. There was no difference in adjusted associations by level of kidney function, age, diabetes status, or body-mass index. CONCLUSIONS: In this large, two-stage individual participant data meta-analysis, APOL1 kidney-risk variants were not associated with incident cardiovascular disease or death independent of kidney measures.