Supplementary Material for: Apolipoprotein L1 Genetic Variants Are Associated with Chronic Kidney Disease but Not with Cardiovascular Disease in a Population Referred for Cardiac Catheterization

<p><b><i>Background:</i></b> While the association between <i>APOL1</i> genetic variants and chronic kidney disease (CKD) has been established, their association with cardiovascular disease (CVD) is unclear. This study sought to understand CKD and cardiovascular risk conferred by <i>APOL1</i> variants in a secondary cardiovascular prevention population. <b><i>Methods:</i></b> Two risk variants in <i>APOL1</i> were genotyped in African-Americans (<i>n</i> = 1,641) enrolled in the CATHGEN biorepository, comprised of patients referred for cardiac catheterization at Duke University Hospital, Durham, NC, USA (2001-2010). Individuals were categorized as noncarriers (<i>n</i> = 722), heterozygote (<i>n</i> = 771), or homozygote carriers (<i>n</i> = 231) of <i>APOL1 </i>risk alleles. Multivariable logistic regression and Cox proportional hazards models adjusted for CVD risk factors were used to assess the association between <i>APOL1</i> risk variants and prevalent and incident CKD, prevalent coronary artery disease (CAD), incident CVD events, and mortality. <b><i>Results:</i></b> The previously identified association between <i>APOL1 </i>variants and prevalent CKD was confirmed (OR: 1.85, 95% CI: 1.33-2.57, <i>p</i> = 0.0002). No statistically significant associations were detected between <i>APOL1</i> variants and incident CKD or prevalent CAD, incident CVD events or mortality. Age, type 2 diabetes, and ejection fraction at baseline were significant clinical factors that predicted the risk of incident CKD in a subgroup analysis of <i>APOL1</i> homozygous individuals. <b><i>Conclusion:</i></b><i>APOL1</i> genetic variants are not associated with CAD or incident CVD events in a cohort of individuals with a high burden of cardiometabolic risk factors. In individuals with homozygous <i>APOL1</i> status, factors that predicted subsequent CKD included age, presence of type 2 diabetes, and ejection fraction at baseline.</p>