title: APOL1 Genotype and Race Differences in Incident Albuminuria and Renal Function Decline.
abstract: Variants in the APOL1 gene are associated with kidney disease in blacks. We examined associations of APOL1 with incident albuminuria and kidney function decline among 3030 young adults with preserved GFR in the Coronary Artery Risk Development in Young Adults (CARDIA) study. eGFR by cystatin C (eGFRcys) and albumin-to-creatinine ratio were measured at scheduled examinations. Participants were white (n=1700), high-risk black (two APOL1 risk alleles, n=176), and low-risk black (zero/one risk allele, n=1154). Mean age was 35 years, mean eGFRcys was 107 ml/min per 1.73 m(2), and 13.2% of blacks had two APOL1 alleles. The incidence rate per 1000 person-years (95% confidence interval) for albuminuria over 15 years was 15.6 (10.6-22.1) for high-risk blacks, 7.8 (6.4-9.4) for low-risk blacks, and 3.9 (3.1-4.8) for whites. Compared with whites, the odds ratio (95% confidence interval) for incident albuminuria was 5.71 (3.64-8.94) for high-risk blacks and 2.32 (1.73-3.13) for low-risk blacks. Adjustment for risk factors attenuated the difference between low-risk blacks and whites (odds ratio 1.21, 95% confidence interval 0.86-1.71). After adjustment, high-risk blacks had a 0.45% faster yearly eGFRcys decline over 9.3 years compared with whites. Low-risk blacks also had a faster yearly eGFRcys decline compared with whites, but this difference was attenuated after adjustment for risk factors and socioeconomic position. In conclusion, blacks with two APOL1 risk alleles had the highest risk for albuminuria and eGFRcys decline in young adulthood, whereas disparities between low-risk blacks and whites were related to differences in traditional risk factors.
authors.affiliation: Department of Medicine, University of California, San Francisco, California; San Francisco VA Medical Center, San Francisco, California; carmenalicia.peralta@ucsf.edu.
authors.forename: Carmen A
authors.initials: CA
authors.lastname: Peralta
authors.affiliation: Department of Medicine, University of California, San Francisco, California;
authors.forename: Kirsten
authors.initials: K
authors.lastname: Bibbins-Domingo
authors.affiliation: Department of Biostatistics, University of California, San Francisco, California;
authors.forename: Eric
authors.initials: E
authors.lastname: Vittinghoff
authors.affiliation: Department of Biostatistics, University of California, San Francisco, California;
authors.forename: Feng
authors.initials: F
authors.lastname: Lin
authors.affiliation: The University of Texas Health Science Center at Houston, Houston, Texas;
authors.forename: Myriam
authors.initials: M
authors.lastname: Fornage
authors.affiliation: Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland; and.
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Kopp
authors.affiliation: Basic Research Laboratory, Center for Cancer Research, National Cancer Institute, Leidos Biomedical Inc., Frederick National Laboratory, Frederick, Maryland.
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Winkler
mesh_terms: D000328:Adult; D001741:Black or African American / Q000235:genetics* / Q000706:statistics & numerical data; D000419:Albuminuria / Q000208:ethnology* / Q000235:genetics; D000483:Alleles; D000075944:Apolipoprotein L1; D001053:Apolipoproteins / Q000235:genetics*; D055316:Cystatin C / Q000097:blood; D005260:Female; D005838:Genotype; D005919:Glomerular Filtration Rate; D006801:Humans; D015994:Incidence; D008075:Lipoproteins, HDL / Q000235:genetics*; D008297:Male; D051437:Renal Insufficiency / Q000208:ethnology* / Q000503:physiopathology; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D044465:White People / Q000235:genetics* / Q000706:statistics & numerical data
chemical_list: C108666:APOL1 protein, human; D000075944:Apolipoprotein L1; D001053:Apolipoproteins; D055316:Cystatin C; D008075:Lipoproteins, HDL
keywords: APOL1; albumin to creatinine ratio; apol1; incident albuminuria; kidney function decline; socioeconomic position (SEP)