Sickle cell trait (SCT) is strongly associated with an increased risk for end-stage renal disease (ESRD) among black individuals, according to a new study. The degree of risk for ESRD was similar to that conferred by APOL1 high-risk genotypes, researchers concluded.
Rakhi P. Naik, MD, of Johns Hopkins University School of Medicine in Baltimore, and colleagues evaluated 9909 self-reported blacks who were in the population-based REGARDS [Reasons for Geographic and Racial Differences in Stroke] study. The group included 739 individuals with SCT, 243 with hemoglobin C trait, and 8927 non-carriers. ESRD developed in 40 SCT carriers (5.4%), and 6 carriers of hemoglobin C trait, and 234 non-carriers (2.6%), the researchers reported online ahead of print in the Journal of the American Society of Nephrology. The incidence rate for ESRD was 8.5 per 1000 person-years for SCT carriers versus 4.0 per 1000 person-years for non-carriers. Participants with SCT had a 2-fold higher risk for ESRD compared with those who did not have SCT. Hemoglobin C trait was not associated with prevalence chronic kidney disease or ESRD.
The incidence rate for ESRD among individuals with APOL1 high-risk genotypes was 6.6 per 1000 person-years. These individuals had a nearly 1.8 times higher risk for ESRD than those without APOL1 high-risk genotypes. The investigators noted that APOL1 high-risk genotypes, which are present in about 11%–13% of blacks, are the most widely recognized genetic contributors to ESRD risk among blacks.
“Unlike APOL1, testing for SCT is widely performed in newborn screening programs, in athletics, and in pregnancy counseling, therefore, these findings may have immediate implications for policy and treatment recommendations in SCT,” Dr Naik and colleagues concluded.
1. Naik RP, Irvin MR, Judd S, et al. Sickle cell trait and the risk of ESRD in blacks. J Am Soc Nephrol 2017; published online ahead of print. doi: 10.1681/ASN.2016101086