Sickle cell trait (HbAS) is twice as prevalent among African Americans with end-stage renal disease (ESRD) than in the general African-American population, data show.
The data emerged from a study that included 188 African-American patients receiving dialysis at four centers affiliated with the University of North Carolina (UNC) Kidney Center in Chapel Hill. All subjects underwent hemoglobin phenotyping for HbAS.
The study also determined HbAS prevalence in the local population by studying 6,729 African-American newborns screened for hemoglobinopathies in three North Carolina counties served by the dialysis centers.
The researchers, led by Vimal K. Derebail, MD, of the UNC Kidney Center, found that 15% of the dialysis cohort had HbAS compared with 7.1% of the screened newborns, according to report in the Journal of the American Society of Nephrology (2010; published online ahead of print).
In addition, hemoglobin C trait (HbAC) occurred in 5% of the dialysis patients versus 2% in the general African-American population. ). HbAC is a hemoglobin variant found in African Americans. If an individual with this variant has a child with somebody who has HbAS, a sickle cell disease (hemoglobin SC disease) can develop in the child.
“The high prevalence these hemoglobinopathies suggests that they may contribute to progression to ESRD by providing a background of renal injury,” the investigators wrote. “Our findings also raise questions as to how the presence of HbAS or HbAC may affect management of ESRD patients.”
Epidemiologic studies have linked HbAS with microalbuminuria and proteinuria, especially among men with diabetes, and shown that African Americans with autosomal dominant polycystic kidney disease and HbAS progress to end-stage renal disease more quickly than those without the trait, the authors noted.