Serum Creatinine Higher in Blacks Than Others on Dialysis
Difference in muscle mass doesn't seem to explain findings; higher creatinine linked to better survival
FRIDAY, April 18 (HealthDay News) -- Among patients with chronic kidney disease using hemodialysis, black individuals had significantly higher serum creatinine concentrations, which are associated with a lower risk of death in dialysis patients, according to research published online April 16 in the Clinical Journal of the American Society of Nephrology.
Joy Hsu, M.D., of the University of California San Francisco, and colleagues analyzed data from 3,009 adults who had been on thrice-weekly hemodialysis for at least three months. The researchers compared serum creatinine in black and non-black patients, adjusting for factors including diabetes, time on dialysis, body size, measurements of nutritional status, and body composition measured by bioelectrical impedance.
Adjusted mean serum creatinine concentrations in black patients were 11.7 milligrams per deciliter compared to 10 mg/dL in non-black patients, the investigators found. Higher concentrations were associated with a slightly lower risk of death (relative risk 0.93), with non-black patients showing this effect to a somewhat higher degree.
"In this study, we tested the hypothesis that differences in body composition -- and, by extension, creatinine generation -- would account entirely for racial differences in serum creatinine concentrations. Our results suggest that mechanisms other than increased creatinine production on the basis of larger muscle mass contribute to the higher serum creatinine in black individuals. Moreover, although it is indisputable that higher serum creatinine concentrations are associated with survival in dialysis patients, the reasons behind this association are unclear," the authors write.