Journal Article

Variant hemoglobin phenotypes may account for differential erythropoiesis-stimulating agent dosing in African-American hemodialysis patients

Derebail, Vimal K., Falk, Ronald J., Ansede, Heather, Key, Nigel S., Rosamond, Wayne D., Kshirsagar, Abhijit V., Nachman, Patrick H.

2011

Overview

African-American patients with end-stage renal disease have historically lower hemoglobin concentrations and higher requirements of erythropoiesis-stimulating agent (ESA). While disparities in health-care access may partially explain these findings, the role of variant hemoglobin, such as sickle trait, has not been investigated. To clarify this, we evaluated 154 African-American patients receiving in-center hemodialysis with available hemoglobin phenotyping. The primary exposure was any abnormal hemoglobin variant and the primary outcome of higher-dose ESA was defined as a dose of 6500 or more units per treatment. Logistic regression assessed the association between variant hemoglobin and higher-dose ESA. Covariates included age, gender, diabetes, iron parameters, intravenous iron dose, parathyroid hormone, albumin, phosphorus, body mass index, vascular access type, hospitalization/missed treatments, smoking status, alcohol abuse, and gastrointestinal bleeding. Of 33 patients with variant hemoglobin, 24 had HbAS and 9 had HbAC. Univariate odds of higher-dose ESA among those with hemoglobin variants were twice that of those with the normal HbAA phenotype (odds ratio 2.05). In multivariate models, the likelihood of higher-dose ESA had an odds ratio of 3.31 and the nature of this relationship did not change in Poisson regression or sensitivity analyses. Hence, our findings may explain, in part, the difference in ESA dosing between Caucasians and African-Americans with end-stage renal disease but await further study.

• Publisher: Elsevier Inc,Nature Publishing Group,Elsevier Limited
• Subject: Aged / anemia / Anemia, Sickle Cell - blood / Anemia, Sickle Cell - drug therapy / Anemia, Sickle Cell - ethnology / Anemia, Sickle Cell - genetics / Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy / Biological and medical sciences / Black or African American - genetics / Cross-Sectional Studies / Drug Dosage Calculations / Drug Resistance - genetics / Emergency and intensive care: renal failure. Dialysis management / erythropoietin / ESRD / Female / Genotype / Hematinics - adverse effects / Hemoglobin C - genetics / Hemoglobin C - metabolism / Hemoglobin C Disease - blood / Hemoglobin C Disease - drug therapy / Hemoglobin C Disease - ethnology / Hemoglobin C Disease - genetics / Hemoglobin, Sickle - genetics / Hemoglobin, Sickle - metabolism / Humans / Intensive care medicine / Kidney Failure, Chronic - blood / Kidney Failure, Chronic - ethnology / Kidney Failure, Chronic - therapy / Logistic Models / Male / Medical sciences / Middle Aged / Nephrology. Urinary tract diseases / Nephropathies. Renovascular diseases. Renal failure / Odds Ratio / Phenotype / Renal Dialysis / Renal failure / Risk Assessment / Risk Factors / United States - epidemiology