Exploration of anaemia as a progression factor in African Americans with cardiovascular disease

Abstract

Despite the higher incidence of end-stage renal disease (ESRD) among African Americans, whites in the USA have a higher prevalence of chronic kidney disease. This may be due, in part, to faster progression to ESRD among African Americans. Anaemia is associated with a risk of kidney disease progression and is more prevalent among African Americans. The purpose of this study is to determine if anaemia is associated with progression to ESRD differently according to race. A retrospective cohort study of Cooperative Cardiovascular Project data for 87 693 Medicare beneficiaries >or=65 years old and ESRD free admitted to 4047 hospitals with acute myocardial infarction between February 1994 and June 1995 was conducted. Follow-up was collected through June 2004 for ESRD and mortality. Among 87 693 patients, 7.0% were African Americans and 50.1% females. African Americans had a higher prevalence of anaemia than whites (40.2% versus 26.7%, respectively; P < 0.001). Lower haematocrit was associated with higher ESRD rates after adjustment, and the association of haematocrit with ESRD did not vary according to race (P = 0.19). This association was strongest at the lowest baseline kidney function (GFR <15) with hazard ratios increasing 7-fold as haematocrit decreased from >or= 42% to <28%. In a nationally representative sample of patients with cardiovascular disease, anaemia was associated equally among African Americans and whites with an increased risk of ESRD.