Ethnic differences in mortality, end-stage complications, and quality of care among diabetic patients: a review.

OBJECTIVE To determine the influence of ethnic differences in diabetes care on inequalities in mortality and prevalence of end-stage complications among diabetic patients. The following questions were examined: 1) Are there ethnic differences among diabetic patients in mortality and end-stage complications and 2) are there ethnic differences among diabetic patients in quality of care? RESEARCH DESIGN AND METHODS A review of the literature on ethnic differences in the prevalence of complications and mortality among diabetic patients and in the quality of diabetes care was performed by systematically searching articles on Medline published from 1987 through October 2004. RESULTS A total of 51 studies were included, mainly conducted in the U.S. and the U.K. In general, after adjusting for confounders, diabetic patients from ethnic minorities had higher mortality rates and higher risk of diabetes complications. After additional adjustment for risk factors such as smoking, socioeconomic status, income, years of education, and BMI, in most instances ethnic differences disappear. Nevertheless, blacks and Hispanics in the U.S. and Asians in the U.K. have an increased risk of end-stage renal disease, and blacks and Hispanics in the U.S. have an increased risk of retinopathy. Intermediate outcomes of care were worse in blacks, and they were inclined to be worse in Hispanics. Likewise, ethnic differences in quality of care in the U.S. exist: process of care was worse in blacks. CONCLUSIONS Given the fact that there are ethnic differences in diabetes care and that ethnic differences in some diabetes complications persist after adjustment for risk factors other than diabetes care, it seems the case that ethnic differences in diabetes care contribute to the more adverse disease outcomes of diabetic patients from some ethnic minority groups. Although no generalizations can be made for all ethnic groups in all regions for all kinds of complications, the results do implicate the importance of quality of care in striving for equal health outcomes among ethnic minorities.