Ethnic differences in the prevalence of hypertension and proteinuria in NIDDM

There are large ethnic differences in both the prevalence of diabetes and the pattern of clinical complications, especially diabetic nephropathy and coronary heart disease. The aim of this study was to compare ethnic differences in the prevalence of two important risk factors, hypertension and proteinuria, among 1845 consecutive patients with non-insulin-dependent diabetes mellitus (NIDDM) undergoing annual complications assessment. Using a well-established database and systematic methods of data collection, information on clinical, demographic and laboratory variables was compared among seven ethnic groups: Anglo-Celtic (n = 896), Italian (n = 246), Greek (n = 209), Arabic (n = 147), Chinese (n = 131), Indian (n = 115) and Aborigine (n = 101). The odds ratios (OR) for developing hypertension (relative to Anglo-Celtic subjects) were lower in all ethnic groups, especially Arabs (OR = 0.4), Indians (OR = 0.4) and Aborigines (OR = 0.6). By contrast, the odds ratios for proteinuria (relative to Anglo-Celts) were consistently higher in all ethnic groups, e.g. Arabs (OR = 3.0) and Aborigines (OR = 3.1), even after correction for age, duration of diabetes and glycaemic control. Thus, relative to Anglo-Celtic patients, other ethic groups are less likely to have hypertension and more likely to have proteinuria. These findings may have important implications for understanding the ethnic differences in onset and progression of diabetic nephropathy.