Abnormalities of vascular endothelial function may contribute to increasedcoronary heart disease risk in UK Indian Asians

Objective-To test the hypothesis that abnormalities of endothelial function are present in Indian Asians and may contribute to their increased coronar y heart disease risk. Setting-Single centre in west London. Patients-26 Indian Asian and 18 European white healthy male subjects, aged 35 to 61 years recruited from general practice lists. Design-Brachial artery diameter responses to reactive hyperaemia and sublin gual glyceryl trinitrate were compared using high resolution ultrasound. Results-Mean (SEM) flow mediated, endothelium dependent dilatation was redu ced in Indian Asians compared with European whites, at 3.2 (0.8)% v 5.9 (1. 0)%, p = 0.03. In contrast, there were no significant differences in baseli ne brachial arterial diameter (4.6 (0.1) v 4.6 (0.1) mm, p = 0.65) or glyce ryl trinitrate induced dilatation (18.8 (1.5)% v 18.5 (1.7)%, p = 0.90) bet ween Indian Asians and European whites, respectively. Univariate analysis s howed that Indian Asian race was significantly associated with impaired flo w mediated dilatation (regression coefficient = -2.8 (1.3)%, p = 0.03), and in multivariate analysis, this relation was independent of both convention al coronary heart disease risk factors and markers of insulin resistance. Conclusions-Endothelial function is impaired in healthy UK Indian Asians co mpared with European whites, and the defect is not accounted for by major c oronary heart disease risk factors. Endothelial function may be modulated b y novel risk factors in Indian Asians.