Can physical activity explain the differences in insulin levels and fibrinolytic activity between young indo-origin and European relatives of patients with coronary artery disease?

Abstract

Summary In a comparison of young Indo-origin (IO) and young North European (NE) male relatives of patients with angiographically demonstrated coronary artery disease (CAD), we found a significant difference in daily leisure physical activity between the two groups, as measured both by a questionnaire and by pedometer readings. Mean daily walking distance by pedometer was 1.8 Km per day for the IO group and 2.4 Km per day for the NE group (P=0.007). Physical activity was an independent predictor of tissue plasminogen activator (t-PA) activity and of plasminogen activator inhibitor-1 (PAI-1) activity in both groups on multivariate analysis. On univariate analysis, physical activity (pedometer score) was negatively correlated with fasting serum insulin concentration (r=0.49 for IO and r=0.54 for NE subjects) and with PAI-1 activity (r=0.47 for IO, r=0.42 for NE), and positively correlated with t-PA activity (r=0.38 for IO, r=0.34 for NE). Mean serum insulin and lipoprotein (a) concentrations, and mean PAI-1 activity were significantly raised in IO as compared to NE subjects; however, when adjusted for pedometer scores the inter-ethnic differences for insulin concentration and PAI-1 activity, but not for Lp(a) concentration, were greatly reduced. Different levels of physical activity may contribute significantly to inter-ethnic differences in metabolic and fibrinolytic function.