Lack of association between genetic variation in the beta 3-adrenergic receptor gene and insulin resistance in patients with coronary heart disease

The beta-adrenergic system plays a critical role in regulating lipolysis an d thermogenesis, Recent studies have suggested that a missense Trp6Arg muta tion in the beta(3)-adrenergic receptor gene is involved in visceral obesit y and insulin resistance. We investigated the effect of this mutation on in sulin resistance in patients with angiographically documented coronary hear t disease ([CHD] n = 137) and normal subjects (n = 188), plasma glucose and insulin responses to a 75-g oral glucose tolerance test and insulin resist ance measured by the insulin suppression test, were determined in 58 (42%) patients with CHD and 121 (64%) controls. The genotype and allele frequency of the beta(3)-adrenergic receptor did not differ between patients with CH D and controls. The blood pressure, body mass index (BMI), waist to hip rat io, fasting plasma glucose, insulin, and lipid, and plasma glucose and insu lin responses to the glucose load were relatively similar in subjects with and without the mutation in CHD and normal groups. The degree of insulin se nsitivity, ie, the steady-state plasma glucose concentration, was not signi ficantly different between subjects with and without the mutation in the CH D group (11.3 +/- 1.2, n = 11 v 11.9 +/- 0.6 mmol/L, n = 47, P = NS) and ce ntral group (8.4 +/- 0.7, n = 30 v 8.2 +/- 0.4 mmol/L, n = 91, P = NS). We conclude that Trp64Arg polymorphism of the beta(3)-adrenergic receptor gene does not likely play a major role in the development of CHD in the Chinese population, In addition, it appears to have no association with the insuli n resistance syndrome in either CHD or non-CHD subjects. Copyright (C) 1999 by W.B. Saunders Company.