Publications

Abstract

Background:Sympathetic activation is an important metabolic adaptation limiting weight gain. Propensity of weight gain associated with beta-blocker therapy in the obese modern population is unknown.Objective:To determine whether chronic beta-blocker therapy reduces energy expenditure (EE) and increases body weight.Methods:We undertook (i) a mechanistic study comparing EE, diet-induced thermogenesis and habitual activity between healthy volunteers (n=11) with uncomplicated hypertension treated with a beta-blocker and anthropometrically matched controls (n=19) and (ii) three cross-sectional studies comparing body weight, body mass index (BMI) and waist circumference between beta-blocker treated and untreated patients from ambulatory patients attending (a) diabetes outpatient clinic (n=214), (b) hypertension outpatient (n=84) and (c) participants in a multi-centre type 2 diabetes trial (ADVANCE) (n=11140).Results:Among weight-matched beta-blocker users, diet-induced thermogenesis, fat oxidation rate and weekly habitual activity were lower by 50% (P<0.01), 32% (P=0.04) and 30% (P<0.01), respectively, compared with controls. In beta-blocker treated patients, the adjusted mean body weight was 9.2+/-1.2 kg (P=0.0002) higher among those attending the diabetes clinic, 17.2+/-3.2 kg (P=0.004) higher among those attending the hypertension clinic and 5.2+/-0.7 kg (P=0.0003) higher at baseline among participants in the ADVANCE trial compared with patients not treated with beta-blockers. BMI displayed a similar difference.Conclusions:EE is reduced and body weight increased in chronic beta-blocker users. We hypothesise that chronic beta-blockade causes obesity by blunting EE.International Journal of Obesity advance online publication, 8 February 2011; doi:10.1038/ijo.2010.284.