title: Metabolic sequelae of β-blocker therapy: weighing in on the obesity epidemic?
abstract: BACKGROUND
  Sympathetic activation is an important metabolic adaptation limiting weight gain. Propensity of weight gain associated with β-blocker therapy in the obese modern population is unknown.
  
  
  OBJECTIVE
  To determine whether chronic β-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 β-blocker and anthropometrically matched controls (n=19) and (ii) three cross-sectional studies comparing body weight, body mass index (BMI) and waist circumference between β-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 β-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 β-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 β-blockers. BMI displayed a similar difference.
  
  
  CONCLUSIONS
  EE is reduced and body weight increased in chronic β-blocker users. We hypothesise that chronic β-blockade causes obesity by blunting EE.
authors.affiliation: Department of Endocrinology, St Vincent's Hospital, Sydney, New South Wales, Australia.
authors.forename: P
authors.initials: P
authors.lastname: Lee
authors.forename: A-P
authors.initials: AP
authors.lastname: Kengne
authors.forename: J R
authors.initials: JR
authors.lastname: Greenfield
authors.forename: R O
authors.initials: RO
authors.lastname: Day
authors.forename: J
authors.initials: J
authors.lastname: Chalmers
authors.forename: K K Y
authors.initials: KK
authors.lastname: Ho
mesh_terms: D015502:Absorptiometry, Photon; D050154:Adiposity / Q000187:drug effects*; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000009:adverse effects*; D000368:Aged; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000009:adverse effects*; D001315:Australia / Q000453:epidemiology; D015992:Body Mass Index; D001835:Body Weight / Q000187:drug effects*; D016022:Case-Control Studies; D004734:Energy Metabolism / Q000187:drug effects*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000139:chemically induced* / Q000453:epidemiology / Q000378:metabolism; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D022722:Thermogenesis / Q000187:drug effects; D055105:Waist Circumference
chemical_list: D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents