Trial of prevention and reduction of obesity through active living in clinical settings: a randomized controlled trial

Arch Intern Med. 2012 Mar 12;172(5):414-24. doi: 10.1001/archinternmed.2011.1972. Epub 2012 Feb 27.


Background: The efficacy of physical activity with a healthful diet to reduce obesity is established; however, little is known about the translation of effective lifestyle strategies for obesity reduction in primary care settings.

Methods: We assessed the effectiveness of a 2-year behaviorally based physical activity and diet program implemented entirely within clinical practices to reduce obesity. A total of 490 sedentary, obese adults were randomized to usual care (n = 241) or to the behavioral intervention (n = 249). The usual care group received advice from their physicians about lifestyle as a strategy for obesity reduction. The behavioral intervention included individual counseling from health educators to promote physical activity with a healthful diet. The primary outcome was change in waist circumference (WC).

Results: A total of 396 participants completed the trial (80.8%). A significant main effect was observed for WC change within the intervention compared with usual care (P < .001) that was sustained at 24 months (mean [SE], -0.9 [0.4] vs 0.2 [0.4] cm; P = .05). Secondary analyses revealed significant main effects for change in WC in men (P = .009) and women (P = .02). In men, the mean (SE) reduction in WC at 24 months was greater with behavioral intervention compared with usual care (-1.6 [0.6] vs 0.1 [0.6] cm; P = .049). In women, the behavioral intervention was associated with differences in WC compared with usual care at 6 and 12 months (P ≤ .01) but not at 24 months (P = .10).

Conclusions: Behavioral intervention in clinical settings is associated with modest reductions in WC during a 2-year study in obese patients. However, the effectiveness of the intervention is restricted to men.

Trial registration: Identifier: NCT00665158.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Behavior Therapy / methods*
  • Body Mass Index
  • Diet*
  • Exercise / physiology*
  • Female
  • Humans
  • Life Style*
  • Male
  • Obesity / prevention & control*
  • Ontario
  • Patient Compliance / statistics & numerical data
  • Patient Satisfaction
  • Primary Health Care / methods
  • Treatment Outcome
  • Waist Circumference
  • Weight Loss*

Associated data