[Effectiveness of a therapeutic practice on overweight in primary care]

To evaluate the effectiveness of an intervention program on overweight to achieve a minimum decrease of 5% or a optimum of 10% of initial weight a year, and to identify the factors associated with slimming.

Randomized controlled trial.

Urban health centre.

Overweight subjects over 18 years old (n=169), wanting treatment or referred by their doctor. They were randomly assigned to the intervention (n=95) or control (n=70) group.

Intervention group: yearly program with consultations every 15-21 days, using a low calorie diet, prescribing physical exercise, changing of habits and health education.

low calorie diet, seen 3 times/year.

The minimum weight loss was achieved in 6 months by 37.9% of the intervention group and by 21.4% of the control group. At one year, 45.3% of the intervention subjects and 24.3% of the control group reached this objective. The optimum loss of 10% was higher in the intervention group, but was not statistically significant. The minimum objective was associated with the intervention group (OR=4.5 [1.36-14.49]). It was also associated to the number of visits during therapy (OR=1.85 [1.50-2.29]) and diabetes (OR=10 [1.13-90.9]).

The intervention group had a loss of 5% of initial weight in the first 6 months, 16.5% more than the control group, and 21% more in one year. Achieving the minimum objective was associated with the intervention group, the number of visits and the diagnosis of diabetes.