Preventing weight gain: one-year results of a randomized lifestyle intervention.

Background: Lifestyle interventions targeting prevention of weight gain may have better long-term success than when aimed at weight loss. Limited evidence exists about such an approach in the primary care setting.

Design: An RTC was conducted.

Setting/participants: Participants were 457 overweight or obese patients (BMI=25-40 kg/m(2), mean age 56 years, 52% women) with either hypertension or dyslipidemia, or both, from 11 general practice locations in The Netherlands.

Intervention: In the intervention group, four individual visits to a nurse practitioner (NP) and one feedback session by telephone were scheduled for lifestyle counseling with guidance of the NP using a standardized computerized software program. The control group received usual care from their general practitioner (GP).

Main Outcome Measures: Changes in body weight, waist circumference, blood pressure, and blood lipids after 1 year (dropout <10%). Data were collected in 2006 and 2007. Statistical analyses were conducted in 2007 and 2008.

Results: There were more weight losers and stabilizers in the NP group than in the general practitioner usual care (GP-UC) group (77% vs 65%; p<0.05). In men, mean weight losses were 2.3% for the NP group and 0.1% for the GP-UC group (p<0.05). Significant reductions occurred also in waist circumference but not in blood pressure, blood lipids, and fasting glucose. In women, mean weight losses were in both groups 1.6%. In the NP group, obese people lost more weight (-3.0%) than the non-obese (-1.3%; p<0.05).

Conclusions: Standardized computer-guided counseling by NPs may be an effective strategy to support weight-gain prevention and weight loss in primary care, in the current trial, particularly among men.

Trial Registration: The study was registered with the Netherlands Trial Register (NTR), www.trialregister.nl, study no. TC 1365.