Preventing weight gain by lifestyle intervention in a general practice setting - three-year results of a randomized controlled trial

Background: Weight regain after initial loss of weight is common, which indicates a need for lifestyle counseling aimed at preventing weight gain instead of weight loss. This study was conducted to determine whether structured lifestyle counseling by nurse practitioners (NPs) group compared with usual care by general practitioners (GP-UC) in overweight and obese patients can prevent (further) weight gain.

Methods: A randomized controlled trial in 11 general practice locations in the Netherlands of 457 patients (body mass index, 25-40 [calculated as weight in kilograms divided by height in meters squared]; mean age, 56 years; 52% female) with either hypertension or dyslipidemia or both. The NP group received lifestyle counseling with guidance of the NP using a standardized software program. The GP-UC group received usual care from their GP. Main outcome measures were changes in body weight, waist circumference, blood pressure, and fasting glucose and blood lipid levels after 3 years.

Results: In both groups, approximately 60% of the participants achieved weight maintenance after 3 years. There was no significant difference in mean (SD) weight change and change of waist circumference between the NP and GPUC groups (weight change: NP group, -1.2% [5.8%], and GP-UC group, -0.6% [5.6%] [P=.37]; and change of waist circumference: NP group, -0.8 [7.1] cm, and GP-UC group, 0.4 [7.2] cm[P=.11]). A significant difference occurred for mean (SD) fasting glucose levels (NP group, -0.02 [0.49] mmol/L, and GP-UC group, 0.10 [0.53] mmol/L [P=.02]) (to convert to milligrams per deciliter, divide by 0.0555) but not for lipid levels and blood pressure.

Conclusions: Lifestyle counseling by NPs did not lead to significantly better prevention of weight gain compared with GPs. In the majority in both groups, lifestyle counseling succeeded in preventing (further) weight gain.