Lifestyle Intervention to Prevent Regain after Weight Loss

Overweight or obesity is a worldwide problem. An increased body mass index is associated with higher mortality, the development of coronary vascular disease, type 2 diabetes mellitus, certain types of cancer, gastrointestinal diseases, and arthritis. The impact of these diseases on healthcare costs highlights the need for strategies to address the problem, according to researchers. Previous studies have shown that lifestyle interventions, which include a nutritional and a physical activity component, are crucial to weight loss. Lifestyle programs such as the Diabetes Prevention Program and the Diabetes Prevention Study showed weight loss of 4 kg and 3 kg, respectively, after 3 years. The weight loss was accompanied by improvements in cardiovascular risk factor levels. However, the researchers noted, weight regain after weight loss is a common problem; little is known about the long-term effects in the primary care setting. Guidelines for general practitioners (GPs) treating patients with hypertension and dyslipidemia include lifestyle advice. GPs who do not offer lifestyle advice cite barriers for such counseling: lack of time, lack of patient compliance, insufficient knowledge about the subject, and lack of evidence-based interventions. Hypothesizing that a solution to this problem would be to delegate lifestyle counseling to nurse practitioners (NPs), researchers recently conducted a study to determine whether structured lifestyle counseling by NPs, compared with usual care by GPs (GP-UC) in overweight and obese patients, would prevent further weight gain. The results were reported in Archives of Internal Medicine [2011; 171(4):306-313]. The study enrolled 457 participants 40 to 70 years of age in a general practice setting; inclusion criteria included body mass index between 25 and 40 (weight in kilograms divided by 8 in meters squared) and either hypertension and/or dyslipidemia. Exclusion criteria included diabetes mellitus, hypothyroidism, pregnancy, liver or kidney disease, current treatment for malignant disease, severely shortened life expectancy, mental illness, and addiction to alcohol or drugs. The participants were randomized to the NP group (n=225) or the GP-UC group (n=232). The lifestyle intervention in the NP group was 4 individual visits and 1 feedback session by telephone the first year, and 1 individual visit and 2 feedback sessions in the next 2 years. Elements of behavioral counseling such as individual goal setting, monitoring using food diaries and pedometers, and addressing barriers for changes in lifestyle. The GP-UC group received usual care from their physician. The primary aim of the intervention was to prevent weight gain; main outcome measures were changes in body weight, waist circumference, blood pressure, and fasting glucose and blood lipid levels after 3 years. At the 3-year follow-up, there were no differences in mean weight change between the 2 groups (−1.2% and −0.6%, respectively); approximately 60% of the participants in both groups had lost weight or remained at the same weight during the follow-up period. There was no difference between the 2 groups for lipid levels and blood pressure, but there was a significant difference for mean fasting glucose levels (NP group, −0.02 mmol/L; GP-UC group, 0.10 mmol/L; P=.021). In contrast to the results after 3 years, the percentage mean weight loss after 1 year did differ between the 2 groups (NP group, −2.2%; GP-UC group, −0.7%; P=.02). There were more weight losers and stabilizers after 1 year in the NP group compared with the GP-UC group (80% vs 64%; P=.001). The percentages of those who regained lost weight were similar between the 2 groups after 1 year (14% for the NP group and 15% for the GP-UC group). In summary, the researchers stated that “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.”