Reducing Waistlines for Obese Men

Lifestyle-based interventions in a clinical setting for obese patients were found to have modest reductions in waist circumference (WC) after a 2-year period compared with usual care, according to new study findings; however, the interventions were only effective for men. The findings of the PROACTIVE (Prevention and Reduction of Obesity through Active Living) trial were recently published online in Archives of Internal Medicine [doi:10.1001/archinternmed.2011.1972]. It has long been established that obesity increases the risk of chronic conditions and decreases quality of life, but according to the authors of the PROACTIVE trial, primary care physicians often fail to provide adequate counseling for these individuals due to a variety of factors, including time and money. In this study, the researchers sought to determine whether having a health educator at the site of the clinical practice working in conjunction with the primary care physician to counsel obese patients during a 24-month behaviorally based physical activity and diet program would have an overall impact on WC reduction. The study randomized 490 sedentary, obese adults at 3 family medicine clinics to receive either usual care or the lifestyle-based behavioral intervention. Physicians were instructed to counsel patients assigned to the usual care group in their typical manner and were told to continue meeting with the patients based on their standard schedule. Those patients in the 2-year behavioral intervention participated in individually tailored counseling sessions with a health educator assigned to the family clinic who used motivational interviewing techniques to work with participants. The intervention included 3 phases. First, the health educator worked with participants in one-on-one counseling sessions for 6 months to promote knowledge and skills aimed at increasing physical activity and healthy eating. The second 6-month phase encouraged participants to continue their current program, and in the final stage the duration of health educator counseling sessions was determined based on the participants’ WC and activity level. Participants included in the study were sedentary and participated in ≤1 planned activity a week. They had body mass index levels between 27 and 39, and had a WC ≥102 cm in men or ≥88 cm in women. The primary outcome of the study was the change in WC. Researchers identified other secondary outcomes as common metabolic risk factors, body fat percentage using bioelectrical impedance, and the calculated metabolic syndrome. At the conclusion of the study, researchers found that there was a significant main effect for WC change in the intervention group compared with those receiving usual care (P<.001). In addition, there was a greater mean reduction in WC for those in the intervention group than those who received the usual care at each follow-up visit of the study, and this finding remained statistically different at the 24-month period as well (mean, −0.9 vs 0.2 cm; P=.05). However, researchers did find that the effectiveness of the study was dependent on the sex of the participants. They found that, for men, there was a greater reduction in WC for those in the intervention group when compared with the usual care group for each follow-up visit, and this reduction remained statistically significant at 24 months (P=.049). At 24 months, men in the intervention group saw a mean reduction in WC of −1.6 cm compared with a mean in WC of 0.1 cm in the usual care group. However, for women, this greater reduction in WC was seen in the intervention group at the 6- and 12-month marks (P≤.01) but was no longer statistically different between the 2 groups at the 24-month mark. The study’s authors did find a significant main effect for change in WC in both men (P=.009) and women (P=.02) during the study. They concluded by acknowledging several limitations to their trial. For instance, there was a lack of objective measures of physical activity, and the study was not designed to test how dietary changes, increased physical activity, and weight loss contributed to the WC reduction or the metabolic syndrome.