Abstract P130: Weight Maintenance after a Worksite Nutrition and Exercise Program: A Randomized Controlled Trial

Abstract

Background: To address rising healthcare costs associated with obesity, many employers are providing programs to help employees lose weight and make lifestyle changes. Improving health outcomes and reducing costs will depend on whether employees sustain these changes, but few studies have evaluated worksite interventions to maintain a reduction in weight and cardiovascular risk factors over time. Methods: At a large hospital in Boston, MA, we conducted a randomized controlled trial to determine if a 9-month maintenance program immediately following a 10-week team-based worksite exercise and nutrition program would improve weight and cardiovascular risk factor outcomes at 1 year. In 2008, 330 employees from 24 teams completed a 10-week program and were randomized by team to the maintenance intervention or control (usual care) for 9 months. The maintenance intervention included both 1) Internet support with a website for individualized goal-setting and self-monitoring of weight and exercise and 2) minimal personal support with optional individual nutrition and exercise training sessions. Main outcome measures were weight loss, percentage weight loss, waist circumference, fasting lipids, and blood pressure at 1 year. For participants who did not follow up, we used a baseline observation carried forward method for 1 year outcomes. We used random-effects regression models adjusted for clustering within team, and the intervention effect was modeled as the interaction of study arm and time. Results: At 1 year, 238 subjects (72%) completed follow-up assessments. Mean baseline BMI was 27.6 and did not differ between intervention and control. Compared to baseline, both groups lost weight during the 10-week program and maintained 65% of weight loss at 1 year (p<.001). There was no difference in weight loss between intervention and control groups at end of the 10-week program (4.8 lbs vs. 4.3 lbs, p=.53 for group x time interaction) or end of maintenance at 1 year (3.4 lbs vs. 2.5 lbs., p=.40 for group x time interaction). All subjects had significant reductions in percentage weight loss, waist circumference, total cholesterol, and LDL cholesterol at 1 year but did not differ by group. Conclusions: A 10-week worksite nutrition and exercise program resulted in significant reductions in weight and cardiovascular risk factors at 1 year, and participation in an Internet-based maintenance program did not improve these outcomes. Worksite programs to maintain weight loss and lifestyle changes may require more resource-intensive behavioral counseling or incentives to engage participation and improve long-term effectiveness.