Comparative Effectiveness of Clinical Intensive Behavior Therapy for Obese Adults

Background: About 1 in 3 adults are obese in the United States, but the delivery of clinical weight loss counseling is infrequent. The Centers for Medicare & Medicaid Services began reimbursing for intensive behavior therapy (IBT) for obese adult beneficiaries in late 2011, but the real-world effectiveness of IBT has not been rigorously evaluated. This study compared weight change over 1 year between obese adult patients who did and did not receive IBT. Methods: A retrospective cohort of obese, adult virtual data warehouse members from the Marshfield Clinic Health System was assembled. Two groups were compared: adult patients who had ≥ 1 or more IBT visits versus those who had no IBT visits. The comparison group was matched on body mass index (BMI), age, sex and health care coverage. The primary outcome was body weight over 1 year. Weight loss surgery patients were excluded. Results: There were 107 patients exposed to IBT (~1% of those eligible) and 320 in the matched unexposed group. Patients who received IBT were 79% female and 72% elderly, with a mean (standard deviation) baseline BMI of 39.8 (7.4) kg/m2. IBT patients completed a median of 5 visits over 1 year, with visits being led predominantly by registered dietitians. Visit attendance dropped quickly though, with just 1% of IBT patients completing all 22 allotted visits. Body weight in the matched comparison group remained stable over 1 year, whereas IBT patients lost 3.9 (8.2) kg (P \u3c 0.001). Conclusion: Clinic-based IBT was moderately effective, as participants lost about 4% of their baseline weight over 1 year, or about 1 additional BMI unit. As expected, those who did not participate in IBT did not lose weight. But program participation and retention was quite low, as the relatively few patients exposed to IBT also completed very few of their allowable IBT visits, even after accounting for 6-month restrictions on program eligibility. To impact population level obesity, more research is needed on how to attract and engage obese adults in clinical weight management programs