Telecoaching plus a portion control plate for weight care management: a randomized trial

BACKGROUND: Obesity is a leading preventable cause of death and disability and is associated with a lower health-related quality of life. We evaluated the impact of telecoaching conducted by a counselor trained in motivational interviewing paired with a portion control plate for obese patients in a primary care setting. METHODS: We conducted a randomized, clinical trial among patients in a primary care practice in the midwestern United States. Patients were randomized to either usual care or an intervention including telecoaching with a portion control plate. The intervention was provided during a 3-month period with follow-up of all patients through 6 months after randomization. The primary outcomes were weight, body mass index (BMI),waist circumference, and waist to hip ratio measured at baseline, 6, 12, 18, and 24 weeks. Secondary outcomes included measures assessing eating behaviors, self-efficacy, and physical activity at baseline and at 12 and 24 weeks. RESULTS: A total of 1,101 subjects were pre-screened, and 90 were randomly assigned to telecoaching plus portion control plate (n = 45) or usual care (n = 45). Using last-value carried forward without adjustment for baseline demographics, significant reductions in BMI (estimated treatment effect -0.4 kg/m(2), P = .038) and waist to hip ratio (estimated treatment effect -.02, P = .037) at 3 months were observed in the telecoaching plus portion control plate group compared to usual care. These differences were not statistically significant at 6 months. In females, the telecoaching plus portion control plate intervention was associated with significant reductions in weight and BMI at both 3 months (estimated treatment effect -1.6 kg, P = .016 and -0.6 kg/m(2), P = .020) and 6 months (estimated treatment effect -2.3 kg, P = .013 and -0.8 kg/m(2), P = .025). In males, the telecoaching plus portion control intervention was associated with a significant reduction in waist to hip ratio at 3 months (estimated treatment effect -0.04, P = .017), but failed to show a significant difference in weight and BMI. CONCLUSION: Telecoaching with a portion control plate can produce positive change in body habitus among obese primary care patients; however, changes depend upon sex. TRIAL REGISTRATION: ClinicalTrials.gov NCT02373878, 13 February 2015. https://clinicaltrials.gov/ct2/show/NCT02373878. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13063-015-0880-1) contains supplementary material, which is available to authorized users.