Motivational Interviewing to Treat Overweight Children: 24-Month Follow-Up of a Randomized Controlled Trial

BACKGROUND: Pediatrician-led motivational interviewing can be an effective way of controlling BMI in overweight children in the short term. Its long-term efficacy is unknown. The primary aim was to determine whether the short-term (12-month) impact of family pediatrician-led motivational interviews on the BMI of overweight children could be sustained in the long term (24 months), in the absence of any other intervention. METHODS: Children were recruited in 2011 by family pediatricians working in the province of Reggio Emilia, Italy, and randomly allocated to receive either 5 interviews delivered over a 12-month period or usual care. Eligible participants were all 4- to 7-year-old overweight children resident in the province of Reggio Emilia who had been receiving care from the pediatrician for ≥12 months. The primary outcome of this study was individual variation in BMI between the baseline visit and the 24-month follow-up, assessed by pediatricians not blinded to treatment group allocation. RESULTS: Of 419 eligible families, 372 (89%) participated; 187 children were randomized to receive intervention and 185 to usual care. Ninety-five percent of the children attended the 12-month follow-up, and 91% attended the 24-month follow-up. After the 12-month intervention period, BMI in the intervention group increased less than in the control group (0.46 and 0.78, respectively; difference −0.32; P = .005). At the 24-month follow-up, the difference had disappeared (1.52 and 1.56, respectively; difference −0.04; P = .986). CONCLUSIONS: The intervention lost its effectiveness within 1 year of cessation. Sustainable boosters are required for weight control and obesity prevention.