Impact of 4 key behavioral strategies on BMI change in the Maine Youth Overweight Collaborative

Background and Purpose:

The health care setting, where providers see the majority of children and youth may be opportune for interventions to reduce and prevent obesity. The Maine Youth Overweight Collaborative (MYOC) adopted, as a framework for intervention, four key messages consisting of encouraging five (5) or more servings of fruits and vegetables daily; limiting screen time to two (2) hours or less daily; participating in at least one (1) hour or more of physical activity daily, and; avoiding (0) sugar-sweetened beverages, limiting fruit juice to one-half cup or less daily, and encouraging water and 3-4 servings of fat free milk daily, known as “5-2-1-0” . We describe the impact of MYOC on BMI z-score change using longitudinal chart review data.

Methods:

Chart reviews from patients ages 6-18 were gathered in 9 MYOC and 10 comparison sites; height and weight data were gathered for one year beginning 03/2007 and for all visits prior to start of MYOC (11/2004). Multilevel regression models were used to account for the clustered sampling plan, and control for pre-intervention growth trajectories in estimating impact of the intervention on change in BMI z-scores following initiation of MYOC.

Results:

Longitudinal data for 1178 intervention and 1260 comparison participants found no baseline differences in patient demographics. Baseline BMI z-scores were higher in MYOC versus comparison sites (0.61 vs 0.53) and rates of obesity (>95th) were higher in intervention (19%) vs comparison (15%)(P=0.03). Regression models of change in mean BMI z-scores indicate increasing trends pre-MYOC and significantly decreasing trends post-MYOC for subjects obese at baseline (pre-trend: 0.136; post -.267: P<0.0001). Significant decreases in trend were also seen for those overweight at baseline, and in the entire sample (Both P<0.0001). The declines were not significantly different for MYOC and comparison sites.

Conclusions:

Results indicate substantial declines in BMI z scores in this longitudinal cohort of 2438 children in Maine following initiation of MYOC in 2004, particularly among obese and overweight children. Similar declines are seen in both MYOC and control sites indicating that major determinants of overweight and obesity in youth may be primarily environmental and that the impact of MYOC alone may be minimal. Alternatively, the substantial spread of MYOC throughout the state may also have “contaminated” the comparison sites by encouraging 5210 interventions. The reductions in BMI z-scores may also have been aided by other community and school changes initiated through Healthy Maine Partnerships funded in 31communities statewide.