A Health-Literacy Intervention for Early Childhood Obesity Prevention: A Cluster-Randomized Controlled Trial

Abstract

Background and objectives: Children who become overweight by age 2 have greater risk of long-term obesity and health problems. The study aim was to assess the effectiveness of a primary care-based intervention on the prevalence of overweight at age 24 months.

Methods: In a cluster-randomized trial, sites were randomly assigned to the Greenlight intervention or an attention-control arm. Across 4 pediatric residency clinics, we enrolled infant-caregiver dyads at the 2-month well-child visit. Inclusion criteria included parent English- or Spanish-speaking and birth weight ≥1500 g. Designed with health-literacy principles, the intervention included a parent toolkit at each well-child visit, augmented by provider training in clear-health communication. The primary outcome was proportion of children overweight (BMI ≥85th percentile) at age 24 months. Secondary outcomes included weight status (BMI z score).

Results: A total of 459 intervention and 406 control dyads were enrolled. In total, 49% of all children were overweight at 24 months. Adjusted odds for overweight at 24 months (treatment versus control) was 1.02 (95% confidence interval [CI]: 0.63 to 1.64). Adjusted mean BMI z score differences (treatment minus control) were -0.04 (95% CI: -0.07 to -0.01), -0.09 (95% CI: -0.14 to -0.03), -0.19 (-0.33 to -0.05), -0.20 (-0.36 to -0.03), -0.16 (95% CI: -0.34 to 0.01), and 0.00 (95% CI -0.21 to 0.21) at 4, 6, 12, 15, 18, and 24 months, respectively.

Conclusions: The intervention resulted in less weight gain through age 18 months, which was not sustained through 24 months. Clinic-based interventions may be beneficial for early weight gain, but greater intervention intensity may be needed to maintain positive effects.

Trial registration: ClinicalTrials.gov NCT01040897.

Keywords: CI; Infants; NYU; New York University; Supplemental Nutrition Program for Women; UM; UNC; University of Miami; University of North Carolina at Chapel Hill; VUMC; Vanderbilt University Medical Center; WCV; WHO; WIC; World Health Organization; and Children; confidence interval; well-child visit.

Conflict of interest statement

POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose.

Copyright © 2021 by the American Academy of Pediatrics.

Figures

FIGURE 1

Overweight status (BMI >85th percentile) and BMI z score at each age, intervention versus control. Intervention effect estimates, from longitudinal regression analyses of overweight status (BMI ≥85th percentile) and BMI z score, between 4 and 24 months. All analyses are adjusted for baseline covariates as described in the Analyses section. The panels on left reveal the differences between the 2 intervention sites and the 2 control sites. The panels on the right reveal the site-specific differences in growth trajectories, with the larger of the 2 control sites (UNC) as referent. We capture site and intervention effects, with adjusted odds ratios for the binary outcome (overweight status) and adjusted mean differences for the continuous outcome (BMI z score). We display age-specific point estimates and CIs. The P values in the lower right corner of each plot correspond to the null hypothesis that growth trajectories are equal overall (across ages). To the extent that trajectories are not equal, P values are small. Two sites (NYU, VUMC) were randomly assigned to receive the intervention, and 2 sites (UM, UNC) were assigned to receive the active control.