Follow-up of a healthy lifestyle education program (the EdAl study): four years after cessation of randomized controlled trial intervention

BACKGROUND An important challenge of school-based childhood obesity (OB) intervention programs is understanding the maintenance of the effects after cessation of the intervention to overcome the limitations of follow-up studies. The aim of this study is to verify the sustainability of the benefits achieved at a 4-year follow-up of the post-Educació en Alimentació (EDAl) program intervention cessation by assessing the OB-related outcomes and lifestyles of 13- to 15-year-old adolescents. METHODS This paper describes a 4-year follow-up study after the cessation of a school-based randomized controlled intervention in adolescents (n = 349, intervention; n = 154, control) with baseline and 4-year follow-up data from high schools in Reus (intervention group), Salou, Cambrils and Vila-seca (control group). The outcomes are body mass index (BMI), BMI z-score, and OB prevalence according to the World Health Organization and International Obesity Task Force criteria and lifestyle data (obtained from questionnaires). RESULTS Compared with the control girls, the intervention girls showed reduced BMI z-scores (-0.33 units, p < 0.01) from baseline (2007) to the 4-year follow-up post-intervention (2014). Compared with the control boys, the intervention boys showed reduced OB prevalence (-7.7%; p = 0.02). Compared with the control boys, more boys in the intervention group (19% increase; p = 0.059) showed ≥4 h/week after-school physical activity (PA). A decrease in the consumption of dairy products, fruits and fish was observed in both groups. CONCLUSIONS At the 4-year post-intervention follow-up of the EdAl program, compared with the control groups, girls had lower BMI z-scores and boys had lower OB prevalence from the intervention. The encouragement in after-school PA was long-lasting and maintained after the cessation of the intervention, whereas healthy food habits must be further reinforced in adolescents. TRIAL REGISTRATION ISRCTN29247645 .