Four-year follow-up of school-based intervention on overweight children: the KOPS study

Objective: To evaluate the 4‐year outcome of a school‐based health promotion on weight status as part of the Kiel Obesity Prevention Study (KOPS). Research Methods and Procedures: Within a cluster‐sampled quasi‐randomized controlled trial, 1764 children at 6 and 10 years of age were assessed between 1996 and 2005 in 32 primary schools in Kiel, North Germany. Six nutrition units followed by 20‐minute running games were performed within the first year at school. Prevalence, incidence, and remission of overweight were main outcome measures. Results: The 4‐year change in BMI was +11.6%, with increases in prevalence of overweight and obesity from 5.2% to 11.1% and 3.9% to 5.1%, respectively. Cumulative 4‐year incidence of overweight and obesity was 9.2% and 3.1%, respectively. Intervention had no effect on mean BMI. The effect on prevalence was significant in children from families with high socioeconomic status odds ratio (OR), 0.35; 95% confidence interval (CI), 0.14 to 0.91] and marginally significant in children of normal‐weight mothers (OR, 0.57; 95% CI, 0.33 to 1.00). Cumulative 4‐year incidence of overweight was lower only in intervention children from families with high socioeconomic status (OR, 0.26; 95% CI, 0.07 to 0.87). Remission of overweight was most pronounced in children of normal‐weight mothers (OR, 5.43; 95% CI, 1.28 to 23.01). Prevalence of underweight was unchanged. The intervention had minor but favorable effects on lifestyle. Discussion: A school‐based health promotion has sustainable effects on remission and incidence of overweight; it was most pronounced in children of normal‐weight mothers and children from families with high socioeconomic status. There was no effect on obesity. The data argue in favor of additional measures of prevention.