The impact of BMI on direct costs in Children and Adolescents: empirical findings for the German Healthcare System based on the KiGGS-study

Childhood obesity is a growing public health burden. Among German children and adolescents, 15% are overweight (including obese) and 6.3% are obese according to a national reference. This is the first German study to assess aspects of the economic burden associated with overweight and obesity in children and adolescents based on a representative cross-sectional survey. Based on the German Interview and Examination Survey for Children and Adolescents (KiGGS), direct costs induced by utilisation of healthcare services (physician and therapist visits, hospital stays) were assessed using a bottom-up approach. To investigate the impact of body mass index (BMI) on costs, univariate analyses were performed and multivariate generalised mixed models were estimated. Average annual total costs were estimated to be a,not sign442 (95% CI [402-486]). Bivariate analysis showed considerable differences between BMI groups in physician costs, but not for hospital or therapist costs. High socioeconomic status, residence in west Germany and underweight had a significant negative impact on total costs in multivariate analysis. The effect of overweight on total costs is positive but not significant; neither is the effect of obesity. However, overweight and obese children exhibit significantly higher physician costs and a higher probability of being high utilisers of healthcare services. The economic implications of overweight and obesity are, to some extent, already visible in childhood. The results suggest that obese children should be classified as priority group for prevention. Despite limitations, this study provides important information concerning the relevance of childhood obesity as a health problem.