Objective: Within the past decades prevalence rates for obesity among children and adolescents have increased in different populations. The hypothesis of this study is that the degree of adiposity in clinical study cohorts of extremely obese children and adolescents increased within the past decade.
Design: In six different study cohorts of the time period from 1985-1995 body mass indices (BMIs) of obese children and adolescents who were treated as inpatients at a specialized children's hospital were evaluated. For this purpose body heights, body weights, ages and sex of all inpatients of three referring agencies were retrospectively assessed biannually.
Results: In these six cohorts a significant BMI-increase from 1985-1995 of 1.9 kg/m2 (P < 0.0001) for constant sex, age and referring agencies was found: Comparisons of the quartiles and the ninth decline in both sexes did not show any systematic increase at the first quartile. In contrast, BMI-increases at the ninth decile were approximately 5 kg/m2 for males and 2.5 kg/m2 for females.
Conclusion: Within the decade studied a significant BMI-increase was detectable in this clinical population. This effect is especially discernible in the most extreme weight groups and in males.