[Significance of gender of obese children and body weight of parents and siblings for the results of the treatment of obesity in childhood].

We studied the influence of family size, family history of obesity, and the obese children's sex on the short and medium term outcome of an obesity therapy in children aged 10.7 +/- 3 years with mean percentage overweight of 41.4 +/- 16.9%. Family parameters such as obesity on other family members, single child families, and sex of the obese children did not influence the decision to stop or to complete therapy. Boys were more successful in weight reduction than girls both after 3-6 months and after 3-5 years; the difference being not significant, however. Children without family history initially were significantly less overweight than those with familial obesity, and they exhibited the best short and medium term results. Children of obese families initially were the fattest ones. They reduced their weight more than average, but they tended to regain weight during the following 3-5 years, reaching the highest levels of overweight after that time. Children without family history of obesity did not regain weight, however. Thus even after good short term results obese children of obese parents should be regarded at risk for relapse and should be checked for years after therapy to prevent weight regain.