Bipolar disorder in children and adolescents in Germany: national trends in the rates of inpatients, 2000-2007

Objectives: Increasing admission and prevalence rates of bipolar disorder (BD) are a matter of controversy in international child and adolescent psychiatry. We seek to contribute to this discussion by presenting data obtained in a population of German children and adolescents. Methods: Nationwide, whole population changes in inpatient admissions of BD and other psychiatric disorders between 2000 and 2007 were analyzed in individuals aged up to 19 years using registry data from the German Federal Health Monitoring System. Results: Inpatient admissions for BD in individuals aged up to 19 years increased from 1.13 to 1.91 per 100,000 or 68.5% between 2000 and 2007 (odds ratio: 1.69; 95% confidence interval: 1.41-2.02), with a nonsignificant decline in children less than 15 years and the largest relative increase in adolescents aged 15-19 years. Inpatient rates for depressive disorders increased by 219.6% and for hyperkinetic disorder by 111.3%. Conduct disorders increased by 18.1%, considerably less than the 38.1% general rise for all mental disorders in children and adolescents. The only significant decline in a diagnostic category occurred for psychotic disorders (-11.8%). BD inpatient admission represented only 0.22% of all mental disorder admissions in 2000 and 0.27% in 2007. Conclusions: An elevation of inpatient admissions of BD in Germany in adolescents was detected, exceeding the general trend for increased mental disorder admissions. The results may indicate a higher clinical awareness and appreciation of mood symptoms at earlier ages and, in part, a reconceptualization of previously diagnosed psychotic disorders in youth. However, a diagnosis of BD in youngsters is still extremely rare in Germany. Diagnoses were based on the judgment of the treating physician. A correction for multiple admissions in the data set is not possible.