The representation of early onset depression by ICD-9 and ICD-10 categories

Concepts of affective disorders have not received substantial validation in childhood and adolescence even after the theoretical separation between neurotic and endogenous depression was changed. The aim of this study was to assess differences in children and adolescents with neurotic and endogenous depression according to ICD-9 and depression according to ICD-10 with regard to the severity of different symptoms as well as anamnestic and psychosocial risk factors.

Data of 33 and 88 patients (classified according to ICD-9 and ICD-10, respectively) with a confirmed diagnosis of depression were included. In a standardized study protocol, sociodemographic data, family history, psychopathological symptoms and psychosocial and environmental factors were analyzed.

Patients diagnosed with endogenous depression more frequently had a positive family history of psychiatric disorders and had more comorbid symptoms in comparison to those with neurotic depression. Group comparisons of the ICD-9 and ICD-10 demonstrated fewer abnormal psychosocial and environmental factors and fewer affective symptoms in the ICD-9 sample. Logistic regression revealed predictors for endogenous depression in the ICD-9 sample and severe depression in the ICD-10 sample.

Neurotic depression might represent a subthreshold depression diagnosis compared with endogenous depression. The present study was limited by small and different sample sizes and the fact that dysthymia was not classified within the ICD-10 diagnosis.