Motor activity and severity of depression in hospitalized prepubertal children

Objective: To determine whether there is an association between activity levels and the severity and nature of depressive symptoms. Method: Locomotor activity was quantified in 27 consecutively selected hospitalized prepubertal children. Activity was measured in 5-minute epochs over a period of 72 hours using belt-worn monitors. Depressive symptoms were rated using the Children's Depression Rating Scale-Revised, the Children's Depression Inventory, and an observer rating scale for nursing staff. Results: Measures of reduced daytime activity correlated with scores on the Children's Depression Rating Scale and the observer rating scale, but not the Children's Depression Inventory. Stepwise regression indicated that the strongest association occurred between a composite measure of severity, age, and percentage of low-level diurnal activity periods (r = .724, p < .0005). Activity measures correlated with clinical ratings of sadness, low self-esteem, anhedonia, and physical complaints, and to a lesser degree with ratings of hypoactivity, fatigue, and dow speech. Conclusions: Reduced levels of activity correlated significantly with clinical ratings of depressive severity across diagnostic groups. The development of objective measures of depressive severity may have prognostic and therapeutic implications.