Circadian aspects of motor activity in depressed patients.

Wrist motor activity was continuously monitored in 10 major unipolar depressed inpatients. Clinical state and motor activity parameters were studied. The data obtained at the beginning of the hospitalization, before the antidepressant treatment, were compared to chose found just before discharge. Time of day effect and subtypes of depression (endogenous versus non-endogenous) were considered. Motor retardation is related to both fluctuations of activity level and high number of 15 minute immobility epochs. Immobility parameters at night and during day were a good indicator of the severity of the depressive state. The temporal pattern of activity level was related to the subtype of depression.