Measuring psychomotor agitation by use of an actimeter: a pilot study

Background: Psychomotor agitation is variably defined, with differing emphases on subjective and motor components. We assess the utility of an actimeter to inform us about aspects of the motor component. Methods: A wrist actimeter measured motor activity of three inpatients with agitated depression. Results: For each patient, diurnal activity patterns were observed, with activity generally elevated in mornings and late afternoons. Each patient also evidenced a clear decline in motor activity in the mid-evening, with little or no activity recorded during ‘sleep’ hours. Thus, psychomotor agitation (like motor activity) appears to require a conscious state. Limitations: Actimeters measure any baseline activity together with any superimposed movement component (which may range from movement changes to medication effects), making it difficult to disentangle components. We studied few patients and for brief intervals.