How should we measure delayed sleep phase shift in severe, refractory obsessive-compulsive disorder?
Drummond LM., Wulff K., Rani RS., White S., Mbanga-Sibanda J., Ghodse H., Fineberg NA.
OBJECTIVE: A previous study, based upon direct nursing observations, showed almost half of a cohort of inpatients with severe, enduring OCD also suffered from delayed sleep phase shift. Males, younger patients and those with more severe symptoms were most likely to be affected. However, the ward environment may have had a direct effect on sleeping patterns. In this study we compared the accuracy of actigraphic measurements with that of the "gold standard" of direct nursing observation, and other clinical sleep scales. We postulated that actigraphy would prove a reliable, acceptable, and valid alternative. METHODS: All patients admitted over 29 months to a specialized treatment unit for severe, chronic refractory OCD were invited to participate. We collected demographic data, clinical measures of OCD and depressive symptom severity, self-rated measures of social and occupational disability and sleep, nursing records based upon direct observation of sleep onset and duration, and actigraphy records. RESULTS: Evaluable data was obtained from 36 patients (22 males) with an average age of 37 years and profound OCD symptoms measured by the Yale-Brown Obsessive-Compulsive Scale. According to direct nursing observation, 12 patients (33%) showed delayed sleep phase shift. Actigraphic recordings demonstrated good agreement (kappa = 0.63) with nursing observation as did the St George's Insomnia Questionnaire (kappa = 0.66). CONCLUSION: This study demonstrates that actigraphy is a reliable method of recording sleep/activity cycles in severe, enduring OCD.