Increased incidence of sleep apnea in psychiatric outpatients.

BACKGROUND: The rate of mood disorders in patients in sleep centers has been the subject of many studies, yet little has been published on the incidence of sleep apnea in psychiatric patients. METHODS: A retrospective chart review was performed on 330 consecutively seen psychiatric outpatients. Medication history, demographics, and the results of patients' most recent Quick Inventory of Depressive Symptomatology (QIDS) were collected. Patients were checked for a history of apnea through a review of session notes and the results of any polysomnogram that the patient had on file. RESULTS: Of the patients studied, 9.7% were positive for sleep apnea. They required a significantly higher number of medications (3.2 vs 2.4; P < .001). They also scored significantly higher on 3 items on the QIDS: late insomnia (1.0 vs 0.55; P < .01), reduced energy level (1.2 vs 0.76; P < .02), and decreased general interest (1.0 vs 0.64; P < .04). Middle age in men (age 45 to 64) and higher body mass index both in men and women were also associated with a higher frequency of sleep apnea. CONCLUSION: Sleep apnea is more prevalent in psychiatric outpatients than in the general population. Identification of this comorbid condition will likely result in better treatment outcomes.