Sleep quality and its association with delirium among veterans enrolled in Hospice

Objectives: The objectives of this study were to describe sleep quality and evaluate the association of sleep quality with delirium onset among patients enrolled in hospice. Design: The study utilized secondary data from a prospective, observational, longitudinal study. Setting: Veterans enrolled in hospice were recruited from the Portland Veterans Affairs Medical Center, Portland, Oregon. Participants: The cohort consisted of 105 patients, of whom 73% had at least one sleep measurement. Measurements: Sleep quality was measured with the Pittsburgh Sleep Quality Index. Delirium was measured with the Confusion Assessment Method. Other important variables were recorded from the medical record and/or longitudinal interviews with patients and their caregivers. Cox regression was used to estimate hazard ratios (HRs) to measure the association between sleep quality and delirium onset. Results: Of the patients who could be assessed, 44% had poor average sleep quality and 58% reported at least one episode of poor sleep. Overall, sleep quality did not appear to worsen as patients neared death although an increasing number of patients were unable to report on sleep quality. Poor sleep quality was associated with an increased risk of developing delirium, with an HR of 2.37 (95% CI: 1.50-3.74), for every one point worsening in the sleep quality score on a 4-point scale. Conclusions: Poor sleep quality was common among Veteran patients enrolled in hospice. These findings may help guide decision making between clinicians, patients, and families regarding the likely impact of sleep disturbance and may help identify patients at higher risk of developing delirium.