Sleep in hospitalized medical patients, part 1: factors affecting sleep.

BACKGROUND Multiple factors lead to sleep disturbances in hospitalized medical patients. Inadequate sleep can lead to both psychological and physiological consequences. METHODS A PubMed search was conducted using the terms: ("sleep deprivation," "sleep," or "insomnia") and ("hospitalized," "inpatient," "critical illness," or "acute illness") to review the published data on the topic of sleep in hospitalized medical patients. The search was limited to English-language articles published between 1997 and 2008. Subsequent PubMed searches were performed to clarify the data described in the initial search, including the terms "hospital noise," "hospital environment," "obstructive sleep apnea," and "heart failure." RESULTS Few articles specifically addressed the topic of sleep in hospitalized medical patients. Data were limited to observational studies that included outcomes such as sleep complaints and staff logs of wakefulness and sleep. In Part 1, we review normal sleep architecture, and discuss how major medical disorders, the hospital environment, and medications can disrupt sleep during hospitalization. In Part 2, we will propose an evaluation and treatment algorithm to optimize sleep in hospitalized medical patients. CONCLUSIONS Hospitalization may severely disrupt sleep, which can worsen pain, cardiorespiratory status, and the psychiatric health of acutely ill patients. Like vital signs, the patient sleep quality reveals much about patients' overall well-being, and should be a routine part of medical evaluation.