Risk factors for chronic insomnia following hospitalization.

AIM: This paper reports a study whose purpose was to determine whether there is an increase in the incidence of chronic insomnia following hospitalization and, if so, to identify patients at risk.
BACKGROUND: The consequences of difficulty sleeping in hospital have received scant attention from clinicians or researchers. Implicit in this lack of interest is the assumption that difficulty in sleeping is a transient reaction to hospitalization that will resolve on discharge, an assumption not empirically supported. It has been argued that in susceptible people this type of temporary disruption to sleep can be the catalyst for the development of chronic insomnia.
METHOD: Established sleep and depression rating instruments were used to monitor the sleep of 57 cardiac and 29 orthopaedic patients after elective surgery (n = 86), recruited through a hospital preadmission clinic.
RESULTS: Preadmission chronic insomnia of 10% was consistent with general population prevalence estimates of 6-12%. Three months after discharge the incidence had almost doubled to 19%. Sixty-one per cent of this variance could be explained by hyperarousal, sleep hygiene issues, and dysfunctional cognitions about sleep. Depression was found to be a salient predictor but not an independent risk factor. Age, sex, and hospital-related data, such as score for difficulty sleeping in hospital, proved to be statistically insignificant.
CONCLUSIONS: The results support the role of hyperarousal and dysfunctional sleep attitudes and behaviours as stronger predictors of chronic insomnia than patient demographics or environmental issues. Given that most of the patients were ambivalent about how they slept in hospital, with high satisfaction (71%) in the presence of significant disruption (63%), preadmission sleep education given to these patients prior to admission potentially contributed to the development of more realistic expectations of the quality of in-hospital sleep.