Objective: To investigate the association between sleep quality and life function in an elderly Japanese population.
Methods: A total of 563 residents of a village in Kumamoto Prefecture aged ≥65 years were asked to fill out a self-administered questionnaire survey from June to July 2010. Sleep quality and life function were respectively evaluated using the Pittsburgh Sleep Quality Index (PSQI) and Basics Check List, which is used to screen elderly individuals at high risk of needing long-term care in the future. As adjustment factors, age, sex, economic situation, residency status, medical history, depression status, and cognitive function were assessed. We examined the relationship between sleep quality and life function using multiple logistic regression analysis, with life function as a dependent variable. Subjects already receiving care or with psychiatric disorders or severe cognitive disturbance were excluded from analysis.
Results: Among the subjects (n=395), a significant relationship was found between poor sleep quality and impaired life function in all models. The odds ratio was 1.82 (95% confidence interval: 1.03-3.23) in the final model controlling for all adjustment factors.
Conclusions: Our findings here suggest a significant relationship between poor sleep quality and impaired life function among elderly community residents. Given these findings, intervention to improve sleep may help delay or prevent the need for long-term care among elderly individuals.