Factors associated with short and long sleep duration in older adults: Analysis of a national survey in Japan.

Aim: This study aimed to clarify the association between sleep duration and various physical and psychosocial factors among older Japanese adults.

Methods: Data from 295 367 households were obtained from the 2013 Comprehensive Survey of Living Conditions in Japan, a self-administered questionnaire survey. We restricted our analyses to 115 205 participants who responded to all the items required for this study. Multinomial logistic regression models examined the association between sleep duration and various factors.

Results: Overall, 26.0% of the participants slept for <6 h, 56.0% slept for 6-8 h, and 18.0% slept for ≥8 h. Poor subjective health and mental health increased the risk of both short (poor subjective health: odds ratio [OR] 1.22, 95% confidence interval [CI] 1.17-1.27; severe mental distress: OR 2.21, 95% CI 2.04-2.40) and long (poor subjective health: OR 1.19, 95% CI 1.13-1.24; severe mental distress: OR 1.25, 95% CI 1.13-1.38) sleep duration. Many subjective symptoms, including chest, respiratory, musculoskeletal and urogenital symptoms, were associated with short sleep duration. However, only memory loss was associated with long sleep duration (OR 1.23, 95% CI 1.16-1.31).

Conclusions: We need to be aware that older people with short sleep duration may have various physical symptoms. Moreover, as physical and mental problems, cognitive decline and unhealthy lifestyles are associated with long sleep duration, we also need to pay attention to the living conditions of those who complain of long sleep duration. The limitations of this study were that the variables were self-reported and sleep duration was not evaluated objectively. Geriatr Gerontol Int 2022; 22: 660-666.