The contribution of social isolation and loneliness to sleep disturbances among older adults: a systematic review.

A large number of older people encounter both objective and subjective types of social isolation and sleep disorders. Social isolation increases a person's risk of a wide range of adverse health outcomes and premature death. Social isolation can cause poor sleep quality that has been proposed as one of the possible mechanisms by which social isolation affects people's health and quality of life. The present study was conducted to determine the relationship between objective and subjective social isolation with sleep difficulties among older adults. All articles in PubMed, Web of Science, Scopus, Embase, PsycInfo, and Social care online databases published by December 2020 were systematically searched for relevant published articles. Two authors separately checked the acceptability and quality of the studies using the Newcastle Ottawa checklist. Any disagreement was resolved by consulting the third author. According to the inclusion criteria, 11 studies were systematically reviewed, of which five were cross-sectional, and six were longitudinal studies. No meta-analysis was performed due to the high heterogeneity of the studies. Based on the present study results, both objective and subjective social isolation are related to sleep disturbance in older people. This systematic review showed that objective and subjective social isolation are associated with low sleep quality. It is recommended to investigate the causal relationships and possible pathways that affect the studied variables in future studies.