[Predictors of social isolation among older people living in urban area: a prospective study].

Objectives　We aimed to investigate the predictors of social isolation among older people living in urban area.Methods　A mail survey was sent out to 7,015 elderly subjects living in nine districts of Itabashi ward. At baseline (2012), 3,696 subjects and at follow-up (2014) 2,375 replied to the self-administered questionnaire. We defined social isolation as seeing friends or relatives less than two or three times a month. Gender, age, self-rated health, present illnesses, instrumental activities of daily living (IADL), frequency of going out, frequency of social participation, family structure, and perceived financial status were also investigated. A t-test, a chi-square test, and logistic regression analysis were conducted to examine the predictors of social isolation in a follow-up study.Results　Of the 1,791 subjects who were analyzed for social isolation, 348 (19.4%) were found to be socially isolated in 2014. A multiple logistic regression analysis showed that men (adjusted odds ratio, 1.88; 95% confidence interval, 1.41-2.50) were significantly more likely to be isolated than women. Being older (1.03, 1.01-1.06) was also a significant predictor of isolation. Subjects who participated in group activities one to three times a month (1.62, 1.04-2.53) were significantly more likely to be isolated than those who participated in them more than once a week. Subjects who rated their financial status as low (1.67, 1.20-2.32) were more likely to be isolated than those who rated it as high. Subjects who were isolated (10.24, 7.60-13.81), and those who did not respond to questions about isolation (8.15, 3.76-17.67), were significantly more likely to be isolated than those who were not isolated at baseline. Among the subjects who were not isolated at baseline, being male (2.39, 1.57-3.64) and lower self-rated health (3.99, 1.33-11.94) were predictors of social isolation.Conclusion　Participation in social activities is effective in preventing social isolation among elderly men living in urban area.