Active social participation extends the healthy life expectancy of older men without spouses in Japan: The Yamanashi healthy active life expectancy cohort study

This study aimed to evaluate the association between family structure and healthy life expectancy among older Japanese adults, hypothesizing that social participation increases healthy life expectancy more in older men without a spouse than in older women. This study collected data on Healthy Life Expectancy from 541 older adults between 2003 and 2021 from the Healthy Life Expectancy Study, a cohort study of older adults in Yamanashi Prefecture, Japan. The Japanese long-term care insurance system serves as an indicator of a healthy life expectancy. The family structures of participants were categorized as living alone, with a spouse, and with non-spouse cohabitants, whereas social activity frequency was classified as low or high (Community participation was assessed using a 4-point scale: "often," "sometimes," "rarely," and "never."). Cox proportional-hazards regression was used to analyze the relationship between participant characteristics and the loss of healthy life expectancy. Each additional year of age for older men and women increases the risk of loss of healthy life expectancy by 13% and 16%, respectively. The risk of loss of healthy life expectancy was higher among older men who lived alone or lived with non-spouse cohabitants than older living with a spouse (hazard ratio [HR]: 1.95, 95% confidence interval [CI]: 1.01-3.75; hazard ratio: 1.66, 95% confidence interval: 1.05-2.64, respectively). However, older men living without a spouse and engaging in high social activity participation had a lower risk of loss of healthy life expectancy than did those with low social activity participation (hazard ratio: 0.35, 95% confidence interval: 0.17-0.71). In conclusion, older men living without a spouse with high social activity participation had longer healthy life expectancies than those living alone with low social activity participation did.