Abstract
BACKGROUND: The increasing geriatric population and variation in the disease spectrum among older adults in China contribute to a growing demand for more aged adult care in Chinese society. Relevant studies have shown that living arrangements with various family members have variable impacts on the older adult's health. This study employs the Frailty Index as a unified measurement standard to assess the overall health levels, integrating the specific "in-law relationships" into the research on living arrangements and the health of older adults. METHODS: This study used data from the China Longitudinal Aging Social Survey 2016-2018. OLS and Quantile Regression were used to investigate the in-law relationship on older adult health and whether this impact is homogeneous across older individuals with varying infirmity levels. The study used a lag model and propensity score matching to compensate for potential endogeneity concerns. RESULTS: The study found that residing with a daughter-in-law (20.22%) had a significant positive correlation with the frailty index (β=0.0088, P＜0.001), indicating that the relationship between parents-in-law and daughters-in-law can influence the health of the older adult. This impact is nonlinear and non-homogeneous for older adult people with various levels of frailty, exhibiting an approximately decreasing and then increasing U-shaped distribution, which denotes that older adult people with different health conditions have distinct demands for intergenerational care. In addition, this impact varies among older adult groups of disparate genders, urban and rural areas, and age groups. CONCLUSION: This study investigates the impact of "in-law relationships" within living arrangements on the health of older adults. It shows that co-residing with a daughter-in-law has adverse effects on the health of older adults. Therefore, the study suggests that when the health and economic conditions of the elderly permit, a "live-near-but-not-with" living arrangement with their children can be considered.