Dyadic loneliness and kidney functioning among older couples in Europe

Loneliness is a growing public health concern among the ageing population. Increasingly, scholars have recognised that even married and partnered persons experience loneliness and that loneliness is associated with the health and wellbeing of both partners. Prior research has linked individual loneliness with impaired kidney functioning, but to date no study has explored dyadic associations of both one’s own and a partner’s loneliness with biological measures of kidney function. This study uses dyadic data from the 2015 wave of the Survey of Health, Ageing and Retirement in Europe (SHARE; n = 10,139 individuals from 5,290 couples) to examine associations of both partners’ loneliness with Cystatin C, a blood-based biomarker of kidney function, in a large sample of midlife and older couples in Europe. Multilevel models analysed dyadic data, wherein individuals were nested within couples. Results indicated that both individuals’ own reports of loneliness and their partners’ reports of loneliness were uniquely associated with higher Cystatin C levels. This extends prior research on dyadic loneliness and cardiovascular biomeasures, suggesting Cystatin C may be a physiological pathway for long-term health effects of loneliness – for oneself and a partner. These findings suggest that both being lonely and having a lonely partner may be risk factors for poorer kidney function, which could have implications for the overall health of both partners. We discuss implications of these findings for theory and future research and suggest Cystatin C as a potential biological pathway for harmful effects of dyadic loneliness on health among ageing couples.