Sex differences in the relationship of intraindividual difference in estimated glomerular filtration rate by cystatin C and creatinine and depressive symptoms among middle-aged and older adults in China.

Background: The estimated glomerular filtration rate based on cystatin C (eGFRcys) and creatinine (eGFRcr) may differ substantially within an individual. The clinical implications of these differences (eGFRdiff) for depressive symptoms risk are unknown and whether it differed by sex are also unknown.

Methods: The prospective cohort study enrolled 3443 participants aged ≥45 years from the 2011-2020 waves of the China Health and Retirement Longitudinal Study. The eGFRdiff was calculated by eGFRcys minus eGFRcr at baseline. Depressive symptoms were measured by the ten-item Center for Epidemiologic Studies Depression Scale. Unadjusted and adjust logistic regression models were used to investigate the relationship between eGFRdiff and depressive symptoms.

Results: 1628 (47.3 %) females and 1815 (52.7 %) males were analyzed in the present study. When considering eGFRdiff as a continuous variable, multivariate logistic regression analysis showed that higher eGFRdiff was associated with reduced depressive symptoms in females (OR = 0.985, 95%CI 0.976-0.995, p-value = 0.020), not in males (OR = 0.996, 95%CI 0.988-1.003, p-value = 0.280). The associations remained similar when comparing individuals across different eGFRdiff categories.

Conclusions: In this 9-year follow-up cohort study, baseline eGFRdiff was negatively associated with depressive symptoms among community-dwelling middle-aged and older females, but not males. Monitoring eGFRdiff could have clinical utility in identifying the risk of accelerated depressive symptoms progression in females.