Sex differences in the relationship between household solid fuel use and incident stroke and the mediating role of depressive symptoms in middle-aged and older Chinese adults

Household solid fuel use is associated with a higher risk of a wide spectrum of health disorders. However, the sex-specific relationship between solid fuel use and incident stroke in older Chinese adults, as well as the potential mediating role of depressive symptoms, remains insufficiently explored. This longitudinal study used data from the China Health and Retirement Longitudinal Study (CHARLS), including 13,928 Chinese participants aged 45 years or older who were free of stroke at baseline. Logistic regression models were used to assess the relationship between solid fuel use, depressive symptoms, and the risk of incident stroke. Mediation analyses were performed to quantify the potential mediation role of depressive symptoms in the association. All analyses were stratified by sex to assess sex-specific susceptibility. Of the 13,928 adults (mean age of 58, 47.26% male), 917 (6.58%) participants documented the incident stroke. Solid fuel use was significantly associated with a higher risk of incident stroke in the total population (OR = 1.26, 95% CI: 1.06–1.49) and female populations (OR = 1.39, 95% 1.09–1.77) in the fully adjusted model. In addition, depressive symptoms may partially mediate up to15.7% of the association between solid fuel use and incident stroke, and this finding was consistent whether depressive symptoms were defined as general depression or severe depression. The results of the stratified analysis also indicate that this mediating effect is present only among the female group. Household solid fuel use was significantly associated with a higher risk of incident stroke, and depressive symptoms played a mediating role in the relationship. These findings highlight the need for integrated public health interventions in the areas of environmental pollution and mental health, with particular attention to women.