Effect modification of kitchen ventilation on the associations of solid fuel use and long-duration cooking with the increased prevalence of depressive and anxiety symptoms: The Henan Rural Cohort Study

Although solid fuel use for cooking is linked to an increased risk for depression, there is limited evidence on the effects of cooking duration and kitchen ventilation on these associations in rural areas. Among 29 903 participants from the Henan Rural Cohort, the independent and combined associations of cooking fuel type, cooking duration, and kitchen ventilation with depressive and anxiety symptoms were examined by logistic regression models and restricted cubic spline. The adjusted odds ratios (aORs) and 95% confidence intervals (CIs) of solid fuel use for depressive and anxiety symptoms were 1.237 (1.041, 1.469) and 1.384 (1.153, 1.662), respectively. Increased cooking duration was associated with an increased prevalence of depressive symptoms (aOR: 1.098, 95% CI: 1.033, 1.166) and anxiety symptoms (aOR: 1.074, 95% CI: 1.009, 1.144). Solid fuel use and long-duration cooking associated with increased prevalence of depressive and anxiety symptoms were only observed in individuals without kitchen ventilation. Kitchen ventilation may attenuate the positive associations of solid fuel use and long-duration cooking with the prevalence of depressive and anxiety symptoms, which suggested popularizing clean fuel and promoting kitchen ventilation may be effective strategies to improve mental health related to household air pollution sourced from solid fuel use and long-duration cooking.