Association of Air Pollution with Depressive Symptoms in the Elderly and Effect Modification by Cognitive Performance

摘要

Background: Research regarding the effects of air pollution on depressive symptoms are limited and results are conflicting. Objective: Associations between long-term air pollution exposure and depressive symptoms in the elderly were assessed and whether mild cognitive impairment (MCI) modifies the association of air pollution with depression. Methods: We included 777 elderly women from the SALIA study (age 66-79). Self-reported depressive symptoms were evaluated by the CES-D test score ≥ 16 as a dichotomous outcome. Cognitive performance was assessed by the CERAD-Plus test battery. Air pollutant concentrations were assigned to home addresses by ESCAPE land-use regression models. We also estimated road traffic noise exposure as 24h-mean at facade points. Our adjusted logistic regression models included age, body mass index, smoking habit, environmental tobacco exposure at home, educational level, urban/rural living, physical activity, cardiovascular disease, respiratory diseases, diabetes and the CERAD score as covariates. Results: The prevalence of depressive symptoms and MCI were 15.7% and 59.8%, respectively. In pooled sample, we observed significant associations between an interquartile range (IQR) increase of PM10 (OR= 1.37; 95%CI: 1.07-1.76), PM2.5 (OR= 1.74; 95%CI: 1.20-2.53), N02 (OR= 1.43; 95%CI: 1.04-1.94) and NOx (OR= 1.58; 95%CI: 1.14-2.17) with the presence of depressive symptoms. Women with MCI had more air pollution-induced depressive symptoms: PM10 [OR =1.51 (95% CI: 1.10, 2.07) pint= 0.074], PM2.5 [OR =1.91 (95% CI: 1.20, 3.05) pint=0.073], N02 [OR =1.73 (95% CI: 1.38, 2.64) pint=0.020] and NOx [OR =1.78 (95% CI: 1.17, 2.71) pint=0.009]. We found no associations for women without MCI. No associations were found for coarse fraction of PM, PM2.5 absorbance and noise exposure. Conclusions: Air pollution might affect depressive mood and elderly with MCI might be more prone to develop depression when additionally exposed to air pollution.