Air pollution and symptoms of depression in elderly adults

Although the effect of air pollution on various diseases has been extensively investigated, few studies have examined its effect on depression. During the present study, the authors investigated the effect of air pollution on symptoms of depression in an elderly population. Five hundred and thirty-seven participants were enrolled in the study who regularly visited a community centre for the elderly located in Seoul, Korea. The Korean version of the Geriatric Depression Scale-Short Form (SGDS-K) was used to evaluate depressive symptomatology during a 3-yr follow-up study. The authors associated ambient air pollutants with SGDS-K results using generalised estimating equations (GEE). In addition, they conducted a factor analysis with items on the SGDS-K to determine which symptoms were associated with air pollution. SGDS-K scores were positively associated with interquartile range (IQR) increases in the 3-day moving average concentration of particulate matter with an aerodynamic diameter e 10 ím (PM10) [17.0% increase in SGDS-K score, 95% confidence interval (CI): 4.9%, 30.5%], the 0-7 day moving average of nitrogen dioxide [NO2; 32.8% (95% CI: 12.6%, 56.6%)], and the 3-day moving average of ozone [O3; 43.7% (95% CI: 11.5%, 85.2%)]. For these three pollutants, factor analysis showed that air pollution was more strongly associated with emotional symptoms such as feeling happy and satisfied than with somatic or affective symptoms. The authors concluded that the findings suggest that increases in PM10, NO2, and O3 may increase depressive symptoms among the elderly. Of the symptoms evaluated, ambient air pollution was most strongly associated with emotional symptoms.