1. Trajectories of depressive symptom and its association with air pollution: evidence from the Mr. OS and Ms. OS Hong Kong cohort study.
- Author
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Zhao, Yinan, Liu, Qingcai, Chen, Yifei, Kwok, Timothy C. Y., Leung, Jason C. S., Feng, Hui, and Wong, Samuel Yeung Shan
- Subjects
MENTAL depression ,AIR pollution ,GERIATRIC Depression Scale ,COHORT analysis ,AIR pollutants - Abstract
Background: Depression is a global health priority. Maintaining and delaying depressive symptoms in older adults is a key to healthy aging. This study aimed to identify depressive symptom trajectories, predictors and mortality, while also exploring the relationship between air quality and depressive symptoms in older adults in the Hong Kong community over 14 years. Methods: This study is a longitudinal study in Hong Kong. The target population was community-dwelling older adults over age 65. Depressive symptoms were measured by the Geriatric Depression Scale (GDS-15). Group-based trajectory model was used to identify heterogeneity in longitudinal changes over 14 years and examine the associations between baseline variables and trajectories for different cohort members using multinomial logistic regression. The Kaplan–Meier method was employed to conduct survival analysis and explore the variations in survival probabilities over time among different trajectory group. Linear mixed model was used to explore the relationship between air quality and depressive symptoms. Results: A total of 2828 older adults were included. Three different trajectories of depressive symptoms in older people were identified: relatively stable (15.4%), late increase (67.1%) and increase (17.5%). Female, more number of chronic diseases, poor cognitive function, and poor health-related quality of life (HRQOL) were significantly associated with other less favorable trajectories compared with participants with stable levels of depressive symptoms. The late increase group had a lower mortality rate than the relatively stable and increased groups. Lower baseline ambient air pollutant exposure to NO
2 over 14 years was significantly associated with fewer depressive symptoms. Conclusions: In this study, we found that a late increase in depressive symptoms was the predominant trend in older Chinese people in Hong Kong. Poorer HRQOL was predictive of less favorable trajectories of depressive symptoms. Ambient air pollution was associated with depressive symptoms. This novel observation strengthens the epidemiological evidence of longitudinal changes in depressive symptoms and associations with late-life exposure to air pollution. Key points: • This study was intended to capture the trajectories of depressive symptoms and the associated with air quality. • Three different trajectories of depressive symptoms in older people were identified: relatively stable, late increase and increase trajectories. • Female,poor cognitive function, and poorer health-related quality of life were significantly associated with other less favorable trajectories. • After 14 years, the late increase group exhibited a lower mortality rate compared to the relatively stable and increased groups. • Long-term exposure to NO2 over 14 years was significantly associated with more depressive symptoms. [ABSTRACT FROM AUTHOR]- Published
- 2024
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