Epidemiol Psychiatr Sci. 2025 Nov 13;34:e55. doi: 10.1017/S2045796025100292.
ABSTRACT
AIMS: Fine particulate matter (PM2.5) exposure and unfavourable lifestyle are both significant risk factors for mental health disorders, yet their combined effects on adolescent depression and anxiety remain poorly understood. This study aims to determine whether PM2.5 exposure and lifestyle are independently associated with adolescent depression and anxiety, and whether there are joint effects between these factors on mental health outcomes.
METHODS: In this cross-sectional study, 19852 participants were analysed. PM2.5 concentrations were obtained from the ChinaHighAirPollutants (CHAP) dataset. Lifestyle factors were assessed through self-reported questionnaires, and a healthy lifestyle score was developed based on eight lifestyle risk factors. Depression and anxiety were assessed using the PHQ-9 and GAD-7 scales. Restricted cubic spline analysed dose-response relationships between PM2.5 exposure and mental health outcomes. The independent and joint effects were assessed using logistic regression models. Both multiplicative and additive interactions (relative excess risk due to interaction, RERI) were examined. Multiple classification approaches were incorporated to ensure robust results.
RESULTS: The study included 19852 participants with a mean age of 15.16 years (SD 1.60), comprising 9886 (49.8%) males and 9966 (50.2%) females. Depression and anxiety were identified in 3845 (19.37%) and 3230 (16.27%) participants, respectively. PM2.5 exposure showed a linear dose-response relationship with depression and anxiety. Joint effects analysis at the 75th percentile of PM2.5 with a lifestyle risk score of 4 revealed the strongest associations, with adjusted odds ratios of 4.49 (95% CI: 3.79-5.33) for depression, 4.01 (95% CI: 3.36-4.78) for anxiety and 4.24 (95% CI: 3.52-5.10) for their comorbidity. Simultaneously, significant additive interactions (RERI > 0) between high levels of PM2.5 exposure and unfavourable lifestyle factors were detected, suggesting synergistic effects on mental health outcomes. Subgroup and sensitivity analyses confirmed the robustness of these findings.
CONCLUSIONS: High PM2.5 exposure and unfavourable lifestyle factors demonstrated significant independent and joint effects on depression and anxiety among adolescents. These findings highlight that implementing stringent air pollution control measures, combined with promoting healthy lifestyle practices, may be crucial for protecting adolescent mental health.
PMID:41229182 | DOI:10.1017/S2045796025100292
