颗粒物长期暴露与抑郁症风险
WHO 2016年年度报告指出，室外空气污染可造成全球每年约300万人的过早死亡。已有研究表明，相较其他大气污染物，颗粒物（PM）对身体健康造成的影响最多，但颗粒物暴露与精神疾病之间的关系尚未得到有力证实。然而，越来越多的研究证据表明了二者之间存在潜在的病因联系。
Braithwaite et al.(2019) 对1974年至2017年关于颗粒物暴露与精神疾病量化关联的相关研究进行了系统性文献综述和荟萃分析，并重点关注了抑郁症风险。图1展示了世界各地研究中PM
2.5长期暴露（>6个月）与抑郁症风险的荟萃分析结果。
图1 世界各地PM2.5长期暴露（>6个月）与抑郁症风险的荟萃分析
在中国地区的有关研究仍相对薄弱。Lin et al.(2017)对PM
2.5长期暴露和抑郁症风险进行了横断面研究，并发现室外PM
2.5污染与抑郁症风险存在显著正比关系。另外，Lin et al.(2016) 和 Gao et al.(2017) 采用交叉研究和时间队列方法，研究了PM
2.5短期暴露与北京和广州地区人口抑郁症风险之间的关系，均发现二者关系显著。值得注意的是，关于空气污染物暴露对人类精神健康影响的研究仍存在挑战（例如精神疾病判定条件不一致、暴露评估不准确和统计学残余混杂问题）。未来需进一步研究来确认两者间潜在的因果关系、降低不确定性。
参考文献：
Braithwaite, I. et al. (2019) ‘Air pollution (Particulate matter) exposure and associations with depression, anxiety, bipolar, psychosis and suicide risk: A systematic review and meta-analysis’, Environmental Health Perspectives. Public Health Services, US Dept of Health and Human Services, 127(12). doi: 10.1289/EHP4595.
Gao Q, Xu Q, Guo X, Fan H, Zhu H. 2017. Particulate matter air pollution associated with hospital admissions for mental disorders: a time-series study in Beijing, China. Eur Psychiatry 44: 68–75, PMID: 28545011, https://doi.org/10.1016/j.eurpsy.2017.02.492.
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整理发布：清洁空气政策伙伴关系（CCAPP）
