Background

Studies have observed associations between long-term air pollution and cardiovascular disease hospitalization. Little is known, however, about effect modification of these associations by greenness, temperature and humidity.

Methods

We constructed an open cohort consisting of all fee-for-service Medicare beneficiaries, aged ≥ 65, living in the contiguous US from 2000 through 2016 (~63 million individuals). We assigned annual average PM_2.5, NO₂ and ozone zip code concentrations. Cox-equivalent Poisson models were used to estimate associations with first cardiovascular disease (CVD), coronary heart disease (CHD) and cerebrovascular disease (CBV) hospitalization.

Results

PM_2.5 and NO₂ were both positively associated with CVD, CHD and CBV hospitalization, after adjustment for potential confounders. Associations were substantially stronger at the lower end of the exposure distributions. For CVD hospitalization, the hazard ratio (HR) of PM_2.5 was 1.041 (1.038, 1.045) per IQR increase (4.0 µg/m³) in the full study population and 1.327 (1.305, 1.350) per IQR increase for a subgroup with annual exposures always below 10 µg/m³ PM_2.5. Ozone was only positively associated with CVD, CHD and CBV hospitalization for the low-exposure subgroup (<40 ppb). Associations of PM_2.5 were stronger in areas with higher greenness, lower ozone and O_x, lower summer and winter temperature and lower summer and winter specific humidity.

Conclusion

PM_2.5 and NO₂ were positively associated with CVD, CHD and CBV hospitalization. Associations were more pronounced at low exposure levels. Associations of PM_2.5 were stronger with higher greenness, lower ozone and O_x, lower temperature and lower specific humidity.

中文翻译：

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空气污染和心血管疾病住院治疗——关联性是否会因绿色、温度和湿度而改变？

 背景

研究观察到长期空气污染与心血管疾病住院之间存在关联。然而，人们对绿色、温度和湿度对这些关联的影响知之甚少。

 方法

我们构建了一个开放队列，其中包括 2000 年至 2016 年间居住在美国本土、年龄≥65 岁的所有按服务付费医疗保险受益人（约 6300 万人）。我们指定了年平均 PM _2.5 、NO ₂和臭氧邮政编码浓度。使用 Cox 等效泊松模型来估计与首次心血管疾病 (CVD)、冠心病 (CHD) 和脑血管疾病 (CBV) 住院治疗的关联。

 结果

调整潜在混杂因素后，PM _2.5和 NO ₂均与 CVD、CHD 和 CBV 住院呈正相关。在暴露分布的低端，关联性明显更强。对于 CVD 住院，在整个研究人群中，PM _2.5每增加 IQR (4.0 µg/m ³ )，PM 2.5 的风险比 (HR) 为 1.041 (1.038, 1.045)，而在每年 IQR 增加的亚组中，PM 2.5 的风险比 (HR) 每增加 1.327 (1.305, 1.350)。暴露量始终低于 10 µg/m ³ PM _2.5 。对于低暴露亚组，臭氧仅与 CVD、CHD 和 CBV 住院呈正相关（<40 id=12>2.5 在绿化较高、臭氧和 O _x较低、夏季和冬季温度较低以及夏季和冬季较低的地区更强）特定湿度。

 结论

PM _2.5和NO ₂与CVD、CHD 和CBV 住院呈正相关。在低暴露水平下关联更为明显。 PM _2.5与较高绿度、较低臭氧和 O _x 、较低温度和较低比湿度的关联性更强。