Abstract

Research studies connecting air pollution and its effect on health are much needed by the policymakers in India. Generalized additive model (GAM) was applied to quantify the effect of air pollutants on hospital visits related to respiratory diseases for an Indian city, Guwahati. A total of 6335 patients visited the only medical college and hospital in the city for respiratory diseases during 2016-2018. The multi-pollutant GAM models indicate the existence of synergistic effects of particulate matter less than 2.5 µm in diameter (PM_2.5), nitrogen dioxide (NO₂), and carbon monoxide (CO) on hospital visits of the patients due to respiratory diseases. The ambient PM_2.5 concentrations have a strong link with hospital visits in all 6 single lag days. However, the effect of CO on hospital visits due to respiratory diseases was more robust. The percent change of hospital visits associated with each 1 unit increase in CO concentrations at lag 1 day was 15.7% (RR = 1.157; 95% CI 0.929, 1.442), which was enhanced to as high as 40.8% (RR = 1.408; 1.130,1.755) at lag3. The rise of each 10 units of concentrations of PM_2.5 and 1 unit of CO at cumulative lag0-6 day was associated with the percentage change in hospital visits of 6.67% and 62.36% respectively. Single-pollutant GAM models indicate that the risk percentage of PM_2.5 causing respiratory disease increased in combination with other pollutants.

摘要

印度的政策制定者非常需要将空气污染与其对健康的影响联系起来的研究。应用广义加性模型 (GAM) 来量化空气污染物对印度城市古瓦哈提呼吸系统疾病相关医院就诊的影响。2016-2018年，全市唯一的医学院和医院就诊呼吸系统疾病患者共6335人次。多污染物 GAM 模型表明，直径小于 2.5 µm 的颗粒物 (PM _2.5 )、二氧化氮 (NO ₂ ) 和一氧化碳 (CO) 对呼吸系统疾病患者就诊具有协同效应。环境 PM _2.5在所有 6 个单滞后日中，浓度与医院就诊密切相关。然而，一氧化碳对因呼吸系统疾病就诊的影响更为明显。与滞后 1 天 CO 浓度每增加 1 个单位相关的医院就诊百分比变化为 15.7% (RR = 1.157; 95% CI 0.929, 1.442)，增加至高达 40.8% (RR = 1.408; 1.130) ,1.755) 在滞后 3。在累积滞后 0-6 天，每 10 个单位的 PM _2.5浓度和 1 个单位的 CO浓度的上升与住院次数的百分比变化分别相关，分别为 6.67% 和 62.36%。单一污染物 GAM 模型表明 PM _2.5导致呼吸系统疾病的风险百分比与其他污染物一起增加。