Short-term exposure to air pollution and hospital admission for pneumonia: a systematic review and meta-analysis

Abstract

Background Air pollution is a major issue that poses a health threat worldwide. Although several studies investigated the adverse effects of air pollution on various diseases, few have directly demonstrated the effects on pneumonia. Therefore, we performed a systematic review and meta-analysis on the associations between short-term exposure of air pollutants and hospital admission or emergency room (ER) visit for pneumonia. Methods A literature search was performed using PubMed, Embase, and Web of Science up to April 10, 2020. Pooled estimates were calculated as % increase with 95% confidence intervals using a random-effects model. A sensitivity analysis using the leave-one-out method and subgroup analysis by region were performed. Results A total of 21 studies were included in the analysis. Every 10 μg/m3 increment in PM2.5 and PM10 resulted in a 1.0% (95% CI: 0.5–1.5) and 0.4% (95% CI: 0.2–0.6) increase in hospital admission or ER visit for pneumonia, respectively. Every 1 ppm increase of CO and 10 ppb increase of NO2, SO2, and O3 was associated with 4.2% (95% CI: 0.6–7.9), 3.2% (95% CI: 1.3–5.1), 2.4% (95% CI: − 2.0-7.1), and 0.4% (95% CI: 0–0.8) increase in pneumonia-specific hospital admission or ER visit, respectively. Except for CO, the sensitivity analyses yielded similar results, demonstrating the robustness of the results. In a subgroup analysis by region, PM2.5 increased hospital admission or ER visit for pneumonia in East Asia but not in North America. Conclusion By combining the inconsistent findings of several studies, this study revealed the associations between short-term exposure of air pollutants and pneumonia-specific hospital admission or ER visit, especially for PM and NO2. Based on the results, stricter intervention policies regarding air pollution and programs for protecting human respiratory health should be implemented.

Ambient Particulate Air Pollution and Daily Hospital Admissions in 31 Cities in Poland

“…Dominici et al (2006) [13] report PM 2.5 -related RR for hospital admissions due to COPD at the level of 1.0091 (95% CI, from 1.0018 to 1.0164), while, in the review by DeVries et al (2016) [36], the RR of COPD hospitalization ranged from 1.014 to 1.025 per 10 µg/m 3 of PM 2.5 . The RR value obtained in a worldwide meta-analysis [34] for admissions due to pneumonia (all ages) equaled 1.010 (95% CI, from 1.005 to 1.015). In the study of Liu et al (2019) [15], RS mortality due to PM 2.5 exposure was associated with RR = 1.0074 (95% CI, from 1.0053 to 1.0095).…”

“…The WHO HRAPIE report [33] indicates PM 10 -related RR only for the incidence of asthma symptoms in asthmatic children aged 5-19 years, and this is 1.028 (95% CI, from 1.006 to 1.051). A recent meta-analysis by Yee et al (2021) [34] for hospitalization due to pneumonia reports RR at the level of 1.004 (95% CI, from 1.002 to 1.006) per 10 µg/m 3 of PM 10 . RS mortality due to PM 10 exposure was associated with RR = 1.0047 (95% CI, from 1.0035 to 1.0058) in the study of Liu et al (2019) [15].…”

Air pollution and hospital admissions for critical illness in emergency department: a tertiary-center research in Changsha, China, 2016–2020

“…Chronic obstructive pulmonary disease (COPD) exacerbations were also related to poor air quality (Boehm et al 2021). A metaanalysis including 21 studies showed that with every 10 μg/ m 3 increment in PM 2.5 and PM 10 , the increase in ED admissions for pneumonia were 1.0% (95% CI 0.5-1.5) and 0.4% (95% CI 0.2-0.6), respectively (Yee et al 2021).…”

Ventilation-Associated Particulate Matter Is a Potential Reservoir of Multidrug-Resistant Organisms in Health Facilities

“…The indicated risk, however, can be controlled through enhanced environmental cleaning and disinfection procedures [ 27 ]. Currently, hospital air quality is recognised as an important determinant in preventing airborne transmission of HCAIs [ 28 ] and ambient air pollution is a well-established risk factor of community-acquired pneumonia in both adults [ 29 , 30 ] and children [ 31 , 32 , 33 ]. The distributions and compositions of air streams as well as their microbial contamination are determined by the amount and velocity of natural ventilation [ 28 , 34 , 35 ]; implementation of sophisticated mechanical ventilation systems [ 28 , 35 ]; differential regulation of air pressure [ 35 ]; efficiency of air filtration [ 35 ]; indoor air temperature [ 35 ]; and relative humidity [ 35 ].…”

“…Different-sized PM fractions have distinct penetration depths: Coarse PM (PM 10 or PM 2.5–10 having aerodynamic diameter between 2.5 and 10 µm) are retained in the upper airways, while fine PM (PM 2.5 or PM 0.1–2.5 having aerodynamic diameter between 0.1 and 2.5 µm) reaches the alveoli, and ultrafine PM (PM 0,1 having aerodynamic diameter ≤0.1 µm) might trespass the blood–air barrier and enter the circulation [ 42 ]. Accordingly, PM 0.1–2.5 is predominant in the lungs and is mainly responsible for pneumonia [ 29 , 30 ] and chronic obstructive pulmonary disease [ 43 , 44 , 45 ], while PM 2.5–10 is primarily associated with upper respiratory tract infections [ 46 , 47 ]. Despite the well-defined role of PM in respiratory diseases, the role of hospital PM as a vehicle for bacterial and viral agents causing HCAIs has been largely neglected to date, albeit the critical reviews suggested the potential importance of ventilation system contamination in the spread of HCAIs [ 48 , 49 ].…”