Elsevier

Environment International

Volume 110, January 2018, Pages 139-148
Environment International

Acute effects of ambient air pollution on lower respiratory infections in Hanoi children: An eight-year time series study

https://doi.org/10.1016/j.envint.2017.10.024Get rights and content
Under a Creative Commons license
open access

Highlights

  • Study examined association between ambient air pollution and lower respiratory infection in children.

  • An eight-year time-series study with 57′851 hospital admissions.

  • All markers of ambient air pollution were positively associated with pneumonia related hospitalizations.

  • Associations observed for nitrogen dioxide with pneumonia were independent of those seen for particles.

Abstract

Background

Lower respiratory diseases are the most frequent causes of hospital admission in children worldwide, particularly in developing countries. Daily levels of air pollution are associated with lower respiratory diseases, as documented in many time–series studies. However, investigations in low-and-middle-income countries, such as Vietnam, remain sparse.

Objective

This study investigated the short-term association of ambient air pollution with daily counts of hospital admissions due to pneumonia, bronchitis and asthma among children aged 0–17 in Hanoi, Vietnam. We explored the impact of age, gender and season on these associations.

Methods

Daily ambient air pollution concentrations and hospital admission counts were extracted from electronic databases received from authorities in Hanoi for the years 2007–2014. The associations between outdoor air pollution levels and hospital admissions were estimated for time lags of zero up to seven days using Quasi-Poisson regression models, adjusted for seasonal variations, meteorological variables, holidays, influenza epidemics and day of week.

Results

All ambient air pollutants were positively associated with pneumonia hospitalizations. Significant associations were found for most pollutants except for ozone and sulfur dioxide in children aged 0–17. Increments of an interquartile range (21.9 μg/m3) in the 7-day-average level of NO2 were associated with a 6.1% (95%CI 2.5% to 9.8%) increase in pneumonia hospitalizations. These associations remained stable in two-pollutant models. All pollutants other than CO were positively associated with hospitalizations for bronchitis and asthma. Associations were stronger in infants than in children aged 1–5.

Conclusion

Strong associations between hospital admissions for lower respiratory infections and daily levels of air pollution confirm the need to adopt sustainable clean air policies in Vietnam to protect children's health.

Keywords

Ambient air pollution
Children
Pneumonia
Bronchitis
Asthma
Time-series analysis

Cited by (0)

1

Laura Perez worked at the Swiss Tropical and Public Health Institute until June 2016. Present address of Laura Perez is Holeestrasse 149, 4054 Basel, Switzerland.