Multiple exposures to airborne pollutants and hospital admissions due to diseases of the circulatory system in Santiago de Chile.
BACKGROUND
High concentrations of various air pollutants have been associated with hospitalization due to development and exacerbation of cardiovascular diseases.


OBJECTIVE
We aimed to assess associations between airborne exposures by particulate matter as well as gaseous air pollutants and hospital admissions due to different cardiovascular disease groups in Santiago de Chile.


METHODS
The study was performed in the metropolitan area of Santiago de Chile during 2004-2007. We applied a time-stratified case-crossover analysis taking temporal variation, meteorological conditions and autocorrelation into account. We computed associations between daily ambient concentrations of carbon monoxide (CO), nitrogen dioxide (NO2), particulate matter (PM10 and PM2.5--particulate matter with aerodynamic diameters less than 10 or 2.5 μm, respectively) or ozone (O3) and hospital admissions for cardiovascular illnesses.


RESULTS
We found for CO, NO2, PM10 and PM2.5 adverse relationships to cardiovascular admissions while effect strength and lag depended on the pollutant and on the disease group. By trend, in 1-pollutant models most adverse pollutants were NO2 and particulate matter (PM10 and PM2.5) followed by CO, while in 2-pollutant models effects of PM10 persisted in most cases whereas other effects weakened. In addition the strongest effects seemed to be immediate or with a delay of up to 2 days. Adverse effects of ozone could not be detected.


CONCLUSIONS
Our results provided evidence for adverse health effects of combined exposure to airborne pollutants. Different pollutants accounted for varying adverse effects within different cardiovascular disease groups. Taking case numbers and effect strength of all cardiovascular diseases into account, mitigation measures should address all pollutants but especially NO2, PM10, and CO.
Core Facility Studies, Helmholtz Centre for Environmental Research-UFZ, Leipzig, Germany. Electronic address: ulrich.franck@ufz.de.
Ulrich
U
Franck
Arne Marian
AM
Leitte
Peter
P
Suppan
D000397:Air Pollution / Q000009:adverse effects / Q000032:analysis*; D002248:Carbon Monoxide / Q000009:adverse effects; D002318:Cardiovascular Diseases / Q000453:epidemiology*; D002677:Chile / Q000453:epidemiology; D002947:Cities; D004781:Environmental Exposure; D006801:Humans; D016015:Logistic Models; D009569:Nitric Oxide / Q000009:adverse effects; D052638:Particulate Matter / Q000009:adverse effects; D010343:Patient Admission / Q000706:statistics & numerical data*
D052638:Particulate Matter; D009569:Nitric Oxide; D002248:Carbon Monoxide
Airborne pollutants; Cardiovascular health effects; Hospital admissions; Multiple exposures