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Evaluation of a spatially resolved forest fire smoke model for population-based epidemiologic exposure assessment.

Yao J, Eyamie J, Henderson SB - J Expo Sci Environ Epidemiol (2014)

Bottom Line: Exposure to forest fire smoke (FFS) is associated with multiple adverse health effects, mostly respiratory.We then used meta-regression to estimate the overall effects.Effects on cardiovascular outcomes were only significant using model estimates in all LHAs during extreme fire days.

View Article: PubMed Central - PubMed

Affiliation: Environmental Health Services, British Columbia Centre for Disease Control, Vancouver, British Columbia, Canada.

ABSTRACT
Exposure to forest fire smoke (FFS) is associated with multiple adverse health effects, mostly respiratory. Findings for cardiovascular effects have been inconsistent, possibly related to the limitations of conventional methods to assess FFS exposure. In previous work, we developed an empirical model to estimate smoke-related fine particulate matter (PM2.5) for all populated areas in British Columbia (BC), Canada. Here, we evaluate the utility of our model by comparing epidemiologic associations between modeled and measured PM2.5. For each local health area (LHA), we used Poisson regression to estimate the effects of PM2.5 estimates and measurements on counts of medication dispensations and outpatient physician visits. We then used meta-regression to estimate the overall effects. A 10 μg/m(3) increase in modeled PM2.5 was associated with increased sabutamol dispensations (RR=1.04, 95% CI 1.03-1.06), and physician visits for asthma (1.06, 1.04-1.08), COPD (1.02, 1.00-1.03), lower respiratory infections (1.03, 1.00-1.05), and otitis media (1.05, 1.03-1.07), all comparable to measured PM2.5. Effects on cardiovascular outcomes were only significant using model estimates in all LHAs during extreme fire days. This suggests that the exposure model is a promising tool for increasing the power of epidemiologic studies to detect the health effects of FFS via improved spatial coverage and resolution.

No MeSH data available.


Related in: MedlinePlus

Maps of point estimates for association between a 10 μg/m3 increase in modeled PM2.5 and physician visits for LHAs during extreme fire days. The background color is coded by the values of point estimates and the insets show the major urban areas of Greater Vancouver and Victoria.
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fig5: Maps of point estimates for association between a 10 μg/m3 increase in modeled PM2.5 and physician visits for LHAs during extreme fire days. The background color is coded by the values of point estimates and the insets show the major urban areas of Greater Vancouver and Victoria.

Mentions: Mapping results from the modeled PM2.5 estimates for all 89 LHAs on the most extreme fire days showed spatial overlap between affected areas and large fires for asthma, COPD, and otitis media. The overlap was less consistent for respiratory infections and cardiovascular disease. There were also strong associations for otitis media throughout the urban areas of Greater Vancouver and Victoria that are far removed from fires but still affected by smoke on extreme fire days (Figure 5). For example, Keane33 found that the Greater Vancouver area was affected by FFS in 30% of the summer days during the intense fire season in 2009, with an average PM2.5 increase of 5 μg/m3 on smoke-affected days.


Evaluation of a spatially resolved forest fire smoke model for population-based epidemiologic exposure assessment.

Yao J, Eyamie J, Henderson SB - J Expo Sci Environ Epidemiol (2014)

Maps of point estimates for association between a 10 μg/m3 increase in modeled PM2.5 and physician visits for LHAs during extreme fire days. The background color is coded by the values of point estimates and the insets show the major urban areas of Greater Vancouver and Victoria.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4835685&req=5

fig5: Maps of point estimates for association between a 10 μg/m3 increase in modeled PM2.5 and physician visits for LHAs during extreme fire days. The background color is coded by the values of point estimates and the insets show the major urban areas of Greater Vancouver and Victoria.
Mentions: Mapping results from the modeled PM2.5 estimates for all 89 LHAs on the most extreme fire days showed spatial overlap between affected areas and large fires for asthma, COPD, and otitis media. The overlap was less consistent for respiratory infections and cardiovascular disease. There were also strong associations for otitis media throughout the urban areas of Greater Vancouver and Victoria that are far removed from fires but still affected by smoke on extreme fire days (Figure 5). For example, Keane33 found that the Greater Vancouver area was affected by FFS in 30% of the summer days during the intense fire season in 2009, with an average PM2.5 increase of 5 μg/m3 on smoke-affected days.

Bottom Line: Exposure to forest fire smoke (FFS) is associated with multiple adverse health effects, mostly respiratory.We then used meta-regression to estimate the overall effects.Effects on cardiovascular outcomes were only significant using model estimates in all LHAs during extreme fire days.

View Article: PubMed Central - PubMed

Affiliation: Environmental Health Services, British Columbia Centre for Disease Control, Vancouver, British Columbia, Canada.

ABSTRACT
Exposure to forest fire smoke (FFS) is associated with multiple adverse health effects, mostly respiratory. Findings for cardiovascular effects have been inconsistent, possibly related to the limitations of conventional methods to assess FFS exposure. In previous work, we developed an empirical model to estimate smoke-related fine particulate matter (PM2.5) for all populated areas in British Columbia (BC), Canada. Here, we evaluate the utility of our model by comparing epidemiologic associations between modeled and measured PM2.5. For each local health area (LHA), we used Poisson regression to estimate the effects of PM2.5 estimates and measurements on counts of medication dispensations and outpatient physician visits. We then used meta-regression to estimate the overall effects. A 10 μg/m(3) increase in modeled PM2.5 was associated with increased sabutamol dispensations (RR=1.04, 95% CI 1.03-1.06), and physician visits for asthma (1.06, 1.04-1.08), COPD (1.02, 1.00-1.03), lower respiratory infections (1.03, 1.00-1.05), and otitis media (1.05, 1.03-1.07), all comparable to measured PM2.5. Effects on cardiovascular outcomes were only significant using model estimates in all LHAs during extreme fire days. This suggests that the exposure model is a promising tool for increasing the power of epidemiologic studies to detect the health effects of FFS via improved spatial coverage and resolution.

No MeSH data available.


Related in: MedlinePlus