Background: Studies suggest that increases of fine particle concentrations (PM2.5) could be linked with a rise in cardiovascular disease. With approximately 25% of American adults aged 30 and older reporting having either heart disease or hypertension it is possible that exposure to air pollution could have significant public health consequences. This study examined the relationship between PM2.5 and the prevalence of self-reported hypertension and heart disease using data from a large nation-wide survey.
Study design: Adults, 30 years of age or older, who participated in the National Health Interview Survey (NHIS) from 1999 to 2005 were linked to annual PM2.5 data from the US Environmental Protection Agency (N = 132,224). Annual air quality estimates were averaged from monitors within 20 miles of the respondent's residential block group. Respondents who reported being told they had hypertension by a health professional on two or more separate occasions were defined as hypertensive. Heart disease was defined as answering, "yes" to one or more of three NHIS questions on heart disease.
Results: A 10 microg/m3 increase in PM2.5 exposure was associated with a small elevated risk of hypertension (adjusted odds ratio (OR) 1.05, 95% confidence interval (CI) 1.00-1.10) risk of heart disease (1.08 95% CI 1.00-1.16). The association between PM2.5 and hypertension was found in non-Hispanic white adults (OR 1.10 95% CI 1.04-1.17) but not in non-Hispanic black or Hispanic adults.
Conclusions: Findings from this study complement those from other studies and indicate that PM2.5 adversely affects cardiovascular health. Our results are consistent with other studies in showing a small association between exposure to PM2.5 and cardiovascular outcomes.