Air pollution worse for obese people, concludes researcher

Air pollution may be more adverse on the health of obese people, according to a study by Srimathi Kannan, assistant professor of Nutrition, published in the Journal of Epidemiology and Community Health.

The five-year study in Detroit found that residents who lived closest to heavy traffic and other sources of particulate matter pollution had higher pulse pressure, but the impact was greater on those classified as obese, particularly within the first 48 to 96 hours after exposure to pollutants.

High blood pressure increases the risk of heart disease and stroke, and the authors point out that people who are already disadvantaged are being exposed to risk factors that multiply the risks of serious ill health.

The study is gaining notice, with reports appearing during the past week in the Atlanta Journal-Constitution and Modern Medicine.com.

The study, which began in 2000, involved 919 households in three areas of the city that are ethnically and economically diverse and within 5 kilometers of an air quality monitoring site. Kannan and other researchers based their findings on data collected on air quality and biomedical measures for the Health Environments Partnership study.

The researchers noted that particulate matter in the air at one of the study areas was 20 percent higher than the average levels at other locations due to a relatively high concentration of heavy industry, including iron and steel manufacture, coke ovens and refineries.

Just over half of the 348 participants who agreed to give blood samples and have their blood pressure, weight, height and waist circumference measured, were considered obese, according to their body mass index (BMI).

Fifty-seven percent of participants had waist circumferences above the sizes indicative of a higher than average risk for serious ill health, such as diabetes and heart disease. Two thirds of the total sample either had high blood pressure or were on the cusp of a diagnosis of high blood pressure, and 36 percent had high blood cholesterol.

Kannan and the other authors of the study say their findings add to a growing body of work, suggesting that obesity and a midriff bulge boost susceptibility to changes in blood pressure which are associated with ambient air pollution.

Researchers from the University of Michigan, the Detroit Department of Health and Wellness Promotion and the Detroit Hispanic Development Corporation were also involved in the study.

October 20, 2009.

E-mail story to a friendPrinter-friendly version

/more talking points/