The rate of type 2 diabetes and hypertension increases with cumulative levels of exposure to nitrogen oxides, according to a new study led by researchers from the Slone Epidemiology Center (SEC) at Boston University.
Tt is known fact that air pollution increases the risks of acute cardiovascular events such as stroke and myocardial infarction, but now emerging findings from laboratory and clinical studies suggest that air pollution may predispose to both increases the risk of chronic diseases like diabetes and hypertension.
Researchers evaluated the risks associated with exposure to nitrogen oxides (NOx) and particulate matter (PM2.5) in approximately 4,000 African American women living in Los Angeles. NOx are indicators of traffic-related air pollution. From 1995-2005, 531 incident cases of hypertension and 183 incident cases of diabetes occurred among the participants in the Los Angeles area. The risk of diabetes increased by a significant 24 percent, and the risk of hypertension by 11 percent, for each 12 ppb increase in exposure to NOx. There also were suggestive increases in risks of both diseases associated with exposure to (PM2.5), but the evidence for this was weaker than for NOx.
According to the researchers, two previous follow-up studies have suggested that traffic-related pollution increased the incidence of diabetes, but no African Americans were included.