Traffic air pollution may increase diabetes risk, especially in healthy people

High levels of air pollution from vehicle exhaust may increase the risk of developing type 2 diabetes, especially among healthy people, according to a Reuters Health article about a study published in the journal Diabetes Care.

This is the first study indicating that long-term exposure to air pollution may negatively affect healthier people more than the general population, according to Zorana J. Andersen, lead author of the study and researcher at the Danish Cancer Society.

Data revealed that physically active participants were 10 percent more likely than non-active people to develop diabetes. Non-smokers had a 12 percent higher risk than smokers of developing the disease.

Researchers analyzed data over a ten-year period on almost 52,000 people living in Denmark's two largest cities. They estimated the levels of nitrogen dioxide, a common chemical in vehicle exhaust, at the home addresses of participants dating back to 1971.

The study found that people living in urban areas with high levels of nitrogen dioxide pollution are four percent more likely to be diagnosed with diabetes than people living in areas with less pollutants in the air.

Researchers concluded this after adjusting for traditional risk factors present in patients. The 3,000 participants diagnosed with diabetes were more likely to have traditional diabetes risk factors such as advanced age, overweight or obesity, being male, and a history of current or past smoking.

Women in this study showed a slightly greater risk than men of developing diabetes. While the cause is not yet clear, one possible factor is greater susceptibility to air pollution among females. Another is a higher likelihood of Danish women to spend time in the home.

The study does not prove that air pollution alone causes an increased risk of diabetes, nor does it disprove other possible factors such as poverty and stress. However, the study does indicate that air pollution should be considered among other risk factors for diabetes.

Traditional risk factors are still the greatest indicators of a patient's risk for developing type 2 diabetes. These include older age, obesity, family history of diabetes, history of gestational diabetes, impaired glucose metabolism, physical inactivity and race/ethnicity.

Source: Reuters Health, Centers for Disease Control