September 1, 2009

Pollution linked to elderly heart problems

Exposure to carbon monoxide is associated with an increased risk of hospitalization for the elderly with heart problems, U.S. researchers found.

The nationwide study of 126 urban communities study, published in Circulation: Journal of the American Heart Association, found that an increase in carbon monoxide of 1 part per million in the maximum daily one-hour exposure is associated with a 0.96 percent increase in the risk of hospitalization from cardiovascular disease among people age 65 and older.

However, this link holds true even when carbon monoxide levels are less than 1 part per million -- well below the Environmental Protection Agency's National Ambient Air Quality Standard of 35 parts per million.

Lead investigator Michelle Bell of the Yale School of Forestry & Environmental Studies said the finding suggests an under-recognized health risk to seniors. Currently, the EPA is evaluating the scientific evidence to determine whether the health-based standard should be modified, Bell said.

Bell and colleagues based their findings on an analysis of hospital records for 9.3 million Medicare recipients and data on air pollution levels from 1999-2005.