More Public Transportation = Less Asthma

From the WebMD Archives

Feb. 20, 2001 -- The extensive public transportation system put in place to prevent traffic meltdown during the 1996 Atlanta Olympic Games also reduced children's asthma attacks by more than 40%, according to a Centers for Disease Control and Prevention (CDC) study reported in this week's Journal of the American Medical Association.

"We found that decreased traffic density during the Olympics was associated with less ozone and other types of pollution, which might be why so many fewer children needed acute medical care for asthma during that period," says lead author Michael S. Friedman, MD, who works in the Air Pollution and Respiratory Health Branch of the CDC's National Center for Environmental Health.

The CDC researchers studied reports of physician visits and hospital care for children aged 1 to 16 years who lived in metropolitan Atlanta during 1996. They compared the number of acute care visits and hospitalizations for asthma during the 17 days of the Olympic Games to those during the four weeks just before and after the Olympics. The researchers also looked at weekday traffic counts.

During the Olympic Games, children with asthma needed 41.6% fewer physician visits and hospitalizations, according to the Georgia Medicaid claims file, and 44.1% fewer, according to a health maintenance organization database. Emergency room visits dropped by over 11%.

These improvements were accompanied by a 27.9% drop in daily peak ozone concentration. The researchers think this was due to a 22.5% decrease in weekday morning traffic.

"There is no question that changes in air quality are one factor in the increased incidence of allergy and asthma in the U.S.," says Andrew Saxon, MD, who was not involved in this study but who has studied the effect of vehicle exhaust on allergy and asthma.

Saxon says he was not surprised to learn that reduced traffic during the Olympics was associated with better health for Atlanta children who have asthma. But he points out that putting these lessons into long-term public policy is a difficult job. Saxon is professor of medicine in the division of clinical immunology and allergy at the University of California in Los Angeles.


"Our study shows that it is possible to change transportation behaviors, at least in the short term, and that if this change continues over a number of days, it can be associated with reduced need for asthma care," Friedman says. "Since 7% of children in the U.S. have asthma, this is an important point."

Atlanta achieved this traffic reduction by putting together an integrated, 24-hour-a-day public transportation system, adding 1,000 buses for park-and-ride services, encouraging local business use of alternative work hours and telecommuting, closing the downtown area to private cars, changing downtown truck delivery schedules, and issuing regular public warnings about traffic and air quality problems.

WebMD Health News Reviewed by Gary D. Vogin, MD
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