FRIDAY, April 25, 2014 (HealthDay News) -- People who have chronic obstructive pulmonary disease, or COPD, are less likely to be hospitalized for breathing problems if they live in an area where local laws prohibit smoking in public spaces including bars, restaurants and offices, a new study shows.
"Kentuckians with COPD that live in a community with strong smoke-free laws were 22 percent less likely to be put in the hospital compared to those who were in a community with no law or a weak law," said study author Ellen Hahn, director of the Tobacco Policy Research Program at the University of Kentucky's College of Nursing in Lexington.
COPD is a progressive lung disease characterized by chronic inflammation of the airways. People who have COPD often feel short of breath, or they may cough or wheeze. Medication can help control the symptoms, but there's no cure. It's currently the third leading cause of death in the United States, according to the U.S. Centers for Disease Control and Prevention.
Irritants such as pollen, air pollution and cigarette smoke can cause COPD to suddenly get worse. These flare-ups require immediate medical attention. A particularly bad episode may require a stay in the hospital to help stabilize breathing.
Most hospital stays for COPD are for acute flare-ups, according to a 2011 statistical brief published by the U.S. Agency for Healthcare Research and Quality. These stays averaged about five days each and cost around $7,500.
For the current study, researchers in Kentucky -- a state that has nearly double the average rate of COPD worldwide -- mined a statewide database to find all the hospitalizations for COPD there from 2003 through 2011. They found nearly 150,000 COPD hospitalizations during the eight-year study period.
The investigators then compared rates of hospitalizations in 16 counties with strong smoke-free laws to hospitalization rates in the remaining 104 Kentucky counties, with weak or no laws against smoking in public spaces.
The researchers also accounted for other factors that might influence hospitalizations, such as whether the county was primarily urban or rural, how many doctors were available in the area, and rates of diseases that can co-occur with COPD, like diabetes and heart disease.
After ruling all that out, the study authors still found a pretty dramatic difference. People living in counties with comprehensive smoke-free laws or regulations were 22 percent less likely to be hospitalized for COPD compared to those in counties with fewer smoking restrictions, according to the study.
Time also seemed to play a role. There was a steep decline in hospitalizations in areas where tough laws had been in place for at least a year, she said, but little difference in areas with newer laws.
"It kind of takes a while for a law to be in place to see an effect on respiratory health," Hahn said.
Experts who were not involved in the research praised the study for sorting out a question that's been tricky to answer -- whether smoke-free laws make a difference for patients with COPD.
"We know that prohibiting smoking in public places has a dramatic effect on heart attacks, and that's been shown over and over again. The number varies anywhere from 10 to 20 percent," said Dr. Norman Edelman, a senior medical advisor for the American Lung Association.
"But the issue with COPD has been harder. Some studies have shown an effect, some haven't," Edelman said.
Because this study is one of the largest so far to try to answer the question, it really helps to show the value of laws that ban smoking in public places, according to Edelman.
"Since COPD is such a prevalent disease and it costs so much in terms of care and hospitalization, this is a potentially important finding," he added.
The study was published online April 17 in the American Journal of Public Health.
For more about COPD, visit the U.S. National Heart, Lung, and Blood Institute.