Cigarettes inflict their worst damage on the lungs of black women, according to a study that compared the lung capacity of different groups of two-pack-a-day smokers and nonsmokers.
And while whites who quit smoking regained some breathing capacity, blacks did not - even 20 years after they quit, said Dr. Henry Glindmeyer, lead author of the study. Both white and black female smokers lost more capacity than did male smokers of either race."This may help explain why chronic obstructive lung disease deaths are increasing for women, but not for men," Glindmeyer said in an interview. "Reduced air flow is an indication of obstruction."
He is presenting a report on the study Sunday at the national joint meeting of the American Lung Association and the American Thoracic Society in New Orleans.
Glindmeyer, a professor at the Tulane University Medical School, said that smoking causes the airways to close slightly. Since women have smaller airways than do most men, he said, they tend to lose more breathing capacity.
The study involved more than 27,000 industrial workers in 15 states. Both smokers and nonsmokers were given tests with a breathing measuring device called a spirometer. The tests measured the amount of air that is exhaled.
A normal value was established for nonsmokers and then compared to the breathing capacity of people age 40 who have smoked two packs of cigarettes daily for 20 years. The study also tested the lung capacity of people who once smoked two packs a day and who had quit for at least 20 years.
On a test of the amount of air exhaled in one second, the study found that black female smokers had 10 percent less capacity than black women who have never smoked. White women had eight percent less than their nonsmoking contemporaries, white men had seven percent less and black men had six percent less.
In the same test comparing former smokers with those who never smoked, black women who once smoked still had 10 percent less capacity than their nonsmoker contemporaries.