UAB Media Relations

Chronic obstructive pulmonary disease (COPD) is under-diagnosed in smokers and former smokers at risk for lung cancer, say researchers with the UAB Lung Health Center.

COPD, the fourth leading cause of death in the United States, is dramatically more prevalent in this at-risk population than has been previously believed, according to findings being presented at the American College of Chest Physicians meeting in Salt Lake City Oct. 25.

“Traditional teaching has always been that COPD is found in 15-20 percent of smokers or former smokers,” said Chad E. Miller, M.D., a fellow in UAB’s Division of Pulmonary, Allergy and Critical Care Medicine and principal investigator of the study. “However, our analysis indicates that number is much higher. Our findings suggest that more than half of smokers or former smokers may have COPD.”

Miller and colleagues studied patients enrolled in the National Lung Screening Trial, which compared chest X-rays versus CT scans for early detection of lung cancer. Miller’s team obtained medical information and performed spirometry on 449 trial participants. The spirometry test, a measure of lung function, showed that more than half, or 53 percent, had airflow limitation compatible with a diagnosis of COPD. Only 80 of those 236 individuals had a prior diagnosis of COPD, while only 42, or just 18 percent, had received treatment for the condition.

“These findings clearly indicate that COPD is under-recognized and under-treated in patients at risk for lung cancer,” said Mark T. Dransfield, M.D., assistant professor of pulmonary, allergy and clinical care medicine at UAB and a study co-author.

“Physicians should be more alert to the possible presence of COPD in smokers and former smokers,” Dransfield said. COPD is a slowly progressive disease of the airways that is characterized by a gradual loss of lung function. COPD includes chronic bronchitis, chronic obstructive bronchitis, emphysema or a combination of these conditions.

The symptoms of COPD can range from chronic cough and sputum production to severely disabling shortness of breath. In some individuals, chronic cough and sputum production are the first signs that they are at risk for developing the airflow obstruction and shortness of breath characteristic of COPD. In others, shortness of breath may be the first indication of the disease.

In America, the most important risk factor for COPD, by far, is cigarette smoking. The most important measure for preventing COPD - and for slowing disease progression - is avoidance of smoking.