NEW YORK (Reuters Health) — More than half of patients with advanced COPD have gastroesophageal reflux disease (GERD), new research suggests.In GERD, stomach acid seeps into the esophagus causing burning and pain in the chest. COPD, short for chronic obstructive pulmonary disease, is a progressive lung disease caused by smoking that includes emphysema and chronic bronchitis.

Dr. R. Kempainen and colleagues at the University of Minnesota School of Medicine, Minneapolis looked for signs of GERD using standard tests in 42 adults with advanced COPD.

The overall prevalence of GERD was 57 percent, even though only 26 percent of affected patients reported heartburn or acid regurgitation during the study.

“The study confirms a high prevalence of GERD among patients with severe COPD, often in the absence of reflux symptoms,” Kempainen told Reuters Health.