Kempainen RR, Savik K, Whelan TP, et al. High prevalence of proximal and distal gastroesophageal reflux disease in advanced COPD. Chest. 2007 Jun; 131(6):1666-1671.

Little is known about gastroesophageal reflux disease (GERD) in patients with chronic obstructive pulmonary disease (COPD); however, GERD is common in many other chronic respiratory diseases. This study evaluated the prevalence, presentation, and predictors of GERD based on proximal and distal esophageal pH monitoring in patients with severe COPD. The overall prevalence of GERD was 57%, but only one-third reported heartburn or acid regurgitation during the study. Only higher body mass index was predictive of reflux on regression analysis. The authors concluded that while GERD is common in patients with COPD, most are asymptomatic and have a relatively high prevalence of isolated abnormal proximal reflux.