Effects of gastroesophageal reflux disease treatment with proton pump inhibitors on the risk of acute exacerbation and pneumonia in patients with COPD

BACKGROUND: Gastroesophageal reflux disease (GERD) has been suggested as a risk factor for acute exacerbation of chronic obstructive pulmonary disease (COPD). However, it remains undetermined whether proton pump inhibitor (PPI) treatment reduces the risk of exacerbation or affects the risk of pneumonia. This study aimed to evaluate the risks of both exacerbation and pneumonia following PPI treatment for GERD in patients with COPD. METHODS: This study used a reimbursement database of the Republic of Korea. Patients aged ≥ 40 years with COPD as a main diagnosis and who received PPI treatment for GERD at least for 14 consecutive days between January 2013 and December 2018 were included in the study. A self-controlled case series analysis was conducted to calculate the risk of moderate and severe exacerbation and pneumonia. RESULTS: A total of 104,439 patients with prevalent COPD received PPI treatment for GERD. The risk of moderate exacerbation was significantly lower during the PPI treatment than at baseline. The risk of severe exacerbation increased during the PPI treatment but significantly decreased in the post-treatment period. Pneumonia risk was not significantly increased during the PPI treatment. The results were similar in patients with incident COPD. CONCLUSIONS: The risk of exacerbation was significantly reduced after PPI treatment compared with the non-treated period. Severe exacerbation may increase due to uncontrolled GERD but subsequently decrease following PPI treatment. There was no evidence of an increased risk of pneumonia. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12931-023-02345-1.