Endoscopic reflux esophagitis and decline in pulmonary function in nonsmokers: A retrospective cohort study

Background The association between reflux esophagitis and pulmonary function remains controversial. Thus, evaluating the relationship between endoscopic reflux esophagitis and changes in pulmonary function over time in a nonsmoking population is an important clinical issue. Methods In this single-center retrospective cohort study, a medical examination database at Kameda Medical Center Makuhari was employed to identify nonsmokers who underwent upper gastrointestinal endoscopy and spirometry in 2010 and were followed up in 2015. Gastroenterologists carefully double-checked the diagnosis of reflux esophagitis. Multiple linear regression analyses were performed to compare the decline in the percentage of predicted vital capacity (%VC), forced vital capacity (%FVC), and forced expiratory volume in 1 s (%FEV1) between participants with reflux esophagitis and those without. Furthermore, using multivariable logistic regression analyses, we evaluated the factors associated with rapid decline in %VC, %FVC, and %FEV1, which is defined as a decrease of >10% in each parameter over the 5-year observation period. Results We identified 3098 eligible subjects, including 72 and 44 participants who had a Los Angeles classification grade A and B–C (severe) reflux esophagitis in 2010, respectively. The decline in %VC was significantly larger in the participants with severe reflux esophagitis than in the control subjects (standardized coefficient, −0.037; 95% confidence interval, −0.071 to −0.004). Moreover, reflux esophagitis was significantly associated with a rapid decline in %VC and %FVC but not in %FEV1 (P for trend: 0.009, 0.009, and 0.276, respectively). Conclusions Severe reflux esophagitis among nonsmokers had clinical disadvantages in terms of a decline in %VC.