Impact of gastroesophageal reflux on longitudinal lung function and quantitative computed tomography in the COPDGene cohort

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.

Potential systemic effects of acquired CFTR dysfunction in COPD

Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation, respiratory symptoms, inflammation of the airways, and systemic manifestations of the disease. Genetic susceptibility and environmental factors are important in the development of the disease, particularly exposure to cigarette smoke which is the most notable risk factor. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene are the cause of cystic fibrosis (CF), which shares several pathophysiological pulmonary features with COPD, including airway obstruction, chronic airway inflammation and bacterial colonization; in addition, both diseases also present systemic defects leading to comorbidities such as pancreatic, gastrointestinal, and bone-related diseases. In patients with COPD, systemic CFTR dysfunction can be acquired by cigarette smoking, inflammation, and infection. This dysfunction is, on average, about half of that found in CF. Herein we review the literature focusing on acquired CFTR dysfunction and the potential role in the pathogenesis of comorbidities associated with COPD and chronic bronchitis.

The Impact of Erosive Reflux Esophagitis on the Decline of Lung Function in the General Population

BACKGROUND

The impact of reflux esophagitis on the decline of lung function has been rarely reported. This study was performed to evaluate the association between erosive reflux esophagitis and lung function changes.

METHODS

We included patients with normal lung function who underwent esophagogastroduodenoscopy for health screening from a health screening center. Patients with persistent erosive reflux esophagitis on two discrete endoscopic examinations were designated as the erosive reflux esophagitis group. We also selected patients without erosive reflux esophagitis and matched them 1:4 with patients from the erosive reflux esophagitis group. We estimated annual forced expiratory volume in 1 second (FEV₁) and forced vital capacity (FVC) changes from baseline and compared these estimates by the linear mixed regression model. We also estimated the biannual incidence of chronic obstructive pulmonary disease (COPD).

RESULTS

In total, 1,050 patients (210 patients with erosive reflux esophagitis, and 840 matched controls) were included. The median follow-up duration for spirometry was six years. In patients with erosive reflux esophagitis, mild reflux esophagitis (A grade) was most common (165 patients, 78.6%). The adjusted annual FEV₁ change in patients with erosive reflux esophagitis was -51.8 mL/yr, while it decreased by 46.8 mL/yr in controls (P = 0.270). The adjusted annual FVC decline was similar between the two groups (-55.8 vs. -50.5 mL/yr, P = 0.215). The estimated COPD incidence during the follow-up period was not different between the erosive reflux esophagitis and control groups.

CONCLUSION

In patients with normal lung function, the presence of erosive reflux esophagitis did not affect the annual declines in FEV₁ or FVC.

Focus on gastroesophageal reflux disease in patients with cystic fibrosis

Gastroesophageal reflux disease (GERD) is a common gastrointestinal disorder in cystic fibrosis (CF), and based on various studies, its prevalence is elevated since childhood. There are several pathogenetic mechanisms on the basis of association between CF and GERD. However, there are no specific guidelines for GERD in CF patients, so diagnosis is based on guidelines performed on patients not affected by CF. The aim of this review is to provide the pathophysiology, diagnostic and therapeutic options, complications, and future directions in the management of GERD patients with CF.