Naser, Abdel-Rahman N

INTRODUCTION Gastroesophageal reflux is common in respiratory disease, but the interplay between gastrointestinal mechanisms that expose individuals to reflux and potentially aspiration, and lung mechanics and function remain incompletely understood. Our aim was to investigate this in patients with chronic obstructive pulmonary disease (COPD) and non-idiopathic pulmonary fibrosis (IPF) interstitial lung disease (non-IPF ILD), and compare with our published findings in IPF. METHODS Fifty-seven patients with COPD (aged: 34–75 years) and 64 with non-IPF ILD (22–75 years) who underwent high-resolution impedance manometry and 24-hour pH impedance together with pulmonary function assessment were compared with 35 IPF patients (51–84 years). RESULTS COPD patients were less likely to exhibit ineffective esophageal motility (IEM) and/or absent contractility ( P = 0.009; P = 0.028), and tended to exhibit esophagogastric junction outflow obstruction (EGJOO) and/or hypercontractility ( P = 0.09, P = 0.14) than IPF and non-IPF ILD patients. Notably, integrated relaxation pressure correlated with esophageal length index (ELI) ( P = 0.048) and inspiratory LESP ( P = 0.003), with latter 2 correlating with each other ( P < 0.001). EGJOO patients tended to have fewer proximal reflux events and reduced pulmonary function, with the latter inversely correlating with ELI ( P < 0.05). Non-IPF ILD patients were less likely to exhibit EGJOO than COPD patients ( P = 0.27), and less likely to exhibit IEM ( P = 0.07) than IPF patients. However, those with IEM or EGJOO exhibited greater proportions of reflux events reaching the proximal esophagus than those with normal motility ( P < 0.03), which in contrast to IPF, seemed not to associate with worse pulmonary function. DISCUSSION Associations between esophageal motility, and lung mechanics and function, and consequently reflux, are very disease-specific.

AbstractBackgroundFor many patients with lung disease the only proven intervention to improve survival and quality of life is lung transplantation (LTx). Esophageal dysmotility and gastroesophageal reflux (GER) are common in patients with respiratory disease, and often associate with worse prognosis following LTx. Which, if any patients, should be excluded from LTx based on esophageal concerns remains unclear. Our aim was to understand the effect of LTx on esophageal motility diagnosis and examine how this and the other physiological and mechanical factors relate to GER and clearance of boluses swallowed.MethodsWe prospectively recruited 62 patients with restrictive (RLD) and obstructive (OLD) lung disease (aged 33–75 years; 42 men) who underwent high resolution impedance manometry and 24‐h pH‐impedance before and after LTx.Key ResultsRLD patients with normal motility were more likely to remain normal (p = 0.02), or if having abnormal motility to change to normal (p = 0.07) post‐LTx than OLD patients. Esophageal length (EL) was greater in OLD than RLD patients' pre‐LTx (p < 0.001), reducing only in OLD patients' post‐LTx (p = 0.02). Reduced EL post‐LTx associated with greater contractile reserve (r = 0.735; p = 0.01) and increased likelihood of motility normalization (p = 0.10). Clearance of reflux improved (p = 0.01) and associated with increased mean nocturnal baseline impedance (p < 0.001) in RLD but not OLD. Peristaltic breaks and thoraco‐abdominal pressure gradient impact both esophageal clearance of reflux and boluses swallowed (p < 0.05).Conclusions and InferencesRLD patients are more likely to show improvement in esophageal motility than OLD patients post‐LTx. However, the effect on GER is more difficult to predict and requires other GI, anatomical and pulmonary factors to be taken into consideration.