Introduction: Gastroesophageal reflux plays a significant role in idiopathic pulmonary fibrosis (IPF).Given the morbidity and mortality associated with IPF, understanding the mechanisms responsible for reflux is essential if patients are to receive optimal treatment and management, especially given the lack of clear benefit of anti-reflux therapies. Our aim was to understand the inter-relationships between esophageal motility, lung mechanics and reflux (particularly proximal reflux -a prerequisite of aspiration), and pulmonary function in IPF patients.
Methods:We prospectively recruited 35 IPF patients (aged 53-75yrs; 27 male) who underwent highresolution impedance manometry and 24-hr pH-impedance, together with pulmonary function assessment.Results: Twenty-two (63%) patients exhibited dysmotility, 16(73%) ineffective esophageal motility (IEM) and 6(27%) esophagogastric junction outflow obstruction. Patients with IEM had more severe pulmonary disease (%FVC:p=0.032) and more proximal reflux (p=0.074) than patients with normal motility. In patients with IEM, intra-thoracic pressure inversely correlated with the number of proximal events (r=-0.429;p=0.098). Surprisingly, inspiratory lower esophageal sphincter pressure (LESP) positively correlated with the percentage of reflux events reaching the proximal esophagus (r=0.583;p=0.018), whilst in patients with normal motility it inversely correlated with the bolus exposure time (r=-0.478;p=0.098) and number of proximal events (r=-0.542;p=0.056). %FVC in IEM patients inversely correlated with the percentage of reflux events reaching the proximal esophagus (r=-0.520;p=0.039) and inspiratory LESP (r=-0.477;p=0.062), and positively correlated with intrathoracic pressure (r=0.633;p=0.008).
Conclusions:We have shown that pulmonary function is worse in patients with IEM which is associated with more proximal reflux events, the latter correlating with lower intra-thoracic pressures and higher LESPs.