The relation between gastroesophageal reflux and pulmonary findings on CT in a general population

<bold>Background:</bold> Nocturnal gastroesophageal reflux (nGER) is common in patients with lung diseases, but the association between GER and structural changes in the lungs is not known. <bold>Aim:</bold> Investigate the association between nGER and pulmonary findings on chest computed tomography (CT) in a general population, with and without risk factors for structural lung changes. <bold>Methods:</bold> Altogether 28,846 general population swedes, aged 50-64 years, answered detailed questionnaires and performed chest CT. Participants with nGER symptoms at least one night per week were defined as with nGER. Chest CT was scored for thickened bronchial walls, bronchiectasis, reticular abnormalities, ground glass opacities, and honey combing. Those who were ever smokers, with current asthma, inflammatory bowel disease or rheumatic disease were defined at risk of having chest CT changes. Analyses were adjusted for sex, age, BMI, education level, and center. <bold>Results:</bold> Among participants with risk factors for CT changes, having nGER associated positively with reticular abnormalities (adj. OR (90% CI): 1.51 (1.04 – 2.17)) and thickened bronchial walls (adj. OR (90% CI): 1.25 (1.07 – 1.48)), but negatively with cysts (adj. OR (90% CI): 0.68 (0.48 – 0.97)). Among participants without risk factors for CT changes, nGER did not associate with CT changes (reticular abnormalities (adj. OR (90% CI): 0.81 (0.42 – 1.57)); thickened bronchial walls (adj. OR (90% CI): 0.88 (0.63 – 1.24))). <bold>Conclusions:</bold> In a middle-aged general population, nGER associates with thickened bronchial walls and reticular abnormalites only among individuals with other risk factors for developing such changes on chest CT, but not among those without risk factors.