Relationship between interstitial lung disease and oesophageal dilatation on chest high-resolution computed tomography in patients with systemic sclerosis: a cross-sectional study

Oesophageal dilatation (OD) has been implicated in the pathogenesis of interstitial lung disease (ILD) in systemic sclerosis (SSc). The aims of this study were to explore the association of the OD and SSc-ILD on chest high-resolution computed tomography (HRCT), and to establish a cutoff point for the OD suggestive for the presence of a significant lung involvement. The widest oesophageal diameter (WOD) was obtained on axial HRCT images. The parenchymal abnormalities on HRCT were coded and scored according to Warrick method. Patient-centred measures, pulmonary function tests and the single breath carbon monoxide diffusing capacity of the lung (DLco) were also obtained. Multivariate regression analysis was performed to identify factors associated with oesophageal diameter. 126 subjects with SSc were included. The mean (+/- SD) WOD was 13.5 (+/- 4.2) mm, and in 76 (60.3%) participants WOD was >= 11 mm. SSc patients with ILD had larger oesophageal diameters than those without lung disease (19.4 vs. 14.1 mm, p < 0.001). We observed a high correlation between WOD and gastro-oesophageal reflux disease questionnaire (GerdQ) (r = 0.886, p < 0.001), Borg score (r = 0.705, p < 0.001), and Warrick score (r = 0.614, p < 0.001). WOD negatively correlated with DLco (r = - 0.508, p < 0.001). Multivariate analysis demonstrated positive associations between WOD and GerdQ (p < 0.0001), Borg score (p < 0.0005), and total Warrick score (p = 0.019). An increased oesophageal diameter (> 11 mm) on chest HRCT is associated with pulmonary and oesophageal symptoms, more severe ILD, and lower DLco.