Prognostic factors in a cohort of antisynthetase syndrome (ASS): serologic profile is associated with mortality in patients with interstitial lung disease (ILD)

Abstract

The objectives of the present study were to compare the survival function of antisynthetase syndrome (ASS) Jo1-positive patients with ASS non-Jo1 patients, all with interstitial lung disease (ILD), and to evaluate other factors such as the extension of pulmonary disease and the time between the onset of symptoms and diagnosis and its association to survival in a cohort of ASS patients. Patients with ASS, all with ILD, were included. At the baseline, pulmonary function tests were realized and a high-resolution chest tomography was obtained; lung inflammation and fibrosis were measured with the Goh score and the Kazerooni index. The following autoantibodies were measured: Jo1, Ej, Oj, PL7, and PL12. Patients had to be positive for one of them in order to be included in the study. The survival function was estimated and compared with the log rank test, and the hazard ratio (HR) was estimated using Cox regression procedure. Forty-three patients were included, of which six patients died (14 %). Patients who died were different in comparison with survivors as regards the frequency of anti-Jo1 positivity: Survivors had anti-Jo1 autoantibodies more frequently (86 %) than patients who died (50 %). The univariate Cox regression analysis identified four variables associated with survival: Jo1 status, arthritis, extent of ground glass, and consolidation (inflammation) in high-resolution computed tomography (HRCT) and baseline forced vital capacity. The serological status of patients (Jo1-positive vs non-Jo1), the extent of lung inflammation in the HRCT scan, a low forced vital capacity, and arthritis are associated with survival in ASS patients.