Significance of pulmonary arterial pressure as a prognostic indicator in lung-dominant connective tissue disease

Lung-dominant connective tissue disease (LD-CTD) is a new concept for classifying the subset of patients with interstitial pneumonia who have clinical features suggesting an associated CTD, but whose features fall short of a clear diagnosis of CTD under the current rheumatologic classification systems. The impact of mean pulmonary arterial pressure (MPAP) in LD-CTD has not been sufficiently elucidated. To evaluate the survival impact of MPAP measured during the initial evaluation in patients with LD-CTD. We retrospectively analyzed the initial evaluation data of 100 LD-CTD patients undergoing pulmonary function test, 6-min walk test (6MWT), and right heart catheterization (RHC). The mean MPAP was 16.2±4.4 mm Hg, and 18 patients had MPAP≥20 mm Hg. A univariate Cox proportional hazard model showed that MPAP and several variables have a statistically significant impact on survival. With stepwise, multivariate Cox proportional analysis, MPAP (HR = 1.293; 95% CI 1.130-1.480; p