Characteristics and survival of connective tissue disease associated pulmonary arterial hypertension patients with and without interstitial lung disease / 中华风湿病学杂志

ABSTRACT

Objective To explore the characteristics and survival of connective tissue disease (CTD) patients with both of pulmonary arterial hypertension (PAH) arnd interstitial lung disease (ILD),and to compare with CTD patients with isolated PAH.Methods All adult CTD patients who visited one of the three referral centers in China with a diagnosis of PAH confirmed by right heart catheterization from July 2006 to May 2011 were enrolled.They were then divided into two groups (ILD with and without-ILD group) based on chest CT and then the comparison of baseline characteristics and survival at the endpoint of follow up were made between the two groups.T test,Mann-Whitney U test,x2 test,Kaplan-Meier survival analysis and Cox regression analysis were used for statistical analyses.Results One hundred and twenty-six patients were recruited into the study.Patients with ILD (n=27) were older than those without ILD (n=99).Lung function results including FVC [(75±18)％ vs (83±13)％,t=2.212,P=0.037] and DLCO [(54±22)％ vs (68±20)％,t=2.392,P=0.019] in ILD group were significantly wose than those without-ILD group.Although some important hemodynamic parameters such as mean pulmonary arterial pressure and pulmonary vascular resistance were better in the ILD group than the without-ILD group,Kaplan-Meier analysis showed that the short term survival of ILD group was significantly worse than that of the without-ILD group (72.7％ versus 94.7％ at 1 year and 63.6％ versus 81.1％ at 3 year,P=0.047).In ILD group,Cox regression analysis showed that SvO2 was the only independent factor for the short term survival [HR=0.19,95％CI (0.04,0.83),P=0.027],and Kaplan-Meier analysis showed patients with SvO2＜60％ had significantly lower short term survival than patients with SvO2 ≥60％ (1 and 2 year survival were 60.0％ and 40.0％ versus 92.9％ and 77.4％ respectively,P=0.002).Conclusion Patients with both PAH and ILD is a special subtype in CTD.Although with the superiority of hemodynamics,these patients have significantly worse survival than CTD patients with isolated PAH.Low SvO2 is the independent risk factor for the short term mortality in patients of CTD complicated by both PAH and ILD.More attention should be paid to these patients and the management strategy should be investigated further.