Retrospective cohort study of pulmonary arterial hypertension associated with connective tissue disease effect on patients’ prognosis

Objective The objectives of this study are to clarify clinical characteristics and recognize prognostic factors of CTD-PAH patients. Methods A retrospective cohort study of consecutive patients with documented CTD-PAH diagnosis from Jan 2014 to Dec 2019 was conducted, the ones who have other comorbid conditions that cause PH were excluded. Survival functions were plotted using the Kaplan–Meier method. Univariable and multivariable Cox regression analysis was applied to determine the survival-related factors. Results In 144 patients with CTD-PAH analyzed, the median sPAP value was 52.5 (44.0, 71.0) mmHg, the overall targeted drug usage rate was 55.6%, and only 27.5% patients were given combination. Twenty-four non-PAH-CTD patients with sPAP value were included as the control group. Compared with non-PAH-CTD groups, CTD-PAH patients had worse cardiac function, higher NT-pro BNP and γ-globulin level, and lower PaCO 2 level. Compared with the mild PAH group, the moderate-severe PAH group had worse cardiac function; increased Hb, HCT, and NP-pro BNP level; and decreased PaO 2 . Kaplan–Meier analysis showed significant difference for survival among non-PAH-CTD, mild CTD-PAH, and moderate-severe CTD-PAH groups. The univariate analyses showed that Hb, pH, and Ln (NT-pro BNP) were identified as factors significantly associated with survival, and Hb and pH showed significant association with risk of death in the multivariate model. Kaplan–Meier analysis also showed that Hb > 109.0 g/L and pH > 7.457 affected CTD-PAH patients’ survival significantly. Conclusions PAH is not rare in CTDs patients; PAH affects CTD patients’ prognosis significantly. Higher Hb and pH were associated with an increased risk of death. Key Points • Pulmonary arterial hypertension affects connective tissue disease patients’ prognosis significantly. • The significantly factors associated with survival is hemoglobin, pH, and Ln (NT-pro BNP).