Survival in Australian patients with connective tissue disease-associated pulmonary arterial hypertension.

Abstract

Aim: To determine predictors of mortality in a cohort of patients with connective tissue disease-associated pulmonary arterial hypertension (CTD-PAH). Method(s): This was a retrospective cohort study of patients with CTD-PAH recruited from six tertiary hospitals. Patients were identified using the Australian Scleroderma Screening Program database and in addition to data prospectively collected, physician records were reviewed. PAH was defined on right heart catheter findings. All patients had systemic sclerosis (SSc) or another underlying CTD. Records were censored at 31/12/09. Survival was determined using Kaplan-Meier estimates and univariate predictors of survival were determined using the Log-rank and Wilcoxon tests. Result(s): Of the 112 patients, 101 (90.2%) were female. Mean age at PAH diagnosis was 61.0 + 11.4 years. SSc was the most common underlying CTD, accounting for 101 patients (90.2%). Forty-three patients (38.4%) had coexisting interstitial lung disease (ILD). At baseline, mean six minute walk distance was 323 + 131 m and 83 patients (94.6%) were in WHO functional class III. Average duration of follow-up from PAH diagnosis was 2.7 + 1.9 years. Sixty-six patients (58.9%) received monotherapy, 13 patients (11.6%) sequential monotherapy and 32 patients (28.6%) combination therapy. Bosentan was the most commonly prescribed medication, used in 99 patients (88.4%). Sildenafil was the next most common, followed by inhaled iloprost and sitaxentan. One-, two- and three-year survival was 93.4%, 87.9% and 72.0% respectively. On univariate analysis, predictors of mortality were higher baseline WHO functional class, male sex, ILD, right ventricular dysfunction, pericardial effusion, absence of warfarin therapy and higher right atrial pressure at PAH diagnosis. Conclusion(s): In this study, three-year survival was 72%; this is better than in historical series from the pre-treatment era and is comparable with what is described internationally. Predictors of mortality include higher functional class and higher right atrial pressure at PAH diagnosis, suggesting that earlier detection and treatment may improve survival.