Rationale: Pulmonary arterial hypertension in association with connective tissue disease (CTD-PAH) has historically had a poor prognosis, with a 1-year survival rate among patients with systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH) of 45%. However, more therapies have become available.
Objectives: To investigate the survival and characteristics of all patients diagnosed with CTD-PAH in the U.K. pulmonary hypertension service.
Methods: National registry of all incident cases of CTD-PAH diagnosed consecutively between January 2001 and June 2006.
Measurements and main results: Patients with CTD-PAH (429; 73% SSc-PAH) were diagnosed by a catheter-based approach. One- and 3-year survival rates were 78 and 47% for patients with isolated SSc-PAH. Survival was worse for those with respiratory disease-associated SSc-PAH (3-yr survival, 28%; P = 0.005) whereas survival among patients with exercise-induced SSc-PAH was superior (3-yr survival, 86%; P = < 0.001). Age, sex, mixed venous oxygen saturation, and World Health Organization functional class were independent predictors of survival in isolated SSc-PAH. Nineteen percent of patients with exercise-induced SSc-PAH and 39% of patients with isolated SSc-PAH who were in functional classes I and II had evidence of disease progression. The prevalence of diagnosed SSc-PAH is 2.93 per 1 million. The 3-year survival rate of 75% for those with pulmonary arterial hypertension associated with systemic lupus erythematosus (SLE-PAH) was significantly better than that for patients with SSc-PAH (P = 0.01).
Conclusions: Survival of patients with SSc-PAH in the modern treatment era is better than in historical series. A significant proportion of patients with mild functional impairment or exercise-induced SSc-PAH have evidence of disease progression. Survival of patients with respiratory disease-associated pulmonary hypertension is inferior. SLE-PAH has a better prognosis than SSc-PAH.