Screening for Pulmonary Arterial Hypertension in Patients With Systemic Sclerosis: Clinical Characteristics at Diagnosis and Long-term Survival
Humbert M, Yaici A, de Groote P, et al
Arthritis Rheum. 2011;63:3522-3530
Pulmonary Artery Hypertension in Systemic Sclerosis
Pulmonary arterial hypertension (PAH) is a leading cause of mortality in patients with systemic sclerosis (SSc). Once commonly thought to be a late complication of SSc, support for PAH as an early manifestation of disease is growing. PAH is present within 5 years of the onset of the first non-Raynaud symptoms of SSc in approximately 50% of patients. Hope that early identification of patients with SS and PAH may lead to improved outcomes prompted Humbert and colleagues to evaluate the utility of an early detection approach vs routine care in the identification of PAH in patients with SSc.
This study from France, sponsored by Actelion Pharmaceuticals, identified 2 cohorts of patients with SSc and PAH from 2 registries. The "routine cohort" comprised patients with SSc and newly identified PAH that was initially suspected because of clinical symptoms (dyspnea, fatigue, chest pain, or edema). The "detection cohort" included patients with SSc whose PAH was found on a screening echocardiogram that showed a peak tricuspid regurgitation jet velocity greater than 3 m/sec in the absence of cardiopulmonary symptoms, or 2.5-3 m/sec plus unexplained dyspnea. In both cohorts, PAH was confirmed by right-heart catheterization as a mean pulmonary artery pressure 25 mm Hg or greater at rest and a mean pulmonary artery wedge pressure less than 15 mm Hg. All patients identified with incident PAH were enrolled in their respective cohorts during 2002-2003. Patients who had evidence of severe obstructive or restrictive disease, hypoxia, or venoembolic disease were excluded, resulting in a final sample of 32 patients (16 per cohort).
The baseline characteristics of these cohorts were compared, and their clinical courses were followed over 8 years. During this follow-up period, PAH was managed by the patients' treating physicians and was not dictated by the study protocol.
At baseline, both cohorts were similar in age (mean, 63 years), sex (> 75% women), and time since their first non-Raynaud symptom (13 years). Only 13% of the routine cohort had diffuse SSc, compared with 50% of the detection cohort. New York Heart Association (NYHA) functional class status was also better in the detection cohort, and right-heart catheterization pressures were lower in the detection cohort than the routine cohort. Patients in the routine cohort were more likely to receive warfarin and diuretic therapy, although there were no significant differences between the groups in use of oxygen or vasodilators (including prostacyclin, endothelin receptor antagonists, or phosphodiesterase inhibitors). Over the 8 years of the study, 81% of the routine cohort and 31% of the detection cohort died; the predominant cause of death (83% overall) was refractory right-sided heart failure. When patients in each cohort who were in NYHA functional class 3 at time of diagnosis were analyzed (11 in the routine cohort and 8 in the detection cohort), the overall survival rates of the detection cohort were higher.
The investigators concluded that screening patients with SSc identified milder forms of PAH, allowing earlier management and improving long-term survival.