Familial (F) and Idiopathic (I) are overlapping diagnostic subclasses of WHO Group 1 pulmonary arterial hypertension (PAH). The majority of FPAH patients have mutations in genes that code for TGFbeta cell surface receptors, and thus FPAH may present a unique phenotype. The purpose of the present study was to compare clinical characteristics of FPAH and IPAH patients enrolled in a large US-based registry, the Registry to EValuate Early And Long-term PAH Disease Management (REVEAL).
REVEAL enrolled consecutively screened patients diagnosed with WHO Group I PAH (confirmed by right heart catheterization) at 54 academic and community centers distributed evenly across 4 US census regions. We compared demographic characteristics and survival of FPAH and IPAH patients.
FPAH (n = 81) and IPAH (n = 1266) patients differed with respect to mean age at diagnosis (38 and 47 years, respectively; P < 0.0001) due, in part, to shorter times from first symptom to diagnostic catheterization (6.4 and 12.9 months, respectively; P = 0.004). Although younger when diagnosed, FPAH patients had more severe hemodynamic abnormalities, including lower CI (1.9 ± 0.7 and 2.3 ± 0.9 L/min.m2, respectively; P = 0.002) and higher mPAP (57 ± 14 and 53 ± 14 mmHg, respectively; P = 0.004) and PVRI (29 ± 13 and 23 ± 12 units.m2, respectively; P < 0.0001). More FPAH patients were treated with parenteral prostacyclin analogues (51% vs 35%, P = 0.004). Two-year survival from enrollment was 80% in FPAH and 87% in IPAH patients (P = 0.14). Two-year freedom from hospitalization was 55% in FPAH and 62% in IPAH patients (P = 0.46).
In the United States, although FPAH patients are diagnosed at an earlier age than IPAH patients FPAH patients have more severe hemodynamic abnormalities. However, two years from enrollment, similar proportions of FPAH and IPAH patients remained alive and free from hospitalization; whether this is due to more aggressive treatment of FPAH patients needs further evaluation.
Although FPAH is diagnosed at an earlier age, severe hemodynamic abnormalities at the time of FPAH diagnosis suggest the need for more active surveillance of family members at risk to develop PAH.
C Elliott, Grant monies (from industry related sources) Greg Elliott is employed by Intermountain Healthcare, which has received grant support from Actelion, United Therapeutics, Pfizer and Gilead. Robyn Barst has received grant research from Actelion, Eli Lilly, Gilead, Novartis, and Pfizer.; Consultant fee, speaker bureau, advisory committee, etc. Greg Elliott serves as a consultant to Actelion. Robyn Barst serves as a consultant to Actelion, Eli Lilly, Gilead, Novartis, and Pfizer. David Badesch has served as a steering committee member, an advisory board member, and/or a paid consultant to the following entities in the area of pulmonary hypertension: Actelion, Pfizer, Gilead, United Therapeutics/Lung Rx, Lilly/ICOS, GSK, and MondoBiotech/mondoGEN.; Other Michelle Turner is an employee of ICON Clinical Research, a company which receives research funding from Actelion and other pharmaceutical companies.; No Product/Research Disclosure Information