Among patients with pulmonary arterial hypertension (PAH), those with germline mutations in the gene encoding bone morphogenetic protein receptor 2 (BMPR2) present at an earlier age and with more severe hemodynamic compromise, according to findings from a French study.
Dr. Marc Humbert of Universite Paris-Sud 11 and colleagues screened 223 consecutive patients with PAH for point mutations and large size rearrangements of BMPR2. Clinical, functional and hemodynamic characteristics were compared between carriers and noncarriers.
The investigators identified 68 carriers of the BMPR2 mutation. Forty had idiopathic PAH and 28 had familial PAH. The 155 noncarriers all had idiopathic PAH.
Carriers were nearly 10 years younger at diagnosis than noncarriers, with mean ages of 36.5 years and 46.0 years, respectively, the team reports in the June 15 issue of the American Journal of Respiratory and Critical Care Medicine.
Mean pulmonary artery pressure was 64 mm Hg in carriers and 56 mmHg in noncarriers. Cardiac index was 2.13 L/min/m in carriers and 2.50 L/min/m in noncarriers. Mixed venous oxygen saturation was 59% in carriers and 63% in noncarriers.
Carriers had a shorter time to death or lung transplantation and a younger age at death than noncarriers, Dr. Humbert and colleagues report.
"Despite major advances in the treatment of PAH, the pathogenesis of this condition remains obscure," Dr. Lewis J. Rubin of the University of California at San Diego writes in an accompanying editorial. He adds, "Patients and physicians will be best served by referral to expert centers, where collaborative and translational efforts will further our understanding of this condition and lead to more effective treatments in the future."
Am J Resp Crit Care Med 2008;177:1377-1383.
Reviewed by Ramaz Mitaishvili, MD