A USA-based registry for pulmonary arterial hypertension: 1982-2006

The aim of this study was to define the epidemiology of World Health Organization (WHO) Group I pulmonary arterial hypertension (PAH) in a large referral centre in the USA. The Pulmonary Hypertension Connection registry, initiated in 2004, evaluated all patients in a single USA practice from 1982-2006. For comparison, the authors divided the group by incident versus prevalent cohorts, aetiology and by treatment era. In total, 578 patients (77% female) aged 48 +/- 14 yrs were entered. Of these, 80% had class III or IV symptoms. Over time, connective tissue disease-associated PAH increased, while referrals for HIV remained low. One-third of patients were referred on calcium channel blocker therapy even though only 4.6% had an acute response to vasodilator challenge. When compared by treatment era, there were no differences in the severity of PAH. However, survival had improved over time, with a 1-yr survival of 85% in the incident cohort. In the USA, pulmonary arterial hypertension patients are still referred to tertiary centres too late. Referral of connective tissue disease is increasing, while referral of HIV remains low. Inappropriate calcium channel blocker treatment is common. Survival rates have increased but remain low suggesting that prognosis is improving but PAH is still a progressive, fatal disease.