The Three-Year Incidence of Pulmonary Arterial Hypertension Associated With Systemic Sclerosis in a Multicenter Nationwide Longitudinal Study in France

Objective. An algorithm for the detection of pulmonary arterial hypertension (PAH), based on the presence of dyspnea and the findings of Doppler echocardiographic evaluation of the velocity of tricuspid regurgitation (VTR) and right-sided heart catheterization (RHC), which was applied in a large multicenter systemic sclerosis (SSc) population, estimated the prevalence of PAH to be 7.85%. The aim of this observational study was to investigate the incidence of PAH and pulmonary hypertension (PH) during a 3-year followup of patients from the same cohort (the ItinerAIR-Sclerodermie Study). Methods. Patients with SSc and without evidence of PAH underwent evaluation for dyspnea and VTR at study entry and during subsequent visits. Patients in whom PAH was suspected because of a VTR of 2.8-3.0 meters/second and unexplained dyspnea or a VTR of >3.0 meters/second underwent RHC to confirm the diagnosis. Results. A total of 384 patients were followed up for a mean +/- SD of 41.03 +/- 5.66 months (median 40.92 months). At baseline, 86.7% of the patients were women, and the mean +/- SD age of the patients was 53.1 +/- 12.0 years. The mean +/- SD duration of SSc at study entry was 8.7 +/- 7.6 years. After RHC, PAH was diagnosed in 8 patients, postcapillary PH in 8 patients, and PH associated with severe pulmonary fibrosis in 2 patients. The incidence of PAH was estimated to be 0.61 cases per 100 patient-years. Two patients who exhibited a mean pulmonary artery pressure of 20-25 mm Hg at baseline subsequently developed PAH. Conclusion. The estimated incidence of PAH among patients with SSc was 0.61 cases per 100 patient-years. The high incidence of postcapillary PH highlights the value of RHC in investigating suspected PAH.