Changes in the Characteristics and Initial Treatments of Pulmonary Hypertension Between 2008 and 2020 in Japan

Background: Pulmonary arterial hypertension (PAH) is a rare, progressive disease. The treatment landscape for PAH in Japan has evolved considerably in recent years, but there is limited knowledge of the changes in treatment practices or patient characteristics. Objectives: The aim of this study was to evaluate the changes in characteristics and initial treatments for PAH in Japan over time. Methods: This study used data from the Japan Pulmonary Hypertension Registry (JAPHR) to compare patient characteristics and treatment practices between 2008-2015 (n = 316) and 2016-2020 (n = 315). Results: The mean ± standard deviation age at diagnosis increased from 47.9 ± 16.7 years in 2008-2015 to 52.7 ± 16.9 years in 2016-2020. The mean pulmonary arterial pressure decreased from 45.4 ± 15.0 to 38.6 ± 13.1 mm Hg. Idiopathic/hereditary PAH was the most common etiology in both periods (50.0% and 51.1%, respectively). The proportion of patients prescribed oral/inhaled combination therapies increased from 47.8% to 57.5%. Oral/inhaled combination therapies were frequently prescribed to patients with congenital heart disease-related PAH (81.8%). There was no significant trend in prescribing practices based on French low-risk criteria: among patients with 0, 1, 2, 3, or 4 criteria, 53.8%, 68.8%, 52.8%, 66.7%, and 39.4% were prescribed oral/inhaled combination therapies, and 0%, 16.7%, 27.0%, 17.3%, and 15.2% were prescribed oral/inhaled monotherapies. Macitentan, tadalafil, selexipag, and epoprostenol were the most frequently prescribed drugs. Conclusions: The severity of PAH decreased over time in Japan. Oral/inhaled combination therapies were generally preferred. Physicians generally prescribed therapies after considering the patients’ hemodynamics and clinical severity.