Patient and Therapeutic Profiles of Pulmonary Hypertension in Chronic Lung Diseases in Japan: A Cohort Study Using a Claims Database

Pulmonary hypertension (PH) is often complicated by chronic lung diseases (CLDs) such as chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD). Differentiating between PH associated with CLD (group 3 PH) and pulmonary arterial hypertension (PAH) in CLD is often difficult and reporting on the efficacy of PAH-specific therapies is inconsistent as a result of the lack of understanding of the heterogeneity of patients with PH. A retrospective observational cohort study was conducted to understand the baseline characteristics, comorbidities, and treatment profiles of patients with PH in CLD in a real-world setting using a large-scale claims database (Medical Data Vision). Administrative and clinical data for patients admitted to acute-care hospitals in Japan between April 2008 and January 2021 were analyzed. A total of 115,921 patients with CLD (109,578 with COPD and 6343 with ILD, of whom 569 and 176 had PH, respectively) were analyzed. This study found lower PH diagnosis rates among patients with COPD and patients with ILD than in previous studies. The majority of PH with CLD patients were elderly (mean age 75.7 years) and male (80.81%). Among patients with CLD prescribed PAH-specific therapies (105 patients with COPD; 64 patients with ILD), most received these as monotherapy (COPD, 84.76%; ILD, 75.56%); the most common were phosphodiesterase 5 inhibitors (COPD, 42.70%; ILD, 18.37%), prostacyclins (oral; COPD, 48.31%; ILD, 24.49%), and endothelin receptor antagonists (ERA) (COPD, 8.99%; ILD, 18.37%). Comorbidities (e.g., pulmonary, cardiac, kidney), home oxygen therapy (HOT), and echocardiography (ECHO) were factors associated with the diagnosis of PH. This is the first study using an administrative database that provides real-world data on patients with PH in CLD in Japan. Our results indicate that PH may be misdiagnosed or underdiagnosed in Japan which may lead to suboptimal treatment for patients, and supports the need for further evidence to guide appropriate treatment. Pulmonary hypertension is a disorder affecting the arteries in the lungs and the right heart. It can be associated with a variety of heart and lung conditions, including many chronic lung diseases such as chronic obstructive pulmonary disease and interstitial lung disease. Patients with pulmonary hypertension with chronic lung disease and/or hypoxia can be hard to tell apart from patients with pulmonary arterial hypertension coinciding with chronic lung disease. In Japan, there is not enough data on patient demographics and their disease characteristics for patients with pulmonary hypertension and chronic lung disease, including treatment profiles, and disease management. We identified these patients from a large medical claims database in Japan and analyzed their data. Our study focused on the use of therapies for pulmonary arterial hypertension on patients with pulmonary hypertension and chronic lung disease. The diagnosis rates of pulmonary hypertension for patients with chronic obstructive pulmonary disease and interstitial lung disease were low compared to previous reports, meaning patients with pulmonary hypertension may be misdiagnosed or underdiagnosed which may be resulting in suboptimal treatments. Furthermore, the majority of patients with pulmonary hypertension treated with pulmonary arterial hypertension medication received a single drug as treatment, even though the guidelines recommend the use of combination therapies in certain situations. This study emphasizes the need for further evidence generation for improvements in diagnoses and treatment of patients with pulmonary hypertension in Japan.