Epidemiology and clinical characteristics of progressive pulmonary fibrosis in Asia

Progressive pulmonary fibrosis (PPF) represents a progressive phenotype across various fibrosing interstitial lung diseases (ILDs). The epidemiology of PPF is confounded by differences in the defining criteria for PPF, data capture sources, as well as the heterogeneity of ILD subtype diagnoses. In Asian PPF cohorts, although some heterogeneity exists across countries, connective tissue disease (CTD)–associated ILD is the most frequently identified underlying cause of PPF. Within CTD-ILD, rheumatoid arthritis–associated ILD and myositis-related ILD account for a particularly large proportion of patients who develop PPF. From a prognostic standpoint, PPF is consistently associated with high mortality, similar to that of idiopathic pulmonary fibrosis. Although randomized trials have demonstrated the efficacy of antifibrotic therapy in PPF, real-world use remains inconsistent because of differences in regulatory approval, reimbursement, and clinical practice. These observations underscore critical gaps in data comparability and treatment access. This narrative review synthesizes contemporary data from Asian PPF cohorts to delineate the epidemiology, clinical features, regional heterogeneity, treatment patterns, and prognosis of PPF.