Evolving Concepts in Progressive Pulmonary Fibrosis: A Clinical Update

Progressive pulmonary fibrosis (PPF) is a clinical syndrome associated with worsening quality of life and increased mortality among patients with various interstitial lung diseases. This review aims to update the concepts and criteria that adequately define PPF, aiming to facilitate earlier recognition and optimize clinical management. Fibrosing interstitial lung disease (ILD-f) can progress over time despite optimal management of the underlying conditions. Current criteria for defining PPF include worsening respiratory symptoms, decline in pulmonary function tests (particularly forced vital capacity and diffusing capacity), and radiographic progression over a 1-year follow-up period. However, implementation of these criteria in clinical practice poses challenges. This review discusses the limitations of current evaluation methods and proposes future directions, including the need for validated symptom assessment tools, standardization of pulmonary function testing, and improvements in quantitative radiological evaluation methods.