[Influence of Clinical Practice Guidelines on the Diagnosis and Treatment of Idiopathic Pulmonary Fibrosis. Data from the Registry of the Spanish Society of Pulmonology and Thoracic Surgery].

Objective: The objective of the study was to analyze the diagnostic process and the time until the start of treatment of patients with idiopathic pulmonary fibrosis in relation to the publication of successive clinical practice guide. Material and methods: Multicenter, observational, ambispective study, in which patients includes in the idiopathic pulmonary fibrosis registry of the Spanish Society of Pulmonologist and Thoracic Surgery were analyzed. An electronic data collection notebook was enabled on the society's website. Sociodemographic and clinical variables were collected at diagnosis and follow-up of the patients. Results: From January 2012 to december 2019, 1064 patients were included in the registry, with 929 finally analyzed. The diagnosis process varied depending on the year in which it was performed, and the radiological pattern observed in the high-resolution computed tomography. Up to 26.3% of the cases (244) were diagnosed with chest high-resolution computed tomography and clinical evaluation. Surgical biopsy was used up to 50.2% of cases diagnosed before 2011, while it has been used in 14.2% since 2018. The median time from the onset of symptoms to diagnosis was 360 days (IQR 120-720), taking more than 2 years in the 21.0% of patients. A percentage of 79.4 of patients received antifibrotic treatment. The average time from diagnosis to the antifibrotic treatment has been 309 ± 596.5 days, with a median of 49 (IQR 0-307). Conclusions: The diagnostic process, including the time until diagnosis and the type of test used, has changed from 2011 to 2019, probably due to advances in clinical research and the publication of diagnostic-therapeutic consensus guidelines.