Diaphragm dysfunction in combination with lung function decline is associated with higher mortality in idiopathic pulmonary fibrosis patients

Abstract

Idiopathic pulmonary fibrosis (IPF) is one of the most common interstitial lung diseases with poor prognosis. It is characterized by progressive worsening of dyspnea, decline in forced vital capacity (FVC) and CO diffusion capacity (TLco). Antifibrotic therapies decrease progression; still additional predictors of IPF mortality are needed. As diaphragm dysfunction might contribute to dyspnea and poor lung function we assessed its possible role influencing mortality. IPF patients (n=46, 46% men, all treated with nintedanib) with one year follow-up were analyzed. Group A (n=18) patients died during the first year, while group B (n=28) had baseline and 1 year data available. All patients underwent detailed pulmonary examination, lung function tests, 6 minute walk test (6MWT) and fluoroscopy to assess diaphragm movement. Lung function (FVC: A:55,4±18,2 vs B: 70,2±21,3%; p=0,01; TLco: A:41,2±15,1 vs. B: 68,5±21,4%; p 10% FVC decline. Nintedanib stabilized the lung function in 65% of the patients after 1 year in group B. Worse functional status (FVC, TLco), shorter distance and desaturation during 6MWT are negative predictors of survival. Decreased diaphragm movement in IPF patients with significant FVC decline is associated with higher mortality.