The role of diffusion lung capacity for nitric oxide in the management of patients with Idiopathic Pulmonary Fibrosis

<bold>Background:</bold> The interstitial lung diseases are a group of heterogenous pathologies involving the lung’s interstitium that could be evaluated by non-invasive and secure pulmonary functional techniques, like diffusion lung capacity for carbon monoxide (DLCO) and nitric oxide (DLNO) <bold>Objectives:</bold> The purpose of the present study is to evaluate the role of DLNO in patients affected by idiopathic pulmonary fibrosis (IPF) thought the correlation among clinical and functional data <bold>Methods:</bold> An observational non-randomized study has been conducted regarding patients with IPF at the Respiratory Medicine Unite of University-Hospital Policlinico of Foggia since February 2023 to December 2023. Enrolled patients performed pulmonary functions tests (PFTs), DLCO, DLNO, 6-minute walking test (6MWT), mMRC dyspnea scale and ecocardiography to esteem pulmonary arterial pressure (PAP) <bold>Results:</bold> 35 patients (24 male and 11 female) have been enrolled with an age between 41 and 82 years old (average age 67 years old). 10 patients had sign of pulmonary hypertension (PH) at echocardiography (PAPs > 35mmHg). The relation among the 6MWT and DLNO (r = 0.48, 95% CI 0.166 to 0.70, p 0.001) has been resulted statistically significant in comparisons to DLCO (r = 0.26, 95% CI 0.08 to 0.55, p 0.061). The correlation between DLNO and final saturation oxygen performed in 6MWT, mMRC, PH and FVC has been more significant compared to DLCO. The DLNO values was significant reduced compared with DLCO values, in patients with PH <bold>Conclusions:</bold> DLNO is a sensible method in the evaluation of diffusion lung capillary and pulmonary function in patient with IPF, therefore could be used as an early marker of vascular damage