Alveolar nitric oxide is related to periostin levels in idiopathic pulmonary fibrosis

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive diffuse lung disease leading to chronic respiratory failure and death in 3-5 years. Among potential prognostic biomarkers, alveolar nitric oxide (CaNO) and serum periostin showed to predict mortality and disease progression in these patients. The aim of this study is to investigate potential correlations between CaNO and serum periostin and evaluate their prognostic value. Methods: 59 patients with IPF (47 males, 65.5 ± 9.5 years old) were recruited in Siena Regional Referral Centre for Interstitial Lung Disease. In this population, we retrospectively collected multiple- flows exhaled nitric oxide parameters and serum periostin at diagnosis and compared these values with a control group of 60 and 8 healthy volunteers, respectively. Clinical, functional and survival data were collected according to our Centre follow-up program. Results: IPF patients reported higher levels of CaNO but not of periostin in respect with healthy controls (p < 0.0001 and p = 0.1096, respectively). CaNO significantly correlated with periostin levels and TLCO% (p < 0.0001 and p = 0.0205, respectively). Patients with CaNO > 6 ppb showed a worse prognosis, close to statistical significance (p = 0.0628). No difference in survival time was found according to periostin levels. Conclusions: CaNO was significantly higher in IPF patients and was related to functional severity of disease. CaNO levels correlated with periostin, suggesting a potential common pathway between the biomarkers.