Assessment of endothelial dysfunction in idiopathic pulmonary fibrosis

Background: Idiopathic pulmonary fibrosis (IPF) is defined as a specific form of chronic fibrosing interstitial pneumonia limited to the lung, with the histopathology of UIP on surgical lung biopsy. Recent epidemiological evidence indicates that patients with IPF have an increased risk of cardiovascular disease. The vascular endothelium acts to maintain vascular homeostasis through multiple mechanisms, and alteration in its function precedes the development, progression and clinical expression of atherosclerosis. Aim of the work: To assess the prevalence of endothelial dysfunction in patients with idiopathic pulmonary fibrosis and its correlation with pulmonary hypertension. Subjects and methods: The study included two groups. The patient group included 30 IPF patients subdivided into 2 subgroups: Subgroup I (15 IPF cases) with pulmonary hypertension; Subgroup II (15 IPF cases) without pulmonary hypertension. The control group included 10 normal healthy individuals. Patients were subjected to written informed consent, detailed history taking, thorough clinical examination, collagen profile, arterial blood gases (PaO2, SaO2), Pulmonary function tests (spirometry), 6 min walk test, HRCT chest scan, echocardiography, and brachial artery duplex to assess endothelial dysfunction. Results: Subgroup (I) and Subgroup (II) showed a statistically highly significant difference in brachial artery flow mediated dilatation (BADFMD) and endothelium – reactive dilatation (ERD) which indicate endothelial dysfunction compared to the control group. Conclusion: This work concluded that BADFMD and ERD more affected in IPF patients regardless of presence or absence of PH than normal population. So, endothelial dysfunction is a possible link between IPF and cardiovascular disease