Abstract
BACKGROUND: In this research project, we examined the relationship between tracheal size and respiratory function in individuals with Idiopathic Pulmonary Fibrosis (IPF). IPF is a long-term condition that affects the functioning of the lungs. METHODS: This retrospective study included 86 patients diagnosed with IPF. Tracheal and bronchial diameters were measured using high-resolution computed tomography (HRCT) and pulmonary function tests (PFTs); Force vital capacity (FVC), diffusion capacity for carbon monoxide (DLCO) and the gender, age, physiology (GAP) index was calculated. Patients were grouped according to demographic characteristics such as age, gender and smoking. RESULTS: There was a significant positive correlation between the anteroposterior (AP) and transverse diameters of the trachea in the subcricoid region and the GAP index (r = 0.318, p = 0.003 and r = 0.312, p = 0.004, respectively). Similarly, subcricoid and carina areas were significantly correlated with both GAP index (r = 0.307, p = 0.006 and r = 0.334, p = 0.003, respectively) and FVC/DLCO ratio (r = 0.218, p = 0.049 and r = 0.245, p = 0.027, respectively). The main bronchial areas were also positively correlated with the GAP index, but no significant correlation was found between FVC and DLCO values and airway measurements. Each unit increase in GAP index was associated with a 1.69-fold increase in mortality risk (p = 0.0016, 95% confidence interval: 1.22-2.34). CONCLUSION: Tracheal and main bronchial areas can be used as potential biomarkers in the assessment of disease severity and prognosis in IPF patients. In particular, the significant correlation of subcricoid and carina areas with both GAP index and FVC/DLCO ratio suggests that these measurements may be useful in the evaluation of disease progression.