The Correlation Between HRCT Phenotypes and Spirometric Indices in Patients with COPD


Background: Chronic Obstructive Pulmonary Disease (COPD) is a preventable and control-lable inflammatory respiratory disease that is a leading cause of morbidity and mortality worldwide. Objectives: The current study aimed to investigate COPD phenotypes by high resolution computed tomography (HRCT) and compare these phenotypes and other CT findings with the severity of Spirometric variables.Patients and Methods: A cross-sectional study was performed on 56 patients with COPD of any duration and smoking history referred to the radiology department of Al-Imamain Al-Kadhimain Medical city, during the period from May 1 to December 31, 2019. Spirometry was performed at the same visit during which chest HRCT was imaged, and two independent radiologists and findings interpreted these images were evaluated according to the modified Bhalla scoring system. Results: From 56 patients included in the study, 47 (83.9%) patients exhibited morphological CT changes. Patients with HRCT changes were classified into three phenotypes: Emphysema dominant (n=19), airway dominant (n=18), and mixed phenotype (n=10). Except for forced expiratory volume in 1 second to forced vital capacity ratio (FEV1/FVC), other spirometric variables, including severity stages termed the global initiative for chronic obstructive lung disease (GOLD), showed no significant correlation to the correspondent phenotypes. In con-trast, HRCT findings, including those scored according to the modified Bhalla system, were significantly correlated to the CT phenotypes. On the other hand, GOLD severity showed no correlation with the presence or severity of morphological lung changes detected on HRCT.Conclusion: The GOLD stages of COPD severity based on spirometry are not correlated with radiological phenotypes recognized on HRCT or the severity of those morphological changes. In contrast, a significant correlation was found between COPD phenotypes charac-terized on CT and the severity of morphological abnormalities.