[Quantitative study on HRCT phenotype of the GOLD COPD assessment staging system]

To explore the HRCT phenotype of the combined COPD assessment staging system.

Ninety-four patients with stable COPD who visited during July 2013 and November 2014 were enrolled in our study. Each patient underwent pulmonary function test, chest CT examination and the symptom assessment using CAT questionnaire. According to the 2014 GOLD combined assessment method, these patients was divided into A-D group. Quantitative CT measures included % low attenuation area < 950 HU (LAA%), the inner diameter of bronchial (LD), the bronchial wall thickness, ratio of thickness and outer diameter (TDR), % wall area for bronchial external diameter (WA%). We used the square root of the body surface (√BSA) and body surface area (BSA) to adjust these parameters respectively.

All the parameters except LD/√BSA were gradually increased as airflow limited worsen, and there were significantly statistical differences (P < 0.05). Significantly statistical differences existed in the parameters but TDR or whose except TDR and WA% if we divided the patients with CAT questionnaire or the frequency of AECOPD. They correlated well with FEV1%, RV/TLC, DLCO, CAT and the frequency of AECOPD.

CT shows varying degrees of bronchial wall thickening, area increasing and emphysema.