The high resolution computed tomography in assessment of patients with emphysema following smoking cessation

The purpose of our study was to evaluate the short-term effect of changes in smoking cessation on subjects with chest high resolution computed tomography (HRCT)-diagnosed emphysema, both cross-sectionally and longitudinally. All patients participated in 3 months smoking cessation program.A detailed clinical history was taken and physical examination performed. We performed serum study, lung function testing and HRCT scanning to assess emphysema. After participation in the program, there was a significant increment in body mass index (0.88 kg/m², p <0.001). There was a significant decline in forced expiratory volume in one second (3.0 % (33 ml), p <0.001), but smaller than decline in smokers. There was also a significant decline in C-reactive protein (0.40 mg/L, p <0.001) & St. George's Respiratory Questionnaire (21, p <0.001). In CT image, there were significant decreases in mean lung density and the attenuation value separating the least 15% pixels (7.7 HU, p <0.001), but a significant increase in the percentage of the relative area of the lungs with attenuation values <-950 Hounsfield unit (1.9%, p <0.001). There were significant declines in smoking, modified Medical Research Council scale, Age-Dyspnea-Obstruction (ADO) index, Dyspnea-Obstruction-Smoking-Exacerbation (DOSE) index (all p <0.001), and exacerbation (p <0.01), but a significant increase in emphysema severity (p <0.05). This study shows the possible important change of HRCT in patients with emphysema following smoking cessation.