2021 Volume 36 Issue 4 Pages 524-531
Objective: The progression of chronic obstructive pulmonary disease (COPD) can be prevented by proper management; therefore, early detection and treatment is crucial. However, 90% of the estimated 5.3 million COPD patients in Japan are undiagnosed. In this study, low-dose computed tomography (CT) scanning, respiratory function testing, and surveys via questionnaires were performed at the same time to screen for COPD and identify the factors contributing to COPD.
Methods: Of the 266 examinees who underwent population based low-dose CT for lung cancer screening, 123 agreed to undergo screening for COPD. Based on the COPD guidelines in Japan, forced expiratory volume (FEV)1.0％<70% was defined as airflow obstruction. The relationship between air flow obstruction and factors such as sex, age, smoking index, BMI, and percent low attenuation area (%LAA) were studied.
Results: Airflow obstruction was observed in 9 patients. In logistic regression analysis, the following factors were identified as significantly contributing to the presence of airflow obstruction: BMI (p<0.01), smoking index (p<0.05), and %LAA (p<0.05). The receiver operating characteristic curve was created by calculating the predicted values, which was estimated using a regression equation with frequent wheezing (p=0.07) and morning sputum entanglement (p=0.14) as explanatory variables. The area under the curve was 0.942, and the sensitivity and the specificity were 89% and 93%, respectively.
Conclusion: By combining questionnaires and low-dose CT examinations, COPD screening could be possible with a relatively high accuracy.
