Detection of Airflow Limitation Using the 11-Q and Pulmonary Function Tests

Objective To investigate whether chronic obstructive pulmonary disease (COPD) screening that combines screening with questionnaires and pulmonary function testing is a useful method for the early detection of COPD. Methods A total of 3,367 subjects over 50 years of age underwent COPD screening. Two thousand five hundred and seventy-two of these subjects underwent "Ningen Dock" (a Japanese-English term for annual health checkup) examinations, regularly-scheduled checkups or screenings in outpatient clinics. Of these subjects, 795 lived in one city and one town in Nagasaki Prefecture and exhibited a score of at least 5 points on the Eleven-item pre-interview questionnaire (11-Q). The prevalence of airflow limitation in each type of examination was calculated for each gender, and the odds ratios of airflow limitation with each type of examination were obtained using the subjects who underwent "Ningen Dock" examinations as the reference group. Results The COPD prevalence was 6.5% in the "Ningen Dock" group (7.9% men, 1.8% women), 5.8% in the regularly-scheduled checkup group (7.4% men, 4.1% women), 9.8% in the screening in outpatient clinics group (12.1% men, 7.2% women) and 22.3% in the COPD screening group (31.1% men, 8.1% women), with the COPD screening group showing the highest prevalence. The odds ratios of the COPD prevalence confirmed that COPD screening is more effective for identifying airflow limitation than other types of examinations. Conclusion Conducting COPD screening with questionnaires and pulmonary function testing among the general population is a useful examination method for the early detection and treatment of COPD.