The Perception of Asthma, Chronic Obstructive Pulmonary Disease, Asthma and Chronic Obstructive Pulmonary Disease Overlap, and Cough Variant Asthma: A Retrospective Observational Study.

Objective The prevalence rates of bronchial asthma (BA) and chronic obstructive pulmonary disease (COPD) are 3-11% and 8-16%, respectively, in the general Japanese adult population. Few reports on patients' perceptions of BA, cough variant asthma (CVA), COPD, and asthma and COPD overlap (ACO) are available in Japan, and we aimed to investigate the agreement between the perception and diagnosis of BA and COPD-related diseases. Methods The subjects were 229 datasets matched to the sex and age distribution of the Japanese population of 1,000 adult patients who underwent respiratory function tests and screening for each disease at Nagasaki University Hospital between July 2014 and July 2017. The patients' self-perceptions of diagnosed BA, CVA, COPD, emphysema, chronic bronchitis, and ACO were determined. Results In total, 229 datasets were included in this study. The prevalence of BA was 10.0% (23 cases, including 2 CVA and 6 ACO cases) and 11.8% (27 cases, including 6 ACO cases). The prevalence of ACO was 2.6% (28.6% of BA and 22.2% of COPD), and that of CVA was 0.9% (8.7% of BA). The perception of COPD-related diseases had a much lower sensitivity than that of asthma-related diseases (0.481 vs. 0.995, p<0.0001). Cohen's kappa for asthma-related disease was 0.976, and that for COPD-related disease was 0.621. Conclusion Self-perception of asthma-related disease was adequately high, whereas that of COPD-related disease was low. The prevalence rates of BA, COPD, ACO, and CVA in our study were 10.0%, 11.8%, 2.6%, and 0.9%, respectively. An increase in the perception of COPD may help improve community healthcare for respiratory diseases.