COPD assessment tests scores are associated with exacerbated chronic obstructive pulmonary disease in Japanese patients.

Guidelines recommend chronic obstructive pulmonary disease (COPD) assessment tests (CATs) for evaluation of symptoms and management risks. To investigate whether CAT can predict moderate or severe exacerbations in Japanese COPD patients, a single-blinded prospective study was performed. A 123 Japanese COPD patients were classified into high-CAT (n=64) and low-CAT (n=59) groups. The frequencies and periods of moderate or severe exacerbation and hospitalization were compared between the two groups. Multivariate logistic regression analysis was performed to investigate whether CAT could predict exacerbations. A receiver operating characteristic (ROC) curve analysis was employed to find an appropriate CAT score for exacerbation. The high-CAT group was significantly older, had a lower body mass index, and had a lower airflow obstruction as compared to the low CAT group. The frequency of moderate or severe exacerbation (1.3±1.3 events per patient per year, p<0.0001) and hospitalizations (0.2±0.4, p=0.0202) in the high-CAT group was significantly higher than in the low-CAT group (0.4±0.7 and 0.0±0.1, respectively). Multivariate logistic regression analysis showed that both high CAT score and low airflow obstruction were independently predictive of frequent moderate or severe COPD exacerbation. ROC analysis showed that the best cut-off CAT score for moderate or severe COPD exacerbation was 8 points. Our present results indicate that COPD Japanese patients showing high CAT scores have a poor prognosis, and that the CAT score is able to predict exacerbation in Japanese COPD.