Background: Evidence from Europe and America suggests that female patients with COPD have a higher mortality rate than male patients. However, little is known about clinical features of female patients in Asia.

Aims and objectives: To find out the clinical characteristics of female COPD patients in Japan.

Methods: We used the cohort of the CAP study; a cross-sectional multicenter observational study of 1,168 COPD patients enrolled from 15 primary or secondary care facilities in Japan. We compared the clinical characteristics of female COPD patients with those of males.

Results: In 1,168 patients, 133 (11.4%) were female. Never-smoking history were significantly higher in females than males (13.4% vs 2.9%, p<0.01). Although there was no difference in age or %FEV1 between females and males, mMRC and number of exacerbations were significantly higher in females (mMRC?2; 59.4% vs 47.2%, p<0.01, number of exacerbations?2; 19.5% vs 11.8%, p=0.011). Females were more likely than males to use of home oxygen therapy and inhaled corticosteroids (16.5% vs 9.8%, p=0.016, 59.4% vs 41.8%, p<0.01, respectively). The prevalence of GOLD group B,C,D tended to be higher in females than in males (figure).

Conclusions: This study revealed differences in the clinical characteristics between female and male patients with COPD, suggesting the importance of intervention based on an understanding of females? disease background.