Analysis of perimenstrual asthma based on questionnaire surveys in Japan

Perimenstrual asthma (PMA) has been documented in 30% to 40% of asthmatic women; the characteristics of PMA have also been well described. However, there have been few epidemiological investigations of PMA in practice. In this study, we analyzed PMA based on a questionnaire survey carried out in Japan and compared the results with those of studies reported previously.

For 8 weeks from September through October 2004, a questionnaire survey was administered to patients with bronchial asthma and their attending physicians. The questionnaire surveyed asthma control, asthma-related emergencies and satisfaction in daily life. The attending physicians were questioned about patient profiles and medications. All female patients who were menstruating during the survey period and who were known to have asthma exacerbation related to menstruation were allocated to the PMA group; those who were not were allocated to the non-PMA group.

The rate of PMA in female patients who were menstruating during the survey period was 11.3% in this study. Characteristic features of the PMA group (n = 54) included more severe disease, worsened disease control and more aggressive patient management, including increased oral corticosteroid use compared with the non-PMA group. The rates of emergency episodes in the PMA group were higher than in the non-PMA group. There was a significant increase in aspirin intolerant asthma (AIA, 25.5%) in the PMA group compared with the non-PMA group (8.4%).

Attention should be paid to the lack of knowledge regarding PMA in patients with asthma in actual clinical settings. The low rate of PMA reported in this study may be due to the study method using self-reports of PMA by patients without sufficient knowledge, and may not be an accurate representation of the actual incidence of the disease. The clinical similarity of PMA to AIA in this study may also provide a new insight into the mechanism of PMA.