Premenstrual asthma and leukotriene variations in the menstrual cycle

Several authors report an increase in leukotriene C4 in the premenstrual phase in women with severe premenstrual asthma, indicating that antileukotrienes could be used in treatment. Objective: To analyse the role of leukotrienes in premenstrual asthma. Methods: A questionnaire on respiratory symptoms and peak flow during menstrual cycle was given to women of fertile age to define them as asthmatics who suffered from premenstrual asthma or not, and the degree of asthma severity (GINA 2005). PMA was defined as a clinical or functional deterioration (≥20%) in the premenstrual phase compared with the preovulatory phase. Blood samples to measure leukotriene C4 were taken during the preovulatory and premenstrual phases. Results: Blood samples were taken in 62 asthmatic women, 34 of whom (54.3%) presented PMA criteria with a premenstrual deterioration of between 20% and 40%. There was no difference in leukotriene C4 levels between the preovulatory and premenstrual phases in the women who suffered from PMA (1.50 ng/mL vs. 1.31 ng/mL; p=0.32) and those who did not (1.40 ng/mL vs. 1.29 ng/mL; p=0.62). Neither were there any differences in leukotriene levels between women with or without PMA. The results were similar for each category of asthma severity. Conclusions: Our data show that leukotriene C4 does not appear to be involved in the pathogenesis of premenstrual asthma, or support the use of anti-leukotrienes in the treatment of premenstrual asthma, at least in women with a moderate premenstrual deterioration. No differences appeared in any of the categories of asthma severity.