Inhaled anti-asthma therapies following hormone therapy in women: a nationwide cohort study

RESEARCH QUESTION: Does menopausal hormone therapy (HT) with exogenous oestrogens and progestogens change the use of inhaled anti-asthma medications in women with asthma? METHODS: In a population-based matched cohort study using the Danish registries, we included women with asthma aged 45–65 years from 1 June 1995 to 30 June 2018. We investigated whether HT with oestrogen and/or progestogens was associated with changes in use of inhaled anti-asthma therapies in the 12 months following initiation. We used exposure density matching to match exposed subjects with unexposed subjects on age, household income and level of education. An exposed subject was defined as receiving HT. We calculated mean dose of medications and odds ratios of increases in the 12 months following HT initiation. RESULTS: We included 139 483 women with asthma, of whom 116 014 (83.2%) were unexposed subjects and 23 469 (16.8%) exposed subjects. Mean±sd age was 53.0±5.2 years. Initiation of HT was not consistently associated with increased mean doses of inhaled corticosteroids (ICS), or long- and short-acting β(2)-agonists. Women receiving systemic oestrogens had increased odds ratios of large increases (>100 µg) in ICS at 6 months (OR 1.09; 95% CI 1.04–1.13; p<0.001) and 9 months (OR 1.07; 95% CI 1.03–1.12; p<0.001). Progestogens were protective against increases in ICS at 6 and 9 months (OR 0.87; 95% CI 0.82–0.93; p<0.001; and OR 0.86; 95% CI 0.81–0.91; p<0.001). CONCLUSION: Initiation of HT did not change the use of inhaled medications in asthma. However, detrimental effects of oestrogen, as well as beneficial effects of progestogens, cannot be excluded.