Longitudinal studies investigating impact of exogenous sex steroids on clinical outcomes in women are lacking. We investigated the association between use of hormonal contraceptives and risk of severe asthma exacerbation in reproductive-age women with asthma.
We used the Optimum Patient Care Research Database, a population-based longitudinal anonymised primary care database in the UK, to construct 17-year (1/1/2000–31/12/2016) retrospective cohort of reproductive-age
(16-45 years, N=83,084) women with asthma. Using READ codes, we defined use, subtypes, and duration of use of hormonal contraceptives. Severe asthma exacerbation was defined according to recommendation of the European Respiratory Society/American Thoracic Society as asthma-related hospitalisation, accident and emergency department visits due to asthma and/or oral corticosteroid prescriptions. Analyses were done using multilevel mixed-effects Poisson regression with QR decomposition.
The 17-year follow-up resulted in 456,803 person-years of follow-up time. At baseline, 34% of women were using any hormonal contraceptives, 25% combined (oestrogen/progestogen), and 9% progestogen-only contraceptives. Previous (incidence rate ratio [IRR] 0.94, 95%CI 0.92-0.97) and current (IRR 0.96, 95%CI 0.94-0.98) use of any, previous (IRR 0.92, 95%CI 0.87-0.97) and current use of combined (IRR 0.93, 95%CI 0.91-0.96), and longer duration of use (3-4 years: IRR 0.94; 95%CI 0.92-0.97; 5+ years: IRR 0.91; 95%CI 0.89-0.93) of hormonal contraceptives, but not progestogen-only contraceptives, were associated with reduced risk of severe asthma exacerbation compared to non-use.
Use of hormonal contraceptives may reduce the risk of severe asthma exacerbation in reproductive-age women. Mechanistic studies investigating the biological basis for influence of hormonal contraceptives on clinical
outcomes of asthma in women are required.
- Asthma exacerbation
- women, hormonal contraception
- combined hormonal
- sex hormones
- clinical epidemiology
- asthma epidemiology