Evolution of sleep-disordered breathing and blood pressure during menopausal transition

The purpose of this study was to investigate how the blood pressure increase observed during menopausal transition is affected by sleep-disordered breathing and the menopause itself. Further, we aimed to find new sleep-disordered breathing related markers that would predict the development of hypertension. Sixty-four community-dwelling premenopausal women aged 45-47 years were studied. Polysomnography, serum follicle stimulating hormone, forced expiratory volume in 1 s, and a physical examination were performed at baseline and again after 10 years of follow-up. Indices for sleep apnea/hypopnea and inspiratory flow-limitation were determined. Regression models were used to study the relationships between variables. Changes in the apnea-hypopnea index or serum follicle stimulating hormone were not significant for blood pressure change. An increase in morning blood pressure during the follow-up period was associated with a body mass-index increase. An increase in evening blood pressure was associated with an increase in inspiratory flow-limitation during non-rapid eye movement sleep. Incident hypertension during the follow-up was associated with hypopnea (median hypopnea index 7.6/h, p = 0.048) during rapid eye movement sleep at baseline. Users of menopausal hormone therapy had a lower rapid eye movement sleep apnea-hypopnea index (1.6/h vs. 6.9/h, p = 0.026) at baseline whereas at follow-up users and non-users did not differ in any way. The progression of menopause or the use of menopausal hormone therapy had a minimal effect on blood pressure in our population. The effects of inspiratory flow-limitation on blood pressure profile should be studied further.