Beneficial glycometabolic effects of transdermal 17-β estradiol in a population of hypertensive postmenopausal women

BACKGROUND: It is known that 17-beta estradiol, administered in the postmenopausal period, is able to positively influence blood glucose concentration, as well as the incidence of DM over time. Postmenopausal hypertensive women are a group of patients at high risk of developing diabetes mellitus. The aim of this prospective matched cohort study was to evaluate whether estrogen influences the glycometabolic profile also in postmenopausal hypertensive women. METHODS: The present study selected hypertensive postmenopausal women, treated with 17-beta estradiol administered transdermally at a dose of 50 µg per 24 hours. Hypertensive patients who were never treated with hormones served as control group. RESULTS: We compared HbA1c among 1418 postmenopausal hypertensive women: 709 treated with 17-beta estradiol, and 709 age-matched never treated with hormones. Length of the follow-up resulted in a median time of 4.5 years (25th75th percentiles=3.0-5.5 years). At baseline, the concentration of HbA1c was 5.6% in both groups. HbA1c (mean±SEM) was significantly lower at 6-months in patients treated with 17-beta estradiol (5.0±0.05%) compared with no-hormones group (5.5±0.04%); absolute decline from baseline was-0.6±0.06% with 17-beta-estradiol, compared with-0.1±0.04% (P<0.0001). New-onset DM was significantly reduced in the group of 17-beta estradiol (adjusted relative risk=2.04; 95%CI: 1.03-3.05; P=0.01). CONCLUSIONS: 17-beta estradiol significantly improved HbA1c and reduced the long-term incidence of new-onset diabetes mellitus in the postmenopausal hypertensive population.