Effects of menopausal hormone therapy on ambulatory blood pressure and arterial stiffness in postmenopausal Korean women with grade 1 hypertension: a randomized, placebo-controlled trial

BACKGROUND: Estrogen therapy in early menopausal women decreases the risk of coronary heart disease and parenteral, but not oral, estrogen is reported to reduce blood pressure (BP). Progestogens are typically added to estrogens to prevent unopposed endometrial stimulation. The effects of progestogen on BP have been less well studied to date. This study was conducted to explore the impacts of micronized progesterone (MP4) combined with percutaneous estradiol gel (PEG) on hemodynamics in postmenopausal Korean women with grade 1 hypertension. METHODS: Fifty-two postmenopausal women (aged 49–75 years) with systolic BP (SBP) of 140–160 mmHg or diastolic BP (DBP) of 90–100 mmHg were randomly assigned for 12 weeks to placebo (n = 16), estrogen therapy (ET) (n = 19) with PEG (0.1 %, 1 g./d), or estrogen + progestogen therapy (EPT, n = 17) with PEG and MP4 (100 mg/d). The primary endpoint was ambulatory BP and the secondary endpoints were arterial stiffness as brachial–ankle pulse-wave velocity (baPWV) and aortic parameters on applanation tonometry. RESULTS: One woman in the ET group dropped out, so 51 participants were finally analyzed. Outcome measures for ambulatory BP and arterial stiffness were not different between groups. Within-group comparisons showed that EPT significantly decreased daytime heart rate and baPWV: the changes from baseline (mean ± standard deviation) were − 2.5 ± 5.7 bpm (P = 0.03) and − 0.6 ± 1.4 m/s (P = 0.04), respectively. After adjusting for baseline, linear regression analysis revealed a significant difference in the relationship between baseline and 12-week baPWV among groups (P = 0.02). The relationship was significantly different between placebo and ET (P = 0.03) and EPT (P = 0.01), respectively, but not between ET and EPT. Additionally, pooled results of active treatments disclosed that SBP, DBP, PWV, and augmentation index at the aorta were significantly reduced relative to baseline. CONCLUSIONS: There was no difference in ambulatory BP between ET and EPT in postmenopausal Korean women with grade 1 hypertension. Further, ET and EPT similarly decreased baPWV from baseline as compared with placebo. MP4 might not adversely influence estrogen effects on ambulatory BP and arterial stiffness. TRIAL REGISTRATION: Clinical Research Information Registry, KCT0005405, Registered 22 September 2020 - Retrospectively registered, https://cris.nih.go.kr/cris/search/detailSearch.do?all_type=Y&search_page=L&pageSize=10&page=1&seq=17608&search_lang=E. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40885-021-00175-1.