Hormone replacement therapy does not affect 24-h ambulatory blood pressure in healthy non-smoking postmenopausal women

OBJECTIVE: Controversies surrounding the physiological effects of hormone replacement therapy (HRT) currently lie at the forefront of medicine. Important interindividual factors that affect blood pressure, such as smoking, body mass and sodium intake, may account for the conflicting findings seen in studies examining the effects of HRT on blood pressure. DESIGN: The study was a randomized, double-blind, placebo-controlled trial. METHODS: The effect of combination HRT and estrogen-only replacement therapy (ERT) on ambulatory blood pressure was examined in a sample of 46 healthy, normotensive, non-smoking, non-obese postmenopausal women between 45 and 65 years of age. Twenty-four hour urinary sodium excretion was examined prior to and following treatment. The women were randomized to 3 months' treatment with HRT, ERT or placebo. RESULTS: After treatment, there were no significant effects of either HRT or ERT on daytime or night-time systolic or diastolic blood pressure. Sodium excretion was similar across the groups. There were no effects of treatment on night-time blood pressure dipping. CONCLUSIONS: The findings from this prospective treatment study support the conclusion that HRT has no significant effect on daytime or night-time blood pressure in a sample of healthy, non-smoking postmenopausal women.