Effects of hormone therapy on ambulatory blood pressure in postmenopausal Korean women

Background Previous studies of the effects of postmenopausal hormone therapy (HT) on blood pressure have yielded inconsistent results. Objectives To examine the impact of HT on 24-h ambulatory blood pressure. Methods A total of 67 postmenopausal Korean women (age 57.1±5.7 years) received 2 months of HT consisting of conjugated equine estrogen (CEE, 0.625 mg/day) with or without micronized progesterone (100 mg/day). Ambulatory blood pressure monitoring was performed at baseline and after HT. Subjects were divided into those with normal blood pressure (n=25) and those with high blood pressure (n=42), based on their baseline daytime blood pressure. Results Parity and body mass index were higher in the group with high blood pressure than in the group with normal blood pressure. For both systolic and diastolic blood pressures throughout the day, significant negative correlations were observed between basal blood pressure and blood pressure difference after HT. During the daytime period, HT increased systolic and diastolic blood pressures in the subjects with normal blood pressure and decreased systolic and diastolic blood pressures in those with high blood pressure. When micronized progesterone was added to the CEE treatment, the increase in daytime blood pressure in the group with normal blood pressure was abolished, and the decrease in systolic blood pressure throughout the day in the group with high blood pressure was potentiated. Conclusions HT had either blood pressure-elevating or blood pressure-lowering effects in postmenopausal Korean women, depending on basal blood pressure. CEE increased the daytime blood pressure in women with normal blood pressure, but reduced it in women with high blood pressure. Micronized progesterone may provide beneficial effects on blood pressure when combined with CEE.