A recently published, large-scale study from Australia has examined a potential association between menopausal hormone therapy (MHT) and high blood pressure . Because of its unexpected results, we thought we should examine the methodology of the study in order to be able to evaluate better the impact of the data.
Based on data derived from the [i]45 and Up Study of Healthy Ageing[/i] , Australian investigators have reported an increased risk of ‘having high blood pressure’ in women using menopausal hormone therapy (MHT) . Among 43,405 naturally menopausal women without a premenopausal history of hypertension, 12,443 were current or past users of MHT. Cross-sectional, self-reported data on having high blood pressure were analyzed, and odds ratios (ORs) were estimated using multiple logistic regression to adjust for age, country of origin, income, body mass index, smoking, alcohol, physical activity, prior oral contraceptive use, age at menopause, and childbirth.
Women who had ever used MHT were first diagnosed with high blood pressure 2.8 years earlier than women who had never used MHT and, as the age of the women increased, the association between MHT use and high blood pressure diminished. Among women aged < 56 years and 56–61 years, among both current and past users of MHT, the ORs ranged from 1.48 to 1.59, and the lower 95% confidence intervals (CIs) excluded 1.00; among women aged 62–70 years, the OR for past MHT users was 1.26 (lower 95% CI, 1.10). Among women aged ≥ 71 years, there were no significant associations. In all age groups below 71 years, the ORs for having high blood pressure increased with increasing duration of use; however, the association between the duration of MHT use and high blood pressure diminished with increased age.
The authors concluded that ‘high blood pressure should be conveyed as a health risk for people considering MHT use’.
Department of Public Health and Family Medicine, University of Cape Town, South Africa
Department of Medicine T, Ichilov Hospital, Tel-Aviv, Israel
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