Hormone replacement therapy and intima-media thickness of the common carotid artery: The Rotterdam study

Background and Purpose - Observational data suggest that hormone replacement therapy (HRT) reduces morbidity and mortality from cardiovascular disease in healthy postmenopausal women. The mechanisms underlying this protection are not entirely clear but may include inhibition of the atherosclerotic process. Methods - We Studied the association between ever use of HRT and intima-media thickness (IMT) of the common carotid artery in 1103 naturally menopausal women, aged 55 to 80 years, in the Rotterdam Study, a community-based cohort study in a suburban area of Rotterdam, Netherlands. Mean and maximum IMT of the common carotid artery were measured noninvasively with B-mode ultrasound. Results - Ever use of HRT for ≥ 1 year was associated with a decreased mean and maximum IMT compared with never users (mean IMT, 0.719 mm [SE 0.01] versus 0.742 mm [SE 0.004], P=0.03; maximum IMT, 0.952 mm [SE 0.015] versus 0.983 mm [SE 0.006], P=0.04), after adjustment for age, smoking, educational level, systolic blood pressure, and body mass index. No association was found for use <1 year (mean IMT, 0.739 mm [SE 0.013] versus 0.742 mm [SE 0.004], P=0.69; maximum IMT, 0.990 mm [SE 0.019] versus 0.983 mm [SE 0.006], P=0.75). Additional adjustment for diabetes, frequency of visits to healthcare facilities, or total and HDL cholesterol did not change these results. Conclusions - The findings of this population-based study show that ever use of HRT is associated with a decreased IMT in the common carotid artery in elderly women.