Menopause and the characteristics of the large arteries in a population study

In previous cross-sectional and longitudinal population studies, we found that the slope of systolic pressure on age was steeper in postmenopausal than in premenopausal women. We hypothesised that this observation could be due to a specific effect of menopause on the elasticity of the large arteries. We investigated 315 randomly selected women, aged 30 to 70 years. Based on 5.2 years of follow-up, 166 women were premenopausal and 149 menopausal (44 reaching menopause and 105 postmenopausal). These women were matched on age and body mass index with 315 men. We used a wall-tracking ultrasound system to measure the diameter, compliance and distensibility of the brachial and the common carotid and femoral arteries as well as carotid-femoral pulse wave velocity. Pulse pressure was determined from 24-h blood pressure recordings. Both in menopausal women (r = 0.37; P < 0.001) and in matching male controls (r = 0.16; P = 0.04), pulse pressure widened with increasing age. The slope of the 24-h pulse pressure on age was steeper in menopausal women than in their premenopausal counterparts (0.428 vs -0.066 mm Hg per year; P = 0.003) and than in the male controls (0.428 vs 0.188 mm Hg per year; P = 0.06). After adjustment for age, 24-h mean pressure, body mass index, antihypertensive drug treatment, smoking and the use of oral contraceptives or hormonal replacement therapy, postmenopausal women showed a higher carotid-femoral pulse wave velocity (7.77 vs 6.71 m/s; P = 0.02) and had a slightly greater diameter of the common carotid artery (7.09 vs 6.79 mm; P = 0.07) than their premenopausal counterparts. After similar adjustments, menopausal class was not significantly associated with other vascular measurements in women or with any vascular measurement in control men. In conclusion, menopause per se may increase aortic stiffness. We hypothesise that this phenomenon may contribute to the rise in systolic pressure and pulse pressure in women beyond age 50 and, in turn, may lead to a slight dilatation of the common carotid artery.