Hypertension and obesity after the menopause

It is well known that in pre-menopausal women the incidence of cardiovascular events is lower than in men of the same age and that after the menopause cardiovascular morbidity and mortality in women become similar, if not higher, than that in men indicating that female sex hormones play a relevant protective role upon the vasculature. Among the cardiovascular risk factors, hypertension appears to be more prevalent in postmenopausal women than in men but the precise mechanism through which menopause favours the development of hypertension is still a matter of debate. The prevalence of obesity and being overweight is also higher in postmenopausal women than that in men of comparable age. The pathogenesis of obesity-related hypertension recognizes a multifactorial mechanism including overactivity of the sympathetic nervous system, insulin resistance, leptin resistance, overactivity of the renin-angiotensin-aldosterone system and, finally, a blunted biological activity of the natriuretic peptides. The latter mechanism has been investigated by our group in recent years. Adipose tissue has been shown to express large amounts of mRNA for the biologically inactive C-type natriuretic peptide receptor (NPr-C) and this expression is decreased by fasting. Accordingly, adipose tissue can participate in the development and maintenance of high blood pressure through a reduced bioavailability of circulating natriuretic peptides leading to sodium retention. Since being overweight and obesity are a common finding in postmenopausal women, the complex mechanism of obesity-related hypertension can play a relevant role in explaining the high prevalence of hypertension after the menopause.