Indices of autonomic nervous system activity in women with mild hypertension in the perimenopausal period.

BACKGROUND

Hypertension is more common after menopause. Increased incidence of hypertension can be attributed to autonomic nervous system dysfunction. The relationship between the parameters of heart rate variability (HRV), the levels of norepinephrine (NE) and leptin, and the menopausal status is still poorly understood, although there is some evidence suggesting distinct influence of estrogens on the above-mentioned indicators.

AIM

To characterise the influence of menopause on indices of autonomic nervous system activity in women with mild hypertension.

METHODS

We recruited 112 women aged 45 to 55 years with mild essential hypertension confirmed by 24 h ambulatory blood pressure monitoring. The study population was divided into two groups - postmenopausal (A, n = 61; age 51,03 +/- 1,39 years) and premenopausal (B, n = 51; age 50 +/- 2 years). None of the women had organ damage, other risk factors, inflammation diseases, were on estrogen replacement therapy or oral contraceptives. In all patients we assessed the leptin and NE levels. The HRV time-domain and spectral parameters were analysed from Holter ECG recordings.

RESULTS

After menopause we observed, among others, the lower values of total power, VLF, HF (ms, %), LF (%) and LF:HF 24 h. The level of NE as well as the concentration of leptin were higher in postmenopausal rather than premenopausal women.

CONCLUSION

Higher activity of sympathetic nervous system and higher levels of leptin in hypertensive women after menopause may suggest their participation in the pathogenesis of hypertension in this group of patients.