The pattern and distribution of sympathetic nerve activity in patients with high cardiovascular risk

Restricted until 17 Apr. 2010. End-stage renal disease (ESRD) patients and chronic smokers are two populations characterized by sympathetic overactivity and high cardiovascular risk. These studies examine the distribution of sympathetic activity in ESRD patients, and the pattern of sympathetic activity with the ovarian cycle in female smokers. Simultaneous measurements of sympathetic activity to the muscle and skin were made in ESRD patients and compared to healthy controls. In premenopausal female smokers, sympathetic activity was measured during both the follicular and midluteal phases of the ovarian cycle. Sympathetic activity directed to muscle was significantly higher in ESRD compared to controls; however, skin activity was not elevated. This suggests that sympathetic overactivity in ESRD is not widespread, and reflects independent regulatory patterns. Female smokers exhibited an abnormal pattern of sympathetic outflow with failure to decline sympathetic activity during the follicular phase. This abnormal pattern may increase the total burden of sympathetic activity, contributing to cardiovascular risk.