P.069 Effects of Acute Mental Stress on Peripheral Vascular Activity in Young Healthy Adults with and Without Family Predisposition of Hypertension

Abstract

A predominance of sympathetic activity has been described in patients with developed essential hypertension. We were interested to know whether the peripheral vascular activity and its changes provoked by mental stress were different in young healthy adults with family predisposition of hypertension (group A) and those without (group B). Peripheral vascular activity was assessed by measuring the finger artery compliance.

Experiments were performed on 38 healthy adults 19–24 years old (17 in group A, 21 in group B). We measured ECG, arterial blood pressure and finger artery compliance at rest, 3 minutes during standard arithmetic challenge and 3 minutes immediately after it. A noninvasive method was used to measure finger artery compliance, compliance index (CI) was calculated. There were no differences in systolic and diastolic blood pressure or in RR interval between the two groups.

Our results revealed the reduced CI in group A compared to group B (0.52±0.05 and 1.33±0.16, p < 0.05, t-test) at rest. CI decreased during mental stress in both groups, but only in group B the change was statistically different (p < 0.05, paired t-test). During mental stress the CI between both groups did not differ, but immediately after performing arithmetic challenge CI increased in both groups (p < 0.05, paired t-test) nearly to the control values (CI = 0.57±0.07 for group A and CI = 1.23±0.19 for group B) and differed statistically significant as at rest (p < 0.05, t-test).

These differences suggests that young healthy adults of group A could have increased sympathetic tonus compared to group B or there are changes in other peripheral mechanisms governing the small vascular behavior between both groups.