Life satisfaction and cardiovascular reactivity to mental stress

Abstract

Background: Satisfaction with life has been considered a health protective variable, which could impact cardiovascular morbidity and mortality. However, there is a lack of studies examining the physiological pathways involved in the potentially salutary effect of life satisfaction. We hypothesized that life satisfaction should be associated with a cardiovascular response profile signaling challenge (i.e., higher cardiac output, lower peripheral resistance) rather than threat appraisals during a mental stress task. Methods: A sample of 61 healthy men without clinical signs of psychological disorders participated in the study. They were working full-time in a highly demanding position and performed two mental stress tasks (n-back) with a varying degree of difficulty. The task was embedded between a baseline and recovery period. Cardiovascular and hemodynamic variables (heart rate, heart rate variability, blood pressure, stroke volume cardiac output, total peripheral resistance) were recorded by means of impedance cardiography (Task Force Monitor, CNSystems). Findings: Life satisfaction was associated with elevated heart rate variability throughout the experimental session, indicating higher vagal tone with increasing life satisfaction. Moreover, individuals who were more satisfied with their life showed higher cardiac output and lower peripheral resistance during the stress tasks, indicating a challenge rather than a threat profile. Findings were robust when controlling for physical activity, smoking, age, and depressive symptoms. Discussion: Life satisfaction might be accompanied by beneficial cardiovascular stress reactivity, indicating a more adaptive way to cope with stress. Thus, beneficial cardiovascular stress reactivity could constitute one route through which life satisfaction could foster health.