Loneliness mediates the association between trait social anxiety and cardiovascular reactivity to acute psychological stress

Abstract

The primary aims of the current study are (1) to examine the association between trait social anxiety and cardiovascular reactivity to acute psychological stress, and (2) to identify if loneliness significantly mediates the association between trait social anxiety and cardiovascular reactivity. A sample of 658 participants completed a cardiovascular reactivity protocol consisting of a resting baseline and stressor phase (mental arithmetic and Stroop), with systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) monitored throughout. Participants also completed self-reported measures assessing social anxiety and loneliness. Social anxiety was associated with increased self-reported stress. However, no significant associations between social anxiety and measures of cardiovascular reactivity were observed in regression analyses. Loneliness was significantly associated with lower SBP and DBP reactivity. Additionally, loneliness significantly mediated the association between trait social anxiety and both SBP reactivity and DBP reactivity. Here, trait social anxiety predicted greater levels of loneliness, which in turn was associated with diminished cardiovascular reactivity. No significant associations emerged for HR reactivity. These blunted blood pressure responses to acute stress may indicate a potential mechanism leading to adverse prospective health outcomes.