Type D personality and cardiovascular reactivity to acute stress: The mediating effects of social support and negative social relationships.

Type D personality has been consistently associated with adverse cardiovascular health with atypical cardiovascular reactions to psychological stress one potential underlying mechanism. As Type D individuals have been noted to report lower social support and greater perceptions of negativity in social interactions, this study examined if the association between Type D personality and cardiovascular reactivity was mediated by these social relationships. A sample of 195 undergraduate students (138 female) participated in this observational study, where they completed measures assessing Type D personality (DS14), social support, and perceptions of negative social relationships (National Institute of Health social relationship scales), before undergoing a traditional cardiovascular reactivity protocol. Systolic and diastolic blood pressure (SBP; DBP), heart rate (HR), cardiac output (CO), and total peripheral resistance (TPR) were monitored throughout. ANCOVAs and regressions indicated that Type D personality was associated with lower cardiovascular reactivity to a mental arithmetic stressor. Furthermore, mediation analyses (process macro) indicated that the relationship between Type D personality and cardiovascular reactivity was mediated via increased perceptions of negative social relationships, as well as lower levels of social support. Apart from a significant association between Type D personality and increased HR reactivity, all results failed to withstand adjustment for the individual effects of negative affect (NA) and social inhibition (SI) in controlled analyses. Overall, these findings suggest that the predictive utility of Type D personality on cardiovascular reactivity above and beyond the individual effects of NA and SI is limited, and may vary depending on the cardiovascular parameter of focus.