Investigating Cardiovascular Reactivity and Recovery of Young Adults During Grief-Recall, With Self-Affirmation as Potential Intervention

Background

Grief refers to individual's emotional response to real, perceived, and anticipated loss, and is known to induce various psychological symptoms such as depression and anxiety and physical symptoms such as nausea, tension, or fatigue. If a grief reaction is prolonged and left untreated, it could lead to prolonged grief disorder and affect individuals' daily lives. More severe consequences, such as heightened mortality rates, have been observed among bereaved populations, particularly in relation to accidental, violent, and alcohol-related causes, where excess mortality ranges from 50% to 150%. These effects are more pronounced during short durations of bereavement (<6 months) compared to longer periods and are greater among younger individuals.

Grief is a kind of psychological stress that induces the fight-or-flight response, activating the autonomic nervous system (ANS) and the hypothalamic-pituitary-adrenal (HPA) axis, and in turn, promoting the elevation in the sympathetic nervous system which result in heightened heart rate, blood pressure, blood glucose levels, etc. Specifically, studies have revealed grief's influence on cardiovascular system. Cardiovascular biomarkers affected by short- and long-term bereavement include heightened cortisol levels, dysregulated HPA axis, and more. Many of the effects are long-lasting and highly determined by length of bereavement. For example, a previous study revealed that early bereavement is associated with increased 24-hour heart rate and decreased heart rate variability, and the effect is persistent through 6 months into bereavement. Studies have also shown that immediate grief (grief in response to death of a closed one within 6 months) is correlated with heightened cardiovascular reactivity (CVR) and impaired cardiovascular recovery.

Investigating grief within a laboratory setting presents methodological challenges; however, the Grief Recall (GR) interview offers a standardized approach to eliciting bereavement-related stress. Developed by Dr. Mary-Frances O'Connor at the University of Arizona, GR is an adaptation of the Anger Recall and Separation Recall tasks and utilizes a semi-structured interview to induce grief as the primary stressor. Findings indicate that GR elicits significant increases in systolic blood pressure (SBP) and diastolic blood pressure (DBP) from a resting state, with grief severity predicting the magnitude of SBP elevation. The present study builds upon this work by employing a larger sample size and expanding cardiovascular measurements beyond blood pressure to include heart rate (HR), respiratory sinus arrhythmia (RSA), and cardiac output (CO) and total peripheral resistance (TPR). This approach aims to provide a more comprehensive assessment of cardiovascular responses to grief elicitation within a controlled experimental framework.

Self-affirmation (SA) theory proposes that people are motivated to maintain a positive self-image of being worthy, stable, and capable. The theory also states that when facing threats, people engaging in self-affirmation resist negative consequences by maintaining a self-competent image. Studies have revealed that self-affirmation manipulation targets brain regions responsible for self-processing (medial prefrontal cortex and posterior cingulate cortex), as well as valuation (ventral striatum + ventral medial prefrontal cortex) systems. With increased activity in reward-related brain regions, self-affirmation has been shown in multiple studies to influence stress-related physiological responses in both laboratory and real-life settings. For example, SA significantly reduce cortisol response to laboratory stress tasks, moderated by dispositional self-resources an indicator of hypothalamic-pituitary-adrenal (HPA) axis activity, with effects further influenced by dispositional self-resources. Studies have also been conducted to show a positive buffer effect of SA test on cardiovascular outcomes. For instance, one study revealed that SA tasks attenuate cardiovascular reactivity during negative emotion induction, as evidenced by lower maximum heart rate, higher respiratory sinus arrhythmia (RSA), and overall reduced ratings of negative affect.