Childhood adversity linked to altered physical response during stress

A research study involving 159 undergraduate students, published in Psychophysiology, reveals that individuals who experienced childhood adversity, such as neglect, abuse, or household dysfunction, exhibit an altered physiological response to stress compared to those without such experiences. Specifically, these individuals showed reduced blood pressure spikes and slower restoration to normal levels during a stressful task.

The muted blood pressure reaction and slower recovery could be factors contributing to the higher risk of heart disease observed in adults who faced adverse childhood experiences (ACEs). ACEs encompass various traumatic events occurring before the age of 18, ranging from physical and emotional abuse to exposure to family members with mental illness or substance use disorders.

Public health experts have long connected early traumas to numerous adverse health outcomes, including an elevated risk of cardiovascular disease. Researchers have proposed several biological mechanisms linking childhood adversity to long-term cardiovascular issues. One prominent focus is the autonomic nervous system, which governs unconscious physiological functions, including the stress response.

Historically, it was assumed that only an exaggerated stress response posed risks to the cardiovascular system. However, recent evidence suggests that a diminished physiological reaction to stress may also indicate dysregulated systems. This blunted response, potentially an evolutionary adaptation, could have both short-term survival advantages and long-term negative effects on the body's physiological flexibility.

To test these theories, Aisling M. Costello from Schreiner University, Alyndra Plagge from Trinity University, and Adam O’Riordan from the University of Texas San Antonio conducted a study. They recruited 159 young adults for a single laboratory visit, instructing them to avoid alcohol, vigorous exercise, caffeine, and food for several hours before the study to ensure baseline health behaviors did not interfere with physiological measurements.

During the experiment, participants sat in a chair with a blood pressure cuff monitoring their cardiovascular responses while completing a ten-minute resting period to establish a baseline. Their cardiovascular metrics, including heart rate, systolic and diastolic blood pressure, were tracked. Subsequently, participants completed the Trier Social Stress Task, a psychologically demanding exercise where they were asked to subtract 13 from 1,022 and state the answers aloud for six minutes, monitored by two research assistants.

If a participant made a mistake or took too long, they had to restart. After the task, participants rated their stress levels again, and then spent 15 minutes recovering while their blood pressure and heart rate were continuously recorded. Participants also completed a survey assessing their history of ACEs, scoring from zero to ten across various categories of early life trauma.

The findings showed that participants with a higher number of ACEs experienced smaller increases in systolic and diastolic blood pressure during the stress task, indicating a blunted physiological response to stress. However, this blunted response was not observed in heart rate or mean arterial pressure. Notably, although participants with ACEs reported similar levels of psychological stress, their cardiovascular reactions differed significantly.

Additionally, the researchers observed poorer recovery of diastolic blood pressure in participants with ACEs, suggesting a potential impairment in the body's physiological flexibility over time.