Blunted Cardiovascular Reactivity to Mental Stress in Black Americans With a Previous Myocardial Infarction: Impact of Childhood Trauma
Authors: Martin Zachary , Fields Nicole , Shah Amit , Elon Lisa , Lewis Tené , Murrah Nancy , Shallenberger Lucy 
Published: May 2024

BACKGROUND: Black Americans who survive a myocardial infarction (MI) experience more psychosocial stress in each stage of life and are more likely to have adverse cardiovascular outcomes than Americans from other racial/ethnic groups. Childhood trauma is associated with blunted cardiovascular reactivity to mental stress, which indicates dysregulation in the stress response system and predicts adverse cardiovascular outcomes. We tested the hypothesis that childhood trauma would be a stronger predictor of blunted cardiovascular reactivity to mental stress among Black relative to White Americans with a previous MI. METHODS: We studied 185 White and 314 Black Americans with a history of MI. Childhood trauma was assessed via the Early Trauma Inventory (range, 0-27), and an established cut point of 7 identified low or high childhood trauma. Heart rate (HR) and blood pressure were measured throughout baseline and a public speaking mental stress task. Based on existing studies, blunted HR, systolic blood pressure, and diastolic blood pressure reactivity (HRR, SBPR, and DBPR) were defined as absolute responses in the lowest quartile. With the lowest risk group (White patients with low childhood trauma) as the referent, we used logistic regression to calculate odds ratios and 95% CIs for associations between the predictors (race/ethnicity and childhood trauma) and blunted reactivity while adjusting for resting HR and BP, sex, age, education, BMI, heart failure, beta blockers, and ACE inhibitors. Relative excess risk due to interaction (RERI) was calculated to assess effect modification of childhood trauma on racial/ethnic disparities in blunted cardiovascular reactivity (RERI > 0 indicates positive effect modification). Results: The mean age for the entire sample was 51±7 years. Black patients had greater childhood trauma scores relative to White patients (8±6 vs 7±5; p<0.01). After adjusting for resting values, Black patients had lower HRR (22±13 vs 29±16 bpm; p<0.01), SBPR (39±17 vs 45±16 mmHg; p<0.01) and DBPR (27±12 vs 29±11 mmHg; p=0.03). Among both groups, childhood trauma scores were associated with lower HRR and SBPR ( p<0.05 for both) but not DBPR ( p=0.13). Black patients with high but not low childhood trauma had higher odds of blunted HRR (OR=2.20 [1.19, 4.08]), SBPR (OR=1.91 [1.03, 3.54]), and DBPR (OR=2.50 [1.33, 4.72]). The estimated joint effect of Black race/ethnicity and high childhood trauma on blunted HRR was greater than their individual effects (RERI=1.51 [0.47, 2.55]); similar findings were observed for SBPR (RERI=0.62 [-0.40, 1.64]) and DBPR (RERI=1.08 [-0.12, 2.27]), though to a lesser extent. CONCLUSION: Black Americans with a prior MI are more likely than their White counterparts to have a blunted cardiovascular response to mental stress that is contingent on greater childhood trauma. Greater emphasis should be placed on preventing childhood trauma in Black Americans to help mitigate cardiovascular heath disparities. This research was supported by NIH grants R01HL109413 and T32HL130025. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.