Impact of sex on brain-heart crosstalk during acute mental stress
Bibliographic record
Abstract
Abstract Background Despite significant advancements in cardiovascular disease (CVD) management, women continue to experience worse outcomes than men, suggesting the presence of sex-specific mechanisms in cardiovascular risk. Mental stress has emerged as a critical factor influencing CVD, with increased neural activity in the amygdala—a key stress center in the brain—being linked to adverse cardiovascular events. However, little is known about how men and women differ in their heart-brain stress responses. This prospective study aimed to investigate sex differences in amygdala and myocardial responses to acute mental stress, focusing on the role of the hypothalamus-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS) activation. Methods Sixty-four healthy volunteers, evenly distributed by sex and aged between 50 and 75 years, were recruited. Participants underwent hybrid positron emission tomography/magnetic resonance (PET/MR) imaging to assess amygdala metabolism using [18F]FDG and amygdala perfusion using [13N]NH3. Myocardial blood flow (MBF) and flow reserve (MFR) were also measured. Acute stress was induced using the Trier Social Stress Test (TSST) and the Montreal Imaging Stress Task (MIST) while hybrid PET/MR imaging was performed. Additionally, stress-related hormonal and autonomic responses were evaluated by measuring salivary cortisol as an indicator of HPA-axis activation and heart rate response (HRR) as a marker of SNS activation. The primary endpoint of the study was the assessment of sex differences in stress-related neural activity (SNA), quantified as the amygdala-to-cerebellum [18F]FDG uptake ratio. Results Women exhibited significantly higher amygdala activity in response to acute mental stress compared to men (0.7530 vs. 0.7173, p<0.001), indicating a heightened neural response to stress. Stress-induced amygdala perfusion decreased significantly in women (Δ=-0.0181, p<0.001), while the reduction in men was smaller and did not reach statistical significance (Δ=-0.0086, p=0.064). Women demonstrated a higher resting myocardial blood flow (p=0.019), but there was no significant difference in myocardial flow reserve between sexes (p=0.537). Men exhibited a significant increase in cortisol levels following stress exposure (p=0.034), suggesting greater activation of the HPA axis, whereas women had a more pronounced HRR (p=0.049), indicating a stronger SNS response. Conclusion The findings of this study reveal distinct sex differences in the heart-brain stress response. Healthy women exhibit a stronger amygdala response to acute mental stress and predominantly activate the SNS, while men engage the HPA axis more substantially. These differences in neural and cardiovascular stress responses highlight the need for sex-specific approaches in cardiovascular risk assessment and interventions aimed at mitigating the impact of psychological stress on heart health.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".