Mental-stress-induced platelet activation among patients with coronary artery disease

The effects of a firefighting simulation on the vascular and autonomic functions and cognitive performance: a randomized crossover study

Introduction: During firefighting, physical and cognitive demands increase. However, the stress inherent to these events can decrease cognitive performance and increase the risk of cardiovascular events in firefighters. Thus, this crossover study aimed to evaluate the effects of a firefighting Simulation on cognitive performance and vascular and autonomic functions in military firefighters. Methods: Sixteen firefighters (37.8 ± 5.6 years) underwent anthropometry, mental health status, and sleep quality assessments. They randomly performed two interventions, Simulation (Firefighting tasks; 10.0 ± 1.1 min) and Control (rest for 10 min), on different days. After both interventions, cognitive performance was assessed using the Stroop Test, Paced Auditory Serial Addition Test, and Trail Making Test. Then, the vascular function was assessed using ultrasonography through the carotid artery reactivity to the cold pressor test. The arterial pressure, heart rate, and cardiac intervals were recorded before interventions. The cardiac intervals were also measured during the cold pressor test. Student's t-test and Wilcoxon were used for comparisons between Control and Simulation and the analysis of variance for repeated measures was used for comparison over time during the cold pressor test. A significance level of p < 0.05 was adopted. Results: Although the mean and maximum heart rate were higher before the Simulation (p < 0.0001), all the heart rate variability parameters (p > 0.05) and mean arterial pressure (p > 0.3795) were similar before the interventions. After Simulation, the cognitive performance was similar to Control (p > 0.05), except for the improvement in Stroop Test part B (p < 0.0001). After Simulation, carotid artery reactivity was attenuated (p < 0.0010). During the cold pressor test, the high-frequency band of the heart rate variability was lower after the Simulation (p < 0.0104). Discussion: Although firefighting Simulation did not substantially change cognitive performance, the lower carotid artery reactivity and parasympathetic modulation to the heart during the cold pressor test may contribute to greater vulnerability to cardiovascular events in firefighters on duty.

High Perceived Stress May Shorten Activated Partial Thromboplastin Time and Lead to Worse Clinical Outcomes in Patients With Coronary Heart Disease

Objective: To determine the association of perceived stress with coagulation function and their predictive values for clinical outcomes. Methods: This prospective cohort study derived from a cross-sectional study for investigating the psychological status of inpatients with suspicious coronary heart disease (CHD). In this study, the 10-item Perceived Stress Scale (PSS-10) as an optional questionnaire was used to assess the severity of perceived stress. Coagulation function tests, such as activated partial thromboplastin time (APTT), prothrombin time (PT), and fibrinogen were measured within 1 h after admission. Furthermore, 241 patients with CHD out of 705 consecutive inpatients were included in the analyses and followed with a median of 26 months for the clinical outcomes. Results: The patients in high perceived stress status (PSS-10 score > 16) were with shorter APTT (36.71 vs. 38.45 s, p = 0.009). Shortened APTT ( ≤ 35.0 s) correlated with higher PSS-10 score (14.67 vs. 11.22, p = 0.003). The association of APTT with depression or anxiety was not found. Multiple linear models adjusting for PT estimated that every single point increase in PSS-10 was relevant to approximately 0.13 s decrease in APTT (p = 0.001) regardless of the type of CHD. APTT (every 5 s increase: hazard ratio (HR) 0.68 [0.47-0.99], p = 0.041) and perceived stress (every 5 points increase: HR 1.31 [1.09-1.58], p = 0.005) could predict the cardiovascular outcomes. However, both predictive values would decrease when they were simultaneously adjusted. After adjusting for the physical clinical features, the associated of perceived stress on cardiac (HR 1.25 [1.04-1.51], p = 0.020) and composite clinical outcomes (HR 1.24 [1.05-1.47], p = 0.011) persisted. Conclusions: For the patients with CHD, perceived stress strongly correlates with APTT. The activation of the intrinsic coagulation pathway is one of the mechanisms that high perceived stress causes cardiovascular events. This hints at an important role of the interaction of mental stress and coagulation function on cardiovascular prognosis. More attention needs to be paid to the patients with CHD with high perceived stress.

Impact of Acute and Chronic Stress on Thrombosis in Healthy Individuals and Cardiovascular Disease Patients

Psychological stress induces different alterations in the organism in order to maintain homeostasis, including changes in hematopoiesis and hemostasis. In particular, stress-induced hyper activation of the autonomic nervous system and hypothalamic–pituitary–adrenal axis can trigger cellular and molecular alterations in platelets, coagulation factors, endothelial function, redox balance, and sterile inflammatory response. For this reason, mental stress is reported to enhance the risk of cardiovascular disease (CVD). However, contrasting results are often found in the literature considering differences in the response to acute or chronic stress and the health condition of the population analyzed. Since thrombosis is the most common underlying pathology of CVDs, the comprehension of the mechanisms at the basis of the association between stress and this pathology is highly valuable. The aim of this work is to give a comprehensive review of the studies focused on the role of acute and chronic stress in both healthy individuals and CVD patients, focusing on the cellular and molecular mechanisms underlying the relationship between stress and thrombosis.

Stress Enhances Proinflammatory Platelet Activity: the Impact of Acute and Chronic Mental Stress

The role of platelets in hemostasis and thrombosis has long been recognized, recently their contribution to immunological and inflammatory processes is emerging. Platelets could be the missing link between cardiovascular disease, chronic stress and depressive symptoms. Both physical and mental stressors cause platelet activation reflected by changes in platelet bioactivity and aggregation. Here we evaluate the proinflammatory platelet response to acute and chronic mental stress. In a prospective study design an acute mental stress test was administered to 55 healthy male participants once without and once in the presence of chronic mental stress. Blood was collected prior to and at three time points following an acute mental stress test (0, 30, 60 min). Platelet proinflammatory activation markers, were assessed using FACS analysis and aggregability was measured in response to ADP or epinephrine using PFA-100. A linear mixed model was used for analysis. Chronic mental stress lead to a significant increase in state anxiety (p < 0.001), depressive symptoms (p = 0.045) and perceived stress (p = 0.001). The factor “chronic mental stress” was significantly associated with increased numbers of CD63+ platelets (p = 0.009). The factor “acute mental stress” was associated with alterations in CD62P+ platelets (p < 0.001), CD63+ platelets (p = 0.011), PAC-1+ platelets (p < 0.001) as well as platelet leucocyte aggregates (p = 0.019). The recovery of CD62P function following the acute mental stress exposure was significantly impaired by chronic stress (p = 0.023). Aggregation was affected by chronic and acute mental stress. In conclusion, mental stress is linked to an increased and prolonged proinflammatory platelet bioactivity. This proinflammatory and immunomodulatory stimuli could help to explain the link between mental and somatic disorders.

The association of depression following percutanous coronary intervention with adverse cardiovascular events: Protocol for a systematic review and meta-analysis

INTRODUCTION

Percutanous coronary intervention (PCI) has been increasingly used for patients suffered from severe coronary artery disease. However, physical trauma and potential adverse events related to the procedure often result in detrimental psychological stress. Accumulating evidences have shown that depression is closely related to coronary artery disease. However, the association of depression following percutanous coronary intervention with adverse cardiovascular events is still unknown.

OBJECTIVE

This review is designed to assess the prognostic association of depression following PCI with adverse cardiac events.

METHODS AND ANALYSIS

The following databases will be searched, PubMed, the EMBASE, CINAHL and Web of Science of English-language publications from inception to 30 October 2018. Cross-referencing from retrieved studies will be conducted additionally, and observational studies were included. Two independent review authors will do the study selection on the basis of the study eligibility criteria. Extracted data will be used for quantitative and qualitative evidence synthesis as well as to assess methodological quality of studies using the Newcastle-Ottawa checklist. The primary objective of this review is adverse cardiac events, presented as a composition of myocardial infarction, repeat coronary revascularization, cardiac readmission, and cardiac death. The accumulated evidence is evaluated and graded according to Grading of Recommendations, Assessment, Development and Evaluation (GRADE).

RESULTS AND CONCLUSIONS

This review will explain the association of depression following percutanous coronary intervention with adverse cardiovascular events, and provide physicians with scientific evidence for psychological intervention in patients after PCI.

PROSPERO REGISTRATION NUMBER

CRD42018112486.

Platelet response to serotonin in patients with stable coronary heart disease

Patients with heart disease and depression have an increased mortality rate. Both behavioral and biologic factors have been proposed as potential etiologic mechanisms. Given that the pathophysiology of depression is considered to involve disruption in brain serotonergic signaling, we investigated platelet response to serotonin stimulation in patients with stable coronary artery disease (CAD). We enrolled 92 patients with stable CAD. Platelet response to increasing concentrations of serotonin (5-HT), epinephrine-augmented 5-HT, and adenosine diphosphate (ADP) was measured by optical aggregation and flow cytometry. As concentrations of 5-HT and ADP increased, so did the activation and aggregation of the platelets. However, on addition of the highest concentration of 5-HT (30 μM), a significant decrease in platelet activation (p=0.005) was detected by flow cytometry. This contrasts the increase in platelet activation seen with the addition of the highest concentration of ADP. In conclusion, we found increased platelet activation and aggregation with increased concentrations of ADP; however, when platelets are stimulated with a high concentration of 5-HT (30 μM), there is decreased platelet activation. The data demonstrate unique patterns of platelet activation by 5-HT in patients with stable CAD. The cause of this phenomenon is unclear. Our study sheds light on the in vitro response of platelet function to serotonin in patients with stable CAD, which may further the mechanistic understanding of heart disease and depression.

Psychological factors, including alexithymia, in the prediction of cardiovascular risk in HIV infected patients: results of a cohort study

BACKGROUND

Psychological factors are known predictors of cardiovascular disease in many clinical settings, but data are lacking for HIV infection. We carried out a prospective cohort study to evaluate potential psychological predictors of preclinical and clinical vascular disease in HIV patients.

METHODOLOGY/PRINCIPAL FINDINGS

HIV patients were consecutively enrolled. Demographics, viral and immune parameters and traditional cardiovascular predictors were considered; Intima-Media Thickness (c-IMT, continuous measure) and Carotid Plaques (CPs, focal thickening ≥1.5 mm) were investigated by B-mode ultrasonography; depressive symptoms by the Beck Depression Inventory (BDI-II), Type D personality (Distressed Personality or Type D) by the DS14, alexithymia by the Toronto Alexithymia Scale (TAS-20). Vascular outcomes included transient ischemic attacks or stroke, acute coronary syndrome, myocardial or other organ infarction. We enrolled 232 HIV subjects, 73.9% males, aged 44.5±9.9 y, 38.2% with AIDS diagnosis, 18.3% untreated. Mean Nadir CD4 T-cell counts were 237.5±186.2/mmc. Of them, 224 (96.5%) attended IMT measurements; 201 (86.6%) attended both IMT assessment and psychological profiling. Mean follow-up was 782±308 days. Fifty-nine patients (29.4%) had CPs at baseline. Nineteen patients (9.5%) had ≥1 vascular event; 12 (6.0%) died due to such events (n = 4) or any cause. At baseline cross-sectional multivariate analysis, increasing age, total cholesterol, current smoking and Alexithymia score≥50 were significantly associated with both increased cIMT (linear regression) and CPs (logistic regression). At follow-up analysis, log-rank tests and Cox's regression revealed that only older age (p = 0.001), current smoking (p = 0.019) and alexithymia score≥50 (p = 0.013) were independently associated with vascular events.

CONCLUSIONS/SIGNIFICANCE

In HIV-infected subjects, the Alexithymic trait emerges as a strong predictor of increased IMT, presence of CPs and vascular events. Such results are preliminary and require confirmation from studies with larger sample size and longer follow-up.

Influence of mental stress on platelet bioactivity

It is well established that various mental stress conditions contribute, or at least influence, underlying pathophysiological mechanisms in somatic, as well as in psychiatric disorders; blood platelets are supposed to represent a possible link in this respect. The anculeated platelets are the smallest corpuscular elements circulating in the human blood. They display different serotonergic markers which seem to reflect the central nervous serotonin metabolism. They are known as main effectors in haematological processes but recent research highlights their role in the innate and adaptive immune system. Platelets are containing a multitude of pro-inflammatory and immune-modulatory bioactive compounds in their granules and are expressing immune-competent surface markers. Research gives hint that platelets activation and reactivity is increased by mental stress. This leads to enhanced cross talk with the immune system via paracrine secretion, receptor interaction and formation of platelet leucocyte-aggregates. Recently it has been demonstrated that the immune system can have a remarkable impact in the development of psychiatric disorders. Therefore platelets represent an interesting research area in psychiatry and their role as a possible biomarker has been investigated. We review the influence of mental stress on what is termed platelet bioactivity in this article, which subsumes the mainly immune-modulatory activity of platelets in healthy volunteers, elderly persons with chronic care-giving strain, patients with cardiovascular diseases who are prone to psychosocial stress, as well as in patients with posttraumatic stress disorder. Research data suggest that stress enhances platelet activity, reactivity and immune-modulatory capacities.

Childhood trauma and platelet brain-derived neurotrophic factor (BDNF) after a three month follow-up in patients with major depressive disorder

A large amount of brain-derived neurotrophic factor (BDNF) is stored in the human platelets and only small amounts of it circulate in the plasma. However, a few studies have focused on platelet BDNF in patients with major depressive disorder (MDD) and childhood trauma. Our study population consisted of 105 MDD patients and 50 healthy controls. We used the mini-international neuropsychiatric interview (M.I.N.I.), the early trauma inventory self report-short form (ETISR-SF), as well as measured serum, plasma, and platelet BDNF at baseline, 1 month, and 3 month periods. There was a significant association between childhood trauma and platelet BDNF at baseline, 1 month, and 3 months, after adjusting for age, gender, education, body mass index, severity of depression, anxiety, alcohol consumption, and current stress. Conversely, plasma and serum BDNF did not have a significant association with childhood trauma. MDD patients revealed significantly higher levels of platelet BDNF in those with childhood trauma than in those without (t = 2.4, p = 0.018), and platelet BDNF was significantly higher in cases with sexual abuse on post-hoc analysis (p = 0.042). However, no significant differences were found in healthy controls, according to whether or not they had experienced childhood trauma. Platelet BDNF showed a significant correlation with severity of childhood trauma at baseline (r = 0.25, p = 0.012) and at 3 months (r = 0.38, p = 0.003) in MDD. In conclusion, platelet BDNF was significantly higher in MDD patients with childhood trauma than in those without, and it was correlated with severity of trauma.

Hemoconcentration and hemostasis during acute stress: interacting and independent effects

BACKGROUND

Acute psychological stress can produce significant hemoconcentration as well as prothrombotic changes in blood, both of which may have potentially harmful effects on the cardiovascular system. It is unclear whether these effects are independent or have influence on each other.

PURPOSE

This review discusses research investigating the effects of acute psychological stress on hemoconcentration and hemostasis and explores future directions for psychohematology research. Physiology, associations with cardiovascular disease, and relationships between acute psychological stress are discussed independently for hemoconcentration and hemostasis, followed by an examination of the effects of stress-hemoconcentration on hemostasis.

CONCLUSIONS

Traditional methods of adjusting for stress-hemoconcentration effects (e.g., calculated plasma volume or hematocrit level corrections) may not be appropriate when examining stress-induced changes in hemostasis. The effects of acute stress on hemostasis should be examined in conjunction with hemoconcentration.