Effect of mental stress on platelet function in normal subjects and in patients with coronary artery disease

The sex-dependent response to psychosocial stress and ischaemic heart disease

Stress is an important risk factor for modern chronic diseases, with distinct influences in males and females. The sex specificity of the mammalian stress response contributes to the sex-dependent development and impacts of coronary artery disease (CAD). Compared to men, women appear to have greater susceptibility to chronic forms of psychosocial stress, extending beyond an increased incidence of mood disorders to include a 2- to 4-fold higher risk of stress-dependent myocardial infarction in women, and up to 10-fold higher risk of Takotsubo syndrome-a stress-dependent coronary-myocardial disorder most prevalent in post-menopausal women. Sex differences arise at all levels of the stress response: from initial perception of stress to behavioural, cognitive, and affective responses and longer-term disease outcomes. These fundamental differences involve interactions between chromosomal and gonadal determinants, (mal)adaptive epigenetic modulation across the lifespan (particularly in early life), and the extrinsic influences of socio-cultural, economic, and environmental factors. Pre-clinical investigations of biological mechanisms support distinct early life programming and a heightened corticolimbic-noradrenaline-neuroinflammatory reactivity in females vs. males, among implicated determinants of the chronic stress response. Unravelling the intrinsic molecular, cellular and systems biological basis of these differences, and their interactions with external lifestyle/socio-cultural determinants, can guide preventative and therapeutic strategies to better target coronary heart disease in a tailored sex-specific manner.

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.

Comprehensive Quality Control of the Regenerative Therapy Using Platelet Concentrates: The Current Situation and Prospects in Japan

Platelet concentrates (PCs), represented by platelet-rich plasma (PRP), have been widely applied in the fields of regenerative and aesthetic therapies. PCs' mechanisms of action, however, are too complicated, and it is not easy to present the whole picture; besides, clinical outcomes are hardly reproducible in many cases. Therefore, several medically advanced countries seemingly intend to regulate PC therapies weakly or strictly because of the increasing popularity. Japan established laws and regulations for PC therapy in the "Act on the Safety of Regenerative Medicine" along with the "Pharmaceuticals, Medical Devices and Other Therapeutic Products Act" in 2014, which, to our knowledge, represent the strictest regulatory framework for production and therapeutic use of PCs in the world. According to these laws and regulations, PCs produced for topical use should be prepared as cell-based medicinal products, essentially as should stem cells, in accordance with their registered ("licensed" under actual conditions) standard operating procedures. Nonetheless, criteria for their quality are not standardized. In this review, we discuss the quality of PC preparations by focusing on the basic concept and regulatory framework of regenerative medicine in Japan. Within the new framework, PC therapy is regulated by a specific notification and registration system, as is stem cell therapy. In comparison with the latter, however, risk factors that hamper successful PC therapy are much fewer. Via appropriate evaluation of patients' conditions and whole-blood samples by simple and sensitive but not yet fully standardized assays, it is theoretically possible that PC quality will be controlled nearly completely. In addition to or instead of standardization of preparation protocols, standardization of preoperative examination of individual PC preparations is an urgent task for improving and guaranteeing the safety and efficacy of PC therapy.

Evidence for Stress-induced Bleeding in a Patient with von Willebrand Factor Deficiency

Literature reveals that psychological stress is related to hemostatic mechanisms and that excess stress can lead to prothrombotic events. Patients with chronic bleeding disorders report increased levels of subjective distress. The psychobiological link between stress and bleeding tendencies is rarely investigated when compared to the wealth of the studies on stress and clotting mechanisms. We present the case of a female with recurrent depressive disorder in whom episodic stress precipitated acute bleeding spells. An extensive hematopathological investigation revealed that she had von Willebrand factor deficiency. Our report adds to the literature that, apart from inducing procoagulant states, stress can precipitate bleeding episodes in patients with certain bleeding diatheses such as von Willebrand factor deficiency. The case also highlights that adequate pharmacotherapy and psychosocial interventions can yield adequate remission of both depression and bleeding spells.

Psychological sequelae of myocardial infarction

Patient with myocardial infarction (MI) are often affected by psychological disorders such as depression, anxiety, and post-traumatic stress disorder. Psychological disorders are disabling and have a negative influence on recovery, reduce the quality of life and causes high mortality rate in MI patients. Despite tremendous advancement in technologies, screening scales, and treatment strategies, psychological sequelae of MI are currently understudied, underestimated, underdiagnosed, and undertreated. Depression is highly prevalent in MI patients followed by anxiety and post-traumatic stress disorder. Pathophysiological factors involved in psychopathologies observed in patients with MI are sympathetic over-activity, hypothalamic-pituitary-adrenal axis dysfunction, and inflammation. Numerous preclinical and clinical studies evidenced a positive association between MI and psychopathologies with a common molecular pathophysiology. This review provides an update on diagnostic feature, prevalence, pathophysiology, clinical outcomes, and management strategies of psychopathologies associated with MI. Moreover, preclinical research findings on molecular mechanisms involved in post-MI psychopathologies and future therapeutic strategies have been outlined in the review.

Platelet aggregation and mental stress induced myocardial ischemia: Results from the Responses of Myocardial Ischemia to Escitalopram Treatment (REMIT) study

BACKGROUND

Mental stress-induced myocardial ischemia (MSIMI) is common in patients with ischemic heart disease (IHD) and associated with a poorer cardiovascular prognosis. Platelet hyperactivity is an important factor in acute coronary syndrome. This study examined associations between MSIMI and resting and mental stress-induced platelet activity.

METHODS

Eligible patients with clinically stable IHD underwent a battery of 3 mental stress tests during the recruitment phase of REMIT study. MSIMI was assessed by echocardiography and electrocardiography. Ex vivo platelet aggregation in response to ADP, epinephrine, collagen, serotonin, and combinations of serotonin plus ADP, epinephrine, and collagen were evaluated as was platelet serotonin transporter expression.

RESULTS

Of the 270 participants who completed mental stress testing, and had both resting and post-stress platelet aggregation evaluation , 43.33% (n=117) met criteria for MSIMI and 18.15% (n=49) had normal left ventricular response to stress (NLVR). The MSIMI group, relative to the NLVR groups, demonstrated heightened mental stress-induced aggregation responses, as measured by area under the curve, to collagen 10μM (6.95[5.54] vs. -14.23[8.75].; P=0.045), epinephrine 10μM (12.84[4.84] vs. -6.40[7.61].; P=0.037) and to serotonin 10 μM plus ADP 1 μM (6.64[5.29] vs. -27.34[8.34]; P<.001). The resting platelet aggregation and serotonin transporter expression, however, were not different between the two groups.

CONCLUSIONS

These findings suggest that the dynamic change of platelet aggregation caused by mental stress may underlie MSIMI. While the importance of these findings requires additional investigation, they raise concern given the recognized relationship between mental stress-induced platelet hyperactivity and cardiovascular events in patients with IHD.

Sex differences in platelet reactivity and cardiovascular and psychological response to mental stress in patients with stable ischemic heart disease: insights from the REMIT study

BACKGROUND

Although emotional stress is associated with ischemic heart disease (IHD) and related clinical events, sex-specific differences in the psychobiological response to mental stress have not been clearly identified.

OBJECTIVES

We aimed to study the differential psychological and cardiovascular responses to mental stress between male and female patients with stable IHD.

METHODS

Patients with stable IHD enrolled in the REMIT (Responses of Mental Stress-Induced Myocardial Ischemia to Escitalopram) study underwent psychometric assessments, transthoracic echocardiography, and platelet aggregation studies at baseline and after 3 mental stress tasks. Mental stress-induced myocardial ischemia (MSIMI) was defined as the development or worsening of regional wall motion abnormality, reduction of left ventricular ejection fraction (LVEF) ≥8% by transthoracic echocardiography, and/or ischemic ST-segment change on electrocardiogram during 1 or more of the 3 mental stress tasks.

RESULTS

In the 310 participants with known IHD (18% women, 82% men), most baseline characteristics were similar between women and men (including heart rate, blood pressure, and LVEF), although women were more likely to be nonwhite, living alone (p < 0.001), and unmarried (p < 0.001); they also had higher baseline depression and anxiety (p < 0.05). At rest, women had heightened platelet aggregation responses to serotonin (p = 0.007) and epinephrine (p = 0.004) compared with men. Following mental stress, women had more MSIMI (57% vs. 41%; p < 0.04), expressed more negative (p = 0.02) and less positive emotion (p < 0.001), and demonstrated higher collagen-stimulated platelet aggregation responses (p = 0.04) than men. Men were more likely than women to show changes in traditional physiological measures, such as blood pressure (p < 0.05) and double product.

CONCLUSIONS

In this exploratory analysis, we identified clear, measurable, and differential responses to mental stress in women and men. Further studies should test the association of sex differences in cardiovascular and platelet reactivity in response to mental stress and long-term outcomes. (Responses of Myocardial Ischemia to Escitalopram Treatment [REMIT]; NCT00574847).

Acute psychological stress as a precipitant of acute coronary syndromes in patients with undiagnosed ischemic heart disease: a case report and literature review

OBJECTIVES

Acute psychological stress causes a number of physiologic responses that can trigger acute coronary syndromes in individuals with silent coronary artery disease. The mechanisms behind this phenomena have been the subject of much speculation. The following is a case report and brief review of the literature.

METHOD

A PubMed search was undertaken using the key words stress and myocardial infarction, stress and ischemia, mental stress and coronary artery disease, psychological stress and acute coronary syndrome, and mental stress and plaque destabilization. Articles were restricted to the English language and those dating through December 2007.

RESULTS

Acute coronary syndrome is thought to be the end result of a complex mechanism involving platelet activation and endothelial dysfunction. Several studies have shown that acute mental stress leads to enhanced platelet activation and endothelial dysfunction. The mechanism behind this involves both the autonomic nervous system and the neuroendocrine response.

CONCLUSIONS

Acute psychological stress may lead to acute coronary syndromes in patients with previously silent disease. Physicians should inquire about cardiac symptoms in patients with cardiac risk factors who are experiencing psychological distress. Further research will hopefully lead to an improved understanding of the mechanism behind this process to improve therapeutic interventions.

Regulation of Hemostasis by the Sympathetic Nervous System: Any Contribution to Coronary Artery Disease?

Within the last two decades, hemostasis factors have emerged as 'new' risk factors for coronary artery disease. Historical studies on the physiology of the sympathetic nervous system (SNS) attributed accelerated blood clotting to the components of the fight-flight response. Although this has not been demonstrated, exaggerated clotting related to SNS hyperactivity might confer an increased arterial thrombotic risk. This review outlines the effects of sympathetic activation as mimicked by adrenergic infusions and as elicited by mental stress and physical exercise, and the molecular mechanisms involved. A selective review of the pertinent literature was undertaken. Sympathetic activation provokes a simultaneous increase in molecules of both the coagulation and fibrinolysis pathways within minutes, resulting in net hypercoagulability as a part of normal human physiology. Catecholamines and adrenergic receptors interact to mediate hemostatic changes. Exaggerated procoagulant changes in individuals with a preexistent atherosclerotic disease, in those experiencing ongoing stressful life circumstances and in the physically untrained might confer a thrombotic threat with sympathetic activation. Initial evidence suggests that nonselective β-adrenergic blockade may attenuate clotting acceleration upon SNS activation. Prospective studies are needed to demonstrate whether exaggerated clotting as elicited by the SNS is associated with an increased risk of cardiovascular morbidity and mortality. If confirmed, intervention studies targeted at reducing this risk, for example with drugs, psychotherapy (including stress management) and regular physical exercise, would be warranted.

Perceived stress as a predictor of the self-reported new diagnosis of symptomatic CHD in older women

This article describes one aspect of a prospective cohort study of 10,432 women aged between 70 and 75 years. After a 3-year period, 503 women self-reported a new diagnosis by a doctor of angina or myocardial infarction (symptomatic coronary heart disease [CHD]). Time one psychosocial variables (Duke Social Support Index, time pressure, Perceived Stress Scale, Mental Health Index, having a partner, educational attainment, and location of residence) were analyzed using univariate binary logistic regression for their ability to predict subsequent symptomatic CHD. Of these variables, the Duke Social Support Index, Perceived Stress Scale and the Mental Health Index were found to be significant predictors of symptomatic CHD diagnosis. Only the Perceived Stress Scale, however, proved to be a significant independent predictor. After controlling for time one nonpsychosocial variables, as well as the frequency of family doctor visits, perceived stress remained a significant predictor of the new diagnosis of symptomatic CHD in this cohort of older women over a 3-year period.