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KAUNAS UNIVERSITY OF MEDICINE
Aura Leonaitė-Evans
ALTERNATION OF
THE CARDIOVASCULAR SYSTEM FUNCTIONAL STATE DURING TWO RELAXATION TECHNIQUES
IN MEN AFTER MYOCARDIAL INFARCTION
Doctoral Dissertation
Biomedical Sciences, Nursing (11 B)
Kaunas, 2010
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The doctoral dissertation was prepared in 2005–2010 at Kaunas University of Medicine.
Scientific Supervisors:
2007–2010 Prof. Dr. Habil. Alfonsas Vainoras (Kaunas University of Medicine, Biomedical Sciences, Nursing – 11 B).
2005–2007 Prof. Dr. Habil. Abdonas Tamošiūnas (Kaunas University of Medicine, Biomedical Sciences, Public Health – 10 B).
Consultants:
Assoc. Prof. Dr. Algė Daunoravičienė (Kaunas University of Medicine, Biomedical Sciences, Nursing –11 B)
Assoc. Prof. Dr. Laimonas Šiupšinskas (Kaunas University of Medicine, Biomedical Sciences, Nursing –11 B).
Dr. Vytautas Zabiela (Kaunas University of Medicine, Biomedical Scien- ces, Medicine – 07 B).
2007–2010 Prof. Dr. Habil. Abdonas Tamošiūnas (Kaunas University of Medicine, Biomedical Sciences, Public Health – 10 B).
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KAUNO MEDICINOS UNIVERSITETAS
Aura Leonaitė-Evans
VYRŲ ŠIRDIES IR KRAUJAGYSLIŲ SISTEMOS FUNKCINĖS BŪKLĖS KAITA DVIEJŲ ATSIPALAIDAVIMO TECHNIKŲ
METU PO MIOKARDO INFARKTO
Daktaro disertacija
Biomedicinos mokslai, slauga (11 B)
Kaunas, 2010
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Disertacija rengta 2005–2010 metais Kauno medicinos universitete.
Moksliniai vadovai:
2007–2010 prof. habil. dr. Alfonsas Vainoras (Kauno medicinos universitetas, biomedicinos mokslai, slauga – 11 B).
2005–2007 prof. habil. dr. Abdonas Tamošiūnas (Kauno medicinos universitetas, biomedicinos mokslai, visuomenės sveika- ta – 10 B).
Konsultantai:
doc. dr. Algė Daunoravičienė (Kauno medicinos universitetas, biomedi- cinos mokslai, slauga – 11 B).
doc. dr. Laimonas Šiupšinskas (Kauno medicinos universitetas, biomedi- cinos mokslai, slauga – 11 B).
dr. Vytautas Zabiela (Kauno medicinos universitetas, biomedicinos mokslai, medicina – 07 B).
2007–2010 prof. habil. dr. Abdonas Tamošiūnas (Kauno medicinos universitetas, biomedicinos mokslai, visuomenės sveika- ta – 10 B).
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CONTENTS
ABBREVIATIONS ... 7
INTRODUCTION ... 8
Novelty, scientific and practical value of the study ... 10
1. LITERATURE REVIEW ... 11
1.1. Epidemiology, Etiology and Clinical Manifestations of Ischemic Heart Disease ... 11
1.2. Psychosocial Stress and Ischemic Heart Disease ... 12
1.2.1. Acute versus Chronic Psychosocial Risk Factors ... 15
1.2.2. Acute Mental Stress ... 16
1.2.3. Anxiety, Depression and Ischemic Heart Disease ... 17
1.3. Psychophysiological Effects of Relaxation ... 19
1.4. The Possibilities of Using Relaxation Techniques for Patients after Myocardial Infarction ... 22
1.5. Mindfulness Body Scan Meditation ... 27
1.6. Progressive Muscle Relaxation ... 31
1.7. The Heart as a Complex System... 32
2. THE DESIGN OF THE STUDY AND METHODS ... 37
2.1. The contingent of subjects... 37
2.2. The object of the study ... 38
2.3. The methods of the study ... 39
2.3.1. Interview ... 39
2.3.3. Electrocardiography ... 40
2.3.4. A method of quantifying heart rhythm coherence ... 41
2.3.5. Measurement of arterial blood pressure ... 42
2.3.6. Mindfulness Body Scan Meditation ... 43
2.3.7. Progressive Muscle Relaxation ... 44
2.4. The protocol of the study ... 44
2.5. Mathematical statistics ... 45
2.6. The model of integral health evaluation ... 47
2.7. The author’s input into this study ... 48
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3. RESULTS ... 49
3.1. The short-term effect of relaxation techniques on cardiovascular system indices ... 49
3.1.1. The short-term effect of relaxation techniques on heart rate and arterial blood pressure ... 49
3.1.2. The short-term effect of relaxation techniques on ECG parameters ... 51
3.2. Correlation of ECG parameters while performing two different relaxation techniques ... 60
3.3. The alternation of variability of ECG parameters during two relaxation techniques ... 63
3.4. The alternation of heart complexity during the relaxation techniques ... 81
3.5. Alternation of cardiovascular indices in patients with and without anxiety during the relaxation techniques ... 83
4. DISCUSSION ... 97
CONCLUSIONS ... 115
PRACTICAL RECOMMENDATIONS AND GUIDELINES FOR FUTURE STUDIES ... 117
REFERENCES ... 118
Published work on the subject of dissertation ... 138
Reports at conferences on the subject of dissertation ... 138
Articles from other published work: ... 138
APPENDICES ... 139
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ABBREVIATIONS ABP – arterial blood pressure
AR – R-wave or heart contraction amplitude
AST – ST amplitude, describing the inner cardiac metabolic system
AT – T-wave amplitude, describing the inner cardiac metabolic system
CAD – coronary artery disease CoPr – complexity profile CVS – cardiovascular system DBP – diastolic blood pressure DJT – duration of JT interval
DQRS – duration of the QRS complex or the spread of excitation in the heart
ECG – electrocardiogram
HF – high frequency band of variability HR – heart rate
HRC – heart rhythm coherence HRV – heart rate variability IHD – ischemic heart disease
JT – interval in ECG from junction point J to T wave end LF – low frequency band of variability
MBSM – Mindfulness Body Scan Meditation MBSR – Midfulness-Based Stress Reduction MI – myocardial infarction
P – Periphery (executive) system PMR – Progressive Muscle Relaxation Post-MI – post-myocardial infarction PTSD – post-traumatic stress disorder QOL – quality of life
R – Regulatory system
r – the Spearman correliation coefficient
RR – time interval between two heart contractions (RR interval) S – Supplying system
SBP – systolic blood pressure
SD – mean standard deviation in the sample
ST – ST segment depression or elevation recorded in electrocardiogram (ST segment amplitude) VLF – very low frequency band of variability
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INTRODUCTION
Ischemic heart disease (IHD) is the leading cause of death in developed countries around the world [251]. Psychosocial factors are now recognized as playing a significant and independent role in the development of IHD and its complications [192]. Mental stress has been implicated as a trigger of myocardial infarction (MI) and sudden death in patients with coronary artery disease [219, 85]. Although anxiety exerts a profoundly negative effect on quality of life (QOL) and adversely influences the outcomes of IHD from many standpoints, including recurrent hospitalization, an increased incidence of ischemic events and higher mortality [108], there has been little investigation of it to date [1].
MI is a major cause of mortality and morbidity in the western world.
Despite a decrease in mortality from MI during the past ten years, many patients suffer adverse emotional reactions subsequent to the heart attack.
As MI is a life threatening event it is hardly surprising that it often causes distress and impairment of QOL for the patients. Cardiac surgery is known to be accompanied by postoperative anxiety [201]. Most patients are clinically anxious on admission to hospital. This anxiety generally remits over the next couple of days but rises again just before discharge, when many patients may again become clinically anxious. This distress is often deliberately hidden from the staff and other patients [231].
Psychological intervention reduces pain, severe anxiety, hostility and depression in these patients and thus improves QOL [221]. The addition of psychosocial treatments to standard cardiacrehabilitation regimens reduces mortality and morbidity, psychological distress, and some biological risk factors [140]. Relaxation therapy is a well-established psychological therapy for alleviating psychological distress in patients with chronic illnesses [73].
Scientists Dixhoorn and White have concluded that relaxation training enhances recovery from an ischemic event, independent of the effect of psycho-education and of exercise [70]. They explained that relaxation therapy can enhance recovery after a cardiac ischemic event and that it encompasses all domains of rehabilitation.
There are many exercises and techniques for achieving relaxation. There are many similarities in the physiological effects of various forms of relaxation technique, but differences have also been observed [69].
Progressive Muscle Relaxation (PMR) is a primary method that is easily learned. Previous studies have shown that PMR has beneficial physiological and psychological effects for various groups of patients. Research has demonstrated that PMR significantly lowers patients' perception of stress,
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and it enhances their perception of health. PMR is beneficial for patients with essential hypertension [64]. Recent research findings also show that PMR training may be an effective therapy for improving psychological health and quality of life in anxious heart patients [207].
Studies of the therapeutic effects of meditation show benefits ranging from reduced cardiovascular risk factors to improved psychological state [117]. Mindfulness Body Scan Meditation (MBSM) is a part of the Mindfulness-Based Stress Reduction (MBSR) program which is a meditation training course developed by Dr. Kabat-Zinn and colleagues at the University of Massachusetts Medical School [94]. “Mindfulness” is defined as moment-to-moment nonjudgmental attention and awareness actively cultivated and developed through meditation [142]. In the USA the use of mindfulness training in treating specific pain conditions, hypertension, myocardial ischemia, weight control, irritable bowel syndrome, insomnia, human immunodeficiency virus (HIV), and substance abuse is presently under investigation in research supported by the National Institutes of Health [94, 142].
In other countries the relaxation techniques are often guided by physical therapists and nurses [38, 8]. Lithuanian scientists have been investigating the relationship between psychoemotional state and other indices in coronary artery disease patients [27, 214, 88, 36]. But there is very little practical application of psychoemotional factor-reducing techniques for ischemic heart disease patients in Lithuanian hospitals. We think it might be because of a common misunderstanding that there is a long period of time needed for achieving the benefits of relaxation. Therefore it is important to research the psychosocial risk factor reducing methods, particularly their short-term effects.
While long-term relaxation therapies improve psychological well-being in heart disease patients, there is little information regarding the short-term effects of relaxation techniques on beat-to-beat dynamics of heart functional indices. We analyzed the ECG parameters in accordance with complex systems theory seeking integrative analysis, which includes interactions between the systems and interactions between their components.
The hypothesis of the study. Relaxation techniques have a significant short-term effect on the functional state of the cardiovascular system in men after myocardial infarction. The short-term effects of Progressive Muscle Relaxation and Mindfulness Body Scan Meditation are expected to differ.
Differences also reflect the individual peculiarities of body complexity.
The aim of the study. To evaluate and compare the functional state of the cardiovascular system in men after myocardial infarction and to explore the peculiarities of its reactions during two relaxation techniques.
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The tasks of the study:
1. To evaluate the short-term effects of relaxation on the functional state of the cardiovascular system.
2. To compare the short-term effects of two relaxation techniques on the functional state of the cardiovascular system.
3. To compare the short-term effects of two relaxation techniques on the functional state of the cardiovascular system given different clinical situations (with anxiety and without).
Novelty, scientific and practical value of the study
The alternation of the cardiovascular system’s functional parameters (except RR interval) during the practice of different relaxation techniques has been studied for the first time in Lithuania.
There was a new relaxation technique applied – Mindfulness Body Scan Meditation. This technique was translated into Lithuanian and audio- recorded. It is simple to use and patients do not require any particular physical or psychological skills. Once permission has been obtained from the Center for Mindfulness at the University of Massachusetts Medical School a CD will be released. It will include a simple explanation, so that anyone can use this relaxation technique easily.
Heart rhythm coherence index has been evaluated for the first time in post-MI patients. The study evaluated the peculiarities of the dynamics of this index during relaxation techniques.
For evaluation of physiological indices the new nonlinear method of analysis – analysis of the second order matrices – was applied. Complexity profiles revealing the peculiarities of the heart as a complex system were designed. Conjunction of the parameters of the different fractal level was investigated.
The scientific and practical value of the study consists in the fact that there is a great need for data that would adequately characterize the functional state during various relaxation techniques in people after MI. In cardiovascular medicine practice there is also a shortage of methods that help patients to reach a relaxation state without increasing arterial blood pressure. Therefore the conclusions made in the study allow one to give more accurate recommendations aimed at individualizing relaxation methods for patients after MI, depending on their anxiety symptoms.
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1. LITERATURE REVIEW
1.1. Epidemiology, Etiology and Clinical Manifestations of Ischemic Heart Disease
Ischemic heart disease (IHD), which is also known as coronary artery disease (CAD), is the leading cause of death in most developed countries, despite decreases in mortality over the last few decades. Although mortality has declined, morbidity has increased, as more patients live with the consequences of ischemic heart damage [63].
Cardiovascular disease claims almost as many lives each year as the next seven leading causes of death combined, and 33% of people who die of heart disease die prematurely (i.e., before their average life expectancy).
Nearly 150,000 people who die of cardiovascular disease each year are under 65 years of age. Mortality with acute infarction is approximately 30%, with more than half of the deaths occurring before the stricken individual reaches the hospital. An additional 5 to 10 percent of survivors die in the first year following myocardial infarction [5].
In the United Kingdom, approximately 2 million people suffer from angina; and the prevalence of CHD in the United States is more than 12 million [63]. According to the data of the Lithuanian Health Information Centre [102], in Lithuania circulatory system diseases (CSD) affect 22.2 percent of adults (over 18 years old). IHD prevalence is of 55.7 per 1000 adults, of which acute and secondary MI is 2.6 per 1000 adults (in the period 2004–2008). In 2008 in Kaunas there were 22,636 people with IHD, of whom 1016 had MI. Of these, the MI morbidity was 2.9 per 1000 adult population (1.4 per 1000 of population 18–64 years of age and 12.4 per 1000 65 years and older).
In Lithuania 33% of the deaths in 2008 were due to IHD. In 2008 standardized mortality rates from CSD for 100,000 adults were 701.4 for men and 400.5 for women. This is significantly more compared to the average of all European countries (547.18 males and 345.87 for women) and to the average of the European Union countries (310.12 males and 203.16 for women) [102].
The pathogenesis of IHD is now known to be atherosclerosis of the epicardial vessels. This process begins early in life, often not clinically manifesting until the middle–aged years and beyond. IHD may present as an acute coronary syndrome, which includes unstable angina, non-ST-segment- elevation myocardial infarction, and ST-segment-elevation myocardial infarction, and MI diagnosed by biomarkers only, chronic stable exertional angina pectoris, and ischemia without clinical symptoms or owing to
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coronary artery vasospasm (variant or Prinzmetal’s angina). Other mani- festations of atherosclerosis include heart failure, arrhythmias, cerebrovas- cular disease (stroke), and peripheral vascular disease [225]. Myocardial ischemia is the result of inadequate myocardial oxygen supply in relation to the demand being placed on the heart and involves inadequate perfusion of cardiac tissue, anaerobic metabolism, diminished or abnormal left ventri- cular contraction, and electrophysiological changes. Ischemia may also cause chest pain [191]. The presence of ischemia is associated with increa- sed risk of adverse cardiac events, independent of coronary anatomy and left ventricular impairment [242].
Thrombotic occlusion of a coronary artery previously narrowed by atherosclerosis leads to MI. Factors such as cigarette smoking, hypertension, and lipid accumulation lead to vascular injury. In the majority of cases, infarction occurs when an atherosclerotic plaque fissures, ruptures, or ulcerates, and, with conditions favoring thrombogenesis (factors which may be local or systemic), a mural thrombus forms leading to coronary artery occlusion. Patients at increased risk of developing acute MI include those with unstable angina, multiple coronary risk factors and Prinzmetal's variant angina. Less common etiologic factors include hypercoagulability, coronary emboli, collagen vascular disease, and cocaine abuse. In roughly one-half of cases no precipitating factor appears to be present. In other cases, triggers such as physical exercise, emotional stress, and medical or surgical illnesses can often be identified [77].
It has long been believed that acute exercise may result in clinical manifestations of CAD [157], but more recent evidence suggests that other behavioral factors, including mental stress, sexual activity, and acute emotions may also trigger coronary events [87, 76, 240]. Research regarding the effects of behavioral factors and triggers on the development and manifestations of cardiovascular disease has thus far largely focused on myocardial ischemia and infarction.
1.2. Psychosocial Stress and Ischemic Heart Disease
A rapidly growing body of evidence supports a relationship between psychosocial factors and cardiovascular disease. Psychosocial stressors can be both a cause and a consequence of cardiovascular disease events [79].
The scientific studies provide clear and convincing evidence that psychosocial factors contribute significantly to the pathogenesis and expression of CAD [193]. This evidence is composed largely of data relating CAD risk to 5 specific psychosocial domains: (1) depression, (2) anxiety, (3) personality factors and character traits, (4) social isolation, and
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(5) chronic life stress. Pathophysiological mechanisms underlying the relationship between these entities and CAD can be divided into behavioral mechanisms, whereby psychosocial conditions contribute to a higher frequency of adverse health behaviors, such as poor diet and smoking, and direct pathophysiological mechanisms, such as neuroendocrine and platelet activation.
In caring for patients with cardiovascular disease, psychosocial factors are an important consideration for several reasons. Buselli and Stuart have identified three areas for discussion in their article [38]. First, the association between psychosocial factors, specifically depression, anxiety, social isolation, anger, hostility, and coronary-prone behavior pattern and increased risk of physiologic arousal as well as morbidity and mortality from cardiovascular disease has been demonstrated in the literature. Second, not treated psychological symptoms have been associated with higher cost, both to the patient and the health care system. In one study, patients who had higher rates of psychological distress in the hospital were more likely to be readmitted to the hospital for a recurrent cardiovascular event within 6 months of discharge when compared with non-distressed patients [3]. In addition, mean re-hospitalization costs were significantly higher ($9,504 versus $2,146) in the distressed patients. Psychosocial factors have been associated with increased risk for non-adherence with recommended lifestyle changes. Depressed, socially isolated, anxious, angry, and pessimistic individuals are less motivated and less able to make the lifestyle changes that are recommended for risk factor modification. Third, humans are unitary beings. The mind and body are connected. To apply the reductionist biomedical model to this chronic illness negates the interaction of mind and body on hemodynamic stability, coronary ischemia, platelet aggregation, lipid metabolism, glucose metabolism, blood pressure, and vasomotor tone as well as emotional well-being, social support, and connection [38].
Many studies have linked stress with negative cardiovascular events [28, 66]. One would have to conclude that the overall data suggests that stress contributes to adverse clinical cardiac events and provides a milieu of increased vulnerability for the heart [68]. Stress is no different from other background cardiac risk factors such as genetics or age. However, stress can be modified through numerous approaches. It remains to be proven if such stress modifications consistently decrease the risk for MI and cardiac death [187]. Diverse and effective stress intervention programs have been tested in heart patients, programs that provide formal psychotherapy, psychotropic medications, time-management training, progressive relaxation training, meditation, or regular exercise. The majority of these intervention programs
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improves patients’ morale and functioning and decrease suffering.
Increasingly, such programs are tracking markers of cardiovascular risk (such as endothelial function) as opposed to cardiac events and find that the psychosocial intervention programs have positive effects [32]. When the stressor continues there are adverse effects on the heart. These stress effects, like other settings of cardiac risk, are potentially modifiable, if not by cardiologists themselves, then by their colleagues who help patients change their behaviors and cognitions [68].
Stress can be a primary or secondary contributor to illness via excessive and sustained sympathetic arousal leading to ischemic heart disease, hypertension, stroke, obesity, and mental ill health, or through related behaviors such as smoking, substance abuse, and over or inappropriate eating [193]; or as a contextual variable in terms of risk factor and lifestyle outcome [192]. In addition, psychosocial stress can impair recovery from any pathological insult or injury. Most assessments of stress relate to life events, and both past and current life stressors, acute and chronic, play a major role. However, beyond the impact of stressors, it is the reported state of feeling stressed that is the critical predictor of illness [166]. Scientists have found that the experience of stress may contribute to the development of clinical manifestations of IHD, irrespective of the presence of conventional risk indicators [166].
When talking about stress after MI, it is important to mention post- traumatic stress disorder (PTSD) – a recognized psychiatric disorder, featuring a triad of symptoms: intrusions (flashback, nightmares); avoidance and emotional numbing (avoidance of reminders of the traumatic event, social withdrawal); and hyperarousal (sleeplessness, exaggerated startle response) [246]. Diagnosis of PTSD requires that a person has been exposed to a traumatic event (in this case, MI), and that his or her response was characterized by intense fear, helplessness or horror, leading to persistence of the above three symptoms for one month or more and causing significant distress or impaired functioning. It has been documented that after MI, patients (ranging from 0% to 22%) are affected by post-MI PTSD [89, 4].
Symptoms indicative of PTSD have been reported by people in the months after acute myocardial infarction (MI) and cardiac surgery [246]. Compared with healthy controls, these patients run a 3-fold risk of having PTSD and more comorbidity such as depression [170] and anxiety [89, 172, 18]. MI patients with PTSD experience higher levels of somatic complaints and poorer social functioning than those who did not develop PTSD [89]. PTSD after MI is associated with poorer general functioning, reduced adherence to drug treatment and increased likelihood of cardiac readmission [89, 205].
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Resent research in Lithuania [34] found that PTSD prevalence among cardiac patients is running at 25% and it manifests equally among patients who have had and have not had heart operations. This study also showed that cardiac patients have high levels of anxiety and depression.
1.2.1. Acute versus Chronic Psychosocial Risk Factors
Psychosocial factors that affect the manifestations of coronary heart disease generally fall into one of three categories: acute stress, chronic environmental factors, and psychological traits [161]. Chronic risk factors are longstanding and influence the development or progression of coronary disease over a period of time (elevated LDL cholesterol, smoking, obesity, hypertension, chronic environmental factors and psychological traits). Acute risk factors are transient pathophysiological changes resulting from external factors, such as physical exercise or acute mental stress. Acute factors do not necessarily contribute to the development of chronic disease, but instead may trigger clinical events, such as myocardial ischemia, myocardial infarction, and sudden death, among individuals who already have CAD.
Acute and chronic psychosocial risk factors are hypothesized to combine to increase the risk of clinical cardiac events. Acute risk factors are often
“triggered” by patient behaviors. Chronic risk factors serve to form a base level of risk, which may decrease the severity of the acute risk factor needed in order to elicit an event. A third category, episodic risk factors, refers to behavioral characteristics, such as depression, that are neither acute nor chronic, but range in duration from several months to several years [126].
According to a model proposed by Muller and colleagues [161], physical and mental activities of the patient may elicit physiological changes that precipitate clinical events. These behaviors are described as “triggers.” The physiological changes they elicit are considered to be acute risk factors for adverse cardiac events. A patient’s behavior may lead to an acute risk factor, such as autonomic changes that lead to reduced heart rate variability. In the presence of vulnerable cardiac substrate, such as myocardial tissue that has been damaged by prior infarction, those autonomic changes could ultimately result in arrhythmia.
Identifying, and subsequently blocking, the acute processes triggering the onset of manifestations of CAD may ultimately reduce the number of cardiac deaths each year [161].
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1.2.2. Acute Mental Stress
Mental stress is one of the possible triggers of cardiac events. Mental stress, defined as a negative state of affect dependent on interpretation or appraisal of threat, harm, or demand is generally accompanied by autonomic arousal, resulting in increased release of glucose into the bloodstream, increased cellular metabolism, and redirection of blood flow from the gastrointestinal tract and kidneys to skeletal muscle [97]. Stress has further been associated with a number of physiological processes that may affect the development or progression of IHD, including hemodynamic, endocrine, and immunologic changes. Stress causes the release of catecholamines and corticosteroids, as well as increases in heart rate, heart contractility, blood pressure, and cardiac output, and decreases in parasympathetic tone [127, 167]. Stress may also result in changes affecting the blood clotting process, such as coronary vasoconstriction, platelet aggregation, increased blood viscosity, or plaque rupture [162, 169, 160]. These physiological changes may increase the incidence of coronary symptoms or adverse outcomes in patients with IHD. Stress-related changes may also contribute to the risk of adverse outcomes and clinical events by promoting the development of atherosclerosis, causing endothelial dysfunction within coronary arteries, triggering arrhythmias, or affecting metabolic risk factors, such as insulin resistance [162, 119, 149].
Laboratory data confirm that acute stress can trigger manifestations of CAD, such as myocardial ischemia, in many individuals with CAD [92, 33].
Recently, laboratory studies utilizing sensitive non-invasive means of measuring ischemia, such as radionuclide ventriculography, positron emission tomography, continuous monitoring of left ventricular function, and two-dimensional echocardiography, have revealed that mental stress can trigger ischemia in a substantial subset of CAD patients [127]. It should be noted that mental stress-induced ischemia typically occurs in patients in whom ischemia is also inducible via physical exercise [127]. Myocardial ischemia induced by mental stress has prognostic value with regard to adverse cardiac outcomes, including mortality. In a study of 126 CAD patients with documented exercise-induced ischemia, those patients who experienced ischemia as a result of mental stress were almost three times more likely to die or to have a cardiac event, such as nonfatal infarction, coronary artery bypass graft surgery, or angioplasty, during the 5-year follow-up period than those patients who had no ischemia in response to mental stress. [110]. Similarly, a follow-up study of 196 CAD patients who underwent mental stress testing as part of the Psychophysiological Investigations of Myocardial Ischemia (PIMI) study revealed that the
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presence of ischemia in response to mental stress predicts subsequent mortality [206].
It has also been determined that stressful experiences can provoke ischemia in CAD patients during their normal daily activities [87, 95].
Gullette and colleagues confirm that high-intensity mental activities increase the risk of ischemia during daily life [95].
1.2.3. Anxiety, Depression and Ischemic Heart Disease
In patients with IHD, anxiety and depression are predictive of adverse short- and long-term outcomes [9, 82, 254]. Patients who have anxiety or depression during hospital admissionare at increased risk for higher rates of in-hospital complications such as recurrent ischemia, re-infarction, and malignant arrhythmias. They also suffer higher mortality and re-infarction rates months to years after their initial cardiac event [82]. Thus, it is important to determine those factors that contribute to patients’
psychological distress and intervene when possible.
Anxiety has been defined as a future-oriented negative affective state resulting from perceptions of threat, characterized by perceived inability to predict, control, or obtains desired results in upcoming situations [10].
Anxiety, a state of uneasiness or apprehension toward a vague or nonspecific threat, is prevalent in cardiac patients [98]. Estimates are as high as 70% to 80% during the acute phase, and it persists long-term in 20% to 25% of patients. Anxiety inflicts its toll through 3 major pathways. In the physiological pathway, anxiety affects the musculoskeletal system by causing muscular tension; the autonomic nervous system by arousing sympathetic responses; and the psychoneuroendocrine system (hypothalamic-pituitary-adrenal axis) by triggering secretion of catecholamines and glucocorticoids. The psychological pathway elevates negative mood states, whereas the social-behavioral pathway promotes disconnection from self and others and stress inhibition with resultant unhealthy lifestyle behaviors. The deleterious effects of this psychophysiological stress response are troublesome because anxiety is an independent predictor of arrhythmic/ischemic complications and increased mortality in cardiac patients [98].
Nurses have evaluated the tools used to assess patients’ anxiety levels to see if they are detrimental to the patients’ psychological state and could activate a stress response. The authors concluded that the use of these instruments was not stressful for stable patients 24 to 48 hours after AMI.
Nurses can therefore be confident that raising the issue of anxiety to patients is not in itself a contributing factor to anxiety level [53].
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The link between anxiety and cardiovascular disease was first explored among individuals with Panic Disorder and other anxiety-related psychopathology [58]. A higher risk of coronary disease has been found among individuals with nonpathological levels of anxiety as well. For example, in a large prospective study of 34,000 men who were initially free of disease, those men who scored highest on an index of phobic anxiety (the Crown Crisp index) were 2.2 times more likely to have fatal myocardial infarctions and 7.7 times more likely to experience sudden death compared to men who scored lowest [122]. Similarly, a 32-year follow-up of 2271 men in the Normative Aging Study yielded similar odds ratios for fatal heart disease and sudden death for those men reporting two or more symptoms of anxiety of the Cornell Medical Index compared to men who reported no symptoms [123].
The scientist Riegel et al. has established that anxiety during the in- hospital phase of acute myocardial infarction is associated with increased risk for in-hospital arrhythmic and ischemic complications that is independent of traditional sociodemographicand clinical risk factors. This relationship is moderated by the level of perceived control such that the combination of highanxiety and low perceived control is associated with the highestrisk of complications [159].
Smith et al. in their study have found that the frequency of ventricular ectopy 12 weeks following MI was associated with daily stress levels and state anxiety, such that patients reporting more stress or greater state anxiety experienced more ectopic beats. These findings underscore the importance of psychological stress during daily life as a risk factor for ventricular ectopy in CHD patients [210].
Although more of an episodic condition than a personality trait, depression has also been associated with the development and progression of IHD [81]. Depression rates are higher among IHD patients than among the general population, especially among post-MI patients. As many as 16- 23% of cardiac patients have Major Depressive Disorder [83], and an additional 30% have depressive symptoms [84]. Depression rates do not appear to increase markedly with severity of cardiovascular disease or increased disability [84]. IHD patients are also more likely to exhibit atypical depressive symptoms than the general psychiatric patients [125].
Among individuals with coronary disease, studies have consistently shown that Major Depressive Disorder affects morbidity and mortality.
Carney and colleagues [48] demonstrated that patients with cardiovascular disease who met the criteria for Major Depression were 2.5 times more likely to develop a serious cardiac complication over the next 12 months than non-depressed patients. Similarly, in a later study, 222 cardiac patients
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were followed after their first myocardial infarction. These patients received structured psychiatric evaluations within 15 days of their heart attack and were followed for 18 months. After controlling for other independent risk factors, Major Depressive Disorder was associated with a 3.5-fold risk of mortality. This risk is comparable to other major risk factors for mortality, such as congestive heart failure and left ventricular function [83, 84].
It appears that the risk of cardiovascular disease associated with depression increases in a linear manner [6, 182] and that depressive symptoms are sufficient to increase risk in the absence of Major Depression [6]. A number of physiological and behavioral mechanisms have been proposed to explain the link between depression and cardiovascular disease.
Depressed individuals are more likely to engage in risk-related behaviors, such as cigarette smoking or lack of physical activity [49]. However, depression is still associated with poor cardiac outcomes, even after statistically controlling for traditional risk factors and risk-related behaviors [90].
About 1 week after discharge many AMI patients experience symptoms of anxiety. Patients showing symptoms of anxiety and depression after discharge following an AMI are at risk for experiencing a persistence of the same symptoms. Assessment and treatment of anxiety and depression, and encouraging lifestyle changes after AMI, continue to be important in post- AMI care that maximizes the outcomes for AMI patients [99]. It has been noticed that the psychosocial risk profile after AMI may be different for male and female patients, and interventions may need to take account of each gender's specific needs [153].
1.3. Psychophysiological Effects of Relaxation
Relaxation is an integrative therapy that can be used as a part of autonomous nursing or physical therapy practice. The beauty of relaxation is that it can be used in any setting, and only a basic set of instructions and a quiet, comfortable environment are needed. The relaxation response, consisting of a mental device, passive attitude, and decreased muscle tone may be evoked through many techniques [98].
In the acute care or critical care setting, many techniques that nurses have traditionally used draw empirical value from the psychophysiological interactions inherent in the mind-body connection [38]. Consider the effect of calming presence, touch, music, massage, and empathic listening in lessening the symptoms of physiological arousal, anxiety, and stress during this critical time. Interventions to decrease physiological arousal are numerous. Demystifying care by inviting the patient to be a partner in his or
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her care and decision-making, providing the patient with choices, allowing unrestricted visiting, providing information, teaching self-management skills, incorporating humor, and promoting therapeutic uninterrupted sleep and rest allows the patient to feel more in control over the environment and situation, which in turn changes perception of threat and thus may reduce anxiety and physiological arousal as well as promote mind-body awareness and connection with others [74, 75].
Relaxation reduces the risk of depression recurrence by 50 percent.
Approximately 10-30% of people will suffer at least one episode of depression in their lives. Relaxation techniques in conjunction with medication reduce the risk of recurrence of depression significantly more than medication alone [143]. Relaxation helps treat anxiety and panic attacks. A study at the University of Massachusetts showed that patients who suffered from generalized anxiety or panic disorder felt significantly better after learning relaxation techniques, and continued to use those techniques over the long-term [114]. Relaxation training can strengthen the immune system. One study showed that after just eight weeks of learning how to relax, participants had a stronger immune system [61].
Many scientists have investigated the effects of relaxation in individuals with certain diseases, most having a cardiovascular disorder, experiencing pain, anxiety, depression etc. [151, 13, 101]. The effect of relaxation training is normalized cardiovascular indices (reduced heart rate, arterial blood pressure), which is especially important in the treatment of hypertension and other cardiovascular diseases, because the cardiovascular system is the first one reacting to stress [214].
Relaxation relieves chronic pain, and relieves chronic low-back pain. In one study, after a ten-week Mindfulness Body Relaxation (MBR) course many patients needed less pain medication. After fifteen months, not only did they suffer less pain, but because they suffered less pain they also suffered less from depression and anxiety [152]. MBR reduces the symptoms of fibromyalgia. In one study, 51 percent of the patients experienced moderate to marked improvement in their fibromyalgia symptoms. That is rare in most treatments of fibromyalgia [120].
Relaxation is defined as a state of relative freedom from anxiety and skeletal muscle tension, that manifests as calmness, peacefulness, and being at ease [145]. In short, relaxation can be defined as psychological and physiological stress reduction [27]. It is intended to bring about a response opposite to the fight-or-flight response. When relaxed, individuals typically exhibit normal blood pressure and decreases in oxygen consumption, respiratory rate, heart rate, and muscle tension [19, 105]. Different relaxation techniques often promote specific psychological and physiolo-
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gical changes, which are also called the relaxation response [27]. There are two basic elements necessary to elicit the relaxation response: (1) focused awareness on a thought, word, phrase, prayer, or repetitive motion; and (2) passive disregard of intruding thoughts [21].
There are certain physiological processes in the body happening while relaxing and breathing slowly and deeply: reduction of the heart rate (HR), respiratory rate, blood pressure and heart variability; decrease in oxygen consumption and carbon dioxide removal [91, 60, 245]; reduction of muscle tension, pain and the electrical conductivity of the skin; return to normal bowel function [150, 39]. Relaxation also increases EEG alpha waves [60, 245], normalizes the levels of thyroid hormone and decreases glucose and cholesterol levels [91]. Relaxation is hypothesized to affect pain by (a) reducing tissue oxygen demand and lowering levels of chemicals such as lactic acid that can trigger pain, (b) releasing skeletal muscle tension and anxiety that can exacerbate pain, and (c) releasing endorphins [145].
Performing relaxing exercises stabilizes the autonomic nervous system and activates the parasympathetic nervous system, which influences the above-mentioned physiological changes in the body [253]. Self-control skills training develops resistance to stress [40], increases stamina, energy level, improves the quality of sleep, strengthens immunity [27]. After the relaxation exercises the body quickly reaches a state of rest. There is a temporary drag of electrophysiological processes in peripheral and central nervous systems during the relaxation that conditions the state which is close to a healthy sleep or meditation [133]. Eliciting the relaxation response, an innate physiological response opposite to the fight-or-flight response, can decrease physiological reactivity as well as symptoms of anxiety, stress, anger, impatience and hostility and can promote openness to different ways of seeing things [21].
Talking about relaxation it is important to mention a new term - heart rhythm coherence (HRC). This term was introduced by The Institute of HeartMath [147], where scientists have found that it is the pattern of the heart’s rhythm that is primarily reflective of the emotional state. HRC is a stable, sine-wave-like pattern in the heart rate variability waveform. The method of evaluating HRC brings a new perspective, focusing on the pattern of the rhythm of heart activity and its relationship to emotional experience.
It is important to differentiate heart coherence from the relaxation effect.
Relaxation is characterized by a higher frequency, lower amplitude rhythm, and a virtually steady heart rate once the system has stabilized in this mode [147]. This happens when the research subjects sit or lie quietly and do not engage in any active cognitive or emotional technique.
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HRC is a highly ordered, smooth, sine-wave-like heart rhythm pattern which is associated with sustained, modulated positive emotions, such as appreciation or love. The scientists found strong differences between quite distinct rhythmic beating patterns that were readily apparent in the heart rhythm trace and that directly matched the subjective experience of different emotions [147]. They have found that changes in the heart rhythm pattern are independent of heart rate: one can have a coherent or incoherent pattern at high or low heart rates. Thus, it is the rhythm, rather than the rate, that is most directly related to emotional dynamics and physiological synchronization. They found that the pattern of the heart’s activity was a valid physiological indicator of emotional experience and that this indicator was reliable when repeated at different times and in different populations.
Coherence is a very beneficial mode which leads to resetting of baroreceptor sensitivity; increased vagal afferent traffic; increased cardiac output in conjunction with increased efficiency in fluid exchange, filtration, and absorption between the capillaries and tissues; increased ability of the cardiovascular system to adapt to circulatory requirements; and increased temporal synchronization of cells throughout the body. This results in increased system-wide energy efficiency and metabolic energy savings [137].
There is typically increased parasympathetic activity during periods of rest or relaxation. Although the coherence mode is also associated with lower heart rate variability, the relaxation techniques which focus attention to the mind, and not on a positive emotion, in general do not induce coherence.
The associated psychological states between relaxation and coherence are also markedly different. The psychological states associated with coherence are directly related to activated positive emotions, whereas other relaxation techniques are essentially disassociation techniques.
1.4. The Possibilities of Using Relaxation Techniques for Patients after Myocardial Infarction
Management of the MI patient may extend beyond the physiological to include psychosocial factors that may adversely affect cardiac health.
Relaxation therapy enhances the physical and psychical outcome of rehabilitation in MI patients [71].
Various interventions including cognitive-behavioral therapies, techniques that elicit the relaxation response, meditation, exercise, and increasing social networks, may play a role in improving health outcomes [38]. A nurse-led experimental trial was conducted to assess the effect of a
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patient-nurse contract on patients’ sense of control and psychological state.
Educational, cognitive, and advisory nursing approaches were associated with reduced distress in men, but being listened to reduced distress in women. Such approaches could significantly improve outcomes in hospitalized patients, although research has shown that critical care nurses do not systematically assess or manage anxiety in patients with acute MI [63].
The goal of psychosocial interventions in the acute phase of an event is to mitigate or prevent symptoms of distress, which has implications across the biological, psychosocial, and spiritual domains. The specific aims of the interventions are fourfold: (1) to decrease physiological arousal; (2) to increase the patient's ability to identify cognitive distortions and realistically appraise stressors; (3) to promote healthy lifestyle habits to enhance coping;
and (4) to promote connection with self, others, and life meaning and purpose. These interventions provide a framework for acquiring self- management skills that are critical for successfully coping with stress, modifying risk factors, and adapting to a chronic illness [38].
Relaxation techniques have long been practiced for various health-related purposes. Interventions such as rhythmic breathing and progressive muscle relaxation (PMR) are basic nursing interventions included in nursing fundamentals textbooks [75]. Unlike the body of work done with patients with heart failure, research by nurses into programs of care that may decrease cardiovascular events, mortality, and hospitalizations has not been adequately developed. Although nursing interventions in acute care (e.g.
monitoring patients for ischemia, reducing anxiety), chronic illness management, and secondary prevention may have significant effects on mortality, morbidity, and costs, few investigators have measured these outcomes and explicated the links between action and outcome [63].
Relaxation reduces the risk of heart disease by 30 %, and reduces deaths due to heart disease by 23 %, according to a study in the American Journal of Cardiology, which also showed that relaxation increases life expectancy [198]. Furthermore it has been known for many years that relaxation techniques significantly reduce the risk of high blood pressure, heart attacks, and fatal heart attacks [168]. Not only does relaxation reduce the risk of heart disease, it actually reverses hardening of the arteries according to a study published in the American Heart Association journal, Stroke [50].
In the acute care setting, techniques to elicit the relaxation response might include guided diaphragmatic breathing; progressive muscle relaxation; visualization; and breath-focused, mindful massage [21]. Patients can be guided in a practice once or twice a day for 10–20 minutes and instructed to use brief minis (stop, take a breath, and release physical and
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mental tension) whenever they feel stressed. During the acute phase, patients do better when guided through the process [38].
After a myocardial infarction or a revascularization procedure attempting to preempt such an event, it has become customary to recommend cardiac rehabilitation to the patient [232]. This process often begins while the patient is under acute care in the hospital [244] and may extend over a period of 6 months to a year after discharge. Cardiac rehabilitation services aim to facilitate physical, psychological and emotional recovery and to enable patients to achieve and maintain better health. This is achieved through exercise, patient education and advice, relaxation, drug therapy, and specific help for patients with psychological sequela [230, 42, 43]. The majority of cardiac rehabilitation programs in the UK are hospital-based combined programs including exercise, psychological and educational interventions [230, 42, 43]. Meta-analyses of the effectiveness of combined programs suggest that they can achieve a reduction in cardiac mortality of 20–26% over a 1–3 year time frame [111].
Stress management is a vital tool in cardiac rehabilitation because of its ability to counteract the physiologically destructive effects of stress [28].
Stress management can take many forms, from group activities designed to foster enhanced social support to psychophysiological interventions such as biofeedback and hypnosis, along with nonstandard approaches such as yoga, meditation, and massage. All of these methods have been found experimentally to have beneficial effects on cardiovascular function and to result in a decrease in morbidity.
Dixhoorn et al. [72] investigated the value of relaxation therapy and exercise training in post-MI patients. The results suggest that a combination of a behavioral treatment such as relaxation therapy with exercise training is more favorable for the long-term outcome after MI than is exercise training alone. Subsequent cardiac events, including death, recurrent infarction, unstable angina, and further bypass grafting occurred in 37% of the exercise-only group compared with just 17% of the combination treatment group. Further investigations indicated that relaxation therapy enhanced the benefits of exercise training for normalizing bradycardia and improving ST segment abnormalities [73]. Although in one study it was concluded that aerobic exercise can be used as a method of stress management itself [80].
Relaxation maneuvers appear to achieve maximal stress-reducing effects when training is provided concurrently with the stressor than when temporally dissociated [55].
There is abundant evidence that different stress reduction techniques alter the activity of the body’s physiological systems [185]. Yet the vast majority of this scientific evidence concerns the effects of negative emotions and
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relaxation [139]. Only a few researchers have begun to investigate the effects of positive emotions: their objective, interrelated physiological and psychological benefits [104, 86]. Although there are many similarities in the physiological effects of various forms of relaxation techniques, differences have also been observed [69]. These differences may suggest that some techniques are better suited to certain clinical populations than others.
Various techniques are used in medicine practice to improve patient’s state of relaxation. Some of the methods are performed alone, and some require the help of another person, often a trained professional; some involve movement, while some focus on stillness; and some methods involve other elements. Certain relaxation techniques known as passive relaxation exercises are generally performed while sitting or lying quietly, with minimal movement. These include autogenic training [218], biofeedback [41], deep breathing and pranayama [57], various meditations [66], progressive Muscle Relaxation [249], visualization [241]. Movement- based relaxation methods incorporate exercise such as walking, yoga, Tai chi [227], Qigong [217], and more.
Some relaxation methods can also be used during other activities, for example, Autosuggestion and Prayer. Music interventions have also been used to reduce anxiety and distress and improve physiological functioning in medical patients. The results of Bradt and Dileo [35] indicated that music listening has a moderate effect on anxiety in patients with CHD: listening to music reduces heart rate, respiratory rate, blood pressure, anxiety and pain in persons with CHD.
One of the most popular relaxation methods is Biofeedback relaxation (BFR). It is the process by which a physiological response is made discernible to the patient; the biological function is transduced into an electrical signal, which can be converted to an audible or a visible display [41]. This information is rendered such that the patient or subject can detect even minute changes in the physiological response, creating an enhanced awareness and a means for the participant to learn to modify the response through operant conditioning. Biofeedback has been used in cardiovascular rehabilitation [31] primarily so that patients could learn to relax via electromyographic activity reduction and cutaneous thermal elevation (indicating peripheral vasodilatation, a relaxation response [78]). Hawkinns, Hart [101] and Barton, Blanchard [13] examined relation between relaxation and pain. These authors state that through BFR people learn to reduce a psychophysiological arousal and gradually change the pain. Khanna et al.
[124] and Kappes [121] worked with two different relaxation techniques.
According to these authors, progressive muscle relaxation (PMR) was more effective in reducing physiological indices such as heart rate, while BFR is
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more effective on psychological parameters as anxiety. Kappes states that both of these relaxation techniques are equally effective in reducing muscle tension and increasing finger temperature [121].
Bieliauskaite, Perminas et al. [27] have investigated physiological effects of applying BFR. The results of the research show that subjective muscle tension decreased during relaxation for the persons who took part in BFR sessions. The physiological tension decreased in the experimental group after four sessions. In the group of BFR were detected statistically significant changes of skin resistance and skin temperature, indicating higher relaxation of respondents [27].
Hypnosis [20, 220] has also been used for intervention in cardiovascular disorders, for the promotion of relaxation, and for assistance with compliance in diet management and smoking cessation. Kroger [130] relates a number of ways in which hypnosis can be helpful in treating cardiovascular disorders and enhancing compliance. Hypnosis-related relaxation can reduce hyperventilation as a stress response, with associated reduction of 1) catecholamine release, 2) tension-related cholesterol elevation, and 3) electrolyte retention, all of which can be beneficial in patients with congestive heart failure. Hypnosis-related relaxation has also been associated with lowering blood pressure, increasing the pain threshold for angina, and reducing the frequency of extrasystoles, especially those associated with sustained anxiety.
Autogenic training was developed by the German psychiatrist Johannes Schultz in 1932. Schultz emphasized parallels to techniques in yoga and meditation. Intensive supervised practice of autogenic training enhances recovery from an ischemic cardiac event and contributes to secondary prevention [70].
There is a growing interest in meditation within the medical community – both in terms of studying its physiological effects and using it with patients [238, 174, 134, 47]. A review of scientific studies identified relaxation, concentration, an altered state of awareness, a suspension of logical thought and the maintenance of a self-observing attitude as the behavioral components of meditation [175]. It is accompanied by a host of biochemical and physical changes in the body that alter metabolism, heart rate, respiration, blood pressure and brain chemistry [134]. Meditation has also been studied specifically for its effects on stress [113, 61]. Overall, there is an extensive literature examining the physiological effects of different forms of meditation. The effects of Transcendental Meditation have been most studied [11, 12, 197, 233]. A lot of other meditative techniques derived from various Asian traditions have been investigated, as well as the physiological correlates of prayer [173, 22, 136, 135, 196, 224, 131]. Lehrer et al.
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observed a significant decrease in respiration rate and a significant increase in heart rate variability associated with respiration (respiratory sinus arrhythmia (RSA)), as well as a general increase in heart rate variability, among Rinzai and Soto Zen practitioners while they were meditating [136].
Rinzai practitioners breathed more slowly before and during meditation.
Bernardi et al. observed similar changes in mantra-based yoga and rosary prayer and an increase in baroreflex sensitivity during these activities [22].
Given the importance of parasympathetic activity (indexed by RSA) an increase in blood-pressure-buffering baroreflex activity might be expected.
Peng et al. observed both similarities and differences in the physiological effects of three forms of meditation, two of which involved specific manipulations of breathing patterns [173]. The one that did not specifically attempt to alter respiration still produced a significant decrease in respiration rate, an increase in RSA, and a decrease in the frequency within the heart rate variability spectrum where RSA was observed. Perhaps most interesting, the authors argue that the pattern of heart rate variability results support the idea meditation involves active, arousal-promoting processes as well as relaxing processes [109].
Dr. Herbert Benson of the Mind-Body Medical Institute, which is affiliated with Harvard and several Boston hospitals, reports that meditation induces a host of biochemical and physical changes in the body collectively referred to as the "relaxation response" [21]. The relaxation response includes changes in metabolism, heart rate, respiration, blood pressure and brain chemistry. Benson and his team have also done clinical studies at Buddhist monasteries in the Himalayan Mountains. Dr. Benson conclusively proved the mind-body connection by showing that simple relaxation techniques could lower people's blood pressure, slow their heart rate, and calm their brain waves.
In the following chapters two other popular relaxation techniques, MBSM and PMR, which have been used in our research, will be described at length.
1.5. Mindfulness Body Scan Meditation
“Mindfulness” is defined as moment-to-moment nonjudgmental attention and awareness, actively cultivated and developed through meditation [142].
The essence of mindfulness is learning to focus one's attention on present- moment experience in a nonjudgmental way. Learning to pay attention to present moment experience offers an alternative to the constant worrying about past and future events, which tends to diminish the quality of one's life [94]. Mindfulness-based interventions aimed at reduction of
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psychological symptoms of distress and enhancement of quality of life, are increasingly applied and popular in various kinds of settings in both mental health care and somatic health care [116]. Several studies have been performed, especially in recent years, which have examined the effects of mindfulness-based stress reduction interventions, mainly in the form of the original Mindfulness-Based Stress Reduction (MBSR) protocol or derivatives thereof [29, 94].
The Mindfulness Body Scan Meditation (MBSM) is a part of the MBSR program which is a meditation training course developed by Dr. Kabat-Zinn and colleagues at the University of Massachusetts Medical School [94]. It is non-religious technique with no requirement for change of lifestyle or adaption to any system of belief.
Individuals such as chronic pain patients may not have the time or ability to fully participate in MBSR programs. Furthermore, it may be difficult to disseminate the beneficial effects of meditation to the general population if it is perceived that meditation’s palliative effect requires an extensive time commitment. Therefore it is interesting and potentially important to examine the physiological effects of different parts of MBSR.
Although MBSR programs have been researched widely, there have been few studies of MBSM on its own. The research findings indicate that a brief 3-day mindfulness meditation intervention is effective at reducing pain ratings and anxiety scores when compared with baseline testing and other cognitive manipulations. The brief meditation training is also effective at increasing mindfulness skills [252]. One study focused on the short-term effects of MBSM [69].It was found that participants displayed significantly greater increases in respiratory sinus arrhythmia while meditating than while engaging in other relaxing activities. A significant decrease in the cardiac pre-ejection period was observed while practicing MBSM. Female participants exhibited a significantly larger decrease in diastolic blood pressure during MBSM than other activities, whereas men had greater increases in cardiac output during MBSM compared to other activities [69].
MBSR teaches participants to notice and relate differently to thoughts and emotions, with a sense of compassion for self and others underlying the endeavor. By continually bringing the mind back to the present moment, mindfulness meditation is thought to increase clarity, calmness, and well- being. This 8-week outpatient program was developed originally for patients with chronic illness and stress-related disorders who had reached the end- point of what modern medicine could offer to relieve their suffering.
Currently both individuals with chronic disease and those who simply want tools to manage stress more effectively participate in this program. During the 8 weeks participants are taught a variety of formal mindfulness
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techniques (such as meditation, yoga and body scanning) which they practice at home using CDs, and the integration of mindfulness into daily living by attending to normal daily tasks which are usually performed mindlessly or automatically. Participants are encouraged to explore their observed experience in both the group and in-between sessions with an attitude of curiosity and kindness, and to investigate how this attitude and attentional stance might, in their immediate experience, be used to ameliorate distress, reduce reactivity, elicit relaxation and enhance skilful responsiveness in the face of challenges.
The duration of the MBSR program was designed by Kabat-Zinn (1982) to be long enough that participants could grasp the principles of self- regulation through mindfulness and develop skill and autonomy in mindfulness practice [117]. The current standard form involves 26 hours of session time consisting of eight weekly classes of 2-1/2 hours each plus an all-day 6-hour class on a weekend day during the sixth week [116]. In its earlier forms the program ranged from 20 to 24 hours of class time; meeting for eight or ten weekly 2-hour sessions and sometimes including the all-day session [112].
The MBSR program focuses on systematic, intensive meditation practice, in combination with other interventions broadly related to contemporary cognitive behavior therapy [115]. Because the concept of meditation within the framework of mindfulness primarily involves the systematic regulation of attention, it is possible to construe virtually any activity or intervention a form of meditation practice. The so-called "formal" meditation encompasses systematic instruction in three practices: the body scan; hatha yoga; and sitting meditation.
The body scan is a guided exercise (30 to 45 minutes) in which attention is systematically directed throughout the body, from one region to another.
It is practiced in a quiet state which promotes (but does not mandate) relaxation. Hatha yoga involves gentle movements taught with moment by- moment attention to encourage greater body awareness and help overcome the "disuse atrophy" (muscle deterioration) so common with advancing age and as a result of illness. Sitting meditation involves developing a capacity for sustained self-observation, in which one learns to direct attention in a systematic manner, initially to a range of specific phenomena, including the breath, sensory stimuli, physical sensations, thoughts, and eventually culminating in an attentive state of "choiceless awareness" which involves simply attending to whatever comes into consciousness without any effort at control [116]. This is one important characteristic of mindfulness meditation that clearly distinguishes it from, for example, the point-centered meditation technique that is at the foundation of Benson's relaxation response [21]. In
