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Mental Stress (mental + stress)
Selected AbstractsThe Effect of Acute Psychological Stress on QT Dispersion in Patients with Coronary Artery DiseasePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2009MUSTAFA HASSAN M.D. Background: An acute psychological stress can precipitate ventricular arrhythmias and sudden cardiac death in patients with coronary artery disease (CAD). However, the physiologic mechanisms by which these effects occur are not entirely clear. Mental stress-induced myocardial ischemia occurs in a significant percentage of the CAD population. It is unknown if the proarrhythmic effects of psychological stress are mediated through the development of myocardial ischemia. Objectives: To examine the effects of psychological stress on QT dispersion (QTd) among CAD patients and whether these effects are mediated via the development of myocardial ischemia. Methods: Psychological stress was induced using a public speaking task. Twelve-lead electrocardiograms (ECG) were recorded at rest, during mental stress, and during recovery. QTd was calculated as the difference between the longest and the shortest QT interval in the 12-lead ECG. Rest-stress myocardial perfusion imaging was also performed to detect mental stress-induced myocardial ischemia. Results: Mental stress induced a significant increase in QTd compared to the resting condition (P < 0.001). This effect persisted beyond the first 10 minutes of recovery (P < 0.001). QTd was significantly associated with the development of mental stress ischemia with ischemic patients having significantly higher QTd during mental stress than nonischemic patients (P = 0.006). This finding remained significant after controlling for possible confounding factors (P = 0.01). Conclusion: An acute psychological stress induces a significant increase in QTd, which persists for more than 10 minutes after the cessation of the stressor. This effect seems to be, at least partially, mediated by the development of mental stress-induced myocardial ischemia. [source] Adrenergic Nervous System Influences on the Induction of Ventricular TachycardiaANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 4 2002Oscar A. Pellizzón M.D. Background: Sudden cardiac death is a major cause of mortality in western countries and the ventricular tachyarrhythmias are mainly involved in this regard. The adrenergic autonomic nervous system has influences in provoking life-threatening arrhythmias, and the prevention of such arrhythmias with beta-blockers supports this viewpoint. To evaluate the effect of the adrenergic nervous system and some catecholamine-releasing stimuli on the induction of ventricular tachycardia, we decided to explore the occurrence of ventricular tachycardia in patients subjected to three consecutive tests, exercise testing, isoproterenol infusion, and mental stress. Methods: Nineteen subjects who experienced exercise test-induced ventricular tachycardia were subjected to an isoproterenol infusion and mental stress. All but one patient had cardiac disease, with 70% due to Chagas'disease. Seventeen of the 19 study subjects had normal ventricular function. Results: Exercise test-induced ventricular tachycardia was nonsustained in 17 patients and sustained in 2 cases. Isoproterenol infusion induced nonsustained ventricular tachycardia in 9 of 19 patients. Mental stress, on its own, was able to induce nonsustained ventricular tachycardia in 2 of 19 patients. Conclusions: Among patients preselected for exercise-induced ventricular tachycardia, almost half could be induced into ventricular tachycardia by isoproterenol infusion. Mental stress was a less powerful inducer of ventricular arrhythmias in this study group. A.N.E. 2002;7(4):281,288 [source] Maladaptation to mental stress mitigated by the adaptive immune system via depletion of naturally occurring regulatory CD4+CD25+ cellsDEVELOPMENTAL NEUROBIOLOGY, Issue 6 2006Hagit Cohen Abstract Peripheral cellular immunity was recently shown to play a critical role in brain plasticity and performance. The antigenic specificity of the participating T cells, however, was not investigated, and nor was their relevance to psychological stress. Here we show, using a mouse model, that adaptive immunity mitigates maladaptation to the acute psychological stress known to trigger abnormal behaviors reminiscent of human post-traumatic stress disorder. Assessment of behavioral adaptation (measured by the acoustic startle response and avoidance behavior) in mice after their exposure to predator odor revealed that maladaptation was several times more prevalent in T cell-deficient mice than in their wild-type counterparts. A single population of T cells reactive to central nervous system (CNS)-associated self-protein was sufficient to endow immune-deficient mice with the ability to withstand the psychological stress. Naturally occurring CD4+CD25+ regulatory T cells were found to suppress this endogenous anti-stress attribute. These findings suggest that T cells specific to abundantly expressed CNS antigens are responsible for brain tissue homeostasis and help the individual to cope with stressful life episodes. They might also point the way to development of immune-based therapies for mental disorders, based either on up-regulation of T cells that partially cross-react with self-antigens or on weakening of the activity of regulatory T cells. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source] Occurrence of seizures in association with work-related stress in young male army recruitsEPILEPSIA, Issue 8 2008Shlomo Moshe Summary Purpose: To examine the risk of undergoing an epileptic seizure as a function of differing levels of occupational stress (physical and mental) in new military recruits with no previous history of epilepsy or with epilepsy in remission for over 2 years. Methods: The medical records of over 300,000 18-year-old men recruited to the Israeli army between mid-eighties and mid-nineties were used to assemble a cohort, which was followed for a period of 30 months. The severity of epilepsy at recruitment was determined according to four categories, 0 (no history of seizures) and 1,3 (history of seizures with different relapse-free periods, with or without treatment). The soldiers were subdivided according to their occupational categories to: combat units (CU), maintenance units (MU), and administrative units (AU). Results: The annual incidence rates per 100,000 in category 0 were 317, 298, and 401 in AU, MU, and CU, respectively. The incidence of seizures in category 0 was higher (relative risk [RR]= 1.29, CI = 1.03,1.62) in CU compared to AU and MU. No differences were found for seizure recurrence among various occupational groups. Conclusion: The increased risk of seizures in CU compared to AU and MU may indicate contribution of service conditions in CU, like physical and mental stress. The equivalent rates of seizure relapse, regardless of the type of occupation, suggests the need for minimal occupational restrictions for epilepsy patients who have been free of seizures for long periods. [source] Exploratory analysis of Chinese-American family caregivers' needs and instructional video on dressing stroke survivorsINTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 5 2010Shu-Hwa LinArticle first published online: 18 AUG 2010 Abstract The aims of this project were to explore the needs of family caregivers in the Chinese-American community and to develop training videos for caregivers on dressing stroke survivors. In-depth, semi-structured, open-ended interviews were used to explore the problems of caregivers of stroke survivors. Forty participants were recruited from Chinese-American communities. Verbatim interview transcripts were coded and analyzed. Four main concerns emerged: the impact and adjustment in lifestyle for family caregivers; lack of social activities and failure to seek community support; physical and mental stress and methods to alleviate stress, such as instruction in heavy lifting and guidance for daily activities, which include dressing. An 18-min video was produced to provide instruction on dressing stroke survivors for those who need this information. Also, this article addresses the lack of social activities and information about community or public services. [source] Stress and the skinINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 4 2006J. Hosoi Synopsis ,The skin is the mirror which reflects the state of the mind.',The skin is the window of the mind.' These have been proverbs since ancient times. It is the topic of this article. Our life became convenient with the information technology these days but too much information often drives us on. We suffer from mental stress rather than physical stress. Since Selye advocated stress reaction, various reactions in the body have been described. Skin is also a target organ of the stress reaction. What the effects of stress are and how stress affects the skin are summarized in this review. Possible use of fragrance for the regulation of the stress reaction is also introduced. Résumé «La peau est le miroir qui reflète l'état de l'esprit»«La peau est une fenêtre sur l'esprit». Ces proverbes sont anciens. Ils sont le thème de cet article. Aujourd'hui, la technologie de l'information rend notre vie commode, mais trop d'informations souvent nous surmènent. Nous souffrons de stress mental plutôt que de stress physique. Depuis la réaction au stress découverte par Selye, de nombreuses réactions du corps ont été décrites. La peau est également un organe cible de la réaction au stress. Cette revue récapitule les effets du stress et comment ce dernier agit sur la peau. L'utilisation potentielle de parfums pour réguler la réaction au stress est également abordée. [source] Psychosocial Correlates of Cardiovascular Reactivity to Anticipation of an Exercise Stress Test Prior to Attending Cardiac Rehabilitation: A Preliminary Test,JOURNAL OF APPLIED BIOBEHAVIORAL RESEARCH, Issue 1 2008Shawn N. Fraser We examined social and psychological correlates of cardiovascular reactivity (CVR), or exaggerated heart rate (HR) and blood pressure (BP) responses to mental stress, in 45 men (mean age = 60.1, SD = 9.9) and 17 women (mean age = 9.9, SD = 11.8) prior to cardiac rehabilitation. HR and BP increased from rest to anticipation, and women had higher resting and preexercise BP. Anxiety was positively related to HR reactivity. HR reactivity was negatively related to self-efficacy in women and positively related to self-efficacy in men. Men and women with more self-efficacy had lower systolic blood pressure (SBP) reactivity, and anxiety was positively related to SBP reactivity in women. Results suggest that the relationship among psychosocial factors and CVR might differ among men and women. [source] Effect of oral melatonin on the procoagulant response to acute psychosocial stress in healthy men: a randomized placebo-controlled studyJOURNAL OF PINEAL RESEARCH, Issue 4 2008Petra H. Wirtz Abstract:, Acute mental stress is a potent trigger of acute coronary syndromes. Catecholamine-induced hypercoagulability with acute stress contributes to thrombus growth after coronary plaque rupture. Melatonin may diminish catecholamine activity. We hypothesized that melatonin mitigates the acute procoagulant stress response and that this effect is accompanied by a decrease in the stress-induced catecholamine surge. Forty-five healthy young men received a single oral dose of either 3 mg melatonin (n = 24) or placebo medication (n = 21). One hour thereafter, they underwent a standardized short-term psychosocial stressor. Plasma levels of clotting factor VII activity (FVII:C), FVIII:C, fibrinogen, D-dimer, and catecholamines were measured at rest, immediately after stress, and 20 min and 60 min post-stress. The integrated change in D-dimer levels from rest to 60 min post-stress differed between medication groups controlling for demographic and metabolic factors (P = 0.047, = 0.195). Compared with the melatonin group, the placebo group showed a greater increase in absolute D-dimer levels from rest to immediately post-stress (P = 0.13; = 0.060) and significant recovery of D-dimer levels from immediately post-stress to 60 min thereafter (P = 0.007; = 0.174). Stress-induced changes in FVII:C, FVIII:C, fibrinogen, and catecholamines did not significantly differ between groups. Oral melatonin attenuated the stress-induced elevation in the sensitive coagulation activation marker D-dimer without affecting catecholamine activity. The finding provides preliminary support for a protective effect of melatonin in reducing the atherothrombotic risk with acute mental stress. [source] Thirty-six-year secular trends in sleep duration and sleep satisfaction, and associations with mental stress and socioeconomic factors , results of the Population Study of Women in Gothenburg, SwedenJOURNAL OF SLEEP RESEARCH, Issue 3 2010ANDISHEH ROWSHAN RAVAN Summary Several European studies have reported sleeping problems in 20,40% of the population. We used data from the Population Study of Women in Gothenburg, based on medical examinations of three different representative cohorts of 38- and 50-year-old women in 1968,1969, 1980,1981 and 2004,2005 to study secular trends in sleep-related factors. The average reported sleep duration declined by about 15 min in the 38-year-old women during the 36 years of observation. No corresponding change in sleep duration was observed among 50-year-old women. During the same period, the proportion of women complaining of sleeping problems almost doubled in both age groups: from 17.7% in 1968 to 31.7% in 2004 in 38-year-old women, and from 21.6% to 41.8% in 50-year-old women. The prevalence of insomnia was higher in 50-year olds than in 38-year olds in all investigated cohorts. The use of sleeping medications remained unchanged since 1968. There were significant associations between perceived sleeping problems and reported lower satisfaction concerning economic, social and family situations, as well as with medical retirement and mental stress. There was, however, no association between alcohol consumption and sleeping problems. Regular leisure time physical activity was not, in most cases, associated with less perceived sleeping problems. Our study indicates that the physician should take socio-economic and family situations into consideration when examining female patients complaining of sleeping problems. Improvements on society level rather than on the individual level could be expected to be more efficient in improving women's sleep. [source] Autonomic skin responses in females with Fabry diseaseJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 3 2009Anette T. Møller Abstract Fabry disease is a genetic lysosomal disorder with dysfunction of the lysosomal enzyme ,-galactosidase A causing accumulation of glycolipids in multiple organs including the nervous system and with neuropathy as a prominent manifestation. Neurological symptoms include pain and autonomic dysfunction. This study examined peripheral autonomic nerve function in 19 female patients with Fabry disease and 19 sex and age-matched controls by measuring (1) sweat production following acetylcholine challenge; (2) the sympathetically mediated vasoconstrictor responses to inspiratory gasp, stress, and the cold pressor test; and (3) cutaneous blood flow following capsaicin. The vasoconstrictor response to inspiratory gasp was increased in Fabry patients compared to controls (p = 0.03), while the response to cold and mental stress did not change. Female patients with Fabry disease had a reduced sweat response to iontophoresis of acetylcholine (p = 0.04) and a smaller capsaicin-induced flare compared to controls. These findings suggest that female patients both have an impaired C-fiber function and local abnormalities in blood vessels and sweat glands. [source] The Effect of Acute Psychological Stress on QT Dispersion in Patients with Coronary Artery DiseasePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2009MUSTAFA HASSAN M.D. Background: An acute psychological stress can precipitate ventricular arrhythmias and sudden cardiac death in patients with coronary artery disease (CAD). However, the physiologic mechanisms by which these effects occur are not entirely clear. Mental stress-induced myocardial ischemia occurs in a significant percentage of the CAD population. It is unknown if the proarrhythmic effects of psychological stress are mediated through the development of myocardial ischemia. Objectives: To examine the effects of psychological stress on QT dispersion (QTd) among CAD patients and whether these effects are mediated via the development of myocardial ischemia. Methods: Psychological stress was induced using a public speaking task. Twelve-lead electrocardiograms (ECG) were recorded at rest, during mental stress, and during recovery. QTd was calculated as the difference between the longest and the shortest QT interval in the 12-lead ECG. Rest-stress myocardial perfusion imaging was also performed to detect mental stress-induced myocardial ischemia. Results: Mental stress induced a significant increase in QTd compared to the resting condition (P < 0.001). This effect persisted beyond the first 10 minutes of recovery (P < 0.001). QTd was significantly associated with the development of mental stress ischemia with ischemic patients having significantly higher QTd during mental stress than nonischemic patients (P = 0.006). This finding remained significant after controlling for possible confounding factors (P = 0.01). Conclusion: An acute psychological stress induces a significant increase in QTd, which persists for more than 10 minutes after the cessation of the stressor. This effect seems to be, at least partially, mediated by the development of mental stress-induced myocardial ischemia. [source] Derangement of Heart Rate Variability During a Catastrophic Earthquake: A Possible Mechanism for Increased Heart AttacksPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 11 2001LIAN-YU LIN LIN, L.-Y., et al.: Derangement of Heart Rate Variability During a Catastrophic Earthquake: A Possible Mechanism for Increased Heart Attacks. At 1:47 AM on September 21, 1999, the middle part of Taiwan was struck by a major earthquake measuring 7.3 on the Richter scale. It has been shown that the mental stress caused by an earthquake could lead to a short- or long-term increase in frequency of cardiac death probably through activation of the sympathetic nervous system. The aim of this study was to investigate the effects of emotional stress on the autonomic system during an actual earthquake. Fifteen patients receiving a 24-hour Holter ECG study starting from 10 ± 4 hours before the onset of the earthquake were included for the analysis of time- and frequency-domains of heart rate variability (HRV) at several time periods. A 24-hour Holter study recorded 2,6 months before the earthquake in 30 age- and sex-matched subjects served as the control group. Heart rate and the low frequency (LF) to high frequency (HF) ratio increased significantly after the earthquake and were attributed mainly to the withdrawal of the high frequency component (parasympathetic activity) of HRV. Sympathetic activation was blunted in elderly subjects > 60 years old. The concomitant ST-T depression observed in the Holter study correlated with a higher increment of LF as compared to HF components. The changes observed in HRV recovered completely 40 minutes following the earthquake. The derangement of HRV results from the withdrawal of the parasympathetic component and the arousal of sympathetic activity by the stressful earthquake. However, this autonomic derangement returned towards normal 40 minutes following the earthquake. [source] Effect of Kava and Valerian on human physiological and psychological responses to mental stress assessed under laboratory conditionsPHYTOTHERAPY RESEARCH, Issue 1 2002M. Cropley Abstract This study investigated whether kava or valerian could moderate the effects of psychological stress induced under laboratory conditions in a group of healthy volunteers. Fifty-four participants performed a standardized colour/word mental stress task on two occasions 1 week apart. Blood pressure (BP), heart rate (HR) and subjective ratings of pressure were assessed at rest and during the mental stress task. Following the first session (time 1,=,T1), individuals took a standard dose of kava (n,=,18), or valerian (n,=,18) for 7 days, while the remainder acted as controls (n,=,18). Differences in BP and HR from resting levels were calculated as reactions to the stress task at both time points. At the second session (time 2,=,T2) there was a significant decrease in systolic BP responsivity in both the kava and valerian groups relative to T1, but there were no significant reductions in diastolic BP. Between T1 and T2, the HR reaction to mental stress was found to decline in the valerian group but not in the kava group. Individuals taking kava or valerian reported less pressure during the task at T2 relative to T1. There were no significant differences in BP, HR or subjective reports of pressure between T1 and T2 in the controls. Behavioural performance on the colour/word task did not change between the groups over the two time points. The results suggest that kava and valerian may be beneficial to health by reducing physiological reactivity during stressful situations. Copyright © 2002 John Wiley & Sons, Ltd. [source] End-of-life care in Italy: personal experience of family caregivers.PSYCHO-ONCOLOGY, Issue 11 2008A content analysis of open questions from the Italian Survey of the Dying of Cancer (ISDOC) Abstract Objective: This study aims at describing the emotional and practical experience of a representative sample of Italian non-professional caregivers when caring for a terminally ill family member and is part of the ,Italian Survey of the Dying of Cancer', which involved 2000 adult cancer deaths representative of the whole country. Methods: Information on patients' experience was gathered from non-professional caregivers by an interview. A specific question was asked about the caregivers' emotional and practical experiences while assisting a terminally ill relative. A content analysis of the open question on caregivers' perceptions was performed on transcribed answers. Three researchers independently generated categories. Subsequently, areas where they differed were reconsidered and an interpretation was agreed upon. Results: Valid interviews were obtained from 1231 non-professional caregivers. Answers were classified according to the perception of the experience as positive (33.1%), negative (65.1%) or neutral (1.8%). Conclusion: Assisting a family member with cancer in his/her last three months of life is a very strong physical and mental stress for the caregiver. In some cases, this experience is nevertheless perceived as an evolution chance. Health-care providers should need to develop programs to ensure that family caregivers' needs for information and support are given great importance. Copyright © 2008 John Wiley & Sons, Ltd. [source] The effects of the spontaneous presence of a spouse/partner and others on cardiovascular reactions to an acute psychological challengePSYCHOPHYSIOLOGY, Issue 6 2006Anna C. Phillips Abstract The presence of supportive others has been associated with attenuated cardiovascular reactivity in the laboratory. The effects of the presence of a spouse and others in a more naturalistic setting have received little attention. Blood pressure and heart rate reactions to mental stress were recorded at home in 1028 married/partnered individuals. For 112 participants, their spouse/partner was present; for 78, at least one other person was present. Women tested with a spouse/partner present showed lower magnitude systolic blood pressure and heart rate reactivity than those tested without. Individuals tested with at least one nonspousal other present also displayed attenuated reactivity. This extends the results of laboratory studies and indicates that the spontaneous presence of others is associated with a reduction in cardiovascular reactivity in an everyday environment; spouse/partner presence would appear to be especially effective for women. [source] Sex differences in the hemodynamic responses to mental stress: Effect of caffeine consumptionPSYCHOPHYSIOLOGY, Issue 4 2006Noha H. Farag Abstract The effect of caffeine on stress responses was compared in 25 men and 22 women in a 2-week placebo-controlled, double-blind, randomized crossover trial. On each week, participants abstained from all dietary sources of caffeine before undergoing a 6-h laboratory protocol under placebo or caffeine exposure followed by a 30-min mental stressor with blood pressure (BP) and cardiovascular hemodynamic assessments. On the placebo session, men and women showed a significant BP increase to stress, although women had significant cardiac responses whereas men had vascular responses. Caffeine ingestion before stress caused both men and women to have enhanced hemodynamic responses to the stressor associated with an increase in cardiac index and a drop in the peripheral resistance index. Caffeine enhances the cardiovascular fight-or-flight response pattern to stress in men and women. [source] Life events and hemodynamic stress reactivity in the middle-aged and elderlyPSYCHOPHYSIOLOGY, Issue 3 2005Douglas Carroll Abstract Recent versions of the reactivity hypothesis, which consider it to be the product of stress exposure and exaggerated hemodynamic reactions to stress that confers cardiovascular disease risk, assume that reactivity is independent of the experience of stressful life events. This assumption was tested in two substantial cohorts, one middle-aged and one elderly. Participants had to indicate from a list of major stressful life events up to six they had experienced in the previous 2 years. They were also asked to rate how disruptive and stressful they were, at the time of occurrence and now. Blood pressure and pulse rate were measured at rest and in response to acute mental stress. Those who rated the events as highly disruptive at the time of exposure and now exhibited blunted systolic blood pressure reactions to acute stress. The present results suggest that acute stress reactivity may not be independent of stressful life events experience. [source] Socioeconomic status and hemodynamic recovery from mental stressPSYCHOPHYSIOLOGY, Issue 2 2003Andrew Steptoe Abstract We assessed the changes in cardiac index and total peripheral resistance underlying blood pressure reactions and recovery from acute mental stress, in relation to socioeconomic status. A sample of 200 men and women aged 47,59 years was divided on the basis of occupation into higher, intermediate, and lower socioeconomic status groups. Blood pressure was monitored using the Portapres, and hemodynamic measures were derived by Modelflow processing of the arterial pressure waveform. Blood pressure increases during two stressful behavioral tasks were sustained by increases in cardiac index and total peripheral resistance. During the 45-min posttask recovery period, cardiac index fell below baseline levels, whereas peripheral resistance remained elevated. Peripheral resistance changes during recovery varied with socioeconomic status and blood pressure stress reactivity, with particularly high levels in reactive low status participants. Results are consistent with the hypothesis that disturbances of stress-related autonomic processes are relevant to the social gradient in cardiovascular disease risk. [source] Comparison of Quantitative T-Wave Alternans Profiles of Healthy Subjects and ICD PatientsANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2009B.Eng., Euler De Vilhena Garcia Ph.D., M.Sc. Background: Current relevance of T-wave alternans is based on its association with electrical disorder and elevated cardiac risk. Quantitative reports would improve understanding on TWA augmentation mechanisms during mental stress or prior to tachyarrhythmias. However, little information is available about quantitative TWA values in clinical populations. This study aims to create and compare TWA profiles of healthy subjects and ICD patients, evaluated on treadmill stress protocols. Methods: Apparently healthy subjects, not in use of any medication were recruited. All eligible ICD patients were capable of performing an attenuated stress test. TWA analysis was performed during a 15-lead treadmill test. The derived comparative profile consisted of TWA amplitude and its associated heart rate, at rest (baseline) and at peak TWA value. Chi-square or Mann-Whitney tests were used with p values , 0.05. Discriminatory performance was evaluated by a binary logistic regression model. Results: 31 healthy subjects (8F, 23M) and 32 ICD patients (10F, 22M) were different on baseline TWA (1 ± 2 ,V; 8 ± 9 ,V; p < 0.001) and peak TWA values (26 ± 13 ,V; 37 ± 20 ,V; p = 0,009) as well as on baseline TWA heart rate (79 ± 10 bpm; 67 ± 15 bpm; p < 0.001) and peak TWA heart rate (118 ± 8 bpm; 90 ± 17 bpm; p < 0.001). The logistic model yielded sensitivity and specificity values of 88.9% and 92.9%, respectively. Conclusions: Healthy subjects and ICD patients have distinct TWA profiles. The new TWA profile representation (in amplitude-heart rate pairs) may help comparison among different research protocols. [source] Adrenergic Nervous System Influences on the Induction of Ventricular TachycardiaANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 4 2002Oscar A. Pellizzón M.D. Background: Sudden cardiac death is a major cause of mortality in western countries and the ventricular tachyarrhythmias are mainly involved in this regard. The adrenergic autonomic nervous system has influences in provoking life-threatening arrhythmias, and the prevention of such arrhythmias with beta-blockers supports this viewpoint. To evaluate the effect of the adrenergic nervous system and some catecholamine-releasing stimuli on the induction of ventricular tachycardia, we decided to explore the occurrence of ventricular tachycardia in patients subjected to three consecutive tests, exercise testing, isoproterenol infusion, and mental stress. Methods: Nineteen subjects who experienced exercise test-induced ventricular tachycardia were subjected to an isoproterenol infusion and mental stress. All but one patient had cardiac disease, with 70% due to Chagas'disease. Seventeen of the 19 study subjects had normal ventricular function. Results: Exercise test-induced ventricular tachycardia was nonsustained in 17 patients and sustained in 2 cases. Isoproterenol infusion induced nonsustained ventricular tachycardia in 9 of 19 patients. Mental stress, on its own, was able to induce nonsustained ventricular tachycardia in 2 of 19 patients. Conclusions: Among patients preselected for exercise-induced ventricular tachycardia, almost half could be induced into ventricular tachycardia by isoproterenol infusion. Mental stress was a less powerful inducer of ventricular arrhythmias in this study group. A.N.E. 2002;7(4):281,288 [source] Immunological effects of stress in psoriasisBRITISH JOURNAL OF DERMATOLOGY, Issue 4 2009G. Schmid-Ott Summary Background, Psychological stress causes phenotypic changes in circulating lymphocytes and is regarded as an important trigger of the Th1-polarized inflammatory skin disease psoriasis. Objective, To study the effects of psychological stress on immunological parameters, i.e. membrane molecules relevant to the pathophysiology of psoriasis, especially cutaneous lymphocyte-associated antigens (CLA) involved in T and natural killer (NK) cells homing in on the skin. Methods, The severity of psoriasis was assessed in patients using the Psoriasis Area and Severity Index. Patients with psoriasis (n = 15) and healthy volunteers (n = 15) were exposed to brief psychological stress in the laboratory. In vitro analyses were conducted 1 h before, immediately following and 1 h after stress exposure. Peripheral T- and NK-cell subsets including CD8+ T lymphocytes, CLA+ lymphocytes and lymphocyte function-associated antigen type 1 (LFA-1)+ lymphocytes were analysed by flow cytometry. Results, We found a significant stress-induced increase of CD3+ T lymphocytes in patients with psoriasis only. Analyses of T-cell subsets revealed that this increase was observable for cytotoxic CD8+ T lymphocytes and CLA+ CD3+ lymphocytes. The total number of circulating NK cells (CD16+, CD56+) increased immediately after stress in both groups whereas only patients with psoriasis showed a significant increase in CLA+ NK cells. Conclusions, A higher stress-induced increase of CLA+ T and CLA+ NK cells in the circulation of patients with psoriasis might point to an increased ability of T and NK cells in the presence of psoriasis to home in on the skin during mental stress. Further studies are needed to verify these relationships in more detail and to investigate the time point at which these cells accumulate within lesional skin, and whether or not psychotherapy improves the quality of life of patients with psoriasis and influences stress-dependent parameters. [source] | |||||||||||||||||||||||||||||||