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Biomedical subjects

R H Schneider

Publications and source records attributed to R H Schneider.

17 recordsLinked to original sources
PubMed1997

Effects of the Transcendental Meditation program on adaptive mechanisms: changes in hormone levels and responses to stress after 4 months of practice.

Stress has been implicated in both somatic and mental disorders. The mechanisms by which stress leads to poor health are largely unknown. However, studies in animals suggest that chronic stress causes high basal cortisol and low cortisol response to acute stressors and that such changes may contribute to disease. Previous studies of the Transcendental Meditation (TM) technique as a possible means of countering effects of stress have reported altered levels of several hormones both during the practice and longitudinally after regular practice of this technique. In this prospective, random assignment study, changes in baseline levels and acute responses to laboratory stressors were examined for four hormones-cortisol, growth hormone, thyroid-stimulating hormone and testosterone-before and after 4 months of either the TM technique or a stress education control condition. At pre- and post-test, blood was withdrawn continuously through an indwelling catheter, and plasma or serum samples were frozen for later analysis by radioimmunoassay. The results showed significantly different changes for the two groups, or trends toward significance, for each hormone over the 4 months. In the TM group, but not in the controls, basal cortisol level and average cortisol across the stress session decreased from pre- to post-test. Cortisol responsiveness to stressors, however, increased in the TM group compared to controls. The baselines and/or stress responsiveness for TSH and GH changed in opposite directions for the groups, as did the testosterone baseline. Overall, the cortisol and testosterone results appear to support previous data suggesting that repeated practice of the TM technique reverses effects of chronic stress significant for health. The observed group difference in the change of GH regulation may derive from the cortisol differences, while the TSH results are not related easily to earlier findings on the effects of chronic stress.

Adaptation, Psychological↗
PubMed1997

Anger expression correlates with platelet aggregation.

Potential relationships between increased platelet aggregability and such psychological characteristics as hostility and anger were investigated as part of a larger intervention study investigating the potential efficacy of stress-reduction treatments. Participants performed 6-minute mental arithmetic tests under time pressure. Blood was sampled during the first minute of the task and whole blood platelet aggregation was measured in an aggregometer, using collagen and ADP. To assess anger and hostility, the authors used Spielberger's State-Trait Anger and Anger Expression scales together with the Cook-Medley Hostility Scale. The authors found positive correlations between collagen-induced platelet aggregation and outwardly expressed anger, as measured by the Anger Expression Scale. The findings suggested that modes of anger expression may be associated with increased platelet aggregation. If confirmed by future studies, this finding could provide a mechanism for the putative connection between anger/hostility and coronary heart disease.

Adolescent↗
PubMed1997

A controlled study of the effects of the Transcendental Meditation program on cardiovascular reactivity and ambulatory blood pressure.

Cardiovascular responses to stress reactivity has been proposed as a risk factor for hypertension. In this study, we evaluated the effects of stress reduction on both laboratory cardiovascular reactivity and ambulatory blood pressure in real life on 39 normotensive male subjects who were pretested for ambulatory blood pressure and cardiovascular reactivity to stress using a battery of laboratory stressors. Thereafter, subjects were randomly assigned to practice either the Transcendental Meditation (TM) technique or a cognitive-based stress education control (SEC) for four months. After 4 months, there was no change in cardiovascular response to stressors between the TM and control groups. However, the subjects regularly practicing TM demonstrated a significant reduction of 9 mm Hg (p < .04) in average ambulatory DBP compared to controls. Since ambulatory BP monitoring has been shown to be a better predictor of cardiovascular complications of hypertension than clinic BP, this finding may have important implications for primary prevention of CVD in normotensive subjects.

Adolescent↗
PubMed1996

Usefulness of the transcendental meditation program in the treatment of patients with coronary artery disease.

Twenty-one patients with documented coronary artery disease were tested at baseline by exercise tolerance testing, and assigned to either stress reduction using the Transcendental Meditation (TM) program or to a wait-list control, After 8 months, the TM group had a 14.7% increase in exercise tolerance, an 11.7% increase in maximal workload, an 18% delay in onset of ST-segment depression, and significant reductions in rate-pressure product at 3 and 6 minutes, and at maximal exercise compared with the control group.

Angina Pectoris↗
PubMed1996

Trial of stress reduction for hypertension in older African Americans. II. Sex and risk subgroup analysis.

Our objective was to test the short-term efficacy and feasibility of two stress-reduction approaches for the treatment of hypertension in older African Americans, focusing on subgroup analysis by sex and by high and low risk on six measures of hypertension risk: psychosocial stress, obesity, alcohol use, physical inactivity, dietary sodium-potassium ratio, and a composite measure. The study involved a follow-up subgroup analysis of a 3-month randomized, controlled, single-blind trial conducted in a primary care, inner-city health center. Subjects were 127 African American men and women, aged 55 to 85 years, with diastolic pressure of 90 to 104 mm Hg and systolic pressure less than or equal to 179 mm Hg. Of these, 16 did not complete follow-up blood pressure measurements. Mental and physical stress-reduction approaches-the Transcendental Meditation technique and progressive muscle relaxation, respectively-were compared with a life-style modification education control and with each other. Both systolic and diastolic pressures changed from baseline to follow-up for both sexes and for high and low risk level (defined by median split) on the six measures of hypertension risk. Compared with education control subjects, women practicing the Transcendental Meditation technique showed adjusted declines in systolic (10.4 mm Hg, P < .01) and diastolic (5.9 mm Hg, P < .01) pressures. Men in this treatment group also declined in both systolic (12.7 mm Hg, P < .01) and diastolic (8.1 mm Hg, P < .001) pressures compared with control subjects. Women practicing muscle relaxation did not show a significant decrease compared with control subjects, and men declined significantly in diastolic pressure only (6.2 mm Hg, P < .01). For the measure of psychosocial stress, both the high and low risk subgroups using the Transcendental Meditation technique declined in systolic (high risk, P = .0003; low, P = .06) and diastolic (high risk, P = .001; low, P = .008) pressures compared with control subjects, whereas for muscle relaxation, blood pressure dropped significantly only in the high risk subgroup and only for systolic pressure (P = .03) compared with control subjects. For each of the other five risk measures, Transcendental Meditation subjects in both the high and low risk groups declined significantly in systolic and diastolic pressures compared with control subjects. Effects of stress reduction on blood pressure were found to generalize to both sexes and diverse risk factor subgroups and were significantly greater in the Transcendental Meditation treatment group. These effects (along with high compliance) even in individuals with multiple risk factors for hypertension clearly warrant longer-term investigation in this and other populations.

Aged↗
PubMed1995

A randomised controlled trial of stress reduction for hypertension in older African Americans.

We tested the short-term efficacy and feasibility of two stress education approaches toe the treatment of mild hypertension in older African Americans. This was a randomized, controlled, single-blind trial with 3 months of follow-up in primary care, inner-city health center. Of 213 African American men and women screened, 127 individuals (aged 55 to 85 years with initial diastolic pressure of 90 to 109 mm Hg, systolic pressure of < or = 189 mm Hg, and final baseline blood pressure of < or = 179/104 mm Hg) were selected. Of these, 16 did not complete follow-up blood pressure measurements. Mental and physical stress reduction approaches (Transcendental Meditation and progressive muscle relaxation) were compared with a lifestyle modification education control program and with each other. The primary outcome measures were changes in clinic diastolic and systolic pressures from baseline to final follow-up, measured by blinded observers. The secondary measures were linear blood pressure trends, changes in home blood pressure, and intervention compliance. Adjusted for significant baseline differences and compared with control, Transcendental Meditation reduced systolic pressure by 10.7 mm Hg (P < .0003) and diastolic pressure by 6.4 mm Hg (P <.00005). Progressive muscle relaxation lowered systolic pressure by 4.7 mm Hg (P = 0054) and diastolic pressure by 3.3 mm Hg (P <.02). The reductions in the Transcendental Meditation group were significantly greater than in the progressive muscle relaxation group for both systolic blood pressure (P = .02) and diastolic blood pressure (P = .03). Linear trend analysis confirmed these patterns.(ABSTRACT TRUNCATED AT 250 WORDS)

Black or African American↗
PubMed1990

Beta-adrenergic receptor sensitivity in subjects practicing transcendental meditation.

Several studies suggest that behavioral techniques such as meditation and relaxation may be associated with reduced end organ adrenergic receptor sensitivity. Thus far the evidence supporting this hypothesis has been indirect. We present preliminary findings showing reduced beta-adrenergic receptor sensitivity in a group of subjects practicing Transcendental Meditation. The meditation group (N = 10), compared to controls (N = 10), had a lower percentage of functional lymphocyte beta-adrenergic receptors (p = 0.009), but showed no difference in total receptor number or plasma catecholamines. There were no differences between the groups in Type A behavior, the Type A components, exercise, or family history of hypertension. The results provide some support for studies postulating that meditation is associated with reduced sympathetic adrenergic receptor sensitivity, and provide encouragement for the efficacy of receptor measurement in psychophysiology research.

Adult↗
PubMed1989

Anger assessment and reactivity to stress.

This study compared a questionnaire method to an interview method of anger assessment in predicting reactivity to a stressor and explored possible associations between anger expression and reactivity to a stressor. Blood pressure, heart rate and plasma catecholamines were measured in 40 normotensive subjects before and after a 5 min mental arithmetic task. The questionnaire and interview anger scores were related (p = 0.03). Anger expressed outward was associated with lower heart rate (p = 0.005) and norepinephrine (p = 0.01) reactivity to the stressor. The results suggest that self report questionnaires may be a reliable and inexpensive way to evaluate anger in the context of reactivity to stressors and that anger expression, particularly anger expressed outward, may be related to decreased heart rate and norepinephrine reactivity. The relationship between anger expression and reactivity to stressors may provide insight into the mechanisms linking anger, blood pressure and incidence of cardiovascular disease.

Adult↗
PubMed1985

Methods for measuring vascular and nonvascular alpha-receptor sensitivity in humans.

Since increased alpha-adrenergic reactivity may participate in the pathophysiology of essential hypertension, methods for accurately assessing in vivo alpha-receptor sensitivity in humans might be useful. The goals of this study were to employ previously used methods, namely pupillometry and local forearm intraarterial infusions, to assess alpha-receptor sensitivity, create an in vivo environment of decreased sympathetic drive (plasma norepinephrine) and increased alpha-receptor number (platelet alpha 2), in which increased alpha-receptor sensitivity to exogenous agonists might occur. Five patients with minimally elevated blood pressure (139 +/- 5/90 +/- 4 mm Hg) while on diuretic monotherapy completed assessment of biochemical and physiologic variables on diuretic alone and again on diuretic and guanadrel. Guanadrel plus diuretic compared with diuretic alone lowered the seated diastolic and standing systolic and diastolic blood pressure. Heart rate was decreased about 10 beats/min. Baseline supine norepinephrine was reduced an average of 40% (from 281 +/- 23 to 168 +/- 16 pg/ml, p = 0.03), and platelet alpha 2-receptors were increased roughly 40% (from 178 +/- 34 to 250 +/- 54 fmol/micrograms, p = 0.07). Despite the expected decrease in sympathetic drive and increase in alpha-receptors (platelet alpha 2), the pupillary mydriatic response to phenylephrine and the forearm vasoconstrictor response to intraarterial norepinephrine were not augmented. The failure to detect increased physiologic responsiveness in the presence of decreased norepinephrine and increased alpha 2-receptor number lends itself to multiple explanations which need to be tested in future research.(ABSTRACT TRUNCATED AT 250 WORDS)

Arm↗
PubMedDate not supplied

Anger and anxiety in borderline hypertension.

Psychologic studies of hypertension have usually focused on the relationship of anger and anxiety to clinic or laboratory blood pressure (BP). Yet, average blood pressure outside of the clinic has proven to be a more important predictor of hypertensive complications. In this study, we have isolated two groups of borderline hypertensives--one group that maintained high blood pressure outside of the clinic and another whose average BP returned to normal at home. All 33 subjects were given psychometric instruments for measuring various components of anger and anxiety: Spielberger's State-Trait Personality Inventory, the Anger Expression Scale, and the State Anger Reaction Scale. The high home BP group reported greater intensity of anger, although they suppressed their expression of anger to a greater extent. The groups did not differ in anxiety. Also, blood pressure variability was not different between the two groups. It is suggested that the psychologic differences found in the group of higher-risk borderline hypertensives may, through autonomic arousal, contribute to the later development of established hypertension.

Adult↗
PubMedDate not supplied

New markers for type A behavior: pupil size and platelet epinephrine.

This study tested the hypothesis that the Type A behavior pattern and its components are associated with increased activity of the sympathetic nervous system. To do this, we employed two new markers of sympathetic tone--pupil size and platelet catecholamine content. Thirty-three healthy males were blindly rated for Type A behavior and verbal stylistic components by Structured Interview. Adrenergic tone to the pupils was assessed from pupil diameter recorded by infrared television pupillometry, and pupil alpha-adrenergic sensitivity was estimated from mydriatic response to ophthalmic phenylephrine. Platelet epinephrine and norepinephrine contents were assayed because these levels are associated with chronic, long-term circulating catecholamine levels. The results showed Type As had consistently larger pupil diameters than Type Bs (p = 0.03, 0.03, and 0.01). There was no difference in pupillary response to phenylephrine instillation between groups. Platelet epinephrine content was greater in Type A subjects (chi 2 = 4.25, p less than 0.04, t = 1.6, p = 0.06). Only the component of explosiveness was modestly associated with resting pupil size, and no components significantly predicted platelet catecholamines. We conclude that the results of these two new markers of autonomic activity, namely, pupil size and platelet epinephrine, suggest that Type A behavior is characterized by increased sympathetic nervous system tone although we cannot rule out the possibility of decreased activity of the parasympathetic nervous system.

Adult↗
PubMedDate not supplied

Ambulatory blood pressure monitoring and laboratory reactivity in type A behavior and components.

Type A coronary-prone behavior has been characterized previously by cardiovascular hyperreactivity to laboratory stressors. The objectives of this study were: 1) to determine whether cardiovascular patterns under more naturalistic circumstances in the field were altered in Type A subjects, and 2) to determine whether these field patterns paralleled cardiovascular patterns to a series of stressors in the laboratory. Thirty-three healthy Type A and B men underwent 24-hr ambulatory blood pressure and heart rate monitoring during a normal day of activities. These subjects were also tested in the laboratory for blood pressure and heart rate responses to a series of stressor tasks: 1) cognitive (mental arithmetic), 2) perceptual motor (reaction time), and 3) physical (handgrip). Type A behavior and stylistic components were rated by structured interview. All studies were conducted double blindly. Type A subjects demonstrated greater cardiovascular reactivity to the laboratory cognitive stressor, but there was a mixture of differences between As and Bs in variability of ambulatory blood pressure and heart rate during different periods of the day. Yet, there were no differences in average blood pressure levels. The components of verbal competition and loudness of voice were positively associated with elevated average blood pressure and variability in the field, respectively, but not with laboratory hyperreactivity. Thus, this study confirmed laboratory-induced cardiovascular hyperreactivity in Type A behavior but, within its limitations, did not find a similarity between laboratory and field cardiovascular response patterns in these behavioral groups. The ambulatory blood pressure monitoring findings in the component groups may have prognostic significance and deserve further study.

Adult↗
PubMedDate not supplied

Lower lipid peroxide levels in practitioners of the Transcendental Meditation program.

OBJECTIVE: Oxidative stress or free radical activity may contribute to the pathophysiology of atherosclerosis and other chronic diseases associated with aging. Because psychosocial stress has been shown to increase oxidative stress, we conducted an exploratory study to investigate the effects of stress reduction with the Transcendental Meditation program on serum lipid peroxide levels in elderly subjects. METHOD: Forty-one normally healthy subjects (aged 56 to 74 years, average 67 years) were recruited from the same Midwest city. Eighteen were long-term practitioners of the TM program (average 16.5 years). Twenty-three controls were not practicing a formal stress management technique. Venous blood samples were analyzed for lipid peroxides by the TBARS assay. A dietary questionnaire was used to assess fat intake, red meat consumption, antioxidant vitamin supplementation, and smoking. Differences between groups and subgroups were analyzed by t test, and correlations. RESULTS: Significantly lower serum levels of lipid peroxides were found in the TM practitioners compared with controls (-15%, p = .026). No significant differences were found between groups on smoking, fat intake, or vitamin supplementation. TM practitioners also had lower red meat consumption but matched subgroup analysis and partial correlations did not confirm a relationship between red meat intake and lipid peroxide levels. CONCLUSIONS: These preliminary findings suggest that lower serum lipid peroxide levels may be associated with stress reduction using the Transcendental Meditation technique. Prospective controlled trials are needed to confirm that this effect is because of TM practice rather than other lifestyle factors, such as diet.

Aged↗