Biomedical subjects

F A Treiber

Publications and source records attributed to F A Treiber.

At least 19 recordsLinked to original sources

PubMed2001

Impact of Transcendental Meditation on cardiovascular function at rest and during acute stress in adolescents with high normal blood pressure.

OBJECTIVE: This study examined the impact of the Transcendental Meditation (TM) program on cardiovascular (CV) reactivity in adolescents with high normal BP. METHOD: Thirty-five adolescents [34 African Americans (AAs), 1 Caucasian American (CA); ages 15-18 years] with resting systolic blood pressure (SBP) between the 85th and 95th percentile for their age and gender on three consecutive occasions, were randomly assigned to either TM (n=17) or health education control (CTL, n=18) groups. The TM group engaged in 15-min meditation twice each day for 2 months including sessions during school lunch break. Primary CV outcome measures were changes in blood pressure (BP), heart rate (HR), and cardiac output (CO) at rest and in response to two laboratory stressors, a simulated car driving stressor and an interpersonal social stressor interview. RESULTS: The TM group exhibited greater decreases in resting SBP (P<.03) from pre- to postintervention, compared to the CTL group. The TM group exhibited greater decreases from pre- to postintervention in SBP, HR, and CO reactivity (P's<.03) to the simulated car driving stressor, and in SBP reactivity (P<.03) to the social stressor interview. CONCLUSION: The TM program appears to have a beneficial impact upon CV functioning at rest and during acute laboratory stress in adolescents at-risk for hypertension.

Adolescent↗

PubMed2001

Cardiovascular (CV) responsivity and recovery to acute stress and future CV functioning in youth with family histories of CV disease: a 4-year longitudinal study.

Blood pressure (BP) and heart rate (HR) data obtained during supine rest, in response to and recovery from four laboratory stressors in a baseline year were used to predict supine resting BP and HR values obtained during each of four consecutive annual follow-up evaluations. Subjects were 385 normotensive youth [95 African American (AA) males, 106 AA females, 92 European American (EA) males, 92 EA females] (mean age 12.7+/-2.6 at baseline year) with a positive family history of cardiovascular disease (CVD). During the baseline evaluation subjects were presented with four laboratory stressors (namely, postural change, video game challenge, social competence interview, and parent--child conflict discussion). The BP and HR values taken during each of the laboratory stressors and during the post stressor recovery periods were converted to z-scores which were averaged to yield aggregate measures for systolic and diastolic BP and HR responsivity and recovery. The data obtained during the baseline evaluation were subsequently used to predict the follow-up values of supine resting BP and HR. The prediction models were fairly consistent across each of the 4 follow-up years. Responsivity or recovery accounted for up to 6% of the total variance after accounting for baseline values. Within the prediction models responsivity or recovery accounted for 4--56% of the variance. The predictive value of the derived models did not decline from one annual evaluation to the next over the length of the study. CV recovery may supplement resting and responsivity in the prediction of future development of CVD

Adolescent↗

PubMed2001

Family history of hypertension and left ventricular mass in youth: possible mediating parameters.

Whether positive family history (FH) of essential hypertension (EH) in normotensive youth is associated with increased left ventricular mass (LVM) and hemodynamic, anthropometric, and demographic parameters previously associated with increased LVM in adults is unknown. To examine these issues, 323 healthy youth (mean age, 13.6 +/- 1.3 years), 194 with positive FH of EH (61% African Americans, 39% whites) and 129 with negative FH of EH (33% African Americans, 67% whites) were evaluated. Hemodynamics were measured at rest and during four stressors (ie, postural change, car driving simulation, video game, forehead cold). Echocardiographic-derived measures of LVM were indexed separately to body surface area and height(2.7). Controlling for age and race differences (ie, 74% of African Americans v 47% of whites had positive FH), the positive FH group exhibited greater LVM/height(2.7), LVM/body surface area, higher systolic (SBP) and diastolic blood pressures (DBP), and total peripheral resistance index (TPRI) and lower cardiac index at rest (P < .05 for all). The positive FH group also displayed higher peak SBP or DBP and higher TPRI increases to each stressor and came from lower socioeconomic status backgrounds (P < .05 for all). Regression analyses indicated that FH of EH was not a significant determinant of LVM/height(2.7) after accounting for contributions of gender (greater in men), general adiposity, resting cardiac index and blood pressure (BP), and TPRI responsivity to video game and cold stimulation (P < .05 for all). Thus, greater LVM index in positive FH of EH youth appears in part related to their greater BP and TPRI at rest and during stress.

Adolescent↗

PubMed2001

Urinary excretion of vasoactive factors are correlated to sodium excretion.

BACKGROUND: The relationship between urinary vasoactive factors and sodium excretion has not been adequately addressed in humans. PROCEDURE: Excretion rates of sodium, nitrates/nitrites (NOx), cGMP, and endothelin-1 (ET-1) were measured before and after ingestion of a mixed electrolyte solution (8 oz Gatorade) while undergoing a routine cardiovascular evaluation in a sample of 51 normotensive young adults. RESULTS: Significant correlations were detected for changes in excretion between all four variables, r ranged from 0.50 to 0.86 (P < .001). Correlations were higher in African Americans than white Americans. CONCLUSIONS: The association of renal ET-1 and NO activity with sodium excretion supports the hypothesis that these factors play a role in the physiologic response to acute changes in sodium intake, particularly in African Americans.

Adolescent↗

PubMed2001

Determination of twin zygosity: a comparison of DNA with various questionnaire indices.

This study examined cross-validation and test-retest reliability of questions and questionnaire indices commonly used for twin zygosity classification. Mothers of 58 monozygotic (MZ) and 52 dizygotic (DZ) same sex twin pairs were interviewed by telephone to answer questions regarding the similarity of their twins (mean age = 14.6 +/- 2.8 years). A logistic regression equation correctly classified 91% of both MZ and DZ twin pairs in our sample using 7 of the 12 zygosity questions. The internal consistency for the total questionnaire (Cronbach's alpha) was 0.88. The median two month temporal stability estimate for the individual questions was r = .56 and r = .79 for the test total. For the cross-validation, zygosity classification indices taken from 9 previous studies were applied to our sample and compared to classification according to DNA microsatellite analyses (agreement range = 44 to 100%). The accuracy of the classification indices was significantly lower than the original studies for 62% of the comparisons. If zygosity determination with DNA markers or blood group typing for all subjects is not feasible, rather than using classification indices based on other studies, an optimal classification scheme can be achieved by using a zygosity questionnaire of which the reliability and validity of the questions is established in a random subsample of the same twin cohort.

Adolescent↗

PubMed2000

The relationship between anger-coping styles and lifestyle behaviors in teenagers.

PURPOSE: To investigate the relationship between anger-coping styles (anger expression and anger suppression) and lifestyle behaviors (physical activity and consumption of alcohol, cigarettes, and caffeine) in adolescents. METHODS: A sample of 411 adolescents (198 males: 101 white, 97 black; 213 females: 101 white, 112 black) aged 13-20 years (mean age 15.6 years) completed the Anger Expression Scale and brief self-report questionnaires assessing physical activity (weekly amount, comparison with peers) and consumption of alcohol (frequency and amount over the past 2 weeks), cigarettes (amount over past 2 weeks), and caffeine (from coffee and soda over past week). RESULTS: Correlational and Chi-square analyses showed teenagers high in anger suppression reported consuming alcohol more frequently, spending fewer hours per week in aerobic activity, and being less physically active than their peers. Teenagers high in anger expression reported consuming more caffeinated soda and coffee. CONCLUSIONS: Results suggest that excessive anger suppression or expression may be associated with an imprudent lifestyle relatively early in life.

Adaptation, Psychological↗

PubMed2000

Cardiovascular reactivity in adolescent boys of low socioeconomic status previously characterized as anxious, disruptive, anxious-disruptive or normal during childhood.

BACKGROUND: The purpose of the study was to compare cardiovascular reactivity, a potential mechanism underlying the development of cardiovascular disease (CVD), in boys with different behavioral characteristics. METHOD: Eighty-nine adolescent boys with low socioeconomic status who were classified as anxious, disruptive, anxious-disruptive or boys without these characteristics (i.e. control) during childhood were observed during a laboratory stress experiment. RESULT: No significant group differences were found for resting levels of diastolic or systolic blood pressure (SBP). Anxious and anxious-disruptive boys exhibited greater SBP reactivity to the social stressor (Social Competence Interview) compared to the disruptive and control boys. The disruptive boys tended to engage in compromising behaviors which are associated with health problems. The anxious boys were significantly more likely to have a positive family history of hypertension. CONCLUSIONS: Boys with different behavioral problems (anxiety, disruptiveness) may be at risk for CVD via different mechanisms.

Adolescent↗

PubMed2000

Racial differences in endothelin-1 at rest and in response to acute stress in adolescent males.

Blacks exhibit greater vasoconstriction-mediated blood pressure (BP) increases in response to stress than do whites. Endothelin-1 (ET-1), a potent vasoconstrictive peptide, has been proposed as having a role in racial differences in stress reactivity. We evaluated the hemodynamic and plasma ET-1 levels of 41 (23 whites, 18 blacks, mean age 18.6 years) normotensive adolescent males at rest and in response to a video game challenge and forehead cold stimulation. Measurements were performed at catheter insertion and before and immediately after the 2 stressors, which were separated by 20-minute rest periods. Blacks exhibited higher absolute levels of diastolic blood pressure, total peripheral resistance index, or both in response to catheter insertion and to the video game challenge and during recovery from video game challenge and cold stimulation (P<0. 05 for all). Blacks exhibited higher absolute levels of ET-1 at every evaluation point (P<0.05 for all) and greater increases in ET-1 in response to both stressors (ps<0.05). These findings suggest that altered endothelial function may be involved in racial differences in hemodynamic reactivity to stress and possibly in the development of essential hypertension.

Acute Disease↗

PubMed2000

Ethnicity and socioeconomic status: impact on cardiovascular activity at rest and during stress in youth with a family history of hypertension.

OBJECTIVE: The purpose of the present study was to examine the potential interaction of ethnicity and SES on hemodynamic functioning at rest and during acute stress in normotensive adolescents with a family history of essential hypertension (EH). DESIGN: The influences of ethnicity and socioeconomic status (SES) on cardiovascular function were evaluated at rest and in response to five different laboratory stressors. METHODS: 110 (50 female) Caucasian and 162 (85 female) African-American normotensive youth (initial age 11.2+/-2.4 years) with a family history of essential hypertension (EH) were tested on two occasions, an average of 2.5 years apart. Based on previous findings, it was predicted that African Americans, particularly those of low SES, would exhibit higher resting blood pressure (BP) and greater cardiovascular reactivity to acute laboratory stressors than would Caucasians. RESULTS: As predicted, African-American youth exhibited higher resting diastolic blood pressure (DBP) and total peripheral resistance (TPR) than Caucasians on both visits (both Ps<.04). African Americans exhibited greater systolic blood pressure (SBP) reactivity than did Caucasians to the video game stressor during both lab visits (both Ps<.02) and greater heart rate reactivity during the first lab visit (P<.01). African Americans exhibited greater SBP and/or DBP, and TPR reactivity to the cold pressor during the first lab visit and the parent-child discussion during the second visit (all Ps<.03). CONCLUSION: As predicted, African Americans exhibited higher resting BP and TPR, and greater cardiovascular reactivity than Caucasians. Although not in the predicted direction, a pattern of interactions began to emerge on the second evaluation. For example, upper SES youth exhibited greater heart rate reactivity compared to all other groups on the social competence interview and parent-child discussion stressors. Further study is needed to clarify the role cardiovascular reactivity may play in the link between ethnicity, SES, and cardiovascular disease risk.

Adolescent↗

PubMed1999

Patterns of body fat deposition in youth and their relation to left ventricular markers of adverse cardiovascular prognosis.

The patterns of body fat deposition in healthy youth and their relation to future development of cardiovascular disease remain incompletely understood. To further evaluate these patterns, we measured indirect indexes of central and general fat deposition in healthy adolescents (mean age 15.4+/-2.3 years) with family histories of hypertension. We examined the relation between these indexes and echocardiographic markers of adverse prognosis as well as the effect of gender and ethnicity. All 225 subjects (64% black and 48% female) had > or =1 biologic parent and 1 grandparent with hypertension. Skinfold thicknesses, waist-to-hip girth ratio, Quetelet index, Ponderal index, conicity, and Z score weight - Z score height were measured. Left ventricular (LV) mass, indexed LV mass, relative wall thickness (RWT), and midwall fractional shortening (MFS) were determined using echocardiography. In both black and white subjects, the adiposity indexes were significantly correlated with posterior wall thickness, total LV mass, and indexed LV mass (p <0.05 for all). Additionally, in black subjects, central adiposity was inversely related to MFS and directly related to RWT and septal thickness. General adiposity independently predicted indexed and nonindexed LV mass, whereas central adiposity predicted MFS and RWT. Compared with subjects with normal LV geometry, those with abnormal geometry were heavier and fatter based on every index of obesity (p <0.03 for all). Thus, indexes of fat deposition are significantly correlated with LV markers of adverse prognosis in healthy youth.

Adolescent↗

PubMed1999

Effects of race, sex, and socioeconomic status upon cardiovascular stress responsivity and recovery in youth.

Cardiovascular (CV) responsivity to and recovery from acute laboratory stressors, as derived from aggregate scores of CV functioning during and after postural change, video game challenge, social competence interview, and parent-child conflict discussion, were evaluated in 272 youths [mean age 13.5 +/- 2.6 years; 162 Blacks (77 males, 85 females), 110 Whites (60 males, 50 females)], all with a positive family history of essential hypertension. Blacks demonstrated greater systolic and diastolic blood pressure (SBP, DBP) and lower heart rate responsivity compared to Whites (all P values < 0.05). A race by neighborhood socioeconomic status (SES) interaction for SBP responsivity was also observed where low SES Whites and high SES Blacks had the greatest responsivity compared to their same race cohorts. Additionally, upper SES Whites had the lowest total peripheral resistance responsivity. For recovery, Blacks and males exhibited higher SBP during recovery compared to Whites and females, respectively. These findings extend previous studies and provide further support for the hypothesis that recovery from stress is a potentially informative component of the contribution of stress responsivity to cardiovascular disease.

Adolescent↗

PubMed1999

Hemodynamic function at rest, during acute stress, and in the field: predictors of cardiac structure and function 2 years later in youth.

Left ventricular hypertrophy is an independent predictor of cardiovascular morbidity and mortality. However, predictors of cardiac structure and function in youth are not completely understood. On 2 occasions (2.3 years apart), we examined 146 youth aged initially 10 to 19 years (mean age, 14.2+/-1.8 years). On the initial visit, hemodynamic function was assessed at rest, during laboratory stress (ie, orthostasis, car-driving simulation, video game, and forehead cold), and in the field (ie, ambulatory blood pressure). Quantitative M-mode echocardiograms were obtained on both visits. On both visits, black compared with white youth had higher resting laboratory systolic blood pressure (P<0.02), greater relative wall thickness (P<0.003), greater left ventricular mass indexed by either body surface area or height(2.7) (P<0.01 for both), and lower midwall fractional shortening ratio (P<0.05). Hierarchical stepwise regression analysis indicated that significant independent predictors of follow-up left ventricular mass/height(2. 7) were the initial evaluation of left ventricular mass/height(2.7), body mass index, gender (males more than females), and supine resting total peripheral resistance (final model R(2)=0.53). Left ventricular mass/body surface area was predicted by initial left ventricular mass/body surface area, weight, gender, mean supine resting total peripheral resistance, and systolic pressure response to car-driving simulation (final model R(2)=0.48). Midwall fractional shortening was predicted by initial midwall fractional shortening, race (white more than black), and lower mean supine total peripheral resistance (final model R(2)=0.13). The clinical significance of these findings and their implications for improved prevention of cardiovascular diseases are yet to be determined.

Adolescent↗

PubMed1999

Assessment of self-reported anger expression in youth.

Internal consistency, temporal stability, and principal components structures of two self-report anger expression scales used in pediatric health research were examined in 415 youth (216 White, 199 Black; 191 boys, 224 girls; mean age 14.7 years). Participants completed the Anger Expression Scale (AXS) and the Pediatric Anger Expression Scale (PAES) on two occasions separated by approximately 1 year. Psychometric properties of the two scales were examined and compared with those reported by the scale authors. For both the AXS and the PAES, estimates of internal consistency (Cronbach s alpha) were acceptable and comparable to values reported by scale authors. Temporal stability of both scales was significant over 1 year. Principal components structures for both scales were similar to those reported by scale authors. Results were generally consistent for age groupings (<13, 13 years), ethnicity, and gender. It is concluded that further research using the AXS and PAES is warranted. The stability of anger expression over time and the assessment of anger suppression is discussed.

Adolescent↗

PubMed1999

Temporal stability of ambulatory blood pressure and heart rate in youths.

BACKGROUND: The use of ambulatory blood pressure monitoring for pediatric populations is increasing. OBJECTIVE: ; To determine the 2-year stability of ambulatory blood pressure in youths. METHODS: We evaluated 2-year stabilities of resting and ambulatory blood pressures in 197 youths (aged 13.9+/-2.3 years at initial evaluation). Readings were taken every 20 min during the daytime (0800-2200 h) and every 30 min at night (0000-0600 h). RESULTS: Daytime and night-time systolic blood pressure increased (P < 0.01 for both) as did resting systolic blood pressure (P < 0.05). Measures of diastolic blood pressure did not change. Changes in systolic blood pressure were related to changes in body size. Estimates of stability for resting and ambulatory measurements were similar, ranging from 0.65 to 0.75. In addition, correlation coefficients for relationships between first and second readings for resting and ambulatory measurements were similar ranging from 0.43 and for resting heart rate to 0.72 for 24h systolic blood pressure (P < 0. 001 for each). The only significant correlation between change scores for resting and ambulatory values was that between resting and night-time diastolic blood pressures (r = 0.33, P < 0.001). CONCLUSION: Measures of blood pressure derived from ambulatory blood pressure monitoring reflect changes in blood pressure in youths at least as well as do changes in resting blood pressure despite the high degree of variability in levels of physical activity and affective states of the children during the ambulatory recordings.

Adolescent↗

PubMed1998

Predictors of future ambulatory blood pressure in youth.

OBJECTIVE: The objective of this study was to determine the predictors of future ambulatory blood pressure in normotensive youths with family histories of essential hypertension. STUDY DESIGN: Eighty-eight healthy youths (mean age 10.9 +/- 2.5 years; 52 blacks, 36 whites; 45 boys) were studied. During an initial visit anthropometric variables and hemodynamics were measured at rest and before, during, and after three laboratory stressors: postural change, forehead cold, and video game challenge. The subjects' ambulatory blood pressure was monitored for 24 hours as part of a follow-up evaluation an average of 2.5 years later. RESULTS: Anthropometric and demographic variables and measures of reactivity to laboratory stressors were related to future daytime and nighttime ambulatory blood pressure. CONCLUSION: These findings provide important information on the predictors of ambulatory blood pressure and underscore the importance of resting blood pressure and adiposity. These results support the guidelines of the Second Task Force, which recommend the measurement of blood pressure and adiposity in the context of ongoing health care.

Blood Pressure↗

PubMed1998

Central adiposity and hemodynamic functioning at rest and during stress in adolescents.

OBJECTIVE: To examine the impact of central adiposity upon hemodynamic functioning at rest and during stress in adolescents. DESIGN: Cross-sectional, correlational study. SUBJECTS: 46 White and 49 Black normotensive adolescents with family histories of essential hypertension. MEASUREMENTS: Systolic and diastolic blood pressure (SBP, DBP), cardiac output and total peripheral resistance responses were assessed at rest, during postural change, video game challenge and forehead cold stimulation. Specific lower and higher waist-to-hip ratio (WHR) tertiles were created for each gender and then integrated for analyses. This resulted in a lower WHR tertile of 11 Whites and 21 Blacks and an upper WHR tertile of 15 Whites and 17 Blacks. RESULTS: No differences in age, gender or ethnicity proportions were found between tertile groups (all P > 0.21). The upper WHR group showed greater body weight, waist and hip circumferences, body mass index (BMI), triceps skinfold and body surface area (all P < 0.001). Controlling for peripheral (that is, triceps skinfold) and overall (that is, BMI) adiposity, the upper WHR group exhibited greater SBP (that is, peak response minus mean pre-stressor level) to all three stressors and greater DBP reactivity to postural change and cold pressor (all P < 0.05). CONCLUSION: Central adiposity appears to adversely influence hemodynamic functioning during adolescence. Underlying mechanisms responsible for these associations require exploration.

Adipose Tissue↗

PubMed1998

Prediction of left ventricular mass in youth with family histories of essential hypertension.

To determine predictors of left ventricular mass (LVM) and hypertrophy (LVH), 56 black and 30 white normotensive healthy youths (mean age 12.6 +/- 2.3 years at initial visit) were studied twice, 2.5 years apart. During the initial visit, anthropometric variables and hemodynamics were measured at rest and before, during, and after 4 physical and behavioral stressors. 2-D directed M-mode echocardiography was performed to derive LVM. Hierarchical multiple regression analyses indicated that follow-up LVM was predicted by initial LVM, weight, height (ht), and gender (males > females; total model R2 = 0.77, P < 0.0001). Predictors of LVM/ht2.7 were initial LVM/ht2.7, weight, ethnicity (blacks > whites), and the aggregate index of blood pressure reactivity (total model R2 = 0.66, P < 0.0001). Youth with LVH at follow-up were taller, heavier, and exhibited greater blood pressure reactivity at initial evaluation. These findings are important since interventional strategies can be developed that target obesity and exaggerated reactivity to stress.

Adolescent↗

PubMed1998

Cardiovascular reactivity and adolescent boys' physical health.

OBJECTIVE: Minor illnesses and major diseases are affected by individual, environmental, and social factors. The purpose of the study was to determine if cardiovascular reactivity, an individual characteristic, was related to adolescent boys' health status and behaviors. METHODS: A total of 89 low socioeconomic status 16-year-old boys who had been classified using teacher ratings during childhood as anxious, disruptive, anxious-disruptive, or normal participated in a laboratory stress experiment. Systolic blood pressure (SBP) and diastolic blood pressure were measured during the Social Competence Interview. Using the upper and lower quartiles of SBP change scores, 21 boys were classified as reactors and 20 boys were classified as nonreactors. Subjects were interviewed to assess health behaviors and outcomes, as well as stressful life events. RESULTS: No significant group differences were found for minor or major physical health problems. A logistic regression analysis indicated that risky health behaviors were associated with SBP reactivity, personality characteristics, and negative life events. Specifically, nonreactors, who were disruptive, had more negative life events and engaged in more health-compromising behaviors (eg, smoking cigarettes, unprotected sex), which may contribute to future health problems (eg, cancer, AIDS). Anxious individuals may be more vulnerable to cardiovascular diseases in part because of exaggerated cardiovascular reactivity to stress. CONCLUSION: Low socioeconomic status boys may be at risk for different health problems caused by differing personality characteristics associated with divergent health-related behaviors.

Adolescent↗