Am J Physiol Heart Circ Physiol 285: H457-H462, 2003.
First published May 8, 2003; doi:10.1152/ajpheart.00497.2002
0363-6135/03 $5.00
TRANSLATIONAL PHYSIOLOGY
Low arterial compliance in young African-American males
Adrienne S. Zion,1,4
Vernon Bond,5
Richard G. Adams,5
Deborah Williams,5
Robert E. Fullilove,3
Richard P. Sloan,2
Matthew N. Bartels,1
John A. Downey,1 and
Ronald E. De Meersman1,4
Departments of 1Rehabilitation Medicine and
2Psychiatry, 3Mailman School
of Public Health, College of Physicians and Surgeons and
4Teachers College, Columbia University, New York
10032; and 5Department of Medicine, Howard University,
Washington, District of Columbia 20059
Submitted 13 June 2002
; accepted in final form 24 April 2003
 |
ABSTRACT
|
|---|
Hypertension remains a common public health challenge because of its
prevalence and increase in co-morbid cardiovascular diseases. Black males have
disproportionate pathophysiological consequences of hypertension compared with
any other group in the United States. Alterations in arterial wall compliance
and autonomic function often precede the onset of disease. Accordingly, our
purpose was to investigate whether differences exist in arterial compliance
and autonomic function between young, healthy African-American males without
evidence of hypertension and age- and gender-matched non-African-American
males. All procedures were carried out noninvasively following rest. Arterial
compliance was calculated as the integrated area starting at the well-defined
nadir of the incisura of the dicrotic notch to the end of diastole of the
radial artery pulse wave. Power spectral analysis of heart rate and blood
pressure variability provided distributions representative of parasympathetic
and sympathetic modulations and sympathovagal balance. Baroreflex sensitivity
(BRS) was calculated using the sequence method. Thirty-two African-American
and twenty-nine non-African-American males were comparable in anthropometrics
and negative family history of hypertension. t-Tests revealed lower
arterial compliance (5.8 ± 2.4 vs. 8.6 ± 4.0 mmHg · s;
P = 0.0017), parasympathetic modulation (8.9 ± 1.1 vs. 9.7
± 1.1 ln ms2; P = 0.0063), and BRS (13.7 ±
7.3 vs. 21.1 ± 8.5 ms/mmHg; P = 0.0007) and higher
sympathovagal balance (2.9 ± 3.2 vs. 1.5 ± 1.1; P =
0.03) in the African-American group. In summary, differences exist in arterial
compliance and autonomic balance in African-American males. These alterations
may be antecedent markers of disease and valuable in the detection of
degenerative cardiovascular processes in individuals at risk.
arterial hypertension; autonomic nervous system; baroreflex
HYPERTENSION (HT) in African-American males continues to be a
major health challenge because of the staggering financial costs related to
medical and disability expenses. The increased prevalence of morbidity and
mortality due to HT in this group is among the highest in the world
(63). Not only does HT occur
more frequently, but it also presents at an earlier age and causes increased
complications of cardiovascular diseases compared with white Americans
(57). Although the general
prevalence of hypertension has decreased among all genders and ethnic groups
in the United States, recent reports indicate that HT now ranks as the 13th
leading cause of death in the Unites States, having moved up from its former
15th place. A variety of environmental, behavioral, and biological factors
have been proposed to account for the racial differences in the prevalence and
severity of HT.
Arterial HT is associated with structural and functional changes in the
cardiovascular system. These changes involve the conductance in large arteries
as well as the resistance in a small artery
(31). In animal models,
arterial compliance was attenuated in animals with HT compared with a
normotensive group (12).
Specifically, carotid arteries were stiffer due in part to increased smooth
muscle mass (36). In humans,
abnormalities in the diastolic waveform contour, as evidenced by a reduced
area under the dicrotic notch and identified as reduced compliance, have been
recognized in the Framingham and other studies as a possible marker for
cardiovascular morbidity and mortality and in the etiology of arterial
disease, HT (42,
50), stroke
(2,
33,
52), diabetes
(41), and atherosclerosis
(32). Increases in arterial
wall stiffness lead to an augmentation in the stress-strain relationship,
elevating blood pressures and accelerating HT, ultimately inducing
atherosclerosis. Alterations in arterial compliance may precede the onset of
clinically apparent disease and help to identify individuals at risk before
the onset of disease (10,
25). As with arterial wall
compliance, there are conditions in which baroreflex sensitivity (BRS) and
autonomic function are impaired: coronary artery disease, stroke
(2), as demonstrated in the
Framingham study (52),
atherosclerosis, hypertension
(26), diabetes
(4,
20), alcoholic neuropathy
(28), and in smokers
(65). In addition, autonomic
function becomes altered and BRS declines as a natural part of the aging
process (9,
14,
17,
44). Underlying age-related
changes that are thought to alter baroreflex mechanism include arterial
stiffening and a reduced cardiovascular responsiveness to adrenergic
stimulation (38). Strong
evidence, accounting for racial differences in blood pressure, appears to
point toward a decrease in vasodilation during mental and physical stress in
normotensive African-American men, which results in an attenuated buffering of
blood pressure pulsatility
(19,
21).
Therefore, the rationale of this study was to determine whether differences
in arterial compliance and autonomic function exist in young male normotensive
African-Americans with a negative family history of HT compared with a similar
group of non-African-Americans.
 |
METHODS
|
|---|
Thirty-two African-American volunteers were compared with a similar group
of 29 non-African-American males recruited from the staff and student body of
Columbia and Howard Universities. Before enrollment, potential subjects were
screened for general medical history, physical fitness levels, and ancestral
history. Subjects were excluded if they had any systemic medical illness,
allergies that required medications, currently smoked, or had a positive
family history of HT. In accordance with the Institutional Review Boards,
subjects provided written informed consent before being tested. Via
self-report, individuals with two parents or two grandparents of African
descent were assigned to the African-American (AA) group, and those who did
not have any parent or grandparent of African descent were assigned to the
non-African-American (NAA) group.
Subjects arrived at the laboratory between the hours of 7:00 AM and 10:00
AM Tuesday through Friday after an overnight fast. No testing took place on
Mondays, because there may be an exaggerated increase in sympathetic
modulation at the start of the work week compared with other days
(61). Caffeinated products
were not consumed before the testing protocol. After anthropometric
measurements were taken, subjects were instrumented with electrocardiograms
(Max 2000; Marquette Instruments, Marquette, WI), and beat-by-beat radial
blood pressure (BP) (Colin tonometer; Colin, San Antonio, TX) and respiratory
recording (YSI temperature probe; Yellow Springs Instrument, Yellow Springs,
OH) data were captured via an analog-to-digital conversion board (ATMIO-16;
National Instruments, Austin, TX) and stored on a computer. After a 15-min
seated equilibration period in which BP, heart rate, and respiratory rate
fluctuated <5%, 5 min of resting data were acquired in accordance with
published recommendations (60)
and sampled at 500 Hz. As previously mentioned, the area under the diastolic
pressure waveform of the radial artery was utilized to estimate compliance
(37)
(Fig. 1). This method of pulse
wave analysis has been shown to be a valid and reliable method for the early
detection of vascular disease
(10). (For a more detailed
description of the method as well as its shortcomings, the reader is referred
to Ref. 39.) Our laboratory
has used a similar contour analysis method in the past to assess arterial
compliance
(1315).
Specifically, the analysis included two successive 10-beat radial BP waves
that were extracted from the beat-to-beat BP recordings. A well-defined nadir
of the incisura of the dicrotic notch and the end of diastole delineated the
area of integration (37). The
resultant values were averaged and yielded an estimate of arterial compliance.
Power spectral density analysis of heart rate variability (HRV) and blood
pressure variability (BPV) was used to derive measures of autonomic modulation
(55). A priori power spectra
of R-R intervals within the 0.15- to 0.4-Hz range were defined as the
high-frequency (HF) component of HRV (denoted as HFRR),
representing primarily parasympathetic modulation. The low-frequency (LF)
component of HRV (0.040.15 Hz) is a mixture of both parasympathetic
activity and sympathetic activity. Unlike parasympathetic activity, the
sympathetic activity is not easily separated from the power spectrum of HRV
(27). Sympathovagal balance
was computed as the ratio between the LF and HF spectra of HRV
(49). LF BP modulation in the
0.04- to 0.15-Hz range represents sympathetic vasomotor activity
(48,
51). All spectral data were
log transformed to remove skewness and minimize the large standard deviations
customarily present in these data. Digitized R-R intervals and in-phase
systolic peaks determined spontaneous BRS by a modification of the sequence
technique (5), shown to have a
high correlation to invasive methods
(26). After these assessments
were completed, maximum oxygen consumption
(
O2 max) capacity tests
were performed by using open-circuit spirometry (Max 1 metabolic system;
Physiodyne, Farmingdale, NY) according to a standard incremental cycling
protocol (7). Classic criteria
were used to determine whether a maximal effort had been achieved
(7).

View larger version (54K):
[in this window]
[in a new window]
|
Fig. 1. Depiction of the area under the diastolic decay curve
(Ad) of the arterial pressure waveform, used as a measure
of arterial compliance. Pes, end-systolic pressure; Pd,
end-diastolic pressure. [Adapted from Ref.
37.]
|
|
Statistical analyses. Independent t-tests were performed
for all variables pertaining to the hypotheses. As a secondary analysis, a
discriminant analysis was computed based on Fisher's procedures to determine
the relative strength of the arterial compliance, autonomic variables, and BRS
in distinguishing the members of one racial group from another and in
correctly predicting the racial group to which each sample participant
belonged. Data are presented as means ± SD. Probability for all
analyses was set at P < 0.05.
 |
RESULTS
|
|---|
All subjects were American born, listed English as their primary language,
and had no familial history of HT. The AA group consisted of 32 males, and the
NAA group consisted of 29 males. The racial distribution of the NAA group was
55% Caucasian (16/29), 31% Asian (9/29), and 14% Hispanic of non-African
descent (4/29). Descriptive physical characteristics of study subjects by
group are presented in Table 1.
Mean ages, heights, weights, and body mass indexes were similar in both
groups, and there were no differences between groups for
O2 max values, resting
heart rates, systolic BP (SBP), and respiratory rates. Results of arterial
compliance, autonomic modulation, and BRS (t-tests) are presented in
Table 2. The AA group had
significantly lower arterial compliance (5.8 ± 2.4 vs. 8.6 ± 4.0
mmHg · s; P = 0.0017), HFRR (8.9 ± 1.1 vs.
9.7 ± 1.1 ms2; P = 0.0063), and BRS (13.7 ±
7.3 vs. 21.1 ± 8.5 ms/mmHg; P = 0.0007) and a higher LF/HF
ratio (2.9 ± 3.2 vs. 1.5 ± 1.1; P = 0.03) than the NAA
group. The LFRR and LFSBP components (sympathetic
modulation) failed to reach significance
(Table 2). The test of
significance (F value) was used to determine whether the discriminant
function equation was able to predict an independent variable more accurately
than by chance alone. Arterial compliance, HFRR, LFSBP,
LF/HF, and BRS were the variables in the overall model. Probability value was
P < 0.0001. The significance of the univariate F ratio
(7.67) indicated that when the predictors were considered individually, all
except LFSBP modulation significantly differentiated race. The
ANOVA of discriminant scores revealed no within-group differences. The
F ratio for between-group differences was 41.18 (P = 0.00).
Finally, to further assess the accuracy of the analysis, we computed
discriminant scores for each sample participant and compared each
participant's predicted racial group with his actual race. Approximately 77%
of the cases were correctly classified (P < 0.05).
Our major results demonstrate that the AA group had lower arterial
compliance, HFRR (parasympathetic modulation), and BRS and a higher
LF/HF power ratio (sympathovagal balance). Within the discriminant analysis
model, baroreflex sensitivity was the single best predictor of race and was
closely followed by arterial compliance.
 |
DISCUSSION
|
|---|
The results of this new investigation demonstrate that young, normotensive
African-American males have differences in arterial compliance and autonomic
modulation compared with a similar group of non-African-American males. The
loss of arterial compliance has been proposed as a possible mechanism in the
initiation, progression, and etiology of HT and as a prognostic marker of
cardiovascular disease (2).
Once arterial wall degeneration is initiated, a positive feed back loop may be
established whereby degeneration leads to pressure increases, ultimately
leading to further vascular degeneration
(46). In physiological
conditions such as aging or HT, increased wall thickness and luminal diameter
of large arteries reduce vascularity of bodily organs and tissues
(54). As the artery dilates,
wall tension and pulsatile stresses increase and accentuate arterial wall
degeneration that has already occurred. Assessments of large artery stiffness
in HT are complicated by the role of BP in determining values of both pulse
pressure and diameter changes. If the index used does not remove the effects
of intraindividual variation in BP, a residual association with HT is not
unexpected (2). In this
investigation, all subjects for both groups were normotensive and of similar
heights; thus changes in arterial compliance were not dependent on elevations
in BP or height. The method used here to derive arterial compliance measured
the area under the radial artery pressure wave during diastole. We chose the
diastolic phase because nearly two-thirds of the cardiac cycle comprises
diastole, and, as such, any change in compliance during this phase will have a
pronounced effect on overall BP. In addition, and unlike the brachial artery,
the radial artery is a resistance artery composed of smooth muscle and largely
devoid of atherosclerosis. Moreover, because of the group similarities in body
habits,
O2 max, resting
BPs, heart rates, and respiration, we eliminated confounding influences often
present in the measurement of arterial compliance.
Arterial compliance. In the current investigation, the lower
arterial compliance was seen in the presence of an augmentation in
sympathovagal balance. This augmentation has been shown to further reduce
distensibility of small, medium, and large arteries, resulting in a tonic
restraint of elastic and resistance type vessels
(3,
6,
11,
24,
43). Independently and in
combination, the loss of arterial compliance and alterations in autonomic
function are associated with increased HT risk. The age-associated increase in
arterial stiffness manifests as a progressive increase in SBP
(35). Arterial stiffening
(decreased distensibility) leads to changes in the arterial blood pressure
contour (62) and increases in
pulse pressure (47).
Stiffening of the arterial tree has been recognized for more than a century
from clinical and pathological studies as a major risk factor. Although
arterial stiffness was originally regarded as a benign concomitant of the
aging process, it is now acknowledged that additional factors exert
significant influence on arterial stiffness, including ethnic and genetic
differences as well as dietary and activity habits
(62).
BRS. An additional finding of this study was the attenuation in
BRS in the AA group. The baroreceptor response to sustained pressure on the
arterial side of the circulation produces an afferent connection to the
vasomotor and cardioinhibitory areas, and the efferent pathways from these
areas constitute a reflex feedback mechanism that operates to stabilize the BP
and heart rate. When the arterial system is less compliant, this results in a
continuous increased stretch of the baroreceptors, causing a downregulation,
i.e., a loss of sensitivity, in turn altering autonomic function by lowering
parasympathetic modulation and increasing sympathetic outflow. Support for
this attenuation in BRS has been observed in normotensive relatives of
hypertensive patients (18,
59). Furthermore, the loss of
BRS has been shown to be a major risk factor for cardiovascular morbidity and
mortality in postmyocardial infarction patients
(34,
53). We are not aware of any
comparative data of BRS between young, normotensive African-American and
comparable non-African-American males. Moreover, differences in baroreflex
sensitivity here emerged as a significant discriminator between the races.
Parasympathetic modulations. Efferent autonomic signals are
modulated by BRS, which that in turn are tethered to viscoelastic elements in
the arterial walls. Our findings indicate an attenuation of HFRR or
parasympathetic modulation in the AA group compared with the NAA group. The
decrease in parasympathetic activity at rest may be a physiological
consequence of the associated changes in arterial compliance and BRS. We are
aware of the cross-sectional nature of this investigation and therefore are
unable to delineate the temporal sequence of these parameters. However, it is
clear that the loss of parasympathetic modulation is a powerful predictor of
cardiovascular morbidity and mortality in cardiac patients
(34,
53,
56).
Sympathetic modulations. Unlike parasympathetic activity, the
sympathetic activity is not easily separated from the power spectrum of HRV
(27). Therefore, sympathovagal
balance is a better concept used to isolate sympathetic activity that
recognizes both reciprocal and nonreciprocal parasympathetic and sympathetic
influences on heart rate by computing the ratio between the LF and HF spectra
(49). This LF/HF ratio in the
AA group was found to be less favorable compared with the NAA group. An
altered vascular reactivity has been one postulated mechanism for the high
incidence of HT in black men
(1,
29). This may be explained by
genetic differences linked to polymorphic variations in
-adrenergic
receptors having greater peripheral vascular sensitivity to norepinephrine
(22,
40) and/or attenuations in
-adrenergic receptor-mediated vasodilation
(58,
64). Environmental loci
responsible for affecting autonomic balance suggest that the diminished
vascular reactivity exhibited in African-Americans is due to chronic stressors
such as perceived racisms, discriminations, and unfair treatment that lead to
observable differences in physiological function
(8). In addition, reduced
sources of social support in this population are linked to an increased risk
for the development of cardiovascular disease
(16). Our findings demonstrate
a loss of parasympathetic modulation rather than an augmentation of
sympathetic modulation. Regardless of what branch of the autonomic nervous
system has shifted, the outcome leads to a disturbance in sympathovagal
balance, a common denominator in the future development of HT
(29,
30).
This cross-sectional investigation provides for the first time evidence
that arterial wall compliance and autonomic function differ between
African-American and age-matched non-African-American men. The findings in
this cross-sectional investigation may be suggestive that the establishment of
clinical disease may occur much earlier than believed. On the basis of public
health statistics, it is conceivable that these subjects may develop HT at a
future point in their lives. Accordingly, when preclinical markers of disease
risk are verified in young asymptomatic African-Americans, aggressive
behavioral adaptations should be made early to minimize the progression and
onset of cardiovascular disease. As a consequence of early recognition and
effective therapy, hypertensive disease is rarely a problem in the young
(45). The methods to evaluate
arterial compliance and autonomic function utilized in this study were safe,
noninvasive, and caused no discomfort to the subjects. They are relatively
inexpensive and may easily be incorporated into a clinical site physical
examination. Thus preclinical detection can make early interventions possible.
Because health outcomes are shaped by racial inequality
(23), results from this study
could raise awareness toward the initiation of a screening and detection
program using noninvasive assessments to target individuals at risk.
 |
DISCLOSURES
|
|---|
This work was supported by the Vidda Foundation and by National Institutes
of Health Grants HL-61287 and GM-08016.
 |
FOOTNOTES
|
|---|
Address for reprint requests and other correspondence: R. E. De Meersman, 630
West 168th St., Box 38, New York, NY 10032 (E-mail:
red13{at}columbia.edu).
The costs of publication of this article were defrayed in part by the
payment of page charges. The article must therefore be hereby marked
``advertisement'' in accordance with 18 U.S.C. Section 1734 solely to
indicate this fact.
 |
REFERENCES
|
|---|
- Abate N,
Mansour Y, Tuncel M, Arbique D, Chavoshan B, Kizilbash A, Howell-Stampley T,
Vongpatanasin W, and Victor R. Overweight and sympathetic overactivity in
black Americans. Hypertension
38: 379383,
2001.
- Arnett D, Evans
G, and Riley W. Arterial stiffness: a new cardiovascular risk factor?
Am J Epidemiol 140:
669682, 1994.
- Bergel D.
The dynamic elastic properties of the arterial wall. J
Physiol 156:
458469, 1961.
- Bernardi L,
Ricordi L, Lazzari P, Solda P, Calciati A, Ferrari M, Vandea I, Finardi G, and
Fratino P. Impaired circadian modulation of sympathovagal activity in
diabetes. A possible explanation for altered temporal onset of cardiovascular
disease. Circulation 86:
14431452, 1992.
- Bertinieri G,
Di Rienzo M, Cavallazzi A, Ferrari A, Pedotti A, and Mancia G. Evaluation
of baroreceptor reflex by blood pressure monitoring in unanesthetized cats.
Am J Physiol Heart Circ Physiol
254: H1443H1452,
1988.
- Boutouyrie P,
Lacolley P, Girard X, Beck L, Safar M, and Laurent S. Sympathetic
activation decreases medium sized arterial compliance in humans. Am
J Physiol Heart Circ Physiol 267:
H1368H1376, 1994.
- Buchfuhrer M,
Hansen J, Robinson T, Sue D, Wasserman K, and Whipp B. Optimizing the
exercise protocol for cardiopulmonary assessment. J Appl
Physiol 55:
15581564, 1983.
- Clark R.
Perceptions of interethnic group racism predict increased vascular reactivity
to a laboratory challenge in college women. Ann Behav
Med 22:
214222, 2000.
- Cleroux J,
Giannattasio C, Bolla G, Cuspidi C, Grassi G, Mazzola C, Sampieri L, Seravalle
G, Valsecchi M, and Mancia G. Decreased cardiopulmonary reflexes with
aging in normotensive humans. Am J Physiol Heart Circ
Physiol 257:
H961H968, 1989.
- Cohn J,
Finkelstein S, McVeigh G, Morgan D, LeMay L, Robinson J, and Mock J.
Noninvasive pulse wave analysis for the early detection of vascular disease.
Hypertension 26:
503508, 1995.
- Cox R.
Effects of norepinhephrine on mechanics of arteries in vivo. Am J
Physiol 231:
420425, 1976.
- Cox R.
Comparison of arterial wall mechanics in normotensive and spontaneously
hypertensive rats. Am J Physiol Heart Circ Physiol
237: H159H167,
1979.
- De Meersman R. New noninvasive computerized method for the
area measurement of the dicrotic notch. Comput Biol
Med 19:
189195, 1989.
- De Meersman R. Aging as a modulator of respiratory sinus
arrhythmia. J Gerontol 48:
B74B78, 1993.
- De Meersman R,
Zion A, Giardina E, Weir J, Lieberman J, and Downey J. Estrogen
replacement, vascular distensibility and blood pressure trends in
postmenopausal women. Am J Physiol Heart Circ Physiol
274: H863H867,
1998.
- Diez-Roux A,
Stein Merkin S, Arnett D, Chambless L, Mateika J, Nieto F, Sowers J, Szklo M,
Tyroler H, and Watson R. Neighborhood of residence and incidence of
coronary heart disease. N Engl J Med
345: 99106,
2001.
- Ebert T, Morgan
B, Barney J, Denahan T, and Smith J. The effects of aging on baroreflex
regulation of sympathetic activity in humans. Am J Physiol Heart
Circ Physiol 263:
H798H803, 1992.
- Eckberg D.
Carotid baroreflex function in young men with borderline blood pressure
elevation. Circulation 59:
632636, 1979.
- Eichler H,
Blaschke T, and Hoffman B. Decreased responsiveness of superficial hand
veins to phenylephrine in black normotensive males. J Cardiovasc
Pharmacol 16:
177181, 1990.
- Ewing D, Martyn
C, Young R, and Clarke B. The value of cardiovascular autonomic function
tests: 10 years experience in diabetes. Diabetes Care
8: 491498,
1985.
- Falkner B.
Differences in blacks and whites with essential hypertension: biochemistry and
endocrine. Hypertension 15:
681686, 1990.
- Freeman K,
Farrow S, Schmaier A, Freedman R, Schork T, and Lockette W. Genetic
polymorphism of the
2-adrenergic receptor is associated with
increased platelet aggregation, baroreceptor sensitivity, and salt excretion
in normotensive humans. Am J Hypertens
8: 863869,
1995.
- Fullilove M. Comment: abandoning "race" as a
variable in public health researchan idea whose time has come.
Am J Public Health 88:
1297, 1998.
- Gerova M and
Gero J. Range of sympathetic control of the dog femoral artery.
Circ Res 24:
349359, 1969.
- Glasser S,
Arnett D, McVeigh G, Finkelstein S, Bank A, Morgan D, and Cohn J. Vascular
compliance and cardiovascular disease: a risk factor or a marker?
Am J Hypertens 10:
11751189, 1997.
- Goldstein D,
Horowitz D, and Keiser H. Comparison of techniques for measuring
baroreflex sensitivity in man. Circulation
66: 432439,
1982.
- Head G.
Cardiac baroreflexes and hypertension. Clin Exp Pharmacol
Physiol 21:
791802, 1994.
- Johnson R and
Robinson B. Mortality in alcoholics with autonomic neuropathy.
J Neurol Neurosurg Psychiatry
51: 476480,
1988.
- Julius S.
Sympathetic hyperactivity and coronary risk in hypertension.
Hypertension 21:
886893, 1993.
- Julius S, Esler
M, and Randall O. Role of autonomic nervous system in mild hypertension.
Am Heart J 48:
243s252s, 1975.
- Khder Y,
Bray-Desboscos L, Aliot E, and Zannad F. Effects of blood pressure control
on radial artery diameter and compliance in hypertensive patients.
Am J Hypertens 10:
269274, 1997.
- Kingwell B,
Cameron J, Gillies K, Jennings G, and Dart A. Arterial compliance may
influence baroreflex function in athletes and hypertensives. Am J
Physiol Heart Circ Physiol 268:
H411H418, 1995.
- Kannel WB, Wolf
PA, McGee DL, Dawber TR, McNamara P, Castelli WP. Systolic blood pressure,
arterial rigidity, and risk of stroke. The Framingham Study.
JAMA 245:
12251229, 1981.
- La Rovere M,
Bigger J, and Marcus F. Baroreflex sensitivity and heart rate variability
in prediction of total cardiac mortality after myocardial infarction: ATRAMI.
Lancet 351:
478484, 1998.
- Lakatta E,
Mitchell J, Pomerance A, and Rowe G. Human aging changes in structure and
function. J Am Coll Cardiol 10:
42A47A, 1987.
- Levy B. The
mechanical properties of the arterial wall in hypertension.
Prostaglandins Leukot Essent Fatty Acids
54: 3943,
1996.
- Liang Y, Teede
H, Kotsopoulos D, Shiel L, Cameron J, Dart A, and McGrath B. Non-invasive
measurements of arterial structure and function: repeatability,
interrelationships and trial sample size. Clin Sci
(Lond) 95:
669679, 1998.
- Lipsitz L.
Hypotension. In: The Merck Manual of Geriatrics,
edited by Abrams W and Berkour R. Rahway, NJ: Merck, 1990, p.
310325.
- Liu Z, Brinn K,
and Yin FC. Estimation of total arterial compliance: an improved method
and evaluation of current methods. Am J Physiol Heart Circ
Physiol 251:
H588H600, 1986.
- Lockette W,
Ghosh S, MacKenzie S, Baker S, Miles P, Schork A, and Caderet L.
2-Adrenergic receptor gene polymorphism and hypertension in
blacks. Am J Hypertens 8:
390394, 1995.
- McVeigh G,
Brennan G, Hayes R, Cohn J, Finkelstein S, and Johnston D. Vascular
abnormalities in non-insulin-dependent diabetes mellitus identified by
arterial waveform analysis. Am J Med
95: 424430,
1993.
- McVeigh G,
Burns D, Finkelstein S, McDonald K, Mock J, Feske W, Carlyle P, Flack J, Grimm
R, and Cohn J. Reduced vascular compliance as a marker for essential
hypertension. Am J Hypertens 4:
231245, 1991.
- Michel M,
Brodde O, and Insel P. Peripheral adrenergic receptors in hypertension.
Hypertension 16:
107120, 1990.
- Morgan S.
Effects of age on cardiovascular functioning. With an understanding of the
change that occurs in the cardiovascular system, and the risk to adequate
functioning, nurses will be more able to plan interventions.
Geriatr Nurs 14:
249251, 1993.
- Nichols W and
O'Rourke M. Hypertension. In: McDonald's Blood Flow in
Arteries: Theoretical, Experimental and Clinical Principles,
edited by Nichols W and O'Rourke M. London: Oxford Univ. Press,
1998, p. 377395.
- O'Rourke M
(Editor). Arterial Function in Health and Disease.
Edinburgh, UK: Churchill Livingstone, 1982.
- O'Rourke M.
Hypertension. In: Arterial Function in Health and
Disease, edited by O'Rourke M. Edinburgh, UK: 1982,
p. 210224.
- Pagani M,
Lombardi S, Guzetti S, Rimoldi O, Furlan R, Pizzinelli P, Malfatto G,
Dell'Orto S, Piccaluga E, Turiel M, Baselli G, Cerutti S, and Malliani A.
Power spectral analysis of heart rate and arterial pressure variabilities and
a marker of sympatho-vagal interaction in man and conscious dog.
Circ Res 59:
178193, 1986.
- Pagani M,
Lucini D, Pizzinelli P, Bosisio E, Mela G, and Malliani A. Effects of
aging and of chronic obstructive pulmonary disease on RR interval.
J Auton Nerv Syst 59:
125132, 1996.
- Safar ME.
Pulse pressure in essential hypertension: clinical and therapeutical
implications. J Hypertens 7:
769776, 1989.
- Saul J, Berger
R, Albrecht P, Stein S, Chen M, and Cohen R. Transfer function analysis of
the circulation: unique insights into cardiovascular regulation. Am
J Physiol Heart Circ Physiol 261:
H1231H1245, 1991.
- Savage D,
Corwin L, McGee D, Kannel W, and Wolf P. Epidemiologic features of
isolated syncope: The Framingham Study. Stroke
16: 626629,
1985.
- Schwartz P,
Zaza A, Pala M, Locati E, Beria G, and Zanchetti A. Baroreflex sensitivity
and its evolution during the first year after myocardial infarction.
Am J Cardiol 12:
629636, 1988.
- Simon A, Safar
M, Levenson J, London G, Levy B, and Chau N. An evaluation of large
arteries compliance in man. Am J Physiol Heart Circ
Physiol 237:
H550H554, 1979.
- Sloan R, De
Meersman R, Shapiro P, Biagella E, Chernikhova D, Zion A, Paik M, and Myers
M. Blood pressure variability responses to tilt are buffered by cardiac
autonomic control. Am J Physiol Heart Circ Physiol
273: H1427H1431,
1997.
- Smith M,
Ellenbogen K, Eckberg D, Szentpetery S, and Thames M. Subnormal heart
period variability in heart failure: effect of cardiac transplantation.
J Am Coll Cardiol 14:
106111, 1989.
- Stein C, Lang
C, Hong-Guang X, and Wood A. Hypertension in black people: study of
specific genotypes and phenotypes will provide a greater understanding of
inter individual and interethnic variability in blood pressure regulation than
studies based on race. Pharmacogenetics
11: 95110,
2001.
- Svetkey L, Chen
Y, McKeown S, Preis L, and Wilson A. Preliminary evidence of linkage of
salt sensitivity in black Americans at the
2-adrenergic
receptor locus. Hypertension
29: 918922,
1997.
- Takata S, Iwase
N, Okuwa H, Ogawa J, Ikeda T, and Hattori N. Baroreflex function and
pressor responsiveness in normotensive young subjects with a family history of
hypertension. Circulation 49:
990996, 1985.
- Task Force of the European Society of Cardiology
and the North American Society of Pacing and
Electrophysiology. Heart rate variability. Standards of
measurement, physiological interpretation, and clinical use.
Circulation 93:
10431065, 1996.
- Tofler G,
Brezinski D, Schafer A, Czeisler C, Rutherford J, Willich S, Gleason R,
Williams G, and Muller J. Concurrent morning increase in platelet
aggregability and the risk of myocardial infarction and sudden cardiac death.
N Engl J Med 316:
15141518, 1987.
- Vaikevicius P,
Fleg J, Engel J, O'Connor F, Wright J, Lakatta L, Yin F, and Lakatta E.
Effects of age and aerobic capacity on arterial stiffness in healthy adults.
Circulation 88:
14561462, 1993.
- Wali R and Weir
M. Hypertensive cardiovascular disease in African-Americans.
Curr Hypertens Rep 1:
521528, 1999.
- Xie HG, Stein
C, Kim R, Xiao ZS, He N, Zhou HH, Gainer J, Brown N, Haines J, and Wood A.
Frequency of functionally important beta-2 adrenoceptor polymorphisms varies
markedly among African-American, Caucasian and Chinese individuals.
Pharmacogenetics 9:
511516, 1999.
- Zion A, De
Meersman R, Audette J, Downey J, and Lieberman J. Baroreceptor sensitivity
in habitual smokers (Abstract). Clin Auton Res
5: 1995.
This article has been cited by other articles:

|
 |

|
 |
 
J.-B. Choi, S. Hong, R. Nelesen, W. A. Bardwell, L. Natarajan, C. Schubert, and J. E. Dimsdale
Age and Ethnicity Differences in Short-Term Heart-Rate Variability
Psychosom Med,
May 1, 2006;
68(3):
421 - 426.
[Abstract]
[Full Text]
[PDF]
|
 |
|
Copyright © 2003 by the American Physiological Society.