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Acta Cardiol Sin 2008;24:35-8
Pediatric Cardiology
Reference Values of Brachial-Ankle
Pulse Wave Velocity in Children
Chin-Fu Wang,1 Yu-Tsun Su1 and Kai-Sheng Hsieh2
Background: Arterial wall properties are important parameters reflecting the physical characteristics of the arteries.
They bear relationship to cardiac-arterial interactions of the various arterial wall properties. Values of pulse wave
velocity (PWV), especially the brachial-ankle PWV (baPWV) are a practical predictor of the severity of atherosclerosis
in adults. However, changes of value of baPWV in healthy children (8-19 years old) have rarely been assessed. We
therefore investigated the changes in values of baPWV in healthy Taiwanese children.
Method: Between Oct. 2004 and Dec. 2005, in the Pediatric Cardiovascular Outpatient Department of Kaohsiung
Veterans General Hospital, we measured values of baPWV and other vital measurements in 123 healthy (systolic
blood pressure (SBP) † 120 mmHg, body mass index (BMI) † 24 and no underlying heart disease) children (51
boys and 72 girls). The relationship between baPWV and vital measurements was analyzed by linear regression and
step-wise multiple linear regression using SPSS 10.0 software.
Result: The value of baPWV could be predicted by ankle diastolic pressure (aDBP) and body height (Ht) (baPWV =
279.78 + 5.02 * aDBP + 2.67 * Ht, p < 0.05). It also increased with age, body weight (Wt), brachial systolic blood
pressure (bSBP), and brachial diastolic blood pressure (bDBP), independently. It was not statistically correlated
with BMI, heart rate (HR) or ankle systolic blood pressure (aSBP).
Conclusion: Based on our results, it is worthwhile to use values of baPWV as indicators of changes in arterial wall
properties in healthy Taiwanese children.
Key Words:
Pulse wave velocity · Blood pressure · Body mass index
tion.1 It is believed that the value of baPWV increases
with age and is a practical predictor of the severity of
atherosclerosis in adults.
Although atherosclerosis is rare in childhood, it is
important to emphasize the ability of reference values of
baPWV to reflect changes in arterial walls in children. In
the past, there have been few studies 2-5 of developing
children in other countries, or of adults in Taiwan. 6
Therefore, we investigated values of baPWV and analyze correlations between baPWV and vital measurements in healthy Taiwanese children.
INTRODUCTION
Arterial wall properties are important parameters reflecting the physical characteristics of the arteries. They
bear relationship to cardiac-arterial interactions of the
various arterial wall properties. Measuring the value of
baPWV is recognized as a simple and non-invasive method of screening for arterial stiffness in a large popula-
Received: May 8, 2007
Accepted: December 24, 2007
1
Department of Pediatrics, E-Da Hospital/I-Shou University;
2
Department of Pediatrics, Veterans General Hospital, Kaohsiung,
Taiwan.
Address correspondence and reprint requests to: Dr. Kai-Sheng
Hsieh, Department of Pediatrics, Veterans General Hospital, No. 386,
Ta-Chung 1st Rd, Kaohsiung 81364, Taiwan. Tel: 886-7-342-2121
ext. 8202; E-mail: [email protected]
METHODS
Between Oct. 2004 and Dec. 2005, we routinely
measured values of baPWV, blood pressures of four
35
Acta Cardiol Sin 2008;24:35-8
Chin-Fu Wang et al.
both prepubescent and postpubescent females were lower than those in the corresponding male groups (Table
3). In order to clarify the interactions among baPWV,
age and gender, two-way ANOVA was performed. The
results are shown in Table 4. The linear regression analysis of the values of baPWV and each correlated factor is
shown in Figure 1.
According to the results of step-wise multiple linear
limbs, heart rate, body height, and body weight in 123
healthy children (8-19 years old, 51 boys and 72 girls) in
the Pediatric Cardiovascular Outpatient Department of
Kaohsiung Veterans General Hospital.
Patients were examined in supine position, and
sphygmomanometer cuffs were wrapped on the brachia
and ankles. The cuffs inflated and deflated automatically, and pulse wave contours from the four extremities
were recorded simultaneously. Pulse transit time between the brachial and ankle regions was computed from
the pulse volume recording. Brachial-ankle PWV was
determined from the pulse transit time and the distance
between these two segments. The distance of each segment was calculated automatically, based on the height
of the subject. 5 All measurements were taken by the
same technician using the volume plethysmographic machine, Colin VP-1000 (Made in Japan).7
The inclusion criteria for subjects in our study were
(1) normal age-related SBP († 120 mmHg), (2) normal
age-related BMI († 24), (3) absence of underlying cardiovascular disease, and (4) absence of lipid disorder as
reported by the family. The reference values of age-related SBP and BMI were published by the Department of
Heath in Taiwan, 2002.
Values of baPWV and blood pressures of the right
arm and ankle were included in the analysis. We divided
the subjects into groups on the basis of gender and pubescent stage. The values of baPWV, age, Ht, Wt, blood
pressure, HR and BMI were analyzed by linear regression and step-wise multiple linear regression, using
SPSS 10.0 software.
Table 1. Characteristics of subjects
n = 123
Age (years)
Wt (kg)
Ht (cm)
BMI (kg/m2)
HR (bpm)
rbaPWV (cm/s)
lbaPWV (cm/s)
rbSBP (mmHg)
rbDBP (mmHg)
lbSBP (mmHg)
lbDBP (mmHg)
raSBP (mmHg)
raDBP (mmHg)
laSBP (mmHg)
laDBP (mmHg)
Female (72)
12.1 ± 2.7
046.6 ± 11.7
154.5 ± 15.1
19.2 ± 2.3
072 ± 11
1011 ± 159
0996 ± 142
108 ± 90
57 ± 5
109 ± 90
58 ± 6
125 ± 21
61 ± 8
121 ± 17
62 ± 8
12.7 ± 3.0
42.4 ± 8.3
150.6 ± 10.8
18.6 ± 2.3
071 ± 11
0979 ± 159
0959 ± 153
105 ± 90
57 ± 7
105 ± 90
57 ± 6
114 ± 15
61 ± 9
112 ± 13
60 ± 8
P
< 0.05
< 0.05
< 0.05
< 0.05
< 0.05
Wt: weight; Ht: height; BMI: body mass index; HR: heart
rate; rbaPWV: right brachial-ankle pulse wave velocity;
lbaPWV: left brachial-ankle pulse wave velocity; rbSBP: right
brachial systolic blood pressure; rbDBP: right brachial diastolic
blood pressure; lbSBP: left brachial systolic blood pressure;
lbDBP: right brachial diastolic blood pressure; raSBP: right
ankle systolic blood pressure; raDBP: right ankle diastolic
blood pressure; laSBP: left ankle systolic blood pressure;
laDBP: left ankle diastolic blood pressure.
RESULTS
Table 2. Pearson’s correlations of rbaPWV with each factor
On the basis of gender, the characteristics of the two
groups are summarized in Table 1. Systolic blood pressure and body weight were higher in the male group than
in the female group. Although there was no statistically
significant difference between baPWV in the two groups,
female subjects had smaller values of baPWV than males. Correlations between baPWV and each factor are
shown in Table 2. In females, age, Ht, Wt, bSBP, bDBP,
and aDBP correlated positively with baPWV. This was
different from males.
On the other hand, values of baPWV in groups of
Acta Cardiol Sin 2008;24:35-8
Male (51)
Age
Wt
Ht
BMI
HR
rbSBP
rbDBP
raSBP
raDBP
Male (51)
Female (72)
All (123)
0.218
0.203
0.234
-0.0210.104
0.176
*0.310*
0.023
**0.419**
*0.352**
0.276*
0.283*
0.117*
-0.037-*
*0.331**
0.300*
0.208*
0.248*
0.287**
0.251**
0.266**
0.073**
0.021**
0.281**
0.300**
0.138**
0.316**
*P < 0.05; **P < 0.01
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Brachial-Ankle Pulse Wave Velocity in Children
Table 3. rbaPWV (Mean ± SD, cm/s) of subjects divided on the
basis of pubescent stage
Male
Prepuberty (8~11 y/o)
Postpuberty (12~19 y/o)
n = 22
960 ± 179
n = 29
1050 ± 1320
Female
Table 4. Two-way ANOVA of rbaPWV for age and gender
Variable
P
Sex
Age
Sex * Age
n = 27
> 0.05
929 ± 129
n = 45
> 0.05
1009 ± 1680
F
P
1.015
1.909
1.465
< 0.05
Figure 1. Relationships between rbaPWV and vital measurements (95% confidence interval).
regression analysis with a 95% confidence interval, the
value of baPWV was dependent on both aDBP and Ht
(baPWV = 279.78 + 5.02 * aDBP + 2.67 * Ht, p < 0.05).
male hormones affect the changes of arterial stiffening.
However, in our study, prepubescent females had smaller
values of baPWV than males (Table 3). We consider that
precocious puberty may result those differences from
other reports.5,8,9 On the other hand, age was positively
correlated with baPWV in all subjects and females but
not in males. We found the interaction of age and gender
did not statistically affect the values of baPWV (Table
4). This result was also different from that in other reports. Nevertheless, the females had lower values of
baPWV than the males.
The structures of vessels change when an increase in
DISCUSSIONS
According to previous studies in children5 and adults, females have lower values of baPWV than males.
Other studies8-10 reported that values of baPWV in prepubescent females were higher than those in males and
then became lower after puberty. It was believed that fe8,9
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Acta Cardiol Sin 2008;24:35-8
Chin-Fu Wang et al.
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arterial compliance and left ventricular load in a northern Chinese
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3. Cheung YF, Brogan PA, Pilla CB, et al. Arterial distensibility in
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547-51.
5. Niboshi A, Hamaoka K, Sakata K, et al. Characteristics of
brachial-ankle pulse wave velocity in Japanese children. Eur J
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6. Chuang SY, Chen CH, Cheng CM, Chou P. Combined use of
brachial-ankle pulse wave velocity and ankle-brachial index for
fast assessment of arteriosclerosis and atherosclerosis in a community. Int J Cardiol 2005;98(1):99-105.
7. Munakata M, Ito N, Nunokawa T, et al. Utility of automated
brachial ankle pulse wave velocity measurements in hypertensive
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2003;30:303-9.
10. Ahimastos AA, Formosa M, Dart AM, et al. Gender differences in
large artery stiffness pre- and postpuberty. J Clin Endocrinol
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structure and function in hypertension. Naunyn Schmiedebergs
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in treated hypertensive subjects over a 6-year period. Circulation
2002;105:1202-7.
13. Boutouyrie P, Tropeano AI, Asmar R, et al. Aortic stiffness is an
independent predictor of primary coronary events in hypertensive
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14. Shiotani A, Motoyama M, Matsuda T, et al. Brachial-ankle pulse
wave velocity in Japanese university students. Intern Med 2005;
44(7):696-701.
15. Nakamura U, Iwase M, Nohara S, et al. Usefulness of brachialankle pulse wave velocity measurement: correlation with abdominal aortic calcification. Hypertens Res 2003;26:163-7.
16. Okamura T, Moriyama Y, Kadowaki T, et al. Noninvasive measurement of brachial-ankle pulse wave velocity is associated with
serum C-reactive protein but not with alpha-tocopherol in Japanese middle-aged male workers. Hypertens Res 2004; 27:173-80.
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blood pressure causes an augmentation of vascular tension.11-13 Increased cardiac output associated with age also
strongly affects increases in blood pressure, and age-related increases in values of baPWV. In our study, blood
pressure correlated positively with baPWV but heart rate
did not. These results imply that heart rate can not statistically represent cardiac output, although cardiac output is
the product of heart rate and stroke volume (CO = HR ´
SV). Unfortunately, we did not measure the stroke volume or ejection fraction in children by echocardiography. The values of cardiac output were not available.
The value of BMI is usually considered to be a predictor of obesity, but it is not proportional to serum lipid
levels. Therefore, higher BMI values are not correlated
with hyperlipidemia, which predisposes to atherosclerosis. Several previous studies14-17 reported that baPWV
was positively correlated with serum lipid levels but not
with BMI. Although BMI is proportional to body weight,
these measurements have different influences on the
values of baPWV. Our results show that body weight
correlated positively with baPWV but BMI did not. In
addition, we did not check the serum lipid levels in subjects, so the relationship between baPWV and serum lipid levels was not clear.
Although no subjects suffered cardiovascular disease, higher values of baPWV were measured in many
patients. According to their family’s description, no lipid
disorder had previously been found. Therefore, in order
to know the exact metabolic conditions in our subjects,
examinations of lipid profiles should be considered.
According to our results, it is worthwhile to use values of baPWV as indicators of changes in arterial walls
in healthy Taiwanese children. The values provide information regarding the health of developing children. In
Taiwan, baPWV in adults has been studied.6 The results
were consistent with those in previous studies elsewhere.
More studies are necessary to determine and elaborate
on the clinical significance of values of baPWV in children’s development.
REFERENCES
1. Yamashina A, Tomiyama H, Takeda K, et al. Validity, reproducibility, and clinical significance of noninvasive brachial-ankle
wave velocity measurement. Hypertens Res 2002;25:359-64.
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