Prevalence of hypertension among
schoolchildren aged 13-18 years in Gemlik,
Turkey
EMEL IRGIL, YASAR ERKENCI, NECLA AYTEK1N, HAMDI AYTEKIN *
Arterial hypertension is the permanent elevation of blood pressure (BP). Previous studies have documented that
hypertension may begin in adolescence, perhaps even in childhood. The purpose of this study was to determine the
prevalence of hypertension among adolescents in the Gemlik Research and Training Area, Turkey. Between January and
March 1994, all secondary and high school students aged 13-18 years were included in this study. An elevated BP was
defined according to the Report of the Second Task Force on Blood Pressure Control in Children. Of the 3,641 students
screened, 262 (7.2%) had elevated systolic and/or diastolic BP, 161 (4.4%) students had significant hypertension
and 101 (2.8%) students had severe hypertension. We found that systolic and diastolic BP increased with age, height and
weight. BP measurements should be included in physical examinations as part of the continuing care of the child.
Key words: hypertension, prevalence, schoolchildren
Arterial hypertension is the permanent elevation of MATERIALS AND METHODS
blood pressure (BP). The prevalence of hypertension is The study was conducted between January and March
reported as being 1-30% among adults in different age 1994. All secondary and high school students aged 13-18
groups. It has been recognized since the 1950s that hyper- years were included in this study. Our target population
tension is a major risk factor for cardiovascular morbidity was 3,681 students and we managed to contact 3,641
and mortality.1 Previous studies have documented that (98.9%) of them. One medical doctor, one nurse and one
hypertension may begin in adolescence, perhaps even in health worker received training in BP measurement at the
childhood.2"5 Early diagnosis, treatment, follow-up of the Department of Nephrology in Uludag University Medical
hypertensive cases and preventive methods such as de- School. Standard adult sphygmomanometers (Erkameter,
creasing weight to the ideal, increasing physical activity width 13 cm and length 23 cm) were used. The screening
and changing eating habits may decrease future hyper- team explained to the students the purpose of the study
tension morbidity and mortality. and how BP is measured before the measurements were
Early diagnosis of hypertensive cases in adolescence can be carried out. When a student was absent, the team went to
a problem because subjects in this age group are generally the school for a second time. The students rested for at
healthy and see a physician only when they are acutely least 15 minutes before the measurement was taken. The
ill. For this reason, BP should be measured routinely in BP measurements were done in a separate and silent room,
children aged three years and older during well-child in a comfortable sitting position, with the right arm fully
examinations.''8 High school screening assessments can exposed and resting on a table at heart level. The onset
be an effective way of finding adolescents with elevated of the tapping sound (Korotkoff I = phase I) corresponds
BP, particularly those who are being missed by traditional to the systolic BP. The diastolic BP is characterized by the
health care delivery. In addition, in a previous study among disappearance of all sounds (Korotkoff V = phase V) for
adolescents 13-18 years of age.7adults in Gemlik, the prevalence of hypertension was  The data collected in-
higher than in the other studies carried out in Turkey. cluded name, age, sex, height and weight. An elevated BP
In Turkey, there has been no population study among was defined according to the Report of the Second Task
adolescents. Previous studies were conducted in clinics so the Force on Blood Pressure Control in Children-1987.
results were not representative of the whole population. According to this report, for adolescents aged 13-15 years
In order to make up for this lack of knowledge, we con- the significant hypertension limits are systolic BP >136
ducted a population study among adolescents in the Gem- mmHg and diastolic BP >86 mmHg and the severe hyper-
lik Research and Training Area, Turkey. tension limits are systolic BP S144 mmHg and diastolic
BP S92 mmHg. For older adolescents (aged 16-18 years),
these limits are systolic BP £142 mmHg and diastolic BP
* E. Irgll', Y. Erkenci', N. AytekJn", H. Aytekin'
1 Uludag University Medical School, Department of Publk Health. Buna. £92 mmHg and systolic BP SI50 mmHg and diastolic BP
Turkey >98 mmHg respectively.7
Correspondent*: Emel Irgll, MD, Uludag University Medical School.
Department of Public Health, 16059 GOrukle - Buna, Turkey, If the systolic and/or diastolic BPs were elevated, the
tel. +90 224 4428313. fax + 90 224 5132717 measurements were repeated after 15 min (second meas-
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Hypertension among schoolchildren
urement). Students in whom both BPs (first and second tension screening is not recommended in children and
measurements) were high, were measured for a third time adolescents by the WHO,10 we conducted this prevalence
one month later. The students whose second and third survey because we have no data on the prevalence of
measurements were evaluated as normal, were followed hypertension among adolescents in our country. Screen-
up periodically. Students in whom all three measurements ing was the only way to obtain the figures.
were high were called to the out-patient clinic of the Many studies have documented that hypertension may
Department of Nephiology in the Uludag University begin in childhood. This finding has had an impact on
Medical School in order to find the aetiologic factor and the improvement of diagnostic and therapeutic methods,
provide treatment. as well as the development of preventive measures against
After the analysis, it was found that there was no statist- the causative factors of hypertension.
ically significant difference between the first and second In different studies, the prevalence of hypertension was
measurements, so only the first BP values were evaluated. calculated among different age groups.11"21 As shown in
Analyses were performed with the EPI INFO Program. table 3, we found the second highest prevalence among
adolescents. In the previous study among adults in Gem-
RESULTS lik, a higher prevalence of hypertension was also found.9
Of the 3,641 students screened, 1,574 (43.2%) were girls The reason for this discrepancy should be investigated by
and 2,067 (56.8%) were boys. Table I presents the means conducting further studies.
and standard deviations of
height, weight, body mass in- Table 2 Classification of hypertension by age groups
dex and systolic and diastolic Significant Severe
BPs by age for girls and boys. Age groups Normal hypertension hypertension Total
Up to 16 years of age, BP in- (years) n % n %
creased with age among girls 13-15 2,325 91.6 147 5.8 67 2.6 2,539 100.0
and then a decrease was ob- 16-18 1,054 95.6 14 1.3 34 3.1 1,102 100.0
served. The BP values in-
creased with age among boys. Total 3379 92.8 161 4.4 101 2.8 3,641 100.0
According to the Second
Task Force on Blood Pres-
sure Control in Children- Table 3 Results of some studies on hypertension
1987,7 of the 3,641 students
Study Age group Prevalence of
screened, 262 (7.2%) had Residence population (years) hypertension
elevated systolic and/or dia- Edirne, Turkey 968 7-11 6.2
stolic BP, 161 (4.4%) stu- Sao Paulo, Brasil12 1,000 6-18 6.9
dents had significant hyper- St Paul and Minneapolis, Minnesota, USA 14,686 10-15 4.2
tension and 101 (2.8%) Port Moresby, PNGH 626 8-16 5.1
students had severe hyper- Baden Wurttenberg, Germany1 410 4-18 2.9
tension. Table 2 represents Cordoba, Argentina 1,698 4-18 3.4
the classification of hyper- Aligarh, India17 3,861 5-15 6.6
tension by age groups. Jaipur, India 1,500 5-12 2.9
India" 2,073 5-14 2.9
DISCUSSION Tulsa, Oklahoma, USA20 5,537 14-19 6.0
Hypertension rarely pro- Napoli, Italy21 168 11 8.0
duces symptoms in the early
Gemlik, Turkey 3,641 13-18 7.2
years of life. Although hyper-
Table 1 The means and standard deviations (sd) of male and female subjects' height, weight, body mass index (BMI) and diastolic blood
pressures (DBP) and systolic blood pressure (SBP) by age
Age (years) Height (cm) Weight (kg) BMI DBP (mmHg) SBP (mmHg)
M F M F M F M F M F M F
n n Mean±sd Mean±sd Mean ± sd Mean ± sd Mean ± sd Mean ± sd Mean ± sd Mean ± sd Mean ± sd Mean ± sd
13 535 447 157.4 ±9.8 156.5 ±6.5 48.8 ±9.5 50.1 ±8.5 19.5 ±2.5 20.4 ±3.0 70.2 ± 10.4 73.8 ± 8.4 109.6±123 111.7±10.8
14 446 376 163 J ± 9.0 158.5 ±6.5 53.9 ±9.4 52.1 ±7.1 20.1 ±2.6 20.8 ±2.8 71.4 ± 10.5 75.1 ±9.6 112.3112.1 114.7±12.2
15 401 334 169.1 ±7.8 160.3 ±6.9 59J ± 10.0 53.61 7.4 20.7 ±2.8 20.9 ±2.8 74.9 ± 9 3 76.5 ±9.8 116.0±12.7 114.2±13.O
16 376 281 171.3± 7.0 16O.5±5.9 61.9±9.7 55.3±8.3 21.1 ± 2.9 21.5 ± 3.1 77.1 ±10.7 77.2 ±8.6 118.7±13.5 115.2111.0
17 202 96 172.0 ±6.1 159.7 ±6.8 63.7 ±8.8 54.5 ±6.4 21.5 ±2.8 21.4 ±2.5 77.0 ±9.8 74.9 ±8.8 118.7112.0 113.6±11.9
18 107 40 172.7 ±6.7 158.2 ±7.1 65.0 ±8.0 53.9 ±7.3 21.812.8 21.5 ±2.2 76.4 ±10.5 77.3 ±8.2 118.8112.7 113.9112.3
M: male; F: female
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EUROPEAN JOURNAL OF PUBLIC HEALTH VOL. 8 1998 NO. 2
In our study, we found that systolic and diastolic BP to middle age. The Dormont high school follow-up study,
1957-1963 to 1989-1990. Am J Epidemiol 1993; 138(11)^73-83.
increased with age, height and weight. Previous studies 6 Andersen LB, Henckel P, Saltn B. Risk factors for
have shown that the influence of maturation of the body cardiovascular disease in 16-19-year-old teenagers. J Int Med
is more important than age.3 '4 '7 '15ll9 '2O '22~28It is not a 1989,225:157-63.
7 Report of The Second Task Force on Blood Pressure
general rule that BP increases with weight. Race and Control in Children-1987. Pediatrics 1987;79(1):1-25.
ethnic groups may influence BP. For example, one study 8 Daniels SR. Primary hypertension in childhood and
found that Southeast Asian refugee children had greater adolescence. Pediatr Ann 1992;21(4):226-9.
9 Erkend Y. Umurbey KoyQnde Hipertansiyon Prevalansi ve
mean systolic BP than did black and white American Risk Faktorleri (Prevalence of hypertension and risk factors in
children across all weight strata. Umurbey) (dissertation). Bursa: Uludag University, 1990.
In our study, the BP levels increased up to 16 years of age 10 Braveman PA, Tarimo E, editors. Screening in primary
health care: setting priorities with limited resources. WHO:
among girls and then a decrease was observed. The mean Geneva, 1994.
values of height and weight also decrease among 17 and 11 Dlndar I, Sartik A. Edirne Merkezlnde 7-11 Yas Grubu 968
18 year old girls. In a study conducted in Sao Paulo similar Ilkokul Cocugunda Hipertansiyon Taramasi (Hypertension
screening among primary school children aged 7-11 in Edirne,
results were obtained. In our study, the number of 17 Turkey). Proceedings of the Fourth National Congress of Public
and 18 year old girls were few. The reason for this may Health; 1994 Sept 16-20; Didim. Izmir 9 Eylul University Medical
probably be early marriage. In Turkey, approximately half School; Ege University Medical School; Izmir Chamber of Medicine
1994:436-40.
of the women are married at the age of 18 years. In 12 Simonatto DM, Dias MD, Machado RL, Abensur H, Cruz J.
particular in rural areas, it is very probable that the girls Arterial hypertension in students of the Great Sao Paulo area.
who mature earlier will leave school and get married at Rev Assoc Med Bras 1991;37(3):109-14.
13 Sinaiko AR, Gomez-Marin O, Prineas RJ. Prevalence of
younger ages. For this reason, the results of the 17—18 'significant1 hypertension in junior high school-aged children: the
year old girls may not be representative of the whole children and adolescent blood pressure program. J Pediatr
population. 1989;114:664-9.
14 Ampofo EK. Blood pressure distribution in children at Port
The BP of most adolescents and children is not measured Moresby, Papua New Guinea. PNG Med J 1989;32(2):101-8.
during routine physical examinations. In a study done in 15 Klimm HD, Reuter-Kuhn I. Pravalenz der Hypertonie im
Edirne (Turkey), it was pointed out that none of the Kindesahten eine Untersuchung in 21 Hausarztlichen Praxen
(Prevalence of hypertension in childhood: a study of 21 family
hypertensive children's BP had been measured before. physician practices). Fortschr Med 1994;112(5):49-52.
In our study, the hypertensive subjects were similarly 16 Lodolo AD, Novoa P, Sakuyama E, Lodolo MM, Palma JA,
unaware. Martinez JR. Arterial hypertension in childhood and adolescence.
Rev Fac Cien Med Univ Nac Cordoba 1989;47(1-2):19-22.
The proposal to measure BP once a year among children • 17 Gupta AK, Ahmad AJ. Normal blood pressures and the
diree years of age through to adolescence as recommended evaluation of sustained blood pressure elevation in childhood.
in the Report of Second Task Force on Blood Pressure Indian Pediatr 199O;27(1):33-42.
7 18 Mangal N, Bansal RK, Barar V, et al. Blood pressure studiesControl in Children-1987  could be achieved with die in Jaipur children. Indian Pediatr 1989;26(4):358-65.
minimum of effort in our country. Midwives whose duties 19 Laroia D, Sharrna M, Diwedi V, Belapurkar KM, Mathur PS.
are to follow up children of up to 6 years of age could also Profile of blood pressure in normal school children. Indian Pediatr
1989;26(6):531-6.
measure BP. Training midwives about the right measure- 20 O'Quin M, Sharma BB, Miller KA, Tomsovic JP. Adolescent
ment techniques can be done with little effort. BP meas- blood pressure survey: Tulsa, Oklahoma, 1987 to 1989. S Med J
urements should be included in physical examinations as 1992;85(5):487-90.
21 Ferrara LA, Marotta T, Mainenti G, Borrelli R, Mancini M,
part of the continuing care of the child, not as an isolated Soro S. Resting blood pressure and cardiovascular response to
procedure. In Turkey, health centers are responsible for sympathetic stimulation in adolescents. Int J Cardiol
school health. Measuring the BP of the schoolchildren 1992;36(2):197-201.
22 St.George IM, Williams SM, Silva PA. Blood pressure level,
should be added to routine school health examinations. trend and variability in Dunedin children: an 8-year study of a
The public should be taught that hypertension is not only single birth cohort. Circulation 1990,82:1675-80.
a disease of adulthood. People should be educated in order 23 Tdrok E, Gyarfas I, Csukas M. Factors associated with stable
to encourage physical exercise and change eating habits high blood pressure in adolescents. J Hypertens
1985;3(suppl.3):389-90.
that may both protect them from cardiovascular diseases 24 Bendersky M, Resk J, Kuschnir E, et al. Blood pressure
and decrease their weight to the ideal. control in children of Cordoba, Argentina. Hypertension
1992;19(suppl.2):11273-8.
25 Hansen HS, Nielsen JR, Hyldebrandt N, Froberg K. Blood
pressure and cardiac structure in children with a parental history
of hypertension: the Odense schoolchild Study. J Hypertens
1992;10(7):677-82.
1 Hypertension in developing countries. WHO Statistics 26 Munger RG, Gomez-Marin O, Prineas RJ, Sinaiko AR.
Quarterly 1988;41(3/4). Elevated blood pressure among Southeast Asian refugee children
2 de Man SA, Andre JL, Bactimann H, et al. Blood pressure in in Minesota. Am J Epidemiol 1991;133(12):1257-65.
childhood: pooled findings of six European studies. J Hypertens 27 Gupta AK, Ahmad AJ. Childhood obesity and hypertension.
1991;9:109-14. Indian Pediatr 1990;27(84):333-7.
3 Kotchen JM, McKean HE, Neill M, Kotchen TA. Blood 28 Turkish Government, UNICEF. Turfciye'de Anne ve
pressure trends associated with changes in height and weight Cocuklarin Durum Analizi (The situations of mothers and children
from early adolescence to young adulthood. J Clin Epidemiol in Turkey). T.C. HOkOmeti- UNICEF Is Birligi Program!
1989;42(8):735-41. (Coordination Program Between Turkish Government and
4 Uhari M, Nuutinen EM, Turtinen J, et al. Blood pressure in UNICEF). Ankara: Turkish Government 1991:253.
children, adolescents and young adults. Ann Med 1991;23:47-51.
5 Yong IX, Kuller LH, Rutan G, Bunker C. Longitudinal study
of blood pressure: changes and determinants from adolescence Received 24 January 1996, accepted 29 May 1996
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