Obesity in Indian children: Time trends and relationship with hypertension

Article (PDF Available)inThe National medical journal of India 20(6):288-93 · November 2006with19 Reads
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Abstract
Limited data are available from India regarding the distribution and profile of childhood obesity and hypertension. We examined the time trends in childhood obesity in a representative sample of schoolchildren from Ernakulam District, Kerala and determined the relationship of obesity with blood pressure. We used a stratified random cluster sampling method to select the children. Anthropometric data were collected from 24 842 students, 5-16 years of age, during 2003-04. Blood pressure and anthropometric data were collected from 20 263 students during 2005-06. Overweight and obesity were defined by body mass index for gender and age. Gender, age and height were considered for determining hypertension. The proportion of overweight children increased from 4.94% of the total students in 2003 to 6.57% in 2005 (OR: 1.36; 95% CI: 1.25-1.47; p < 0.0001). The increase was significant in both boys and girls. The proportion of overweight children was significantly higher in urban regions and in private schools, and the rising trend was limited to private schools. Systolic or diastolic incident hypertension was found in 17.34% of overweight children versus 10.1% of the remaining students (OR: 1.87; 95% CI: 1.60-2.17; p < 0.0001). Childhood obesity showed an increasing trend in a short period of 2 years. Hypertension was common in overweight children. The results suggest the need for greater public awareness and prevention programmes on childhood obesity and hypertension.
288 THE NATIONAL MEDICAL JOURNAL OF INDIA VOL. 20, NO. 6, 2007
Obesity in Indian children: Time trends and relationship
with hypertension
MANU RAJ, K. R. SUNDARAM, MARY PAUL, A. S. DEEPA, R. KRISHNA KUMAR
ABSTRACT
Background. Limited data are available from India regarding
the distribution and profile of childhood obesity and hypertension.
We examined the time trends in childhood obesity in a represen-
tative sample of schoolchildren from Ernakulam District, Kerala
and determined the relationship of obesity with blood pressure.
Methods. We used a stratified random cluster sampling
method to select the children. Anthropometric data were
collected from 24 842 students, 5–16 years of age, during
2003–04. Blood pressure and anthropometric data were
collected from 20 263 students during 2005–06. Overweight
and obesity were defined by body mass index for gender and
age. Gender, age and height were considered for determining
hypertension.
Results. The proportion of overweight children increased
from 4.94% of the total students in 2003 to 6.57% in 2005
(OR: 1.36; 95% CI: 1.25–1.47; p<0.0001). The increase
was significant in both boys and girls. The proportion of
overweight children was significantly higher in urban regions and
in private schools, and the rising trend was limited to private
schools. Systolic or diastolic incident hypertension was found in
17.34% of overweight children versus 10.1% of the remaining
students (OR: 1.87; 95% CI: 1.60–2.17; p<0.0001).
Conclusion. Childhood obesity showed an increasing trend
in a short period of 2 years. Hypertension was common in
overweight children. The results suggest the need for greater
public awareness and prevention programmes on childhood
obesity and hypertension.
Natl Med J India 2007;20:288–93
INTRODUCTION
Childhood overweight and obesity are global problems that are
on the rise.
1
Obesity in children appears to increase the risk of
subsequent morbidity, whether or not obesity persists into
adulthood.
2
Outcomes related to childhood obesity include
hypertension, type 2 diabetes mellitus, dyslipidaemia, left
ventricular
hypertrophy, non-alcoholic steatohepatitis, obstructive
sleep
apnoea, and orthopaedic and psychosocial problems.
3–5
According to WHO, 22 million children (under 5 years of age)
are overweight.
1
Obesity is evolving as a major nutritional problem
in developing countries, affecting a substantial number of adults
and resulting in an increased burden of chronic disease.
1
In
national surveys conducted in the USA from the 1960s to the
1990s, the prevalence of overweight in children increased from
5% to 11%.
6
Studies on urban Indian schoolchildren from selected regions
report a high prevalence of obese and overweight children.
7–11
In
addition, studies on Indian schoolchildren have also demonstrated
that the prevalence of hypertension in overweight children is
significantly higher than that among normal children.
12–15
Till date no nationally representative data have emerged from
India, which makes it difficult to project the prevalence of obesity
and overweight among children in India. We aimed to determine
the time trends of childhood obesity and overweight in a large
population of schoolchildren from Ernakulam, Kerala, over a
period of 2 years. The relationship of obesity with childhood
hypertension was also explored.
METHODS
A contiguous area with a population of approximately 1.37
million was selected from Ernakulam district, in central Kerala.
In the list of schools obtained from the District Education Office,
Ernakulam, there were 377 schools with a total student strength of
202 710 in the area. Sampling was done by the stratified random
cluster sampling method. The primary component of the study
necessitated a sample size of 25 000. Schools were stratified into
5 groups according to the strength of children and a representative
sample of 46 schools with a cumulative population of 25 228
children was randomly chosen. Consent to conduct the school
survey and blood pressure measurement of the students was
obtained from parents through school authorities who arranged
parent meetings in the respective schools. Verbal assent was
taken from the children after demonstrating and explaining the
procedure.
Anthropometric data (height and weight) were collected from
24 842 students, 5–16 years of age, during 2003–04. Blood
pressure and anthropometric data were collected from 20 263
students, 5–16 years of age, during the period 2005–06. Children
with a body mass index (BMI)
>85th percentile of reference data
were considered overweight and those with a BMI
>95th percentile
were considered obese.
3
The reference data used to identify the
cut-off points were taken from the CDC 2000 dataset for BMI.
16
Blood pressure (BP) was measured using standard methodology
as recommended by The Fourth Report on the diagnosis, evaluation
and treatment of high blood pressure in children and adolescents.
17
Average systolic or diastolic BP
>95th percentile for gender, age
and height was considered as hypertension. Pre-hypertension was
defined as average systolic BP or diastolic BP that was
>90th
© The National Medical Journal of India 2007
Amrita Institute of Medical Sciences and Research Centre, Kochi, Kerala,
India
MANU RAJ, MARY PAUL, A. S. DEEPA, R. KRISHNA KUMAR
Department of Paediatric Cardiology
K. R. SUNDARAM Department of Biostatistics
Correspondence to R. KRISHNA KUMAR;
rkrishnakumar@aims.amrita.edu
289
percentile but <95th percentile. Children with BP levels
>120
mmHg systolic and/or 80 mmHg diastolic were also considered
pre-hypertensive.
17
Children from the representative sample were called for
screening according to their classes and were given rest for 5
minutes. The procedures were explained briefly and demonstrated
to them. Those children who were cooperative and relaxed
underwent BP measurement. Others were given adequate time to
come to terms with the procedures. The BP was measured using
a standardized mercury sphygmomanometer and recorded by
trained paramedical personnel. BP was measured in a sitting
posture with the hands resting on the examining table with the
cubital fossa supported at the level of the heart. Chairs of adequate
height were used for various groups. The stethoscope was placed
over the brachial artery pulse, proximal and medial to the cubital
fossa and below the bottom edge of the cuff (i.e. about 2 cm above
the cubital fossa). Cuffs having a bladder width approximately
40% of the arm circumference midway between the olecranon and
the acromion were used. The BP measurement was done on the
right arm for consistency and comparison with standard tables.
Three readings of the BP of each child were taken, maintaining an
interval of 2 minutes between readings. The mean of 3 readings
was reported. The weight and height of each child were recorded.
Height was measured by a WHO-approved wall-mounted height
measuring scale. A calibrated and standardized mechanical
weighing scale was used to measure weight.
Statistical analysis
Statistical significance of the difference in the mean value of
different variables between the 2 groups was tested by applying
Student ‘t’ test. Odds ratio and the corresponding confidence
intervals were computed by using standard methods.
18
The SPSS
(version 11.0) software was used for this purpose.
RESULTS
In 2003, a total of 24 842 children (11 327 boys and 13 515 girls)
and in 2005, 20 263 children (9754 boys and 10 509 girls) were
examined. The descriptive data of both surveys are shown in
Tables I and II. Overweight (including obesity) was found in
4.94% of the total students in 2003 and 6.57% in 2005. This
increase is statistically significant (OR: 1.36; 95% CI: 1.25–1.47;
p<0.0001) and was seen in both sexes (Table III). A comparison
of mean BMI between 2003 and 2005 showed an increase across
all age groups. This increasing trend was seen in both boys and
girls (Fig. 1). The prevalence of overweight was more in the age
group of 5–11 years when compared with those in the age group
of 12–16 years in 2003 and 2005. The difference in prevalence of
overweight between the age groups was not statistically significant
in 2003 (5.08% v. 4.78%, p=0.29) but was significant in 2005
(7.08% v. 5.98%, p<0.005).
Comparisons were made between overweight percentages in
government and private schools (Table IV). Private schools had
a higher percentage of overweight children than government
schools, both in the 2003 (5.17% v. 3.83%; OR: 1.37; 95% CI:
1.15–1.62; p<0.0003) and 2005 datasets (7.17% v. 3.23%; OR:
2.31; 95% CI: 1.87–2.86; p<0.0001). An increasing trend was
apparent among private schools (OR: 1.42; 95% CI: 1.30–1.54;
p<0.0001) and not among government schools (OR: 0.84; 95%
CI: 0.65–1.09; p>0.05). A significantly higher proportion of
children from urban schools were obese compared with rural
schools both in 2003 and 2005. Both urban and rural schools
showed an increasing trend between 2003 and 2005 (Table V).
FIG 1. Body mass index (BMI) comparisons for 2003 and 2005
among girls and boys
RAJ et al. : OBESITY IN CHILDREN: TIME TRENDS AND RELATIONSHIP WITH HYPERTENSION
Blood pressure was examined in 20 263 children in the survey
done during 2005. Incident hypertension was seen in 10.58%
(7.17% in boys, 13.74% in girls) of total children. Systolic
290 THE NATIONAL MEDICAL JOURNAL OF INDIA VOL. 20, NO. 6, 2007
TABLE I. Descriptive data of school survey, 2003
Age Boys Girls
(years) n Height (cm) Weight (kg) BMI n Height (cm) Weight (kg) BMI
5 430 109.6 (6.23) 16.8 (2.86) 13.9 (1.38) 344 108.4 (5.33) 16.2 (2.29) 13.7 (1.50)
6 830 115.2 (5.59) 18.8 (3.27) 14.1 (1.68) 738 114.5 (6.04) 18.7 (3.53) 14.2 (1.79)
7 872 120.8 (6.17) 21.1 (4.11) 14.4 (1.88) 699 119.8 (6.08) 20.7 (3.91) 14.3 (1.81)
8 910 125.8 (6.19) 23.2 (4.38) 14.6 (1.84) 698 125.0 (6.42) 23.1 (4.98) 14.7 (2.12)
9 1016 131.2 (6.55) 25.9 (5.70) 14.9 (2.20) 1043 130.9 (6.55) 26.0 (5.59) 15.1 (2.31)
10 1235 135.5 (6.75) 28.3 (6.92) 15.3 (2.68) 1406 136.3 (7.09) 28.7 (6.33) 15.3 (2.45)
11 1213 140.4 (7.52) 31.0 (7.37) 15.6 (2.67) 1550 142.0 (7.47) 32.5 (7.36) 16.0 (2.72)
12 1340 145.7 (7.86) 34.4 (8.13) 16.1 (2.74) 1882 147.8 (7.14) 36.9 (7.95) 16.8 (2.80)
13 1266 152.8 (8.74) 39.7 (9.50) 16.8 (2.93) 2004 151.0 (6.57) 40.0 (7.59) 17.5 (2.73)
14 1282 158.6 (8.58) 44.0 (9.82) 17.3 (2.88) 1881 153.4 (6.05) 42.8 (7.79) 18.2 (2.83)
15 681 162.7 (8.04) 47.7 (9.71) 17.9 (2.80) 943 153.8 (5.80) 43.9 (7.55) 18.5 (2.88)
16 252 164.8 (7.43) 49.0 (9.12) 18.0 (2.56) 327 153.6 (6.17) 44.2 (7.75) 18.7 (2.93)
All values are mean (SD) BMI body mass index
TABLE II. Descriptive data of school survey, 2005
Age Boys Girls
(years) n Height (cm) Weight (kg) BMI SBP DBP n Height (cm) Weight (kg) BMI SBP DBP
5 198 111.6 (5.63) 17.8 (3.19) 14.2 (1.53) 95.2 (8.15) 61.0 (8.41) 222 110.0 (5.52) 17.2 (2.89) 14.2 (1.57) 94.1 (9.25) 5.92 (9.20)
6 689 116.1 (5.61) 19.5 (3.77) 14.4 (1.85) 96.5 (8.68) 60.9 (8.93) 563 114.8 (5.55) 18.9 (3.36) 14.2 (1.66) 95.9 (8.44) 61.7 (7.97)
7 729 122.0 (5.61) 21.9 (4.71) 14.6 (2.20) 97.7 (8.22) 62.9 (8.75) 594 121.6 (5.73) 21.8 (4.61) 14.6 (2.20) 97.9 (8.35) 63.3 (8.32)
8 788 127.4 (6.26) 24.5 (5.32) 15.0 (2.26) 99.5 (9.09) 64.3 (8.68) 667 126.2 (6.33) 23.8 (4.99) 14.8 (2.16) 98.8 (9.36) 63.7 (8.51)
9 912 132.1 (6.32) 26.8 (5.76) 15.2 (2.32) 100.5 (8.56) 66.0 (8.31) 855 132.3 (6.58) 26.7 (5.69) 15.1 (2.32) 101.5 (9.36) 66.5 (8.38)
10 1109 137.1 (6.48) 29.3 (6.50) 15.4 (2.48) 102.1 (8.67) 67.3 (8.08) 1178 137.6 (7.08) 29.9 (7.10) 15.7 (2.62) 104.4 (9.87) 68.5 (8.17)
11 1126 141.9 (7.24) 32.6 (7.94) 16.1 (2.83) 103.5 (9.60) 68.3 (8.24) 1301 142.8 (7.33) 33.7 (8.01) 16.3 (2.77) 107.3 (10.01) 70.0 (7.85)
12 1125 146.7 (7.87) 35.9 (9.13) 16.5 (2.96) 105.3 (10.00) 68.6 (8.08) 1269 148.6 (6.68) 38.2 (8.07) 17.2 (2.83) 109.8 (10.35) 71.7 (7.62)
13 1024 153.7 (8.83) 40.9 (9.71) 17.2 (2.99) 108.0 (11.20) 69.1 (8.67) 1388 152.1 (6.24) 41.5 (7.82) 17.9 (2.84) 112.3 (10.57) 72.6 (7.80)
14 1088 159.8 (8.36) 45.1 (9.60) 17.5 (2.79) 111.0 (11.29) 71.2 (8.25) 1481 154.2 (5.99) 44.0 (8.53) 18.5 (3.08) 113.2 (10.42) 73.3 (7.85)
15 687 164.2 (7.71) 49.3 (10.51) 18.2 (3.05) 113.8 (10.92) 72.8 (8.46) 813 155.3 (6.28) 45.8 (8.39) 19.0 (2.88) 114.4 (10.47) 74.2 (7.94)
16 279 165.9 (7.50) 52.4 (11.42) 18.9 (3.28) 115.1 (11.44) 73.2 (8.20) 178 155.2 (6.58) 46.6(8.92) 19.3 (3.28) 114.7 (10.87) 74.5 (7.10)
BMI body mass index SBP systolic blood pressure in mmHg DBP diastolic blood pressure in mmHg All values are mean (SD)
TABLE III. Percentages of overweight and obese children in 2005 and 2003
Dataset Overweight Obese
Overall Boys Girls Overall Boys Girls
2005 (n=20 263) 6.57
* 7.33 5.87 1.89* 2.47 1.34
2003 (n=24 842) 4.94
* 5.38 4.57 1.26* 1.65 0.93
Odds ratio 1.36* 1.39 1.30 1.51* 1.51 1.45
95% confidence interval 1.25–1.47 1.24–1.56 1.16–1.46 1.29–1.76 1.24–1.84 1.13–1.85
p value <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.003
* Odds ratio adjusted for gender and age
TABLE IV. Percentages and trends of overweight children in
private and government schools
Dataset Private Government Odds ratio, 95% CI,
schools schools p value
2005 7.17 3.23 2.31, 1.87–2.86, p<0.0001
2003 5.17 3.83 1.37, 1.15–1.62, p<0.0003
Odds ratio 1.42* 0.84*
95% CI 1.30–1.54 0.65–1.09
p value p<0.0001 p>0.05
* Odds ratio adjusted for gender and age CI confidence interval
TABLE V. Percentages and trends of overweight children in urban
and rural schools
Dataset Urban Rural Odds ratio, 95% CI, p value
2005 8.66 3.75 2.43, 2.13–2.77, p<0.0001
2003 6.43 2.91 2.29, 2.00–2.62, p<0.0001
Odds ratio 1.38* 1.30*
95% CI 1.26–1.52 1.11–1.53
p value p<0.0001 p<0.005
* Odds ratio adjusted for gender and age CI confidence interval
hypertension was seen in 5.84% (3.20% in boys, 8.29% in girls)
of children and diastolic hypertension in 6.61% (4.89% in boys,
8.2% in girls). Among the total children, 10.65% (9.33% in boys,
11.89% in girls) had systolic pre-hypertension and 14.75% (12.53%
in boys, 16.8% in girls) had diastolic pre-hypertension.
Systolic BP correlated better with weight (boys –r=0.559, girls
r=0.539) and diastolic BP with height (boys –r=0.399, girls
r=0.458). The correlation of BP with BMI was lower compared
with correlation of BP with weight as well as height in both sexes.
In both boys and girls, the mean systolic BP in the overweight
group was more than that in the normal weight group. In boys, the
mean diastolic BP in the overweight group was more than that in
the normal weight group in all ages except in those who were 15
years old. In girls, the mean diastolic BP in the overweight group
was more than that in the normal weight group in all age groups
(Table VI).
The prevalence of incident hypertension in normal weight,
overweight and obese groups was 10.1%, 17.34% and 18.32%,
respectively. In the total sample, children in the age group of 12–
16 years had a higher prevalence of incident hypertension when
291
compared with those in the age group of 5–11 years (13.18% v.
8.35%). The prevalence of systolic hypertension (first instance) in
normal weight, overweight and obese groups was 5.38%, 12.31%
and 14.66%, respectively. The prevalence of diastolic hypertension
(first instance) in normal weight, overweight and obese groups
was 6.45%, 8.86% and 8.9%, respectively. The sex-wise
differences in various blood pressures among the 3 weight groups
are given in Table VII.
DISCUSSION
Although the prevalence values of childhood obesity in this study
are lower than those of other studies from similar settings,
7–11
the
increasing trend of overweight and obesity in our study was
significant. During a short span of 2 years the proportion of
overweight children increased significantly across all age groups
and in both sexes. This was accompanied by an increasing trend
in mean BMI values across all age groups. The increase was
substantial in private schools and not seen in government schools.
Although urban schools had a higher proportion of overweight
children, both urban and rural schools showed an upward trend in
the 2-year period. This rapid increase in a short span of 2 years
assumes considerable epidemiological importance. A high BMI
correlates strongly with markers of secondary complications of
obesity including current blood pressures,
19–21
blood lipid and
lipoprotein levels
19,22–24
and long term mortality.
2
Evidence from several national health surveys in Asia points to
significant differences in prevalence of overweight and obesity
among countries.
25–29
Asian countries such as Taiwan and China
have experienced rapid increases in prevalence of childhood
obesity.
30,31
Rapid economic growth has improved the nutritional,
socioeconomic and health status of many countries.
32
Obesity has
increased markedly with this nutritional evolution in most Asian
countries.
33
A similar nutritional transition is under way in India as
well.
29
In addition to the nutritional and socioeconomic transitions,
the behavioural transition of children is also possibly contributing
significantly to the rapidly rising prevalence of obesity. Unhealthy
eating habits and physical inactivity are the major culprits.
34
The
sedentary lifestyle of children and adolescents have been attributed
mainly to television viewing, computer games, internet, over-
emphasis on academic excellence, unscientific urban planning
TABLE VI. Comparison of systolic blood pressure (SBP) and diastolic blood pressure (DBP) between normal and overweight groups
Age Group Boys Girls
(years) SBP (mmHg) DBP (mmHg) SBP (mmHg) DBP (mmHg)
Mean (SD) p value Mean (SD) p value Mean (SD) p value Mean (SD) p value
5 NW 95.1 (8.25) 0.295 60.8 (8.43) 0.065 93.7 (9.10) 0.004 58.8 (9.28) 0.001
OW* 97.9 (5.84) 65.8 (6.90) 101.6 (9.19) 65.1 (4.98)
6 NW 96.1 (8.55) 0.001 60.5 (8.88) 0.001 95.8 (8.37) 0.041 61.5 (7.94) 0.023
OW 102.0 (8.72) 66.1 (8.00) 99.1 (9.28) 65.0 (8.04)
7 NW 97.1 (8.02) 0.001 62.5 (8.61) 0.001 97.6 (8.30) 0.001 62.8 (8.33) 0.001
OW 103.8 (7.86) 66.6 (9.26) 102.3 (7.86) 68.7 (5.90)
8 NW 99.0 (9.01) 0.001 63.9 (8.60) 0.001 98.4 (9.22) 0.001 63.7 (8.56) 0.512
OW 104.2 (8.53) 67.7 (8.81) 104.5 (9.73) 64.6 (7.69)
9 NW 99.9 (8.34) 0.001 65.6 (8.30) 0.001 101.2 (9.28) 0.001 66.2 (8.44) 0.001
OW 107.7 (7.64) 69.8 (7.47) 107.4 (8.89) 70.3 (6.37)
10 NW 101.6 (8.62) 0.001 67.0 (8.10) 0.001 103.9 (9.73) 0.001 68.3 (8.09) 0.001
OW 108.2 (6.90) 70.5 (7.03) 111.2 (9.69) 71.9 (8.60)
11 NW 102.8 (9.42) 0.001 67.8 (8.21) 0.001 106.9 (9.94) 0.001 69.8 (7.78) 0.001
OW 110.5 (8.60) 72.6 (7.35) 111.9 (9.85) 72.7 (8.28)
12 NW 104.7 (9.84) 0.001 68.5 (8.03) 0.026 109.5 (10.38) 0.001 71.7 (7.62) 0.095
OW 111.6 (9.73) 70.5 (8.41) 114.8 (8.45) 73.2 (7.59)
13 NW 107.5 (11.00) 0.001 68.9 (8.67) 0.035 112.0 (10.47) 0.001 72.6 (7.79) 0.509
OW 114.3 (12.09) 71.2 (8.52) 117.4 (10.78) 73.2 (8.03)
14 NW 110.6 (11.14) 0.001 71.0 (8.20) 0.002 112.9 (10.30) 0.001 73.1 (7.88) 0.002
OW 119.7 (10.83) 74.7 (8.71) 119.3 (10.62) 75.9 (6.97)
15 NW 113.4 (10.94) 0.001 72.8 (8.52) 0.984 114.0 (10.28) 0.001 74.1 (7.86) 0.010
OW 119.6 (9.03) 72.7 (7.55) 121.3 (11.92) 77.4 (8.96)
16 NW 114.6 (11.33) 0.002 73.0 (8.21) 0.169 114.2 (10.58) 0.008 74.3 (7.21) 0.026
OW 124.4 (9.74) 76.1 (7.77) 123.9 (12.80) 77.6 (3.45)
*Overweight includes obese children NW normal weight group (children who are neither overweight nor obese) OW overweight group
TABLE VII. Percentages of different forms of hypertension in children with respect to gender and weight group
Group Normal (n=18 931) Overweight (n=1332) Obese (n=382)
Boys Girls Total Boys Girls Total Boys Girls Total
Hypertension 6.76 13.15 10.10 12.31 23.18 17.34 14.94 24.11 18.32
Systolic hypertension 2.82 7.72 5.38 7.97 17.34 12.31 10.79 21.28 14.66
Systolic pre-hypertension 8.76 11.62 10.25 16.50 16.21 16.37 18.67 23.40 20.42
Diastolic hypertension 4.74 8.02 6.45 6.85 11.18 8.86 7.88 10.64 8.90
Diastolic pre-hypertension 12.16 16.46 14.40 17.20 22.37 19.59 17.84 26.24 20.94
RAJ et al. : OBESITY IN CHILDREN: TIME TRENDS AND RELATIONSHIP WITH HYPERTENSION
292 THE NATIONAL MEDICAL JOURNAL OF INDIA VOL. 20, NO. 6, 2007
and ever-increasing automated transport.
34
The difference in
prevalence and trends of overweight
among rural and urban
schools demonstrated by the study could be due to these influences.
However, it is interesting that there was an upward trend noticeable
in rural schools as well. Lifestyle changes are likely to have a
greater impact on children from affluent backgrounds as suggested
by the observation that the rapid rise in prevalence rates of
overweight was largely limited to private schools.
The prevalence of incident hypertension in normal weight
children in our study was 10.1%. The study limitations did not
permit us to follow up cases of incident hypertension and find out
actual values of persistent hypertension which would have been
much smaller than the quoted figure. This phenomenon of low
prevalence of hypertension on subsequent readings has been
demonstrated previously.
Sorof et al.
35
documented first instance
hypertension as 19%, second instance as 9.5% and third instance
(persistent) as 4.5%.
The relationship of overweight and hypertension was examined
in detail. Hypertension was seen in significantly higher percentages
among overweight children when compared with normal children
(17.34% v. 10.1%). This relationship has been reported by other
studies as well.
12,36–41
Rosner et al.
42
pooled data from 8 large
epidemiological studies. Irrespective of race, gender or age, the
risk of elevated BP was significantly higher for children in the
upper compared with the lower decile of BMI, with an odds ratio
of systolic hypertension ranging from 2.5 to 3.7. Freedman et al.
39
reported that overweight children in the Bogalusa heart study
were 4.5 and 2.4 times as likely to have elevated systolic BP and
diastolic BP, respectively. Studies from India have also shown
similar trends.
12–15
Evidence from prospective studies in Asia suggests that obesity
is directly related to the incidence of hypertension, type 2 diabetes
and hypercholesterolaemia.
26,43
According to WHO, chronic
diseases are the major causes of death in almost all countries
including those in Asia.
1
It is estimated that 70% of these deaths
will occur in developing Asian nations such as China, India,
Pakistan, Cambodia and Viet Nam.
1
Cardiovascular diseases are
responsible for the major share of these deaths due to chronic
diseases.
1
South Asians appear to have worse cardiovascular
disease risk profiles when compared with Caucasian populations
with similar BMI levels.
26,43
Small increases in BMI among them
may translate into a substantial increase in the burden of
cardiovascular diseases. For this reason the trends reported here
are alarming even though the overall proportion of obesity and
overweight children is far lower than that reported in other
studies.
Childhood obesity and related hypertension are issues related
to lifestyle patterns in the population. Even though the situation
discussed is alarming, it provides an excellent opportunity for
prevention of cardiovascular diseases by means of lifestyle
interventions targeted at childhood and adolescent populations,
thereby attempting to reduce morbidity and mortality arising from
these diseases in the future.
Limitations of the study
Our study did not include measurements of waist–hip ratio and
skin-fold thickness. BP readings in 2003 also would have been
useful in understanding the trend. Application of international
reference standards of BMI and hypertension in an Indian setting
may have limitations. We measured incident hypertension;
hypertension can only be confirmed after a minimum of 3 separate
BP measurements demonstrating high BP. As BP was measured
in the field, an element of anxiety and apprehension might have
affected a subset of children in our study. The data provided are
univariate.
Conclusions
Childhood obesity showed a significantly increasing trend in a
short period of 2 years. Hypertension was seen in high percentages
in children with overweight and obesity when compared with
children who were neither overweight nor obese. Unless effective
interventions and preventive strategies are instituted at the local
and national level, these observations suggest that the trend of
increasing cardiovascular disease in adults observed in recent
decades will accelerate even further. These trends are disturbing
and call for concerted efforts targeted at improving lifestyles of
children and adolescents.
ACKNOWLEDGEMENTS
The study was supported by a grant from the Indian Council of Medical
Research. This study was a component of the Jai Vigyan Mission Mode
Project on Rheumatic Fever and Rheumatic Heart Disease.
REFERENCES
1 World Health Organization. Preventing chronic diseases: A vital investment.
World Global Report. Geneva:World Health Organization; 2005.
2 Must A, Jacques PF, Dallal GE, Bajema CJ, Dietz WH. Long-term morbidity and
mortality of overweight adolescents: A follow-up of the Harvard Growth Study of
1922 to 1935. N Engl J Med 1992;327:1350–5.
3 Barlow SE, Dietz WH. Obesity evaluation and treatment: Expert Committee
recommendations. The Maternal and Child Health Bureau, Health Resources and
Services Administration and the Department of Health and Human Services.
Pediatrics 1998;102:E29.
4 Nanda K. Non-alcoholic steatohepatitis in children. Pediatr Transplant 2004;8:
613–18.
5 Li X, Li S, Ulusoy E, Chen W, Srinivasan SR, Berenson GS. Childhood adiposity
as a predictor of cardiac mass in adulthood: The Bogalusa Heart Study. Circulation
2004;110:3488–92.
6 Ogden CL, Troiano RP, Briefel RR, Kuczmarski RJ, Flegal KM, Johnson CL.
Prevalence of overweight among preschool children in the United States, 1971
through 1994. Pediatrics 1997;99:E1.
7 Chhatwal J, Verma M, Riar SK. Obesity among pre-adolescent and adolescents of
a developing country (India). Asia Pac J Clin Nutr 2004;13:231–5.
8 Ramachandran A, Snehalatha C, Vinitha R, Thayyil M, Kumar CK, Sheeba L, et al.
Prevalence of overweight in urban Indian adolescent school children. Diabetes Res
Clin Pract 2002;57:185–90.
9 Marwaha RK, Tandon N, Singh Y, Aggarwal R, Grewal K, Mani K. A study of
growth parameters and prevalence of overweight and obesity in school children
from Delhi. Indian Pediatr 2006;43:943–52.
10 Khadilkar VV, Khadilkar AV. Prevalence of obesity in affluent school boys in
Pune. Indian Pediatr 2004;41:857–8.
11 Kapil U, Singh P, Pathak P, Dwivedi SN, Bhasin S. Prevalence of obesity amongst
affluent adolescent school children in Delhi. Indian Pediatr 2002;39:449–52.
12 Verma M, Chhatwal J, George SM. Obesity and hypertension in children. Indian
Pediatr 1994;31:1065–9.
13 Mohan B, Kumar N, Aslam N, Rangbulla A, Kumbkarni S, Sood NK, et al.
Prevalence of sustained hypertension and obesity in urban and rural school going
children in Ludhiana. Indian Heart J 2004;56:310–4.
14 Anand NK, Tandon L. Prevalence of hypertension in school going children. Indian
Pediatr 1996;33:377–81.
15 Gupta AK, Ahmad AJ. Childhood obesity and hypertension. Indian Pediatr
1990;27:333–7.
16 Department of Health and Human Services. Centers for Disease Control and
Prevention, USA. CDC growth charts for the United States [database on the
internet]. Available at http://www.cdc.gov/nchs/data/nhanes/growthcharts/zscore/
bmiagerev.xls (accessed on 12 January 2007).
17 National High Blood Pressure Education Program Working Group on High Blood
Pressure in Children and Adolescents. The fourth report on the diagnosis, evaluation,
and treatment of high blood pressure in children and adolescents. Pediatrics
2004;114:555–76.
18 Woodward M. Epidemiology: Study design and data analysis. 2nd edn.
London:Chapman Hall/CRC; 2005.
19 Kotchen JM, Kotchen TA, Guthrie GP Jr, Cottrill CM, McKean HE. Correlates of
adolescent blood pressure at five-year follow-up. Hypertension 1980;2:124–9.
20 Clarke WR, Woolson RF, Lauer RM. Changes in ponderosity and blood pressure
in childhood: The Muscatine Study. Am J Epidemiol 1986;124:195–206.
293
RAJ et al. : OBESITY IN CHILDREN: TIME TRENDS AND RELATIONSHIP WITH HYPERTENSION
21 Johnson AL, Cornoni JC, Cassel JC, Tyroler HA, Heyden S, Hames CG. Influence
of race, sex and weight on blood pressure behavior in young adults. Am J Cardiol
1975;35:523–30.
22 Gidding SS, Bao W, Srinivasan SR, Berenson GS. Effects of secular trends in
obesity on coronary risk factors in children: The Bogalusa Heart Study. J Pediatr
1995;127:868–74.
23 Morrison JA, Laskarzewski PM, Rauh JL, Brookman R, Mellies M, Frazer M, et
al. Lipids, lipoproteins, and sexual maturation during adolescence: The Princeton
maturation study. Metabolism 1979;28:641–9.
24 Higgins MW, Keller JB, Metzner HL, Moore FE, Ostrander LD Jr. Studies of blood
pressure in Tecumseh, Michigan. II. Antecedents in childhood of high blood
pressure in young adults. Hypertension 1980;2 (Suppl 1):117–23.
25 Ge K. Body mass index of young Chinese adults. Asia Pac J Clin Nutr 1997;6:
175–9.
26 Ko GT, Chan JC, Woo J, Lau E, Yeung VT, Chow CC, et al. Simple anthropometric
indexes and cardiovascular risk factors in Chinese. Int J Obes Relat Metab Disord
1997;21:995–1001.
27 Yoshiike N, Matsumura Y, Zaman MM, Yamaguchi M. Descriptive epidemiology
of body mass index in Japanese adults in a representative sample from the National
Nutrition Survey 1990–1994. Int J Obes Relat Metab Disord 1998;22:684–7.
28 Aekplakorn W, Chaiyapong Y, Neal B, Chariyalertsak S, Kunanusont C,
Phoolcharoen W, et al. Prevalence and determinants of overweight and obesity in
Thai adults: Results of the Second National Health Examination Survey. J Med
Assoc Thai 2004;87:685–93.
29 Griffiths PL, Bentley ME. The nutrition transition is underway in India. J Nutr
2001;131:2692–700.
30 Chu NF. Prevalence of obesity in Taiwan. Obes Rev 2005;6:271–4.
31 Wu Y. Overweight and obesity in China. BMJ 2006;333:362–3.
32 World Health Organization. Diet, nutrition and prevention of chronic diseases.
Geneva:WHO; 2003.
33 Popkin BM, Doak CM. The obesity epidemic is a worldwide phenomenon. Nutr
Rev 1998;56:106–14.
34 Bar-Or O, Foreyt J, Bouchard C, Brownell KD, Dietz WH, Ravussin E, et al.
Physical activity, genetic, and nutritional considerations in childhood weight
management. Med Sci Sports Exerc 1998;30:2–10.
35 Sorof JM, Lai D, Turner J, Poffenbarger T, Portman RJ. Overweight, ethnicity, and the
prevalence of hypertension in school-aged children. Pediatrics 2004;113:475–82.
36 Elcarte Lopez R, Villa Elizaga I, Sada Goni J, Gasco Eguiluz M, Oyarzabal
Irigoyen M, Sola Mateos A, et al. The Navarra study. Prevalence of arterial
hypertension, hyperlipidemia and obesity in the infant–child population of Navarra.
Association of risk factors. An Esp Pediatr 1993;38:428–36.
37 Guillaume M, Lapidus L, Beckers F, Lambert A, Bjorntorp P. Cardiovascular risk
factors in children from the Belgian province of Luxembourg. The Belgian
Luxembourg Child Study. Am J Epidemiol 1996;144:867–80.
38 Macedo ME, Trigueiros D, de Freitas F. Prevalence of high blood pressure in
children and adolescents. Influence of obesity. Rev Port Cardiol 1997;16:27–8.
39 Freedman DS, Dietz WH, Srinivasan SR, Berenson GS. The relation of overweight
to cardiovascular risk factors among children and adolescents: The Bogalusa Heart
Study. Pediatrics 1999;103:1175–82.
40 Morrison JA, Barton BA, Biro FM, Daniels SR, Sprecher DL. Overweight, fat
patterning, and cardiovascular disease risk factors in black and white boys. J
Pediatr 1999;135:451–7.
41 Sorof JM, Poffenbarger T, Franco K, Bernard L, Portman RJ. Isolated systolic
hypertension, obesity, and hyperkinetic hemodynamic states in children. J Pediatr
2002;140:660–6.
42 Rosner B, Prineas R, Daniels SR, Loggie J. Blood pressure differences between
blacks and whites in relation to body size among US children and adolescents. Am
J Epidemiol 2000;151:1007–19.
43 Oh SW, Shin SA, Yun YH, Yoo T, Huh BY. Cut-off point of BMI and obesity-
related comorbidities and mortality in middle-aged Koreans. Obes Res
2004;12:2031–40.
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    • "Lack of physical activity and change in dietary pattern are indicated as two major reasons for obesity in children (Misra et al., 2011). Provision of properly distributed, accessible (within walking distances), safe and properly maintained UGS can encourage urban residents to take up physical activity and in turn enable them to ward off many health related risks (Raj et al., 2007). It is to be noted that this is the situation in the NCT Delhi, which is the capital of India and ranks among the greenest cities of the world. "
    [Show abstract] [Hide abstract] ABSTRACT: The accessibility to hierarchy (defined based on function and size) of Urban Green Spaces (UGS) is essential for frequent and optimal use of UGS as it promotes social interaction and physical activity among city population. The issue of accessibility to UGS is one of the crucial aspects of sustainable urban planning and it is linked to growing concern over the wellbeing of urban population particularly children and lower socioeconomic groups. The following study presents use of GIS based network analysis to assess the accessibility of UGS at hierarchical levels by applying different network distance to each hierarchy of UGS in a dense and complex urban setting in a developing region. Results show that there is poor accessibility to UGS at all hierarchical levels particularly at lower hierarchy of UGS which is meant for early age children. The large variability in accessibility at all hierarchical levels is also indicative of highly varying and skewed development patterns in the study area. The studies carried out in these regions and approach applied in this study may provide useful tools to planners to identify the deficient areas for future development of UGS for balanced and sustainable planning.
    Full-text · Article · Jun 2016
    • "A European pediatric cohort showed that high BP was seen in about 35% of overweight children [17]. In another recent study [18] that covered 26,000 school children, the systolic hypertension observed was 5.3%, 12.3% and 14.6% for normal, overweight and obese children, respectively. High levels of hypertension reported in other studies from Greece should be under serious concern. "
    [Show abstract] [Hide abstract] ABSTRACT: Background The worldwide prevalence of childhood obesity has increased from 4.2% to 6.7% during the last two decades. Pediatric obesity is a major health problem, which is dramatically increasing in Greece. A variety of inflammatory variables have been also found to associate with cardiometabolic (CV) risk in obese children. The purpose of this study was to identify and examine the effects of possible CV risk factors in obese and non-obese children with and without family history (FH) of cardiovascular disease (CVD). Methods Sixty-eight (68) healthy children and adolescents aged 7 - 13 years participated in the study. Anthropometrical and biochemical indexes were obtained from all children as well as FH of CVD. Results Systolic blood pressure (SBP), total cholesterol (TC), triglyceride (TG), high-sensitivity C-reactive protein (hsCRP), fasting plasma insulin (FPI) and homeostasis model assessment of insulin resistance (HOMA-IR) levels were found statistically significantly higher in the obese group compared to the non-obese one. High-density lipoprotein (HDL) levels were observed to be statistically significantly lower in the obese children compared to their normal peers. Conclusions Apolipoprotein A, hsCRP and FPI levels were significantly higher in the obese children with FH of CVD compared to the ones without FH of CVD. TC and SBP were found to be independently associated with obesity (odds ratio (OR): 1.965, 95% confidence interval (CI): 1.935 - 2.97, P < 0.031 and OR: 1.045, 95% CI: 1.016 - 1.074, P < 0.002, respectively).
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    • "Systematic review shows that globally the prevalence of overweight varies between 4.6 to 25.9% and the prevalence of obesity ranges between 2.7 to 20.1% [1]. Reports from various regional studies conducted in India showed that the prevalence of childhood obesity ranged between 7-20% across the country234. Excess calorie intake and reduced physical activity are more rampant among Indian children and this feature accelerates the rate of obesity in children [5]. "
    Full-text · Article · Jan 2016 · Journal of Clinical Medicine Research
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