Assessment of risk factors for hypertension and obesity among adolescents

Introduction: The rising trend of noncommunicable diseases (NCDs) globally and their associated mortality and morbidity, with a shift to the younger population is a matter of concern. Objective: To study the risk factors for hypertension and obesity among adolescents Design and setting: Hospital based cross sectional study in the paediatric outpatient department (OPD) of a tertiary care hospital. Subjects: Adolescents in the age group 10-18 years presenting to the paediatric OPD from 13 January 2013 to 14 December 2014. Results: There were 218 such adolescents of whom 51% were female. Of the 218, 37% had a family history (F/H) of hypertension, 27% a F/H of diabetes mellitus, 17% a F/H of obesity, 17% a F/H of cardiovascular diseases and 4% a F/H of cerebrovascular accidents. There was a history of passive smoking in 41%, consumption of aerated drinks in 73% and fast food consumption in 92%. Tobacco consumption was recorded in 1.8% and alcohol consumption in 2.9%. Fifteen (6.9%) subjects were found to be overweight and one (0.4%) subject was obese. Twenty two (10%) had systolic hypertension and 23 (10.5%) diastolic hypertension. BMI had a significant correlation with systolic and diastolic hypertension. Conclusions: Fast food consumption was present in 92% of adolescents and physical activity with duration less than 30 minutes in 44.5% of adolescents in this study. BMI was significantly associated with both systolic and diastolic hypertension in this study. DOI: http://dx.doi.org/10.4038/sljch.v46i1.8120 ________________________________________ Sri Guru Ramdas Institute of Medical Sciences & Research (SGRDIMSR), Amritsar, India *Correspondence: dr.sunita1@yahoo.com (Received on 10 May 2016: Accepted after revision on 17 June 2016) The authors declare that there are no conflicts of interest Personal funding was used in formulating the article. Open Access Article published under the Creative Commons Attribution CC-BY License. (


Introduction
Non-communicable diseases (NCDs) such as diabetes, hypertension, cardiovascular diseases, stroke, obesity, dyslipidaemia and malignancy account for 60% of deaths and 47% of the global burden of disease 1 .Prevalence of childhood hypertension is noted to be 5-10% in developing countries and 1-2% in developed countries 2 .In India, adolescents account for almost 20% of its population 3 .Risk factors like fast food consumption, low physical activity, high level of experimentation with alcohol and smoking have led to a high prevalence of obesity and hypertension in adolescents 4 .All these risk factors are preventable and modifiable.
Moderate to vigorous physical activity like brisk walking, dancing, swimming or cycling, if done regularly (≥3 times per week) decreases risk of NCDs by weight loss, reduction of visceral fat with lowering of blood pressure and improved glucose control by increased insulin sensitivity 5 .Tobacco use among adolescents can be initiated by its use by elders in the family, peer influence, experimentation, underlying emotional and psychological factors, risk taking behaviour and aggressive marketing stratergies 6 .Family history of hypertension is an important non modifiable risk factor for hypertension 7 .Having a parent with noninsulin dependent diabetes mellitus (NIDDM) increases two to fourfold an offspring's chance of developing this condition 8 .

Objectives
To study the risk factors for hypertension and obesity among adolescents.

Method
This study was conducted in the paediatric outpatient department (OPD) of Sri Guru Ramdas Institute of Medical Sciences & Research (SGRDIMSR), Amritsar, a tertiary care centre in India, from 13 th January 2013 to 14 th December 2014.Adolescents aged 10-18 years attending paediatric OPD during the study period, after taking informed consent from their parents or guardian, were enrolled.Study was approved by the Ethics Committee of SGRDIMSR.Children suffering from chronic cardiovascular, respiratory, endocrine, musculoskeletal and renal disorders, obesity due to hereditary, genetic and metabolic disorders and children on medication known to affect blood pressure were excluded from the study.
It was a cross sectional hospital based study.A pretested structured, close ended questionnaire was used for data collection after explaining in vernacular language.Questionnaire sought information regarding demographic details, dietary practices, physical activity, time spent on television, video games, computer, history of smoking, family history of hypertension, diabetes, obesity, stroke or malignancy in parents.Weight was recorded with minimal permissible clothes with accurate standard electronic weighing scale with a precision of ±10 grams.Height was measured with stadiometer to the nearest 0.1 cm.BMI was calculated using the formula weight (kg) /height (m 2 ).According to CDC 2000, BMI for gender and age >85 th percentile was considered overweight and BMI >95 th percentile was considered obese 9 .Blood pressure was recorded in the right arm in the sitting position with appropriate cuff size by auscultatory method with sphygmomanometer.Sufficient time was given to allay anxiety and fear.First and fifth phases of Korotkoff sounds was taken as systolic and diastolic blood pressure.Two more measurements were taken at 15 and 30 minutes and mean of three readings was taken as final observation.BP was classified as normal, prehypertension, stage 1 and stage 2 hypertension with respect to age, sex and height percentile 10 .
Observations were expressed as frequency distribution.Statistical significance was evaluated using Pearson's Chi-square and, Student's t-test.Comparison of mean BMI across stages of SBP and DBP was carried out by using one way ANOVA.All analysis were performed using SPSS 18.0 (SPSS Inc) software and statistical significance was evaluated at 5% value.

Results
Two hundred and eighteen adolescents in the age group 10-18 years were enrolled for the study.Of them 107 (49%) were male and 111 (51%) were female.One hundred and fifty three (70%) were in the 10-14 year age group.Males outnumbered females in 10-14 year age category whereas females outnumbered males in the over 14 year age category.Majority of participants were of normal stature but 37% had short stature.Whilst 78% of participants had a normal BMI, around 15% were underweight and 07% were overweight.Distribution of age, stature and BMI according to gender is shown in Table 1.Distribution of participants according to risk factors and risk score within family is shown in Table 2. Family history of passive smoking, hypertension and diabetes mellitus were the 3 most common risk factors (Table 1).Forty six (21%) had no family history of risk factors and a risk score of zero.
Whilst 76 (35%) of the participants had a risk score of one, 96 (44%) had risk scores ranging from 2 to 5. Distribution of participants according to physical activity and dietary habits is shown in Table 3. Family history of obesity and skipping of meals were not significantly associated with BMI.Mean duration of physical activity was significantly higher in those with lower BMI (p<0.05).
Consumption of fast food did not have a significant correlation with BMI.Distribution of participants according to systolic and diastolic blood pressure is shown in Table 5. Majority of the subjects had normal systolic and diastolic blood pressures.Females outnumbered males in stage 1 and 2 systolic hypertension.The distribution of participants in relation to systolic BP stages between two genders was statistically significant.Difference of diastolic BP between males and females was not statistically significant.The association of systolic/diastolic BP with BMI, risk score and physical activity is shown in Table 6.Systolic and diastolic BP did not show a significant association with risk score categories using Pearson's Chi square test resulting in p values of 0.436 and 0.691 respectively.Systolic and diastolic BP did not show a significant association with type of physical activity (indoor or outdoor) resulting in p values of 0.288 and 0.083 respectively.Table 7 shows SBP/DBP categories according to BMI, diet and family history of hypertension.Obtained using Chi square test SBP: Systolic blood pressure DBP: Diastolic blood pressure BMI: Body mass index HT: Hypertension BMI centile showed a highly significant association with various stages of SBP and DBP.Association of SBP with type of diet was significant whereas the association of DBP with type of diet was not significant.No statistically significant association was observed between family history of hypertension and SBP/DBP.

Discussion
Increasing prevalence of NCDs due to rapid urbanisation and globalisation in India is a cause of great concern.A rising trend is being observed in adolescents with its serious consequences in future adulthood.It is pertinent to investigate preventable risk factors in order to implement integrated preventive strategies.
Gender distribution of 218 adolescents enrolled in the present study was almost equal and 153 (70%) were in 10-14 year age group.Similar gender distribution was observed by SV Mane et al in 2012 11 .AK Singh et al and Ali Khuwaja et al observed slight preponderance of boys 4,12 .One hundred and twenty one subjects fulfilled the requirement of physical activity of more than 30 minutes as per WHO recommendations and there was no significant difference in males and females.Shah et al in 2005 in a study done across 81 regions of India showed inactivity levels as 12.6% in males and 18.9% in females 13 4,14 .No significant association was found between a F/H of hypertension and BP profile of adolescents in the present study.
Joshi H et al 2014 reported that 23.5% adolescents consumed junk food twice or more per week 15 .In the study by Rani et al 2013, 85% students reported eating fast food with 22% eating it for more than three days a week 16 .In our study 200 (91.7%)adolescents consumed fast food with a frequency of 3-6 times per week in 57.5% and daily consumption in 42.5%.A matter of grave concern was that fast food consumption was in addition to their regular meals in 145 out of 218 adolescents in the present study.In the present study, 106 (53%) girls had a history of fast food consumption compared with 94 (47%) boys.Ranjit et al 2010 and Vereecken et al 2005 made observations to the contrary 17,18 .Smoking prevalence has varied from 8.8% to 13.1% in different studies 19 .Tobacco consumption was low (1.8%) in the present study.Alcohol consumption was recorded in 2.9% in our study.A higher prevalence (7.4%) was reported by Tsering et al in 2010 20 .
Overweight and obesity was found in 3.1% and 2.1% respectively by Bharati et al 2008 21 .Out of 218 adolescents, 15 subjects (6.88%) were found to be overweight with equal distribution among both genders.Only 1 subject (0.4%) was obese.Chandla et al in 2009 revealed similar prevalence as was found in present study 22 .Laxmaiah A et al 2007 reported higher prevalence in females (8.2%) as compared to males (6.1%) 23 .A higher prevalence of overweight and obesity was reported by AK Singh et al 2006 (18.6% boys and 16.5% girls) 4 .Lack of correlation of fast food consumption and obesity in present study was probably because duration of physical activity as recommended by WHO was fulfilled by half of the study population.
Out of 218 subjects, 22 (10%) had systolic hypertension.Females outnumbered males (18 vs 4) and the difference was statistically significant.Diastolic hypertension was detected in 23 subjects (10.5%) but gender difference was not significant.Prevalence of hypertension of 8.5% has been reported by Demirci H et al 2013 24 , 5.4% by Patel et al 2014 25 , 9.78% by Khan M et al 2010 13 and 10.91% by Borade et al 2011 26 .Durrani et al 2011 found lower prevalence of hypertension in boys (9.36%) as compared to girls (9.4%) 27 .Lower prevalence in females (11.76%) has been reported as compared to boys (13.79%) by Lone et al 2015 28 .Association between systolic and diastolic hypertension and family history of hypertension was not statistically significant in present study.However AK Singh et al 2006 highlighted such association in their study 4 .Family history of obesity which was present in 37% of subjects was not statistically significant in relation to both systolic and diastolic hypertension in present study.BMI had a statistically significant correlation with SBP/DBP.Systolic Prehypertension was found in 10 (4.5%) and diastolic prehypertension was found in 17 (7.75%)subjects.Similar observations were made by Patel et al in 2014 25 .Higher prevalence of 15.7% and 24.5% was reported by Mc Niece KL et al 2007 and Madhavikutty Amma GD et al 2015 29,30 .AK Singh et al 2006 found more prevalence in males (11.82%) than females (3%) and overall prevalence of systolic hypertension was lower (7.84%) 4 .High prevalence of isolated systolic hypertension (37.4%) was reported by Khan M I et al 2010 14 .

Conclusions
• Fast food consumption was present in 92% of adolescents in this study.
• Physical activity with duration less than 30 minutes was present in 44.5% of adolescents in this study.• Systolic and diastolic hypertension were detected in 10% and 10.5% subjects respectively.• BMI was significantly associated with both systolic and diastolic hypertension in this study.

Table 7 : SBP/DBP categories according to BMI, diet and family history of hypertension
. SV Mane et al in 2012 observed a F/H of diabetes in 30% adolescents, a F/H of hypertension in 26.5% and a F/H of heart diseases and obesity in 20.5% each 11 .AK Singh et al in 2006 reported a F/H of hypertension in 50% each of boys and girls and a F/H of obesity in 23% of boys and 30% of girls 4 .In the present study, 37% had a family history (F/H) of hypertension, 27% had a F/H of diabetes mellitus, 17% a F/H of obesity, 17% a F/H of cardiovascular disease and 4% a F/H of cerebrovascular accidents.AK Singh et al in 2006 and Khan H et al in 2010 reported a positive correlation of hypertension in those adolescents who had positive F/H of hypertension