Television Viewing and Hypertension in Obese Children

      Background

      Television viewing is strongly associated with an increased risk of childhood and adolescent obesity. However, the association between TV viewing and hypertension in children is unknown. This study aimed to identify whether TV watching is associated with hypertension in obese children.

      Methods

      Children seen for obesity, aged 4 to 17 years, were evaluated at three pediatric centers from 2003 to 2005. In 2006–2007, a logistic regression model estimated the odds of hypertension for hours of daily TV time controlling for race, site, and body mass index (BMI) z-score.

      Results

      A total of 546 subjects, with a mean age of 12 years, were evaluated. The children had a mean BMI of 35.5±9.3 kg/m2 (98.7th±0.8 percentile, z-score 2.54±0.4). TV time was positively correlated with the severity of obesity. After controlling for race, site, and BMI z-score, both the severity of obesity and daily TV time were significant independent predictors of the presence of hypertension. Children watching 2 to 4 hours of TV had 2.5 times the odds of hypertension compared with children watching 0 to <2 hours. The odds of hypertension for children watching 4 or more hours of TV were 3.3 times greater than for children watching 0 to <2 hours of TV.

      Conclusions

      In obese children, the amount of time spent watching TV is associated with both hypertension and the severity of obesity. Thus, TV viewing is a potential target for addressing hypertension in obese children.

      Introduction

      Childhood obesity is a major health concern in the United States. As of 2004, the National Health and Nutrition Examination Survey (NHANES) estimated that 17% of children and adolescents were obese.
      • Ogden C.L.
      • Carroll M.D.
      • Curtin L.R.
      • McDowell M.A.
      • Tabak C.J.
      • Flegal K.M.
      Prevalence of overweight and obesity in the United States, 1999–2004.
      Obesity is known to increase the possibility of cardiovascular risk factors, such as hypertension.
      • Wilson P.W.
      • D’Agostino R.B.
      • Sullivan L.
      • Parise H.
      • Kannel W.B.
      Overweight and obesity as determinants of cardiovascular risk: the Framingham experience.
      Recent studies have shown that cardiovascular risk factors in childhood are significant predictors of preclinical atherosclerosis in adulthood.
      • Raitakari O.T.
      • Juonala M.
      • Kahonen M.
      • et al.
      Cardiovascular risk factors in childhood and carotid artery intima-media thickness in adulthood: the Cardiovascular Risk in Young Finns study.
      Thus, the increased prevalence of elevated systolic and diastolic blood pressures among U.S. youth over the past 10 years is cause for concern.
      • Muntner P.
      • He J.
      • Cutler J.A.
      • Wildman R.P.
      • Whelton P.K.
      Trends in blood pressure among children and adolescents.
      The upward shift of blood pressure in children persists after controlling for population changes in body mass index (BMI).
      • Muntner P.
      • He J.
      • Cutler J.A.
      • Wildman R.P.
      • Whelton P.K.
      Trends in blood pressure among children and adolescents.
      Therefore, studies are warranted to assess the contribution of other factors to hypertension in overweight children and adolescents.
      Numerous studies
      • Anderson R.E.
      • Crespo C.J.
      • Bartlett S.J.
      • Cheskin L.J.
      • Pratt M.
      Relationship of physical activity and television watching with body weight and level of fatness among children: Results from the third national Health and Nutrition Examination survey.
      • Eisenmann J.C.
      • Bartee R.T.
      • Wang M.Q.
      Physical activity, TV viewing, and weight in U.S. youth: 1999 Youth Risk Behavior survey.
      • Dietz W.H.
      • Gortmaker S.L.
      Do we fatten our children at the TV set? Obesity and television in children and adolescents.
      • Gortmaker S.L.
      • Must A.
      • Sobol A.M.
      • Peterson K.
      • Colditz G.A.
      • Dietz W.H.
      Television viewing as a cause of increasing obesity among children in the United States, 1986–1990.
      • Angelopoulos P.D.
      • Milionis H.J.
      • Moschonis G.
      • Manios Y.
      Relations between obesity and hypertension: preliminary data from a cross-sectional study in primary schoolchildren: the children study.
      • Marshall S.J.
      • Biddle S.J.H.
      • Gorely T.
      • Cameron N.
      • Murdey I.
      Relationships between media use, body fatness and physical activity in children and youth: a meta analysis.
      • Guillaume M.
      • Lapidus L.
      • Bjorntorp P.
      • Lambert A.
      Physical activity, obesity, and cardiovascular risk factors in children The Belgian Luxembourg Child Study II.
      • Hernandez B.
      • Gortmaker S.L.
      • Colditz G.A.
      • Peterson K.E.
      • Laird N.M.
      • Parra-Cabrera S.
      Association of obesity with physical activity, television programs and other forms of video viewing among children in Mexico City.
      have shown that time spent watching TV is strongly associated with the risk of being obese in children and adolescents. However, the majority of research has been population-based, which focuses on the risk of being obese versus normal-weight. Little attention has been given to the issue of how TV time is associated with the severity of obesity in obese children. The growing number of obese children worldwide indicates the importance of studying obesity-related issues within this group. Research focusing on an obese population may assist in further identifying prevention and treatment measures for obese children. In addition to the paucity of information available regarding TV time and the severity of obesity, little to no information exists regarding hypertension and TV viewing in obese children. One recent European study did not find an association between TV watching and blood pressure among children
      • Angelopoulos P.D.
      • Milionis H.J.
      • Moschonis G.
      • Manios Y.
      Relations between obesity and hypertension: preliminary data from a cross-sectional study in primary schoolchildren: the children study.
      ; another found a small association between systolic blood pressure and TV time in boys, but no association in girls.
      • Guillaume M.
      • Lapidus L.
      • Bjorntorp P.
      • Lambert A.
      Physical activity, obesity, and cardiovascular risk factors in children The Belgian Luxembourg Child Study II.
      However, neither of these studies examined the association between TV viewing and blood pressure among obese children. The current study tested the hypothesis that time spent watching TV is associated with hypertension in obese children.
      See related Commentary on page 502.

      Methods

      Participants

      Subjects were children, aged 4 to 17 years, evaluated for obesity at pediatric subspecialty weight management clinics in San Diego CA, San Francisco CA, and Dayton OH, from 2003 to 2005. Data were collected prospectively, with written consent obtained from all parents, and written assent from children aged 8 years and older. Obesity, defined as a BMI greater than or equal to the 95th percentile for age and gender, was an inclusion criterion. Children with a pre-existing diagnosis of hypertension requiring medication or secondary hypertension were not included in the data collection. The research protocols were approved by the institutional review boards of the University of California, San Diego; Rady Children’s Hospital, San Diego; University of California, San Francisco; and Dayton Children’s Hospital, Dayton, Ohio.

      Clinical Data Collection

      Databases were reviewed for information on age, gender, race, ethnicity, height, weight, systolic blood pressure, and diastolic blood pressure. The child’s height was measured to the nearest tenth of a centimeter using a clinical stadiometer. Weight was measured on a clinical scale to the nearest tenth of a kilogram. After 3 minutes of seated rest, blood pressure was measured twice from the right arm of the seated child using an automated sphygmomanometer, with 1 minute of rest between measurements. The average of the two measures was recorded. Cuff sizes were selected according to the circumference of the mid-upper arm, per standard protocol.
      • Perloff D.
      • Grim C.
      • Flack J.
      • et al.
      Human blood pressure determination by sphygmomanometry.
      Children and their parent(s) were given a written questionnaire, which was filled out by the parent(s) only if the child was aged less than 8 years, and both parent and child together if the child was between the ages of 8 and 17 years. If completed by parent and child together, they were instructed to agree on and record a single estimate of average daily time spent watching TV. Parent estimates of child viewing time have been shown to be reliable predictors of child screen time.
      • Anderson D.R.
      • Field D.E.
      • Collins P.A.
      • Lorch E.P.
      • Nathan J.G.
      Estimates of young children’s time with television: a methodological comparison of parent reports with time-lapse video home observation.
      Previous research has shown high retest reliability of child self-reported TV-viewing time estimates.
      • Robinson T.N.
      • Killen J.D.
      Ethnic and gender differences in the relationships between television viewing and obesity, physical activity and dietary fat intake.
      In order to further ensure the validity of TV-viewing time estimates, the physician verbally reviewed and confirmed the time estimate obtained from the questionnaire during the clinical interview with the parent(s) and, if aged over 8 years, the child.

      Clinical Data Calculations

      Blood pressure measurements were converted to percentiles using the National High Blood Pressure Education Program tables, with hypertension defined as a systolic and/or diastolic blood pressure greater than or equal to the 95th percentile for the child’s age, gender, and height.
      National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents
      The fourth report on diagnosis, evaluation, and treatment of high blood pressure in children and adolescents.
      BMI was calculated by dividing the weight of the child in kilograms by the height in meters squared. BMI percentiles and z-scores were determined from the Centers for Disease Control and Prevention (CDC) 2000 growth curves.
      • Kuczmarski R.J.
      • Ogden C.L.
      • Grummer-Strawn L.M.
      CDC growth charts: United States advance data from vital and health statistics.
      A z-score is the number of standard deviations the subject’s BMI lies from the national reference mean for a given age and gender.

      Data Analysis

      Data were analyzed in 2006. Ranges, percentiles, standard deviations, and means were calculated for clinical and demographic variables. The association between hours of TV watched and the severity of obesity was determined with the Pearson correlation, with severe obesity defined as a BMI ≥99th percentile. Differences in BMI, BMI z-score, BMI percentile, age, and hours of TV/day between children with and without hypertension were tested with t tests. Differences in the proportion with hypertension between boys and girls and race/ethnicity groups were tested with chi-square tests.
      A multivariate logistic regression model estimated the odds ratios (ORs) and 95% confidence intervals (CIs) with hypertension as the dependent variable, and hours of daily TV time (0 to <2 hours, 2 to <4 hours, ≥4 hours) and BMI z-score as independent variables, with additional covariates of race and site. All reported p-values were for two-sided tests, with effects considered statistically significant at p<0.05. All statistical analyses were performed using SPSS software, version 15.0.

      Results

      Study Sample

      A total of 556 children from three pediatric subspecialty centers met the inclusion criteria for the study. Ten children with missing data were excluded from the analysis. The demographic and clinical characteristics of the remaining 546 subjects (275 boys, 271 girls) are described in Table 1. The mean age for the sample was 11.9 years. The mean BMI was 35.5±9.3 kg/m2 (98.7th±0.8 percentile, z-score=2.54±0.4). Table 1 also shows the distribution of children within the TV-time categories. The majority of children (78%) watched ≥2 hours of TV per day. Mean time spent watching TV (3.2±1.8 hours per day) was similar to population norms.
      • Eisenmann J.C.
      • Bartee R.T.
      • Wang M.Q.
      Physical activity, TV viewing, and weight in U.S. youth: 1999 Youth Risk Behavior survey.
      Overall, children in the 0- to <2-hour category watched a mean of 1.0±0.4 hours of TV per day; in the 2- to <4-hour category, 2.4±0.5 hours per day; in the 4+-hours category, 5.0±1.0 hours per day.
      Table 1Clinical and demographic characteristics of the study population
      CharacteristicAll subjects (N=546)Subjects without hypertension (n=311)Subjects with hypertension (n=235)
      Age, mean (SD), years
      p<0.05 for children with hypertension versus without hypertension.
      11.9 (3.4)11.7 (3.5)12.3 (3.3)
      Gender, N (%)
       Male275 (50.4)160 (51.4)115 (48.9)
       Female271 (49.6)151 (48.6)120 (51.1)
      Race/ethnicity, N (%)
       African American127 (23.3)64 (20.6)63 (26.8)
       Asian/Pacific Islander20 (3.7)12 (3.9)8 (3.4)
       Hispanic37 (6.8)23 (7.4)14 (6.0)
       Multiracial21 (3.8)15 (4.8)6 (2.6)
       White287 (52.6)159 (51.1)128 (54.5)
       Other54 (9.9)38 (12.2)16 (6.8)
      Blood pressure (mm Hg)
       Systolic (mean, SD)
      p<0.05 for children with hypertension versus without hypertension.
      121.0 (16.1)110.6 (10.4)134.7 (11.2)
       Diastolic (mean, SD)
      p<0.05 for children with hypertension versus without hypertension.
      65.3 (9.5)61.9 (8.4)69.8 (8.9)
      BMI (kg/m2)
       Mean (SD)
      p<0.05 for children with hypertension versus without hypertension.
      35.5 (9.3)33.9 (8.5)37.6 (9.8)
       Percentile, mean (SD)
      p<0.05 for children with hypertension versus without hypertension.
      98.7 (0.8)98.6 (0.9)98.9 (0.5)
       Z-score, mean (SD)
      p<0.05 for children with hypertension versus without hypertension.
      2.54 (0.4)2.49 (0.5)2.59 (0.4)
      Hours of TV/day, Mean (SD)
      p<0.05 for children with hypertension versus without hypertension.
      3.1 (1.8)2.8 (1.7)3.6 (1.8)
      TV time categories, N (%)
       0 to <2 hours/day121 (22.2)94 (30.2)27 (11.5)
       2 to <4 hours/day202 (37.0)115 (37.0)87 (37.0)
       ≥4 hours/day223 (40.8)102 (32.8)121 (51.5)
      BMI, body mass index.
      a p<0.05 for children with hypertension versus without hypertension.

      TV and Obesity

      There was a positive correlation (r=0.17; p<0.001) between time spent watching TV and BMI z-score. When the 99th percentile for BMI was used as a cutpoint, those with a BMI <99th percentile watched 2.6±1.8 hours of TV per day, compared to children with a BMI ≥99th percentile, who watched 3.3±1.7 hours per day (p<0.001). Age, gender, race, and ethnicity were not significantly different between the two groups.

      TV and Hypertension

      As shown in Table 1, hypertension was common in the study sample (235/546, 43%). Children with hypertension had a higher mean BMI than those without hypertension (37.6±9.8 kg/m2 vs 33.9±8.5 kg/m2, p<0.05). The mean age of the group with elevated blood pressure was higher than those without (12.3±3.3 years vs 11.7±3.5 years), and those with hypertension watched nearly 1 hour more TV per day. As shown in Table 1, the majority (89%) of obese children with hypertension watched ≥2 hours of TV per day.
      In unadjusted analysis, greater amounts of daily TV watching were associated with increased odds of hypertension, as shown in Table 2. After controlling for race, site, and BMI z-score, the odds of having hypertension decreased only slightly, indicating that TV viewing is associated with hypertension independent of obesity. In the adjusted analysis, children watching 2 to <4 hours of TV had 2.5 times higher odds of having hypertension than those watching <2 hours. Children viewing ≥4 hours of TV per day had 3.3 times higher odds of having hypertension than those watching <2 hours. BMI z-score also was associated with hypertension (OR=1.62; p=0.029). When TV viewing time was entered into the model as a continuous variable, the odds of having hypertension increased by 26% for each hour of TV watched per day (OR=1.26, 95% CI=1.13–1.40, p<0.001).
      Table 2Logistic regression model for hypertension in obese children
      UnadjustedAdjusted
      Adjusted for race, BMI z-score, and site.
      Variablep valueOR95% CI (%)p valueOR95% CI (%)
      BMI z-score0.0291.621.05–2.49
      TV per day (hours)
       0 to <2
       2 to <4p<0.0012.631.58–4.39p<0.0012.541.51–4.29
       4+p<0.0014.132.50–6.83p<0.0013.291.95–5.56
      BMI, body mass index; CI, confidence interval; OR, odds ratio.
      a Adjusted for race, BMI z-score, and site.

      Discussion

      In a multicenter study of obese children, the relationship between time spent watching TV and the presence of hypertension was examined. TV time was positively correlated with the severity of obesity. After controlling for the severity of obesity, TV time was independently associated with the presence of hypertension.
      This study is the first to demonstrate an association between TV and blood pressure in obese children. Elevated blood pressure in children and adolescents is a growing concern, as it is both increasing in prevalence and often remains undiagnosed, particularly among individuals with a systolic pressure less than 140 mmHg or a diastolic pressure less than 90 mmHg. Blood pressure percentiles, which are necessary to indicate blood pressure status in children, are rarely calculated during routine office visits. Since childhood blood pressure is one of the strongest predictors of adult blood pressure,
      • Lauer R.M.
      • Clarke W.R.
      Childhood risk factors for high adult blood pressure: the Muscatine study.
      hypertension present in childhood is a serious risk factor for future cardiovascular morbidity and mortality
      • Raitakari O.T.
      • Juonala M.
      • Kahonen M.
      • et al.
      Cardiovascular risk factors in childhood and carotid artery intima-media thickness in adulthood: the Cardiovascular Risk in Young Finns study.
      and needs to be addressed.
      Increased micronutrient and energy intake may also play a role in the relationship between TV and hypertension, and between TV and the severity of obesity. Research has shown that up to 35% of childrens’ daily total energy consumption is consumed in front of the TV.
      • Matheson D.M.
      • Wang Y.
      • Klesges L.M.
      • Beech B.M.
      • Kraemer H.C.
      • Robinson T.N.
      African-American girls’ dietary intake while watching television.
      • Matheson D.M.
      • Killen J.D.
      • Wang Y.
      • Varady A.
      • Robinson T.A.
      Children’s food consumption during television viewing.
      Foods commonly advertised on television are more frequently consumed than their unadvertised counterparts, and these advertised foods tend to be high in refined sugars (baked sweets, soft drinks) and/or high in fat (fast food, fried foods), giving them a high energy content.
      • Wiecha J.L.
      • Peterson K.E.
      • Ludwig D.S.
      • Kim J.
      • Gortmaker S.L.
      When children eat what they watch: impact of television viewing on dietary intake in youth.
      TV-influenced intake of such high-fat and high-salt foods may contribute to the association between TV and hypertension. Sodium in particular has been associated with hypertension in adults.
      INTERSALT Cooperative Research Group
      INTERSALT: an international study of electrolyte excretion and blood pressure: results for 24 hour urinary sodium and potassium excretion.
      However, studies have shown conflicting results as to the role of salt in hypertension in children.
      • Simons-Morton D.S.
      • Obarzanek E.
      Diet and blood pressure in children and adolescents.
      Whether TV affects the intake of other micronutrients, such as calcium, potassium, and magnesium is unclear, and research on the association of these nutrients with hypertension in children is incomplete.
      • Couch S.C.
      • Daniels S.R.
      Diet and blood pressure in children.
      The increase in the severity of obesity also may be due to dietary choices secondary to TV viewing. TV time has been shown to increase caloric intake.
      • Wiecha J.L.
      • Peterson K.E.
      • Ludwig D.S.
      • Kim J.
      • Gortmaker S.L.
      When children eat what they watch: impact of television viewing on dietary intake in youth.
      • Blass E.M.
      • Anderson D.R.
      • Kirkorian H.L.
      • Pempek T.A.
      • Price I.
      • Koleini M.F.
      On the road to obesity: television viewing increases intake of high-density foods.
      It has also been shown that TV time increases the serving size of fried foods and baked sweets by as much as 1.4 servings per week.
      • Wiecha J.L.
      • Peterson K.E.
      • Ludwig D.S.
      • Kim J.
      • Gortmaker S.L.
      When children eat what they watch: impact of television viewing on dietary intake in youth.
      Together, these factors may contribute to an increase in energy intake not balanced by an increase in energy expenditure, contributing to the relationship between TV and the severity of obesity in this study.
      Television viewing by children also increases perceived psychological stress,
      • Singer M.I.
      • Slovak K.
      • Frierson T.
      • York P.
      Viewing preferences, symptoms of psychological trauma, and violent behaviors among children who watch television.
      promoting amygdala activation, which alters both sympathetic efferent output and hypothalamic–pituitary–adrenal axis responsiveness.
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      • Braglia F.
      • Costoli T.
      • et al.
      Cardiac autonomic reactivity and salivary cortisol in men and women exposed to social stressors: relationship with individual ethological profile.
      Urinary glucocorticoid excretion is linked to aspects of the metabolic syndrome, including blood pressure.
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      • et al.
      Association of psychosocial risk factors with risk of acute myocardial infarction in 11,119 cases and 13,648 controls from 52 countries (the INTERHEART study): case-control study.
      In addition, there is evidence for the role of stress and glucocorticoids in promoting increased caloric intake of “comfort foods,” adiposity, and the metabolic syndrome.
      • Epel E.S.
      • McEwen B.S.
      • Seeman T.
      • et al.
      Stress and body shape: stress-induced cortisol secretion is consistently greater among women with central fat.
      • Dallman M.F.
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      Several studies have shown relationships between stress and unhealthy dietary practices in adolescents
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      and children.
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      • Wright S.M.
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      Dietary restraint and stress-induced snacking in youth.
      Thus, psychological stress secondary to TV viewing may lead to an increase in visceral adiposity, insulin resistance, and sympathetic nervous system activation, all of which may play a role in the association between TV and hypertension, and TV and the severity of obesity in obese children.
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      Diet, obesity, and hypertension: an hypothesis involving insulin, the sympathetic nervous system, and adaptive thermogenesis.
      The strengths of this study included its large sample size and multicenter design, which allowed for a broad age range and ethnic diversity. Many previous studies have focused only on a narrow age range
      • Eisenmann J.C.
      • Bartee R.T.
      • Wang M.Q.
      Physical activity, TV viewing, and weight in U.S. youth: 1999 Youth Risk Behavior survey.
      or ethnic population.
      • Angelopoulos P.D.
      • Milionis H.J.
      • Moschonis G.
      • Manios Y.
      Relations between obesity and hypertension: preliminary data from a cross-sectional study in primary schoolchildren: the children study.
      • Hernandez B.
      • Gortmaker S.L.
      • Colditz G.A.
      • Peterson K.E.
      • Laird N.M.
      • Parra-Cabrera S.
      Association of obesity with physical activity, television programs and other forms of video viewing among children in Mexico City.
      The limitations of this study involved the cross-sectional nature of the analysis, which prevented determination of causation of the associations found. In addition, unmeasured familial factors such as socioeconomic status might play a role in the association between TV viewing and hypertension, and thus should be taken into account in future studies. Furthermore, the cross-sectional design allowed for only one sitting for the measurement of blood pressure. Prior to ethe stablishment of a medical diagnosis of hypertension, three measurements on separate office visits are needed. Finally, the measure of television time relied on individual recall. However, self-reported questionnaires have been used in most studies to date on this topic,
      • Anderson R.E.
      • Crespo C.J.
      • Bartlett S.J.
      • Cheskin L.J.
      • Pratt M.
      Relationship of physical activity and television watching with body weight and level of fatness among children: Results from the third national Health and Nutrition Examination survey.
      • Eisenmann J.C.
      • Bartee R.T.
      • Wang M.Q.
      Physical activity, TV viewing, and weight in U.S. youth: 1999 Youth Risk Behavior survey.
      • Dietz W.H.
      • Gortmaker S.L.
      Do we fatten our children at the TV set? Obesity and television in children and adolescents.
      • Gortmaker S.L.
      • Must A.
      • Sobol A.M.
      • Peterson K.
      • Colditz G.A.
      • Dietz W.H.
      Television viewing as a cause of increasing obesity among children in the United States, 1986–1990.
      • Angelopoulos P.D.
      • Milionis H.J.
      • Moschonis G.
      • Manios Y.
      Relations between obesity and hypertension: preliminary data from a cross-sectional study in primary schoolchildren: the children study.
      • Marshall S.J.
      • Biddle S.J.H.
      • Gorely T.
      • Cameron N.
      • Murdey I.
      Relationships between media use, body fatness and physical activity in children and youth: a meta analysis.
      • Guillaume M.
      • Lapidus L.
      • Bjorntorp P.
      • Lambert A.
      Physical activity, obesity, and cardiovascular risk factors in children The Belgian Luxembourg Child Study II.
      • Hernandez B.
      • Gortmaker S.L.
      • Colditz G.A.
      • Peterson K.E.
      • Laird N.M.
      • Parra-Cabrera S.
      Association of obesity with physical activity, television programs and other forms of video viewing among children in Mexico City.
      and parent reports have been shown to be reasonably accurate estimates of child TV time.
      • Anderson D.R.
      • Field D.E.
      • Collins P.A.
      • Lorch E.P.
      • Nathan J.G.
      Estimates of young children’s time with television: a methodological comparison of parent reports with time-lapse video home observation.
      Furthermore, TV-time estimates were reviewed and confirmed with the parent and child in addition to the initial questionnaire.
      The current study illustrates the need for considerable physician and family involvement to decrease TV time among obese children. The American Academy of Pediatrics (AAP) recommends that children watch less than 2 hours of TV per day,
      American Academy of Pediatrics Committee on Public Education
      Children, adolescents, and television.
      but reports that only half (51%) of pediatricians make this recommendation to patients.
      • Douglas G.A.
      • Oberg C.
      • Sherwood N.E.
      • Story M.
      • Walsh D.A.
      • Hogan M.
      Well-child visits in the video age: pediatricians and the American Academy of Pediatrics’ guidelines for children’s media use.
      One recent study has shown that many parents do not consider the risks of television viewing to apply to their child.
      • Jordan A.B.
      • Hersey J.C.
      • McDivitt J.A.
      • Heitzler C.D.
      Reducing children’s television-viewing time: a qualitative study of children and their parents.
      In this study, only 20% of obese children already comply with these guidelines, and nearly 89% of obese children with hypertension watch 2 or more hours of TV per day. Thus, although decreasing TV time may not be a universal strategy, TV viewing is an attractive target for intervention, particularly among obese children with hypertension. Several studies have demonstrated that changing TV time alone can lead to weight loss, without any changes in physical activity.
      • Robinson T.N.
      Reducing children’s television viewing to prevent obesity.
      • Epstein L.H.
      • Paluch R.A.
      • Gordy C.C.
      • Dorn J.
      Decreasing sedentary behaviors in treating pediatric obesity.
      • Gortmaker S.L.
      • Peterson K.
      • Wiecha J.
      • et al.
      Reducing obesity via a school-based interdisciplinary intervention among youth.
      Further intervention studies are warranted to determine whether similar results could be obtained for reducing blood pressure in obese children.

      Conclusion

      There is a significant association between hours of television watched and both the severity of obesity and the presence of hypertension in obese children. The magnitude of the associations found in this study indicates the need for increased physician and parental compliance to the AAP guidelines for TV viewing. One recent study suggests several strategies to meet these recommendations and to limit negative health outcomes associated with TV viewing; for example, by removing the TV from the child’s bedroom and forbidding TV watching while eating.
      • Jordan A.B.
      • Hersey J.C.
      • McDivitt J.A.
      • Heitzler C.D.
      Reducing children’s television-viewing time: a qualitative study of children and their parents.
      Mechanistic and interventional studies are warranted to determine the causes underlying the association between TV time and hypertension, and whether decreasing TV time can improve blood pressure status in obese children.
      Supported in part by a grant from the Rest Haven Foundation.
      No financial disclosures were reported by the authors of this paper.

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      Linked Article

      • Sedentary Behavior
        American Journal of Preventive MedicineVol. 33Issue 6
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          Elite athletes prefer to sit down as often as possible to aid recovery and prevent fatigue in the legs. This suggests that some (highly) active people choose to spend considerable time being sedentary. There may be some truth to the often-stated view that “when I get the urge to exercise I lie down until the feeling passes.” This suggests that some may find exercise or physical activity aversive and choose sedentary pastimes instead. In short, “sedentary behavior” is a complex topic.
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