Volume, patterns, and types of sedentary behavior and cardio-metabolic health in children and adolescents: a cross-sectional study

BMC Public Health, May 2011

Background Cardio-metabolic risk factors are becoming more prevalent in children and adolescents. A lack of moderate-to-vigorous intensity physical activity (MVPA) is an established determinant of cardio-metabolic risk factors in children and adolescents. Less is known about the relationship between sedentary behavior and cardio-metabolic health. Therefore, the objective was to examine the independent associations between volume, patterns, and types of sedentary behavior with cardio-metabolic risk factors among children and adolescents. Methods The results are based on 2527 children and adolescents (6-19 years old) from the 2003/04 and 2005/06 National Health and Nutrition Examination Surveys (NHANES). A cardio-metabolic risk score (CRS) was calculated based on age- and sex-adjusted waist circumference, systolic blood pressure, non-high-density lipoprotein cholesterol, and C-reactive protein values. Volume and patterns of sedentary behavior and moderate-to-vigorous physical activity (MVPA) were measured objectively using accelerometers. Types of sedentary behavior were measured by questionnaire. A series of logistic regression models were used to examine associations. Results Volume and patterns of sedentary behavior were not predictors of high CRS after adjusting for MVPA and other confounders (P > 0.1). For types of sedentary behavior, high TV use, but not high computer use, was a predictor of high CRS after adjustment for MVPA and other confounders. Children and adolescents who watched ≥4 hours per day of TV were 2.53 (95% confidence interval: 1.45-4.42) times more likely to have high CRS than those who watched <1 hour per day. MVPA predicted high CRS after adjusting for all sedentary behavior measures and other confounders. After adjustment for waist circumference, MVPA also predicted high non-obesity CRS; however, the same relationship was not seen with TV use. Conclusion No association was observed between overall volume and patterns of sedentary behavior with cardio-metabolic risk factors in this large sample of children and adolescents. Conversely, high TV use and low MVPA were independently associated with cardio-metabolic risk factors. However, the association between high TV use and clustered cardio-metabolic risk factors appears to be mediated or confounded by obesity. Thus, TV and MVPA appear to be two separate behaviors that need to be targeted with different interventions and policies.

A PDF file should load here. If you do not see its contents the file may be temporarily unavailable at the journal website or you do not have a PDF plug-in installed and enabled in your browser.

Alternatively, you can download the file locally and open with any standalone PDF reader:

http://www.biomedcentral.com/content/pdf/1471-2458-11-274.pdf

Volume, patterns, and types of sedentary behavior and cardio-metabolic health in children and adolescents: a cross-sectional study

BMC Public Health Volume, patterns, and types of sedentary behavior and cardio-metabolic health in children and adolescents: a cross-sectional study Valerie Carson 0 2 Ian Janssen 0 1 2 0 School of Kinesiology and Health Studies, Queen's University , Kingston, ON , Canada 1 Department of Community Health and Epidemiology, Queen's University , Kingston, ON , Canada 2 School of Kinesiology and Health Studies, Queen's University , Kingston, ON , Canada Background: Cardio-metabolic risk factors are becoming more prevalent in children and adolescents. A lack of moderate-to-vigorous intensity physical activity (MVPA) is an established determinant of cardio-metabolic risk factors in children and adolescents. Less is known about the relationship between sedentary behavior and cardiometabolic health. Therefore, the objective was to examine the independent associations between volume, patterns, and types of sedentary behavior with cardio-metabolic risk factors among children and adolescents. Methods: The results are based on 2527 children and adolescents (6-19 years old) from the 2003/04 and 2005/06 National Health and Nutrition Examination Surveys (NHANES). A cardio-metabolic risk score (CRS) was calculated based on age- and sex-adjusted waist circumference, systolic blood pressure, non-high-density lipoprotein cholesterol, and C-reactive protein values. Volume and patterns of sedentary behavior and moderate-to-vigorous physical activity (MVPA) were measured objectively using accelerometers. Types of sedentary behavior were measured by questionnaire. A series of logistic regression models were used to examine associations. Results: Volume and patterns of sedentary behavior were not predictors of high CRS after adjusting for MVPA and other confounders (P > 0.1). For types of sedentary behavior, high TV use, but not high computer use, was a predictor of high CRS after adjustment for MVPA and other confounders. Children and adolescents who watched ≥4 hours per day of TV were 2.53 (95% confidence interval: 1.45-4.42) times more likely to have high CRS than those who watched <1 hour per day. MVPA predicted high CRS after adjusting for all sedentary behavior measures and other confounders. After adjustment for waist circumference, MVPA also predicted high non-obesity CRS; however, the same relationship was not seen with TV use. Conclusion: No association was observed between overall volume and patterns of sedentary behavior with cardiometabolic risk factors in this large sample of children and adolescents. Conversely, high TV use and low MVPA were independently associated with cardio-metabolic risk factors. However, the association between high TV use and clustered cardio-metabolic risk factors appears to be mediated or confounded by obesity. Thus, TV and MVPA appear to be two separate behaviors that need to be targeted with different interventions and policies. Background Cardio-metabolic risk factors, such as obesity, hypertension, dyslipidemia, and glucose intolerance, are known predictors of coronary heart disease and type 2 diabetes among adults [ 1 ]. These risk factors are becoming more prevalent in children and adolescents, and approximately 50% of American youth have at least one cardiometabolic risk factor [ 2 ]. This is concerning as cardiometabolic risk factors track from childhood to adulthood [ 1 ]. In addition, cardio-metabolic risk factors during adolescence predict the development of sub-clinical cardiovascular disease [ 3 ], coronary heart disease [ 4 ], and mortality in adulthood [ 5 ]. Therefore, improving the cardio-metabolic risk factor profile of young people has long-term implications on population health. Physical inactivity is an established determinant of cardio-metabolic risk factors in children and adolescents [ 6 ]. The majority of physical inactivity research has focused on how inadequate moderate-to-vigorous intensity physical activity (MVPA) influences health [ 7 ]. However, even within highly active persons, MVPA accounts for only a fraction of total energy expenditure [ 8 ]. An emerging area of study is the relation between sedentary behavior and health [ 7 ]. Sedentary behavior refers to activities that involve minimal body movement and low energy expenditure [ 9 ]. To date, two studies have examined the relationship between the overall volume of sedentary behavior with a summary cardiometabolic risk score among children and adolescents [ 10,11 ]. Although both studies found significant associations, the results need to be interpreted with caution. Specifically, neither study adjusted for MVPA even though MVPA is an independent predictor of cardiometabolic risk factors [12]. In addition to the overall volume, the type of sedentary behavior appears to impact cardio-metabolic health. For example, a recent review reported that TV use is more strongly related to obesity than video game and computer use in young people [ 13 ]. A limitation of the existing scr (...truncated)


This is a preview of a remote PDF: http://www.biomedcentral.com/content/pdf/1471-2458-11-274.pdf

Valerie Carson, Ian Janssen. Volume, patterns, and types of sedentary behavior and cardio-metabolic health in children and adolescents: a cross-sectional study, BMC Public Health, 2011, pp. 274, 11, DOI: 10.1186/1471-2458-11-274