Abstracts Category : Other

Associations Between Cardio-Metabolic Risk Factors and Weight Status Among Canadian Children and Adolescents Using the Canadian Health Measures Survey

by Miranda MacPherson

Objectives: This thesis examines the risks among Canadian children and adolescents for developing cardio-metabolic diseases, extending evidence that is well-established for adults to pediatric populations. As well, novel indicators and cut-offs for the measurements of disease risks are proposed and associations between physical activity, weight status, socio-economic status and cardio-metabolic health are examined.Methodology: Secondary data analysis was conducted using data from three cycles of the Canadian Health Measures Survey (CHMS), a nationally representative data set which includes measured anthropometric characteristics. A population health approach was applied throughout, underpinned by the World Health Organizations Conceptual Framework for Action on the Social Determinants of Health. The thesis was designed such that a series of four manuscripts successively built on the key findings from each previous research paper:1. Establishing the prevalence of Metabolic Syndrome and its risk factors for 10-18 year olds using the International Diabetes Federation child, adolescent and adult definitions. 2. Estimating pre-obesity epidemic waist circumference reference values for Canadian children 6-10 years using reference data from the 1981 Canada Fitness Survey, the Third National Health and Nutrition Examination Survey (1988-1994), and the CHMS through regression of linear, logarithmic and quadratic functions. This work facilitated an expanded age range for the subsequent projects as age- and sex-specific cut-offs based on a Canadian population prior to the obesity epidemic had not been available.3. Cardio-metabolic risk by body mass index (BMI), waist circumference (WC), and a combined BMI-WC indicator quantified the associations between a dichotomous cardio-metabolic risk variable, and obesity, using three indicators of obesity including a novel indicator, for ages 6-18 years. 4. Association between cardio-metabolic risk and inflammation quantified the associations between inflammation, using high-sensitivity c-reactive protein (CRP) as a marker, and cardio-metabolic risk to determine if high CRP was a significant predictor of cardiometabolic risk among 6-18 year olds. Results: For Paper 1 (n=1228), only 2.1% were classified as having the Mets though 38% had at least 1 MetS risk factor. For Paper 2, logarithmic regression predicted WC cut-offs with the lowest degree of error. For Paper 3 (n=2678), 35% were classified as having cardio-metabolic risk with significantly higher levels among those classified as obese and/or having a low level of physical activity. All indicators of obesity had significant associations with cardio-metabolic risk. For Paper 4 (n=1831), 43.6% of children and 62.0% of adolescents with high CRP levels were classified as having cardio-metabolic risk, a significant relationship. Participants from households with moderate to high income and/or education had the lowest prevalence of MetS risk factors and abdominal obesity. Conclusions: High CRP is a useful indicator of