A Province-Wide Life-Course Database on Child Development and Health

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1 Patterns of health and disease are largely a consequence of how we learn, live and work A Province-Wide Life-Course Database on Child Development and Health Summary of Results April 2007 Principal Investigator Paul Veugelers, PhD Department of Public Health Sciences University of Alberta Funding provided by: Canadian Population Health Initiative Canadian Population Health Initiative

2 Funded Research Disclaimer The content of this report is provided from a Canadian perspective and for information purposes only. The Canadian Institute for Health Information (CIHI) makes no representations or warranties concerning the accuracy, completeness, timeliness, reliability or usefulness of the information. You are responsible for independently verifying the truth and accuracy of any information; any reliance on the content found in this report will be at your own risk. The publication of this report funded by the Canadian Population Health Initiative (CPHI) of CIHI is not an endorsement by CPHI of its content and is not indicative of any commitment by CPHI to any particular view, opinion or course of action. The contents of this publication may be reproduced in whole or in part, provided the intended use is for non-commercial purposes and full acknowledgement is given to CIHI. Production of this report is made possible by financial contributions from Health Canada. The views expressed herein do not necessarily represent the views of Health Canada, CPHI or CIHI. Canadian Institute for Health Information 495 Richmond Road, Suite 600 Ottawa, Ontario K2A 4H6 Phone: Fax: ISBN (PDF) 2009 Canadian Institute for Health Information How to cite this document: Canadian Institute for Health Information, A Province-Wide Life-Course Database on Child Development and Health (Ottawa, Ont.: CIHI, 2009). Cette publication est aussi disponible en français sous le titre Une base de données sur le déroulement d une vie dans toute une province concernant le développement et la santé de l enfant. ISBN (PDF)

3 Research Context This research program examined the health, nutrition, obesity, school performance and social environments of Grade 5 students (10 to 11 years of age) in Nova Scotia. Eight separate but related papers provided insights into various determinants of child health and their associations with health and academic outcomes. The 2003 Children s Lifestyle and School-Performance Study (CLASS) served as a principal source of data for the investigation. In Nova Scotia, 282 public schools participated by completing a short survey and distributing a consent form and questionnaire to the parents of all fifth-grade students. Parental consent was received for 5,517 students, resulting in an average response rate of 51.1% per school. CLASS representatives administered a modified version of Harvard s Youth Adolescent Food Frequency Questionnaire (YAQ) that gathered information on both dietary intake and meal-time behaviours. Of the 5,517 children who received parental consent, 5,200 completed the YAQ. Students activities were measured by the frequency of physical activities, the frequency of sedentary activities and the methods of transportation to and from school. Overweight and obesity rates were calculated based on health-related adult definitions of overweight and obesity (25 and 30 kg/m 2, respectively), which were adjusted to specific age and gender categories for children. Participants parents completed a survey, which included the child s gender, place of birth and residency; and parental marital status, income and educational attainment. Neighbourhood wealth was estimated by the average household income at the postal-code level of that neighbourhood. Information on school characteristics was obtained through a short survey completed by school principals. It included the sales of soft drinks, the presence of vending machines, the type of food services, the frequency of physical education and possible financial constraints on recreation and gymnasium equipment. Research Results Prevalence and Risk Factors for Childhood Overweight and Obesity The prevalence of overweight and obesity among Grade 5 students in Nova Scotia was found to be 32.9% and 9.9%, respectively. Students who reported skipping breakfast (3.7% of all students) were 1.5 times more likely to be overweight. Children who reported buying lunch at school were 47% more likely to be overweight than those who brought their lunch from home. The likelihood of being overweight appeared to increase with a decrease in the frequency of physical education classes at school. 1

4 Effectiveness of School Programs in Preventing Childhood Obesity The effectiveness of school programs in preventing childhood obesity was examined through a comparison of three groups of schools: Schools without a nutrition program; Schools with a nutrition program; and Schools that were part of the Annapolis Valley Health Promoting Schools Project (AVHPSP). i The rates of overweight were found to be 32.8%, 34.2% and 17.9%, respectively. Students from AVHPSP schools reported less participation in sedentary activities and more in physical activities. Consumption of fruits and vegetables, as well as overall diet quality scores, ii were also higher for students from AVHPSP schools compared with the other two groups of schools. Dietary Intake and Risk Factors for Poor Diet Quality Among Children in Nova Scotia Many Grade 5 students did not meet the minimum recommendations of Canada s Food Guide: 42.3% of students did not meet the minimum recommendations for milk products; 49.9% for fruits and vegetables; 54.4% for grain products; and 73.7% for meat and alternatives. The overall diet quality appeared to be better among girls; boys had an 11% higher risk of lower diet quality. Eating at a fast food restaurant three or more times per week was associated with a 56% increased risk for lower diet quality. Other risk factors for poorer diet quality included less participation in physical activity, frequent participation in sedentary activities and frequent consumption of meals in front of the television. Children s Preference for Large Portions: Prevalence, Determinants and Consequences The survey demonstrated that many children are likely to choose a larger portion than recommended. iii Sixty-three and a half percent of children chose larger-than-recommended portions of french fries, 77.9% chose larger portions of meat and 78.2% of potato chips. Boys were more likely than girls to choose excessive portions, for example, they were 2.5 times more likely to eat too many french fries and 2.3 times more likely to eat too much meat. Children who preferred excessive portion sizes consumed more calories per day than the average Grade 5 student. Yet, the authors found no association between children s preferences for large portions and the probability of being overweight. i. For the AVHPSP description see < ii. Diet quality scores are measured by the Diet Quality Index International a summary measure that encompasses dietary adequacy, variety, moderation and balance. Each category is assigned a score based on a number of factors. The sum of these scores then provides an overall score from 0 to 100, with a score of 100 signifying the best possible diet quality. iii. Canada s Food Guide to Healthy Eating guidelines define appropriate portion sizes to be 71 g (2.5 oz) for french fries, 85 g (3 oz) for meats, 96 g (1/2 cup) for cooked vegetables and 28 g (1 oz) for potato chips. 2

5 Neighbourhood Characteristics in Relation to Diet, Physical Activity and Overweight Among Canadian Children The authors examined the influence of various neighbourhood characteristics on diet, physical activity and body weight. Neighbourhoods were divided into three categories: good, fair or poor access to selected resources. iv In comparison to children with poor access to shops, children with good access were 23% less likely to be overweight and reported: More consumption of fruit and vegetables; Less consumption of dietary fat; and Higher diet quality. In comparison to children with poor access to parks, playgrounds and recreational facilities, children with good access were 23% to 27% less likely to be overweight and reported: More engagement in sports with coach ; and Less time in front of a computer or TV screen. Body Weight and Childhood Asthma: A Linear Association? Among Grade 5 students, overweight boys and girls were more likely to have asthma and allergies than children who were not overweight. For example, 39.6% of girls who were overweight had allergies and asthma, compared with 30.7% of overweight girls who had neither allergies nor asthma. Similarly, 38.2% of boys who were overweight had allergies and asthma, compared with 31.4% of overweight boys who did not have allergies or asthma. There appeared to be an association between body mass index and the prevalence of asthma. For both boys and girls, the risk of asthma increased by 6% per unit increase in body mass index. Diet Quality and Academic Performance in Nova Scotia Grade 5 Students Grade 5 students were divided into three diet quality groups: lowest, average and highest diet quality. The academic performance was measured by the standardized Elementary Literary Assessment test. Increased diet quality appeared to be associated with increased academic performance. Students with average diet quality were 26% less likely to fail the test compared with students with lowest diet quality; students with highest diet quality were 41% less likely to fail compared with the lowest group. iv. Selected resources included access to shops, playgrounds, parks and recreational facilities; and a safe place for children to play. 3

6 Are Children Reporting Their Physical and Sedentary Activity Accurately? Or Are Their Activities Better Reported by Their Parents? Both Grade 5 students and their parents were asked to report on frequency of the students sedentary and physical activities. Students who reported more physical activity and/or less sedentary activity than their parents were more likely to be overweight or obese than those who agreed with their parents. Overweight or obese children may overestimate their physical activity and underestimate their sedentary activity due to a social desirability bias. The authors concluded that parents reports were more accurate in measuring children s activity levels. Author-Identified Policy Implications The research results presented in this report suggest ways to enhance the health and well-being of adolescents in Canada. School nutrition policies may benefit from placing more emphasis on encouraging healthy eating habits, promoting access to healthy meals and discouraging the consumption of foods high in fat, sugar and salt. Also, more frequent physical education classes could be considered as an option to prevent overweight and to increase physical fitness. The authors recommend comprehensive school health programs as an opportunity to mitigate overweight and obesity in Canadian children. Comprehensive programs could include healthy lunch offerings, no junk food policies, daily physical activities, a comprehensive health and nutrition curriculum and parental and community involvement. The lessons from the Annapolis Valley Health Promoting Schools Project may be valuable for other Canadian jurisdictions. The authors point to the role of parents in encouraging the optimal health of their children. Among other things, parents may consider discouraging children from eating in front of the television. Healthy family meals are seen as an important contribution to developing healthy habits. Favourable neighbourhood and school environments also appear to influence healthy living habits. Easy access to healthy food and recreational facilities as well as physical safety seem to be conducive to advancing the health of Canadian children. 4

7 This publication is part of CPHI s ongoing inquiry into the patterns of health across this country. Consistent with our broader findings, it reflects the extent to which the health of Canadians is socially determined, interconnected, complex and changing. CPHI is committed to deepening our understanding of these patterns. Taking health information further À l avant-garde de l information sur la santé