Paul J. Veugelers

Effectiveness of School Programs in Preventing Childhood Obesity: A Multilevel Comparison

OBJECTIVES In light of the alarming increase in childhood obesity and lack of evidence for the effectiveness of school programs, we studied the effects of school programs in regard to preventing excess body weight. METHODS In 2003, we surveyed 5200 grade 5 students along with their parents and school principals. We measured height and weight, assessed dietary intake, and collected information on physical and sedentary activities. We compared excess body weight, diet, and physical activity across schools with and without nutrition programs using multilevel regression methods while adjusting for gender and socioeconomic characteristics of parents and residential neighborhoods. RESULTS Students from schools participating in a coordinated program that incorporated recommendations for school-based healthy eating programs exhibited significantly lower rates of overweight and obesity, had healthier diets, and reported more physical activities than students from schools without nutrition programs. CONCLUSIONS Our finding that school programs are effective in preventing childhood obesity supports the need for broader implementation of successful programs, which will reduce childhood obesity and, in the longer term, comorbid conditions and health care spending.

Prevalence of and risk factors for childhood overweight and obesity

Background: Increases in childhood overweight and obesity have become an important public health problem in industrialized nations. Preventive public health action is required, but more research of risk factors is required before evidence-based initiatives can be developed and targeted effectively. We investigated the association between childhood overweight and obesity and risk factors relating to dietary habits, actitivities, parents and schools. Methods: In 2003 we surveyed grade 5 students and their parents and school principals in Nova Scotia. We measured height and weight and assessed dietary habits (using Harvards Youth/Adolescent Food Frequency Questionnaire), physical and sedentary activities, and parental and school-based risk factors. We estimated neighbourhood income by averaging, per school, the postal-code level means of household income of residential addresses of children attending that school. We used multilevel logistic regression to evaluate the significance of these risk factors for overweight and obesity. Results: On the basis of measurements taken of 4298 grade 5 students, we estimated the provincial prevalence of overweight to be 32.9% and of obesity to be 9.9%. Children who bought lunch at school were at increased risk of overweight (fully adjusted odds ratio [OR] 1.39, 95% confidence interval [CI] 1.16–1.67), whereas those who ate supper together with their family 3 or more times a week were at decreased risk (OR 0.68, 95% CI 0.52–0.88). Physical education classes 2 or more times a week at school were associated with a decreased risk of overweight (OR 0.61, 95% CI 0.43–0.87) and obesity (OR 0.54, 95% CI 0.33–0.88). Children in high-income neighbourhoods were half as likely to be obese as their peers living in low-income neighbourhoods (OR 0.50, 95% CI 0.36–0.70). Interpretation: Parents and schools provide important opportunities for public health initiatives for reducing childhood overweight and obesity. Children and schools in low-income neighbourhoods should receive priority in public health initiatives to reduce future socioeconomic inequalities in health.

Diet Quality and Academic Performance

BACKGROUND Although the effects of nutrition on health and school performance are often cited, few research studies have examined the effect of diet quality on the academic performance of children. This study examines the association between overall diet quality and academic performance. METHODS In 2003, 5200 grade 5 students in Nova Scotia, Canada, and their parents were surveyed as part of the Childrens Lifestyle and School-performance Study. Information on dietary intake, height, and weight and sociodemographic variables were linked to results of a provincial standardized literacy assessment. Diet Quality Index-International was used to summarize overall diet quality. Multilevel regression methods were used to examine the association between indicators of diet quality and academic performance while adjusting for gender and socioeconomic characteristics of parents and residential neighborhoods. RESULTS Across various indicators of diet quality, an association with academic performance was observed. Students with decreased overall diet quality were significantly more likely to perform poorly on the assessment. Girls performed better than boys as did children from socioeconomically advantaged families. Children attending better schools and living in wealthy neighborhoods also performed better. CONCLUSIONS These findings demonstrate an association between diet quality and academic performance and identify specific dietary factors that contribute to this association. Additionally, this research supports the broader implementation and investment in effective school nutrition programs that have the potential to improve student access to healthy food choices, diet quality, academic performance, and, over the long term, health.

Death in children with epilepsy: a population-based study

BACKGROUND Families of children with newly diagnosed epilepsy worry about death during a seizure. We aimed to assess the frequency and causes of death of children with epilepsy. METHOD We did a population-based cohort study. The Nova Scotia epilepsy cohort includes all children who developed epilepsy during 1977-85. In 1999, we matched names and birth dates with provincial health-care, death, and marriage registries. We examined death certificates, necropsy reports, and physician records of children who had died and contacted families if sudden unexpected death in epilepsy could have occurred. We measured the effect of sex, age, epilepsy type, and disorder sufficient to cause functional neurological deficit on death rate. We compared cohort mortality with rates in a reference population matched for age and sex. FINDINGS 26 (3.8%) of 692 children with epilepsy died. Frequency of death was 5.3 times higher (95% CI 2.29-8.32) than in the reference population in the 1980s and 8.8 times higher (4.16-13.43) in the 1990s. Kaplan-Meier curves showed 6.1% mortality 20 years after onset compared with 0.88% in the reference population. Deaths occurred in one (1%) of 97 children with absence epilepsy, 12 (2%) of 510 with partial and primary generalised epilepsy, and 13 (15%) of 85 with secondary generalised epilepsy. 22 deaths were caused by disorders sufficient to cause functional neurological deficit, one by probable sudden unexpected death in epilepsy, two by suicide, and one by homicide. Functional neurological deficit was the only independent determinant of mortality. INTERPRETATION Death from epilepsy is uncommon in children without a severe neurological disorder sufficient to cause functional neurological deficit and sudden unexpected death in epilepsy is rare.

Outcome and Prognostic Factors of Restenosis after Percutaneous Treatment of Native Hemodialysis Fistulas

PURPOSE To assess patency after percutaneous treatment of dysfunctional and thrombosed native arteriovenous fistulas and to examine predictors of patency after intervention. MATERIALS AND METHODS A cohort of 65 consecutive patients with dysfunctional (n = 53) or occluded (n = 12) native fistulas who underwent 96 percutaneous interventions over an 18-month period was retrospectively analyzed. Fistula locations were radiocephalic (n = 37), brachiocephalic (n = 10), or brachiobasilic (n = 18). Primary interventions consisted of angioplasty (n = 50), stent placement (n = 3), or percutaneous thrombolysis/thrombectomy (n = 12). Additional interventions during follow-up consisted of angioplasty (n = 22), stent placement (n = 6), or percutaneous thrombolysis/thrombectomy (n = 3). Duration of fistula function was assessed clinically and examined as a function of anatomic and clinical variables with use of Cox hazards models and the Kaplan-Meier method. RESULTS Clinical success with resumption of at least one session of normal dialysis occurred in 94% (90 of 96) of interventions. The 30-day morbidity rate was 2.1%; no procedure-related deaths occurred. Primary, assisted primary, and secondary patency rates (+/- SE) of dysfunctional fistulas after intervention at 12 months were 26% +/- 11%, 80% +/- 6%, and 82% +/- 6%. Occluded fistulas after intervention had 3-month primary, assisted primary, and secondary patency rates of 60% +/- 15%, 60% +/- 15%, and 80% +/- 13%. Lesions 2.0 cm or more in length were five times more likely to have loss of patency than lesions smaller than 2.0 cm. The presence of at least one comorbid factor--diabetes, coronary artery disease, or peripheral vascular disease--was associated with nearly twice the risk of patency loss after any intervention. CONCLUSION Despite modest primary patency rates in our experience, high assisted and secondary patency rates can be achieved with percutaneous intervention in native arteriovenous fistulas. These findings emphasize the need for close surveillance of native fistulas and a low threshold for diagnostic fistulography after initial intervention. The most detrimental determinant of outcome was lesion length > or =2 cm.

Socioeconomic disparities in health care use: Does universal coverage reduce inequalities in health?

Background: Despite enormous public sector expenditures, the effectiveness of universal coverage for health care in reducing socioeconomic disparities in health has received little attention. Study objectives: To evaluate whether universal coverage for health care reduces socioeconomic disparities in health. Design: Information on participants of the 1990 Nova Scotia Nutrition Survey was linked with eight years of administrative health services data and mortality. The authors first examined whether lower socioeconomic groups use more health services, as would be expected given their poorer health status. They then investigated to what extent differential use of health services modifies socioeconomic disparities in mortality. Finally, the authors evaluated health services use in the last years of life when health is poor regardless of a person’s socioeconomic background. Setting: The Canadian province of Nova Scotia, which provides universal health care coverage to all residents. Participants: 1816 non-institutionalised adults, aged 18–75 years, from a two stage cluster sample stratified by age, gender, and region. Main results: People with lower socioeconomic background used comparatively more family physician and hospital services, in such a way as to ameliorate the socioeconomic differences in mortality. In contrast, specialist services were comparatively underused by people in lower socioeconomic groups. In the last three years of life, use of specialist services was significantly higher in the highest income group. Conclusions: Universal coverage of family physician and hospital services ameliorate the socioeconomic differences in mortality. However, specialist services are underused in lower socioeconomic groups, bearing the potential to widen the socioeconomic gap in health.

Glucose-lowering agents and cancer mortality rates in type 2 diabetes: assessing effects of time-varying exposure

Aims/hypothesisWe explored the relationship between glucose-lowering agents and cancer mortality rates in type 2 diabetes patients, hypothesising a decreased risk of cancer mortality with metformin use and a dose–risk gradient for insulin therapy.MethodsThis was a population-based cohort study using administrative data from Saskatchewan Health, Canada. We identified new users of metformin or sulfonylureas from 1 January 1991 to 31 December 1996, with follow-up until death, departure from the province or 31 December 1999. Cox regression analyses were used to estimate the HR of death from cancer, accounting for time-varying exposure to metformin, sulfonylurea, and exogenous insulin therapy.ResultsWe identified 10,309 new users of metformin or sulfonylurea. The average follow-up was 5.4 (1.9) years, during which 407 (4.0%) cancer deaths occurred. Adjusting for age, sex and chronic disease score, the adjusted HR for metformin use was 0.80 (95% CI 0.65–0.98) compared with sulfonylurea monotherapy users. Adjusted HRs for subsequent insulin use were 2.22 (0.99–5.00), 3.33 (2.26–4.89) and 6.40 (4.69–8.73) for <3, 3 to 11 and ≥12 insulin dispensations/year, respectively, compared with patients not on insulin. We observed a similar risk gradient among the sub-cohort of new insulin users.Conclusions/interpretationOur results support previous reports of a decreased risk of cancer outcomes associated with metformin use relative to sulfonylurea monotherapy. We also provide new evidence of a gradient of cumulative insulin dispensations and cancer mortality rates.

Neighborhood characteristics in relation to diet, physical activity and overweight of Canadian children

BACKGROUND Neighborhood infrastructure may provide an important opportunity to prevent overweight among children. In the present study we investigated whether access to shops for modestly priced fresh produce, access to parks and playgrounds, access to recreational facilities and neighborhood safety are related to childrens diet, physical and sedentary activities, and body weights. METHODS Data were obtained from the Childrens Lifestyle and School-performance Study, a survey including 5,471 grade five students and their parents in the province of Nova Scotia, Canada. Students completed the Harvard Food Frequency Questionnaire and had their height and weight measured. Parents completed questions on socio-economic background and how they perceived their neighborhood. We applied multilevel regression methods to relate these neighborhood characteristics with childrens fruit and vegetable consumption, dietary fat intake, diet quality, frequency of engaging in sports with and without a coach, screen time, overweight and obesity. RESULTS Children in neighborhoods with greater perceived access to shops had healthier diets and were less likely to be overweight or obese. Children in neighborhoods with good access to playgrounds, parks and recreational facilities were reportedly more active and were less likely to be overweight or obese, whereas children in safe neighborhoods engaged more in unsupervised sports. CONCLUSIONS The study demonstrated associations between neighborhood characteristics, health behaviors and childhood overweight. This contributes to the knowledge base that is still too narrow to justify informed preventative public health policy. We advocate the evaluation of natural experiments created by new policy that affect neighborhood infrastructures as the optimal opportunity to enlarge this knowledge base.

Prevalence and sociodemographic risk factors related to household food security in Aboriginal peoples in Canada.

OBJECTIVE Canadas Aboriginal population is vulnerable to food insecurity and increasingly lives off-reserve. The Canadian Community Health Survey, Cycle 2.2 Nutrition, was used to compare the prevalence and sociodemographic correlates of food insecurity between non-Aboriginal and off-reserve Aboriginal households. DESIGN Food insecurity status was based on Health Canadas revised interpretation of responses to the US Household Food Security Survey Module. Logistic regression was used to assess if Aboriginal households were at higher risk for food insecurity than non-Aboriginal households, adjusting for household sociodemographic factors. SETTING Canada. SUBJECTS Households (n 35,107), 1528 Aboriginal and 33 579 non-Aboriginal. RESULTS Thirty-three per cent of Aboriginal households were food insecure as compared with 9 % of non-Aboriginal households (univariate OR 5.2, 95 % CI 4.2, 6.3). Whereas 14 % of Aboriginal households had severe food insecurity, 3 % of non-Aboriginal households did. The prevalence of sociodemographic risk factors for household food insecurity was higher for Aboriginal households. Aboriginal households were more likely to have three or more children (14 % v. 5 %), be lone-parent households (2 1 % v. 5 %), not have home ownership (52 % v. 31 %), have educational attainment of secondary school or less (43 % v. 26 %), have income from sources other than wages or salaries (38 % v. 29 %), and be in the lowest income adequacy category (33 % v. 12 %). Adjusted for these sociodemographic factors, Aboriginal households retained a higher risk for food insecurity than non-Aboriginal households (OR 2.6, 95 % CI 2.1, 3.2). CONCLUSIONS Off-reserve Aboriginal households in Canada merit special attention for income security and poverty alleviation initiatives.

Increased Cancer-Related Mortality for Patients With Type 2 Diabetes Who Use Sulfonylureas or Insulin Response to Farooki and Schneider

We thank Farooki and Schneider (1) for their comments on our recently published article (2) on diabetes treatments and cancer-related mortality. As we had indicated (2), we agree with Drs. Farooki and Schneider that additional clinical data would aid our understanding of pathophysiologic mechanisms. Clinical intervention studies may be optimal in obtaining such pathophysiologic data. However, such studies may be impractical given the large numbers of patients required …