The longitudinal impact of diet, physical activity, sleep, and screen time on Canadian adolescents' academic achievement: An analysis from the COMPASS study.

Adequate amounts of physical activity, sleep, and screen time along with a healthy diet have been demonstrated to have positive associations with academic achievement. No longitudinal study has investigated the simultaneous relationship between all of these behaviours and academic achievement. Data from 11,016 adolescent participants of the COMPASS study in Alberta and Ontario were analysed. Students self-reported their adherence to Canadian recommendations for health behaviours and academic achievement in Math and English on school-based surveys administered in the 2015/16 and 2016/17 waves of COMPASS. Multinomial generalized estimating equations were used to evaluate the association between longitudinal changes in adherence to recommendations and academic achievement at follow-up. Models were adjusted for self-reported sociodemographic information, body weight status, and baseline academic achievement. Students who adhered to a greater number of recommendations performed better than students who adhered to fewer recommendations. Meeting recommendations for Meat and Alternatives (protein-rich foods) and screen time were consistently associated with higher academic achievement compared to students who did not meet these recommendations. A change from not meeting recommendations for Vegetables and Fruit to meeting the recommendation in the following year was associated with higher achievement in both subjects. There was no association between sleep behaviours or physical activity and academic achievement. Results indicate that adherence to recommendations for protein-rich foods, screen time, and vegetables and fruit show promise as behavioural targets for higher academic achievement among youth. Further study using objectives measurements of behaviours and further consideration of socioeconomic variables is merited.

Vitamin D and health-related quality of life in a community sample of older Canadians.

PURPOSE: To assess how vitamin D status is associated with health-related quality of life (HRQOL) among older residents of Canada. DESIGN: We analysed baseline data of 1,493 Canadians aged 50 years and over in Alberta on HRQOL (EQ-5D-5L) and serum 25-hydroxyvitamin D (25(OH)D) as a measure of vitamin D status. We applied multivariable regression methods to examine the association between vitamin D status and each of the five dimensions and the summary index of the EQ-5D-5L. RESULTS: Participants with higher serum 25(OH)D levels were significantly less likely to report problems with mobility, usual activities, and depression and anxiety. Specifically, age- and gender-adjusted odds ratios for reporting problems with mobility, usual activities, and depression and anxiety were 0.58 (95 % confidence interval 0.44-0.78), 0.67 (0.50-0.89), and 0.67 (0.51-0.88) per 100 nmol/L increase in 25(OH)D, respectively. No significant associations were observed for problems with self-care and with pain and discomfort. HRQOL scores combining the responses of each of the five dimensions increased significantly with increasing serum 25(OH)D levels. CONCLUSIONS: This is the first study to reveal the importance of vitamin D for the five dimensions of HRQOL in a community-based sample. The observed associations of vitamin D and HRQOL call for intervention studies to strengthen the evidence of the potential benefits of vitamin D supplementation for HRQOL among older adults.

Assessment of children's own health status using visual analogue scale and descriptive system of the EQ-5D-Y: linkage between two systems.

OBJECTIVES: The objective of the study is to derive a scoring system for the EQ-5D child-friendly version (EQ-5D-Y) from a population-based sample of children based on their own health state assessments on the descriptive system and the visual analogue scale (VAS). METHODS: We used data from the 2008 and 2010 Raising Healthy Eating and Active Living Kids in Alberta surveys of grade five students aged primarily 10-11 years and their parents in the Canadian province of Alberta. We applied a random split sample approach. Two-thirds of the sample (modeling sample) was used for the estimation of the EQ-5D-Y VAS. The remaining one-third sample (validation sample) was used for the examination of the prediction accuracy of the estimation model. Multilevel linear regression was used to estimate EQ-5D-Y VAS score and produce EQ-5D-Y index values from the children's self-rated states described in the EQ-5D-Y and the accompanying VAS values. RESULTS: The mean EQ-5D-Y VAS-based index value was 0.891 (SD 0.133) in the modeling sample and 0.885 (SD 0.134) in the validation sample. The own VAS-based index generally showed logical consistency, with lower values for health states that were logically worse. There was no statistically significant difference between the observed and the predicted VAS values in this sample. CONCLUSIONS: This study elicited a value set for health states defined by the EQ-5D-Y that is based on respondents' own VAS ratings from a large representative sample of Canadian children. Future study is needed to validate this type of value set among different age groups of children.

Vitamin D status of Canadians employed in northern latitudes.

BACKGROUND: Vitamin D deficiency and insufficiency are prevalent worldwide, but relatively few studies have examined vitamin D status in working populations. AIMS: To assess the prevalence of vitamin D deficiency and insufficiency in Canadian workers and investigate risk factors in this population. METHODS: A cross-sectional study using data from a health programme enrolling workers mostly from Northern Alberta, Canada. As part of the programme, volunteers were invited to complete a lifestyle questionnaire. Blood was taken to determine plasma 25-hydroxyvitamin D (25(OH)D) levels. Logistic and linear regressions were used to investigate the relationships between individual characteristics and vitamin D status. RESULTS: Between October 2007 and December 2012, 6101 eligible workers enrolled in the health programme. The prevalence of vitamin D deficiency (plasma 25(OH)D, levels <27.5 nmol/l) and insufficiency (<37.5 nmol/l) were 3 and 8%, respectively. Male employees were significantly more likely to be vitamin D deficient and insufficient than females. Residing at a more northern latitude increased the likelihood of vitamin D deficiency and insufficiency. Age, assessments made in summer, better general health and physical activity and use of vitamin D supplementation were all related to lower likelihood of deficiency and insufficiency. CONCLUSIONS: Vitamin D deficiency and insufficiency are a concern in this sample of Canadian workers. Vitamin D supplementation is recommended to reduce the prevalence of deficiency and insufficiency in this group.

Availability and night-time use of electronic entertainment and communication devices are associated with short sleep duration and obesity among Canadian children.

UNLABELLED: What is already known about this subject Short sleep duration is a risk factor for obesity. Television (TV) in the bedroom has been shown to be associated with excess body weight in children. Children increasingly use other electronic entertainment and communication devices (EECDs) such as video games, computers, and smart phones. What this study adds Access to and night-time use of EECDs are associated with shortened sleep duration, excess body weight, poorer diet quality, and lower physical activity levels. Our findings reinforce existing recommendations pertaining to TV and Internet access by the American Academy of Pediatrics and suggest to have these expanded to restricted availability of video games and smart phones in children's bedrooms. BACKGROUND: While the prevalence of childhood obesity and access to and use of electronic entertainment and communication devices (EECDs) have increased in the past decades, no earlier study has examined their interrelationship. OBJECTIVE: To examine whether night-time access to and use of EECDs are associated with sleep duration, body weights, diet quality, and physical activity of Canadian children. METHODS: A representative sample of 3398 grade 5 children in Alberta, Canada, was surveyed. The survey included questions on children's lifestyles and health behaviours, the Harvard Youth/Adolescent Food Frequency questionnaire, a validated questionnaire on physical activity, and measurements of heights and weights. Random effect models were used to assess the associations of night-time access to and use of EECDs with sleep, diet quality, physical activity, and body weights. RESULTS: Sixty-four percent of parents reported that their child had access to one or more EECDs in their bedroom. Access to and night-time use of EECDs were associated with shortened sleep duration, excess body weight, poorer diet quality, and lower physical activity levels in a statistically significant manner. CONCLUSIONS: Limiting the availability of EECDs in children's bedrooms and discouraging their night-time use may be considered as a strategy to promote sleep and reduce childhood obesity.

The association between childhood overweight and obesity and otitis media.

OBJECTIVE: The objective of this study was to examine the association between otitis media and childhood obesity in a population-based sample of elementary school children in the Canadian province of Nova Scotia. METHODS: The study design is a prospective cohort study, linking data from a population-based survey of Grade 5 students (aged 10-11 years) in the Canadian province of Nova Scotia in 2003 with Nova Scotia administrative health data. Measured body mass index was used to define weight status based on the age- and gender-specific cut-off points of the International Obesity Task Force. Health administration data for each child was linked via Health Card numbers. The primary outcome was healthcare utilization (physician visits and costs) for suppurative otitis media (International Classification of Diseases [ICD]9: 382; ICD10: H65-66) with no previous diagnosis of otitis in the last 30 days. RESULTS: Relative to normal weight children, obese children had more healthcare provider contacts for otitis media (adjusted incidence rate ratio 2.03, 95% confidence interval [CI] 1.66-2.49), incurred more costs per otitis media-related visit ($47 vs. $24, P = 0.0001) and had higher odds to have repeated otitis media (adjusted odds ratio 2.27, 95% CI 1.54-3.35). Socioeconomic factors, a history of breastfeeding, presence of an allergic disorder or chronic adenoid/tonsil disorder did not change the association between obesity and otitis media. CONCLUSION: There is a clear association between childhood obesity and otitis media that cannot be explained by confounding by socioeconomic factors or clinically associated disorders.

Sociodemographic and neighbourhood determinants of health-related quality of life among grade-five students in Canada.

OBJECTIVES: To describe the health-related quality of life (HRQOL) of grade-five students in Alberta, Canada, and to assess how this correlates with sociodemographic and neighbourhood characteristics. METHODS: In 2008, we conducted a comprehensive population-based survey among 3,421 grade-five students aged primarily 10-11 years from 148 schools and their parents that included questions on sociodemographic and neighbourhood factors. The HRQOL of the students was assessed using the EQ-5D Canadian English child version (EQ-5D-Y). We applied multilevel multivariable linear regression to examine the independent importance of sociodemographic and neighbourhood factors for the EQ-5D-Y index and EQ-5D-Y Visual Analogue Scale (VAS) score. RESULTS: In five EQ-5D-Y dimensions, problems with 'walking', 'looking after myself', 'usual activities', 'pain or discomfort' and 'worried, sad or unhappy' were reported by 8.1% (n = 288), 6.5% (n = 215), 11.8% (n = 431), 46.0% (n = 1600), and 37.7% (n = 1292) of students, respectively. Their mean EQ-5D-Y index was 0.86 and mean EQ-5D-Y VAS was 80.4. Children from families reporting higher educational attainment reported higher HRQOL both in terms of a higher EQ-5D-Y index and in terms of a higher EQ-5D-Y VAS. Also, children residing in neighbourhood characterized as providing good satisfaction and facilities reported higher HRQOL. CONCLUSIONS: Public health initiatives to improve HRQOL among children are suggested to take into account the influence of different sociodemographic and neighbourhood characteristics such that priority is given to those residing in towns, rural areas and dissatisfying neighbourhoods with poor access to recreational facilities and stores for fresh products.

Neighborhood determinants of self-efficacy, physical activity, and body weights among Canadian children.

OBJECTIVE: To examine the presence and pathways of the influence of neighborhood characteristics on self-efficacy, physical activity (PA) and body weight among pre-adolescent children. DESIGN: In 2008, we surveyed grade 5 students on self-efficacy, physical activity, neighborhood perception and measures of height and weight. We applied multilevel logistic regression methods and structural equation modeling to assess the presence and pathways of the influence of neighborhood characteristics on self-efficacy, PA and body weight. PARTICIPANTS: Of about 3421 grade 5 students from 148 randomly selected schools from across Alberta, Canada. RESULTS: We identified neighborhood satisfaction and services as well as neighborhood sidewalks and parks as determinants of self-efficacy. Over and above various independent associations of neighborhood characteristics with self-efficacy, PA and body weight, self-efficacy exhibited a positive effect on PA and a negative effect on body weight. CONCLUSION: Both infrastructural investments such as in recreational facilities, sidewalks and parks, as well as health education to promote self-efficacy may increase PA and prevent overweight among children.

Disease progression among multiple sclerosis patients before and during a disease-modifying drug program: a longitudinal population-based evaluation.

Randomized controlled trials have demonstrated the efficacy of disease-modifying drugs (DMDs) in persons with relapsing-remitting multiple sclerosis (MS) and secondary progressive MS with superimposed relapses. However, these brief studies of selected patients have focused mainly on reducing attacks and must be complemented by evaluations in 'realworld' clinical settings to establish the effectiveness of DMD programs in slowing disease progression and to inform health policy and program decision-making. We assessed the effectiveness of DMDs as administered in a comprehensive publicly funded drug insurance program that provides DMDs to a geographically defined population of MS patients who meet specific eligibility criteria. Data from 1752 MS patients (10,312 assessments) seen between 1980 and 2004 at a regional MS Clinic serving the entire population of Nova Scotia, Canada were analysed. Using survival methods we observed a statistically significant reduction in disease progression to specific Expanded Disability Status Scale endpoints following the introduction of this program. Subgroup analyses of patients eligible for treatment using hierarchical linear regression methods also suggested that disease progression was slowed in patients treated with the first DMD prescribed. These findings provide evidence supporting DMD program effectiveness that can be used to inform the broader implementation of such programs.

The influence of childhood obesity on the development of self-esteem.

BACKGROUND: The consequences of overweight in childhood for physical health have received considerable attention, but relatively little research has examined the mental health consequences. This article examines longitudinal relationships between body weight and self-esteem in a nationally representative probability sample of Canadian children. DATA AND METHODS: The data are from cycles 1, 2 and 3 of the Canadian National Longitudinal Survey of Children and Youth. Logistic regression analysis using weighted data examined whether body weight at baseline predicted self-esteem two and four years later. RESULTS: When baseline self-esteem and other potential confounders were taken into account, children who were obese at baseline had almost twice the odds of reporting low self-esteem four years later, compared with children of normal body weight. Ancillary analyses indicated that baseline self-esteem was not associated with body weight status two or four years later. INTERPRETATION: The current childhood obesity epidemic may trigger an increase in the population prevalence of low self-esteem in the future. According to other research, low self-esteem predicts poor mental health. The curent childhood obesity epidemic may increase the prevalence of not only chronic diseases, but also poor mental health.

Self-esteem and cognitive development in the era of the childhood obesity epidemic.

Consequences of obesity for mental health and cognitive development are not established to the same degree as those for chronic diseases. This study aims to document the interrelationships between body weight, self-esteem and school performance in childhood. Height and weight measurements and self-report of self-esteem, diet quality and physical activity of 4945 grade 5 students were linked with standardized literacy test results. Structural equation models were applied to confirm hypothesized relationships between body weight, self-esteem and school performance, and revealed that body weight affected self-esteem negatively and that school performance affected self-esteem positively. Body weight did not affect school performance, and self-esteem did affect neither body weight nor school performance. Subsequent multi-level logistic regression showed that obese students, relative to normal weight students, were more likely (1.44; 95% CI: 1.12-1.84), and students with good school performance, relative to those performing poor, were less likely (0.39; 95% CI: 0.26-0.58), to have low self-esteem. Diet quality and active living had positive effects on both school performance and self-esteem. The study findings further establish obesity as a risk factor for low self-esteem and add to the rationale to promote healthy eating and active living among children and youth as this will prevent chronic diseases and improve mental health and cognitive development.

Obesity and lifestyle risk factors for gastroesophageal reflux disease, Barrett esophagus and esophageal adenocarcinoma.

The aim of this study was to examine the association of obesity with esophageal adenocarcinoma, and with the precursor lesions Barrett esophagus and gastroesophageal reflux disease (GERD). This case-control study included cases with GERD (n = 142), Barrett esophagus (n = 130), and esophageal adenocarcinoma (n = 57). Controls comprised 102 asymptomatic individuals. Using logistic regression methods, we compared obesity rates between cases and controls adjusting for differences in age, gender, and lifestyle risk factors. Relative to normal weight, obese individuals were at increased risk for esophageal adenocarcinoma (Odds Ratio [OR] 4.67, 95% Confidence Interval [CI] 1.27-17.9). Diets high in vitamin C were associated with a lower risk for GERD (OR 0.40, 95% CI 0.19-0.87), Barrett esophagus (OR 0.44, 95% CI 0.20-0.98), and esophageal adenocarcinoma (OR 0.21, 95% CI 0.06-0.77). For the more established risk factors, we confirmed that smoking was a significant risk factor for esophageal adenocarcinoma, and that increased liquor consumption was associated with GERD and Barrett esophagus. In light of the current obesity epidemic, esophageal adenocarcinoma incidence rates are expected to continue to increase. Successful promotion of healthy body weight and diets high in vitamin C may substantially reduce the incidence of this disease.

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 OBJECTIVE: s: 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.

Evolution and critical appraisal of anastomotic technique following resection of esophageal adenocarcinoma.

The aim of this study was to critically evaluate acute and long-term complications of hand-sewn and semimechanical cervical esophagogastric anastomosis following resection of primary esophageal adenocarcinoma. Between February 1991 and 2001, 91 consecutive patients underwent subtotal esophagectomy (transthoracic, n=49; transhiatal, n=42), transposing a gastric tube based on the right gastroepiploic artery. All esophagogastric anastomoses were performed in the left neck using a hand-sewn technique (n=53) and, from September 1997, a side-to-side semimechanical technique (n=38). Outcomes evaluated were anastomotic leak rates, length of stay, and development of strictures. Postoperative mortality was 4.4% (all cardiopulmonary causes). Fifty-eight patients (63.7%) had an uncomplicated postoperative course, with a median postoperative length of stay of 10 days (vs. 20 days with associated morbidity; P

Proximate and contextual socioeconomic determinants of mortality: multilevel approaches in a setting with universal health care coverage.

Investigations of contextual factors (income inequality, cultural disruption, access to health and social services, safety and crime rate, and others) have received little emphasis by epidemiologists, although a few have demonstrated the importance of such factors for mortality, particularly in the United States. To expand current understanding of the importance of contextual factors, the authors evaluated mortality in a longitudinal study in Nova Scotia, Canada, where all residents have greater access to health and social services and where income inequalities are smaller than in the United States. A total of 2,116 participants were followed from 1990 through December 1999, linked to the 1991 Canada Census as a source of neighborhood characteristics, and analyzed using individual-level and multilevel logistic regression. Well-educated and high-earning persons fared better. Neighborhood socioeconomic characteristics (neighborhood income, educational level, unemployment rate), in contrast, were not significantly associated with mortality. However, within advantaged neighborhoods, the importance of individual income and education for mortality was increased relative to disadvantaged neighborhoods. The latter findings may direct health policy aimed at reducing health inequalities.

The north-south gradient in health: analytic applications for public health.

Health in the northern territories does not reach that of national standards. Investigations in these areas are hampered by small population size, which limits both the identification of local health problems as well as the planning and prioritizing of prevention and interventions. We report on health deficiencies of the northern territories and illustrate how our analytic applications supplement traditional approaches to benefit public health objectives. We reveal that life expectancy in Northern Canada has increased such that health deficiencies between the North and South have decreased substantially, although they still persist at a high level. The current health status of Northwest Territories residents approximates that of Canadians 15 to 25 years ago. In addition, while chronic diseases were previously less of a concern for Northwest Territories residents, they show increasing trends in importance. This is of particular significance in light of an aging population in the northern territories.

Incidence of cancer in Sydney and Cape Breton County, Nova Scotia 1979-1997.

The primary purpose of this study was to assess whether Sydney, Industrial Cape Breton County excluding Sydney (ICBxS) and Cape Breton County (CBCo) residents were at increased risk for cancer compared to Nova Scotia (NS) residents over five-year periods during 1979 through 1997. Gender-stratified, age-standardized cancer incidence rates were calculated following the direct method. All-cause rates were higher for female and male residents of Sydney, ICBxS and CBCo compared to NS based upon both municipality and postal code methods of residence classification. A sensitivity analysis of residential coding yielded a high degree of consistency for all geographies except Sydney, limiting comparisons of Sydney rates with other local geographies except where consistencies were observed. The results of this ecological study support the need for further analysis of factors contributing to the increased risk for cancer in CBCo.

Secular trends in the survival of HIV-infected homosexual men in Amsterdam and Vancouver estimated from a death-included CD4-staged Markov model.

BACKGROUND: The purpose of this study was to investigate secular trends in waiting times in CD4-based stages of human immunodeficiency virus (HIV) disease progression in two cohorts of homosexual men, one in Vancouver and one in Amsterdam. All HIV-positive men with two or more CD4 counts in their AIDS-free period between 1 January 1985 and 1 January 1997 were included in this study. Data regarding clinical AIDS diagnoses (using the 1987 Centers for Disease Control and Prevention [CDC] AIDS case definition) and death were collected through active follow-up, review of hospital records, and municipal/national registries. The Vancouver Lymphadenopathy-AIDS Study (VLAS), was started in November 1982 and had enrollment until December 1984. Both HIV-negative and HIV-positive men were followed at intervals of 3-6 months until 1986 and annually thereafter. The Amsterdam cohort study on HIV and AIDS (ACS) started in December 1984, has ongoing enrollment and follow-up of both HIV-negative and HIV-positive homosexual men. The HIV-positive men were followed at intervals of 3 months. METHODS: The CD4-based stage of an individual at each visit was determined using smoothed data. For each cohort and in each calendar time period, a CD4-based Markov model with death as the absorbing stage was fitted to the data. The parameters in this model were estimated using the method of maximum likelihood and confidence intervals were calculated using bootstrap methods. RESULTS: A total of 509 homosexual men participating in the VLAS were included in this study, providing 5356 visits. Some 292 men developed AIDS before 1 January 1997 and 239 died before this date. In all, 232 of the 239 deaths were AIDS related. Thirty-seven per cent of all visits were related to treatment. A total of 543 homosexual men participating in the ACS were included in this study, providing 10 043 visits; 277 men developed AIDS before 1 January 1997 and 250 died before this date. The date of AIDS diagnosis was known for 225 of the 250 deaths. Twenty per cent of all visits were related to treatment. We found that in both cohort studies the stage-specific waiting times were longer in the low CD4-based stages (stages 4, 5 and 6: i.e. CD4 count <500 cells per mm(3)) after March 1990 compared to waiting times before March 1990. The increase in mean waiting time in these stages with low CD4 count was 21%, 33% and 53%, respectively in the ACS and 20%, 2% and 29% in the VLAS. Because waiting times alone are not exclusive for progression in a reversible model we also calculated the stage-specific median incubation periods till death. Men spent considerably longer in these CD4-based stages after March 1990 compared to before March 1990. CONCLUSIONS: Data from these population-based cohort studies showed that HIV disease progression in the calendar period where treatment was administered was slower for individuals in stages with low CD4 counts. We found no evidence for shortening of the incubation period that may have appeared from increasing virulence of the HIV in the population.

Inequalities in health. Analytic approaches based on life expectancy and suitable for small area comparisons.

STUDY OBJECTIVE: Simple measures of inequalities in health are proposed to facilitate the work of health policy makers and to build on the understanding of health differences between populations. In addition, it is aimed to make these measures applicable for comparisons of small populations and subgroups. METHODS: Inequalities in health or health deficiencies were quantified as the difference between the life expectancy of the subgroup of interest and that of the national population. Health deficiencies were divided into disease specific components by partial application of cause eliminated life table methods. To manage small numbers and to depict time trends, locally weighted regression smoothing was applied. Confidence intervals were constructed through Monte Carlo simulations. APPLICATIONS AND COMPARISONS: The proposed approaches were applied to the health situation in Cape Breton County, Nova Scotia, Canada, and disclosed the significance of different diseases and distinct patterns between communities. The proposed measures were also compared with the traditionally used standardised mortality rates and ratios. Here, the proposed measures appeared beneficial in that they are easier to comprehend and that they provide time trends and more robust estimates. CONCLUSIONS: The above advantages make the proposed approaches beneficial to health policy makers and epidemiologists. The approaches may also be incorporated in economic evaluations as well as in more sophisticated public health models.