Health outcomes among children of immigrant mothers in the Quebec birth cohort

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal

Features of neighbourhood environments associated with obesity and related health behaviours in children: using multiple statistical approaches to identify obesogenic environments

Contexte: L'obésité chez les jeunes représente aujourd’hui un problème de santé publique à l’échelle mondiale. Afin d’identifier des cibles potentielles pour des stratégies populationnelles de prévention, les liens entre les caractéristiques du voisinage, l’obésité chez les jeunes et les habitudes de vie font de plus en plus l’objet d’études. Cependant, la recherche à ce jour comporte plusieurs incohérences. But: L’objectif général de cette thèse est d’étudier la contribution de différentes caractéristiques du voisinage relativement à l’obésité chez les jeunes et les habitudes de vie qui y sont associées. Les objectifs spécifiques consistent à: 1) Examiner les associations entre la présence de différents commerces d’alimentation dans les voisinages résidentiels et scolaires des enfants et leurs habitudes alimentaires; 2) Examiner comment l’exposition à certaines caractéristiques du voisinage résidentiel détermine l’obésité au niveau familial (chez le jeune, la mère et le père), ainsi que l’obésité individuelle pour chaque membre de la famille; 3) Identifier des combinaisons de facteurs de risque individuels, familiaux et du voisinage résidentiel qui prédisent le mieux l’obésité chez les jeunes, et déterminer si ces profils de facteurs de risque prédisent aussi un changement dans l’obésité après un suivi de deux ans. Méthodes: Les données proviennent de l’étude QUALITY, une cohorte québécoise de 630 jeunes, âgés de 8-10 ans au temps 1, avec une histoire d’obésité parentale. Les voisinages de 512 participants habitant la Région métropolitaine de Montréal ont été caractérisés à l’aide de : 1) données spatiales provenant du recensement et de bases de données administratives, calculées pour des zones tampons à partir du réseau routier et centrées sur le lieu de la résidence et de l’école; et 2) des observations menées par des évaluateurs dans le voisinage résidentiel. Les mesures du voisinage étudiées se rapportent aux caractéristiques de l’environnement bâti, social et alimentaire. L’obésité a été estimée aux temps 1 et 2 à l’aide de l’indice de masse corporelle (IMC) calculé à partir du poids et de la taille mesurés. Les habitudes alimentaires ont été mesurées au temps 1 à l'aide de trois rappels alimentaires. Les analyses effectuées comprennent, entres autres, des équations d'estimation généralisées, des régressions multiniveaux et des analyses prédictives basées sur des arbres de décision. Résultats: Les résultats démontrent la présence d’associations avec l’obésité chez les jeunes et les habitudes alimentaires pour certaines caractéristiques du voisinage. En particulier, la présence de dépanneurs et de restaurants-minutes dans le voisinage résidentiel et scolaire est associée avec de moins bonnes habitudes alimentaires. La présence accrue de trafic routier, ainsi qu’un faible niveau de prestige et d’urbanisation dans le voisinage résidentiel sont associés à l’obésité familiale. Enfin, les résultats montrent qu’habiter un voisinage obésogène, caractérisé par une défavorisation socioéconomique, la présence de moins de parcs et de plus de dépanneurs, prédit l'obésité chez les jeunes lorsque combiné à la présence de facteurs de risque individuels et familiaux. Conclusion: Cette thèse contribue aux écrits sur les voisinages et l’obésité chez les jeunes en considérant à la fois l'influence potentielle du voisinage résidentiel et scolaire ainsi que l’influence de l’environnement familial, en utilisant des méthodes objectives pour caractériser le voisinage et en utilisant des méthodes statistiques novatrices. Les résultats appuient en outre la notion que les efforts de prévention de l'obésité doivent cibler les multiples facteurs de risque de l'obésité chez les jeunes dans les environnements bâtis, sociaux et familiaux de ces jeunes.Background: Childhood obesity currently poses a major public health challenge worldwide. In an attempt to identify potential targets for population-based prevention strategies, neighbourhood environments are increasingly being investigated in relation to childhood obesity and its behavioural precursors. However, research to date is largely beset by inconsistencies in findings. Purpose: The overarching goal of this thesis is to investigate the contribution of different features of neighbourhood environments in relation to obesity and antecedent behaviours in children. Specific objectives are: 1) To examine associations between children’s residential and school neighbourhood food environments and their dietary intake and behaviours; 2) To examine shared exposure to features of residential neighbourhoods in relation to obesity among family triads (child, mother, and father) and among individual family members; 3) To identify specific combinations of individual, familial, and neighbourhood risk factors that best predict obesity in children, and determine whether these risk factor profiles also predict 2-year changes in obesity. Methods: Data were drawn from the QUALITY Cohort, a Quebec-based study of 630 children aged 8-10 years at baseline with a parental history of obesity. Baseline residential neighbourhood environments of 512 participants living in the Montreal Metropolitan Area were characterised using: 1) geographically linked census and administrative data computed for road network buffers centered on the residential and school locations; and 2) in-person neighbourhood observations conducted within the participants’ residential neighbourhoods. Neighbourhood measures included characteristics of the built, social, and food services environments. Obesity was determined using the body mass index (BMI) computed from measured weight and height at baseline and at follow up. Diet was measured using three 24-hour diet recalls at baseline. Different types of analyses were used including generalised estimating equations, multilevel regressions, and recursive partitioning. Results: Findings point to specific neighbourhood features that are associated with childhood obesity and diet. Most notably, increased availability of convenience stores and fast food restaurants within residential and school neighbourhoods is associated with poorer diets among children. High street-level traffic and low neighbourhood prestige and urban development in residential neighbourhoods are associated with obesity among family triads. Lastly, findings suggest that obesogenic neighbourhood environments characterised by socioeconomic disadvantage, fewer parks, and more convenience stores jointly predict childhood obesity within unique combinations of individual and familial risk factors. Conclusion: This thesis contributes to the literature on neighbourhood environments and childhood obesity by considering the influences of both residential and school neighbourhoods as well as familial environments, by objectively characterising neighbourhoods, and by using innovative statistical approaches. Findings furthermore support the notion that obesity prevention efforts should target multiple risk factors of childhood obesity within the built, social, and family environments of children

Identifying risk profiles for childhood obesity using recursive partitioning based on individual, familial, and neighborhood environment factors.

International audienceFew studies consider how risk factors within multiple levels of influence operate synergistically to determine childhood obesity. We used recursive partitioning analysis to identify unique combinations of individual, familial, and neighborhood factors that best predict obesity in children, and tested whether these predict 2-year changes in body mass index (BMI). Data were collected in 2005-2008 and in 2008-2011 for 512 Quebec youth (8-10 years at baseline) with a history of parental obesity (QUALITY study). CDC age- and sex-specific BMI percentiles were computed and children were considered obese if their BMI was ≥95th percentile. Individual (physical activity and sugar-sweetened beverage intake), familial (household socioeconomic status and measures of parental obesity including both BMI and waist circumference), and neighborhood (disadvantage, prestige, and presence of parks, convenience stores, and fast food restaurants) factors were examined. Recursive partitioning, a method that generates a classification tree predicting obesity based on combined exposure to a series of variables, was used. Associations between resulting varying risk group membership and BMI percentile at baseline and 2-year follow up were examined using linear regression. Recursive partitioning yielded 7 subgroups with a prevalence of obesity equal to 8%, 11%, 26%, 28%, 41%, 60%, and 63%, respectively. The 2 highest risk subgroups comprised i) children not meeting physical activity guidelines, with at least one BMI-defined obese parent and 2 abdominally obese parents, living in disadvantaged neighborhoods without parks and, ii) children with these characteristics, except with access to ≥1 park and with access to ≥1 convenience store. Group membership was strongly associated with BMI at baseline, but did not systematically predict change in BMI. Findings support the notion that obesity is predicted by multiple factors in different settings and provide some indications of potentially obesogenic environments. Alternate group definitions as well as longer duration of follow up should be investigated to predict change in obesity

Associations between weight loss attempts, weight-related stress and body image during childhood and adolescence in children with parental obesity

Background: Few longitudinal studies have investigated the role of weight-loss attempts or weight-related stress on body image during childhood. We examined whether weight-loss attempts and weight-related stress are associated with weight misperception and body dissatisfaction across childhood and adolescence. Methods: Data were drawn from the Quebec Adipose and Lifestyle InvesTigation in Youth (QUALITY) cohort of Canadian children with parental obesity (8–10 years: n = 630; 10–12 years: n = 564; 15–17 years: n = 377). We assessed weight-loss attempts and weight-related stress at baseline and first follow-up, and perceived and desired silhouettes at first and second follow-up with questionnaires. Weight misperception consisted of the difference in BMI z-score (zBMI) from the perceived silhouette and the measured zBMI. Body dissatisfaction consisted of the discordance between perceived and desired silhouettes. We estimated multivariable mixed-effects regression models adjusting for age, sex, pubertal stage, parental BMI and education, and sport-based teasing. Results: Weight loss attempts were associated with a higher weight misperception score (ever tried, beta [95% confidence intervals; CI]: 0.13 [0.01–0.24]) and with 2.13 times higher desire to be thinner (95% CI: 1.39–3.26) at the subsequent follow-up. Similarly, children stressed by their weight had a higher misperception score (beta [95% CI]: 0.15 [0.02–0.27]) and greater desire to be thinner at the next follow-up (odds ratio [95% CI]: 1.73 [0.999–3.00]). Conclusions: Weight-loss attempts and weight-related stress in children and adolescents are associated with weight misperception and body dissatisfaction, supporting empowerment and counseling focusing on healthy eating behaviors and a positive body image

Natural history and determinants of dysglycemia in Canadian children with parental obesity from ages 8–10 to 15–17 years : the QUALITY cohort

In children, the mechanisms implicated in deterioration of glucose homeostasis versus reversion to normal glucose tolerance (NGT) remain uncertain. We aimed to describe the natural history of dysglycemia from childhood to late adolescence and to identify its early determinants. We used baseline (8–10 years, n = 630), 1st follow-up (10–12 years, n = 564) and 2nd follow-up (15–17 years, n = 377) data from the QUALITY cohort of White Canadian children with parental obesity. Children underwent a 2-h oral glucose tolerance test at each cycle with plasma glucose and insulin measured at 0/30/60/90/120 min. American Diabetes Association criteria defined dysglycemia (impaired fasting glucose, impaired glucose tolerance or type 2 diabetes). Longitudinal patterns of insulin sensitivity and beta-cell function were estimated using generalized additive mixed models. Model averaging identified biological, sociodemographic and lifestyle-related determinants of dysglycemia. Of the children NGT at baseline, 66 (21%) developed dysglycemia without reverting to NGT. Among children with dysglycemia at baseline, 24 (73%) reverted to NGT. In children with dysglycemia at 1st follow-up, 18 (53%) later reverted to NGT. Among biological, sociodemographic and lifestyle determinants at 8–10 years, only fasting and 2-h glucose were associated with developing dysglycemia (odds ratio [95% CI] per 1 mmol/L increase: 4.50 [1.06; 19.02] and 1.74 [1.11; 2.73], respectively). Beta-cell function decreased by 40% in children with overweight or obesity. In conclusion, up to 75% of children with dysglycemia reverted to NGT during puberty. Children with higher fasting and 2-h glucose were at higher risk for progression to dysglycemia, while no demographic/lifestyle determinants were identified

Road, rail, and air transportation noise in residential and workplace neighborhoods and blood pressure (RECORD Study)

Associations between road traffic noise and hypertension have been repeatedly documented, whereas associations with rail or total road, rail, and air (RRA) traffic noise have rarely been investigated. Moreover, most studies of noise in the environment have only taken into account the residential neighborhood. Finally, few studies have taken into account individual/neighborhood confounders in the relationship between noise and hypertension. We performed adjusted multilevel regression analyses using data from the 7,290 participants of the RECORD Study to investigate the associations of outdoor road, rail, air, and RRA traffic noise estimated at the place of residence, at the workplace, and in the neighborhoods around the residence and workplace with systolic blood pressure (SBP), diastolic blood pressure (DBP), and hypertension. Associations were documented between higher outdoor RRA and road traffic noise estimated at the workplace and a higher SBP [+1.36 mm of mercury, 95% confidence interval (CI): +0.12, +2.60 for 65-80 dB(A) vs 30-45 dB(A)] and DBP [+1.07 (95% CI: +0.28, +1.86)], after adjustment for individual/neighborhood confounders. These associations remained after adjustment for risk factors of hypertension. Associations were documented neither with rail traffic noise nor for hypertension. Associations between transportation noise at the workplace and blood pressure (BP) may be attributable to the higher levels of road traffic noise at the workplace than at the residence. To better understand why only noise estimated at the workplace was associated with BP, our future work will combine Global Positioning System (GPS) tracking, assessment of noise levels with sensors, and ambulatory monitoring of BP

Transportation noise and annoyance related to road traffic in the French RECORD study.

International audience: Road traffic and related noise is a major source of annoyance and impairment to health in urban areas. Many areas exposed to road traffic noise are also exposed to rail and air traffic noise. The resulting annoyance may depend on individual/neighborhood socio-demographic factors. Nevertheless, few studies have taken into account the confounding or modifying factors in the relationship between transportation noise and annoyance due to road traffic. In this study, we address these issues by combining Geographic Information Systems and epidemiologic methods. Street network buffers with a radius of 500 m were defined around the place of residence of the 7290 participants of the RECORD Cohort in Ile-de-France. Estimated outdoor traffic noise levels (road, rail, and air separately) were assessed at each place of residence and in each of these buffers. Higher levels of exposure to noise were documented in low educated neighborhoods. Multilevel logistic regression models documented positive associations between road traffic noise and annoyance due to road traffic, after adjusting for individual / neighborhood socioeconomic conditions. There was no evidence that the association was of different magnitude when noise was measured at the place of residence or in the residential neighborhood. However, the strength of the association between neighborhood noise exposure and annoyance increased when considering a higher percentile in the distribution of noise in each neighborhood. Road traffic noise estimated at the place of residence and road traffic noise in the residential neighborhood (75th percentile) were independently associated with annoyance, when adjusted for each other. Interactions of effects indicated that the relationship between road traffic noise exposure in the residential neighborhood and annoyance was stronger in affluent and high educated neighborhoods. Overall, our findings suggest that it is useful to take into account (i) the exposure to transportation noise in the residential neighborhood rather than only at the residence, (ii) different percentiles of noise exposure in the residential neighborhood, and (iii) the socioeconomic characteristics of the residential neighborhood to explain variations in annoyance due to road traffic in the neighborhood