Association of stigma, diabetes distress and self-efficacy with quality of life in adolescents with type 1 diabetes preparing to transition to adult care.

AIMS: In type 1 diabetes (T1D), psychosocial factors may impact quality of life (QOL) and clinical outcomes, but remain understudied, particularly during late adolescence. Our aim was to determine whether stigma, diabetes distress and self-efficacy are associated with QOL in adolescents with T1D as they are preparing to transition to adult care. METHODS: We conducted a cross-sectional study of adolescents (ages 16-17 years) with T1D participating in the Group Education Trial to Improve Transition (GET-IT) in Montreal, Canada. Participants completed validated questionnaires on stigma using the Barriers to Diabetes Adherence (BDA) stigma subscale, self-efficacy (Self-Efficacy for Diabetes Self-Management Measure [SEDM], score 1-10), diabetes distress (Diabetes Distress Scale for Adults with type 1 diabetes) and QOL (Pediatric Quality of Life Inventory [PedsQL] 4.0 Generic Core Scale and PedsQL 3.2 Diabetes Module). We examined associations of stigma, diabetes distress and self-efficacy with QOL using multivariate linear regression models adjusted for sex, diabetes duration, socioeconomic status and HbA1c. RESULTS: Of 128 adolescents with T1D, 76 (59%) self-reported having the diabetes-related stigma and 29 (22.7%) reported experiencing diabetes distress. Those with stigma had lower diabetes-specific and general QOL scores compared with those without stigma, and stigma and diabetes distress were both associated with lower diabetes-specific QOL and lower general QOL. Self-efficacy was associated with higher diabetes-specific and general QOL. CONCLUSIONS: Stigma and diabetes distress are associated with lower QOL, whereas self-efficacy is associated with higher QOL in adolescents with T1D preparing to transfer to adult care.

Diabetes duration, perceived comfort with self-management and glycaemic control in adolescents with type 1 diabetes: A cross-sectional study.

AIMS: Evidence is lacking on whether diabetes duration is associated with type 1 diabetes (T1D) self-management during late adolescence before transfer from paediatric to adult care. We examined associations of diabetes duration with dimensions of perceived comfort with diabetes self-management (self-efficacy, transition readiness, diabetes distress) and glycaemic control in late adolescence. METHODS: Using a cross-sectional design, we conducted a secondary analysis of baseline data of adolescents (ages 16-17 years) with T1D followed at paediatric diabetes academic hospitals in Montreal and enrolled in the Group Education Trial to Improve Transition (GET-IT-T1D). Participants completed validated questionnaires on self-efficacy (Self-Efficacy for Diabetes Self-Management Measure [SEDM], score 1 to 10), diabetes distress and transition readiness, as well as a haemoglobin (HbA1c) capillary blood test. Our primary outcome was self-efficacy. We examined associations of diabetes duration with self-efficacy, diabetes distress, transition readiness and HbA1c using linear and logistic regression models adjusted for sex, socioeconomic status, insulin pump use, glucose sensor use and psychiatric comorbidity. RESULTS: Of 203 adolescents with T1D, mean diabetes duration (SD) was 7.57 (4.44) years. Mean SEDM score was 6.83 (SD 1.62). Diabetes duration was not associated with self-efficacy, diabetes distress or transition readiness. Each additional year of diabetes duration was associated with 0.11% (95% CI, 0.05 to 0.16) higher HbA1c. CONCLUSIONS: Although diabetes duration is not associated with dimensions of perceived comfort with diabetes self-management, adolescents with longer diabetes duration are at risk for higher HbA1c and may need additional support to improve glycaemic control before transition to adult care.

The longitudinal effects of maternal parenting practices on children's body mass index z-scores are lagged and differential.

BACKGROUND: The longitudinal relation between parenting practices and styles with children's body mass index z-scores (zBMI) is poorly understood. Previous studies suggest the relationship may be complex, but small samples and short follow-ups diminish the strength of the evidence. The objectives of this study were to investigate whether the relationship is bidirectional, time-varying, and lagged using data from a large, representative birth cohort of Quebec children. METHODS: Data were from the Québec Longitudinal Study of Child Development (QLSCD), a prospective birth cohort (n = 1,602). The mothers' interactions with their children (at ages 6, 8, 10, and 12 years) were utilized in factor analysis to identify three latent parenting practices (disciplinarian, lenient, and responsive). The parenting practices were analyzed with K-means clustering to identify the parenting styles. The temporal and bidirectional relationships were assessed in a cross-lagged path analysis using a structural equation modelling framework. Mixed models controlling for age, sex, income, mother's education, and whether the participant was first-born were estimated. Missing data were handled with full information maximum likelihood. RESULTS: From the linear mixed models, greater lenient and responsive parenting practices were associated with higher zBMI (B = 0.03, p < 0.05) two years later. However, there was no evidence that the relationship was bidirectional nor that parenting style was predictive of children's zBMI. CONCLUSION: While mothers' parenting practices were unaffected by their children's zBMI, parental practices were predictive of future zBMI among their prepubertal children. More in-depth exploration of parenting practices and their potential impact on pediatric weight is needed.

Supporting and Incentivizing Peer Leaders for an Internet-Based Private Peer Community for Youths With Type 1 Diabetes: Social Network and Directed Content Analysis.

BACKGROUND: Youths with type 1 diabetes (T1D) frequently experience stigma. Internet-based peer communities can mitigate this through social support but require leaders to catalyze exchange. Whether nurturing potential leaders translates into a central role has not been well studied. Another issue understudied in such communities is lurking, the viewing of exchanges without commenting or posting. OBJECTIVE: We aimed to assess the centrality of the peer leaders we selected, trained, and incentivized within the Canadian Virtual Peer Network (VPN)-T1D. This is a private Facebook (Meta Platforms, Inc) group that we created for persons aged 14 to 24 years with T1D. We specifically sought to (1) compare a quantitative estimate of network centrality between peer leaders and regular members, (2) assess the proportions of network exchanges that were social support oriented, and (3) assess proportions of high engagement (posts, comments, reactions, and votes) and low engagement (lurking) exchanges. METHODS: We recruited peer leaders and members with T1D from prior study cohorts and clinics. We trained 10 leaders, provided them with a monthly stipend, and encouraged them to post on the private Facebook group we launched on June 21, 2017. We extracted all communications (posts, messages, reactions, polls, votes, and views) that occurred until March 20, 2020. We calculated each member's centrality (80% of higher engagement communications comprising posts, comments, and reactions plus 20% of members with whom they connected). We divided each member's centrality by the highest centrality to compute the relative centrality, and compared the mean values between leaders and members (linear regression). We calculated the proportions of communications that were posts, comments, reactions, and views without reaction. We performed content analysis with a social support framework (informational, emotional, esteem-related, network, and tangible support), applying a maximum of 3 codes per communication. RESULTS: VPN-T1D gained 212 regular members and 10 peer leaders over 33 months; of these 222 members, 26 (11.7%) exited. Peer leaders had 10-fold higher relative centrality than regular members (mean 0.53, SD 0.26 vs mean 0.04, SD 0.05; 0.49 difference; 95% CI 0.44-0.53). Overall, 91.4% (203/222) of the members connected at least once through posts, comments, or reactions. Among the 75,051 communications, there were 5109 (6.81%) posts, comments, and polls, 6233 (8.31%) reactions, and 63,709 (84.9%) views (lurking). Moreover, 54.9% (3430/6253) of codes applied were social support related, 66.4% (2277/3430) of which were informational (eg, insurance and travel preparation), and 20.4% (699/3430) of which were esteem related (eg, relieving blame). CONCLUSIONS: Designating, training, and incentivizing peer leaders may stimulate content exchange and creation. Social support was a key VPN-T1D deliverable. Although lurking accounted for a high proportion of the overall activity, even those demonstrating this type of passive participation likely derived benefits, given that the network exit rate was low. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/18714.

Trajectories of cardiorespiratory fitness from childhood to adolescence: Findings from the QUALITY cohort.

Estimate the shape and number of cardiorespiratory fitness (CRF) trajectories from childhood to adolescence; and verify whether CRF trajectory membership can be predicted by sex, biological maturation, body weight, body composition and physical activity (PA) in childhood. Data from QUALITY were used. Participants attended baseline (8-10 y old, n = 630) and follow-ups 2 years (n = 564) and 7 years (n = 359) after baseline. Group-based trajectory analysis for relative peak oxygen consumption (VO2peak, ml·kg-1·min-1) was performed. A multinomial logistic regression model was used to estimate the associations between baseline predictors and trajectory membership. Mean age of the 454 participants was 9.7 ± 0.9 years at baseline. Three distinct VO2peak trajectories were identified and all tended to decrease. They were labelled according to the starting point and slope. High-Decreasers were mostly boys, had lower body weight and fat-free mass index and higher PA levels at baseline (p < 0.05). Female sex and higher weight were associated with higher odds of being classified in the Low-Decreaser trajectory (OR = 74.03, 95%CI = 27.06-202.54; OR = 1.48, 95%CI = 1.36-1.60). Those with higher PA were less likely to be Low-Decreasers (OR = 0.96, 95%CI = 0.94-0.97). Sex, body weight and PA in childhood are important influencing factors of VO2peak (ml·kg-1·min-1) trajectories across adolescence.

Severe obesity and global developmental delay in preschool children: Findings from a Canadian Paediatric Surveillance Program study.

Background: The co-presentation of severe obesity (SO) and global developmental delay (GDD) in Canadian preschool children has not been examined. However, SO and GDD may require syndromic diagnoses and unique management considerations. Objectives: To determine (1) minimum incidence; (2) age of onset and risk factors; and (3) health care utilization for co-presenting SO and GDD. Methods: Through the Canadian Paediatric Surveillance Program (CPSP), a monthly form was distributed to participants from February 2018 to January 2020 asking for reports of new cases of SO and GDD among children ≤5 years of age. We performed descriptive statistics for quantitative questions and qualitative content analysis for open-ended questions. Results: Forty-seven cases (64% male; 51% white; mean age: 3.5 ± 1.2 years) were included. Age of first weight concern was 2.5 ± 1.3 years and age of GDD diagnosis was 2.7 ± 1.4 years. Minimum incidence of SO and GDD was 3.3 cases per 100,000 for ≤5 years of age per year. Identified problems included school and/or behavioural problems (n = 17; 36%), snoring (n = 14; 30%), and asthma/recurrent wheeze (n = 10; 21%). Mothers of 32% of cases (n = 15) had obesity and 21% of cases (n = 10) received neonatal intensive care. Microarray was ordered for 57% (n = 27) of children. A variety of clinicians and services were accessed. As reported by CPSP participants, challenges faced by families and health service access were barriers to care. Conclusion: Children with SO and GDD have multiple comorbidities, and require early identification and referral to appropriate services. These cases may also benefit from additional testing to rule out known genetic obesity syndromes.

A mediation analysis on the relationship between dietary glycemic load, obesity and cardiovascular risk factors in children.

BACKGROUND/OBJECTIVE: Adiposity may mediate the effect of dietary glycemic load (GL) on lipid profiles in children, as studies have shown an association between dietary GL and adiposity and between adiposity and lipid profiles. Our objective was to evaluate the role of adiposity as a mediator in the association between dietary GL and lipid profiles after 2 years. SUBJECTS/METHODS: The Quebec Adipose and Lifestyle InvesTigation in Youth study included 630 children, 8-10 years old at recruitment with at least one parent with overweight or obesity with 2-year follow-up. Three baseline 24-h dietary recalls were administered by a dietitian at baseline. Child and parent characteristics were obtained through direct measurement (blood lipids, anthropometrics) or questionnaires (socio-economic characteristics). Indicators of adiposity, including body mass index (BMI) z-score and percent body fat, were the mediators of interest. A conventional approach using the Baron and Kenny method was used. A causal approach using marginal structural models (MSM) was used to estimate the controlled direct effect. RESULTS: Mean age at baseline was 9.6 years and 33% were overweight or obese. Both methods revealed that the effect of GL on blood lipids was mediated by adiposity. The weighted MSM did not show evidence of a direct effect (TG: ß =;0.01, 95% CI = -0.01,0.02; HDL: ß = 0.005, 95%CI = -0.002,0.01), whereas the conventional method did for TG but not HDL (TG:ß = 0.04, 95%CI = 0.01,0.07; HDL: ß = -0.01, 95%CI = -0.03,0.01). CONCLUSION: Adiposity contributes substantially to the association between GL and blood lipids. The choice of approach for mediation analysis should be based on the fulfilment of conditions of each method.

Neighborhood built environment typologies and adiposity in children and adolescents.

BACKGROUND/OBJECTIVES: Neighborhoods are complex, multidimensional systems. However, the interrelation between multiple neighborhood dimensions is seldom considered in relation to youth adiposity. We created a neighborhood typology using a range of built environment features and examined its association with adiposity in youth. SUBJECTS/METHODS: Analyses are based on data from the QUALITY cohort, an ongoing study on the natural history of obesity in Quebec youth with a history of parental obesity. Adiposity was measured at baseline (8-10 years) and follow up, ~8 years later. Neighborhood features were measured at baseline through in-person neighborhood assessments and geocoded administrative data and were summarized using principal components analysis. Neighborhood types were identified using cluster analysis. Associations between neighborhood types and adiposity were examined using multivariable linear regressions. RESULTS: Five distinct neighborhood types characterized by levels of walkability and traffic-related safety were identified. At ages 8-10 years, children in moderate walkability/low safety neighborhoods had higher BMI Z-scores [ß: 0.41 (0.12; 0.71), p = 0.007], fat mass index [ß: 1.22 (0.29; 2.16), p = 0.010], waist circumference [ß: 4.92 (1.63; 8.21), p = 0.003], and central fat mass percentage [ß: 1.60 (0.04; 3.16), p = 0.045] than those residing in moderate walkability/high safety neighborhoods. Attenuated associations were observed between neighborhood types and adiposity 8 years later. Specifically, residents of moderate walkability/low safety neighborhoods had a higher FMI [ß: 1.42 (-0.07; 2.90), p = 0.062], and waist circumference [ß: 5.04 (-0.26; 10.34), p = 0.062]. CONCLUSIONS: Neighborhoods characterized by lower traffic safety appear to be the most obesogenic to children, regardless of other walkability-related features. Policies targeting neighborhood walkability for children may need to prioritize vehicular traffic safety.

Maternal autoimmune disease and risk of hospitalization for autoimmune disease, allergy, and cancer in offspring.

BACKGROUND: Children whose mothers have autoimmune disease may be at risk of developing immune-mediated disorders. We assessed the association between maternal autoimmune disease and risk of autoimmune disease, allergy, and cancer in offspring. METHODS: We analyzed a cohort of 1,011,623 children born in Canada between 2006 and 2019. We identified mothers who had autoimmune diseases and assessed hospitalizations for autoimmune disease, allergy, and cancer in offspring between birth and 14 years of age. We estimated hazard ratios (HR) for the association of maternal autoimmune disease with child hospitalization in adjusted Cox regression models. We used within-sibling analysis to control for genetic and environmental confounders. RESULTS: A total of 20,354 children (2.0%) had mothers with an autoimmune disease. Compared with no autoimmune disease, maternal autoimmune disease was associated with the risk of childhood hospitalization for autoimmune disease (HR 1.96, 95% CI 1.66-2.31) and allergy (HR 1.30, 95% CI 1.21-1.40), but was not significantly associated with cancer (HR 1.31, 95% CI 0.96-1.80). Type 1 diabetes, celiac disease, inflammatory arthritis, and systemic lupus erythematosus were among specific maternal autoimmune diseases most strongly associated with childhood hospitalization for autoimmune disease and allergy. The associations disappeared after controlling for genetic and environmental confounders in the within-sibling analysis. CONCLUSIONS: Maternal autoimmune disease is associated with an increased risk of autoimmune disease and allergy hospitalization in offspring, but the relationship appears to be confounded by genetic and environmental factors. Prenatal exposure to immunologic or pharmacologic products is not likely a direct cause of immune-mediated disease in children.

Associations of neighborhood walkability with moderate to vigorous physical activity: an application of compositional data analysis comparing compositional and non-compositional approaches.

BACKGROUND: We compared the relation between neighborhood features and moderate to vigorous physical activity (MVPA) using linear regression analysis and the more novel compositional data analysis (CoDA). Compositional data analysis allows us to take the time children allocate to different movement behaviours during a 24-hour time period into account. METHODOLOGY: Data from youth participants (n = 409) in the QUALITY (QUebec Adipose and Lifestyle InvesTigation in Youth) cohort were included. Time spent in MVPA, light physical activity, sedentary behavior, and sleep ("24-hour movement behaviours") was measured using accelerometers. Neighborhood data were collected using a geographic information system and through direct observation. In CoDA models, we used orthogonal logratio coordinates, which allows for the association of neighbourhood walkability with MVPA to be estimated with respect to the average composition of all other behaviours within a 24-hour time frame. In baseline linear regression models, MVPA was regressed cross-sectionally on neighborhood walkability. All models were stratified by sex, and controlled for BMI z-scores, pubertal development, seasonal variation, parental education, and neighbourhood safety. RESULTS: Based on CoDA, girls who lived in more walkable neighborhoods had 10% higher daily MVPA (95% CI: 2%, 19%), taking into account all other movement behaviours. Based on linear regression, girls who resided in more walkable neighborhoods engaged in 4.2 (95% confidence interval [CI]: 1.2, 6.6) more minutes of MVPA per day on average than girls residing in less walkable neighborhoods. CONCLUSIONS: Unlike with traditional linear models, all movement behaviours were included in a single model using CoDA, allowing for a more complete picture of the strength and direction of the association between neighbourhood Walkability and MVPA. Application of CoDA to investigate determinants of physical activity provides additional insight into potential mechanisms and the ways in which people allocate their time.

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.

Validation of desk-based audits using Google Street View® to monitor the obesogenic potential of neighbourhoods in a pediatric sample: a pilot study in the QUALITY cohort.

BACKGROUND: The suitability of geospatial services for auditing neighbourhood features relevant to pediatric obesity remains largely unexplored. Our objectives were to (i) establish the measurement properties of a desk-based audit instrument that uses Google Street View ® to assess street- and neighbourhood-level features relevant to pediatric obesity (QUALITY-NHOOD tool, the test method) and (ii) comment on its capacity to detect changes in the built environment over an 8-year period. In order to do so, we compared this tool with an on-site auditing instrument (the reference method). METHODS: On-site audits of 55 street- and neighbourhood-level features were completed in 2008 in 512 neighbourhoods from the QUALITY cohort study. In 2015, both repeat on-site and desk-based audits were completed in a random sample of 30 of these neighbourhoods. RESULTS: Agreement between both methods was excellent for almost all street segment items (range 91.9-99.7%), except for road type (81.0%), ads/commercial billboards (81.7%), road-sidewalk buffer zone (76.1%), and road-bicycle path buffer zone (53.3%). It was fair to poor for perceived quality, safety and aesthetics items (range 59.9-87.6%), as well as for general impression items (range 40.0-86.7%). The desk-based method over-detected commercial billboards and road-sidewalk buffer zone, and generally rated neighbourhoods as less safe, requiring more effort to get around, and having less aesthetic appeal. Change detected over the 8-year period was generally similar for both methods, except that the desk-based method appeared to amplify the increase in the number of segments with signs of social disorder. CONCLUSIONS: The QUALITY-NHOOD tool is deemed adequate for evaluating and monitoring changes in pedestrian- and traffic-related features applicable to pediatric populations. Applications for monitoring the obesogenic nature of neighbourhoods appear warranted.

Body Mass Index Z Score vs Weight-for-Length Z Score in Infancy and Cardiometabolic Outcomes at Age 8-10 Years.

OBJECTIVES: To confirm that World Health Organization weight-for-length z scores (zWFL) and World Health Organization body mass index z scores (zBMI) in infancy are associated with adiposity and cardiometabolic measures at 8-10 years old and to compare the predictive ability of the 2 methods. STUDY DESIGN: zWFL and zBMI at 6, 12, and 18 months of age were computed using data extracted from health booklets, among participants in the Québec Adipose and Lifestyle InvesTigation in Youth prospective cohort (n = 464). Outcome measures at 8-10 years included adiposity, lipid profile, blood pressure, and insulin dynamics. The relationships between zWFL, zBMI, and each outcome were estimated using multivariable linear regression models. Outcome prediction at 8-10 years was compared between the 2 methods using eta-squared and the Lin concordance correlation coefficient. RESULTS: zWFL and zBMI were associated with all measures of adiposity at 8-10 years. Associations with other cardiometabolic measures were less consistent. For both zWFL and zBMI across infancy, eta-squared were highly similar and the Lin coefficients were markedly high (≥0.991) for all outcomes. CONCLUSIONS: There was no evidence that zBMI and zWFL in infancy differed in their ability to predict adiposity and cardiometabolic measures in childhood. This lends support to the sole use of zBMI for growth monitoring and screening of overweight and obesity from birth to 18 years. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03356262.

Self-reported weight loss attempts and weight-related stress in childhood: Heightening the risk of obesity in early adolescence.

OBJECTIVE: Weight loss attempts occur as early as childhood. The impacts of weight loss attempts and weight-related stress on the occurrence of obesity during childhood remain unknown. We aimed to: (a) assess the prevalence of self-reported weight loss attempts and weight-related stress in 8-10 year-old children and (b) determine associations with adiposity 2 years later. METHOD: Data were collected from a cohort study of 564 Canadian children aged 8-10 years, having one or both biological parents with obesity (Quebec Adipose and Lifestyle Investigation in Youth cohort). Self-reported weight loss attempts and weight-related stress were assessed at baseline in the child's questionnaire. Adiposity was measured at baseline and 2 years later using body mass index z-scores (zBMI), waist-to-height ratio (WHtR), and percentage of body fat (%BF) obtained from dual-energy x-ray absorptiometry. Linear and logistic regression analyses were used while adjusting for potential confounders. RESULTS: Forty-eight percent of children reported previous weight loss attempts and 20% reported weight-related stress. Self-reported weight loss attempts and weight-related stress were associated with higher zBMI, WHtR, and %BF 2 years later in adjusted models, although estimates were attenuated when including baseline adiposity measures. Self-reported weight loss attempts, but not weight-related stress, increased the risk of becoming overweight among children who were normal weight at baseline. DISCUSSION: Weight loss attempts are prevalent in children with parental obesity. Children reporting weight loss attempts and weight-related stress tend to have higher adiposity 2 years later and are more likely to become overweight.

Which healthy lifestyle habits mitigate the risk of obesity and cardiometabolic risk factors in Caucasian children exposed to in utero adverse gestational factors?

BACKGROUND AND AIMS: This study explored if lifestyle habits [physical activity (PA), sleep duration, intake of fruits and vegetables, grains, and dairy products] can moderate the positive associations between prenatal exposure to suboptimal gestational factors (SGF: i.e. gestational diabetes mellitus, hypertensive disorders during pregnancy, maternal smoking during pregnancy) and obesity and cardiometabolic risk factors in children. METHODS AND RESULTS: Data from the "Quebec Adiposity and Lifestyle Investigation in Youth" (QUALITY) study collected between 2005 - 2008 in Montreal and Quebec City, were used. Analyses included a sample of 619 children aged 8-10 years. Children's PA and sleep duration were obtained using an accelerometer and daily servings of food were assessed using three 24 h diet recalls. Moderation analyses were performed to investigate if each lifestyle habit, in all children, and in boys and girls, could reduce the positive associations between SGF, and obesity and cardiometabolic risk factors. High LPA duration was protective against low levels of HDL cholesterol in boys who were exposed to more than one SGF (p = 0.005). Sleep duration did not have a protective effect respectively against high waist circumference and obesity in children and girls who were prenatally exposed to maternal smoking during pregnancy. Diet and MVPA did not moderate the positive associations between SGF, obesity and cardiometabolic risk factors in children. CONCLUSION: Among the three lifestyle habits, only LPA had a protective effect against low levels of HDL-cholesterol in boys. More studies are needed to confirm these results to inform future lifestyle intervention in this population.

Comparison of two carbohydrate intake strategies to improve glucose control during exercise in adolescents and adults with type 1 diabetes.

BACKGROUND AND AIMS: During aerobic physical activity (PA), hypoglycemia is common in people with type 1 diabetes (T1D). Few studies have compared the effectiveness of different carbohydrate (CHO) intake strategies to prevent PA-induced hypoglycemia. Our objective was to compare the efficacy of two CHO intake strategies, same total amount but different CHO intake timing, to maintain glucose levels in the target range (4.0-10.0 mmol/L) during PA in people with T1D. METHODS AND RESULTS: An open-label, randomized, crossover study in 33 participants (21 adults; 12 adolescents). Participants practiced 60 min PA sessions (ergocyle) at 60% VO2peak 3.5 h after lunch comparing an intake of 0.5 g of CHO per kg of body weight applied in a pre-PA single CHO intake (SCI) or in a distributed CHO intake (DCI) before and during PA. The percentage of time spent in glucose level target range during PA was not different between the two strategies (SCI: 75 ± 35%; DCI: 87 ± 26%; P = 0.12). Hypoglycemia (<4.0 mmol/L) occurred in 4 participants (12%) with SCI compared to 6 participants (18%) with DCI (P = 0.42). The SCI strategy led to a higher increase (P = 0.01) and variability of glucose levels (P = 0.04) compared with DCI. CONCLUSIONS: In people living with T1D, for a 60 min moderate aerobic PA in the post-absorptive condition, a 0.5 g/kg CHO intake helped most participants maintain acceptable glycemic control with both strategies. No clinically significant difference was observed between the SCI and DCI strategies. ClinicalTrials.gov Identifier: NCT03214107 (July 11, 2017).

Cesarean delivery and risk of hospitalization for autoimmune disorders before 14 years of age.

It is supposed that cesarean birth is implicated in the development of autoimmunity. We evaluated the association between cesarean delivery and the risk of hospitalization for autoimmune disease in children up to 14 years of age. We performed a longitudinal cohort study of 934,873 children born between 2006 and 2019 in Quebec, Canada. The main exposure measure was cesarean delivery versus vaginal delivery (spontaneous or induced). Outcomes included hospitalization for type 1 diabetes, celiac disease, or other autoimmune disorders before 14 years of age. We used Cox regression models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between cesarean delivery and hospitalization for autoimmune disorders, adjusted for patient characteristics. A total of 248,963 children (27%) were delivered by cesarean. Median length of follow-up was 7.4 years. The hospitalization rate for autoimmune disorders was 69.1 per 100,000 person-years for cesarean and 65.9 per 100,000 person-years for vaginal delivery. Cesarean delivery was not associated with autoimmune disorders overall (HR 1.02, 95% CI 0.96-1.10). There was no association with type 1 diabetes (HR 1.00, 95% CI 0.85-1.17), celiac disease (HR 0.86, 95% CI 0.71-1.04), inflammatory bowel disease (HR 1.15, 95% CI 0.88-1.49), or idiopathic thrombocytopenic purpura (HR 1.01, 95% CI 0.82-1.25). Cesarean delivery was not associated with autoimmune disorders at different ages.Conclusion: This study suggests that cesarean delivery is not associated with the risk of hospitalization for autoimmune disorders before 14 years of age. Delivery mode does not seem to mediate the risk of autoimmunity in childhood. What is Known: • Children born by cesarean may be at risk of abnormal immune development. • The association between cesarean delivery and risk of pediatric autoimmune disorders is unclear. What is New: • In this cohort study of over 900,000 children, cesarean delivery was not associated with the risk of hospitalization for a range of autoimmune disorders before 14 years of age. • Cesarean delivery may not be related to the development of autoimmunity.

Breastfeeding duration in infancy and dietary intake in childhood and adolescence.

Although several studies have focused on associations between breastfeeding and child obesity, few have focused on associations with dietary intake. We examined associations between breastfeeding duration in infancy and dietary intake in childhood and explored whether associations are still observed in adolescence. The QUALITY (QUebec Adipose and Lifestyle InvesTigation in Youth) cohort includes 630 children aged 8-10 years at baseline (T1) who have at least one parent with obesity. A follow-up assessment was done 7 years later (T2) when participants were aged 15-17 years (n=377). Non-exclusive breastfeeding duration was evaluated at T1 using a parent questionnaire (never, < 3 months, 3-6 months, > 6 months). Dietary intake was assessed at T1 and T2 using three 24-h diet recalls, namely daily servings of vegetables (≥ 2 vs < 2), fruits (≥ 2 vs < 2), vegetables and fruits combined (≥ 5 vs < 5), sugar-sweetened beverages (SSB) (none vs any), and an overall diet quality index (DQI-I) (good vs poor). Multiple logistic regressions, adjusted for age, sex and total kilocalorie intake of the child, for age and body mass index of the mother, and for parental education and income were used. Compared to children breastfed > 6 months (reference group), those never breastfed or breastfed for 3-6 months were 42% (OR = 0.58, 95% CI: 0.34-0.96) and 38% (OR = 0.62, 95% CI: 0.39-1.00) less likely to consume ≥ 2 servings of vegetables per day at 8-10 years, respectively, while no association was found for those breastfed < 3 months. Compared to children breastfed > 6 months, those never breastfed were 1.8 times more likely to drink any SSB (OR = 1.82, 95% CI: 1.03-3.22). No associations were found for other diet indicators, and associations observed in childhood were no longer found by adolescence. In this cohort, breastfeeding was associated with greater vegetable intake and the avoidance of SSB in childhood, but not in adolescence, nor were associations found for fruit intake or overall diet quality.

Substrate Oxidation Is Altered by Obesity During Submaximal Cycling in Prepubertal and Early Pubertal Children: A Quality Study.

BACKGROUND: To examine substrate oxidation in prepubertal and early pubertal children as a function of body weight, body composition, and sex during an exhaustive cycling test. METHODS: This study included 320 children in prepubertal and early puberty (Tanner stage 1 or 2; n = 188 males) who completed a minimum of 4 stages (2-5 min/stage) of an adapted version of the McMaster exhaustive exercise protocol on an upright cycle ergometer. Substrate utilization, relative to individual VO2peak, was determined using VO2 and VCO2 data, obtained with breath-by-breath gas analysis during exercise. RESULTS: Both peak (mg/kg lean body mass·min) and submaximal lipid oxidation (mg/kg lean body mass·min) were highest (P < .01) in children with healthy weight (HW), then overweight, and lowest in obese (OB). Both females with HW (compared with males with HW) and females with OB (compared with males with OB) had higher (P < .01) peak and submaximal lipid oxidation. In children with OB, fat-free mass correlated positively (P < .01) with submaximal lipid oxidation (r = .50). In contrast, in children with HW and overweight, fat-free mass correlated positively (P < .01) with carbohydrate oxidation (r = .52 and r = .47, respectively). CONCLUSION: Obesity during childhood may alter substrate oxidation during exercise. These results may have implications in the implementation of exercise programs in prepubertal or early puberty to control adiposity.

Reduction in ambulatory distance from childhood through adolescence: The impact of the number and length of steps.

BACKGROUND: The aim of this study was to explore the relationship between ambulatory distance with steps/day and increased step length as children age. METHODS: This is a prospective cohort study. Forty-five children from the QUALITY cohort were assessed at childhood (baseline) and seven years later during adolescence (follow-up). Daily step count was evaluated by accelerometry, step length by a standardized test, and daily ambulatory distance was calculated based on step count and length. RESULTS: Children grew by an average of 0.33 m from childhood to adolescence (p < 0.001). The daily ambulatory distance decreased by an average 3008 m from childhood to adolescence (p < 0.001). Step length increased an average of 0.10 m (p < 0.001) from childhood to adolescence, while the number of steps taken decreased by an average of 5549 steps (childhood to adolescence) (p < 0.001). The change in the number of steps between childhood and adolescence represents 84.6% of the change in the ambulatory distance while the change in step length explained an additional 13.0. CONCLUSIONS: The decrease in the ambulatory distance from childhood to adolescence was strongly explained by the decrease in step count; however the increase in step length should not to be neglected.