Search

Stress research in youth typically considers either the autonomic nervous system or HPA axis. However, these systems are highly coordinated and physically interconnected. We examined whether the inter-relation between cardio-autonomic and HPA axis measures was better associated with perceived stress than their singular associations. Children and adolescents ( N = 201) collected saliva samples to measure cortisol (AUC AG , AUC I , maximum), wore an electrocardiogram monitor for 24 h to derive heart rate variability (HRV; LF, HF, LF/HF ratio), and completed the Perceived Stress Scale. The interaction between sympathovagal modulation (LF, LF/HF ratio) and cortisol awakening response (AUC AG , AUC I , maximum) explained significantly greater variance in perceived stress than either stress system alone. Higher sympathovagal modulation combined with higher cortisol awakening response was associated with greater perceived stress. Findings suggest that the inter-relation between cardio-autonomic and HPA axis activity may advance our understanding of how stress impacts health. [ABSTRACT FROM AUTHOR]

Objective To examine the effects of provincial income inequality (disparity between rich and poor), independent of provincial income and family socioeconomic status, on multiple adolescent health outcomes. Methods Participants (aged 12–17 years; N = 11,899) were from the Canadian National Longitudinal Survey of Children and Youth. Parental education, household income, province income inequality, and province mean income were measured. Health outcomes were measured across a number of domains, including self-rated health, mental health, health behaviors, substance use behaviors, and physical health. Results Income inequality was associated with injuries, general physical symptoms, and limiting conditions, but not associated with most adolescent health outcomes and behaviors. Income inequality had a moderating effect on family socioeconomic status for limiting conditions, hyperactivity/inattention, and conduct problems, but not for other outcomes. Conclusions Province-level income inequality was associated with some physical and mental health outcomes in adolescents, which has research and policy implications for this age-group. [ABSTRACT FROM AUTHOR]

Summary: Compliance with awakening salivary sampling is important for precise measurement of the diurnal cortisol profile. During childhood and adolescence, developmental factors influence sampling upon awakening (awake0) due to school routine, sleep/wake patterns, and age related cortisol changes. In the present study, children and adolescents’ sampling compliance of awakening cortisol was evaluated using accelerometry. Children and adolescents (N =201; 45.3% female; 8–18 years; M age =12.68 years, SD =2.03) participating in the Healthy Heart Project collected saliva samples, wore a tri-axle accelerometer, and completed demographic questionnaires. Intra-class correlations derived to examine awake0 sampling compliance indicated children and adolescents were highly compliant (ICC =.98). In children, a delay in awake0 sampling was associated with a steeper diurnal slope (β =−.23, p =.037) and greater awake0 cortisol (β =.24, p =.024); this was not observed in adolescents. In summary, children and adolescents are compliant with awakening salivary sampling. Sampling delay, particularly in children, and time of awakening influenced measures of the diurnal cortisol profile. These findings inform future studies assessing the diurnal cortisol profile in children and adolescents. [Copyright &y& Elsevier]

Elevated blood pressure is associated with diminished pain sensitivity. While this finding is well established in adults, it is less clear when the relation between blood pressure and pain sensitivity emerges across the life course. Evidence suggests this phenomenon may exist during childhood. Children ( N = 309; 56% boys) aged 10-15 years and their parents participated. Blood pressure readings were taken during a resting baseline. Maximum pain intensity was rated using a visual analogue scale (rated 0-10) in response to a finger prick pain induction. Parent-measured resting blood pressure was inversely associated with boys' pain ratings only. Cross-sectionally, lower pain ratings were related to higher SBP, univariately. Longitudinally, pain ratings predicted higher DBP, even after controlling for covariates. Determining when and how the relation between blood pressure and pain sensitivity emerges may elucidate the pathophysiology of hypertension. [ABSTRACT FROM AUTHOR]

Summary: The diurnal cortisol profile has been implicated in multiple physical and mental health conditions in children and adolescents; however, current knowledge regarding the stability of the diurnal cortisol profile is largely based on adults. Developmental changes throughout childhood and adolescence warrant examination of the stability of the diurnal cortisol profile during this stage in the lifecourse. The aim of the present study was to conduct a comprehensive evaluation of the diurnal cortisol profile in children and adolescents. Participants (N =233; M =12.40, SD =1.83; 44.2% girls) in the Healthy Heart Project collected saliva samples, completed demographic questionnaires, and recorded bed and waking time. Intra-class correlations were calculated to evaluate the stability of aggregate and single sample measures of the diurnal cortisol profile. Total cortisol concentration (AUCTG, AUCAG) and maximum sample were the most stable cortisol measures (ICCavg =0.54). Dynamic measures (AUCI, slope; ICCavg =0.22) and other single sample measures (awake, lunch, dinner, bedtime, morning random, day random; ICCavg =0.28) were less stable. Of the developmentally relevant covariates tested, sleep duration, adrenarche, and time of awakening were most associated with cortisol values. Altogether, the diurnal cortisol profile yielded moderate to high stability in children and adolescents. These findings can inform methodological decisions regarding cortisol sampling protocols for children and adolescents. [ABSTRACT FROM AUTHOR]

Objective To investigate the role of acculturation, as measured by generational status, on body mass index (BMI) in a sample of Canadian youth. Methods Population-based data from the National Longitudinal Survey of Children and Youth were used. Participants were divided into 2 age ranges: children aged 6–11 years (n = 14,287) and adolescents aged 12–17 years (n = 12,155). Youth were classified into one of five generations of immigration: first-generation, second-generation, mixed-generation, third-generation, and Aboriginal. Parent- and self-report height and weight were used to calculate BMI Z-scores. Results Generation of immigration was significantly related to BMI Z-score in both childhood and adolescence. First-generation immigrants had more weight gain compared to other groups during adolescence, but not during childhood. Conclusions Acculturation, as measured by generation of immigration, is an important predictor of BMI in Canadian children and adolescents. [ABSTRACT FROM PUBLISHER]

Objective Determine how parental nutrition label use, label literacy, and nutrition knowledge may be associated with cardiovascular health in parents and their children. Design and Setting Cross-sectional analyses of 2006 data from the Healthy Heart Project in Montreal, Canada. Participants Among community recruited families, parents were predominantly mothers (n = 127 [80%]; mean age, 45.0 years) and half of their children were female (44%; mean age, 12.5 years). Main Outcome Measures Blood pressure, lipids, and weight. Nutrition label use, label literacy, and nutrition knowledge among parents were collected using existing scales. Analyses Multivariable linear regression models. Results Among parents, nutrition label use was associated with lower total cholesterol (B[SE] = −.53 [.20]; P = .009), lower low-density lipoprotein (B[SE] = −.57 [.21]; P = .007), and lower total cholesterol/high-density lipoprotein cholesterol ratio (B[SE] = −.82 [.30]; P = .008) but was not associated with adiposity. Among children, greater parental nutrition knowledge was associated with lower body mass index percentiles (B[SE] = −3.6 [1.49]; P = .02), lower waist circumference (B[SE] = −1.27 [.55]; P = .02), and lower percent body fat (B[SE] = −1.28 [.47]; P = .008). Parental nutrition label use or nutrition knowledge was not associated with children's lipids. Conclusions and Implications Parents with greater nutrition label use had more favorable lipids, but children's lipids were unaffected. Children of parents with greater nutrition knowledge had lower adiposity. Further research on the correlates of label use and health is needed. [ABSTRACT FROM AUTHOR]