Treatment Effects on Psychophysiological Stress Responses in Youth With Obesity.

OBJECTIVE: Stress plays a central role in obesity development, but research on treatment options to tackle elevated stress levels in youth with obesity is scarce. The present study examined the impact of the Multidisciplinary Obesity Treatment (MOT; lifestyle intervention including physical exercise, healthy meals, and cognitive behavioral techniques) on physiological stress parameters in youth with obesity and assessed whether adding emotion regulation (ER) training on top of MOT is beneficial. METHODS: From an inpatient treatment center for obesity, 92 youngsters (mean [standard deviation] age = 12.50 [1.66] years, 43.5% boys) were randomly assigned to a control group (MOT) or experimental group (MOT + ER training). Before (T1) and after 12 weeks of treatment (T2), high-frequency heart rate variability (HF-HRV) and heart rate were measured at rest and during a stress induction (= psychophysiological reactivity). RESULTS: At T2, after MOT only, participants displayed a lower resting heart rate ( MT2/T1 = 74.7/78.6) and a reduced stress response (i.e., less decrease in HF-HRV [ MT2/T1 = -0.06/-0.01] and less increase in heart rate [ MT2/T1 = 0.03/0.06] after the stress induction). No further improvements were revealed after adding ER training. However, when considering the weight changes, the significant results in resting heart rate and HF-HRV and heart rate reactivity decreased in the control group, and additional improvements in psychophysiological parameters were discovered in the experimental group. CONCLUSIONS: The results suggest that MOT may effectively reduce physiological stress responses and also provide preliminary evidence for a potential additional effect of ER training. Further research in a larger sample with extended follow-up measurements is needed.

Examining systemic inflammation as a pathway linking peer victimization to depressive symptoms in adolescence.

BACKGROUND: Adolescents exposed to victimization are at an increased risk for a variety of adverse mental health outcomes, including depressive symptoms. Yet, the biological pathways underlying these associations remain poorly understood. Focusing on within-person processes, we examined whether low-grade systemic inflammation mediated the longitudinal associations between peer victimization and depressive symptoms in adolescence. METHODS: 207 adolescents (at baseline Mage = 12.69 years; SD = 0.49; 43.5% female) participated in a multi-wave longitudinal study, with assessments repeated every 6 months over 1.5 years. At each assessment wave, participants self-reported their peer victimization experiences and depressive symptoms. Dried blood spots were collected at each wave using a finger prick procedure to assay a key marker of low-grade systemic inflammation, interkeukin-6 (IL-6). Data were analyzed using random-intercept cross-lagged panel models. RESULTS: The cross-lagged paths from IL-6 to depressive symptoms were significant across all models and waves (ß12 = .13; ß23 = .12; ß34 = .08), indicating that when adolescents' levels of low-grade systemic inflammation were above their person-specific average, they reported increased levels of depressive symptoms in the subsequent months. However, no significant cross-lagged within-person associations emerged between peer victimization and either IL-6 or depressive symptoms. CONCLUSIONS: The findings provide no evidence for the hypothesized mediating role of inflammation in the within-person associations between peer victimization and depressive symptoms. Nevertheless, they extend prior research by indicating that elevated levels of low-grade systemic inflammation predict the development of depressive symptoms in adolescence.

Exploring the impact of lifestyle and environmental exposures on appetite hormone levels in children and adolescents: An observational study.

BACKGROUND: Appetite hormones are considered a promising target in fighting obesity as impaired appetite hormone levels have already been associated with obesity. However, further insights in the drivers of appetite hormone levels are needed. OBJECTIVES: In this study, we investigated the associations of fasting appetite hormone levels with lifestyle and environmental exposures in children and adolescents. METHODS: A total of 534 fasting blood samples were collected from children and adolescents (4-16y,50% boys) and appetite hormone levels (glucagon-like peptide-1 (GLP-1), peptide YY (PYY), pancreatic polypeptide (PP), leptin and ghrelin) were measured. Exposures included dietary quality (fiber-rich food intake, sugar propensity, fat propensity), psychosocial stress (happiness, negative emotions, negative life events and emotional problems), sleep duration, physical activity and environmental quality (long term black carbon (BC), particulate matter <2.5 µM (PM2.5), nitrogen dioxide (NO2) exposure, and green space in a 100 m and 2000 m radius around the residence). A multi-exposure score was calculated to combine all the exposures at study in one measure. Associations of individual exposures and multi-exposure score with appetite hormone levels were evaluated using linear mixed regression models adjusting for sex, age, socioeconomic status, waist-to-height ratio and multiple testing. RESULTS: GLP-1 was associated with air pollution exposure (NO2 ß* = -0.13, BC ß* = -0.15, PM2.5 ß* = -0.16, all p < 0.001). Leptin was associated with green space in a 100 m radius around the residence (ß* = -0.11; p = 0.002). Ghrelin was associated with negative emotions (active ghrelin ß* = -0.16; p = 0.04, total ghrelin ß* = -0.23; p = 0.0051) and happiness (active ghrelin ß* = 0.25; p < 0.001, total ghrelin ß* = 0.26; p < 0.001). Furthermore, total ghrelin levels were associated with the multi-exposure score, reflecting unhealthy exposures and lifestyle (ß* = -0.22; p = 0.036). DISCUSSION: Our findings provide new insights into the associations of exposures with appetite hormone levels, which are of high interest for preventive obesity research. Further research is crucial to reveal the underlying mechanisms of the observed associations.

Implementation of a minimally invasive cell culture system to measure the regulation of inflammation in a school-based sample of adolescents.

Dysregulated inflammation underlies many human diseases, and measures of responsiveness to activation, and sensitivity to inhibition, provide important information beyond baseline assessments of chronic inflammation. This study implements a simplified cell culture protocol in a school-based setting, using finger stick capillary blood collected from 333 adolescents (age 11.4-15.6 years) incubated with lipopolysaccharide (LPS). Median cytokine responses for IL6, IL1ß, and TNFα were 61.9, 26.2, and 11.2 pg/mL, respectively. Samples were also incubated with LPS and glucocorticoid (GC) to measure GC sensitivity. Median responses were reduced in the presence of GC inhibition for IL6 (20.3 pg/mL), IL1ß (10.5 pg/mL), and TNFα (3.3 pg/mL). Minimally invasive cell culture protocols provide novel opportunities for measuring inflammatory phenotypes in a wide range of non-clinical settings.

Changes in physical activity patterns from adolescence to young adulthood: the BELINDA study.

Physical activity (PA) is recognized as a marker of health. The aim was to investigate PA differences from adolescence to young adulthood. European adolescents included in the HELENA study were invited to participate in a follow-up study, 10 years later. The present study included 141 adults (25.0 ± 1.4 years) for whom valid accelerometer data were available in adolescence and adulthood. Changes in PA by sex, weight and maternal education level were explored with interactions. Time spent in sedentary activity, light PA (LPA) and moderate PA (MPA) increased by 39.1, 59.6 and 6.6 min/day, respectively, whereas the time spent in vigorous PA (VPA) decreased by 11.3 min/day compared with adolescent VPA (p < 0.05). Increases in MPA were greater on weekends compared with weekdays, but we found a greater decrease in VPA on weekdays compared with weekends. Moderate-to-vigorous PA (MVPA) decreased significantly on weekdays (-9.6 min/day; 95%CI, -15.9 to -3.4), while it increased on weekends (8.4 min/day; 95%CI, 1.9 to 14.8). Significant heterogeneity was found across sexes for VPA and MVPA, with a stronger decrease in VPA in males compared with females and a significant decrease in MVPA (-12.5 min/day; 95%CI, -20.4 to -4.5) in males but not in females (1.9 min/day; 95%CI, -5.5 to 9.2). No significant heterogeneity was found to be linked to maternal education level or weight, irrespective of PA level.  Conclusion: Our data suggest that the transition from adolescence to young adulthood is a critical period for lifestyle PA habits. A decline in VPA and an increasingly sedentary time were observed. The observed changes are worrying and may increase the risk of developing adverse health consequences later in life. What is Known: • The transition from adolescence to adulthood is marked by many life changes affecting lifestyle habits. Most studies tracking physical activity from adolescence to adulthood were done using PA questionnaires, which is a subjective method. What is New: • Our study bring first data on objective changes in PA patterns between adolescence and young adulthood, taking account of BMI, sex and maternal educational level. Our results suggest that the transition from adolescence to young adulthood is a critical period for lifestyle PA habits, especially for time spent on sedentary activities.

Interplay of physical activity and genetic variants of the endothelial lipase on cardiovascular disease risk factors.

BACKGROUND: The aim of this study was to investigate the association of endothelial lipase gene (LIPG) polymorphisms with cardiovascular disease (CVD) risk factors in adolescents and their interaction with physical activity. METHODS: Six polymorphisms of LIPG were genotyped in 1057 European adolescents (12-18 years old) enrolled in the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Study. CVD risk factors related to lipid profile, blood pressure, adiposity and glucose regulation were recorded. Physical activity was objectively measured by accelerometry. RESULTS: The major C allele of rs2000813, the minor T allele of rs2276269 and the minor G allele of rs9951026 were associated with lower levels of several CVD risk factors related to lipid profile. We also found a significant association of the TTACA LIPG haplotype (rs2000812, rs2000813, rs8093249, rs2276269 and rs9951026) with higher concentrations of low-density cholesterol and apolipoprotein B. Finally, the interaction between physical activity and the polymorphisms rs2000813, rs2276269 and rs9951026 had a significant influence on several CVD risk factors. CONCLUSIONS: LIPG polymorphisms were significantly associated with CVD risk factors in European adolescents. Interestingly, alleles of these polymorphisms were associated with a better cardiovascular profile in physically active adolescents only. High physical activity may reduce the development of CVD, modulating its genetic risk. IMPACT: Using gene-phenotype and gene × environment analyses, we detected associations between the endothelial lipase gene and cardiovascular risk factors, along with interactions with physical activity. This study shows that physical activity may modulate the influence of LIPG gene on cardiovascular risk in adolescents. These results bring insights into the mechanisms by which physical activity positively influences CVD in adolescents.

Indoor nature integration for stress recovery and healthy eating: A picture experiment with plants versus green color.

AIM: Urbanized environments may stimulate unhealthy food choices and stress. Several theories explain that exposure to green nature can counter these stress effects. Since we spend most time indoors, integrating nature in the interior could be a promising health promotion tool. Hence, we tested whether the beneficial effect of nature for stress recovery is also present in indoor settings via the use of plants or green colors, and whether it is applicable on eating behavior as a new outcome. METHODS: The 92 participants (18-30y, 16% men) were divided into four groups. Each viewed a 6-min slideshow with room pictures containing either green plants, green objects, greyscale plants or greyscale objects to allow distinction between color- and plant-effects. Group differences were tested for the perceived restorativeness scale, psychological recovery and eating behavior. To allow psychological recovery testing, participants were exposed to a stressor before the picture slideshow via the Trier Social Stress Test. The change of self-reports (stress, positive and negative affect) and psychophysiology (heart rate and vagal-induced heart rate variability RMSSD) post-slideshow versus pre-slideshow was checked. Eating behavior outcomes included change in hunger, craving, and food choice (for fruits, vegetables and snacks). RESULTS: From the four picture sets, the green plants pictures were reported as most mentally restorative and appeared most beneficial for post-stressor recovery of positive affect, but not for negative affect or stress recovery. The green plants group also had higher preference for vegetables and lower preference or craving for (unhealthy) snacks. Those significant group differences were mainly due to the presence of plants and only occasionally due to the green color. CONCLUSION: Indoor green plant pictures were associated with higher mental restorativeness and healthier food choices. Integrating plants in the interior seems to be a relevant health promotion approach, while applying green colors seems less relevant.

A multi-exposure approach to study telomere dynamics in childhood: A role for residential green space and waist circumference.

BACKGROUND: Telomeres are vulnerable to various environmental exposures and lifestyle factors, encompassed in the exposome. Recent research shows that telomere length is substantially determined early in life and that exposures in childhood may have important consequences in setting later life telomere length. OBJECTIVES: We explore in a child population the associations of 17 exposures with telomere length and longitudinal telomere change. METHODS: Children (2.8-10.3y at baseline, 51.3% boys) were followed-up for five to seven years. Relative telomere length was measured at baseline and follow-up using quantitative real-time PCR. Exposures and lifestyle factors included: body composition (body mass index and waist circumference), dietary habits (sugar- and fat-rich food intake, vegetables and fruit intake), psychosocial stress (events, emotions, behaviour), sleep duration, physical activity, and residential environmental quality (longterm black carbon, particulate matter exposure, and residential green space). Cross-sectional (n=182) and longitudinal (n=150) analyses were assessed using linear regression models, adjusting for age, sex, socioeconomic status and multiple testing. RESULTS: Our longitudinal analyses showed that higher residential green space at baseline was associated with (ß=0.261, p=0.002) lower telomere attrition and that children with a higher waist circumference at baseline showed a higher telomere attrition (ß=-0.287, p=0.001). These two predictors were confirmed via LASSO variable selection and correction for multiple testing. In addition, children with more unhealthy exposures at baseline had a significantly higher telomere attrition over the follow-up period compared to children with more healthy exposures (ß=-0.200, p=0.017). DISCUSSION: Waist circumference and residential green space were identified as predictors associated with telomere attrition in childhood. These results further support the advantages of a healthy lifestyle from early age onwards and the importance of a green environment to promote molecular longevity from childhood onwards.

Changes in (poly)phenols intake and metabolic syndrome risk over ten years from adolescence to adulthood.

BACKGROUND AND AIMS: (Poly)phenols might contribute to prevent cardiovascular disease, but limited prospective studies exist among adolescents. This study aimed to evaluate within-subject longitudinal changes in (poly)phenols intakes and food group contributors while also exploring the association with metabolic syndrome risk (MetS) during 10 years of follow up in European adolescents becoming young adults. METHODS AND RESULTS: In 164 participants (58% girls, 13-18 y at baseline) from Ghent, Zaragoza and Lille, longitudinal data (2006-2016) on (poly)phenol intake was retrieved via 2 or 3 24 h recalls. Linear and logistic longitudinal regression tested the association of (poly)phenols intake (total and classes) with Mets risk or its components (waist-height-ratio, HDL cholesterol, LDL cholesterol, triglycerides, blood pressure and insulin resistance index), adjusted for age, sex, country and other nutrient intakes. The total (poly)phenols intake was 421 ± 107 mg/day (192 mg/1000 kcal/day) at baseline, while 610 ± 101 mg/day (311 mg/1000 kcal/day) at follow-up. The three major food sources for (poly)phenols were 'chocolate', 'fruit and vegetable juices', 'cakes and biscuits' during adolescence and 'coffee', 'tea' and 'chocolate' during adulthood. Phenolic acid intake was associated with less LDL increase over time, while stilbene intake with a steeper increase in triglycerides over time. CONCLUSIONS: Differences in major (poly)phenols contributors over time were partially explained by age-specific dietary changes like increased coffee and tea during adulthood. Some significant (poly)phenols-MetS associations might argue for nutrition-based disease prevention during adolescence, especially since adolescents had low (poly)phenols intake.

Intervention strategies to promote healthy and sustainable food choices among parents with lower and higher socioeconomic status.

BACKGROUND: A global shift towards more healthy and sustainable diets is necessary for the prevention of obesity and chronic diseases, as well as for the growing pressure on our ecosystems. Given that parents are important actors in affecting dietary behaviors of their children, developing intervention strategies targeting families and their practices is promising to reach positive behavior change among children. Also, it is important to tailor these interventions to the needs of parents with different socioeconomic statuses (SES), given that health inequalities continue to grow. This study aims to investigate perspectives of lower and higher SES parents on the usability and acceptability of various innovative intervention strategies. METHODS: Fourteen focus groups and four individual interviews (n = 78, nlowerSES = 17; nhigherSES = 61) were conducted in Belgium. A semi-structured interview guide was used to facilitate the discussions. The interviews were recorded, transcribed, and analyzed via thematic content analysis using NVivo. RESULTS: To encourage healthy and sustainable food choices, interventions via online food shopping platforms and nudging strategies in grocery stores were mostly cited by higher SES parents, but these were less applicable for lower SES parents as they buy less online and mainly consider the price of products. Mobile applications that provide inspiration for healthy and sustainable recipes and easily accessible shopping lists received moderate support among lower and higher SES parents. Furthermore, both lower and higher SES parents showed interest in meal boxes delivered at home, but lower SES parents have not yet tried such meal boxes because of their higher prices. Still, both groups of SES parents mentioned many advantages of these meal boxes, such as the convenience and time-saving component, as well as the cooking inspiration aspect. CONCLUSION: Our study reveals the preferences of lower and higher SES parents for practical intervention strategies, providing insight in what features these strategies should have to be acceptable and useful. Hence, the findings can inform the development of a tailored family-based intervention strategy to improve parental food choices in favor of increased health and sustainability.

Determinants of healthy and sustainable food choices in parents with a higher and lower socioeconomic status: A qualitative study.

Establishing healthy and sustainable dietary habits in childhood is necessary for the prevention of obesity and chronic diseases, as well as for the growing pressure on our ecosystems. Considering that parents are the most important actors in affecting dietary behaviors of their children, and that there is a social gradient for obesity, this study aims to investigate differences in determinants of both healthy and sustainable food choices among parents with a higher and lower socioeconomic status (SES). Fifteen focus groups and four individual interviews (n = 78) with parents of children aged 6 to 12 were conducted in Belgium. A semi-structured interview guide based on a socioecological model was used. The interviews were recorded, transcribed and thematic content analysis was performed using NVivo 1.0. Findings indicate some differences in determinants of healthy and sustainable food choices among higher and lower SES parents. Generally, higher SES parents reported more barriers for sustainable than for healthy food choices. They showed more positive attitudes towards healthy than sustainable food choices, and reported low knowledge and self-efficacy to make sustainable food choices, while a lack of time was a barrier to cook both healthy and sustainable meals. Lower SES parents, like higher SES parents, showed more positive attitudes towards healthy food choices. They reported high prices and a lack of inspiration and skills as barriers for both food choices, while also being influenced by their cultural backgrounds. For both SES types of parents, children had a strong influence on their healthy and sustainable food choices. The findings suggest socioeconomic differences in determinants of healthy and sustainable food choices. Hence, these differences should be taken into account when developing intervention strategies to improve food choices in parents.

Adolescents' dietary polyphenol intake in relation to serum total antioxidant capacity: the HELENA study.

We evaluated the association between intake of total polyphenols, polyphenol classes and the 10 most consumed individual polyphenols with serum total antioxidant capacity (TAC) in 749 European adolescents (53% girls; 15% overweight; 12.5-17.5 years-old) from the cross-sectional HELENA study of 2006-2007. Dietary polyphenol intake was calculated from two non-consecutive 24-h recalls matched with the Phenol-Explorer database. Multilevel linear models examined the associations between dietary polyphenols and TAC. Polyphenol intake was rather low (median = 321mg/day; p25 = 158; p75 = 536) and TAC was comparable to other literature findings (median = 1.57 mmol/L; p25 = 1.45; p75 = 1.74). Total polyphenol intake, polyphenol classes and the top 10 compounds were not associated with TAC in a linear, quadratic or cubic way in partially or fully confounder-adjusted models. A direct anti-oxidative effect of dietary polyphenol intake was not observed in European adolescents. Polyphenol biomarkers and additional antioxidant measures are needed in future prospective studies to confirm these results.

Associations between hair and salivary cortisol, salivary alpha-amylase, and temperament dimensions among 3-6-year-olds.

Associations between hair cortisol concentration (HCC), diurnal salivary cortisol (sCort) and alpha-amylase (sAA), and temperament dimensions were examined among 3-6-year-old Finnish children (n = 833). Children's hair samples were collected at preschool, while parents collected five saliva samples from children during one weekend day and completed a questionnaire assessing child's temperament dimensions i.e. surgency, negative affectivity, and effortful control (HCC, n = 677; AUCg of sAA, n = 380; AUCg of sCort, n = 302; temperament dimensions, n = 751). In linear regression analysis, diurnal sCort associated positively with HCC, the association persisting after adjustments (ß 0.31, 95% CI 0.20-0.42). In logistic regression analysis, increasing scores in effortful control associated with higher likelihood of having high HCC (OR 1.47, 95% CI 1.07-2.03), the association slightly attenuating to non-significant after adjustments. Otherwise, no clear indication for associations between temperament and stress-related biomarkers were found.

Green nature effect on stress response and stress eating in the lab: Color versus environmental content.

INTRODUCTION: It is still unclear which green nature aspects can counteract psychosocial stress: the green color or rather the environmental content (=nature). Since stress is often stimulating excess/unhealthy food intake, we hypothesize that green nature also buffers stress-induced eating. This study analyzed the effects of green/nature pictures on restorativeness, stress reactivity/response and stress eating in the lab. METHODS: Before (5min) and after (8min) the Trier Social Stress Test, 81 participants (82% women, 19-30y) saw one of the four slideshows with nature or urban environments in green or black-white shades. Group differences were tested on Perceived Restorativeness Scale, five repeated measures of heart rate variability (HRV), salivary cortisol and mood, food wanting and snack buffet consumption. RESULTS: The four groups did not differ in background and baseline values. Reported restorative power was higher in the nature pictures than urban pictures with an even better attentional/happiness restoration capacity for green versus black-white nature, while green urban pictures might induce more stress feelings than black-white urban pictures. The stress time patterns confirmed successful stress induction. Most consistent during stress induction was a higher happiness recovery in the green nature group. Nature overall was somewhat beneficial compared to urban pictures by lower HRV and negative emotions reactivity, although this might be due to unfavorable effects of green urban pictures. In food intake or wanting, no differences existed. CONCLUSION: Nature pictures were estimated higher in restorative power and green nature pictures had a positive effect on happiness recovery. Thus for prevention, the environmental content (=nature) as such seems important while just a green color seemed not enough. Future research should examine the effect of green nature in realistic indoor settings and consider influence on fruit/vegetable intake instead of solely snacks.

Determinants of Physical Fitness in Children with Repaired Congenital Heart Disease.

The aim of this study was to determine factors associated with physical fitness (PF) in children who underwent surgery for congenital heart disease (CHD). Sixty-six children (7-14 years) who underwent surgery for ventricular septal defect (n = 19), transposition of great arteries (n = 22), coarctation of aorta (n = 10), and tetralogy of Fallot (n = 15) were included. All children performed PF tests: cardiorespiratory fitness, upper- and lower-limb muscle strength, speed, balance, and flexibility. Cardiac evaluation was done via echocardiography and cardiopulmonary exercise test. Factors related to child's characteristics, child's lifestyle, physical activity motivators/barriers, and parental factors were assessed. Linear regression analyses were conducted. The results showed no significant differences in physical activity (PA) level by CHD type. Boys had better cardiorespiratory fitness (difference = 1.86 ml/kg/min [0.51;3.22]) and were more physically active (difference = 19.40 min/day [8.14;30.66]), while girls had better flexibility (difference = - 3.60 cm [- 7.07;- 0.14]). Physical activity motivators showed an association with four out of six PF components: cardiorespiratory fitness, coefficient = 0.063 [0.01;0.11]; upper-limb muscle strength, coefficient = 0.076 [0.01;0.14]; lower-limb muscle strength, coefficient = 0.598 [0.07;1.13]; and speed, coefficient = 0.03 [0.01;0.05]. Age, sex, and motivators together reached a maximum adjusted R2 = 0.707 for upper-limb strength. Adding other possible determinants did not significantly increase the explained variance. Apart from age and sex as non-modifiable determinants, the main target which might improve fitness would be the introduction of an intervention which increases the motivation to be active.

Eating disorders and the risk of developing cancer: a systematic review.

PURPOSE: Evidence concerning eating disorders as risk toward developing cancer is sparse. Energy restriction might be cancer protective, while malnutrition, vomiting, laxative and substance use might stimulate cancer development. We examined whether individuals with an eating disorder (not restricted to anorexia nervosa) had a different risk of developing cancer. METHODS: A systematic search on Medline and Embase until 28th April 2020 identified relevant human original research publications, including all populations and all cancer types. RESULTS: From 990 records, 6 case reports and 9 cohorts were included. Some cohorts found a decreased breast (3/5 studies) or cervical (1/2) cancer risk, while an increased esophageal (2/3), liver (1/1), brain (1/1 in men) and respiratory (2/4) cancer risk, but other cancer risks were non-significant, and an increased mortality overall (1/2), from breast (1/1), female genital (1/1) and skin (1/1) cancer in eating disorder patients. The case reports further described esophageal cancer and leukemia. No clear statistical differences in cancer risk were found depending on eating disorder type, perhaps due to the small sample size (n = 1783 for other than anorexia nervosa). CONCLUSIONS: The literature on eating disorders and cancer risk is sparse with many gaps. Hormonal changes, sexual activity, nutritional status, vomiting and concomitant tobacco/alcohol abuse may explain increased/decreased cancer risk. Future large studies (now 1-366 cancer cases) that also include men (now 4.7%), bulimia nervosa (now 3.8%) and several cancer sites (now mainly breast cancer) are needed and should foresee longer follow-up time (now 5.4-15.2 years) and extensive confounder adjustment (now only age and sex). LEVEL OF EVIDENCE: Level I, systematic review.

Validated Ultra-High-Performance Liquid Chromatography Hybrid High-Resolution Mass Spectrometry and Laser-Assisted Rapid Evaporative Ionization Mass Spectrometry for Salivary Metabolomics.

Whereas urine and blood are typically targeted in clinical research, saliva represents an interesting alternative because its intrinsic metabolome is chemically diverse and reflective for various biological processes. Moreover, saliva collection is easy and noninvasive, which is especially valuable for cohorts in which sample collection is challenging, for example, infants and children. With this rationale, we established a validated ultra-high-performance liquid chromatography high-resolution mass spectrometry (UHPLC-HRMS) method for salivary metabolic profiling and fingerprinting. Hereby, 450 µL of saliva was centrifuged and passed over a 0.45-µm polyamide membrane filter, after which the extract was subjected to chromatographic analysis (HSS T3 column) and Q-Exactive Orbitrap-MS. For the majority of the profiled metabolites, good linearity (R2 ≥ 0.99) and precision (coefficient of variance ≤ 15%) was achieved. The fingerprinting performance was evaluated based on the complete metabolome (11 385 components), whereby 76.8% was found compliant with the criteria for precision (coefficient of variance ≤ 30%) and 82.7% with linearity (R2 ≥ 0.99). In addition, the method was proven fit-for-purpose for a cohort of 140 adolescents (6-16 years, stratified according to weight), yielding relevant profiles (45 obesity-related metabolites) and discriminative fingerprints (Q2 of 0.784 for supervised discriminant analysis). Alternatively, laser-assisted rapid evaporative ionization mass spectrometry (LA-REIMS) was established for rapid fingerprinting of saliva, thereby using a Nd:YAG laser and Xevo G2-XS QToF-MS. With an acquisition time of 0.5 min per sample, LA-REIMS offers unique opportunities for point-of-care applications. In conclusion, this work presents a platform of UHPLC-HRMS and LA-REIMS, complementing each other to perform salivary metabolomics.

Association between CNTF Polymorphisms and Adiposity Markers in European Adolescents.

OBJECTIVE: To examine the association between polymorphisms of the ciliary neurotrophic factor gene (CNTF) and total and central adiposity markers in adolescents. STUDY DESIGN: This cross-sectional study involved 1057 European adolescents aged 12-18 years enrolled in the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study. Five polymorphisms of CNTF were genotyped, and the weight, height, waist and hip circumference, and triceps and subscapular skinfold thickness of the subjects were measured and recorded. RESULTS: The T allele of rs2509914, the C allele of rs2515363, and the G allele of rs2515362 were significantly associated (after Bonferroni correction) with higher values for several adiposity markers under different inheritance models. The CNTF CCGGA haplotype (rs2509914, rs17489568, rs2515363 rs1800169, and rs2515362) was also significantly associated with lower body mass index, waist circumference, waist/height ratio, and waist/hip ratio values compared with the TCCGG haplotype under several inheritance models. CONCLUSIONS: Three polymorphisms-rs2509914, rs2515363, and rs2515362-and the CCGGA haplotype of CNTF were significantly associated with adiposity in European adolescents. These results suggest the potential role of CTNF in the development of obesity-related phenotypes.

The Moderating Role of Emotion Regulation in the Association Between Stressors With Psychological and Biological Measures in Adolescence.

OBJECTIVE: This study explored the role of emotion regulation (ER) as a moderator in the stressor-adjustment outcome relationship while identifying the relevant stressors. METHODS: In 214 adolescents (10-18 years; 51.4% boys), stressors (parent and peer relations, negative events), psychological outcomes (adolescent perceived stress, psychopathology symptoms, negative affect), and biological measures related to the stress response (hair cortisol [HC], heart rate variability [HRV]) as well as ER strategies-maladaptive (MalER), adaptive (AdER), and their ratio (Mal/AdER)-were measured and analyzed via linear regression, adjusted for age, sex, and socioeconomic status. RESULTS: Parental rejection and bullying were the stressors with the strongest association with psychological outcomes (ß range = |0.217-0.352|, p < .05). In addition, parental rejection was associated with HC (ß = 0.242, p = .035), whereas none of the stressors were associated with HRV. MalER was linked to all, and AdER to most psychological outcomes (ß range = |0.21-0.49|, p < .05). MalER, but not AdER, was associated with HC (ß = 0.25, p = .009), whereas none of the ER strategy types were associated with HRV. Moreover, several associations between stressors and psychological outcomes were moderated by MalER and Mal/AdER, whereas AdER's role as a moderator was not confirmed. CONCLUSIONS: The study confirmed that adolescents' stressors are associated with both psychological and physiological outcomes and moderated by MalER or Mal/AdER. The lack of moderation by AdER directs toward the maladaptive shift theory. Investigations through a longitudinal, rather than a cross-sectional design, could further elucidate the current observations. Moreover, training in how to use ER effectively has a potential of increasing adolescents' stress resilience.

Cross-Sectional and Longitudinal Associations Between Psychosocial Well-Being and Cardiometabolic Markers in European Children and Adolescents.

OBJECTIVE: Research examining aspects of positive mental health as potential predictors of cardiometabolic health in young populations is scarce. We investigated the associations between psychosocial well-being and waist circumference (WAIST), blood pressure (BP), the homeostasis model assessment for insulin resistance, triglycerides, and high-density lipoprotein cholesterol considering life-style factors as mediators. METHODS: Data of European children and adolescents participating in the baseline (2007/2008), first follow-up (FU1; 2009/2010) and second follow-up (FU2; 2013/2014) examinations of the IDEFICS/I.Family study were used (ncross-sectional = 6519; nlongitudinal = 1393). A psychosocial well-being score was calculated from 16 items on emotional well-being, self-esteem, and social relationships (0-48 points). Cardiometabolic markers were transformed to age- and sex-specific and, in case of BP, also height-specific z scores. Life-style factors included diet, physical activity, sleep, and electronic media use. Applying path analysis, we obtained unstandardized estimates of direct and indirect effects of well-being on cardiometabolic markers. RESULTS: Cross-sectionally, well-being score showed a negative direct and a negative indirect effect through life-style factors on WAIST z score (estimate per 4-point increase, -0.051 [p = .001] and -0.014 [p < .001], respectively). Longitudinally, positive changes in well-being score between baseline and FU1 and between FU1 and FU2, respectively, demonstrated negative indirect effects through life-style factorsFU2 on WAIST z scoreFU2. Both cross-sectionally and longitudinally, higher levels of well-being showed lowering indirect effects on homeostasis model assessment, BP, and triglyceride z scores and an increasing indirect effect on high-density lipoprotein cholesterol z score through both life-style factors and WAIST z score. CONCLUSIONS: These results supported our hypothesis that a healthier life-style may be one mechanism through which higher well-being is linked with lower abdominal obesity and fewer other cardiometabolic disorders in young populations. TRIAL REGISTRATION: Pan-European IDEFICS/I.Family children cohort, ISRCTN registry number: ISRCTN62310987 (http://www.isrctn.com/ISRCTN62310987).