Nonpharmacological interventions on glycated haemoglobin in youth with type 1 diabetes: a Bayesian network meta-analysis.

The available evidence on the impact of specific non-pharmacological interventions on glycaemic control is currently limited. Consequently, there is a need to determine which interventions could provide the most significant benefits for the metabolic health of young individuals with type 1 diabetes mellitus. The aim of this study was to identify optimal nonpharmacological interventions on glycaemic control, measured by glycated haemoglobin (HbA1c), in children and adolescents with type 1 diabetes. Systematic searches were conducted in PubMed, Web of Science, Scopus, and SPORTDiscus from inception to July 1, 2023. Randomised clinical trials (RCT) investigating nonpharmacological interventions (e.g., physical activity, nutrition, and behavioural therapies) were included. Primary outcome was change in HbA1c levels. Secondary outcome was change in daily insulin dose requirement. Seventy-four RCT with 6,815 participants (49.43% girls) involving 20 interventions were analysed using a network meta-analysis. Most interventions showed greater efficacy than standard care. However, multicomponent exercise, which includes aerobic and strength training (n = 214, standardised mean difference [SMD] =- 0.63, 95% credible interval [95% CrI] - 1.09 to - 0.16) and nutritional supplements (n = 146, SMD =- 0.49, - 0 .92 to - 0.07) demonstrated the greatest HbA1c reductions. These interventions also led to the larger decreases in daily insulin needs (n = 119, SMD =- 0.79, 95% CrI -  1.19 to - 0.34) and (n = 57, SMD =- 0.62, 95% CrI -  1.18 to - 0.12, respectively). The current study underscores non-pharmacological options such as multicomponent exercise and nutritional supplements, showcasing their potential to significantly improve HbA1c in youth with type 1 diabetes. Although additional research to confirm their efficacy is required, these approaches could be considered as potential adjuvant therapeutic options in the management of type 1 diabetes among children and adolescents.

Incidence of type 1 diabetes mellitus in children and adolescents under 20 years of age across 55 countries from 2000 to 2022: A systematic review with meta-analysis.

AIMS: The aim of this study was to determine the global incidence of type 1 diabetes mellitus (T1DM) in children and adolescents under 20 years of age from 2000 to 2022. MATERIALS AND METHODS: Two reviewers searched three electronic databases (PubMed, Web of Science, and CINAHL) for studies published between January 2000 and November 2022. Pooled estimates of T1DM incidence with a 95% confidence interval (CI) per 100,000 person-years were calculated by country/region, sex, age, and COVID-19 pandemic period (pre-COVID-19 and pandemic). RESULTS: The study included 126 studies from 55 countries and 18 regions. The incidence rate (IR) of T1DM from 2000 to 2022 was 14.07 (95%CI, 12.15-16.29) per 100,000 person-years. Finland and high-income North America had the highest IR, with 56.81 (95%CI, 55.91-57.73) and 28.77 (95%CI, 26.59-31.13) per 100,000 person-years, respectively. The IR was 13.37 (95%CI, 10.60-16.88) per 100,000 person-years in boys and 13.87 (95%CI, 11.51-16.70) per 100,000 person-years in girls. There were statistically significant differences among different age ranges: 0-4 versus 5-9 and 10-14 years old (p < 0.001); 5-9 versus 15-19 (p < 0.001) and 10-14 versus 15-19 years old (p = 0.003). Finally, during the pandemic period (2020-2022), the IR was 24.84 (95%CI, 17.16-35.96) per 100,000 person-years, which was higher but not significant compared with the prepandemic period (2017-2019) of 13.56 (95%CI, 7.49-24.56) per 100,000 person-years (p = 0.090). CONCLUSIONS: The IR of T1DM in children and adolescents under 20 years of age is substantial, especially during the pandemic period, although it varies across regions. More reliable data from additional countries are needed to determine the worldwide incidence of T1DM.

Reference values and associated factors of controlled attenuation parameter and liver stiffness in adults: A cross-sectional study.

BACKGROUND & AIMS: The utilization of non-invasive techniques for liver fibrosis and steatosis assessment has gained acceptance as a viable substitute for liver biopsy in clinical practice. This study aimed to establish normative data for the controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) by age and gender, as well as to explore the relationship between anthropometric measures, clinical status, and biochemical profile according to the 90th percentile cut-off values for CAP/LSM in a U.S. adult population. METHODS AND RESULTS: In this cross-sectional analysis, 7.522 US adults aged 20-80 years from the National Health and Nutrition Examination Survey (NHANES 2017-2020) were included. CAP and LSM were quantified using the FibroScan® 502-v2 device. A comprehensive range of data was collected, including sociodemographic, anthropometric, biochemical, lifestyle, and clinical conditions. Participants were segmented by sex and age. The median ± standard deviation (SD) for CAP was significantly lower in women (258.27 ± 61.02 dB/m) than in men (273.43 ± 63.56 dB/m), as was the median ± SD for LSM (women: 5.50 ± 4.12 kPa, men: 6.36 ± 5.63 kPa). Although median CAP and LSM values displayed an upward trend with age, statistical significance was not achieved. Notably, higher liver CAP values (above the 90th percentile) correlated with more pronounced clinical and biochemical profile differences compared to lower CAP values (below the 90th percentile) (p < 0.001). CONCLUSIONS: Our study provides age- and sex-stratified standard values for CAP and LSM in a sizeable, nationally representative cohort of adults. The evidence of sex-specific variations in TE test results from our study sets the stage for future research to further corroborate these findings.

Combined aerobic and muscle-strengthening activity guidelines and their association with obesity in US adolescents.

Most of the evidence on physical activity for maintaining a healthy weight in adolescents is based solely on aerobic physical activity alone, with little attention given to the muscle strength component. This study aimed to investigate the associations between aerobic activities and muscle-strengthening activities (MSA) and overweight/obesity among a representative sample of adolescents. Data from the United States-based Youth Risk Behavior Surveillance System for the 2011-2019 cycle were used in this cross-sectional study. Adolescents self-reported their adherence to aerobic and MSA guidelines, as well as their height and weight. Overweight and obesity were defined using the age- and sex-specific criteria of the Centers for Disease Control and Prevention, with a body mass index (BMI) ≥85th and ≥95th percentiles, respectively. We examined the associations between adherence to physical activity guidelines (reference: not meeting either of the physical activity guidelines) and overweight/obesity or obesity using binary logistic regressions. These analyses were adjusted for race/ethnicity, sex, age, screen time, sleep duration, tobacco, alcohol, fruit, vegetables, and soda consumption. A total of 42 829 adolescents (48.98% girls) were included in the study. Of these, 22.23% met both guidelines for physical activity, 30.47% had overweight/obesity, and 14.51% had obesity. Compared with meeting neither guideline, meeting both aerobic and MSA guidelines was associated with lower odds of having overweight/obesity (odds ratio [OR] = 0.64, 95% confidence interval [CI], 0.60 to 0.68) and obesity (OR = 0.52, 95% CI 0.48 to 0.56). These results were consistent across years of assessment, sex, and race/ethnicity. In conclusion, our results highlight the importance of MSA, which is often overlooked in physical activity recommendations in many studies, in combating childhood obesity in the United States.

Acute effect of physical activity on academic outcomes in school-aged youth: A systematic review and multivariate meta-analysis.

BACKGROUND: There has been an increase in the number of studies examining the effect of acute and chronic physical activity on academic outcomes in children and adolescents in the last two decades. We aimed to systematically determine the acute effects of physical activity on academic outcomes in school-aged youth and to examine possible moderators. METHODS: We conducted a systematic search using PubMed, Web of Science, SPORTDiscus, and PsycINFO databases (from inception to 11th January 2023) for studies assessing the acute effects of physical activity on academic performance-related outcomes in school-aged youth. A univariate and multivariate meta-analysis was conducted based on a random-effects model with restricted maximum likelihood used to pool the academic outcomes results (Hedge's g). RESULTS: We included 11 articles (803 children and adolescents [range: 6-16 years]) in the systematic review. Overall, acute physical activity increased academic outcomes (Hedge's g = 0.35, 95% CI: 0.20-0.50). Multivariate meta-analyses revealed that physical activity increased academic performance in mathematics (Hedge's g = 0.29, 95% CI: 0.16-0.42) and language (Hedge's g = 0.28, 95% CI: 0.09-0.47). Only behavior change techniques (Hedge's g = 0.54, 95% CI, 0.18-0.90, p < 0.001) played a significant role in this relationship. CONCLUSIONS: A single bout of physical activity can improve academic outcomes in school-aged youth, which may serve as a complementary tool for the educational field. However, the observed heterogeneity in the results indicates that we should interpret the findings obtained with caution.

Meeting muscle-strengthening recommendation is associated with lower adiposity, higher physical fitness and healthier lifestyle in adolescents: The EHDLA study.

AIM: To determine the prevalence of adolescents who meet muscle-strengthening activities (MSA) recommendation and their associations with anthropometric variables, physical fitness, and lifestyle behaviours in a sample of Spanish adolescents aged 12-17 years. METHODS: This was a cross-sectional study using data from The Eating Healthy and Daily Life Activities (EHDLA) Study. Participants reported the days on which they engaged in MSA (≥3 days per week were considered to meet World Health Organization recommendation). Physical fitness was assessed with the ALPHA fitness battery. Additionally, body mass index, waist circumference, skinfolds and body fat percentage were assessed. Lifestyle variables were recreational screen time, sleep time and adherence to the Mediterranean diet. The associations between MSA and outcome variables were tested with linear and logistic regressions. RESULTS: Of the 852 participants, 48% met MSA recommendation. Meeting MSA recommendation was associated with lower adiposity and higher performance in the shuttle run test, maximal oxygen consumption, standing long jump, speed-agility, flexibility, lower screen time (in weekdays) and higher adherence to the Mediterranean diet. CONCLUSION: Engaging in MSA once or twice a week was linked with more desirable health outcomes than not engaging in such activities. However, meet with MSA recommendation (i.e., at least 3 days per week) reinforced these benefits.

Twenty-four-hour movement guidelines during adolescence and its association with obesity at adulthood: results from a nationally representative study.

To determine the association between adherence to the 24-h movement guidelines during adolescence with obesity at adulthood 14 years later in a nationally representative cohort. We analyzed data from 6984 individuals who participated in Waves I (1994-1995) and IV (2008-2009) of the National Longitudinal Study of Adolescent Health (Add Health) in the USA. Obesity was defined by the International Obesity Task Force cut-off points at Wave I and adult cut-points at Wave IV (body mass index [BMI]≥30 kg/m2 and waist circumference [WC]≥102 cm in male and 88 cm in female). Physical activity, screen time and sleep duration were self-reported. Adolescents who met screen time recommendation alone (ß = -1.62 cm, 95%CI -2.68 cm to -0.56), jointly with physical activity (ß = -2.25 cm, 95%CI -3.75 cm to -0.75 cm), and those who met all three recommendations (ß = -1.92 cm, 95%CI -3.81 cm to -0.02 cm) obtained lower WC at Wave IV than those who did not meet any of these recommendations. Our results also show that meeting with screen time recommendations (IRR [incidence rate ratio] = 0.84, 95%CI 0.76 to 0.92) separately and jointly with physical activity recommendations (IRR = 0.86, 95%CI 0.67 to 0.97) during adolescence is associated with lower risk of abdominal obesity at adulthood. In addition, adolescents who met all 24-h movement recommendations had lower risk of abdominal obesity later in life (IRR = 0.76, 95%CI 0.60 to 0.97). CONCLUSION: Promoting the adherence to the 24-h movement guidelines from adolescence, especially physical activity and screen time, seems to be related with lower risk of abdominal obesity later in life, but not for BMI. WHAT IS KNOWN: • Some studies have shown a relationship between adherence to 24-h movement guidelines and adiposity or obesity markers in youth. However, most of these studies have a cross-sectional design or a short follow-up. WHAT IS NEW: • This is the first study which determined the association between adherence to the 24-h movement guidelines during adolescence with obesity at adulthood 14 years later in a nationally representative US cohort. • Meeting the 24-h movement guidelines from adolescence seems to be related with lower risk of abdominal obesity later in life, but not for body mass index.

Contribution of active commuting to and from school to device-measured physical activity levels in young people: A systematic review and meta-analysis.

OBJECTIVE: To analyze the contribution of active commuting to and from school (ACS) to device-measured light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) levels in young people aged 6 to 18 years old, as well as, in both trip directions (i.e., home-school, school-home). METHODS: This systematic review was conducted according to the PRISMA statement, and five different databases were used for the systematic search (PubMed, Web of Science, SPORTdiscuss, Cochrane Library, and National Transportation Library) using PECO strategy. RESULTS: A total of 14 studies met all the eligibility criteria, which compile 7127 participants. The overall ACS weighted LPA was 19.55 min (95% CI: 3.84-35.26; I2 = 99.9%, p < 0.001) and 68.74 min (95% CI: 6.09-131.39; z = 2.15, p = 0.030) during the home-school and school-home trips, respectively. For MVPA, the overall ACS weighted MVPA was 8.98 min (95% CI: 5.33-12.62; I2 = 99.95%, p < 0.001) during the home-school trip and 20.07 min (95% CI: 13.62-26.53; I2 = 99.62%, p < 0.001) during the school-home trip. CONCLUSION: ACS may contribute about 48% of the PA recommendations in young people on school days if both trip directions are actively performed. Therefore, future studies aimed at increasing daily PA levels in young population should focus on promoting students' ACS. PROSPERO registration number: CRD42020162004A.

Is fear of hypoglycemia a major barrier to an active lifestyle in children and adolescents with type 1 diabetes? The Diactive-1 Study.

Studies on fear of hypoglycemia as a barrier to physical activity among youth with type 1 diabetes (T1D) have been limited and controversial, most of which used self-reported assessment. The aim of the study was to evaluate the relationship between fear of hypoglycemia and physical activity and glycemic metrics in children and adolescents with T1D. Seventy-four participants (6-18 years of age; 44.6% females) with T1D were included in the study. Physical activity was assessed through accelerometry on nine consecutive days, and blood glucose metrics were simultaneously tracked using continuous glucose monitoring (time-in-range and hypoglycemic events). A closed question was used to evaluate the avoidance of physical activity due to fear of hypoglycemia. Fifteen participants (20%) reported avoiding physical activity due to fear of hypoglycemia. The group reporting no fear of hypoglycemia showed lower total physical activity (-35.33 min/day, 95% confidence interval [CI] (-77.57 to -1.47)) and light physical activity (-29.81 min/day, 95% CI -64.01 to -2.75) and higher sedentary time (77.95 min/day, 95% CI 26.46-136.87) per day compared with those with fear of hypoglycemia. No difference was found between those patients with fear of hypoglycemia in terms of meeting the recommendations of glycated hemoglobin, glucose coefficient of variation, and time-in-range when compared to those with no fear of hypoglycemia. In conclusion, children and adolescents with fear of hypoglycemia were more active, less sedentary, and had similar glycemic metrics to those without fear. Our results therefore suggest that fear of hypoglycemia may be less of a barrier to an active lifestyle than previously believed.

What is the role of adherence to 24-hour movement guidelines in relation to physical fitness components among adolescents?

BACKGROUND: Physical inactivity, excessive sedentary time, and lack of sleep time have been independently associated with lower health-related physical fitness. However, little is known about the combined association between 24-h movement guidelines (i.e., physical activity, recreational screen time, and sleep duration) and components of physical fitness. OBJECTIVE: The main aim was to examine the likelihood of having high/very high levels on different components of physical fitness based on meeting with 24-h movement guidelines. METHODS: In this cross-sectional study, 1276 Spanish youths (13.07 ± 0.86; 55.88% boys), aged 11-16 years, completed self-reported questionnaires on physical activity, recreational screen time, and sleep duration. Physical fitness components were assessed by 20-m shuttle-run test, standing long jump test, handgrip strength test, and 4 × 10-m shuttle-run test. Meeting 24-h movement guidelines was defined as: 9-11 h/day (children aged 5-13) or 8-10 h/day (adolescents aged 14-17) of sleep, ≤2 h/day of recreational screen time and at least 60 min/day of moderate-to-vigorous physical activity. The probability of having a high/very high score for each physical fitness components (i.e., ≥60th centile according to the normative cut-off points for European adolescents) in relation to adherence to 24-h movement guidelines was analyzed using a series of binary logistic regressions. RESULTS: Participants who met the three 24-h movement guidelines were more likely to have high/very high for cardiorespiratory fitness (OR = 3.31; 95% CI: 1.79, 6.14; p < 0.001), standing long jump (OR = 1.91; 95% CI: 1.06, 3.45; p = 0.031), muscular fitness (OR = 2.05; 95% CI: 1.09, 3.86; p = 0.048) and physical fitness (OR = 1.99; 95% CI: 1.08, 3.66; p = 0.012), but not for handgrip strength (OR = 1.15; 95% CI: 0.64, 2.01; p = 0.636) and speed/agility (OR = 1.65; 95% CI: 0.92, 2.96; p = 0.093), compared to those who did not meet all three recommendations. CONCLUSION: Since meeting the three 24-h movement guidelines increased the likelihood of having higher levels in most physical fitness components, it seems necessary to promote these movement behaviors early in life, as they could serve as a gateway for improving health-related fitness in future generations.

Prevalence of meeting all three 24-h movement guidelines and its correlates among preschool-aged children.

The aim of the present study was twofold: first, to determine the meeting all three 24-h movement guidelines in Colombian preschool-aged children, and second, to explore the associations between different socio-ecological correlates and the meeting of these guidelines. This was a cross-sectional study with data from the Encuesta Nacional de Situación Nutricional (ENSIN-2015) in Colombia, 2015-2016. The sample comprised 3002 low-income preschoolers (3-4 years old, 50.7% boys). Data on physical activity, screen time, and sleep time were collected using the Cuestionario para la Medición de Actividad Física y Comportamiento Sedentario, reported by their parents. In total, 18 potential correlates (individual, interpersonal, organizational, and community level) were analyzed. Backward binary logistic regression analysis was performed with the potential correlates as independent variables and meeting all three 24-h movement guidelines as dependent variables. The prevalence of preschoolers meeting all three 24-h movement guidelines or none was 4.8% and 16.6%, respectively. In the final model, boys (odds ratio [OR] = 1.87, 95% confidence interval [CI] 1.00-3.50) and those who do not have television in their bedroom (OR = 2.09, 95%CI 1.05-4.14) were more likely to meet all three 24-h movement guidelines compared to with girls and those who have television, respectively. In conclusion, strategies to promote adherence to all 24-h movement guidelines among low-income preschoolers are warranted, and should focus on actions considering the importance of sex and home environment changes to support these movement behaviors.

Adherence to aerobic and muscle-strengthening activities guidelines: a systematic review and meta-analysis of 3.3 million participants across 32 countries.

OBJECTIVE: To estimate the global prevalence of meeting the WHO guidelines for both aerobic and muscle-strengthening activities (MSA) in populations aged ≥5 years, and whenever possible to explore this prevalence according to sociodemographic and lifestyle factors. DESIGN: A systematic review and meta-analysis. DATA SOURCES: Five databases were systematically searched for studies published from inception to September 2022. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Articles with representative samples aged ≥5 years reporting the prevalence of meeting both aerobic and MSA guidelines were included. RESULTS: Twenty-one studies comprising 3 390 001 individuals from 32 countries were included. Overall adherence to the aerobic and MSA guidelines was 17.12% (95% CI 15.42% to 18.88%) in adults ≥18 years (n=3 346 723). Among adolescents aged 12-17 years, adherence to both guidelines was 19.74% (95% CI 14.72% to 25.31%) (n=43 278). No studies reported data for children aged 5-11 years. Women, older age, low/medium education levels, underweight or obesity, and poor and moderate self-rated health were associated with lower adherence to the physical activity guidelines (p<0.001) among adults, although the prevalence remained very low in all cases. Subgroup analyses were not conducted with children and adolescents due to a lack of studies. CONCLUSIONS: Only one out of five adolescents and adults met the recommended combined aerobic and MSA guidelines. Large-scale public health interventions promoting both types of exercise are needed to reduce the associated burden of non-communicable diseases. PROSPERO REGISTRATION NUMBER: CRD42022338422.

Cross-cultural adaptation, reliability, and validation of the Spanish perceived physical literacy instrument for adolescents (S-PPLI).

Objective: The aim of this study was to examine the reliability and validity of the Spanish Perceived Physical Literacy Instrument (S-PPLI) questionnaire in Spanish adolescents. Method: The participants of this study were 360 Spanish adolescents (aged 12-17 years) from three secondary schools in the Region of Murcia (Spain). A cultural adaptation process of the original version of the PPLI questionnaire was developed. Confirmatory factor analysis was applied to test the three-factor structure of physical literacy. Intraclass correlation coefficients were computed to estimate the test-retest concordance. Results: Using a confirmatory factor analysis, the factor loading of all items above the standard of 0.40 ranged from 0.53 to 0.77, suggesting that the observed variables sufficiently represented the latent variables. Analyses for convergent validity showed average variance extracted values that ranged from 0.40 to 0.52 and composite reliability values higher than 0.60. All the correlations were below the recommended cutoff point of 0.85, which indicated that the three physical literacy factors achieved adequate discriminant validity. Intraclass correlation coefficients ranged from 0.62 to 0.79 (p < 0.001 for all items), which indicated moderate/good reliability. Conclusions: Our results suggest that the S-PPLI is a valid and reliable measure of physical literacy among Spanish adolescents.

Associations between physical fitness components with muscle ultrasound parameters in prepuberal children.

BACKGROUND/OBJECTIVES: Muscle ultrasound is a convenient technique to visualize normal and pathological muscle tissue as it is non-invasive and real-time. This technique is related to several physical performance parameters and body composition components in adults; however, this relationship remains unexplored in early aged. We aimed to evaluate the association between physical fitness components with muscle ultrasound parameters in prepuberal children. METHODS: A sample of 282 prepuberal children aged 5-9 years (144 boys) participated in the study. A trained sonographer obtained six B-mode images from femoral rectus for muscle thickness, subcutaneous adipose tissue (SAT) and area of the muscle of interest, were captured, and muscle ultrasound parameters (echo-intensity: EI uncorrected, EI correct equations) and intramuscular adipose tissue (IMAT) were extracted. Lean muscle tissue has low EI, whereas intramuscular fat and connective tissue have high EI. Physical fitness components (cardiorespiratory fitness, upper and lower muscle strength, speed-agility, and overall fitness levels) were also evaluated. Children were categorized as fit or unfit for each specific fitness test. RESULTS: After adjustment for sex and age, higher physical fitness components and overall fitness (z-score) levels were negatively associated with EI, IMAT, and SAT (cardiorespiratory fitness ß range = -0.264 to -0.298; upper-muscular strength ß range = -0.389 to -0.457; and lower-muscular strength ß range = -0.202 to -0.279; and speed-agility ß range = -0.257 to -0.302). Children categorized as fit according to four physical fitness components had lower EI uncorrected, EI correct equation 1-2, IMAT, and SAT than unfit children for each respective tests (all Ps < 0.001). CONCLUSION: Physical fitness components are inversely associated with EI, IMAT, SAT after adjusting for potential confounders, including sex and age, in prepuberal children. The present study strengthens the idea that muscle and adiposity parameters is affected by physical fitness even from early childhood.

Discriminatory capacity of obesity indicators as predictors of high liver fat in US adolescents.

BACKGROUND: The aims of this study were to assess the potential of 16 anthropometric, body composition and endocrine indexes as predictors of high liver fat and determine the most appropriate cut-off points in US adolescents. METHODS: A cross-sectional study was conducted on a population of 816 adolescents aged 12-17 years. The FibroScan® 502V2 device was used to estimate the controlled attenuation parameter (CAP). Body fat percentage, fat mass, trunk fat percentage and trunk fat mass were measured by dual-energy X-ray absorptiometry. Anthropometric data and metabolic parameters were determined. Receiver operating characteristic curves were analysed to estimate the optimal cut-off points that best identify adolescents with high liver fat (CAP ≥90th percentile). RESULTS: In boys, triponderal mass index (TMI) had the highest area under curve (AUC) value (0.865) and the optimal cut-off score for TMI was 17.47 kg/m3 , which had 81.32 sensitivity and 82.99 specificity. In girls, trunk fat index (TFI) had the highest AUC value (0.826) and its optimal cut-off score in screening for high liver fat was 3.76 kg/m2 , which had 74.04 sensitivity and 88.03 specificity. Fat mass index (FMI) index had the second highest AUC values (0.863 in boys 0.812 in girls) in both sex; the cut-off point for the detection of high liver fat was <8.66 kg/m2 for girls and <7.45 kg/m2 for boys. CONCLUSION: Assessment of TMI in boys, TFI in girls, and FMI in both sexes are low-cost and easy-to-use parameters that may be useful as early screening tools for possible high liver fat in adolescents.

Defining values for controlled attenuation parameter and liver stiffness in youth without liver disease.

BACKGROUND: We aimed to determine the reference values to define an age-specific normal range of controlled attenuation parameter (CAP, a measure of liver steatosis) and liver stiffness measurement (LSM) values assessed by ultrasound-based transient elastography in adolescents without underlying liver disease. METHODS: A total of 462 participants were included in this cross-sectional study using data from NHANES 2017-2018. LSM and CAP were carried out using the FibroScan® M-probe. Anthropometric, metabolic and hematological parameters were measured. RESULTS: The median CAP was 199.0 dB/m (150.0-245.0 dB/m, 10th to 90th percentiles) and the median LSM was 4.7 kPa (3.4-6.3 kPa, 10th to 90th percentiles) for ages 12-19.9 years. Regression analyses show that the CAP and LSM were not positively correlated with age (boys CAP R2 = 0.001, p = 0.576 and LSM R2 = 0.012, p = 0.096; girls CAP R2 = 0.011, p = 0.113 and LSM R2 = 0.006, p = 0.236). Finally, CAP was positively associated with LSM in girls (ß = 0.189, p = 0.005) but not in boys (ß = -0.083, p = 0.202). CONCLUSIONS: The reference values indicated here for LSM and CAP will help in the screening of adolescents between ages 12 and 19.9 years and might serve as a useful method for identifying those youth at high risk of nonalcoholic fatty liver disease. IMPACT: The reference values indicated in this study for liver stiffness measurement (LSM) and controlled attenuation parameter (CAP) will help in the screening of adolescents between ages 12 and 19.9 years in clinical practice. The cutoffs of LSM and CAP might serve as a useful method for identifying those youth at high risk of nonalcoholic fatty liver disease.

Low handgrip strength is associated with higher liver enzyme concentrations in US adolescents.

BACKGROUND: Increasing evidence highlights the role of muscular strength as a protective factor for cardiometabolic health in adolescents. However, it is not known the relationship between liver enzyme concentrations, liver disease risk factors, and muscular strength among young populations. The aim of this study was to determine the association between muscle strength and liver enzymes and chronic liver disease risk among US adolescents. METHODS: Data from the NHANES cross-sectional study (2011-2014) was used. A total of 1270 adolescents were included in the final analysis (12-17 years old). Absolute handgrip strength (kg) was normalized according to body composition parameters by body weight [NHSw], whole-body fat [NHSf], and trunk fat [NHSt]). RESULTS: In boys, handgrip strength was inversely associated with higher values of aspartate aminotransferase (AST) and gamma glutamyl transpeptidase (GGT) for all estimations of muscle strength (NHSw, NHSf, and NHSt) (p < 0.050). Likewise, boys with high and intermediate NHSw, NHSf, and NHSt presented lower AST and GGT than their counterparts with low handgrip strength (p < 0.050). CONCLUSIONS: Our findings highlight the importance of muscular strength during adolescence since they could help in developing better liver enzyme profiles among adolescent population. IMPACT: Our research suggests that US adolescents with low handgrip strength have higher values of liver enzymes as well as a higher prevalence of chronic liver disease. These findings are clinically meaningful and highlight the importance of muscular strength during adolescence since they could help in developing better liver enzyme profiles among young populations.

Trajectories of 24-h movement guidelines from middle adolescence to adulthood on depression and suicidal ideation: a 22-year follow-up study.

BACKGROUND: The 24-h movement guidelines for youth and adults recommend the specific duration of physical activity, sedentary time, and sleep duration to ensure optimal health, but little is known about its relationship to mental health indicators. The aim of the study was to explore the association between 24-h movement guidelines in adolescence and its trajectories from middle adolescence (12-17 years old) to adulthood (33-39 years old) with depression and suicidal ideation in adulthood. METHODS: This prospective cohort study included individuals who participated in Waves I (1994-1995) and V (2016-2018) of the National Longitudinal Study of Adolescent Health (Add Health) in the United States. Physical activity, screen time and sleep duration were measured using questionnaires. Adults were categorized as having depression if they had a self-reported history of depression and/or prescription medication-use for depression in the previous four weeks. Suicidal ideation was assessed by a self-reported single question in both waves. Poisson regression analyses were used to estimate the incidence rate ratio (IRR) of depression and suicidal ideation at adulthood, according to meeting specific and combinations of 24-h movement guidelines at Wave I and its trajectories from adolescence to adulthood. RESULTS: The study included 7,069 individuals (56.8% women). Adolescents who met physical activity guidelines and all three guidelines at middle adolescence had lower risk of depression (IRR = 0.84, 95%CI 0.72 to 0.98) and suicidal ideation (IRR = 0.74, 95%CI 0.55 to 0.99) at adulthood than those who did not meet any of these guidelines, respectively. Individuals who met the guidelines for screen time and all three guidelines in both adolescence and adulthood had lower risk of depression (screen time, IRR = 0.87, 95% CI 0.72 to 0.98; all three, IRR = 0.37, 95% CI 0.15 to 0.92) and suicidal ideation (screen time, IRR = 0.74, 95% CI 0.51 to 0.97; all three, IRR = 0.12, 95% CI 0.06 to 0.33) than those who never met the guidelines. Additionally, individuals who did not meet all three guidelines in adolescence but met the guidelines in adulthood had lower risk of suicidal ideation than those who never met the guidelines (IRR = 0.81, 95%CI 0.45 to 0.89). CONCLUSION: Our findings highlight the importance of promoting and maintaining adherence to the 24-h movement guidelines from middle adolescence to adulthood to prevent mental health problems. However, our findings must be interpreted carefully due to declared limitations, e.g., the self-reported assessments which are subject to sources of error and bias or that the dataset used to gauge meeting a guidelines (1994-1996) was made later (2016).

Is adherence to the Mediterranean diet associated with healthy habits and physical fitness? A systematic review and meta-analysis including 565 421 youths.

The relationship between adherence to the Mediterranean diet (MD), physical activity (PA), sedentary behaviour and physical fitness levels has been analysed in several studies; however, there is mixed evidence among youth. Thus, this study aimed to meta-analyse the associations between adherence to the MD, PA, sedentary behaviour and physical fitness among children and adolescents. Three databases were systematically searched, including cross-sectional and prospective designs with a sample of healthy youth aged 3-18 years. Random effects inverse-variance model with the Hartung-Knapp-Sidik-Jonkman adjustment was used to estimate the pooled effect size (correlation coefficient (r)). Thirty-nine studies were included in the meta-analysis, yielding a total of 565 421 youth (mean age, 12·4 years). Overall, the MD had a weak-to-moderate positive relationship with PA (r 0·14; 95 % CI 0·11, 0·17), cardiorespiratory fitness (r 0·22; 95 % CI 0·13, 0·31) and muscular fitness (r 0·11; 95 % CI 0·03, 0·18), and a small-to-moderate negative relationship with sedentary behaviour (r -0·15; 95 % CI -0·20, -0·10) and speed-agility (r -0·06; 95 % CI -0·12, -0·01). There was a high level of heterogeneity in all of the models (I2 ≥ 75 %). Overall, results did not remain significant after controlling for sex and age (children or adolescents) except for PA. Improving dietary habits towards those of the MD could be associated with higher physical fitness and PA in youth, lower sedentary behaviours and better health in general.

Association between air pollution and 24-h movement behaviours in a representative sample of Spanish youth.

PURPOSE: The aim of this study was to analyse the relationship between air pollution and 24-h movement guidelines in Spanish children/adolescents. METHODS: This cross-sectional study analysed secondary data from the Encuesta Nacional de Salud Española (2017), a representative survey for the Spanish population. The original dataset included 6016 Spanish young people (aged 0-14 years). Since the data on 24-h movement recommendations were limited to Spanish young people aged 2-14 years, the final sample included 4398 (49.2% girls) Spanish young people. Air pollution was evaluated by particulate matter 2.5 (PM2.5) from different Spanish regions and divided into tertiles representing areas with low, medium, and high pollution. Sleep duration and recreational screen time and were reported by the parents/caregivers. Physical activity was evaluated by an adapted version of the International Physical Activity Questionnaire. Time spent in screen time, sleep, and physical activity were classified as meeting or not the 24-h movement guidelines. RESULTS: After adjusting for several covariates (sex, age, immigrant status, region, socioeconomic status, and body mass index), lower odds of meeting with the 24-h movement recommendations were found in those living in areas with medium (odds ratio [OR] = 0.55; confident interval [CI] 95%, 0.46-0.67) or high air pollution (OR = 0.45; CI 95%, 0.36-0.55), compared with those living in areas with low air pollution. CONCLUSIONS: The movement behaviour of young people seems to be associated with the presence of air pollution among Spanish youth. Spanish public health agencies could consider the development of strategies to mitigate the health risks for children/adolescents in high air polluted areas.