Glucose Metabolism In Children Research Articles

Reversibility of Hyperglycemic States in Children with Obesity - Diagnostic Pitfalls in the Assessment of Glucose Metabolism in Children and Adolescents with Obesity

Disorders of glucose metabolism in children with obesity are less common than in adults. There is also evidence that they may be transient. The aims of this study were to determine the prevalences of impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and type 2 diabetes mellitus (DM2) and its reversibility in pediatric patients with obesity and to define the factors determining the reversibility of prediabetes or progression to diabetes. Retrospective analysis included of young patients with obesity. Patients presented and were treated between 2000-2022 at a single center. The study included 573 (316 girls; 55.15%) Caucasian patients with median body mass index (BMI) Z-score of 3.95 (range 2.0-9.9) and median age 13.9 (2.9-17.1) years old. OGTT results were normal in 90.8% (n=520) and signs of prediabetes occurred in 9.2% (n=53); IFG 17%, IGT 88.7%, DM 0%. Among those who underwent OGTT twice (n=53), impaired glucose regulation was present in 9.3% (n=5) (IFG 40%, IGT 80%, DM 0%) at baseline and in 14.8% subject (n=8) (IFG 25%, IGT 50%, DM 25%) at follow-up after lifestyle modification only. After 12-36 months of follow up, in those with a history of IGT, 60% reverted to normal glucose tolerance, while IFG and IGT persisted in 20% and 20%, respectively, and none progressed to DM. The risk factors for progression of glucose metabolism disorders were increase of BMI Z-score, higher insulin levels and elevated homeostatic model assessment-insulin resistance. IFG and IGT are common in pediatric patients with obesity, while the progression to DM2 is rare. Disorders of glucose metabolism have reversible character.

High prevalence of impaired glucose metabolism among children and adolescents living with HIV in Ghana.

Antiretroviral therapy (ART)-associated metabolic abnormalities, including impairment of glucose metabolism, are prevalent in adults living with HIV. However, the prevalence and pathogenesis of impaired glucose metabolism in children and adolescents living with HIV, particularly in sub-Saharan Africa, are not well characterized. We investigated the prevalence of impaired glucose metabolism among children and adolescents living with perinatally infected HIV in Ghana. In this multicentre, cross-sectional study, we recruited participants from 10 paediatric antiretroviral treatment clinics from January to June 2022 in 10 facilities in Greater Accra and Eastern regions of Ghana. We determined impaired glucose metabolism in the study sample by assessing fasting blood sugar (FBS), insulin resistance as defined by the homeostatic model assessment for insulin resistance (HOMA-IR) index and glycated haemoglobin (HbA1c) levels. The prevalence of impaired glucose metabolism using each criterion was stratified by age and sex. The phenotypic correlates of glucose metabolism markers were also assessed among age, sex, body mass index (BMI) and waist-to-hip ratio (WHR). We analysed data from 393 children and adolescents living with HIV aged 6-18 years. A little over half (205/393 or 52.25%) of the children were female. The mean age of the participants was 11.60 years (SD = 3.50), with 122/393 (31.00%) aged 6-9 years, 207/393 (52.67%) aged 10-15 years, and 62/393 (15.78%) aged 16-18 years. The prevalence rates of glucose impairment in the study population were 15.52% [95% confidence interval (CI): 12.26-19.45], 22.39% (95% CI: 18.54-26.78), and 26.21% (95% CI: 22.10-30.78) using HbA1c, HOMA-IR, and FBS criteria, respectively. Impaired glucose metabolism detected by FBS and HOMA-IR was higher in the older age group, whereas the prevalence of abnormal HbA1c levels was highest among the youngest age group. Age and BMI were positively associated with FBS and HOMA-IR (p < 0.001). However, there was negative correlation of WHR with HOMA-IR (p < 0.01) and HbA1c (p = 0.01). The high prevalence of impaired glucose metabolism observed among the children and adolescents living with HIV in sub-Saharan Africa is of concern as this could contribute to the development of metabolic syndrome in adulthood.

Studies in children with obesity in two European treatment centres show a high prevalence of impaired glucose metabolism in the Swedish cohort.

To investigate the prevalence and possible risk factors for the development of impaired glucose metabolism in children and adolescents with obesity. This was a cross-sectional retrospective cohort study, including 634 patients with obesity and 98 normal weight controls aged 4-18 years from the Beta-cell function in Juvenile Diabetes and Obesity (Beta-JUDO) cohort, a dual-centre study at Uppsala University Hospital (Sweden) and Paracelsus Medical University Hospital (Salzburg, Austria) conducted between 2012 and 2021. A longitudinal subgroup analysis, including 188 of these subjects was performed. Impaired glucose metabolism was diagnosed by oral glucose tolerance tests according to American Diabetes Association criteria. The prevalence of impaired glucose metabolism was 72% in Uppsala patients, 24% in Salzburg patients, 30% in Uppsala controls and 13% in Salzburg controls. The prevalence was lower at the follow-up visits compared with baseline both in Uppsala and Salzburg patients. A family history of type 2 diabetes showed the strongest association with impaired glucose metabolism at the follow-up visits besides belonging to the Uppsala cohort. The prevalence of impaired glucose metabolism was extraordinarily high in Swedish children and adolescents with obesity, but decreased during the follow-up period.

Postprandial glucose metabolism in children and adolescents with type 1 diabetes mellitus: potential targets for improvement.

The main goal of therapeutic management of type 1 Diabetes Mellitus (T1DM) is to maintain optimal glycemic control to prevent acute and long-term diabetes complications and to enable a good quality of life. Postprandial glycemia makes a substantial contribution to overall glycemic control and variability in diabetes and, despite technological advancements in insulin treatments, optimal postprandial glycemia is difficult to achieve. Several factors influence postprandial blood glucose levels in children and adolescents with T1DM, including nutritional habits and adjustment of insulin doses according to meal composition. Additionally, hormone secretion, enteroendocrine axis dysfunction, altered gastrointestinal digestion and absorption, and physical activity play important roles. Meal-time routines, intake of appropriate ratios of macronutrients, and correct adjustment of the insulin dose for the meal composition have positive impacts on postprandial glycemic variability and long-term cardiometabolic health of the individual with T1DM. Further knowledge in the field is necessary for management of all these factors to be part of routine pediatric diabetes education and clinical practice. Thus, the aim of this report is to review the main factors that influence postprandial blood glucose levels and metabolism, focusing on macronutrients and other nutritional and lifestyle factors, to suggest potential targets for improving postprandial glycemia in the management of children and adolescents with T1DM.

722 Lung function and impaired glucose metabolism in children with cystic fibrosis

722 Lung function and impaired glucose metabolism in children with cystic fibrosis

536 Effect of elexacaftor-tezacaftor-ivacaftor on nutritional status and glucose metabolism in children and adolescents with cystic fibrosis

536 Effect of elexacaftor-tezacaftor-ivacaftor on nutritional status and glucose metabolism in children and adolescents with cystic fibrosis

The bad rainbow of COVID-19 time: effects on glucose metabolism in children and adolescents with obesity and overweight

The bad rainbow of COVID-19 time: effects on glucose metabolism in children and adolescents with obesity and overweight

Vitamin D Deficiency in Obese Children Is Associated with Some Metabolic Syndrome Components, but Not with Metabolic Syndrome Itself.

Vitamin D deficiency in children is a common nutritional issue in many populations worldwide, associated not only with skeletal malformations but, as recent studies suggest, also with the development of obesity and metabolic syndrome. The aim of this observational study was to assess the nutritional status of vitamin D in a group of Polish children with obesity and different grades of metabolic syndrome, with a consequent analysis of the correlation between vitamin D levels and the components of metabolic syndrome. For that purpose, the group of 78 participants (mean age: 14.18 ± 2.67 years) was recruited and further grouped in relation to vitamin D status into two groups of children with and without vitamin D deficiency. The biochemical parameters associated with obesity as well as anthropometric measures were assessed and analysed in search of significant differences between the groups. In the current group of children with obesity and vitamin D deficiency, HDL (45.00 ± 9.29) and adiponectin (7.21 ± 1.64) were found to be significantly lower than in their peers without vitamin D deficiency, whereas W/HtR (0.60 ± 0.04) and TG (171.31 ± 80.75) levels proved to be significantly higher. Body composition analysis using bioelectrical impedance returned no significant findings. The above findings suggest that vitamin D deficiency may influence lipid and glucose metabolism in children, leading to the development of abnormalities characteristic of the metabolic syndrome. A W/HtR parameter was shown to be a sensitive marker of abdominal obesity, which might provide an important means of assessing the correlation between vitamin D and this type of obesity. Independently, vitamin D deficiency may also influence the endocrinological function of adipose tissue, leading to lower concentrations of adiponectin. These in turn presented a linear correlation with the high results of the OGTT in the second hour of the test, hinting at its potential role in the pathophysiology of insulin resistance.

Association of gut microbiota and glucose metabolism in children with disparate degrees of adiposity.

To investigate the characteristics of gut microbiota in children with disparate degrees of adiposity, and analyze the association between gut microbiota, glucose metabolism indicators, and inflammatory factors. Clinical data were examined in 89 Chinese children. Children with a body fat percentage ≥ 30% were diagnosed as obese, and ≥ 35% in males and ≥ 40% in females were further defined as severe obesity. The composition of gut microbiota was determined by 16S rDNA-based metagenomics. The study population (9.75 ± 1.92-year-old) was characterized as normal weight (n=29), mild obesity (n=27) and severe obesity (n=33) groups. Linear discriminant analysis Effect Size (LEfSe) analysis found that compared to the severe obesity group, subjects with mild obesity had more prevalent members of the phylum Fusobacteria, the genus Alistipes, and fewer members of genus Granulicatella and Clostridium (p < 0.05). For subjects with mild obesity, Spearman's correlation analysis revealed that fasting plasma glucose positively correlated with species A.indistinctus, A.putredinis, and negatively correlated with species Ruminococcus gnavus; LBP negatively correlated with species Clostridium hathewayi, and Blautia producta. For subjects with severe obesity, oral glucose tolerance test 2h plasma glucose (OGTT2HPG) negatively correlated with the phylum Synergistetes, genus Pyramidobacter, species Veillonella parvula, P.piscolens, and positively correlated with species B.producta, INS and HOMA-IR negatively correlated with the genus Haemophilus, species H. parainfluenzae, lipopolysaccharide-binding protein (LBP) negatively correlated with the phylum Actinobacteria, genus Bifidobacterium, Lactobacillus, and species B.longum (all p < 0.05). Phylogenetic investigation of communities by reconstruction of unobserved states 2 (PICRUSt2) analysis discerned that the glucose metabolism pathway, gluconeogenesis I was curtailed in the severe obesity group. The gut microbiota could favourably compensate for glucose metabolism in children with obesity. Genus Haemophilus and Bifidobacterium longum may influence glucose tolerance and insulin resistance in children with severe obesity.

Early glucose metabolism in children at risk for type 1 diabetes based on islet autoantibodies compared to low-risk control groups.

BackgroundAnatomic variation or early differences in glucose metabolism have been linked to the development of type 1 diabetes. We aimed to describe early glucose metabolism based on HbA1c, oral glucose tolerance test (OGTT), and random plasma glucose years before the presentation of type 1 diabetes in five risk groups based on autoantibody combinations. For the first time, we were able to include for comparison children with very low risk of progression to type 1 diabetes.MethodsThe Finnish Diabetes Prediction and Prevention birth cohort study screened newborn infants for HLA susceptibility to type 1 diabetes since 1994. Those carrying a risk genotype were prospectively followed up with islet autoantibody testing. Glucose parameters were obtained starting from the time of seroconversion. By 31 August 2014, 1162 children had developed at least one islet autoantibody and were included in the current study. Type 1 diabetes was diagnosed in 335 children (progressors). In the non-progressor groups, 207 developed multiple (≥2) biochemical islet autoantibodies, 229 a single biochemical autoantibody, 370 ICA only, and 64 transient autoantibodies. Children were divided into five risk groups. Glucose metabolism was evaluated.ResultsWe observed lower HbA1c values in early follow-up 4.5 to 6.0 years before diagnosis in the progressors when compared to the same time in children with a single biochemical autoantibody or low-risk (ICA only and transient) participants, who did not progress to clinical type 1 diabetes. However, no such differences were observed in OGTTs or random plasma glucose. The variation was minimal in glucose values in the low-risk groups.ConclusionWe report the possibility of early alteration in glucose metabolism in future progressors. This could suggest early defects in multiple glucose-regulating hormones.

The bad rainbow of COVID-19 time: effects on glucose metabolism in children and adolescents with obesity and overweight.

BackgroundCOVID-19 restriction measurements have enhanced the obesity status in the pediatric population which might further contribute to obesity-related glucose-insulin metabolism alterations. Therefore, we retrospectively compared anthropometric and OGTT data on children with obesity during the 13 years before and during the COVID-19 pandemic.Subjects/methodsData from 741 children with obesity and overweight were retrieved and clustered into seven groups starting from year 2008–2009 until 2020–2021. Differences in anthropometric measurements and glucose/insulin metabolism were evaluated between the different groups.ResultsChildren with overweight and obesity in the COVID-19 restriction group did not present increased values of SDS­Body Mass Index (BMI). Significantly higher values for Waist Circumference (WC), SDS-WC, Waist/Height ratio (WHtR), and body mass fat were detected in these children (all P < 0.01). Fasting glycaemia, glucose, and insulin excursions were significantly higher compared to pre­ pandemic children (all P < 0.01). Insulin resistance was higher while insulin secretion was lower (all P < 0.01) determining a significantly higher percentage of impaired glucose tolerance in the COVID-19 restriction group (P < 0.002). Furthermore, High-Density Lipoprotein (HDL) cholesterol was significantly lower (P < 0.01) and SDS for systolic and diastolic blood pressure values were significantly higher (P = 0.03 and P = 0.02, respectively).ConclusionsCOVID-19 restriction measurements determined profound alterations in glucose and insulin metabolism in children with obesity and overweight. Urgent strategies are needed in order to reverse COVID-19 restriction measures’ effects on glucose and insulin metabolism.

The Relationship between Fat Mass Percentage and Glucose Metabolism in Children and Adolescents: A Systematic Review and Meta-Analysis.

To assess the relationship between fat mass percentage (FMP) and glucose metabolism in children aged 0–18 years we performed a systematic review of the literature on Medline/PubMed, SinoMed, Embase and Cochrane Library using the PRISMA 2020 guidelines up to 12 October 2021 for observational studies that assessed the relationship of FMP and glucose metabolism. Twenty studies with 18,576 individuals were included in the meta-analysis. The results showed that FMP was significantly associated with fasting plasma glucose (FPG) (r = 0.08, 95% confidence interval (CI): 0.04–0.13, p < 0.001), fasting plasma insulin (INS) (r = 0.48, 95% CI: 0.37–0.57, p < 0.001), and homeostasis model assessment (HOMA)- insulin resistance (IR) (r = 0.44, 95% CI: 0.33–0.53, p < 0.001). The subgroup analysis according to country or overweight and obesity indicated that these associations remained significant between FMP and INS or HOMA-IR. Our results demonstrated that there is a positive relationship between FMP and FPG. Moreover, subgroup analysis according to country or overweight and obesity indicated that FMP is significantly associated with INS and HOMA-IR. This is the first known systematic review and meta-analysis to determine the associations of FMP with glucose metabolism in children and adolescents.

Serum Asprosin Concentrations in Children with Prader-Willi Syndrome: Correlations with Metabolic Parameters.

Children with Prader–Willi syndrome (PWS) are characterized by severe obesity. Asprosin is a newly discovered protein hormone produced by the white adipose tissue and is correlated with insulin resistance. The aim of our study was to describe the concentrations of serum asprosin in children with PWS compared to those with overweight/obesity and normal weight, and to explore the postprandial change in asprosin concentrations in participants with PWS and BMI-z matched controls. We enrolled 52 children, 23 with PWS, 8 with overweight/obesity, and 21 with normal weight. Fasting levels of asprosin, glucose, and insulin were collected in all children, and postprandial asprosin and fasting levels of acyl ghrelin (AG) and leptin were also determined in a subsample of participants. There were no significant differences among groups in fasting levels of asprosin, glucose, insulin, and HOMA-IR. Fasting serum asprosin and 1-h post-meal serum asprosin did not differ in children with PWS nor in BMI-z matched controls. Fasting asprosin showed an adjusted positive correlation with glucose in children with obesity (r = 0.93, p = 0.007) but not in children with PWS nor children with normal weight. Circulating asprosin might be a predictor of early alterations in glucose metabolism in children with obesity. More research is needed to further explain the association between asprosin, food intake, metabolism, and obesity in PWS.

The Impact of Growth Hormone Therapy on Glucose Metabolism of Children with Growth Hormone Deficiency

Introduction: Growth hormone (GH) has well known effects on carbohydrate metabolism. The aim of our study is to evaluate the effects of GH therapy on glucose metabolism in children with GH deficiency. Materials and methods: Fasting glycemia was measured before and after 12, 24 and 36 months of GH therapy (0.035 mg/kg/day). Besides, the data of Glycated heamoglobin perfomed after a treatment duration of 2 years were collected. Results: The fasting glycemias remained normals with only one patient with impairment fasting glycose. The mean of fasting glycemia after 12, 24 and 36 months was slightly higher than the pre-treatment values. As for the glycated heamoglobin, it was normal for all our patients except three ones. Conclusion: Our data show that GH therapy in GH deficient children have an increasement impact of the levels of fasting glycemia and glycated heamoglobin, but further studies with large cohort and longuer follow-up ares required to evaluate this impact.

Irizin: a new myokine and its effect on metabolism

Muscles release hormones (myokines) into the bloodstream, which affect the production of cytokines and their metabolism in various organs and tissues. One of them is irisin, a new adipokine with important autocrine and endocrine functions. It is produced not only by muscle tissue, but also by lymphoid organs, adipose and nervous tissue. It has been proven that this myokine can play a role in the pathogenesis of metabolic and oncological diseases, inflammation, aging and neurogenesis. The content of irisin in the blood is regulated not only by physical activity, but also by diet, changes in body weight, and drugs. The increased interest in studying the relationship of irisin with metabolic diseases is due to the search for a potentially new point of application for overcoming type 2 diabetes mellitus and insulin resistance. Irisin plays a major role in the interaction of the muscle­adiposetissue­bone­brain axis. It has been found that exercise has a positive effect on the functioning of the nervous system. Irisin has an anabolic effect on the skeleton and plays a significant role in bone metabolism. It has been established that exercise is a protective factor in people with cancer, reduces the toxicity of chemotherapy and improves the quality of life of patients, although the mechanisms of this phenomenon require further study. The relationship between circulating irisin levels and impaired glucose metabolism in children is discussed. It is proposed to use irisin as one of the predictors of childhood obesity. Its protective role in pregnancy and in newborns is being studied. A decrease in serum irisin levels is considered a marker of gestational diabetes. It has been suggested that cord blood irisin levels may be a reliable predictor of obesity in the future. Further research is needed to better understand the mechanism of action of this myokine in various diseases in children and to identify the relationship between circulating irisin levels and the amount of brownadipose tissue in newborns of different gestational age and with different birth weights.

Relationship between glucose homeostasis and obesity in early life-a study of Italian children and adolescents.

Epidemic obesity is the most important risk factor for prediabetes and type 2 diabetes (T2D) in youth as it is in adults. Obesity shares pathophysiological mechanisms with T2D and is likely to share part of the genetic background. We aimed to test if weighted genetic risk scores (GRSs) for T2D, fasting glucose (FG) and fasting insulin (FI) predict glycaemic traits and if there is a causal relationship between obesity and impaired glucose metabolism in children and adolescents. Genotyping of 42 SNPs established by genome-wide association studies for T2D, FG and FI was performed in 1660 Italian youths aged between 2 and 19 years. We defined GRS for T2D, FG and FI and tested their effects on glycaemic traits, including FG, FI, indices of insulin resistance/beta cell function and body mass index (BMI). We evaluated causal relationships between obesity and FG/FI using one-sample Mendelian randomization analyses in both directions. GRS-FG was associated with FG (beta = 0.075 mmol/l, SE = 0.011, P = 1.58 × 10−11) and beta cell function (beta = −0.041, SE = 0.0090 P = 5.13 × 10−6). GRS-T2D also demonstrated an association with beta cell function (beta = −0.020, SE = 0.021 P = 0.030). We detected a causal effect of increased BMI on levels of FI in Italian youths (beta = 0.31 ln (pmol/l), 95%CI [0.078, 0.54], P = 0.0085), while there was no effect of FG/FI levels on BMI. Our results demonstrate that the glycaemic and T2D risk genetic variants contribute to higher FG and FI levels and decreased beta cell function in children and adolescents. The causal effects of adiposity on increased insulin resistance are detectable from childhood age.

Consumption of sugar‐sweetened beverages and metabolic markers in children – a narrative review of the evidence

AbstractA healthy hydration habit is an important aspect of a healthy diet, but recommendations on beverage choices are still less detailed than food‐based recommendations. It is our working hypothesis that frequent consumption of sugar‐sweetened beverages (SSBs) may cause insulin resistance by inducing rapid increases in insulin concentration. Insulin resistance is central to the risk of developing type 2 diabetes and may also be linked to development of obesity. This narrative review aims to review the literature on SSB consumption in relation to adverse markers of glucose metabolism in children. Literature searches were conducted in Medline and Embase via Ovid® on June 21st and June 22nd, 2020. From 8892 titles, abstracts were screened from 76 publications. This screening resulted in the inclusion of 13 publications, while reference screening of the 13 publications resulted in inclusion of an additional six publications. A total of 11 cross‐sectional studies, two prospective studies, five experimental studies and one randomised controlled trial were reviewed. The majority of the reviewed studies reported significant, positive associations between SSB consumption and a broad range of adverse markers of glucose metabolism. Results suggested that the adverse effects of SSB consumption on metabolic health may not be limited to individuals with overweight. The results suggest that more frequent consumption of SSBs may be associated with adverse markers of glucose metabolic health among children. However, the evidence is limited by a paucity of prospective studies and randomised controlled trials, as well as by profound heterogeneity in definitions of exposures and outcomes.

Hyperglycemia and Adverse Pregnancy Outcome Follow-Up Study: newborn anthropometrics and childhood glucose metabolism.

We aimed to examine associations of newborn anthropometric measures with childhood glucose metabolism with the hypothesis that greater newborn birthweight, adiposity and cord C-peptide are associated with higher childhood glucose levels and lower insulin sensitivity. Data from the international, multi-ethnic, population-based Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study and the HAPO Follow-Up Study were used. The analytic cohort included 4155 children (mean age [SD], 11.4 [1.2] years; 51.0% male). Multiple linear regression was used to examine associations of primary predictors, birthweight, newborn sum of skinfolds (SSF) and cord C-peptide, from HAPO with continuous child glucose outcomes from the HAPO Follow-Up Study. In an initial model that included family history of diabetes and maternal BMI during pregnancy, birthweight and SSF demonstrated a significant, inverse association with 30min and 1h plasma glucose levels. In the primary model, which included further adjustment for maternal sum of glucose z scores from an oral glucose tolerance test during pregnancy, the associations were strengthened, and birthweight and SSF were inversely associated with fasting, 30min, 1h and 2h plasma glucose levels. Birthweight and SSF were also associated with higher insulin sensitivity (Matsuda index) (β = 1.388; 95% CI 0.870, 1.906; p < 0.001; β = 0.792; 95% CI 0.340, 1.244; p < 0.001, for birthweight and SSF higher by 1 SD, respectively) in the primary model, while SSF, but not birthweight, was positively associated with the disposition index, a measure of beta cell compensation for insulin resistance (β = 0.034; 95% CI 0.012, 0.056; p = 0.002). Cord C-peptide levels were inversely associated with Matsuda index (β = -0.746; 95% CI -1.188, -0.304; p < 0.001 for cord C-peptide higher by 1 SD) in the primary model. This study demonstrates that higher birthweight and SSF are associated with greater childhood insulin sensitivity and lower glucose levels following a glucose load, associations that were further strengthened after adjustment for maternal glucose levels during pregnancy. Graphical abstract.

Inadequate sleep as a contributor to impaired glucose tolerance: A cross-sectional study in children, adolescents, and young adults with circadian rhythm sleep-wake disorder.

Sleep deprivation and circadian disruption are associated with decreased insulin sensitivity and hyperglycemia. It is uncertain whether circadian sleep-wake disorder (CRSWD), which relates to both the homeostatic sleep system and the circadian timing system, affects glycemic regulation and insulin secretion. We aimed to examine the associations among sleep duration, sleep architecture or circadian rhythm of the sleep-wake cycle, and glucose metabolism in children, adolescents, and young adults with CRSWD. This cross-sectional observational study of 124 patients with CRSWD took place at Hyogo Children's Sleep and Development Medical Research Center in Hyogo, Japan. The patients underwent a 3-hour oral glucose tolerance test, anthropometric measurements, sleep-log analyses, and polysomnography. Analysis of covariance models were used to assess the association between sleep architecture or circadian rhythm of sleep-wake cycle and glucose/insulin homeostasis, adjusted for confounding variables such as age, gender, standardized body mass index, and sleep apnea index. Impaired glucose tolerance was detected in 25.8% of all patients with CRSWD. After adjustment for confounding variables, we found a negative association between total sleep time (TST) and the 2-hour plasma glucose level. Stage N1 (%TST) was also a significant predictor of 3-hour glucose level. However, we did not detect an association between circadian rhythm of the sleep-wake cycle and glucose/insulin measures. Decreased sleep duration and increased stage N1 (%TST) were associated with hyperglycemia in patients with CRSWD. Further research should elucidate how circadian misalignment in patients with CRSWD is associated with glucose and insulin homeostasis.

Season, Terrestrial Ultraviolet Radiation, and Markers of Glucose Metabolism in Children Living in Perth, Western Australia.

Seasonality in glucose metabolism has been observed in adult populations; however, little is known of the associations between season and glucose metabolism in children. In this study, we examined whether markers of glucose metabolism (fasting glucose, insulin and HbA1c) varied by season in a paediatric population (6–13 years of age) located in Perth (Western Australia, n = 262) with data categorised by weight. Linear regression was used to analyse the nature of the relationships between mean daily levels of terrestrial ultraviolet radiation (UVR) (prior to the day of the blood test) and measures of glucose metabolism. Fasting blood glucose was significantly lower in autumn compared to spring, for children in combined, normal and obese weight categories. Fasting insulin was significantly lower in autumn and summer compared to winter for individuals of normal weight. HbA1c was significantly higher in summer (compared with winter and spring) in overweight children, which was in the opposite direction to other published findings in adults. In children with obesity, a strong inverse relationship (r = −0.67, p = 0.002) was observed for fasting glucose, and daily terrestrial UVR levels measured in the previous 6 months. Increased safe sun exposure in winter therefore represents a plausible means of reducing fasting blood sugar in children with obesity. However, further studies, using larger paediatric cohorts are required to confirm these relationships.