Prevalences of diabetes and impaired glucose regulation in a Danish population: the Inter99 study

Early menopause in mothers and the risks of pre-diabetes and type 2 diabetes mellitus in female and male offspring: a population-based cohort study

BACKGROUND

Genetic factors and an unfavorable intrauterine environment may contribute to the development of metabolic disorders in offspring later in life. The present study aims to investigate and compare the risks of pre-diabetes mellitus (pre-DM), type 2 diabetes mellitus (T2DM) and abnormal glucose tolerance in female and male offspring with early maternal menopausal age versus those with normal maternal menopausal age, later in life.

METHODS

In this prospective population-based study, there were 1,516 females and 1,563 males with normal maternal menopausal age, as well as 213 females and 237 males with early maternal menopausal age. Unadjusted and adjusted cox regression models were used to assess the hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between early maternal menopausal age with pre-DM, T2DM and abnormal glucose tolerance in offspring. Statistical analysis was performed using the STATA software package; the significance level was set at P < 0.05.

RESULTS

The present study revealed a higher risk of pre-DM in female offspring with early maternal menopausal age compared to females with normal maternal menopausal age (unadjusted HR (95% CI): 1.42 (0.98, 2.05); P = 0.06 (marginal significant) and adjusted HR (95% CI): 1.47 (1.00, 2.16); P = 0.04). Additionally, a higher risk of abnormal glucose tolerance among female offspring with early maternal menopausal age in adjusted model was observed (HR (95% CI): 1.13 (0.99-1.29); P = 0.06, marginal significant). However, no significant differences were observed in the risks of developing pre-DM and abnormal glucose tolerance in male offspring with early maternal menopausal age compared to males with normal maternal menopausal age in both unadjusted and adjusted models. No significant difference was observed in the risk of T2DM in the offspring with early maternal menopausal age compared to offspring with normal maternal menopausal age.

CONCLUSIONS

This pioneering study, characterized by a long-term follow-up, demonstrated that early maternal menopausal age is associated with an increased risk of developing pre-DM in female offspring later in life. It may be advisable to implement screening for pre-DM and glucose metabolism disorders in these female offspring.

CLINICAL TRIAL NUMBER

Not applicable.

Rare MTNR1B variants causing diminished MT2 signalling associate with elevated HbA1c levels but not with type 2 diabetes

AIMS/HYPOTHESIS

An intronic variant (rs10830963) in MTNR1B (encoding the melatonin receptor type 2 [MT2]) has been shown to strongly associate with impaired glucose regulation and elevated type 2 diabetes prevalence. However, MTNR1B missense variants have shown conflicting results on type 2 diabetes. Thus, we aimed to gain further insights into the impact of MTNR1B coding variants on type 2 diabetes prevalence and related phenotypes.

METHODS

We conducted a cross-sectional study, performing MTNR1B variant burden testing of glycaemic phenotypes (N=248,454, without diabetes), other cardiometabolic phenotypes (N=330,453) and type 2 diabetes prevalence (case-control study; N=263,739) in the UK Biobank. Similar burden testing with glycaemic phenotypes was performed in Danish Inter99 participants without diabetes (N=5711), and type 2 diabetes prevalence (DD2 cohort serving as cases [N=2930] and Inter99 serving as controls [N=4243]). Finally, we evaluated the effects of MTNR1B variants on the melatonin-induced glucose regulation response in a recall-by-genotype study of individuals without diabetes.

RESULTS

In the UK Biobank, MTNR1B variants were not associated with cardiometabolic phenotypes, including type 2 diabetes prevalence, except that carriers of missense MTNR1B variants causing impaired MT2 signalling exhibited higher HbA1c levels compared with non-carriers (effect size, β, 0.087 SD [95% CI 0.039, 0.135]). Similarly, no significant associations were observed with phenotypes associated with glycaemic phenotypes in the Inter99 population. However, carriers of variants impairing MT2 signalling demonstrated a nominally significant lower glucose-stimulated insulin response (β -0.47 SD [95% CI -0.82, -0.11]). A reduced insulin response was also observed in carriers of variants impairing MT2 signalling (β -476.0 [95% CI -928.6, -24.4]) or the rs10830963 variant (β -390.8 [95% CI -740.1, -41.6]) compared with non-carriers after melatonin treatment.

CONCLUSIONS/INTERPRETATION

The higher type 2 diabetes prevalence previously observed in carriers of missense MTNR1B variants causing impairment in MT2 signalling was not replicated in the UK Biobank, yet carriers had elevated HbA1c levels.

DATA AVAILABILITY

Data (Inter99 cohort and recall-by-genotype study) are available on reasonable request from the corresponding author. Requests for DD2 data are through the application form at https://dd2.dk/forskning/ansoeg-om-data . Access to UK Biobank data can be requested through the UK Biobank website ( https://www.ukbiobank.ac.uk/enable-your-research ).

Short bouts of hypoxia improve insulin sensitivity in adults with type 2 diabetes

Hypoxia stimulates glucose uptake independently from the action of insulin. The purpose of this study was to determine the effect of intermittent hypoxia, consisting of alternating short bouts of breathing hypoxic and room air, on glucose concentration, insulin concentration, and insulin sensitivity during an oral glucose tolerance test in adults with type 2 diabetes and adults with normal glycemic control. Nine adults with type 2 diabetes (2 women, HbA1c: 7.3 ± 1.5%, age: 52 ± 13 yr) and nine adults with normal glycemic control (4 women, HbA1c: 5.4 ± 0.1%, age: 24 ± 4 yr) performed a 2-h oral glucose tolerance test on two separate visits to the laboratory. Following ingestion of the glucose drink, participants were exposed to either an intermittent hypoxia protocol, consisting of eight 4-min hypoxic cycles at a targeted oxygen saturation of 80% interspersed with breathing room air to resaturation, or a sham protocol consisting of eight 4-min normoxic cycles interspersed with breathing room air. Intermittent hypoxia did not attenuate the increase in glucose concentration but attenuated the increase in insulin concentration in response to an oral glucose tolerance test in comparison with the sham protocol in adults with type 2 diabetes. Insulin sensitivity was greater during intermittent hypoxia in comparison with the sham protocol in adults with type 2 diabetes (0.043 ± 0.036 vs. 0.032 ± 0.046 μmol/kg/min/pmol, P = 0.01), but did not change in the control group (0.122 ± 0.015 vs. 0.128 ± 0.008 μmol/kg/min/pmol, P = 0.12). In conclusion, intermittent hypoxia improved insulin sensitivity in adults with type 2 diabetes.NEW & NOTEWORTHY The aim of this study was to determine the effect of short bouts of hypoxia, which stimulates glucose uptake, on glucose concentration, insulin concentration, and insulin sensitivity during an oral glucose tolerance test in adults with type 2 diabetes and adults with normal glycemic control. Intermittent hypoxia acutely improved insulin sensitivity in adults with type 2 diabetes.

Glycemic status and effect on mortality: Multifactorial prevention programme for cardiovascular disease in Finnish primary care

AIMS

To compare 13-year mortality rates in normoglycemic, prediabetic and diabetic subjects attending a community-based screening and intervention programme.

METHODS

Population survey identified 2569 cardiovascular disease (CVD) white risk subjects aged 45-70 years and without manifested CVD or diabetes. Oral glucose tolerance test was performed, and multifactorial intervention was provided. Effect of glycemic status on mortality was estimated in models adjusted for age, gender, education years, smoking, body mass index, mean arterial pressure, total cholesterol, and physical activity.

RESULTS

Of the subjects, 2055 (77 %) were normoglycemic, 380 (14 %) had prediabetes and 224 (9 %) diabetes. Compared to the normoglycemic group, the fully adjusted hazard ratios (HR) for all-cause mortality were 1.34 (95 % CI: 0.98-1.83) in the prediabetes group and 2.31 (95 % CI: 1.62-3.31) in the diabetes group. Standardized mortality rates were 0.63 (95 % CI: 0.54-0.73), 0.91 (95 % CI: 0.69-1.18), and 1.55 (95 % CI: 1.19-2.02) in the normoglycemic, prediabetes, and diabetes groups, respectively. The most common cause of death was cancer (42 % of all deaths), followed by CVD (28 %).

CONCLUSIONS/INTERPRETATION

Screen-detected diabetes carries a substantial risk of death even after primary care intervention. The pattern of excess mortality has shifted towards cancer deaths.

Myotonic dystrophy type 1 in South Korea: a comprehensive analysis of cancer and comorbidity risks

BACKGROUND AND PURPOSE

Myotonic dystrophy type 1 (DM1) is an inherited neuromuscular disorder characterized by myotonia and progressive muscle weakness. Beyond the primary symptoms, there is growing concern regarding a higher incidence of certain comorbidities in DM1 patients, including cancer, diabetes, thyroid dysfunction, and cataracts. This study was designed to examine the occurrence of these conditions among patients diagnosed with DM1 in South Korea, using data from the National Health Insurance Service database.

METHODS

The study undertook a comprehensive review of 3,842 patients diagnosed with DM1 between 2012 and 2018. We assessed the incidence of cancer and the prevalence of diabetes, thyroid dysfunction, and cataracts among these patients, comparing their rates to those in the general population.

RESULTS

In the study cohort, 463 out of 3,842 DM1 patients (12.04%) were diagnosed with cancer, indicating a substantial elevation in cancer risk with an overall standard incidence ratio of 1.9 (95% CI = 1.6-2.3, p < 0.01) when compared to the expected rates in the general population. Moreover, the prevalence of diabetes (15.2%) and thyroid dysfunction (17.6%) was noteworthy in the DM1 population. The mean age at which DM1 patients underwent cataract surgery was 55.07 years, noticeably younger than the mean age of 69.25 years for cataract surgery in the general population.

CONCLUSIONS

DM1 patients have a noteworthy occurrence of several comorbidities such as cancer, diabetes, thyroid dysfunction, and earlier cataract surgery. This highlights the importance of a comprehensive and integrative approach to the management and treatment of DM1, going beyond addressing only the primary neuromuscular symptoms. More research is required to understand the underlying mechanisms contributing to these comorbidities in DM1 patients, which may inform preventative measures and guide improvements in patient care.

Association of high-sensitivity troponin T with left ventricular dysfunction in prediabetes

BACKGROUND

Impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) are an increasingly serious problem worldwide. Tissue Doppler imaging (TDI), a non-invasive technique, may evaluate both systolic and diastolic function during the first phases of cardiovascular disease (CVD). High-sensitivity cardiac troponin T (hs-cTnT) can detect subclinical myocardial injury in asymptomatic prediabetic patients.

AIM

We aimed to investigate the relationship between left ventricular (LV) function and hs-cTnT in prediabetic patients.

METHODS

Between 1 October 2021 and 1 October 2022, we recruited 96 prediabetic and an equal number of age- and gender-matched healthy volunteers prospectively. TDI was used to evaluate both systolic and diastolic functions. Hs-cTnT levels were obtained and compared between groups.

RESULTS

It was found that the values for mitral annular plane systolic excursion (MAPSE), E, the rapid filling wave, E/Em, and the peak annular velocities of systolic excursion in the ejection period (Sm) were all significantly higher in these patients compared to healthy individuals (p < .001). Hs-cTnT was an independent predictor of left ventricular diastolic dysfunction (LVDD) and left ventricular systolic dysfunction (LVSD) (odds ratio [OR] = 2.625, 95% confidence interval [CI] = 1.324-4.308, p < .001, and OR = 1.922, 95% CI = 0.454-3.206, p = .004).

CONCLUSIONS

Prediabetics had higher hs-cTnT levels than controls. We showed that LVSD and LVDD functions were negatively affected in prediabetic patients. Our results proved that hs-cTnT levels may be associated with subclinical LV dysfunction in prediabetes.

Characterization of genetic variants of GIPR reveals a contribution of β-arrestin to metabolic phenotypes

Incretin-based therapies are highly successful in combatting obesity and type 2 diabetes1. Yet both activation and inhibition of the glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) in combination with glucagon-like peptide-1 (GLP-1) receptor (GLP-1R) activation have resulted in similar clinical outcomes, as demonstrated by the GIPR-GLP-1R co-agonist tirzepatide2 and AMG-133 (ref. 3) combining GIPR antagonism with GLP-1R agonism. This underlines the importance of a better understanding of the GIP system. Here we show the necessity of β-arrestin recruitment for GIPR function, by combining in vitro pharmacological characterization of 47 GIPR variants with burden testing of clinical phenotypes and in vivo studies. Burden testing of variants with distinct ligand-binding capacity, Gs activation (cyclic adenosine monophosphate production) and β-arrestin 2 recruitment and internalization shows that unlike variants solely impaired in Gs signalling, variants impaired in both Gs and β-arrestin 2 recruitment contribute to lower adiposity-related traits. Endosomal Gs-mediated signalling of the variants shows a β-arrestin dependency and genetic ablation of β-arrestin 2 impairs cyclic adenosine monophosphate production and decreases GIP efficacy on glucose control in male mice. This study highlights a crucial impact of β-arrestins in regulating GIPR signalling and overall preservation of biological activity that may facilitate new developments in therapeutic targeting of the GIPR system.

Risk Factors that Impact Treatment with Oral Janus Kinase Inhibitors Among Adult Patients with Atopic Dermatitis: A Nationwide Registry Study

The European Medicines Agency recently limited the use of oral Janus kinase inhibitors in certain patient populations, including those with atopic dermatitis. This cross-sectional study used the Danish national registers and Danish Skin Cohort to assess the prevalence of risk factors that potentially impact choice of treatment with oral Janus kinase inhibitors in adult patients with atopic dermatitis. From the Danish national registers and Danish Skin Cohort, 18,618 and 3,573 adults with atopic dermatitis, respectively, were identified. Half of the patients (49.5%) had, at some point, been registered to have at least 1 risk factor that could impact treatment with oral Janus kinase inhibitors. Non-modifiable risk factors recorded were cancer (5.6%), major adverse cardiovascular events (2.6%), venous thromboembolism (2.0%), smoking history (15.6%), and age ≥ 65 years (12.4%). Among patients ≥ 65 years of age, the mean (standard deviation) number of risk factors were 3 (1.4), and almost half of these patients had, at some point, been registered to have 1 or more non-modifiable risk factors in addition to their age. In conclusion, risk factors that may impact treatment with oral Janus kinase inhibitors were frequent in Danish adults with atopic dermatitis, especially among older individuals. Dermatologists need support and continuously updated long-term safety data when risk-evaluating patients with atopic dermatitis prior to initiation of advanced.

Sex differences in energy metabolism: natural selection, mechanisms and consequences

Metabolic homeostasis operates differently in men and women. This sex asymmetry is the result of evolutionary adaptations that enable women to resist loss of energy stores and protein mass while remaining fertile in times of energy deficit. During starvation or prolonged exercise, women rely on oxidation of lipids, which are a more efficient energy source than carbohydrates, to preserve glucose for neuronal and placental function and spare proteins necessary for organ function. Carbohydrate reliance in men could be an evolutionary adaptation related to defence and hunting, as glucose, unlike lipids, can be used as a fuel for anaerobic high-exertion muscle activity. The larger subcutaneous adipose tissue depots in healthy women than in healthy men provide a mechanism for lipid storage. As female mitochondria have higher functional capacity and greater resistance to oxidative damage than male mitochondria, uniparental inheritance of female mitochondria may reduce the transmission of metabolic disorders. However, in women, starvation resistance and propensity to obesity have evolved in tandem, and the current prevalence of obesity is greater in women than in men. The combination of genetic sex, programming by developmental testosterone in males, and pubertal sex hormones defines sex-specific biological systems in adults that produce phenotypic sex differences in energy homeostasis, metabolic disease and drug responses.

Rare Heterozygous Loss-of-Function Variants in the Human GLP-1 Receptor Are Not Associated With Cardiometabolic Phenotypes

CONTEXT

Lost glucagon-like peptide 1 receptor (GLP-1R) function affects human physiology.

OBJECTIVE

This work aimed to identify coding nonsynonymous GLP1R variants in Danish individuals to link their in vitro phenotypes and clinical phenotypic associations.

METHODS

We sequenced GLP1R in 8642 Danish individuals with type 2 diabetes or normal glucose tolerance and examined the ability of nonsynonymous variants to bind GLP-1 and to signal in transfected cells via cyclic adenosine monophosphate (cAMP) formation and β-arrestin recruitment. We performed a cross-sectional study between the burden of loss-of-signaling (LoS) variants and cardiometabolic phenotypes in 2930 patients with type 2 diabetes and 5712 participants in a population-based cohort. Furthermore, we studied the association between cardiometabolic phenotypes and the burden of the LoS variants and 60 partly overlapping predicted loss-of-function (pLoF) GLP1R variants found in 330 566 unrelated White exome-sequenced participants in the UK Biobank cohort.

RESULTS

We identified 36 nonsynonymous variants in GLP1R, of which 10 had a statistically significant loss in GLP-1-induced cAMP signaling compared to wild-type. However, no association was observed between the LoS variants and type 2 diabetes, although LoS variant carriers had a minor increased fasting plasma glucose level. Moreover, pLoF variants from the UK Biobank also did not reveal substantial cardiometabolic associations, despite a small effect on glycated hemoglobin A1c.

CONCLUSION

Since no homozygous LoS nor pLoF variants were identified and heterozygous carriers had similar cardiometabolic phenotype as noncarriers, we conclude that GLP-1R may be of particular importance in human physiology, due to a potential evolutionary intolerance of harmful homozygous GLP1R variants.

Aging Affects Insulin Resistance, Insulin Secretion, and Glucose Effectiveness in Subjects with Normal Blood Glucose and Body Weight

AIM

Several studies have demonstrated that factors including diabetes, including insulin resistance (IR), glucose effectiveness (GE), and the first and second phase of insulin secretion (FPIS, SPIS) could easily be calculated using basic characteristics and biochemistry profiles. Aging is accompanied by deteriorations of insulin resistance (IR) and insulin secretion. However, little is known about the roles of aging in the different phases of insulin secretion (ISEC), i.e., the first and second phase of insulin secretion (FPIS, SPIS), and glucose effectiveness (GE).

METHODS

In total, 169 individuals (43 men and 126 women) recruited from the data bank of the Meei-Jaw (MJ) Health Screening Center and Cardinal Tien Hospital Data Access Center between 1999 and 2008, with a similar fasting plasma glucose (FPG: 90 mg/dL) and BMI (men: 23 kg/m², women 22 kg/m²) were enrolled. The IR, FPIS, SPIS, and GE were estimated using our previously developed equations shown below. Pearson correlation analysis was conducted to assess the correlations between age and four diabetes factors (DFs: IR, FPIS, SPIS, and GE). The equations that are used to calculate the DF in the present study were built and published by our group.

RESULTS

The age of the participants ranged from 18 to 78 years. Men had higher FPIS but lower HDL-C levels than women (2.067 ± 0.159, 1.950 ± 0.186 μU/min and 1.130 ± 0.306, 1.348 ± 0.357 mmol/dl, accordingly). The results of the Pearson correlation revealed that age was negatively related to the IR and GE in both genders (IR: r = -0.39, p < 0.001 for men, r = -0.24, p < 0.003 for women; GE: r = 0.66, p < 0.001 for men, r = 0.78, p < 0.001 for women). At the same time, the FPIS was also only found to be negatively correlated with age in females (r = -0.238, p = 0.003), but there was no difference in the SPIS and age among both genders.

CONCLUSIONS

We have found that in Chinese subjects with a normal FPG level (90 mg/dL) and body mass index (men: 23 kg/m², women: 22: kg/m²), age is negatively related to the IR and GE among both genders. Only the FPIS was found to be negatively related to age in women. The tightness of their relationships, from the highest to the lowest, are GE, FPIS, and IR. These results should be interpreted with caution because of the small sample size.

A comprehensive map of human glucokinase variant activity

BACKGROUND

Glucokinase (GCK) regulates insulin secretion to maintain appropriate blood glucose levels. Sequence variants can alter GCK activity to cause hyperinsulinemic hypoglycemia or hyperglycemia associated with GCK-maturity-onset diabetes of the young (GCK-MODY), collectively affecting up to 10 million people worldwide. Patients with GCK-MODY are frequently misdiagnosed and treated unnecessarily. Genetic testing can prevent this but is hampered by the challenge of interpreting novel missense variants.

RESULT

Here, we exploit a multiplexed yeast complementation assay to measure both hyper- and hypoactive GCK variation, capturing 97% of all possible missense and nonsense variants. Activity scores correlate with in vitro catalytic efficiency, fasting glucose levels in carriers of GCK variants and with evolutionary conservation. Hypoactive variants are concentrated at buried positions, near the active site, and at a region of known importance for GCK conformational dynamics. Some hyperactive variants shift the conformational equilibrium towards the active state through a relative destabilization of the inactive conformation.

CONCLUSION

Our comprehensive assessment of GCK variant activity promises to facilitate variant interpretation and diagnosis, expand our mechanistic understanding of hyperactive variants, and inform development of therapeutics targeting GCK.

Interaction between gut microbiota and sex hormones and their relation to sexual dimorphism in metabolic diseases

Metabolic diseases, such as obesity, metabolic syndrome (MetS) and type 2 diabetes (T2D), are now a widespread pandemic in the developed world. These pathologies show sex differences in their development and prevalence, and sex steroids, mainly estrogen and testosterone, are thought to play a prominent role in this sexual dimorphism. The influence of sex hormones on these pathologies is not only reflected in differences between men and women, but also between women themselves, depending on the hormonal changes associated with the menopause. The observed sex differences in gut microbiota composition have led to multiple studies highlighting the interaction between steroid hormones and the gut microbiota and its influence on metabolic diseases, ultimately pointing to a new therapy for these diseases based on the manipulation of the gut microbiota. This review aims to shed light on the role of sexual hormones in sex differences in the development and prevalence of metabolic diseases, focusing on obesity, MetS and T2D. We focus also the interaction between sex hormones and the gut microbiota, and in particular the role of microbiota in aspects such as gut barrier integrity, inflammatory status, and the gut-brain axis, given the relevance of these factors in the development of metabolic diseases.

Sex Differences in Glucose Homeostasis

Sexual dimorphism has been demonstrated to have an effect on various physiological functions. In this regard, researchers have investigated its impact on glucose homeostasis in both preclinical and clinical studies. Sex differences mainly arise from physiological factors such as sex hormones, body fat and muscle distribution, and sex chromosomes. The sexual dimorphism has also been studied in the context of diabetes. Reflecting the prevalence of the disease among the population, studies focusing on the sex difference in type 1 diabetes (T1D) are not common as the ones in type 2 diabetes (T2D). T1D is reported as the only major specific autoimmune disease that exhibits a male predominance. Clinical studies have demonstrated that impaired fasting glucose is more frequent in men whereas women more commonly exhibit impaired glucose tolerance. Understanding the sex difference in glucose homeostasis becomes more attractive when focusing on the findings that highlight sexual dimorphism on the efficacy or adverse effect profile of antidiabetic medications. Thus, in this chapter, we aimed to discuss the impact of sex on the glucose homeostasis both in health and in diabetes.

14-fold increased prevalence of rare glucokinase gene variant carriers in unselected Danish patients with newly diagnosed type 2 diabetes

AIMS

Rare variants in the glucokinase gene (GCK) cause Maturity-Onset Diabetes of the Young (MODY2/GCK-MODY). We investigated the prevalence of GCK variants, phenotypic characteristics, micro- and macrovascular disease at baseline and follow-up, and treatment among individuals with and without pathogenic GCK variants.

METHODS

This is a cross-sectional study in a population-based cohort of 5,433 individuals without diabetes (Inter99 cohort) and in 2,855 patients with a new clinical diagnosis of type 2 diabetes (DD2 cohort) with sequencing of GCK. Phenotypic characteristics, presence of micro- and macrovascular disease and treatment information were available for patients in the DD2 cohort at baseline and after an average follow-up of 7.4 years.

RESULTS

Twenty-two carriers of potentially deleterious GCK variants were found among patients with type 2 diabetes compared to three among 5,433 nondiabetic individuals [OR = 14.1 (95 % CI 4.2; 47.0), p = 8.9*10^-6]. Patients with type 2 diabetes carrying GCK variants had significantly lower waist circumference, hip circumference and BMI, compared to non-carriers. Three GCK variant carriers with diabetes had microvascular complications during follow-up.

CONCLUSIONS

Approximately 0.8% of Danish patients with newly diagnosed type 2 diabetes carry non-synonymous variants in GCK and resemble patients with GCK-MODY. Glucose-lowering treatment cessation should be considered in this subset of diabetes patients.

Admission Blood Glucose Level as a Predictor of Outcome in Intensive Care Patients: A Cross-Sectional Study

INTRODUCTION

In the Intensive care unit (ICU), hyperglycemia is often observed; commonly associated with pre-existing diabetes or pre-diabetes or in nondiabetic patients. This study aimed to assess the role of admission blood sugar levels with outcomes in ICU patients.

METHODS

A total of 100 patients above 18 years of age were included in the study. A detailed history regarding the patient's age, sex, and any chronic illness were taken. Heart rate, systolic blood pressure, and Glasgow coma scale (GCS) scores were recorded. Admission blood glucose level, blood urea, total leucocyte count, and serum electrolytes were measured; and the outcome was noted.

RESULTS

The number of diabetics was significantly higher (65.5%) in the random blood sugar (RBS) ≥180 group. Hyponatremia was significantly associated with hyperglycemia. Patients with hyperglycemia had serum bicarbonate <18. A significantly greater number of patients with hyperglycemia had GCS scores of <8, and required mechanical ventilation. The duration of ICU stay and non-survivors were significantly higher in the hyperglycemia group. Random blood sugar at admission as a factor to assess outcome showed a sensitivity of 68.4 and specificity of 59.3 with a cut-off value of 197.

CONCLUSION

Admission of random blood sugar was significantly associated with poor outcomes. More stringent surveillance as well as routine blood glucose checks at the time of hospital admission should be emphasized.

Sex-differences in insulin sensitivity and insulin secretion in subjects with impaired fasting glucose and impaired glucose tolerance

AIMS

To assess sex-related differences in whole-body insulin sensitivity and insulin secretion in a group of Caucasian subjects with varying degrees of glucose tolerance.

METHODS

Sex-related differences in insulin sensitivity using the hyperinsulinemic-euglycemic clamp technique and insulin secretion using validated indexes obtained during an oral glucose tolerance test were examined among 570 non-diabetic offspring individuals having only one parent with type 2 diabetes. Participants were classified as having with NGT, isolated impaired fasting glucose (IFG), isolated impaired glucose tolerance (IGT) and combined IFG/IGT.

RESULTS

Isolated IFG, isolated IGT, and combined IFG/IGT women exhibited greater relative differences in BMI, waist circumference, and insulin-stimulated glucose disposal than their male counterparts. Formal tests for glucose tolerance status × sex interaction were statistically significant for BMI (P = 0.05) waist circumference (P = 0.04), and insulin-stimulated glucose disposal (P = 0.01) suggesting a sex-specific association. By contrast, tests for glucose tolerance status × sex interaction regarding both insulinogenic and disposition indexes were not significant.

CONCLUSIONS

This study suggests that deterioration of glucose homeostasis in women is associated with a greater fat accumulation and worsening in insulin sensitivity as compared with men.

Oral glucose tolerance testing as a complement to fasting plasma glucose in screening for type 2 diabetes: population-based cross-sectional analyses of 146 000 health examinations in Västerbotten, Sweden

OBJECTIVE

To assess the effect of adding an oral glucose tolerance test (OGTT) to fasting plasma glucose (FPG) in terms of detection of type 2 diabetes (T2D) and impaired glucose tolerance (IGT).

DESIGN

Retrospective analysis of serial cross-sectional screening study.

SETTING

Population-based health examinations within primary care in Västerbotten County, Sweden.

PARTICIPANTS

Individuals aged 40- 50 and 60 years with participation from 1985 to 2017. Those with previously diagnosed diabetes and FPG≥7 mmol/L were excluded.

PRIMARY AND SECONDARY OUTCOME MEASURES

Prevalence of hyperglycaemia on the OGTT (IGT and T2D defined as 2-hour postload capillary plasma glucose of 8.9-12.1 mmol/L and ≥12.2 mmol/L, respectively). Analyses were further stratified by age, sex and risk factor burden to identify groups at high or low risk of IGT and T2D on testing. The numbers needed to screen (NNS) to prevent one case of T2D through detection and treatment of IGT was estimated, combining prevalence numbers with average progression rates and intervention effects from previous meta-analyses.

RESULTS

The prevalence of IGT ranged from 0.9% (95% CI 0.7% to 1.1%) to 29.6% (95% CI 27.4% to 31.7%), and the prevalence of T2D ranged from 0.06% (95% CI 0.02% to 0.11%) to 7.0% (95% CI 5.9% to 8.3%), depending strongly on age, sex and risk factor burden. The estimated NNS to prevent one case of T2D through detection and lifestyle treatment of IGT ranged from 1332 among 40-year-old men without risk factors, to 39 among 60-year-old women with all risk factors combined.

CONCLUSIONS

The prevalence of hyperglycaemia on OGTT is highly dependent on age, sex and risk factor burden; OGTT should be applied selectively to high-risk groups to avoid unnecessary testing in the general population.

Postprandial Glycemic Dips Are Associated With Metabolic Disorders and CVD Risk in Euglycemic Individuals

CONTEXT

Metabolic disorders and cardiovascular disease (CVD) threaten human health. Many studies have assessed the phenomenon of metabolic disorders and CVD in patients with diabetes. However, in euglycemic individuals, the relationships between glucose regulation, metabolism, and CVD remain unclear.

OBJECTIVE

This work aimed to explore the associations between postprandial glucose dips, metabolic disorders, and CVD risk.

METHODS

We analyzed data from the Thyroid disorders, Iodine status and Diabetes Epidemiological survey (TIDE study), which included 38 878 euglycemic individuals from all 31 provinces of mainland China. The prevalence of metabolic disorders and their related components and CVD risk were calculated according to postprandial glucose dips. Logistic regression models of quartiles of postprandial glucose dips were used to further explore whether the prevalence of these disorders was associated with postprandial glucose dips.

RESULTS

Odds ratios for the fourth vs the first quartile of glucose dips were 0.59 (95% CI, 0.55-0.63) (P < .001) for metabolic disorders, 0.48 (95% CI 0.44-0.53) (P < .001) for metabolic syndrome (MetS), and 0.54 (95% CI, 0.50-0.59) (P < .001) for hyperuricemia. The odds ratio of a 10-year CVD risk greater than 20% for the fourth vs the first glucose dip quartile was 0.67 (95% CI, 0.52-0.85) (P < .001). Models adjusted for body mass index yielded similar results.

CONCLUSION

Postprandial glucose dips are associated with metabolic disorders, MetS and its related component diseases, and CVD risk. Glucose dips may be a marker of underlying metabolic abnormalities.

Absence of a sexual dimorphism in postprandial glucose metabolism after administration of a balanced mixed meal in healthy young volunteers

BACKGROUND/OBJECTIVES

A different ability to regulate glucose homeostasis between men and women may contribute to their difference in diabetes prevalence and in its predisposing conditions. Data on this issue are controversial because of heterogeneous protocols and insufficient control of confounders affecting glucose metabolism like age, body composition, and physical activity level. To clarify this issue, we compared among sexes the postprandial glucose metabolism after the administration of a balanced mixed meal normalized to daily energy expenditure.

SUBJECTS/METHODS

Thirty-six healthy young volunteers (18 men and 18 women; age, 23.9 ± 2.8 years; BMI, 21.9 ± 1.7 kg/m²) were recruited for the experiment. After overnight fast, subjects consumed a mixed meal providing 40% of daily energy expenditure (60% carbohydrates, 25% lipids, 15% proteins) estimated multiplying resting energy expenditure, obtained by Harris & Benedict equation, for the corresponding physical activity level. Blood was sampled at 0, 10, 20, 30, 45, 60, 90, 120, and 180 min and serum concentrations of glucose, insulin, and C-peptide were measured.

RESULTS

Fasting serum glucose concentrations were lower in women than in men, while fasting insulin and C-peptide concentrations did not differ between sexes. Linear mixed models did not show any significant effect of sex and sex # time interaction on postprandial serum glucose, insulin, and C-peptide concentrations. The comparison of areas under the curve between the sexes revealed similar glycemic, insulinemic, and C-peptide postprandial responses between men and women.

CONCLUSIONS

Our results do not support the hypothesis of a sexual dimorphism in the regulation of carbohydrate metabolism in young when a mixed meal normalized on individual daily energy expenditure is ingested.

Definition and Classification of Diabetes and Prediabetes and Emerging Data on Phenotypes

Diabetes diagnosis has important implications for individuals. Diagnostic criteria for fasting and 2-hour plasma glucose and HbA1c are universally agreed. Intermediate hyperglycemia/prediabetes is a risk factor for diabetes and cardiovascular disease. Because risk is a continuum, determining cut-point is problematic and reflected in significant differences in recommended fasting glucose and HbA1c criteria. Many types of diabetes are recognized. Diabetes classification systems are limited by a lack of understanding of etiopathogenetic pathways leading to diminished β-cell function. The World Health Organization classification system is designed to assist clinical care decisions. Newly recognized phenotypic clusters of diabetes might inform future classification systems.

HbA1c and brain health across the entire glycaemic spectrum

AIM

To understand the relationship between HbA1c and brain health across the entire glycaemic spectrum.

MATERIALS AND METHODS

We used data from the UK Biobank cohort consisting of 500,000 individuals aged 40-69 years. HbA1c and diabetes diagnosis were used to define baseline glycaemic categories. Our outcomes included incident all-cause dementia, vascular dementia (VD), Alzheimer's dementia (AD), hippocampal volume (HV), white matter hyperintensity (WMH) volume, cognitive function and decline. The reference group was normoglycaemic individuals (HbA1c ≥35 & <42 mmol/mol). Our maximum analytical sample contained 449,973 individuals with complete data.

RESULTS

Prediabetes and known diabetes increased incident VD (HR 1.54; 95% CI = 1.04, 2.28 and HR 2.97; 95% CI = 2.26, 3.90, respectively). Known diabetes increased all-cause and AD risk (HR 1.91; 95% CI = 1.66, 2.21 and HR 1.84; 95% CI = 1.44, 2.36, respectively). Prediabetes and known diabetes elevated the risks of cognitive decline (OR 1.42; 1.48, 2.96 and OR 1.39; 1.04, 1.75, respectively). Prediabetes, undiagnosed and known diabetes conferred higher WMH volumes (3%, 22% and 7%, respectively) and lower HV (36, 80 and 82 mm3 , respectively), whereas low-normal HbA1c had 1% lower WMH volume and 12 mm3 greater HV.

CONCLUSION

Both prediabetes and known diabetes are harmful in terms of VD, cognitive decline and AD risks, as well as lower HV. Associations appeared to be somewhat driven by antihypertensive medication, which implies that certain cardiovascular drugs may ameliorate some of the excess risk. Low-normal HbA1c levels, however, are associated with more favourable brain health outcomes and warrant more in-depth investigation.

Incidence of diabetes in South Asian young adults compared to Pima Indians

INTRODUCTION

South Asians (SA) and Pima Indians have high prevalence of diabetes but differ markedly in body size. We hypothesize that young SA will have higher diabetes incidence than Pima Indians at comparable body mass index (BMI) levels.

RESEARCH DESIGN AND METHODS

We used prospective cohort data to estimate age-specific, sex, and BMI-specific diabetes incidence in SA aged 20-44 years living in India and Pakistan from the Center for Cardiometabolic Risk Reduction in South Asia Study (n=6676), and compared with Pima Indians, from Pima Indian Study (n=1852).

RESULTS

At baseline, SA were considerably less obese than Pima Indians (BMI (kg/m²): 24.4 vs 33.8; waist circumference (cm): 82.5 vs 107.0). Age-standardized diabetes incidence (cases/1000 person-years, 95% CI) was lower in SA than in Pima Indians (men: 14.2, 12.2-16.2 vs 37.3, 31.8-42.8; women: 14.8, 13.0-16.5 vs 46.1, 41.2-51.1). Risk of incident diabetes among 20-24-year-old Pima men and women was six times (relative risk (RR), 95% CI: 6.04, 3.30 to 12.0) and seven times (RR, 95% CI: 7.64, 3.73 to 18.2) higher as compared with SA men and women, respectively. In those with BMI <25 kg/m², however, the risk of diabetes was over five times in SA men than in Pima Indian men. Among those with BMI ≥30 kg/m², diabetes incidence in SA men was nearly as high as in Pima men. SA and Pima Indians had similar magnitude of association between age, sex, BMI, and insulin secretion with diabetes. The effect of family history was larger in SA, whereas that of insulin resistance was larger in Pima Indians CONCLUSIONS: In the background of relatively low insulin resistance, higher diabetes incidence in SA is driven by poor insulin secretion in SA men. The findings call for research to improve insulin secretion in early natural history of diabetes.

Sexual dimorphism in cardiometabolic health: the role of adipose tissue, muscle and liver

Obesity is associated with many adverse health effects, such as an increased cardiometabolic risk. Despite higher adiposity for a given BMI, premenopausal women are at lower risk of cardiometabolic disease than men of the same age. This cardiometabolic advantage in women seems to disappear after the menopause or when type 2 diabetes mellitus develops. Sexual dimorphism in substrate supply and utilization, deposition of excess lipids and mobilization of stored lipids in various key metabolic organs (such as adipose tissue, skeletal muscle and the liver) are associated with differences in tissue-specific insulin sensitivity and cardiometabolic risk profiles between men and women. Moreover, lifestyle-related factors and epigenetic and genetic mechanisms seem to affect metabolic complications and disease risk in a sex-specific manner. This Review provides insight into sexual dimorphism in adipose tissue distribution, adipose tissue, skeletal muscle and liver substrate metabolism and tissue-specific insulin sensitivity in humans, as well as the underlying mechanisms, and addresses the effect of these sex differences on cardiometabolic health. Additionally, this Review highlights the implications of sexual dimorphism in the pathophysiology of obesity-related cardiometabolic risk for the development of sex-specific prevention and treatment strategies.

Prenatal Nicotine Exposure Induces Low Birthweight and Hyperinsulinemia in Male Rats

Smoking during pregnancy is one of the causes of low birthweight. Ingestion of nicotine during pregnancy has various metabolic impacts on the fetus and offspring. According to the developmental origins of health and disease theory, low birthweight is a risk factor for developing various non-communicable diseases, including diabetes. We hypothesized that when nicotine-induced low-birthweight rats, when exposed to a high-fat diet (HFD) after growth, are predisposed to glucose intolerance as a result of a mismatch between the eutrophic environment and small body size. Therefore, we investigated whether hyperinsulinemia was caused by exposure of nicotine-induced low-birthweight rats to HFD, including whether this phenomenon exhibited possible sex differences. The average birthweight and body weight at weaning day of offspring from nicotine-administered dams was lower than those of controls. The offspring from nicotine-administered dams did not show rapid fat accumulation after exposure to HFD, and weight and body fat ratio of these animals did not differ from those of the controls. Blood glucose levels did not differ between the groups, but insulin levels increased only in male HFD-exposed offspring from nicotine-administered dams. Similarly, only in HFD-exposed male from nicotine-administered dams showed decreases in the insulin receptor expression in the liver. We conclude that male rats subjected to prenatal nicotine exposure develop hyperinsulinemia when exposed to HFD after growth. Our results suggest that decreased expression of insulin receptors in the liver may be involved in the mechanism underlying hyperinsulinemia in low-birthweight offspring, a phenomenon that appeared to exhibit a sex-specific bias.

Assessment of simple strategies for identifying undiagnosed diabetes and prediabetes in the general population

BACKGROUND AND AIMS

The rising tide of diabetes mellitus (DM) and prediabetes (PDM) is urgently calling for strategies easily applicable to anticipate diagnosis. We assessed the effectiveness of random capillary blood glucose (RCBG), administration of a validated DM risk questionnaire, or the combination of both.

MATERIALS AND METHODS

RCBG measurement and/or questionnaire administration were offered to all individuals presenting at gazebos organized during the World Diabetes Day or similar public initiatives on diabetes awareness. Subjects with suspicious DM or PDM were invited to the Diabetes Center (DC) for laboratory confirmation (fasting plasma glucose and HbA1c).

RESULTS

Among 8563 individuals without known diabetes undergoing RCBG measurement, 341 (4%) had suspicious values. Diagnosis of DM was confirmed in 36 (41.9%) of the 86 subjects who came to the DC and PDM was found in 40 (46.5%). Among 3351 subjects to whom the questionnaire was administered, 480 (14.3%) had suspicious scores. Diagnosis of DM was confirmed in 40 (10.1%) of the 397 who came to the DC and PDM was found in 214 (53.9%). These 3351 subjects also had RCBG measurement and 30 out of them had both tests positive. Among them, 27 subjects came to DC and DM was diagnosed in 17 (63.0%) and PDM was found in 9 (33.3%).

CONCLUSIONS

These data suggest that RCBG definitely outperforms the questionnaire to identify unknown DM and PDM. RCBG measurement, with questionnaire as an adjunctive tool, appears to be a simple, fast, and feasible opportunistic strategy in detecting undiagnosed DM and PDM.

Assessment of Health-Related Quality of Life Using EuroQoL-5 Dimension in Populations With Prediabetes, Diabetes, and Normal Glycemic Levels in Southwest China

Objectives: This study aimed to describe and compare health-related quality of life (HRQoL) among populations with normal glycemic levels, prediabetes, and diabetes in southwest China and to offer baseline data that can be easily compared to other regions in China or across countries. Methods: A quality of life survey based on the EuroQoL-5 Dimension-5 level (EQ-5D-5L) scale was conducted through face-to-face or telephone interviews. A total of 403 respondents with diabetes, 404 with prediabetes, and 398 with normal blood glucose were enrolled in the survey. Propensity score matching (PSM) was used to decrease the bias of three groups, conditioned on age and gender, body mass index (BMI), and household income. For the three groups, we matched two groups first and then matched the result with the third group. Differences among groups were compared by chi-square test one-way ANOVA after adjusting by PSM. Results: In general, the blood glucose of people with diabetes was generally well-controlled in southwest China, but they were often accompanied by the circulatory system and nutritional metabolic diseases. Ninety-nine individuals from each group were matched. The EuroQoL-5 Dimension index of the population with normal glycemic levels, prediabetes, and patients with diabetes was 0.901, 0.948, and 0.897. The EuroQol-visual analog scales (EQ-VAS) scores of each group above were 73.76, 77.45, and 68.34. HRQoL in males was higher than that of females in the three study groups. The results after PSM were consistent with that before matching. Conclusion: There was a general trend that patients were associated with a decline of HRQoL from the prediabetic population, population with normal glycemic levels to diabetic population. Pain/discomfort and anxiety/depression might not be specific for the population with or without diabetes.

The Metabolic Effects of Cynara Supplementation in Overweight and Obese Class I Subjects with Newly Detected Impaired Fasting Glycemia: A Double-Blind, Placebo-Controlled, Randomized Clinical Trial

Impaired fasting glucose (IFG) is a condition that precedes diabetes and increases the risk of developing it. Studies support the hypoglycemic effect of Cynarascolymus (Cs) extracts due to the content of chlorogenic acid, which is a potent inhibitor of glucose 6-phosphate translocase and of dicaffeoylquinic acid derivatives that modulate the activity of alpha-glucosidase. Given this background, we investigated whether a new highly standardized Cs extract could improve glycemic control, insulin sensitivity and other metabolic parameters (total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) Triglycerides, Apolipo protein B (ApoB), Apolipo protein A (ApoA), waist circumference, visceral adipose tissue (VAT) by dual-energy X-ray absorptiometry (DXA) in overweight subjects with newly diagnosed IFG. Fifty-four subjects (females/males 26/28, mean ± SD age 51.5 ± 6.2) were randomly assigned to the supplemented group (n = 27) and placebo (n = 27). After multiple testing correction, statistically significant interactions between time and group were observed for the primary endpoint glycemia (β = 0.36, p < 0.0001) and for the secondary endpoints HDL (β = −0.10, p < 0.0001), total cholesterol/HDL (β = 0.27, p < 0.0001), LDL (β = 0.15, p = 0.005), LDL/HDL (β = 0.23, p = 0.001), insulin (β = 1.28, p = 0.04), glycated hemoglobin (β = 0.21, p = 0.0002), A1c-derived average glucose (β = 0.34, p = 0.0002), ApoB (β = 6.00, p = 0.01), ApoA (β = −4.50, p = 0.04), ApoB/ApoA (β = 0.08, p = 0.003), waist circumference (β = 1.89, p = 0.05), VATβ = 222.37, p = 0.005). In conclusion, these results confirm that Cs supplementation has a significant effect on metabolic parameters in IFG patients.

Maternal diabetes and the risk of feeding and eating disorders in offspring: a national population-based cohort study

INTRODUCTION

Previous studies have suggested that maternal diabetes may have programming effect on fetal brain development. However, little is known about the association between maternal diabetes and neurodevelopmental disorders in offspring that mainly manifest in infancy or early childhood. We aimed to examine the association between maternal diabetes before or during pregnancy and feeding and eating disorders (FED) in offspring.

RESEARCH DESIGN AND METHODS

This population-based cohort study included 1 193 891 singletons born in Denmark during 1996-2015. These children were followed from birth until the onset of FED, the sixth birthday, death, emigration, or 31 December 2016, whichever came first. Relative risk of FED was estimated by HRs using Cox proportional hazards model.

RESULTS

A total of 40 867 (3.4%) children were born to mothers with diabetes (20 887 with pregestational diabetes and 19 980 with gestational diabetes). The incidence rates of FED were 6.8, 4.6 and 2.9 per 10 000 person-years among children of mothers with pregestational diabetes, gestational diabetes and no diabetes, respectively. Offspring of mothers with diabetes had a 64% increased risk of FED (HR 1.64; 95% CI 1.36 to 1.99; p<0.001). The HR for maternal pregestational diabetes and gestational diabetes was 2.01 (95% CI 1.59 to 2.56; p<0.001) and 1.28 (95% CI 0.95 to 1.72; p=0.097), respectively. The increased risk was more pronounced among offspring of mothers with diabetic complications (HR 2.97; 95% CI 1.54 to 5.72; p=0.001).

CONCLUSIONS

Maternal diabetes was associated with an increased risk of FED in offspring in infancy and early childhood. Our findings can inform clinical decisions for better management of maternal diabetes, in particular before pregnancy, which can reduce early neurodevelopmental problems in the offspring.

Sex differences in metabolic regulation and diabetes susceptibility

Gender and biological sex impact the pathogenesis of numerous diseases, including metabolic disorders such as diabetes. In most parts of the world, diabetes is more prevalent in men than in women, especially in middle-aged populations. In line with this, considering almost all animal models, males are more likely to develop obesity, insulin resistance and hyperglycaemia than females in response to nutritional challenges. As summarised in this review, it is now obvious that many aspects of energy balance and glucose metabolism are regulated differently in males and females and influence their predisposition to type 2 diabetes. During their reproductive life, women exhibit specificities in energy partitioning as compared with men, with carbohydrate and lipid utilisation as fuel sources that favour energy storage in subcutaneous adipose tissues and preserve them from visceral and ectopic fat accumulation. Insulin sensitivity is higher in women, who are also characterised by higher capacities for insulin secretion and incretin responses than men; although, these sex advantages all disappear when glucose tolerance deteriorates towards diabetes. Clinical and experimental observations evidence the protective actions of endogenous oestrogens, mainly through oestrogen receptor α activation in various tissues, including the brain, the liver, skeletal muscle, adipose tissue and pancreatic beta cells. However, beside sex steroids, underlying mechanisms need to be further investigated, especially the role of sex chromosomes, fetal/neonatal programming and epigenetic modifications. On the path to precision medicine, further deciphering sex-specific traits in energy balance and glucose homeostasis is indeed a priority topic to optimise individual approaches in type 2 diabetes prevention and treatment.

Prevalence of Prediabetes Among Adolescents and Young Adults in the United States, 2005-2016

IMPORTANCE

Individuals with prediabetes are at increased risk of developing type 2 diabetes, chronic kidney disease, and cardiovascular disease. The incidence and prevalence of type 2 diabetes in the US adolescent population have increased in the last decade. Therefore, it is important to monitor the prevalence of prediabetes and varying levels of glucose tolerance to assess the future risk of type 2 diabetes in the youngest segment of the population.

OBJECTIVE

To examine the prevalence of impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and increased glycated hemoglobin A1c (HbA1c) levels in US adolescents (aged 12-18 years) and young adults (aged 19-34 years) without diabetes.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional analyses of the 2005-2016 National Health and Nutrition Examination Survey assessed a population-based sample of adolescents and young adults who were not pregnant, did not have diabetes, and had measured fasting plasma glucose, 2-hour plasma glucose after a 75-g oral glucose tolerance test, and HbA1c levels. Analysis began in April 2017.

MAIN OUTCOMES AND MEASURES

Impaired fasting glucose was defined as fasting plasma glucose of 100 mg/dL to less than 126 mg/dL, IGT as 2-hour plasma glucose of 140 mg/dL to less than 200 mg/dL, and increased HbA1c level as HbA1c level between 5.7% and 6.4%. The prevalence of IFG, isolated IFG, IGT, isolated IGT, increased HbA1c level, isolated increased HbA1c level, and prediabetes (defined as having IFG, IGT, or increased HbA1c level) were estimated. Fasting insulin levels and cardiometabolic risk factors across glycemic abnormality phenotypes were also compared. Obesity was defined as having age- and sex-specific body mass index (calculated as weight in kilograms divided by height in meters squared) in the 95th percentile or higher in adolescents or 30 or higher in young adults.

RESULTS

Of 5786 individuals, 2606 (45%) were adolescents and 3180 (55%) were young adults. Of adolescents, 50.6% (95% CI, 47.6%-53.6%) were boys, and 50.6% (95% CI, 48.8%-52.4%) of young adults were men. Among adolescents, the prevalence of prediabetes was 18.0% (95% CI, 16.0%-20.1%) and among young adults was 24.0% (95% CI, 22.0%-26.1%). Impaired fasting glucose constituted the largest proportion of prediabetes, with prevalence of 11.1% (95% CI, 9.5%-13.0%) in adolescents and 15.8% (95% CI, 14.0%-17.9%) in young adults. In multivariable logistic models including age, sex, race/ethnicity, and body mass index, the predictive marginal prevalence of prediabetes was significantly higher in male than in female individuals (22.5% [95% CI, 19.5%-25.4%] vs 13.4% [95% CI, 10.8%-16.5%] in adolescents and 29.1% [95% CI, 26.4%-32.1%] vs 18.8% [95% CI, 16.5%-21.3%] in young adults). Prediabetes prevalence was significantly higher in individuals with obesity than in those with normal weight (25.7% [95% CI, 20.0%-32.4%] vs 16.4% [95% CI, 14.3%-18.7%] in adolescents and 36.9% [95% CI, 32.9%-41.1%] vs 16.6% [95% CI, 14.2%-19.4%] in young adults). Compared with persons with normal glucose tolerance, adolescents and young adults with prediabetes had significantly higher non-high-density lipoprotein cholesterol levels, systolic blood pressure, central adiposity, and lower insulin sensitivity (P < .05 for all).

CONCLUSIONS AND RELEVANCE

In the United States, about 1 of 5 adolescents and 1 of 4 young adults have prediabetes. The adjusted prevalence of prediabetes is higher in male individuals and in people with obesity. Adolescents and young adults with prediabetes also present an unfavorable cardiometabolic risk profile, putting them both at increased risk of type 2 diabetes and cardiovascular diseases.

Activation of brown adipose tissue in diet-induced thermogenesis is GC-C dependent

Uroguanylin (UGN) is released from the intestine after a meal. When applied in brain ventricles, UGN increases expression of markers of thermogenesis in brown adipose tissue (BAT). Therefore, we determine the effects of its receptor, guanylate cyclase C (GC-C), on mouse interscapular BAT (iBAT) activity during diet-induced thermogenesis (DIT). The activation of iBAT after a meal is diminished in GC-C KO mice, decreased in female wild type (WT) mice, and abolished in old WT animals. The activation of iBAT after a meal is the highest in male WT animals which leads to an increase in GC-C expression in the hypothalamus, an increase in iBAT volume by aging, and induction of iBAT markers of thermogenesis. In contrast to iBAT activation after a meal, iBAT activation after a cold exposure could still exist in GC-C KO mice and it is significantly higher in female WT mice. The expression of GC-C in the proopiomelanocortin neurons of the arcuate nucleus of the hypothalamus but not in iBAT suggests central regulation of iBAT function. The iBAT activity during DIT has significantly reduced in old mice but an intranasal application of UGN leads to an increase in iBAT activity in a dose-dependent manner which is in strong negative correlation to glucose concentration in blood. This activation was not present in GC-C KO mice. Our results suggest the physiological role of GC-C on the BAT regulation and its importance in the regulation of glucose homeostasis and the development of new therapy for obesity and insulin resistance.

Maturity-Onset Diabetes of the Young Identified Among Algerian Probands with Early-Onset Diabetes

AIM

To investigate the prevalence of variants within selected maturity-onset diabetes of the young (MODY)-genes among Algerian patients initially diagnosed with type 1 diabetes (T1D) or type 2 diabetes (T2D), yet presenting with a MODY-like phenotype.

METHODS

Eight unrelated patients with early-onset diabetes (before 30 years) and six relatives with diabetes were examined by targeted re-sequencing for variants in genes known to be involved in MODY (HNF1A, GCK, HNF4A, HNF1B, INS, ABCC8, KCNJ1). Clinical data for probands were retrieved from hospital records.

RESULTS

A total of 12 variants were identified, of which three were classified as pathogenic and one as a variant of uncertain clinical significance (VUS). Two of the pathogenic variants were found in GCK (p.Gly261Arg and p.Met210Lys, respectively) in one proband each and the remaining pathogenic variant was found in HNF1B (p.Gly76Cys) in a proband also carrying the VUS in HNF1A (p.Thr156Met).

CONCLUSION

Variants in known MODY-genes can be the cause of early-onset diabetes in Algerians diagnosed with T1D or T2D among patients presenting with a MODY-like phenotype; thus, genetic screening should be considered.

Time trends in diabetes mellitus in Jordan between 1994 and 2017

AIM

The prevalence of diabetes has been increasing over the past few decades. The objective of this study is to assess the time trends in diabetes between 1994 and 2017 in Jordan.

METHODS

Surveys were conducted in 1994, 2004, 2009 and 2017 by the same investigators using generally similar methods. Fasting blood glucose was measured in all surveys. Variables were obtained using structured questionnaires designed specifically for the surveys. Crude and age-specific diabetes prevalence rates were derived for each sex, together with overall, crude and age-standardized prevalence rates.

RESULTS

The prevalence of diabetes in men aged ≥ 25 years increased from 14.2% in 1994 to 18.3% in 2004, 26.8% in 2009 and 32.4% in 2017. The corresponding prevalence rates in women were 12.3%, 16.9%, 18.8%, and 18.1%, respectively. The overall age-standardized prevalence rate increased from 13.0% in 1994 to 17.1% in 2004, 22.2% in 2009 and 23.7% in 2017. Known diabetes in the 2017 survey accounted for 82.6% of people with diabetes. A HbA_1c of < 59 mmol/mol (7.5%) was observed in 41.4% of participants with known diabetes.

CONCLUSION

The results showed a high prevalence of diabetes in Jordan among people aged ≥ 25 years. Prevalence increased from 1994 to 2009, but slowed thereafter. The increase was greater in men than in women. Previously diagnosed diabetes accounted for a high percentage of people with diabetes in all surveys and was highest in 2017 survey, suggesting that the national strategy against diabetes has brought some benefits. Efforts should be made to improve glycaemic control in people with diabetes.

Reappraisal of variants previously linked with sudden infant death syndrome: results from three population-based cohorts

We aimed to investigate the pathogenicity of cardiac ion channel variants previously associated with SIDS. We reviewed SIDS-associated variants previously reported in databases and the literature in three large population-based cohorts; The ExAC database, the Inter99 study, and the UK Biobank (UKBB). Variants were classified according to the American College of Medical Genetics and Genomics (ACMG) guidelines. Of the 92 SIDS-associated variants, 59 (64%) were present in ExAC, 18 (20%) in Inter99, and 24 (26%) in UKBB. Using the Inter99 cohort, we found no difference in J-point amplitude and QTc-interval between carriers and non-carriers for 14/18 variants. There was no difference in the risk of syncope (P = 0.32), malignant ventricular arrhythmia (P = 0.96), and all-cause mortality (P = 0.59) between carriers and non-carriers. The ACMG guidelines reclassified 75% of all variants as variant-of-uncertain significance, likely benign, and benign. We identified ~2/3 of variants previously associated with SIDS and found no significant associations with electrocardiographic traits, syncope, malignant ventricular arrhythmia, or all-cause mortality. These data indicate that many of these variants are not highly penetrant, monogenic causes of SIDS and underline the importance of frequent reappraisal of genetic variants to avoid future misdiagnosis.

Sequencing reveals protective and pathogenic effects on development of diabetes of rare GLIS3 variants

Background

Based on the association of common GLIS3 variants with various forms of diabetes and the biological role of GLIS3 in beta-cells, we sequenced GLIS3 in non-diabetic and diabetic Danes to investigate the effect of rare missense variants on glucose metabolism.

Methods

We sequenced 53 patients with maturity-onset diabetes of the young (MODY), 5,726 non-diabetic participants, 2,930 patients with newly diagnosed type 2 diabetes and 206 patients with glutamic acid decarboxylase antibody (GADA) -positive diabetes.

Results

In total we identified 86 rare (minor allele frequency < 0.1%) missense variants. None was considered causal for the presence of MODY. Among patients with type 2 diabetes, we observed a higher prevalence of rare GLIS3 missense variants (2.5%) compared to non-diabetic individuals (1.8%) (odds ratio of 1.37 (interquartile range:1.01–1.88, p = 0.04)). A significantly increased HbA1c was found among patients with type 2 diabetes and with GADA-positive diabetes carrying rare GLIS3 variants compared to non-carriers of rare GLIS3 variants with diabetes (p = 0.02 and p = 0.004, respectively). One variant (p.I28V) was found to have a minor allele frequency of only 0.03% among patients with type 2 diabetes compared to 0.2% among non-diabetic individuals suggesting a protective function (odds ratio of 0.20 (interquartile range: 0.005–1.4, p = 0.1)), an effect which was supported by publically available data. This variant was also associated with a lower level of fasting plasma glucose among non-diabetic individuals (p = 0.046).

Conclusion

Rare missense variants in GLIS3 associates nominally with increased level of HbA1c and increased risk of developing type 2 diabetes. In contrast, the rare p.I28V variant associate with reduced level of fasting plasma glucose and may be protective against type 2 diabetes.

Health risks and interventions in prediabetes: A review

Prediabetes is a condition which appears prior to the development of diabetes in which blood glucose is abnormally high but do not reach the diagnostic threshold of type 2 diabetes mellitus. It is characterized by a cluster of metabolic abnormalities viz. dysglycemia, dyslipidemia, hypertension, physical inactivity, obesity, insulin resistance, procoagulant state, endothelial dysfunction, oxidative stress and inflammation, placing prediabetic subjects to an increased risk for diabetes and its complications. Recent studies demonstrate that complications of diabetes i.e. microvascular and macrovascular complications may manifest in some prediabetic subjects. This article reviews prediabetes-related risk factors and health issues. In addition, this article also highlights the interventions to prevent the development of diabetes in prediabetic subjects.

Increased frequency of rare missense PPP1R3B variants among Danish patients with type 2 diabetes

Background

PPP1R3B has been suggested as a candidate gene for monogenic forms of diabetes as well as type 2 diabetes (T2D) due to its association with glycaemic trait and its biological role in glycogen synthesis.

Objectives

To study if rare missense variants in PPP1R3B increase the risk of maturity onset diabetes of the young (MODY), T2D or affect measures of glucose metabolism.

Method

Targeted resequencing of PPP1R3B was performed in 8,710 samples; MODY patients with unknown etiology (n = 54), newly diagnosed patients with T2D (n = 2,930) and population-based control individuals (n = 5,726, of whom n = 4,569 had normal glucose tolerance). All population-based sampled individuals were examined using an oral glucose tolerance test.

Results

Among n = 396 carriers, we identified twenty-three PPP1R3B missense mutations, none of which segregated with MODY. The burden of likely deleterious PPP1R3B variants was significantly increased with a total of 17 carriers among patients with T2D (0.58% (95% CI: 0.36–0.93)) compared to 18 carriers among non-diabetic individuals (0.31% (95% CI: 0.20–0.49)), resulting in an increased risk of T2D (OR (95% CI) = 2.57 (1.14–5.79), p = 0.02 (age and sex adjusted)). Furthermore, carriers with diabetes had less abdominal fat and a higher serum concentration of LDL-cholesterol compared to patients with T2D without rare missense PPP1R3B variants. In addition, non-diabetic carriers had a higher birth weight compared to non-carriers.

Conclusion

Rare missense PPP1R3B variants may predispose to T2D.

Hypertension genetic risk score is associated with burden of coronary heart disease among patients referred for coronary angiography

BACKGROUND

Recent GWAS studies have identified more than 300 SNPs associated with variation in blood pressure. We investigated whether a genetic risk score constructed from these variants is associated with burden of coronary heart disease.

METHODS

From 2010-2014, 4,809 individuals admitted to coronary angiography in Capital Region of Copenhagen were genotyped. We calculated hypertension GRS comprised of GWAS identified SNPs associated with blood pressure. We performed logistic regression analyses to estimate the risk of hypertension and prevalent CHD. We also assessed the severity of CHD associated with the GRS. The analyses were performed using GRS quartiles. We used the Inter99 cohort to validate our results and to investigate for possible pleiotropy for the GRS with other CHD risk factors.

RESULTS

In COGEN, adjusted odds ratios comparing the 2nd, 3rd and 4th cumulative GRS quartiles with the reference were 1.12(95% CI 0.95-1.33), 1.35(95% CI 1.14-1.59) and 1.29(95% CI 1.09-1.53) respectively, for prevalent CHD. The adjusted multinomial logistic regression showed that 3rd and 4th GRS quartiles were associated with increased odds of developing two(OR 1.33, 95% CI 1.04-1.71 and OR 1.36, 95% CI 1.06-1.75, respectively) and three coronary vessel disease(OR 1.77, 95% CI 1.36-2.30 and OR 1.65, 95% CI 1.26-2.15, respectively). Similar results for incident CHD were observed in the Inter99 cohort. The hypertension GRS did not associate with type 2 diabetes, smoking, BMI or hyperlipidemia.

CONCLUSION

Hypertension GRS quartiles were associated with an increased risk of hypertension, prevalent CHD, and burden of coronary vessel disease in a dose-response pattern. We showed no evidence for pleiotropy with other risk factors for CHD.

Association of characteristics of people with type 2 diabetes mellitus with discordant values of fasting glucose and HbA1c

BACKGROUND

Primary care physicians frequently encounter people with type 2 diabetes mellitus (T2DM) with discordant values for fasting glucose and HbA1c. The aim of this study was to identify the prevalence and characteristics of people in whom blood glucose and HbA1c did not match.

METHODS

Overall, 64 553 people with T2DM from 939 general or internal medicine practices (Disease Analyzer database, Germany; January 2013-December 2015) were analyzed. Multivariable logistic regression models were used to identify associations between baseline clinical characteristics, comorbidity, and glucose-lowering treatment and discordance of fasting glucose and HbA1c values measured at the same visit.

RESULTS

Overall, 8582 (13%) patients had fasting glucose ≥140 mg/dL and HbA1c <7% (<53 mmol/mol), and 6508 (10%) had HbA1c ≥7% (≥53 mmol/mol) and fasting glucose <140 mg/dL. Using patients with both fasting glucose <140 mg/dL and HbA1c <7% as the reference (n = 31 834; 49%), solitary high fasting glucose values (and HbA1c <7%) were positively associated with higher age, male sex, longer diabetes duration, obesity, liver disease, low estimated glomerular filtration rate (eGFR), and glucose-lowering treatment. High HbA1c (and fasting glucose <140 mg/dL) was positively related to longer diabetes duration, obesity, neuropathy, retinopathy, low eGFR, and insulin treatment. There were lower odds of having solitary increased HbA1c ≥7% (fasting glucose <140 mg/dL) with higher age, hypertension, depression, and the number of diabetes patients (>200) per practice.

CONCLUSIONS

A considerable number of people with T2DM in primary care practices have discordant fasting blood glucose and HbA1c values. People who have discordant glycemic values have different characteristics.

Prevalence and Impact of Diabetes Mellitus on the Frozen Shoulder

OBJECTIVES

The objective of this study was to estimate the prevalence of undiagnosed diabetes mellitus in patients with newly diagnosed frozen shoulder (FS) and study whether diabetes mellitus increases the severity of FS disease.

METHODS

Patients with newly diagnosed FS were consecutively included in this case-control study. Patients who were not already diagnosed as having diabetes mellitus were invited to be tested with the hemoglobin A1c blood sample test. The study population was compared with a control group, consisting of five individuals from the general population matched on age and sex. The passive range of motion, Oxford Shoulder Score, and visual analog scale (VAS) for average and maximum daily pain was recorded for all of the patients in the study group.

RESULTS

A total of 235 patients were included, 34 (14%) of whom were diagnosed as having diabetes mellitus before the examination. Of the remaining 201 patients, 122 (61%) agreed to be tested for diabetes mellitus. None of the tested patients had undiagnosed diabetes mellitus. This was not significantly different from the prevalence in the matched control population (P = 0.09). There was no difference between patients with and without diabetes mellitus in average daily VAS (P = 0.46) nor maximum daily VAS (P = 0.44). The Oxford Shoulder Score was similar in the two groups (P = 0.23) as was the range of motion.

CONCLUSIONS

The prevalence of undiagnosed diabetes mellitus is low in patients with FS and does not differ from the general population. Diabetes mellitus does not seem to affect patients' perceived severity of an FS.

Development of type 2 diabetes mellitus in people with intermediate hyperglycaemia

BACKGROUND

Intermediate hyperglycaemia (IH) is characterised by one or more measurements of elevated blood glucose concentrations, such as impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and elevated glycosylated haemoglobin A1c (HbA1c). These levels are higher than normal but below the diagnostic threshold for type 2 diabetes mellitus (T2DM). The reduced threshold of 5.6 mmol/L (100 mg/dL) fasting plasma glucose (FPG) for defining IFG, introduced by the American Diabetes Association (ADA) in 2003, substantially increased the prevalence of IFG. Likewise, the lowering of the HbA1c threshold from 6.0% to 5.7% by the ADA in 2010 could potentially have significant medical, public health and socioeconomic impacts.

OBJECTIVES

To assess the overall prognosis of people with IH for developing T2DM, regression from IH to normoglycaemia and the difference in T2DM incidence in people with IH versus people with normoglycaemia.

SEARCH METHODS

We searched MEDLINE, Embase, ClincialTrials.gov and the International Clinical Trials Registry Platform (ICTRP) Search Portal up to December 2016 and updated the MEDLINE search in February 2018. We used several complementary search methods in addition to a Boolean search based on analytical text mining.

SELECTION CRITERIA

We included prospective cohort studies investigating the development of T2DM in people with IH. We used standard definitions of IH as described by the ADA or World Health Organization (WHO). We excluded intervention trials and studies on cohorts with additional comorbidities at baseline, studies with missing data on the transition from IH to T2DM, and studies where T2DM incidence was evaluated by documents or self-report only.

DATA COLLECTION AND ANALYSIS

One review author extracted study characteristics, and a second author checked the extracted data. We used a tailored version of the Quality In Prognosis Studies (QUIPS) tool for assessing risk of bias. We pooled incidence and incidence rate ratios (IRR) using a random-effects model to account for between-study heterogeneity. To meta-analyse incidence data, we used a method for pooling proportions. For hazard ratios (HR) and odds ratios (OR) of IH versus normoglycaemia, reported with 95% confidence intervals (CI), we obtained standard errors from these CIs and performed random-effects meta-analyses using the generic inverse-variance method. We used multivariable HRs and the model with the greatest number of covariates. We evaluated the certainty of the evidence with an adapted version of the GRADE framework.

MAIN RESULTS

We included 103 prospective cohort studies. The studies mainly defined IH by IFG5.6 (FPG mmol/L 5.6 to 6.9 mmol/L or 100 mg/dL to 125 mg/dL), IFG6.1 (FPG 6.1 mmol/L to 6.9 mmol/L or 110 mg/dL to 125 mg/dL), IGT (plasma glucose 7.8 mmol/L to 11.1 mmol/L or 140 mg/dL to 199 mg/dL two hours after a 75 g glucose load on the oral glucose tolerance test, combined IFG and IGT (IFG/IGT), and elevated HbA1c (HbA1c5.7: HbA1c 5.7% to 6.4% or 39 mmol/mol to 46 mmol/mol; HbA1c6.0: HbA1c 6.0% to 6.4% or 42 mmol/mol to 46 mmol/mol). The follow-up period ranged from 1 to 24 years. Ninety-three studies evaluated the overall prognosis of people with IH measured by cumulative T2DM incidence, and 52 studies evaluated glycaemic status as a prognostic factor for T2DM by comparing a cohort with IH to a cohort with normoglycaemia. Participants were of Australian, European or North American origin in 41 studies; Latin American in 7; Asian or Middle Eastern in 50; and Islanders or American Indians in 5. Six studies included children and/or adolescents.Cumulative incidence of T2DM associated with IFG5.6, IFG6.1, IGT and the combination of IFG/IGT increased with length of follow-up. Cumulative incidence was highest with IFG/IGT, followed by IGT, IFG6.1 and IFG5.6. Limited data showed a higher T2DM incidence associated with HbA1c6.0 compared to HbA1c5.7. We rated the evidence for overall prognosis as of moderate certainty because of imprecision (wide CIs in most studies). In the 47 studies reporting restitution of normoglycaemia, regression ranged from 33% to 59% within one to five years follow-up, and from 17% to 42% for 6 to 11 years of follow-up (moderate-certainty evidence).Studies evaluating the prognostic effect of IH versus normoglycaemia reported different effect measures (HRs, IRRs and ORs). Overall, the effect measures all indicated an elevated risk of T2DM at 1 to 24 years of follow-up. Taking into account the long-term follow-up of cohort studies, estimation of HRs for time-dependent events like T2DM incidence appeared most reliable. The pooled HR and the number of studies and participants for different IH definitions as compared to normoglycaemia were: IFG5.6: HR 4.32 (95% CI 2.61 to 7.12), 8 studies, 9017 participants; IFG6.1: HR 5.47 (95% CI 3.50 to 8.54), 9 studies, 2818 participants; IGT: HR 3.61 (95% CI 2.31 to 5.64), 5 studies, 4010 participants; IFG and IGT: HR 6.90 (95% CI 4.15 to 11.45), 5 studies, 1038 participants; HbA1c5.7: HR 5.55 (95% CI 2.77 to 11.12), 4 studies, 5223 participants; HbA1c6.0: HR 10.10 (95% CI 3.59 to 28.43), 6 studies, 4532 participants. In subgroup analyses, there was no clear pattern of differences between geographic regions. We downgraded the evidence for the prognostic effect of IH versus normoglycaemia to low-certainty evidence due to study limitations because many studies did not adequately adjust for confounders. Imprecision and inconsistency required further downgrading due to wide 95% CIs and wide 95% prediction intervals (sometimes ranging from negative to positive prognostic factor to outcome associations), respectively.This evidence is up to date as of 26 February 2018.

AUTHORS' CONCLUSIONS

Overall prognosis of people with IH worsened over time. T2DM cumulative incidence generally increased over the course of follow-up but varied with IH definition. Regression from IH to normoglycaemia decreased over time but was observed even after 11 years of follow-up. The risk of developing T2DM when comparing IH with normoglycaemia at baseline varied by IH definition. Taking into consideration the uncertainty of the available evidence, as well as the fluctuating stages of normoglycaemia, IH and T2DM, which may transition from one stage to another in both directions even after years of follow-up, practitioners should be careful about the potential implications of any active intervention for people 'diagnosed' with IH.

Rare truncating variants in the sarcomeric protein titin associate with familial and early-onset atrial fibrillation

A family history of atrial fibrillation constitutes a substantial risk of developing the disease, however, the pathogenesis of this complex disease is poorly understood. We perform whole-exome sequencing on 24 families with at least three family members diagnosed with atrial fibrillation (AF) and find that titin-truncating variants (TTNtv) are significantly enriched in these patients (P = 1.76 × 10⁻⁶). This finding is replicated in an independent cohort of early-onset lone AF patients (n = 399; odds ratio = 36.8; P = 4.13 × 10⁻⁶). A CRISPR/Cas9 modified zebrafish carrying a truncating variant of titin is used to investigate TTNtv effect in atrial development. We observe compromised assembly of the sarcomere in both atria and ventricle, longer PR interval, and heterozygous adult zebrafish have a higher degree of fibrosis in the atria, indicating that TTNtv are important risk factors for AF. This aligns with the early onset of the disease and adds an important dimension to the understanding of the molecular predisposition for AF.

Common genetic variants in structural proteins contribute to risk of atrial fibrillation (AF). Here, using whole-exome sequencing, the authors identify rare truncating variants in TTN that associate with familial and early-onset AF and show defects in cardiac sarcomere assembly in ttn.2-mutant zebrafish.

Sex differences in metabolism and cardiometabolic disorders

PURPOSE OF REVIEW

Sex differences are pervasive in metabolic and cardiovascular traits, yet they have often been ignored in human and animal model research. Sex differences can arise from reversible hormonal effects, from irreversible organizational (developmental) processes, and from gene expression differences from the X and Y chromosomes. We briefly review our current understanding of the impact of these factors in metabolic traits and disorders, with an emphasis on the recent literature.

RECENT FINDINGS

Novel sex differences continue to be identified for metabolic and cardiovascular traits. For example, it is now clear that gut microbiota tend to differ between men and women, with potentially large implications for disease susceptibility. Also, tissue-specific gene regulation differs between men and women, contributing to differential metabolism. These new insights will open up personalized therapeutic avenues for cardiometabolic diseases.

SUMMARY

Sex differences in body fat distribution, glucose homeostasis, insulin signaling, ectopic fat accumulation, and lipid metabolism during normal growth and in response to hormonal or nutritional imbalance are mediated partly through sex hormones and the sex chromosome complement. Most of these differences are mediated in a tissue-specific manner. Important future goals are to better understand the interactions between genetic variation and sex differences, and to bring an understanding of sex differences into clinical practice.

Contributions of A1c, fasting plasma glucose, and 2-hour plasma glucose to prediabetes prevalence: NHANES 2011-2014

PURPOSE

Our goal was to characterize the contributions of A1c, fasting plasma glucose, and 2-hour plasma glucose to prediabetes prevalence and to characterize how those contributions differ among U.S. population subgroups.

METHODS

In the 2011-2014 National Health and Nutrition Examination Survey, a nationally representative sample of the U.S. population, among participants without diabetes (N = 3387), we created area-proportional three-Venn diagrams showing the proportion above the prediabetes cutpoint for each of the three markers in the overall population and in subgroups defined by age, race/ethnicity, sex, and body mass index.

RESULTS

In the overall population, 28.3% had fasting plasma glucose above the prediabetes cutpoint, 21.7% had A1c above the prediabetes cutpoint, and 13.3% had 2-hour plasma glucose above the prediabetes cutpoint. Adolescents and young adults tended to have only one marker exceed the prediabetes cutpoint, while older age groups tended to have multiple markers above the prediabetes cutpoint. For non-Hispanic whites, non-Hispanic blacks, non-Hispanic Asians, and Mexican-Americans, the unadjusted total percent above the A1c cutpoint was 19.3%, 36.4%, 20.5%, and 21.4%, respectively.

CONCLUSIONS

We provide a graphic reference showing fasting plasma glucose was the largest contributor to prediabetes prevalence in the overall population, followed by A1c and then 2-hour plasma glucose.

Brugada Syndrome-Associated Genetic Loci Are Associated With J-Point Elevation and an Increased Risk of Cardiac Arrest

Introduction: A previous genome-wide association study found three genetic loci, rs9388451, rs10428132, and rs11708996, to increase the risk of Brugada Syndrome (BrS). Since the effect of these loci in the general population is unknown, we aimed to investigate the effect on electrocardiogram (ECG) parameters and outcomes in the general population.

Materials and Methods: A cohort of 6,161 individuals (median age 45 [interquartile range (IQR) 40–50] years, 49% males), with available digital ECGs, was genotyped and subsequently followed for a median period of 13 [IQR 12.6–13.4] years. Data on outcomes were collected from Danish administrative healthcare registries. Furthermore, ~400,000 persons from UK Biobank were investigated for associations between the three loci and cardiac arrest/ventricular fibrillation (VF).

Results: Homozygote carriers of the C allele in rs6800541 intronic to SCN10A had a significantly larger J-point elevation (JPE) compared with wildtype carriers (11 vs. 6 μV, P < 0.001). There was an additive effect of carrying multiple BrS-associated risk alleles with an increased JPE in lead V1. None of the BrS-associated genetic loci predisposed to syncope, atrial fibrillation, or total mortality in the general Danish population. The rs9388451 genetic locus adjacent to the HEY2 gene was associated with cardiac arrest/VF in an analysis using the UK Biobank study (odds ratio = 1.13 (95% confidence interval: 1.08–1.18), P = 0.006).

Conclusions: BrS-associated risk alleles increase the JPE in lead V1 in an additive manner, but was not associated with increased mortality or syncope in the general population of Denmark. However, the HEY2 risk allele increased the risk of cardiac arrest/VF in the larger population study of UK Biobank indicating an important role of this common genetic locus.