Lean diabetes in middle-aged adults: A joint analysis of the German DIVE and DPV registries

Socioeconomic gradient of lean diabetes in India: Evidence from National Family Health Survey, 2019-21

Diabetes is a global public health challenge, particularly in India, affecting millions. Among diabetic patients, lean type 2 diabetes is a severe subtype with higher microvascular complication risks. While studies on the prevalence, variations and risk factors of diabetes are increasingly available, there has been limited research on the prevalence, variations, and socioeconomic disparities of lean diabetes in India. This study used NFHS-5 microdata, and lean diabetes is defined as those with a BMI level of under 25 and random blood glucose levels of over 200 or under diabetic medication. Descriptive and multivariate analyses were conducted to understand lean diabetes variations and related factors. Socioeconomic disparities were measured using concentration curves and the concentration index. The study unveiled important insights into lean diabetes in India. 8.2% of men and 6.0% of women had elevated blood glucose levels, indicating a significant diabetes burden. Notably, 2.9% of men and 2.4% of women were diagnosed with lean diabetes. Among type 2 diabetics, 52.56% of males and 43.57% of females had lean type 2 diabetes. Lean diabetes prevalence varied from 11.6% in the poorest quintile to 1.1% in the richest. The odds of lean type 2 diabetes among those in the poorest quintile was 6.7 compared to the richest quintile. The concentration index of lean type 2 diabetes was -0.42 for men and -0.39 for women, suggesting a disproportionate impact on lower socioeconomic groups. This study advances our understanding of the complex interplay between socioeconomic factors and lean type 2 diabetes in India. To address the rising burden of lean diabetes among lower socioeconomic strata, policymakers and healthcare professionals must prioritise initiatives enhancing healthcare access, promoting healthy lifestyles, and ensuring effective diabetes management. By addressing socioeconomic disparities and implementing interventions for vulnerable populations, India can reduce diabetes-related mortality and enhance its citizens' overall health.

Interactions between physical activity and psychological factors in the association with the risk of lean type 2 diabetes mellitus

Background: The extent to which physical activity and psychological factors may affect the risk of diabetes mellitus among lean individuals remains unclear.Purpose: This study aimed to investigate the associations of total physical activity (TPA) and psychological factors with lean type 2 diabetes mellitus (T2DM) risk.Research Design: A prospective cohort study.Study Sample: The study population included 1,945 Korean adults who maintained a body mass index <23 kg/m2.Data Collection and Analysis: Baseline data on TPA and psychological factors were collected and T2DM incidence was assessed for 10 years. For analysis, a multivariable Cox proportional hazards regression model was used.Results: TPA was inversely associated with T2DM risk and this association was more pronounced in participants who were depressed or distressed; the top TPA quartile exhibited significant reductions in T2DM risk of 66% (95% confidence interval [CI]: 0.15, 0.78) and 65% (95% CI: 0.14, 0.88) among participants who reported depressed mood and those who perceived high distress, respectively, compared with the bottom TPA quartile.Conclusions: The current study demonstrated the preventive effects of physical activity on T2DM in lean adults through its interaction with psychological factors.

Modifiable Risk Factors for Prevention in Dupuytren Disease: A UK Biobank Case-Control Study

BACKGROUND

Dupuytren disease is associated with significant comorbidity and mortality, and it has no existing prevention strategies. It is unclear which modifiable risk factors are most amenable for prevention. This study aimed to determine the strength of modifiable risk factors for Dupuytren disease, and to investigate associations with other diseases.

METHODS

Using UK Biobank data, this case-control study analyzed the association between phenotypic variables and Dupuytren disease through multivariable logistic regression. Exposures assessed were age, sex, body mass index, waist-to-hip ratio, Townsend deprivation index, smoking status, alcohol intake, diabetes mellitus, hypertension, cancer, liver disease, respiratory disease, rheumatoid arthritis, epilepsy, psoriasis, and gout.

RESULTS

There were 4148 cases and 397,425 controls. Male sex (OR, 3.23; 95% CI, 2.90 to 3.60; P = 1.07 × 10 -100 ), increasing age (OR, 1.08; 95% CI, 1.07 to 1.08; P = 6.78 × 10 -167 ), material deprivation (OR, 1.01; 95% CI, 1.00 to 1.02; P = 0.0305), high-density lipoprotein cholesterol (OR, 1.76; 95% CI, 1.58 to 1.96; P = 3.35 × 10 -24 ), smoking exposure, and alcohol intake were all associated with increased odds of Dupuytren disease. With increasing obesity class, there was approximately 25% decreased odds (OR, 0.774; 95% CI, 0.734 to 0.816; P = 4.71 × 10 -21 ). Diabetes with microvascular or end-organ complications was associated with more than 2.5 times increased odds of Dupuytren disease (OR, 2.59; 95% CI, 1.92 to 3.44; P = 1.92 × 10 -10 ). Within this group, increasing hemoglobin A1c values by 10 mmol/mol, or 0.9%, increased the odds by 31% (OR, 1.31; 95% CI, 1.13 to 1.51; P = 2.19 × 10 -4 ).

CONCLUSION

Diabetes and poor glycemic control are major risk factors for Dupuytren disease, which present an opportunity for prevention.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Trajectories of fasting glucose and glycated haemoglobin in obese and non-obese incident diabetes: Results from two large cohort studies

AIMS

Diabetes development mechanisms vary by weight status. We aimed to compare cardiometabolic risk and characterize fasting plasma glucose (FPG) and glycated haemoglobin (HbA1c) trajectories before diagnosing type 2 diabetes in individuals with/without obesity.

METHODS

Data from the China Health and Retirement Longitudinal Study (CHARLS) and English Longitudinal Study of Ageing (ELSA) were analysed. Participants without diabetes and with a body mass index of 18.5-40 kg/m2 at baseline were included. Incident diabetes was ascertained by self-reported physician diagnosis and/or antidiabetic drug use, FPG ≥126 mg/dl and/or HbA1c ≥6.5%. The difference in the FPG/HbA1c trajectory before the diabetes diagnosis in participants with/without obesity was examined using mixed-effects models.

RESULTS

Among 11 925 eligible participants, 1361 incident diabetes cases (mean age: 61.4 years; male: 46.2%) were identified within 15 years of follow-up. Obese diabetes showed higher levels of diastolic blood pressure and C-reactive protein at diagnosis than non-obese diabetes. Mixed-effects models indicated the difference in the FPG trajectory before diagnosis by weight status was non-significant with a slope difference of 0.149 mg/dl (SE = 0.642, p = .816, CHARLS) and 0.013 mg/dl (SE = 0.013, p = .337, ELSA). However, obese diabetes showed a steep increase in HbA1c before diagnosis with a slope difference of 0.036% (SE = 0.016, p = .021) in the CHARLS and 0.032% (SE = 0.014, p = .027) in the ELSA, respectively. Sex-stratified analyses showed that the difference in HbA1c trajectory before the diabetes diagnosis by weight status was only significant in males.

CONCLUSIONS

Obese and non-obese diabetes developments may share a similar FPG but distinct HbA1c trajectory. Obese diabetes interventions require more attention to cardiometabolic risks. Moreover, studies addressing weight/sex-related differences in diabetes aetiologies and treatments are warranted.

GLUT4 degradation by GLUTFOURINH® in mice resembles moderate-obese diabetes of human with hyperglycemia and low lipid accumulation

BACKGROUNDS AND AIMS

Type 2 diabetes mellitus (T2D) is a chronic disease characterized by insulin resistance and hyperglycemia. To investigate T2D, genetic and chemical induced hyper-obese rodent models have been experimentally developed. However, establishment of moderate-obese diabetes model will confer diverse opportunities for translational studies. In this study, we found the chemical, GLUTFOURINH® (GFI), induces post-translational degradation of glucose transporter 4 (GLUT4). We aimed to establish novel diabetic model by using GFI.

METHODS AND RESULTS

Low plasma membrane GLUT4 (pmGLUT4) levels by GFI resulted in reduction of intracellular glucose uptake and TG, and increase of intracellular FFA in A204 cells. Likewise, GFI treatment decreased intracellular TG and increased intracellular FFA levels in Hep3B and 3T3-L1 cells. Mice were administered with GFI (16 mg/kg) for short-term (3-day) and long-term (28- and 31-day) to compared with vehicle injection, HFD model, and T2D model, respectively. Short-term and long-term GFI treatments induced hyperglycemia and hyperinsulinemia with low pmGLUT4 levels. Compared to HFD model, long-term GFI with HFD reduced adipose weight and intracellular TG accumulation, but increased plasma FFA. GFI treatment resulted in insulin resistance by showing low QUICKI and high HOMA-IR values, and low insulin response during insulin tolerance test. Additionally, low pmGLUT4 by GFI heightened hyperglycemia, hyperinsulinemia, and insulin resistance compared to T2D model.

CONCLUSIONS

In summary, we report GLUT4 degradation by novel chemical (GFI) induces moderate-obese diabetes representing hyperglycemia, insulin resistance and low intracellular lipid accumulation. The GLUT4 degradation by GFI has translational value for studying diseases related to moderate-obese diabetes.

A short review on the features of the non-obese diabetic Goto-Kakizaki rat intestine

The Goto-Kakizaki (GK) rat is a non-obese experimental model of type 2 diabetes mellitus (T2DM) that allows researchers to monitor diabetes-induced changes without jeopardizing the effects of obesity. This rat strain exhibits notable gastrointestinal features associated with T2DM, such as marked alterations in intestinal morphology, reduced intestinal motility, slow transit, and modified microbiota compared to Wistar rats. The primary treatments for diabetic patients include administration of hypoglycemic agents and insulin, and lifestyle changes. Emerging procedures, including alternative therapies, metabolic surgeries, and modulation of the intestinal microbiota composition, have been shown to improve the diabetic state of GK rats. This review describes the morpho-physiological diabetic-associated features of the gastrointestinal tract (GIT) of GK rats. We also describe promising strategies, e.g., metabolic surgery and modulation of gut microbiota composition, used to target the GIT of this animal model to improve the diabetic state.

Risk Factor Analysis for Type 2 Diabetes Patients About Hypoglycemia Using Continuous Glucose Monitoring: Results from a Prospective Observational Study

Introduction: To determine the relationship between hypoglycemia and glucose variability in outpatients with type 2 diabetes mellitus (T2DM). Materials and Methods: The study participants were 999 outpatients with T2DM who used the FreeStyle Libre Pro for continuous glucose monitoring (FLP-CGM). Hypoglycemia was defined as glucose level of <3.0 mM, and the frequency of episodes and duration of hypoglycemia were evaluated by comparing patients who did or did not achieve time-below-range <3.0 mM (TBR^<3.0) of <1% of the time. The association of TBR^<3.0 and long% coefficient of variation (%CV) with medications used was examined using multivariate analysis with a proportional odds model. Results: The average TBR^<3.0 was 0.33% (4.75 min). The TBR^<3.0 >1% group comprised 71/999 patients. Patients of the TBR^<3.0 >1% group had lower body mass index, longer disease duration, and poorer renal function. For the TBR^<3.0 >1% group, the predicted cutoff values were 7.19 mM average glucose (AG), and 30.30% for %CV. When AG <7.19 mM and %CV >30.30% were considered as hypoglycemic risk factors, the frequency and duration of hypoglycemia increased as the risk factor values increased. In multivariate analysis, sulfonylurea (SU) use, insulin use, and low blood glucose index correlated significantly with increased length of TBR^<3.0 and %CV, even after adjustment for concomitant diabetes medications. Conclusion: In T2DM, maintaining TBR^<3.0 <1% requires to keep AG >7.2 mM and %CV <30%, in addition to comprehensive management of CGM metrics. Since SU and insulin use is associated with prolonged TBR^<3.0 and increased %CV, their doses should be adjusted to avoid excessive fall in AG and raising %CV.

Understanding the pathogenesis of lean non-autoimmune diabetes in an African population with newly diagnosed diabetes

AIMS/HYPOTHESIS

Apparent type 2 diabetes is increasingly reported in lean adult individuals in sub-Saharan Africa. However, studies undertaking robust clinical and metabolic characterisation of lean individuals with new-onset type 2 diabetes are limited in this population. This cross-sectional study aimed to perform a detailed clinical and metabolic characterisation of newly diagnosed adult patients with diabetes in Uganda, in order to compare features between lean and non-lean individuals.

METHODS

Socio-demographic, clinical, biophysical and metabolic (including oral glucose tolerance test) data were collected on 568 adult patients with newly diagnosed diabetes. Participants were screened for islet autoantibodies to exclude those with autoimmune diabetes. The remaining participants (with type 2 diabetes) were then classified as lean (BMI <25 kg/m2) or non-lean (BMI ≥25 kg/m2), and their socio-demographic, clinical, biophysical and metabolic characteristics were compared.

RESULTS

Thirty-four participants (6.4%) were excluded from analyses because they were positive for pancreatic autoantibodies, and a further 34 participants because they had incomplete data. For the remaining 500 participants, the median (IQR) age, BMI and HbA1c were 48 years (39-58), 27.5 kg/m2 (23.6-31.4) and 90 mmol/mol (61-113) (10.3% [7.7-12.5]), respectively, with a female predominance (approximately 57%). Of the 500 participants, 160 (32%) and 340 (68%) were lean and non-lean, respectively. Compared with non-lean participants, lean participants were mainly male (60.6% vs 35.3%, p<0.001) and had lower visceral adiposity level (5 [4-7] vs 11 [9-13], p<0.001) and features of the metabolic syndrome (uric acid, 246.5 [205.0-290.6] vs 289 [234-347] μmol/l, p<0.001; leptin, 660.9 [174.5-1993.1] vs 3988.0 [1336.0-6595.0] pg/ml, p<0.001). In addition, they displayed markedly reduced markers of beta cell function (oral insulinogenic index 0.8 [0.3-2.5] vs 1.6 [0.6-4.6] pmol/mmol; 120 min serum C-peptide 0.70 [0.33-1.36] vs 1.02 [0.60-1.66] nmol/l, p<0.001).

CONCLUSIONS/INTERPRETATION

Approximately one-third of participants with incident adult-onset non-autoimmune diabetes had BMI <25 kg/m2. Diabetes in these lean individuals was more common in men, and predominantly associated with reduced pancreatic secretory function rather than insulin resistance. The underlying pathological mechanisms are unclear, but this is likely to have important management implications.

Metformin's Mechanism of Action Is Stimulation of the Biosynthesis of the Natural Cyclic AMP Antagonist Prostaglandylinositol Cyclic Phosphate (Cyclic PIP)

Metformin is the leading drug for treating type 2 diabetics, but the mechanism of action of metformin, despite some suggested mechanisms such as the activation of the AMP-kinase, is largely unknown. Among its many positive effects are the reduction of blood glucose levels, the inhibition of cyclic AMP synthesis, gluconeogenesis and an increase in sensitivity to insulin. Recent studies have described the natural antagonist of cyclic AMP, prostaglandylinositol cyclic phosphate. Synthesis of cyclic PIP is stimulated in all organs by hormones such as insulin and also by drugs such as metformin. Its primary action is to trigger the dephosphorylation of proteins/enzymes, phosphorylated on serine/threonine residues. Cyclic PIP triggers many of the regulations requested by insulin. The parallels between the beneficial effects of metformin and the regulations triggered by cyclic PIP suggest that the mechanism of action of this key drug may well be explained by its stimulation of the synthesis of cyclic PIP.

Fertility outcomes in women with pre-existing type 2 diabetes-a prospective cohort study

OBJECTIVE

To study childbirth and the risk of miscarriage and infertility among women who have received a diagnosis of type 2 diabetes before the start of their reproductive journey.

DESIGN

Register-based cohort study using the Skåne Healthcare Register SETTING: All healthcare visits for the whole population of the southernmost region in Sweden over the past 20 years PATIENT(S): All women who were aged 18-45 years between January 1, 1998 and December 31, 2019 and who received a clinical diagnosis of type 2 diabetes before their first childbirth, miscarriage, or infertility diagnosis (n = 230) were compared with a healthcare-seeking population of women without any type of diabetes, matched for calendar year and age (n = 179,434).

INTERVENTION(S)

None MAIN OUTCOME MEASURE(S): Childbirth, miscarriage, and infertility diagnosis RESULT(S): The birthrate was lower among women with type 2 diabetes (62.6% vs. 83.8%), and they were less likely to give birth (crude risk ratio [RR] = 0.73, 95% confidence interval [CI]: 0.66-0.81). They had a higher risk of experiencing a miscarriage (RR = 1.88, 95% CI: 1.50-2.36). The risk of infertility was increased (RR = 3.44, 95% CI: 2.88-4.10) as was the risk of having infertility and not giving birth (RR = 4.47, 95% CI: 3.44-5.82). All results remained the same after adjustment for polycystic ovary syndrome and obesity.

CONCLUSION(S)

Women with type 2 diabetes with onset before their reproductive journey were more often childless compared with women without diabetes and had a higher risk of experiencing both miscarriage and infertility. This patient group may be in need of targeted information regarding potential fertility issues as part of their clinical treatment.

Corrination of a GLP-1 Receptor Agonist for Glycemic Control without Emesis

Glucagon-like peptide-1 receptor (GLP-1R) agonists used to treat type 2 diabetes mellitus often produce nausea, vomiting, and in some patients, undesired anorexia. Notably, these behavioral effects are caused by direct central GLP-1R activation. Herein, we describe the creation of a GLP-1R agonist conjugate with modified brain penetrance that enhances GLP-1R-mediated glycemic control without inducing vomiting. Covalent attachment of the GLP-1R agonist exendin-4 (Ex4) to dicyanocobinamide (Cbi), a corrin ring containing precursor of vitamin B12, produces a "corrinated" Ex4 construct (Cbi-Ex4). Data collected in the musk shrew (Suncus murinus), an emetic mammal, reveal beneficial effects of Cbi-Ex4 relative to Ex4, as evidenced by improvements in glycemic responses in glucose tolerance tests and a profound reduction of emetic events. Our findings highlight the potential for clinical use of Cbi-Ex4 for millions of patients seeking improved glycemic control without common side effects (e.g., emesis) characteristic of current GLP-1 therapeutics.

Safety and effectiveness of tofogliflozin in Japanese patients with type 2 diabetes mellitus treated in real-world clinical practice: Results of a 36-month post-marketing surveillance study (J-STEP/LT)

AIMS/INTRODUCTION

Tofogliflozin is a sodium-glucose cotransporter 2 (SGLT2) inhibitor that lowers plasma glucose levels by enhancing urinary glucose excretion. After its approval in Japan in 2014 for the treatment of type 2 diabetes mellitus, we carried out a 3-year prospective observational post-marketing surveillance study in Japanese patients (Japanese Study of Tofogliflozin with Type 2 Diabetes Mellitus Patients/Long Term [J-STEP/LT]).

MATERIALS AND METHODS

This surveillance was carried out between September 2014 and February 2019, and recorded safety in terms of adverse drug reactions (ADRs) and ADRs of special interest, and effectiveness in terms of changes in glycated hemoglobin and bodyweight from baseline to last observation carried forward.

RESULTS

Of 6,897 patients with type 2 diabetes mellitus registered, 6,711 and 6,451 were analyzed for safety and effectiveness, respectively. ADRs were reported in 846 patients (12.61%), with serious ADRs in 101 patients (1.5%). ADRs of special interest included hypoglycemia (62 patients [0.9%]), polyuria/pollakiuria (90 [1.3%]), volume depletion-related disorders (135 [2.0%]), urinary tract infections (91 [1.4%]), genital infections (117 [1.7%]) and skin diseases (53 [0.8%]). One case of diabetic ketoacidosis was reported. The mean ± standard deviation changes from baseline to last observation carried forward in glycated hemoglobin and bodyweight were -0.68 ± 1.34% (n = 6,158, P < 0.0001) and -3.13 ± 4.67 kg (n = 5,213, P < 0.0001), respectively.

CONCLUSIONS

J-STEP/LT, a 3-year, prospective, observational, post-marketing study in Japan, found no unprecedented ADRs, and consistent reductions from baseline in glycated hemoglobin and bodyweight over the observation period. The present results provide further evidence regarding the safety and tolerability of tofogliflozin in Japanese patients with type 2 diabetes mellitus.

The salivary microbiota of Thai adults with metabolic disorders and association with diet

OBJECTIVE

This study aimed to investigate abundance of specific bacterial taxa in the saliva of 105 Thai adults with different BMI (lean, overweight, and obese) and T2DM subjects using qPCR targeting the 16S rRNA gene of various bacteria taxa.

DESIGN

We employed qPCR targeting 16S rRNA genes to explore the bacterial profiles and abundances in the saliva of Thai adult subjects with different BMI and T2DM. Multivariate statistical analyses (multiple factor analysis (MFA) and sparse Partial Least Squares Discriminant Analysis (sPLS-DA) were performed to assess the associations of salivary bacteria with diet, blood profile, gender, age, and use of antibiotics.

RESULTS

We found that abundance profiles of the examined salivary bacteria were similar across the four groups. When diet, blood profile, and gender, age, and use of antibiotics were considered, significant differences were noted between subgroups. A positive correlation was also found between consumption of carbonate soft drinks and Bacteroidetes, Gamma-proteobacteria, Veillonella, Fusobacterium and Fusobacterium nucleatum.

CONCLUSIONS

This is the first study demonstrating the relative abundance of salivary bacteria in adult Thai subjects with different levels of BMI and T2DM. Regardless of the similar pattern of bacterial profiles across groups, sPLS-DA analysis highlighted the influence of host variables (gender, age, and use of antibiotics) on the abundance of salivary microbiota. Our findings pave the way for further hypothesis testing to gain insight into the association between host factors and salivary microbiome.

Disentangling the heterogeneity of adulthood-onset non-autoimmune diabetes: a little closer but lot more to do

Diabetes diagnosed in adults is a highly heterogeneous disorder. It mostly consists of what is referred to as type 2 diabetes but also comprises other entities (i.e. different diseases), including latent autoimmune diabetes, late onset forms of monogenic diabetes and familial diabetes of the adulthood, which has recently been the source of new diabetogenes discovery. Notably, type 2 diabetes is itself heterogeneous as it includes subtypes with onset at the extremes of age and/or weight distributions characterized by different degree of hyperglycemia and cardiovascular risk as compared to common forms of type 2 diabetes occurring in middle-aged, overweight/obese individuals. Understanding whether these are different presentations of one, highly heterogeneous disease or separate nosological entities with different clinical trajectories and requiring different treatments is essential to effectively pursue the path of precision medicine.

Associations of alcohol consumption and physical activity with lean type 2 diabetes mellitus among Korean adults: A prospective cohort study

Data on the association between alcohol consumption and the risk of type 2 diabetes mellitus (T2DM) have accumulated, but little has been reported about this association in terms of lean T2DM. The present study analyzed 10-year longitudinal data to investigate the association between alcohol consumption and T2DM risk among lean individuals. This prospective study included 2,366 male and female Koreans aged 40–69 years who were free of DM and had a body mass index (BMI) <23 kg/m² during the baseline period between 2001 and 2012. Information on alcohol consumption, BMI, and incident cases of T2DM were identified by interviews and health examinations. To analyze the association between alcohol consumption and T2DM risk, Cox proportional hazard regression analysis was used. Alcohol drinkers consuming at least 16 g/day of alcohol (2 units/day) who maintained a BMI <23 kg/m² over 10 years had a significantly higher T2DM risk even after controlling for BMI and potential risk factors. Compared with lifetime abstainers, multivariate hazard ratios (HR) [95% confidence interval] of T2DM were 1.74 [1.02, 2.95] for 16–30 g/day, 2.09 [1.16, 3.77] for 31–60 g/day, and 1.94 [1.07, 3.51] for >60g/day among alcohol drinkers. No protective effect of moderate alcohol consumption <16 g/day on T2DM risk was observed. Age, parental history of DM, and physical inactivity were also significant risk factors for lean T2DM. Alcohol consumption of at least 2 units/day increased T2DM risk among lean individuals. Abstaining from alcohol and physical activity may be beneficial for the prevention of lean T2DM.

Complex interaction of fasting glucose, body mass index, age and sex on all-cause mortality: a cohort study in 15 million Korean adults

AIMS/HYPOTHESIS

The aim of this work was to examine whether synergistic associations with mortality exist for BMI and fasting blood glucose (FBG) and to identify FBG-BMI combined subgroups with higher mortality according to sex and age.

METHODS

A total of 15,149,275 Korean adults participated in health examinations during 2003-2006 and were followed up until December 2018. Mortality HRs of 40 FBG-BMI combined groups were assessed by Cox proportional hazards models.

RESULTS

During a mean 13.7 years of follow-up, 1,213,401 individuals died. A J-shaped association was seen between FBG and all-cause mortality for all BMI categories. Those with BMI <20 kg/m² had the highest mortality for any given FBG level, followed by those with BMI 20-22.4 kg/m². The detrimental effect of elevated FBG was greater among leaner individuals than more corpulent individuals. Moreover, the synergistic adverse effects of hyperglycaemia and leanness was stronger in younger adults than in older adults. Compared with the reference group (overweight with normoglycaemia), age- and sex-adjusted HRs of the leanest with normoglycaemia (BMI <20 kg/m² and FBG 4.4-5.2 mmol/l), overweight with diabetes (BMI 25-27.4 kg/m² and FBG ≥10.0 mmol/l) and leanest with diabetes (BMI <20 kg/m² and FBG ≥10.0 mmol/l) were 1.29, 2.59 and 11.18, respectively, in those aged 18-44 years and 1.56, 1.72 and 2.87, respectively, in those aged 75-99 years. The identification of BMI-FBG subgroups associated with higher mortality was not straightforward, illustrated by the group with FBG 6.1-6.9 mmol/l and BMI 20-22.4 kg/m² having a similar or higher mortality compared with the group with FBG 7.0-9.9 mmol/l and BMI ≥22.5 kg/m². In women aged <45 years with FBG <6.9 mmol/l, those with BMI ≥27.5 kg/m² had the highest mortality, whereas individuals with BMI <20 kg/m² had the highest mortality for each given FBG level in other age and sex groups.

CONCLUSIONS/INTERPRETATION

Leanness and hyperglycaemia interact together to increase mortality in a supra-multiplicative manner, especially in younger adults; the interactions of BMI, FBG, sex and age with mortality are complex. Graphical abstract.

The Pathophysiology of Type 2 Diabetes Mellitus in Non-obese Individuals: An Overview of the Current Understanding

The pandemic of type 2 diabetes mellitus (T2DM) has been largely attributed to the increasing prevalence of worldwide obesity at a geometric rate. However, the number of non-obese patients with T2DM is also on the rise, and it is as high as 60-80% in some Asian countries. These non-obese individuals have certain peculiarities and have a higher mortality rate compared with obese individuals. The pathophysiology of T2DM in non-obese individuals remains poorly understood, and this has an impact on defining its management. This review discusses the current understanding of the pathophysiology of T2DM in non-obese individuals. The definition of T2DM in non-obese individuals remains controversial because of the limited clinical measurements, and the current definition of obesity using body mass index (BMI) is not very helpful as these individuals have BMIs of <25K g/m3, which is considered normal. Many authors have argued that the so-called non-obese people are actually metabolically obese; however, in terms of the measurements clinically available, they are non-obese. The simplistic understanding of the mechanism of the pathophysiology sees it in terms of the balance between insulin secretion and insulin resistance. The pathogenesis of insulin resistance in a lean patient has been proven to be the same as what is seen in an obese individual, but most studies confirm more severe functional insulin secretory defects in lean individuals compared to the obese phenotype. The mechanism underlying this form of T2DM is still poorly defined, and more research is required to understand the mechanism of sarcopenic obesity, which some studies have revealed.

Prevalence and determinants of type 2 diabetes among lean African migrants and non-migrants: the RODAM study

Background

Exposure to adverse conditions earlier in life-course can predispose to type 2 diabetes in adulthood, irrespective of body mass index (BMI). However, the burden of type 2 diabetes in lean Africans is not well understood despite higher exposure to adverse early life conditions. Mirroring ongoing epidemiological transition, we assessed the burden and determinants of type 2 diabetes in a homogenous group of lean Ghanaians residing in rural and urban Ghana, and as migrants in Europe.

Methods

Baseline data from 2179 RODAM study participants with BMI<25kg/m² (25-70 years) were analyzed. Prevalence and determinants of type 2 diabetes were estimated using logistic regression analysis. Adjustments were made for socio-demographic and lifestyle factors, use of anti-diabetic medication and optimal blood glucose control.

Results

Prevalence of type 2 diabetes in rural, urban and migrant lean participants were 3.5%, 8.9% and 7.5% respectively, representing 55.4%, 35.6%, 13.2% of all participants with type 2 diabetes. Compared with lean rural participants, the odds of type 2 diabetes were higher in lean urban participants (adjusted OR = 8.81, 95% CI = 6.56-11.06), followed by migrants (5.27, 95% CI = 3.51-6.91). Irrespective of site, determinants of type 2 diabetes in lean participants include; presence of hypertension, physical inactivity, hypercholesterolemia and age (>45 years).

Conclusions

Our study shows a high prevalence of type 2 diabetes among lean African populations in different geographical settings. Future studies are needed in-order to examine how contextual differences are related to the pathophysiology of type 2 diabetes in lean individuals.

Diabetes: a metabolic and reproductive disorder in women

Reproductive dysfunction is a common but little studied complication of diabetes. The spectrum of reproductive health problems in diabetes is broad, and encompasses delayed puberty and menarche, menstrual cycle abnormalities, subfertility, adverse pregnancy outcomes, and potentially early menopause. Depending on the age at diagnosis of diabetes, reproductive problems can manifest early on in puberty, emerge later when fertility is desired, or occur during the climacteric period. Historically, women with type 1 diabetes have frequently had amenorrhoea and infertility, due to central hypogonadism. With the intensification of insulin therapy and improved metabolic control, these problems have declined, but do persist. Additional reproductive implications of contemporary diabetes management are now emerging, including polycystic ovary syndrome and hyperandrogenism, which are underpinned by insulin action on the ovary. The sharp rise in type 2 diabetes incidence in youth suggests that more women of reproductive age will encounter diabetes-related reproductive problems in their lifetimes. With an ever increasing number of young women living with diabetes, clinicians need to be aware of and equipped for the challenges of navigating reproductive health concerns across the lifespan.

Insulin Resistance and β-Cell Function of Lean versus Overweight or Obese Filipino Patients with Newly Diagnosed Type 2 Diabetes Mellitus

Objectives

To compare the level of insulin resistance and β-cell function between lean and overweight/obese Filipino patients with newly diagnosed type 2 diabetes mellitus (T2DM).

Methodology

This was a cross-sectional analytical study including newly diagnosed T2DM Filipino patients from St. Luke’s Medical Center - Quezon City. The patients were classified as either lean or overweight/obese. Age, sex, smoking history, anthropometric measures and blood pressure were obtained. Insulin resistance and β-cell function were determined using the homeostasis model assessment (HOMA). The original model (HOMA1) and the updated model (HOMA2) were used.

Results

A total of 80 subjects were included. There were 40 subjects in each group. The overweight/obese subjects had significantly higher mean insulin resistance (HOMA1-IR 9.8±11.7, HOMA2-IR 3.0±2.0) compared to the lean group (HOMA1-IR 2.9±1.5, HOMA2-IR 1.3±0.5). This was consistent in both HOMA1 and HOMA2 (p-values=0.001 and <0.001, respectively). The mean β-cell function of the overweight/obese patients was significantly higher than the lean subjects when using HOMA1 (lean=57.8±35.5, overweight/obese=93.6±66.4, p-value=0.003), but not in HOMA2 (lean=57.6±30.5, overweight/obese=74.8±45.7, p-value=0.051). Overweight/obesity increased HOMA1-IR by 4.0 and HOMA1-B by 46.1 (p-values= 0.002 and <0.001, respectively). Through the use of HOMA2, overweight/obesity increased HOMA2-IR by 1.4 and HOMA2-B by 29.1 (p-values<0.001). Being overweight/obese was also associated with significantly higher odds for developing greater insulin resistance (HOMA1-IR adjOR = 5.6, 95%CI= 1.7-19.2, p-value=0.005; HOMA2-IR adjOR=10.9, 95%CI=3.4-34.9, p-value<0.001) and lower odds for a decreased β-cell function (HOMA1-B adjOR = 0.2, 95%CI = 0.05-0.9, p-value=0.033; HOMA2-B adjOR=0.2, 95%CI=0.04-0.9, p-value=0.043) compared to being lean.

Conclusion

Newly diagnosed overweight/obese T2DM had higher mean insulin resistance and β-cell function compared to lean T2DM. Overweight/obesity was also associated with higher odds of developing insulin resistance and lower odds for a decreased β-cell function compared to being lean. The overweight/obese T2DM group also had worse metabolic profile manifested by higher FPG, HbA1c, SGPT and blood pressures compared to the lean T2DM group.

Primary Cilium, An Unsung Hero in Maintaining Functional β-cell Population

A primary challenge in type 2 diabetes (T2D) is the preservation of a functional population of β-cells, which play a central role in regulating blood glucose levels. Two congenital disorders, Bardet-Biedl syndrome (BBS) and Alström syndrome (ALMS), can serve as useful models to understand how β-cells are normally produced and regenerated. Both are characterized by obesity, loss of β-cells, and defects in primary cilia - the sensory center of cells. Primary cilia are cellular protrusions present in almost every vertebrate cell. This antenna-like organelle plays a crucial role in regulating several signaling pathways that direct proper development, proliferation, and homeostasis. Mutations in genes expressing ciliary proteins or proteins present at or near the base of the cilium lead to disorders, collectively called ciliopathies. BBS and Alström syndrome are such disorders. Though both BBS and Alström patients are obese, their childhood diabetes rates are vastly different, suggesting distinct pathogenesis underlying these two ciliopathies. Clinical studies suggest that BBS patients are protected against early onset diabetes by sustained or enhanced β-cell function. In contrast, Alström patients are more prone to develop diabetes. They have hyperinsulinemia, yet their β-cells fail to sense glucose and to regulate insulin secretion accordingly. These data suggest a potential role for primary cilia in maintaining a functional β-cell population and that defects in cilia or in ciliary proteins impair development and function of β-cells. Identifying the respective roles of primary cilia and ciliary proteins, such as BBS and ALMS1 may shed light on β-cell biology and uncover potentially novel targets for diabetes therapy.

Sex Dependent Dysregulation of Hepatic Glucose Production in Lean Type 2 Diabetic Rats

We have characterized a lean type 2 diabetic rat model by gestational low protein programming. We aimed to identify if the regulation of hepatic glucose production (HGP) via gluconeogenesis and glycogenolysis is affected and if there are any sex differences. Fasting (6-7 months old) type 2 diabetic rats received 2H2O followed by a primed constant rate infusion of [6,6-2H2] glucose. Blood samples were drawn during steady states after 4 h of fasting and following a euglycemic hyperinsulinemic clamp. HGP and the fraction of glucose derived from gluconeogenesis under fasting and euglycemic states were measured from steady state glucose enrichments after the infusion of [6,6-2H2]glucose and 2H2O tracers. Glycogenolysis was determined by calculating the difference between total HGP and gluconeogenesis rates. Hepatic gene expression of enzymes involved in HGP were quantified using qPCR. HGP rates was similar during fasting in both groups and sexes. However, under simulated fed condition, HGP rate was suppressed in controls but not in type 2 diabetic rats. They also showed inefficient HGP suppression in a simulated fed state. Differential analysis showed that suppression of both gluconeogenesis and glycogenolysis under simulated fed state was affected in these low protein programmed type 2 diabetic rats. These effects were greater in females when compared to males. Further, key genes involved in these processes like G6Pase, Pepck, pyruvate carboxylase, and glycogen phosphorylase in liver were dysregulated. Our data shows impaired suppression of HGP via gluconeogenesis and glycogenolysis in type 2 diabetic rats with greater effects on females.

Regional differences in type 2 diabetes treatment and outcomes in Germany-An analysis of the German DPV and DIVE registries

AIMS

On the basis of the Diabetes Versorgungs-Evaluation (DIVE) and Diabetes-Patienten-Verlaufsdokumentation (DPV) datasets, we aimed to explore the impact of differences in treatment modalities on outcomes in Germany and put these into a global context.

METHODS

The 2014 to 2016 DIVE and DPV databases were combined, and a total of 127 838 patients 18 years and older was analysed with respect to demographics, cardiovascular risk factors, comorbidities, treatments, and outcomes, separately for each German state. Estimates were expressed as adjusted least squares means together with 95% confidence intervals.

RESULTS

Saarland dataset recorded the lowest mean HbA_1c (6.7%; 6.6%-6.8%; 50 mmol/mol, 49-51 mmol/mol), Saxony-Anhalt showed the highest (8.3%; 8.2%-8.3%; 67 mmol/mol, 66-67 mmol/mol). The highest percentage of hypoglycaemic events was reported in Mecklenburg-West Pomerania (MWP) (4.7%; 3.9%-5.7%), the lowest in Thuringia (0.9%; 0.2%-3.4%). Metformin and sulfonylurea accounted for 36.4% to 53.3% of anti-diabetic treatments across states; other antihyperglycaemic drugs such as DPP-4 inhibitors, SGLT2 inhibitors, and GLP-1 analogues were used most often in MWP (40.0%; 37.8%-42.1%) and least in Rhineland-Palatinate (13.6%; 13.0%-14.2%). Treatment with insulin (alone or in combination) was reported most often in MWP (78.2%; 76.4%-80.0%) and least in Thuringia (26.0%; 20.1%-32.9%).

CONCLUSIONS

Federal states in Germany are heterogeneous concerning diabetes treatment and associated outcomes. These data should stimulate further discussion about how optimal diabetes care can be implemented in all areas of Germany, to achieve good treatment outcomes in all federal states.

A vitamin B12 conjugate of exendin-4 improves glucose tolerance without associated nausea or hypophagia in rodents

AIMS

While pharmacological glucagon-like peptide-1 receptor (GLP-1R) agonists are FDA-approved for treating type 2 diabetes mellitus (T2DM) and obesity, a major side effect is nausea/malaise. We recently developed a conjugate of vitamin B12 (B12) bound to the GLP-1R agonist exendin-4 (Ex4), which displays enhanced proteolytic stability and retention of GLP-1R agonism. Here, we evaluate whether the conjugate (B12-Ex4) can improve glucose tolerance without producing anorexia and malaise.

MATERIALS AND METHODS

We evaluated the effects of systemic B12-Ex4 and unconjugated Ex4 on food intake and body weight change, oral glucose tolerance and nausea/malaise in male rats, and on intraperitoneal glucose tolerance in mice. To evaluate whether differences in the profile of effects of B12-Ex4 vs unconjugated Ex4 are the result of altered CNS penetrance, rats received systemic injections of fluorescein-Ex4 (Flex), Cy5-B12 or Cy5-B12-Ex4 and brain penetrance was evaluated using confocal microscopy. Uptake of systemically administered Cy5-B12-Ex4 in insulin-containing pancreatic beta cells was also examined.

RESULTS

B12-Ex4 conjugate improves glucose tolerance, but does not elicit the malaise and anorexia produced by unconjugated Ex4. While Flex robustly penetrates into the brain (dorsal vagal complex, paraventricular hypothalamus), Cy5-B12 and Cy5-B12-Ex4 fluorescence were not observed centrally, supporting an absence of CNS penetrance, in line with observed reduction in CNS-associated Ex4 side effects. Cy5-B12-Ex4 colocalizes with insulin in the pancreas, suggesting direct pancreatic action as a potential mechanism underlying the hypoglycaemic effects of B12-Ex4.

CONCLUSION

These novel findings highlight the potential clinical utility of B12-Ex4 conjugates as possible future T2DM therapeutics with reduced incidence of adverse effects.