Pathophysiology-based phenotyping in type 2 diabetes: A clinical classification tool

Amylin: From Mode of Action to Future Clinical Potential in Diabetes and Obesity

Precision diabetology is increasingly becoming diabetes phenotype-driven, whereby the specific hormonal imbalances involved are taken into consideration. Concomitantly, body weight-favorable therapeutic approaches are being dictated by the obesity pandemic, which extends to all diabetes subpopulations. Amylin, an anorexic neuroendocrine hormone co-secreted with insulin, is deficient in individuals with diabetes and plays an important role in postprandial glucose homeostasis, with additional potential cardiovascular and neuroprotective functions. Its actions include suppressing glucagon secretion, delaying gastric emptying, increasing energy expenditure and promoting satiety. While amylin holds promise as a therapeutic agent, its translation into clinical practice is hampered by complex receptor biology, the limitations of animal models, its amyloidogenic properties and pharmacokinetic challenges. In individuals with advanced β-cell dysfunction, supplementing insulin therapy with pramlintide, the first and currently only approved injectable short-acting selective analog of amylin, has demonstrated efficacy in enhancing both postprandial and overall glycemic control in both type 2 diabetes (T2D) and type 1 diabetes (T1D) without increasing the risk of hypoglycemia or weight gain. Current research focuses on several key strategies, from enhancing amylin stability by attaching polyethylene glycol or carbohydrate molecules to amylin, to developing oral amylin formulations to improve patients' convenience, as well as developing various combination therapies to enhance weight loss and glucose regulation by targeting multiple receptors in metabolic pathways. The novel synergistically acting glucagon-like peptide-1 (GLP-1) receptor agonist combined with the amylin agonist, CagriSema, shows promising results in both glucose regulation and weight management. As such, amylin agonists (combined with other members of the incretin class) could represent the elusive drug candidate to address the multi-hormonal dysregulations of diabetes subtypes and qualify as a precision medicine approach that surpasses the long overdue division into T1DM and T2DM. Further development of amylin-based therapies or delivery systems is crucial to fully unlock the therapeutic potential of this intriguing hormone.Graphical abstract available for this article.

Educational inequalities in clinical presentation and pharmacological treatment of early type 2 diabetes: A Danish prevalence study

AIMS

To examine how educational attainment impacts clinical presentation and pharmacological treatment at type 2 diabetes (T2D) diagnosis.

METHODS

Cross-sectional analysis of 10,020 individuals with recently diagnosed T2D enrolled in the Danish prospective DD2 cohort. Sex- and age-adjusted prevalence ratios (aPRs) for detailed clinical characteristics and pharmacotherapy were computed.

RESULTS

In total, 31 % had low, 50 % had moderate, and 19 % had high educational level. Individuals with low rather than high educational level were more often obese (58 % vs 49 %, aPR 1.20 [95 % CI 1.14-1.28]); had less healthy lifestyles (current smokers: 22 % vs 15 %, aPR 1.53 [1.32-1.76]); sedentary activity level: 21 % vs 15 %, aPR 1.36 [1.20-1.55]); and had more often cardiovascular (23 % vs. 17 %, PR 1.30 [1.16-1.46]) and microvascular complications (16 % vs 13 %, aPR 1.18 [1.02-1.35]). Low education associated with higher triglycerides, more insulin resistance, and poorer kidney function, whereas HbA1c, blood pressure, and LDL cholesterol were identical. The use of medications with cardiovascular benefits and newer organ-protective diabetes medications was similar to, or higher than, that in individuals with high education.

CONCLUSIONS

Awareness of the impact of social and educational determinants on T2D presentation at diagnosis is essential to improve treatment and prognosis.

Association of fibrinogen αE, fibrinogen γ', and sialylated fibrinogen with development of ischemic stroke in patients with recently diagnosed type 2 diabetes

BACKGROUND

Stroke is a major cause of death globally, especially in type 2 diabetes (T2D) patients. Fibrinogen is known to predict stroke risk, but fibrinogen is a highly variable protein and we hypothesized that fibrinogen variants can improve stroke prediction.

OBJECTIVES

We aimed to investigate the association of total fibrinogen and fibrinogen variants with risk of ischemic stroke in T2D patients.

METHODS

In a nested case-control study with a median follow-up of 4.1 years, we included 144 T2D patients with ischemic stroke (cases) and 144 matched T2D patients without ischemic stroke (controls). We measured total fibrinogen, absolute, and relative levels of 3 fibrinogen variants (fibrinogen αE, fibrinogen γ', and sialylated fibrinogen) and compared levels between cases and controls. We used logistic regression to determine the association with stroke risk.

RESULTS

Total fibrinogen and absolute levels of fibrinogen αE, fibrinogen γ', and sialylated fibrinogen were higher in stroke cases than controls. Absolute levels of fibrinogen positively associated with risk of stroke for total fibrinogen (highest vs lowest tertile; adjusted odds ratio (OR), 1.9 [95% CI, 0.9-4.2]), fibrinogen γ' (OR, 1.8 [0.8-3.8]), and sialylated fibrinogen (OR, 2.5 [1.1-5.8]). Relative levels of fibrinogen variants did not convincingly associate with stroke risk.

CONCLUSION

Patients with T2D who developed stroke had increased levels of total fibrinogen, fibrinogen αE, fibrinogen γ', and sialylated fibrinogen compared with T2D controls. Total fibrinogen and absolute, but not relative, levels of fibrinogen γ' and sialylated fibrinogen prospectively associated with a 2-fold increased risk of ischemic stroke.

Obesity and insulinopenic type 2 diabetes differentially impact, bone phenotype, bone marrow adipose tissue, and serum levels of the cathelicidin-related antimicrobial peptide in mice

Obesity is a risk factor of developing type 2 diabetes (T2D) and metabolic complications, through systemic inflammation and insulin resistance. It has also been associated with increased bone marrow adipocytes along with increased bone fragility and fracture risk. However, the differential effects of obesity and T2D on bone fragility remain unclear. The cathelicidin-related antimicrobial peptide (CRAMP) is a multifunctional modulator of the innate immunity that has emerged as biomarker of cardiometabolic diseases. The aims of this study were i) to assess the differential impact between hyperinsulinemic obesity versus insulinopenic T2D, on bone phenotype and bone marrow adipose tissue (BMAT), and ii) to analyse the link with CRAMP expression and its circulating levels in the context of obesity and T2D. We used C57BL/6 J male mice models of obesity induced by high-fat diet (HFD), and of insulinopenic T2D induced by streptozotocin (STZ) treatment combined with HFD, reflecting the metabolic heterogeneity of the diseases. As compared to low-fat diet (LFD) control group after 16 weeks of feeding, the HFD mice exhibit a significant weight gain, moderate hyperglycaemia, impaired glucose tolerance and insulin sensitivity, and significant increase in serum insulin levels. This hyperinsulinemic obesity led to decreased trabecular (Tb.Th) and cortical thickness (Ct.Th) in the tibia, associated with significant BMAT expansion, in addition to increased subcutaneaous (SCAT) and visceral adipose tissue (VAT). No changes were observed in the circulating levels of CRAMP peptide neither in other bone parameters. While, STZ treatment in HFD/STZ group induced a more severe hyperglycaemia, glucose intolerance and insulin resistance, and hypoinsulinemia. We also observed a negative effect on the expansion of both SCAT and VAT, as well as lower increase in BMAT as compared to HFD group. However, these mice with insulinopenic T2D exhibit early decrease in trabecular number (Tb.N) in proximal tibia, progressively from 8 to 16 weeks of protocol, and impaired femoral biomechanical stiffness. These alterations are also accompanied with decreased circulating levels of the CRAMP peptide in the HFD/STZ mice. The CRAMP mRNA levels decreased in VAT of both HFD and HFD/STZ groups. Overall, these results provide novel insights into the differential negative impact of obesity versus T2D on bone microenvironment, and suggest a link between hyperglycaemia-induced bone quality alterations during insulinopenia, and impaired regulation of the cathelicidin peptide of the innate immunity. Further investigations are needed to elucidate this relationship.

Elevated risk of infection in individuals with hyperinsulinaemic type 2 diabetes: a Danish 12 year cohort study

AIMS/HYPOTHESIS

A better understanding of the mechanisms underlying an elevated infection risk in individuals with type 2 diabetes is needed to guide risk stratification and prevention. We investigated the risk of infection in subgroups of individuals with type 2 diabetes according to indices of insulin sensitivity and beta cell function.

METHODS

We classified 7265 individuals with recently diagnosed type 2 diabetes (median duration 1.4 years, IQR 0.5-2.9 years) into hyperinsulinaemic (high beta cell function [HOMA 2-beta-cell function, HOMA2-B], low insulin sensitivity [HOMA 2-insulin sensitivity, HOMA2-S]), classical (low HOMA2-B, low HOMA2-S) and insulinopenic (low HOMA2-B, high HOMA2-S) type 2 diabetes. Individuals were followed until first hospital-treated infection or first prescription for an anti-infective agent (community-treated infection). We used Cox regression analysis to estimate HRs adjusted for age, sex, index year, diabetes duration and treatment, lifestyle behaviours and comorbidities.

RESULTS

Among study participants, 28% had hyperinsulinaemic, 63% had classical and 9% had insulinopenic type 2 diabetes. The 10 year risks of hospital-treated infections were 42.3%, 36.8% and 31.0% in the three subgroups, respectively. Compared with the insulinopenic subgroup, adjusted HRs for hospital-treated infections were elevated for hyperinsulinaemic (1.38 [95% CI 1.16, 1.65]) and classical type 2 diabetes (1.20 [95% CI 1.02, 1.42]). The 10 year risks of community-treated infections were high in all three subgroups at 91.6%, 90.1% and 88.3%, respectively, corresponding to adjusted HRs of 1.20 (95% CI 1.08, 1.33) for the hyperinsulinaemic and 1.10 (95% CI 1.00, 1.21) for the classical subgroup. Infection risk in the hyperinsulinaemic subgroup decreased substantially when further adjusted for abdominal obesity, metabolic derangements and low-grade inflammation.

CONCLUSIONS/INTERPRETATION

The risk of severe infections is clearly elevated in individuals with type 2 diabetes characterised by a higher degree of insulin resistance/hyperinsulinaemia.

Characterizing Circulating microRNA Signatures of Type 2 Diabetes Subtypes

Type 2 diabetes (T2D) is a heterogeneous disease influenced by both genetic and environmental factors. Recent studies suggest that T2D subtypes may exhibit distinct gene expression profiles. In this study, we aimed to identify T2D cluster-specific miRNA expression signatures for the previously reported five clinical subtypes that characterize the underlying pathophysiology of long-standing T2D: severe insulin-resistant diabetes (SIRD), severe insulin-deficient diabetes (SIDD), mild age-related diabetes (MARD), mild obesity-related diabetes (MOD), and mild early-onset diabetes (MEOD). We analyzed the circulating microRNAs (miRNAs) in 45 subjects representing the five T2D clusters and 7 non-T2D healthy controls by single-end small RNA sequencing. Bioinformatic analyses identified a total of 430 known circulating miRNAs and 13 previously unreported novel miRNAs. Of these, 71 were upregulated and 37 were downregulated in either controls or individual clusters. Each T2D subtype was associated with a specific dysregulated miRNA profile, distinct from that of healthy controls. Specifically, 3 upregulated miRNAs were unique to SIRD, 1 to MARD, 9 to MOD, and 18 to MEOD. Among the downregulated miRNAs, 11 were specific to SIRD, 9 to SIDD, 2 to MARD, and 1 to MEOD. Our study confirms the heterogeneity of T2D, represented by distinguishable subtypes both clinically and epigenetically and highlights the potential of miRNAs as markers for distinguishing the pathophysiology of T2D subtypes.

Clinical utility of novel diabetes subgroups in predicting vascular complications and mortality: up to 25 years of follow-up of the HUNT Study

INTRODUCTION

Cluster analysis has previously revealed five reproducible subgroups of diabetes, differing in risks of diabetic complications. We aimed to examine the clusters' predictive ability for vascular complications as compared with established risk factors in a general adult diabetes population.

RESEARCH DESIGN AND METHODS

Participants from the second (HUNT2, 1995-1997) and third (HUNT3, 2006-2008) surveys of the Norwegian population-based Trøndelag Health Study (HUNT Study) with adult-onset diabetes were included (n=1899). To identify diabetes subgroups, we used the same variables (age at diagnosis, body mass index, HbA1c, homeostasis model assessment estimates of beta cell function and insulin resistance, and glutamic acid decarboxylase antibodies) and the same data-driven clustering technique as in previous studies. We used Cox proportional hazards models to investigate associations between clusters and risks of vascular complications and mortality. We estimated the C-index and R2 to compare predictive abilities of the clusters to those of established risk factors as continuous variables. All models included adjustment for age, sex, diabetes duration and time of inclusion.

RESULTS

We reproduced five subgroups with similar key characteristics as identified in previous studies. During median follow-up of 9-13 years (differing between outcomes), the clusters were associated with different risks of vascular complications and all-cause mortality. However, in prediction models, individual established risk factors were at least as good predictors as cluster assignment for all outcomes. For example, for retinopathy, the C-index for the model including clusters (0.65 (95% CI 0.63 to 0.68)) was similar to that of HbA1c (0.65 (95% CI 0.63 to 0.68)) or fasting C-peptide (0.66 (95% CI 0.63 to 0.68)) alone. For chronic kidney disease, the C-index for clusters (0.74 (95% CI 0.72 to 0.76)) was similar to that of triglyceride/high-density lipoprotein ratio (0.74 (95% CI 0.71 to 0.76)) or fasting C-peptide (0.74 (95% CI 0.72 to 0.76)), and baseline estimated glomerular filtration rate yielded a C-index of 0.76 (95% CI 0.74 to 0.78).

CONCLUSIONS

Cluster assignment did not provide better prediction of vascular complications or all-cause mortality compared with established risk factors.

Associations of physiologic subtypes based on HOMA2 indices of β-cell function and insulin sensitivity with the risk of kidney function decline, cardiovascular disease, and all-cause mortality from the 4C study

BACKGROUND

Previous studies have been limited by their inability to differentiate between the effects of insulin sensitivity and β-cell function on the risk of kidney function decline, cardiovascular disease (CVD), and all-cause mortality. To address this knowledge gap, we aimed to investigate whether the physiological subtypes based on homeostasis model assessment-2 (HOMA2) indices of β-cell function (HOMA2-B) and insulin sensitivity (HOMA2-S) could be used to identify individuals with subsequently high or low of clinical outcome risk.

METHODS

This retrospective cohort study included 7,317 participants with a follow-up of up to 5 years. Based on HOMA2 indices, participants were categorized into four physiologic subtypes: the normal phenotype (high insulin sensitivity and high β-cell function), the insulinopenic phenotype (high insulin sensitivity and low β-cell function), the hyperinsulinaemic phenotype (low insulin sensitivity and high β-cell function), and the classical phenotype (low insulin sensitivity and low β-cell function). The outcomes included kidney function decline, CVD events (fatal and nonfatal), and all-cause mortality. Cox regression models were used to calculate hazard ratios (HRs) for outcomes, and spline models were used to examine the dose-dependent associations of HOMA2-B and HOMA2-S with outcomes.

RESULTS

A total of 1,488 (20.3%) were classified as normal, 2,179 (29.8%) as insulinopenic, 2,173 (29.7%) as hyperinsulinemic, and 1,477 (20.2%) as classical subtypes. Compared with other physiological subtypes, the classical subtype presented the highest risk of kidney function decline (classical vs. normal HR 11.50, 95% CI 4.31-30.67). The hyperinsulinemic subtype had the highest risk of CVD and all-cause mortality (hyperinsulinemic vs. normal: fatal CVD, HR 6.56, 95% CI 3.09-13.92; all-cause mortality, HR 4.56, 95% CI 2.97-7.00). Spline analyses indicated the dose-dependent associations of HOMA2-B and HOMA2-S with outcomes.

CONCLUSIONS

The classical subtype had the strongest correlation with the risk of kidney function decline, and the hyperinsulinemic subtype had the highest risk of CVD and all-cause mortality, which should be considered for interventions with precision medicine.

Breast cancer in women with previous gestational diabetes: a nationwide register-based cohort study

BACKGROUND

Gestational diabetes mellitus (GDM) is a common pregnancy complication characterized by insulin resistance. A link has been suggested between insulin resistance and breast cancer, which is the most common cancer in women. Hence, women with previous GDM may be at increased risk of developing breast cancer, yet, the existing evidence is conflicting. This study explored the association between GDM and incident breast cancer, including age at cancer diagnosis. Additionally, we investigated the potential impact of severity of insulin resistance during pregnancy and of subsequent diabetes development on the breast cancer risk.

METHODS

We conducted a nationwide, register-based cohort study including all women giving birth in Denmark from 1997 to 2018. We defined GDM and breast cancer based on ICD-10 codes. Premenopausal and postmenopausal breast cancer was pragmatically defined as age at outcome < 50 years and ≥ 50 years, respectively. A proxy for severity of insulin resistance during pregnancy was based on insulin treatment; subsequent diabetes was defined as presence of ICD-10 codes and/or antidiabetic medication after pregnancy. The statistical analyses included Cox regression, logistic regression and t-test.

RESULTS

Of 708,121 women, 3.4% had GDM. The median follow-up period was 11.9 years (range 0-21.9). The overall breast cancer risk was comparable in women with and without previous GDM (adjusted hazard ratio 0.96 [95% CI 0.83-1.12]). Premenopausal and postmenopausal breast cancer risk also did not differ; however, women with previous GDM had a breast cancer diagnosis at younger age (42.6 vs. 43.5 years, p-value 0.01). All-cause mortality was similar regardless of GDM history. Severity of insulin resistance during pregnancy and subsequent diabetes did not affect breast cancer risk.

CONCLUSIONS

This large, population-based cohort study showed no higher risk of incident breast cancer in women with previous GDM compared to women without previous GDM after a median of almost 12 years of follow-up. This was evident irrespective of menopausal state. The breast cancer risk was not influenced by the severity of insulin resistance during pregnancy and by subsequent diabetes development. Regardless of GDM history, attention towards prevention, early detection and treatment of breast cancer should be prioritized.

The Danish Centre for Strategic Research in Type 2 Diabetes (DD2) Project Cohort and Biobank from 2010 Through 2023-A Cohort Profile Update

Purpose

This paper provides an overview of the Danish Centre for Strategic Research in Type 2 Diabetes (DD2) cohort and biobank, including baseline characteristics of participants enrolled up to 2023, and post-enrollment rates of cardiovascular disease outcomes and mortality.

Methods

Since 2010, the DD2 project has enrolled individuals with type 2 diabetes mellitus (T2DM) recently diagnosed by general practitioners and by hospital-based clinicians across Denmark. Data from questionnaires, clinical examinations, and biological samples are collected at enrollment. Additional baseline and longitudinal follow-up data are accessed via linkage to health registries.

Results

Between 2010 and 2023, the DD2 project enrolled 11,369 participants (41.3% women, median age 61.4 years). Median T2DM duration at enrollment was 1.3 years, and median BMI was 31.6 kg/m2 for women and 30.5 kg/m2 for men. 18.3% were smokers, 5.7% consumed more than 14/21 units of alcohol weekly (women/men), and 17.9% reported leisure-time physical inactivity. Original midwife records dating back >80 years revealed that 20.2% of cohort participants had birth weights <3000 g. Based on complete hospital contact history 10 years before enrollment, 20.7% of cohort participants had macrovascular complications, 17.0% had microvascular complications, and 21.7% had kidney disease based on eGFR or urine albumin-creatinine measurements. At enrollment, statins were used by 68.2%, antihypertensive drugs by 69.9%, and glucose-lowering drugs by 86.5% of individuals. Median HbA1c was 48 mmol/mol and median LDL cholesterol 2.2 mmol/L. Genome-wide genotyping and biomarker data have been analyzed for over 9000 individuals. During the current follow-up time from the enrollment date (median 7.9 years), incident cardiovascular disease rate has been 13.8 per 1000 person-years and the mortality rate has been 17.6 per 1000 person-years.

Conclusion

The DD2 cohort, with its detailed information and long-term follow up, can improve our understanding of the progression and prevention of complications among individuals with newly diagnosed T2DM.

Comparison of clustering and phenotyping approaches for subclassification of type 2 diabetes and its association with remission in Indian population

Identification of novel subgroups of type 2 diabetes (T2D) has helped improve its management. Most classification techniques focus on clustering or subphenotyping but not on both. This study aimed to compare both these methods and examine the rate of T2D remission in these subgroups in the Indian population. K-means clustering (using age at onset, HbA1C, BMI, HOMA2 IR and HOMA2%B) and subphenotyping (using homeostatic model assessment (HOMA) estimates) analysis was done on the baseline data of 281 patients with recently diagnosed T2D who participated in a 1-year online diabetes management program. Cluster analysis revealed three distinct clusters: severe insulin-deficient diabetes (SIDD), severe insulin-resistant diabetes (SIRD), and mild obesity-related diabetes (MOD) while subphenotyping showed four distinct categories: hyperinsulinemic, insulinopenic, classical, and nascent T2D. Comparison of the two approaches revealed that the clusters aligned with phenotypes based on shared characteristics of insulin sensitivity (IS) and beta cell function (BCF). Clustering correctly identified individuals in nascent group (high IS and BCF) as having mild obesity related diabetes which subphenotyping did not. Post-one-year intervention, higher remission rates were observed in the MOD cluster (p = 0.383) and the nascent phenotype showing high IS and BCF (p = 0.061, Chi-Square test). In conclusion, clustering based on a comprehensive set of parameters appears to be a superior method for classifying T2D compared with pathophysiological subphenotyping. Personalized interventions may be highly effective for newly diagnosed individuals with high IS and BCF and may result in higher remission rates in these individuals. Further large-scale studies are required to validate these findings.

Differential manifestation of type 2 diabetes in Black Africans and White Europeans with recently diagnosed type 2 diabetes: A systematic review

AIMS

The clinical manifestation of type 2 diabetes (T2D) varies across populations. We compared the phenotypic characteristics of Black Africans and White Europeans with recently diagnosed T2D to understand the ethnic differences in the manifestation of T2D.

METHODS

We searched Medline, EMBASE, CINAHL, Google Scholar, African Index Medicus, and Global Health for studies reporting information on phenotypic characteristics in Black Africans and White Europeans with recently diagnosed T2D.

RESULTS

A total of 28 studies were included in this systematic review (14 studies conducted on 2586 Black Africans in eight countries and 14 studies conducted on 279,621 White Europeans in nine countries). Compared with White Europeans, Black Africans had a lower pooled mean (95 % confidence interval) age (51.5 [48.5-54.4] years vs. 60.2 [57.9-62.6] years), body mass index (27.0 [24.2-29.8] kg/m2 vs. 31.3 [30.5-32.1] kg/m2), and a higher pooled median glycated haemoglobin (9.0 [8.0-10.3]% vs. 7.1 [6.7-7.7]%). Ugandan and Tanzanian participants had lower markers of beta-cell function and insulin resistance when compared with four White European populations.

CONCLUSION

These findings provide evidence of the ethnic differences in the manifestation of T2D, underscoring the importance of understanding the underlying factors influencing these differences and formulating ethnic-specific approaches for managing and preventing T2D.

Low-grade inflammation in persons with recently diagnosed type 2 diabetes: The role of abdominal adiposity and putative mediators

AIMS

To determine the magnitude of the association between abdominal adiposity and low-grade inflammation in persons with recently diagnosed type 2 diabetes (T2D) and to determine to what extent this association is mediated by low physical activity level, hyperinsulinaemia, hyperglycaemia, dyslipidaemia, hypertension, and comorbidities.

MATERIALS AND METHODS

We measured waist circumference, clinical characteristics, and inflammatory markers i.e. tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and high-sensitivity C-reactive protein (hsCRP), in >9000 persons with recently diagnosed T2D. We applied multiple mediation analysis using structural equation modelling, with adjustment for age and sex.

RESULTS

Waist circumference as a proxy for abdominal adiposity was positively associated with all inflammatory markers. Hence, a one-standard deviation (SD) increase in waist circumference (SD = 15 cm) was associated with a 22%, 35%, and 46% SD increase in TNF-α (SD = 1.5 pg/mL), IL-6 (SD = 4.4 pg/mL), and hsCRP (SD = 6.9 mg/L), respectively. The level of hyperinsulinaemia assessed by fasting C-peptide was quantitatively the most important mediator, accounting for 9%-25% of the association between abdominal adiposity and low-grade inflammation, followed by low physical activity (5%-7%) and high triglyceride levels (2%-6%). Although mediation of adiposity-induced inflammation by greater comorbidity and higher glycated haemoglobin levels reached statistical significance, their impact was minor (1%-2%).

CONCLUSIONS

In persons with recently diagnosed T2D, there was a clear association between abdominal adiposity and low-grade inflammation. A considerable part (20%-40%) of this association was mediated by other factors, with hyperinsulinaemia as a potentially important driver of adiposity-induced inflammation in T2D.

Risk of Diabetic Retinopathy According to Subtype of Type 2 Diabetes

Type 2 diabetes is a heterogeneous disease that can be subdivided on the basis of β-cell function and insulin sensitivity. We investigated the presence, incidence, and progression of diabetic retinopathy (DR) according to subtypes of type 2 diabetes. In a national cohort, we identified three subtypes of type 2 diabetes: classical, hyperinsulinemic, and insulinopenic type 2 diabetes, based on HOMA2 measurements. From the Danish Registry of Diabetic Retinopathy we extracted information on level of DR. We used several national health registries to link information on comorbidity, medications, and laboratory tests. We found individuals with hyperinsulinemic type 2 diabetes were less likely to have DR at entry date compared with those with classical type 2 diabetes, whereas individuals with insulinopenic type 2 diabetes were more likely to have DR. In multivariable Cox regression analysis, individuals with hyperinsulinemic type 2 diabetes had a decreased risk of both incidence and progression of DR compared to those with classical type 2 diabetes. We did not find any clear difference in risk of incident or progression of DR in individuals with insulinopenic compared to classical type 2 diabetes. These findings indicate that subcategorization of type 2 diabetes is important in evaluating the risk of DR.

ARTICLE HIGHLIGHTS

Challenges and pitfalls of youth-onset type 2 diabetes

The incidence and prevalence of youth-onset type 2 diabetes mellitus (T2DM) are increasing. The rise in frequency and severity of childhood obesity, inclination to sedentary lifestyle, and epigenetic risks related to prenatal hyperglycemia exposure are important drivers of the youth-onset T2DM epidemic and might as well be responsible for the early onset of diabetes complications. Indeed, youth-onset T2DM has a more extreme metabolic phenotype than adult-onset T2DM, with greater insulin resistance and more rapid deterioration of beta cell function. Therefore, intermediate complications such as microalbuminuria develop in late childhood or early adulthood, while end-stage complications develop in mid-life. Due to the lack of efficacy and safety data, several drugs available for the treatment of adults with T2DM have not been approved in youth, reducing the pharmacological treatment options. In this mini review, we will try to address the present challenges and pitfalls related to youth-onset T2DM and summarize the available interventions to mitigate the risk of microvascular and macrovascular complications.

Diabetes and the Microvasculature of the Bone and Marrow

PURPOSE OF REVIEW

The purpose of this review is to highlight the evidence of microvascular dysfunction in bone and marrow and its relation to poor skeletal outcomes in diabetes mellitus.

RECENT FINDINGS

Diabetes mellitus is characterized by chronic hyperglycemia, which may lead to microangiopathy and macroangiopathy. Micro- and macroangiopathy have been diagnosed in Type 1 and Type 2 diabetes, coinciding with osteopenia, osteoporosis, enhanced fracture risk and delayed fracture healing. Microangiopathy has been reported in the skeleton, correlating with reduced blood flow and perfusion, vasomotor dysfunction, microvascular rarefaction, reduced angiogenic capabilities, and augmented vascular permeability. Microangiopathy within the skeleton may be detrimental to bone and manifest as, among other clinical abnormalities, reduced mass, enhanced fracture risk, and delayed fracture healing. More investigations are required to elucidate the various mechanisms by which diabetic microvascular dysfunction impacts the skeleton.

Associations between insulin-like growth factor binding protein-2 and insulin sensitivity, metformin, and mortality in persons with T2D

AIMS

Serum insulin-like growth factor binding protein-2 (IGFBP-2) is low in persons with type 2 diabetes mellitus (T2D) and possibly regulated by metformin. Counter-intuitively, high IGFBP-2 associates with mortality. We investigated the association between IGFBP-2, metformin-treatment, and indices of insulin sensitivity, and assessed IGFBP-2 in relation to prior comorbidity and mortality during five-year follow-up.

METHODS

The study included 859 treatment-naive and 558 metformin-treated persons enrolled in the Danish Centre for Strategic Research in T2D and followed for 4.9 (3.9-5.9) years through national health registries. All proteins were determined in serum collected at enrollment.

RESULTS

Following adjustment for age, metformin-treated and treatment-naive persons has similar IGFBP-2 levels. Low IGFBP-2 level was associated with increased BMI, fasting glucose, and C-peptide. IGFBP-2 was higher in the 437 persons who had comorbidities at enrollment than in those with T2D only (343 (213;528) vs. 242 (169;378) ng/mL). During follow-up, 87 persons died, and IGFBP-2 predicted mortality with an unadjusted HR (95% CI) per doubling in IGFBP-2 concentration of 2.62 (2.04;3.37) and a HR of 2.21 (1.61;3.01) following full adjustment.

CONCLUSIONS

In T2D, high IGFBP-2 associates with low glucose and insulin secretion, is unaffected by metformin treatment, and associates with risk of prior comorbidity and mortality.

Precision subclassification of type 2 diabetes: a systematic review

BACKGROUND

Heterogeneity in type 2 diabetes presentation and progression suggests that precision medicine interventions could improve clinical outcomes. We undertook a systematic review to determine whether strategies to subclassify type 2 diabetes were associated with high quality evidence, reproducible results and improved outcomes for patients.

METHODS

We searched PubMed and Embase for publications that used 'simple subclassification' approaches using simple categorisation of clinical characteristics, or 'complex subclassification' approaches which used machine learning or 'omics approaches in people with established type 2 diabetes. We excluded other diabetes subtypes and those predicting incident type 2 diabetes. We assessed quality, reproducibility and clinical relevance of extracted full-text articles and qualitatively synthesised a summary of subclassification approaches.

RESULTS

Here we show data from 51 studies that demonstrate many simple stratification approaches, but none have been replicated and many are not associated with meaningful clinical outcomes. Complex stratification was reviewed in 62 studies and produced reproducible subtypes of type 2 diabetes that are associated with outcomes. Both approaches require a higher grade of evidence but support the premise that type 2 diabetes can be subclassified into clinically meaningful subtypes.

CONCLUSION

Critical next steps toward clinical implementation are to test whether subtypes exist in more diverse ancestries and whether tailoring interventions to subtypes will improve outcomes.

Low Bone Turnover Associates With Lower Insulin Sensitivity in Newly Diagnosed Drug-Naïve Persons With Type 2 Diabetes

CONTEXT

Bone turnover markers (BTMs) are lower in type 2 diabetes mellitus (T2D). The relationships between bone turnover, β-cell function, and insulin sensitivity in T2D are uncertain.

OBJECTIVE

To investigate if fasting levels of BTMs in persons with T2D are associated with β-cell function or insulin sensitivity.

METHODS

We defined three T2D phenotypes, the insulinopenic (low β-cell function, high insulin sensitivity), the classical (low β-cell function, low insulin sensitivity), and the hyperinsulinemic (high β-cell function, low insulin sensitivity) phenotypes, in the Danish Centre for Strategic Research T2D cohort using the homeostatic model assessment. We selected age- and gender-matched subgroups to represent the three T2D phenotypes, yielding 326 glucose-lowering treatment-naïve persons with T2D. Median values of BTMs between the three T2D phenotypes were compared. Regression models were applied to assess the association between BTMs, β-cell function, and insulin sensitivity adjusted for potential confounders.

RESULTS

Median serum levels of procollagen type I N-terminal propeptide, C-terminal telopeptide of type I collagen, and osteocalcin were higher in the insulinopenic phenotype (52.3 μg/L, IQR 41.6, 63.3; 259.4 ng/L, IQR 163.4, 347.7; and 18.0 μg/L, IQR 14.4, 25.2, respectively) compared with the classical (41.4, IQR 31.0, 51.4; 150.4 IQR 103.5, 265.1; 13.1, IQR 10.0, 17.6, respectively) and the hyperinsulinemic (43.7, IQR 32.3, 57.3; 163.3, IQR 98.9, 273.1; 15.7 IQR 10.2, 20.8, respectively) phenotypes (all P < .01). These differences persisted after adjustment for age, sex, waist to hip ratio, or fasting plasma glucose (P < .01).

CONCLUSION

BTMs are lower in newly diagnosed persons with T2D characterized by low insulin sensitivity.

Systematic review of precision subclassification of type 2 diabetes

Heterogeneity in type 2 diabetes presentation, progression and treatment has the potential for precision medicine interventions that can enhance care and outcomes for affected individuals. We undertook a systematic review to ascertain whether strategies to subclassify type 2 diabetes are associated with improved clinical outcomes, show reproducibility and have high quality evidence. We reviewed publications that deployed 'simple subclassification' using clinical features, biomarkers, imaging or other routinely available parameters or 'complex subclassification' approaches that used machine learning and/or genomic data. We found that simple stratification approaches, for example, stratification based on age, body mass index or lipid profiles, had been widely used, but no strategy had been replicated and many lacked association with meaningful outcomes. Complex stratification using clustering of simple clinical data with and without genetic data did show reproducible subtypes of diabetes that had been associated with outcomes such as cardiovascular disease and/or mortality. Both approaches require a higher grade of evidence but support the premise that type 2 diabetes can be subclassified into meaningful groups. More studies are needed to test these subclassifications in more diverse ancestries and prove that they are amenable to interventions.

Subtypes of type 2 diabetes and their association with outcomes in Korean adults - A cluster analysis of community-based prospective cohort

BACKGROUND

Little is known about the subtypes of type 2 diabetes (T2D) and their association with clinical outcomes in Asians.

METHODS

We performed data-driven cluster analysis in patients with newly diagnosed drug-naive T2D (n = 756) from the Korean Genome and Epidemiology Study. Clusters were based on five variables (age at diagnosis, BMI, HbA1c, and HOMA2 β-cell function, and insulin resistance).

RESULTS

We identified four clusters of patients with T2D according to k-means clustering: cluster 1 (22.4 %, severe insulin-resistant diabetes [SIRD]), cluster 2 (32.7 %, mild age-related diabetes [MARD]), cluster 3 (32.7 %, mild obesity-related diabetes [MOD]), and cluster 4 (12.3 %, severe insulin-deficient diabetes [SIDD]). During 14 years of follow-up, individuals in the SIDD cluster had the highest risk of initiation of glucose-lowering therapy compared to individuals in the other three clusters. Individuals in the MARD and SIDD clusters showed the highest risk of chronic kidney disease and cardiovascular disease, and individuals in the MOD clusters showed the lowest risk after adjusting for other risk factors (P < 0.05).

CONCLUSIONS

Patients with T2D can be categorized into four subgroups with different glycemic deterioration and risks of diabetes complications. Individualized management might be helpful for better clinical outcomes in Asian patients with different T2D subgroups.

Microbiome Features Differentiating Unsupervised-Stratification-Based Clusters of Patients with Abnormal Glycometabolism

The alteration of gut microbiota structure plays a pivotal role in the pathogenesis of abnormal glycometabolism. However, the microbiome features identified in patient groups stratified solely based on glucose levels remain controversial among different studies. In this study, we stratified 258 participants (discovery cohort) into three clusters according to an unsupervised method based on 16 clinical parameters involving the levels of blood glucose, insulin, and lipid. We found 67 cluster-specific microbiome features (i.e., amplicon sequence variants [ASVs]) based on 16S rRNA gene V3-V4 region sequencing. Specifically, ASVs belonging to Barnesville and Alistipes were enriched in cluster 1, in which participants had the lowest blood glucose levels, high insulin sensitivity, and a high-fecal short-chain fatty acid concentration. ASVs belonging to Prevotella copri and Ruminococcus gnavus were enriched in cluster 2, which was characterized by a moderate level of blood glucose, serious insulin resistance, and high levels of cholesterol and triglyceride. Cluster 3 was characterized by a high level of blood glucose and insulin deficiency, enriched with ASVs in P. copri and Bacteroides vulgatus. In addition, machine learning classifiers using the 67 cluster-specific ASVs were used to distinguish individuals in one cluster from those in the other two clusters both in discovery and testing cohorts (n = 83). Therefore, microbiome features identified based on the unsupervised stratification of patients with more inclusive clinical parameters may better reflect microbiota alterations associated with the progression of abnormal glycometabolism. IMPORTANCE The gut microbiota is altered in patients with type 2 diabetes (T2D) and prediabetes. The association of particular bacteria with T2D, however, varied among studies, which has made it challenging to develop precision medicine approaches for the prevention and alleviation of T2D. Blood glucose level is the only parameter in clustering patients when identifying the T2D-related bacteria in previous studies. This stratification ignores the fact that patients within the same blood glucose range differ in their insulin resistance and dyslipidemia, which also may be related to disordered gut microbiota. In addition to parameters of blood glucose levels, we also used additional parameters involving insulin and lipid levels to stratify participants into three clusters and further identified cluster-specific microbiome features. We further validated the association between these microbiome features and glycometabolism with an independent cohort. This study highlights the importance of stratification of patients with blood glucose, insulin, and lipid levels when identifying the microbiome features associated with the progression of abnormal glycometabolism.

Post-Load Insulin Secretion Patterns are Associated with Glycemic Status and Diabetic Complications in Patients with Type 2 Diabetes Mellitus

BACKGROUND

To examine whether the different patterns of post-load insulin secretion can identify the heterogeneity of type 2 diabetes mellitus (T2DM).

METHODS

Six hundred twenty-five inpatients with T2DM at Jining No. 1 People's Hospital were recruited from January 2019 to October 2021. The 140 g steamed bread meal test (SBMT) was conducted on patients with T2DM, and glucose, insulin, and C-peptide levels were recorded at 0, 60, 120, and 180 min. To avoid the effect of exogenous insulin, patients were categorized into three different classes by latent class trajectory analysis based on the post-load secretion patterns of C-peptide. The difference in short- and long-term glycemic status and prevalence of complications distributed among the three classes were compared by multiple linear regression and multiple logistic regression, respectively.

RESULTS

There were significant differences in long-term glycemic status (e. g., HbA1c) and short-term glycemic status (e. g., mean blood glucose, time in range) among the three classes. The difference in short-term glycemic status was similar in terms of the whole day, daytime, and nighttime. The prevalence of severe diabetic retinopathy and atherosclerosis showed a decreasing trend among the three classes.

CONCLUSIONS

The post-load insulin secretion patterns could well identify the heterogeneity of patients with T2DM in short- and long-term glycemic status and prevalence of complications, providing recommendations for the timely adjustment in treatment regimes of patients with T2DM and promotion of personalized treatment.

The role of cereal soluble fiber in the beneficial modulation of glycometabolic gastrointestinal hormones

According to cohort studies, cereal fiber, and whole-grain products might decrease risk for type 2 diabetes (T2DM), inflammatory processes, cancer, and cardiovascular diseases. These associations, mainly affect insoluble, but not soluble cereal fiber. In intervention studies, soluble fiber elicit anti-hyperglycemic and anti-inflammatory short-term effects, partially explained by fermentation to short-chain fatty acids, which acutely counteract insulin resistance and inflammation. ß-glucans lower cholesterol levels and possibly reduce liver fat. Long-term benefits are not yet shown, maybe caused by T2DM heterogeneity, as insulin resistance and fatty liver disease - the glycometabolic points of action of soluble cereal fiber - are not present in every patient. Thus, only some patients might be susceptive to fiber. Also, incretin action in response to fiber could be a relevant factor for variable effects. Thus, this review aims to summarize the current knowledge from human studies on the impact of soluble cereal fiber on glycometabolic gastrointestinal hormones. Effects on GLP-1 appear to be highly contradictory, while these fibers might lower GIP and ghrelin, and increase PYY and CCK. Even though previous results of specific trials support a glycometabolic benefit of soluble fiber, larger acute, and long-term mechanistic studies are needed in order to corroborate the results.

Predicting Factors for Metabolic Non-Response to a Complex Lifestyle Intervention-A Replication Analysis to a Randomized-Controlled Trial

BACKGROUND

T2DM heterogeneity affects responsiveness to lifestyle treatment. Beta-cell failure and nonalcoholic fatty liver disease (NAFLD) independently predict T2DM, but NAFLD inconsistently predicts metabolic response to lifestyle intervention.

AIM

We attempt to replicate a prediction model deducted from the Tübinger Lifestyle Intervention Program by assessing similar metabolic factors to predict conversion to normal glucose regulation (NGR) in a comparable lifestyle intervention trial.

METHODS

In the Optimal Fiber Trial (OptiFiT), 131 Caucasian participants with prediabetes completed a one-year lifestyle intervention program and received a fiber or placebo supplement. We compared baseline parameters for responders and non-responders, assessed correlations of major metabolic changes and conducted a logistic regression analysis for predictors of remission to NGR.

RESULTS

NGR was achieved by 33 participants, respectively. At baseline, for the placebo group only, 1 h and 2 h glucose levels, glucose AUC and Cederholm index predicted conversion to NGR. HOMA-beta, HOMA-IR or liver fat indices did not differ between responders and non-responders of the placebo or the fiber group. Changes in waist circumference or fatty liver index correlated with changes in glycemia and insulin resistance, but not with changes in insulin secretion. Insulin-resistant NAFLD did not predict non-response. Differences in compliance did not explain the results.

CONCLUSIONS

Higher post-challenge glucose levels strongly predicted the metabolic non-response to complex lifestyle intervention in our cohort. Depending on the specific intervention and the investigated cohort, fasting glucose levels and insulin sensitivity might contribute to the risk pattern. Beta-cell function did not improve in accordance with other metabolic improvements, qualifying as a potential risk factor for non-response. We could not replicate previous data suggesting that an insulin-resistant fatty liver is a specific risk factor for treatment failure. Replication studies are required.

Phenotypic and genetic classification of diabetes

The historical subclassification of diabetes into predominantly types 1 and 2 is well appreciated to inadequately capture the heterogeneity seen in patient presentations, disease course, response to therapy and disease complications. This review summarises proposed data-driven approaches to further refine diabetes subtypes using clinical phenotypes and/or genetic information. We highlight the benefits as well as the limitations of these subclassification schemas, including practical barriers to their implementation that would need to be overcome before incorporation into clinical practice.

Insulin resistance and beta-cell dysfunction in newly diagnosed type 2 diabetes: Expression, aggregation and predominance. Verona Newly Diagnosed Type 2 Diabetes Study 10

AIMS

We investigated quantitative expression, mutual aggregation and relation with hyperglycemia of insulin resistance (IR) and beta-cell dysfunction (BCD) in newly diagnosed type 2 diabetes.

METHODS

We assessed IR with euglycemic hyperinsulinemic clamp and BCD with modelled glucose/C-peptide response to oral glucose in 729 mostly drug-naïve patients. We measured glycated hemoglobin, pre-prandial, post-prandial and meal-related excursion of blood glucose.

RESULTS

IR was found in 87.8% [95% confidence intervals 85.4-90.2] and BCD in 90.0% [87.8-92.2] of subjects, ranging from mild to moderate or severe. Approximately 20% of subjects had solely one defect: BCD 10.8% [8.6-13.1] or IR 8.6% [6.6-10.7]. Insulin resistance and BCD aggregated in most subjects (79.1% [76.2-82.1]). We arbitrarily set nine possible combinations of mild, moderate or severe IR and mild, moderate or severe BCD, finding that each had a similar frequency (∼10%). In multiple regression analyses parameters of glucose control were related more strongly with BCD than with IR.

CONCLUSIONS

In newly-diagnosed type 2 diabetes, IR and BCD are very common with a wide range of expression but no specific pattern of aggregation. Beta-cell dysfunction is likely to play a greater quantitative role than IR in causing/sustaining hyperglycemia in newly-diagnosed type 2 diabetes.

Apparent Insulin Deficiency in an Adult African Population With New-Onset Type 2 Diabetes

Identifying patients with new-onset type 2 diabetes who have insulin deficiency can aid in timely insulin replacement therapy. In this study, we measured fasting C-peptide concentration to assess endogenous insulin secretion and determine the prevalence and characteristics of patients with insulin deficiency in adult Ugandan patients with confirmed type 2 diabetes at presentation.

Methods

Adult patients with new-onset diabetes were recruited from seven tertiary hospitals in Uganda. Participants who were positive for the three islet autoantibodies were excluded. Fasting C-peptide concentrations were measured in 494 adult patients, and insulin deficiency was defined as a fasting C-peptide concentration <0.76 ng/ml. The socio-demographic, clinical, and metabolic characteristics of participants with and without insulin deficiency were compared. Multivariate analysis was performed to identify independent predictors of insulin deficiency.

Results

The median (IQR) age, glycated haemoglobin (HbA1c), and fasting C-peptide of the participants was 48 (39-58) years,10.4 (7.7-12.5) % or 90 (61-113) mmol/mol, and 1.4 (0.8-2.1) ng/ml, respectively. Insulin deficiency was present in 108 (21.9%) participants. Participants with confirmed insulin deficiency were more likely to be male (53.7% vs 40.4%, p=0.01), and had a lower body mass index or BMI [p<0.001], were less likely to be hypertensive [p=0.03], had reduced levels of triglycerides, uric acid, and leptin concentrations [p<0.001]), but higher HbA1c concentration (p=0.004). On multivariate analysis, BMI (AOR 0.89, 95% CI 0.85-0.94, p<0.001), non-HDLC (AOR 0.77, 95% CI 0.61-0.97, p=0.026), and HbA1c concentrations (AOR 1.08, 95% CI 1.00-1.17, p=0.049) were independent predictors of insulin deficiency.

Conclusion

Insulin deficiency was prevalent in this population, occurring in about 1 in every 5 patients. Participants with insulin deficiency were more likely to have high HbA1c and fewer markers of adiposity and metabolic syndrome. These features should increase suspicion of insulin deficiency and guide targeted testing and insulin replacement therapy.

β-Cell Succinate Dehydrogenase Deficiency Triggers Metabolic Dysfunction and Insulinopenic Diabetes

Mitochondrial dysfunction plays a central role in type 2 diabetes (T2D); however, the pathogenic mechanisms in pancreatic β-cells are incompletely elucidated. Succinate dehydrogenase (SDH) is a key mitochondrial enzyme with dual functions in the tricarboxylic acid cycle and electron transport chain. Using samples from human with diabetes and a mouse model of β-cell-specific SDH ablation (SDHBβKO), we define SDH deficiency as a driver of mitochondrial dysfunction in β-cell failure and insulinopenic diabetes. β-Cell SDH deficiency impairs glucose-induced respiratory oxidative phosphorylation and mitochondrial membrane potential collapse, thereby compromising glucose-stimulated ATP production, insulin secretion, and β-cell growth. Mechanistically, metabolomic and transcriptomic studies reveal that the loss of SDH causes excess succinate accumulation, which inappropriately activates mammalian target of rapamycin (mTOR) complex 1-regulated metabolic anabolism, including increased SREBP-regulated lipid synthesis. These alterations, which mirror diabetes-associated human β-cell dysfunction, are partially reversed by acute mTOR inhibition with rapamycin. We propose SDH deficiency as a contributing mechanism to the progressive β-cell failure of diabetes and identify mTOR complex 1 inhibition as a potential mitigation strategy.

Evaluation of the value of conventional and unconventional lipid parameters for predicting the risk of diabetes in a non-diabetic population

BACKGROUND

Conventional and unconventional lipid parameters are associated with diabetes risk, the comparative studies on lipid parameters for predicting future diabetes risk, however, are still extremely limited, and the value of conventional and unconventional lipid parameters in predicting future diabetes has not been evaluated. This study was designed to determine the predictive value of conventional and unconventional lipid parameters for the future development of diabetes.

METHODS

The study was a longitudinal follow-up study of 15,464 participants with baseline normoglycemia. At baseline, conventional lipid parameters such as low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) were measured/calculated, and unconventional lipid parameters such as non-HDL-C, remnant cholesterol (RC), LDL/HDL-C ratio, TG/HDL-C ratio, non-HDL/HDL-C ratio, TC/HDL-C ratio and RC/HDL-C ratio were calculated. Hazard ratio (HR) and 95% confidence interval (CI) were estimated by Cox proportional hazard regression adjusting for demographic and diabetes-related risk factors. The predictive value and threshold fluctuation intervals of baseline conventional and unconventional lipid parameters for future diabetes were evaluated by the time-dependent receiver operator characteristics (ROC) curve.

RESULTS

The incidence rate of diabetes was 3.93 per 1000 person-years during an average follow-up period of 6.13 years. In the baseline non-diabetic population, only TG and HDL-C among the conventional lipid parameters were associated with future diabetes risk, while all the unconventional lipid parameters except non-HDL-C were significantly associated with future diabetes risk. In contrast, unconventional lipid parameters reflected diabetes risk better than conventional lipid parameters, and RC/HDL-C ratio was the best lipid parameter to reflect the risk of diabetes (HR: 6.75, 95% CI 2.40-18.98). Sensitivity analysis further verified the robustness of this result. Also, time-dependent ROC curve analysis showed that RC, non-HDL/HDL-C ratio, and TC/HDL-C ratio were the best lipid parameters for predicting the risk of medium-and long-term diabetes.

CONCLUSIONS

Unconventional lipid parameters generally outperform conventional lipid parameters in assessing and predicting future diabetes risk. It is suggested that unconventional lipid parameters should also be routinely evaluated in clinical practice.

A Normalized Real-Life Glucose Profile After Diet-Induced Remission of Type 2 Diabetes: A Pilot Trial

Background/objective

Type 2 diabetes related to metabolic syndrome is often partially reversible after weight loss. We conducted a pilot trial on whether complete remission to the point of a normalized real-life glucose profile, measured by continuous subcutaneous monitoring, can be achieved.

Methods

We conducted a mono-center, single-arm intervention trial between January 20, 2020, and January 12, 2021, in Munich, Germany. Ten participants had type 2 diabetes related to metabolic syndrome for a maximum of six years. They received a six-month lifestyle intervention including up to three months of a very-low-calorie formula diet, followed by stepwise food reintroduction and regular behavioral lifestyle counseling. The primary outcome was the status of glucose control at the end of the intervention. Complete remission was defined as normalization of the real-life glucose profile without glucose-lowering medication over at least five days. We measured anthropometric and biochemical parameters, body fat distribution by MRI, and insulin secretory reserve by an arginine stimulation test.

Results

Seven participants completed the trial, one reached complete remission, three achieved partial remission, and three displayed improved glucose control still in the diabetic range. A reduction of median glycosylated hemoglobin by −10 mmol/mol (−22.0 to −5.0; p = 0.016) co-occurred with weight loss of −6.4 kg (−14.2 to −3.5; p = 0.031). The insulin secretory reserve remained unchanged.

Conclusions

Complete remission of type 2 diabetes related to metabolic syndrome to the point of a normalized real-life glucose profile is possible through lifestyle intervention. Full intervention success remains challenging even with intensive counseling and support.

Type 2 diabetes classification: a data-driven cluster study of the Danish Centre for Strategic Research in Type 2 Diabetes (DD2) cohort

INTRODUCTION

A Swedish data-driven cluster study identified four distinct type 2 diabetes (T2D) clusters, based on age at diagnosis, body mass index (BMI), hemoglobin A1c (HbA1c) level, and homeostatic model assessment 2 (HOMA2) estimates of insulin resistance and beta-cell function. A Danish study proposed three T2D phenotypes (insulinopenic, hyperinsulinemic, and classical) based on HOMA2 measures only. We examined these two new T2D classifications using the Danish Centre for Strategic Research in Type 2 Diabetes cohort.

RESEARCH DESIGN AND METHODS

In 3529 individuals, we first performed a k-means cluster analysis with a forced k-value of four to replicate the Swedish clusters: severe insulin deficient (SIDD), severe insulin resistant (SIRD), mild age-related (MARD), and mild obesity-related (MOD) diabetes. Next, we did an analysis open to alternative k-values (ie, data determined the optimal number of clusters). Finally, we compared the data-driven clusters with the three Danish phenotypes.

RESULTS

Compared with the Swedish findings, the replicated Danish SIDD cluster included patients with lower mean HbA1c (86 mmol/mol vs 101 mmol/mol), and the Danish MOD cluster patients were less obese (mean BMI 32 kg/m² vs 36 kg/m²). Our data-driven alternative k-value analysis suggested the optimal number of T2D clusters in our data to be three, rather than four. When comparing the four replicated Swedish clusters with the three proposed Danish phenotypes, 81%, 79%, and 69% of the SIDD, MOD, and MARD patients, respectively, fitted the classical T2D phenotype, whereas 70% of SIRD patients fitted the hyperinsulinemic phenotype. Among the three alternative data-driven clusters, 60% of patients in the most insulin-resistant cluster constituted 76% of patients with a hyperinsulinemic phenotype.

CONCLUSION

Different HOMA2-based approaches did not classify patients with T2D in a consistent manner. The T2D classes characterized by high insulin resistance/hyperinsulinemia appeared most distinct.

Impaired bone fracture healing in type 2 diabetes is caused by defective functions of skeletal progenitor cells

The mechanisms of obesity and type 2 diabetes (T2D)-associated impaired fracture healing are poorly studied. In a murine model of T2D reflecting both hyperinsulinemia induced by high fat diet (HFD) and insulinopenia induced by treatment with streptozotocin (STZ), we examined bone healing in a tibia cortical bone defect. A delayed bone healing was observed during hyperinsulinemia as newly formed bone was reduced by – 28.4±7.7% and was associated with accumulation of marrow adipocytes at the defect site +124.06±38.71%, and increased density of SCA1+ (+74.99± 29.19%) but not Runx2 +osteoprogenitor cells. We also observed increased in reactive oxygen species production (+101.82± 33.05%), senescence gene signature (≈106.66± 34.03%) and LAMIN B1 - senescent cell density (+225.18± 43.15%), suggesting accelerated senescence phenotype. During insulinopenia, a more pronounced delayed bone healing was observed with decreased newly formed bone to -34.9± 6.2% which was inversely correlated with glucose levels (R 2=0.48, p&lt;0.004) and callus adipose tissue area (R 2=0.3711, p&lt;0.01). Finally, to investigate the relevance to human physiology, we observed that sera from obese and T2D subjects had disease state-specific inhibitory effects on osteoblast related gene signatures in human bone marrow stromal cells which resulted in inhibition of osteoblast and enhanced adipocyte differentiation. Our data demonstrate that T2D exerts negative effects on bone healing through inhibition of osteoblast differentiation of skeletal stem cells and induction of accelerated bone senescence and that the hyperglycaemia per se and not just insulin levels is detrimental for bone healing.

Clinical and biochemical characteristics of postpancreatitis diabetes mellitus: A cross-sectional study from the Danish nationwide DD2 cohort

BACKGROUND

Postpancreatitis diabetes mellitus (PPDM) is a common metabolic sequalae of acute and chronic pancreatitis. We conducted a cross-sectional study to examine the proportion of PPDM among patients clinically diagnosed with type 2 diabetes (T2D) in Denmark and their clinical and biochemical characteristics.

METHODS

We identified all past diagnoses of pancreatitis among patients in the Danish Centre for Strategic Research in Type 2 Diabetes (DD2) cohort through linkage with national health registries. Using International Classification of Diseases, Tenth Revision codes we categorized patients as PPDM and further divided them into acute/chronic subtypes (PPDM-A and PPDM-C). We assessed PPDM prevalence and examined associations with clinical and biochemical parameters using log binomial or Poisson regression to calculate age-/sex-adjusted prevalence ratios (aPRs).

RESULTS

Among 5564 patients with a clinical diagnosis of T2D, 78 (1.4%) had PPDM. Compared to T2D, PPDM patients were more often underweight or normal weight (body mass index ≤25.0 kg/m² : aPR 2.3; 95% confidence interval [CI]: 1.6-3.2) and had lower waist-to-hip ratio (≤0.95/≤0.80 in men/women: aPRs 1.8; 95% CI: 1.2-2.7). PPDM patients had lower plasma amylase levels (<17 U/L: aPRs 2.2; 95% CI: 1.1-4.3), higher insulin sensitivity (homeostatic model assessment 2S [HOMA2S] >63: aPR 2.0; 95% CI: 1.2-3.2) and tended to have worse glycaemic control (HbA1c ≥8.0%: aPRs 1.4; 95% CI: 0.8-2.4). PPDM-A was largely indistinguishable from T2D, whereas PPDM-C had impaired insulin secretion, higher insulin sensitivity, and worse glycemic control.

CONCLUSIONS

The proportion of PPDM among patients with clinically diagnosed T2D is ~1.5% in an everyday clinical care setting. Glucose metabolism of PPDM-A is largely indistinguishable from T2D, whereas PPDM-C differs in relation to insulin secretion and sensitivity.

Dyslipidemia and diabetes mellitus: Role of lipoprotein species and interrelated pathways of lipid metabolism in diabetes mellitus

Diabetes mellitus is a complex disease. We are increasingly gaining a better understanding of its mechanisms at the molecular level. From these new insights, better therapeutic approaches should emerge. Diabetes mellitus is a syndrome with many associated subphenotypes. These include mitochondrial disorders, lipodystrophies, and inflammatory disorders involving cytokines. Levels of sphingosine-1-phosphate, which has recently been shown to play a role in glucose homeostasis, are low in diabetics, whereas levels of ceramides are increased. Major phenotypes associated with diabetes mellitus are dyslipidemias, notably hypertriglyceridemia and low high-density lipoprotein cholesterol levels. Both diabetes and dyslipidemia are strongly associated with increased risk for atherosclerotic vascular disease.

Microvascular Disease and Risk of Cardiovascular Events and Death From Intensive Treatment in Type 2 Diabetes: The ACCORDION Study

OBJECTIVE

To assess whether the presence of microvascular complications modifies the effect of intensive glucose reduction on long-term outcomes in patients with type 2 diabetes.

PATIENTS AND METHODS

Using ACCORD and ACCORDION study data, we investigated the risk of the primary outcome (nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death) or death in relation to the prerandomization type and extent of microvascular complications. Interaction terms were fitted in survival models to estimate the risk of both outcomes across levels of an overall microvascular disease score (range 0 to 100) and its individual components: diabetic nephropathy, retinopathy, and neuropathy.

RESULTS

During a mean follow-up of 7.7 years, 1685 primary outcomes and 1806 deaths occurred in 9405 participants. The outcome-specific microvascular score was ≤30 in 97.9% of subjects for the primary outcome and in 98.5% for death. For participants with scores of 0 and 30, respectively, the 10-year absolute risk difference between intensive glucose control and standard treatment ranged from -0.8% (95% CI, -2.6, 1.1) to -3.0% -7.1, 1.1) for the primary outcome and from -0.5% (-2.1, 1.1) to 0.7% (-4.2, 5.6) for mortality. Retinopathy was associated with the largest effects, with a 10-year absolute risk difference of -6.5% (-11.1 to -2.0) for the primary outcome and -3.9% (-7.8 to 0.1) for mortality.

CONCLUSION

This hypothesis-generating study identifies diabetic retinopathy as predictor of the beneficial effect of intensive glucose control on the risk of cardiovascular disease and possibly death. Further long-term studies are required to confirm these findings.

A Pathophysiology of Type 2 Diabetes Unrelated to Metabolic Syndrome

OBJECTIVE

Clinically, type 2 diabetes mellitus (T2DM) is heterogeneous, but the prevailing pathophysiologic hypothesis nevertheless contends that components of metabolic syndrome are central to all cases of T2DM. Here, we re-evaluated this hypothesis.

RESEARCH DESIGN AND METHODS

We conducted a cross-sectional analysis of 138 women from the monocenter, post gestational diabetes study PPSDiab, 73 of which had incident prediabetes or T2DM. Additionally, we examined all the 412 incident cases of T2DM in phases 3 to 9 of the Whitehall II study in comparison to healthy controls. Our analysis included a medical history, anthropometrics, oral glucose tolerance testing, and laboratory chemistry in both studies. Additional analyses from the PPSDiab Study consisted of cardiopulmonary exercise testing, magnetic resonance imaging, auto-antibody testing, and the exclusion of glucokinase maturity-onset diabetes of the young.

RESULTS

We found that 33 (45%) of the women with prediabetes or T2DM in the PPSDiab study displayed no components of metabolic syndrome. They reached no point for metabolic syndrome in the National Cholesterol Education Program Adult Treatment Panel III score other than hyperglycemia and, moreover, had levels of liver fat content, plasma triglycerides, high-density lipoprotein cholesterol, c-reactive protein, and blood pressure that were comparable to healthy controls. In the Whitehall II study, 62 (15%) of the incident T2DM cases fulfilled the same criteria. In both studies, these cases without metabolic syndrome revealed insulin resistance and inadequately low insulin secretion.

CONCLUSIONS

Our results contradict the hypothesis that components of metabolic syndrome are central to all cases of T2DM. Instead, they suggest the common occurrence of a second, unrelated pathophysiology.

Neurovascular Dysregulation During Exercise in Type 2 Diabetes

Emerging evidence suggests that type 2 diabetes (T2D) may impair the ability to properly adjust the circulation during exercise with augmented blood pressure (BP) and an attenuated contracting skeletal muscle blood flow (BF) response being reported. This review provides a brief overview of the current understanding of these altered exercise responses in T2D and the potential underlying mechanisms, with an emphasis on the sympathetic nervous system and its regulation during exercise. The research presented support augmented sympathetic activation, heightened BP, reduced skeletal muscle BF, and impairment in the ability to attenuate sympathetically mediated vasoconstriction (i.e., functional sympatholysis) as potential drivers of neurovascular dysregulation during exercise in T2D. Furthermore, emerging evidence supporting a contribution of the exercise pressor reflex and central command is discussed along with proposed future directions for studies in this important area of research.

Pathophysiology-based subphenotyping of individuals at elevated risk for type 2 diabetes

The state of intermediate hyperglycemia is indicative of elevated risk of developing type 2 diabetes1. However, the current definition of prediabetes neither reflects subphenotypes of pathophysiology of type 2 diabetes nor is predictive of future metabolic trajectories. We used partitioning on variables derived from oral glucose tolerance tests, MRI-measured body fat distribution, liver fat content and genetic risk in a cohort of extensively phenotyped individuals who are at increased risk for type 2 diabetes2,3 to identify six distinct clusters of subphenotypes. Three of the identified subphenotypes have increased glycemia (clusters 3, 5 and 6), but only individuals in clusters 5 and 3 have imminent diabetes risks. By contrast, those in cluster 6 have moderate risk of type 2 diabetes, but an increased risk of kidney disease and all-cause mortality. Findings were replicated in an independent cohort using simple anthropomorphic and glycemic constructs4. This proof-of-concept study demonstrates that pathophysiological heterogeneity exists before diagnosis of type 2 diabetes and highlights a group of individuals who have an increased risk of complications without rapid progression to overt type 2 diabetes.

Substantial inter-individual variations in insulin secretion and sensitivity across the glucometabolic spectrum

Impaired insulin secretion and action are important for development of type 2 diabetes (T2D) and metabolic syndrome (MetS). Despite recognized heterogeneity of these glucometabolic disorders, few data are available of biological variation in insulin secretion and action among individuals with T2D and MetS. The aim of this study was to explore the inter-individual variations using gold standard methods in a cross-sectional study of two independent cohorts of phenotypically well-characterized subjects. Cohort I included 486 subjects with MetS, and cohort II 62 subjects with established T2D. First phase insulin secretion was defined as the incremental area under the curve 0-8 min (iAUC_0-8 min) during an intravenous glucose tolerance test (IVGTT). Insulin sensitivity was measured as the insulin sensitivity index (S_I) modelled from IVGTT in cohort I, and in II as total glucose disposal (TGD) estimated from a euglycaemic-hyperinsulinaemic clamp. Variation is given as total range and, fold-variation between 5%- and 95%-percentile. The iAUC_0-8 min ranged from -60 to 3397 mUL^-1min^-1 among subjects with MetS and from -263 to 1194 mUL^-1min^-1 in subjects with T2D, representing a more than 10-fold variation. Insulin sensitivity ranged from S_I 0.19 to 15.29 (mU/L)^-1min^-1 among subjects with MetS and TGD 12.9-101.6 μmolkgFFM^-1min^-1 in subjects with T2D, representing a 6.8 and 5.5-fold variation, respectively. The other components of MetS; BMI, waist-hip ratio, HDL-cholesterol, triglycerides and blood pressure (BP), showed a 1.4-4.7-fold variation. In conclusion, our data demonstrated extensive inter-individual variations in insulin secretion and sensitivity. These variations may be essential to take into account when planning clinical research and treatment in subjects with T2D and MetS.

Latent Autoimmune Diabetes in Adults: A Review of Clinically Relevant Issues

Latent autoimmune diabetes in adults (LADA) is still a poorly characterized entity. However, its prevalence may be higher than that of classical type 1 diabetes. Patients with LADA are often misclassified as type 2 diabetes. The underlying autoimmune process against β-cell has important consequences for the prognosis, comorbidities, treatment choices and even patient-reported outcomes with this diabetes subtype. However, there is still an important gap of knowledge in many areas of clinical relevance. We are herein focusing on the state of knowledge of relevant clinical issues than may help in the diagnosis and management of subjects with LADA.

Obesity Does Not Modulate the Glycometabolic Benefit of Insoluble Cereal Fibre in Subjects with Prediabetes-A Stratified Post Hoc Analysis of the Optimal Fibre Trial (OptiFiT)

Obesity does not modulate the glycometabolic benefit of insoluble cereal fibre in subjects with prediabetes—a stratified post hoc analysis of the Optimal Fibre Trial (OptiFiT). Background: OptiFiT demonstrated the beneficial effect of insoluble oat fibres on dysglycemia in prediabetes. Recent analyses of OptiFiT and other randomised controlled trials (RCTs) indicated that this effect might be specific for the subgroup of patients with impaired fasting glucose (IFG). As subjects with IFG are more often obese, there is a need to clarify if the effect modulation is actually driven by glycemic state or body mass index (BMI). Aim: We conducted a stratified post hoc analysis of OptiFiT based on the presence or absence of obesity. Methods: 180 Caucasian participants with impaired glucose tolerance (IGT) were randomised in a double-blinded fashion to either twice-a-day fibre or placebo supplementation for 2 years (n = 89 and 91, respectively). Once a year, they underwent fasting blood sampling, an oral glucose tolerance test (oGTT) and full anthropometry. At baseline, out of 136 subjects who completed the first year of intervention, 87 (62%) were classified as OBESE (BMI >30) and 49 subjects were NONOBESE. We performed a stratified per-protocol analysis of the primary glycemic and secondary metabolic effects attributable to dietary fibre supplementation after 1 year of intervention. Results: Neither the NONOBESE nor the OBESE subgroup showed significant differences between the respective fibre and placebo groups in metabolic, anthropometric or inflammatory outcomes. None of the four subgroups showed a significant improvement in either fasting glucose or glycated haemoglobin (HbA1c) after 1 year of intervention and only OBESE fibre subjects improved 2 h glucose. Within the NONOBESE stratum, there were no significant differences in the change of primary or secondary metabolic parameters between the fibre and placebo arms. We found a significant interaction effect for leukocyte count (time × supplement × obesity status). Within the OBESE stratum, leukocyte count and gamma-glutamyl transferase (GGT) levels decreased more in the fibre group compared with placebo (adjusted for change in body weight). Comparison of both fibre groups revealed that OBESE subjects had a significantly stronger benefit with respect to leukocyte count and fasting C-peptide levels than NONOBESE participants. Only the effect on leukocyte count survived correction for multiple comparisons. In contrast, under placebo conditions, NONOBESE subjects managed to decrease their body fat content significantly more than OBESE ones. Intention-to-treat (ITT) analysis resulted in similar outcomes. Conclusions: The state of obesity does not relevantly modulate the beneficial effect of cereal fibre on major glycometabolic parameters by fibre supplementation, but leukocyte levels may be affected. Hence, BMI is not a suitable parameter to stratify this cohort with respect to diabetes risk or responsiveness to cereal fibre, but obesity needs to be accounted for when assessing anti-inflammatory effects of fibre treatments. Targeted diabetes prevention should focus on the actual metabolic state rather than on mere obesity.

Making sense of subclinical cardiac alterations in patients with diabetes

Patients with diabetes are prone to develop a distinct primary myocardial condition, diabetic cardiomyopathy, placing them at an increased risk for heart failure (1-3). This occurs independently of hypertension, coronary artery disease, and other established causes of heart failure. Pertinent findings include increased mass, concentric changes, and diastolic dysfunction of the left ventricle (4,5). Such adverse remodeling is common among patients with diabetes and appears to be strongly associated with its duration, suggesting a role for persistent metabolic stress (6-8). However, which exact components of the diabetic syndrome determine these cardiac alterations is not clear. Moreover, most studies have investigated patients with type 2 diabetes, and it is uncertain whether patients with type 1 diabetes experience similar myocardial changes. Continue reading full text in the preliminary PDF version.

Fasting Glucose State Determines Metabolic Response to Supplementation with Insoluble Cereal Fibre: A Secondary Analysis of the Optimal Fibre Trial (OptiFiT)

Background: High intake of cereal fibre is associated with reduced risk for type 2 diabetes and long-term complications. Within the first long-term randomized controlled trial specifically targeting cereal fibre, the Optimal Fibre Trial (OptiFiT), intake of insoluble oat fibre was shown to significantly reduce glycaemia. Previous studies suggested that this effect might be limited to subjects with impaired fasting glucose (IFG). Aim: We stratified the OptiFiT cohort for normal and impaired fasting glucose (NFG, IFG) and conducted a secondary analysis comparing the effects of fibre supplementation between these subgroups. Methods: 180 Caucasian participants with impaired glucose tolerance (IGT) were randomized to twice-a-day fibre or placebo supplementation for 2 years (n = 89 and 91, respectively), while assuring double-blinded intervention. Fasting blood sampling, oral glucose tolerance test and full anthropometry were assessed annually. At baseline, out of 136 subjects completing the first year of intervention, 72 (54%) showed IFG and IGT, while 64 subjects had IGT only (labelled “NFG”). Based on these two groups, we performed a stratified per-protocol analysis of glycometabolic and secondary effects during the first year of intervention. Results: The NFG group did not show significant differences between fibre and placebo group concerning anthropometric, glycometabolic, or other biochemical parameters. Within the IFG stratum, 2-h glucose, HbA1c, and gamma-glutamyl transferase levels decreased more in the fibre group, with a significant supplement x IFG interaction effect for HbA1c. Compared to NFG subjects, IFG subjects had larger benefits from fibre supplementation with respect to fasting glucose levels. Results were robust against adjustment for weight change and sex. An ITT analysis did not reveal any differences from the per-protocol analysis. Conclusions: Although stratification resulted in relatively small subgroups, we were able to pinpoint our previous findings from the entire cohort to the IFG subgroup. Cereal fibre can beneficially affect glycemic metabolism, with most pronounced or even isolated effectiveness in subjects with impaired fasting glucose.

Risk of diabetes-associated diseases in subgroups of patients with recent-onset diabetes: a 5-year follow-up study

BACKGROUND

Cluster analyses have proposed different diabetes phenotypes using age, BMI, glycaemia, homoeostasis model estimates, and islet autoantibodies. We tested whether comprehensive phenotyping validates and further characterises these clusters at diagnosis and whether relevant diabetes-related complications differ among these clusters, during 5-years of follow-up.

METHODS

Patients with newly diagnosed type 1 or type 2 diabetes in the German Diabetes Study underwent comprehensive phenotyping and assessment of laboratory variables. Insulin sensitivity was assessed using hyperinsulinaemic-euglycaemic clamps, hepatocellular lipid content using magnetic resonance spectroscopy, hepatic fibrosis using non-invasive scores, and peripheral and autonomic neuropathy using functional and clinical criteria. Patients were reassessed after 5 years. The German Diabetes Study is registered with ClinicalTrials.gov, number NCT01055093, and is ongoing.

FINDINGS

1105 patients were classified at baseline into five clusters, with 386 (35%) assigned to mild age-related diabetes (MARD), 323 (29%) to mild obesity-related diabetes (MOD), 247 (22%) to severe autoimmune diabetes (SAID), 121 (11%) to severe insulin-resistant diabetes (SIRD), and 28 (3%) to severe insulin-deficient diabetes (SIDD). At 5-year follow-up, 367 patients were reassessed, 128 (35%) with MARD, 106 (29%) with MOD, 88 (24%) with SAID, 35 (10%) with SIRD, and ten (3%) with SIDD. Whole-body insulin sensitivity was lowest in patients with SIRD at baseline (mean 4·3 mg/kg per min [SD 2·0]) compared with those with SAID (8·4 mg/kg per min [3·2]; p<0·0001), MARD (7·5 mg/kg per min [2·5]; p<0·0001), MOD (6·6 mg/kg per min [2·6]; p=0·0011), and SIDD (5·5 mg/kg per min [2·4]; p=0·0035). The fasting adipose-tissue insulin resistance index at baseline was highest in patients with SIRD (median 15·6 [IQR 9·3-20·9]) and MOD (11·6 [7·4-17·9]) compared with those with MARD (6·0 [3·9-10·3]; both p<0·0001) and SAID (6·0 [3·0-9·5]; both p<0·0001). In patients with newly diagnosed diabetes, hepatocellular lipid content was highest at baseline in patients assigned to the SIRD cluster (median 19% [IQR 11-22]) compared with all other clusters (7% [2-15] for MOD, p=0·00052; 5% [2-11] for MARD, p<0·0001; 2% [0-13] for SIDD, p=0·0083; and 1% [0-3] for SAID, p<0·0001), even after adjustments for baseline medication. Accordingly, hepatic fibrosis at 5-year follow-up was more prevalent in patients with SIRD (n=7 [26%]) than in patients with SAID (n=5 [7%], p=0·0011), MARD (n=12 [12%], p=0·012), MOD (n=13 [15%], p=0·050), and SIDD (n=0 [0%], p value not available). Confirmed diabetic sensorimotor polyneuropathy was more prevalent at baseline in patients with SIDD (n=9 [36%]) compared with patients with SAID (n=10 [5%], p<0·0001), MARD (n=39 [15%], p=0·00066), MOD (n=26 [11%], p<0·0001), and SIRD (n=10 [17%], p<0·0001).

INTERPRETATION

Cluster analysis can characterise cohorts with different degrees of whole-body and adipose-tissue insulin resistance. Specific diabetes clusters show different prevalence of diabetes complications at early stages of non-alcoholic fatty liver disease and diabetic neuropathy. These findings could help improve targeted prevention and treatment and enable precision medicine for diabetes and its comorbidities.

FUNDING

German Diabetes Center, German Federal Ministry of Health, Ministry of Culture and Science of the state of North Rhine-Westphalia, German Federal Ministry of Education and Research, German Diabetes Association, German Center for Diabetes Research, Research Network SFB 1116 of the German Research Foundation, and Schmutzler Stiftung.

Clinical phenotyping of newly diagnosed type 2 diabetes in Yemen

OBJECTIVE

To identify clinical phenotypes of type 2 diabetes (T2D) among adults presenting with a first diagnosis of diabetes.

RESEARCH DESIGN AND METHODS

A total of 500 consecutive patients were subject to clinical assessment and laboratory investigations. We used data-driven cluster analysis to identify phenotypes of T2D based on clinical variables and Homeostasis Model Assessment (HOMA2) of insulin sensitivity and beta-cell function estimated from paired fasting blood glucose and specific insulin levels.

RESULTS

The cluster analysis identified three statistically different clusters: cluster 1 (high insulin resistance and high beta-cell function group), which included patients with low insulin sensitivity and high beta-cell function; cluster 2 (low insulin resistance and low beta-cell function group), which included patients with high insulin sensitivity but very low beta-cell function; and cluster 3 (high insulin resistance and low beta-cell function group), which included patients with low insulin sensitivity and low beta-cell function. Insulin sensitivity, defined as median HOMA2-S, was progressively increasing from cluster 1 (35.4) to cluster 3 (40.9), to cluster 2 (76) (p<0.001). On the contrary, beta-cell function, defined as median HOMA2-β, was progressively declining from cluster 1 (78.3) to cluster 3 (30), to cluster 2 (22.3) (p<0.001). Clinical and biomarker variables associated with insulin resistance like obesity, abdominal adiposity, fatty liver, and high serum triglycerides were mainly seen in clusters 1 and 3. The highest median hemoglobin A1c value was noted in cluster 2 (88 mmol/mol) and the lowest in cluster 1.

CONCLUSION

Cluster analysis of newly diagnosed T2D in adults has identified three phenotypes based on clinical variables central to the development of diabetes and on specific clinical variables of each phenotype.