Aetiology of type 2 diabetes: an experimental medicine odyssey

This review describes a prolonged research endeavour to test the twin cycle hypothesis that type 2 diabetes is caused by fat-induced dysfunction of the liver and pancreas, guided by the happenstance of clinical practice. Testing of the personal fat threshold hypothesis, that individuals exhibit different levels of tolerance to intra-organ fat accumulation, is also described. Both hypotheses predict that type 2 diabetes is potentially reversible by weight loss. The results of the Counterpoint study supported the twin cycle hypothesis, leading to a second study which determined that short-duration diabetes was more likely to remit following the 10-15 kg weight loss. It also confirmed that remission was durable over 6 months on an isoenergetic, normal diet. Subsequently, it was shown that weight loss caused an immediate decrease of pancreas fat only in people with type 2 diabetes and also that postprandial incretin spikes after bariatric surgery had no role in normalising fasting plasma glucose. DiRECT, a 2 year randomised controlled study, demonstrated clinical utility, observing functional beta cell capacity to return almost to normal over 12 months. A small group of participants regained weight and redeveloped type 2 diabetes, allowing observation that the underlying pathophysiological mechanisms during onset of diabetes were as postulated by the twin cycle hypothesis. Major clinical benefit was demonstrated after a further 3 year follow-up in routine care, halving the incidence of serious adverse effect compared with the standard treatment control group. In answer to the question of whether individuals have a personal fat threshold for tolerance of fat, stepwise weight loss in people with type 2 diabetes and BMI in the range 21-27 kg/m2 resulted in remission in 70%, with a wide range of fat thresholds. Type 2 diabetes can be regarded as a condition of homogenous aetiology in genetically heterogenous individuals.

CT-derived adipose tissue characteristics and TAVI all-cause mortality and complications: a systematic review

Transcatheter Aortic Valve Implantation (TAVI) has revolutionized severe aortic stenosis treatment, but risk stratification remains challenging. This systematic review examined the association between computed tomography (CT)-derived adipose tissue parameters and TAVI outcomes. We searched major databases for studies on visceral (VAT), subcutaneous (SAT), and intramuscular (IMAT) adipose tissue parameters and post-TAVI outcomes. Fourteen studies (9692 patients) were included. Higher SAT area/volume was consistently associated with better survival (5 studies, HR range: 0.83-2.77, p < 0.05). Lower SAT and VAT density also correlated with better survival (5 and 4 studies, respectively, HR range: 1.31-1.46, p < 0.05). VAT area showed mixed results. A VAT:SAT ratio < 1 was associated with better cardiovascular outcomes in one study. Lower IMAT index correlated with shorter hospital stays in a single study. This review reveals complex relationships between adipose tissue parameters and TAVI outcomes. Lower adipose tissue density and higher subcutaneous adiposity were most consistently associated with better outcomes. These findings suggest that detailed analysis of adipose tissue characteristics may enhance risk stratification in TAVI candidates.

Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) Impacts Long-Term Outcomes After Curative-Intent Surgery for Hepatocellular Carcinoma

BACKGROUND

Curative surgery for hepatocellular carcinoma (HCC) includes liver resection (LR) and orthotopic liver transplantation (OLT). Due to the obesity epidemic, metabolic dysfunction-associated steatotic liver disease (MASLD) is a frequent HCC aetiology that often coincides with increased alcohol consumption, termed MetALD, or even alcohol-associated liver disease (ALD).

METHODS

Patients undergoing LR or OLT for HCC at Charité-Universitätsmedizin Berlin (2010-2020) were included in this retrospective cohort study investigating disease aetiology, time to recurrence (TTR), overall survival (OS) and CT-based body composition.

RESULTS

Out of 579 patients with HCC, 417 underwent LR and 162 OLT. Tumour aetiologies were viral n = 191 (33.0%), MASLD n = 158 (27.3%), MetALD n = 51 (8.8%), ALD n = 68 (11.7%) and other/cryptogenic n = 111 (19.2%). Patients with MASLD and MetALD had more intramuscular (p < 0.001, p = 0.015) and visceral fat (both p < 0.001) than patients with non-metabolic dysfunction aetiologies. Patients with MASLD-HCC had comparable TTR (median 26 months, [95% CI: 23-31] vs. 30 months [95% CI: 4-57], p = 0.425) but shorter OS than patients with other HCC aetiologies (63 months [95% CI: 42-84] vs. 80 months [95% CI: 60-100], hazard ratio: 1.53 [95% CI: 1.050-2.229], p = 0.026) after LR. Multivariate analysis confirmed MASLD aetiology, portal vein thrombosis and MELD score ≥ 10 as independent prognostic factors for OS in LR (adjusted p = 0.021,p < 0.001,p = 0.003), even after excluding in-hospital mortality (adjusted p = 0.016,p = 0.002,p = 0.002). Causes of death were similar in MASLD and non-MASLD aetiology.

CONCLUSIONS

Patients with HCC undergoing LR and meeting the new MASLD criteria have significantly shorter OS. This study provides empirical prognostic evidence for the novel MASLD/MetALD classification in a large European cohort of patients undergoing curative-intent HCC therapy.

The Twin Cycle Hypothesis of type 2 diabetes aetiology: From concept to national NHS programme

The development of magnetic resonance methods for quantifying intra-organ metabolites has permitted advances in the understanding of fasting and post-prandial carbohydrate and lipid handling in people with and without type 2 diabetes. Insulin resistance in the liver was shown to be related to excess intra-organ fat and was able to be returned to normal by weight loss. The practical effect of having muscle insulin sensitivity in the lower part of the wide normal range resulted in the obligatory shunting of carbohydrates via de novo lipogenesis into saturated fat. These observations provided the basis for the Twin Cycle Hypothesis of the aetiology of type 2 diabetes. Subsequent studies on people with type 2 diabetes confirmed the postulated pathophysiological abnormalities and demonstrated their reversibility by dietary weight loss of 10-15 kg. Overall, the fundamental understanding of the mechanisms causing type 2 diabetes has bridged physiological and clinical perspectives. Large population-based randomised controlled trials confirmed the practical clinical application of the method of achieving substantial weight loss, and an NHS programme is now in place offering potential remission to people within 6 years of diagnosis.

Lessons Learned From Epidemiology of Type 2 Diabetes in South Asians: Kelly West Award Lecture 2024

South Asia has high prevalence rates of type 2 diabetes (T2D). Until the 1990s, the prevalence of T2D within South Asia was low but much higher in the South Asian diaspora living abroad. Today, high prevalence rates of T2D are reported among those living in South Asia. T2D in South Asians presents with unique clinical features described as the "South Asian phenotype" that include younger age at onset of diabetes than in White Europeans, much lower BMI, hyperinsulinemia and greater insulin resistance, rapid decline in β-cell function resulting in low insulin reserve, low muscle mass, and greater ectopic fat deposition, especially in the liver. Also, prevalence of impaired fasting glucose is higher among South Asians than prevalence of impaired glucose tolerance. Genetic predisposition combined with intrauterine fetal programming (low vitamin B12 intake and high folate intake) increases susceptibility to T2D, from birth. In later life, overnutrition, especially a high carbohydrate intake with refined grains of higher glycemic index, coupled with low physical activity likely triggers the T2D epidemic in South Asians. Additionally, there are emerging risk factors like air pollution. Preventing T2D in South Asians requires a multifactorial approach, including improvements in maternal and fetal nutrition with special reference to vitamin B12 and folate intake, decreasing refined carbohydrate and increasing protein and fiber intake in the diet, increasing physical activity, and control of air pollution. Lessons learned from epidemiology of T2D in South Asians could be useful to other developing countries that are in earlier stages of epidemiological transition.

Adipocentric Strategy for the Treatment of Type 2 Diabetes Mellitus

The global prevalence of obesity and type 2 diabetes mellitus (T2D) has risen in parallel over recent decades. Most individuals diagnosed with T2D exhibit adiposopathy-related diabetes (ARD), a condition characterized by hyperglycemia accompanied by three core features: increased ectopic and visceral fat deposition, dysregulated adipokine secretion favoring a pro-inflammatory state, and insulin resistance. Despite advancements in precision medicine, international guidelines for T2D continue to prioritize individualized therapeutic approaches focused on glycemic control and complications, and many healthcare providers predominantly maintain a glucocentric strategy. This review advocates for an adipocentric treatment paradigm for most individuals with T2D, emphasizing the importance of prioritizing weight loss and visceral fat reduction as key drivers of therapeutic intensification. By combining lifestyle modifications with pharmacological agents that promote weight loss-including SGLT-2 inhibitors, GLP-1 receptor agonists, or dual GLP-1/GIP receptor agonists-and, when appropriate, metabolic surgery, this approach offers the potential for disease remission in patients with shorter disease duration. For others, it enables superior metabolic control compared to traditional glucose-centered strategies while simultaneously delivering cardiovascular and renal benefits. In conclusion, an adipocentric treatment framework for ARD, which represents the majority of T2D cases, effectively integrates glucocentric and cardio-nephrocentric goals. This approach constitutes the optimal strategy for ARD due to its efficacy in achieving disease remission, improving metabolic control, addressing obesity-related comorbidities, and reducing cardiovascular and renal morbidity and mortality.

Diabetes and obesity: leveraging heterogeneity for precision medicine

The increasing prevalence of diabetes, obesity, and their cardiometabolic sequelae present major global health challenges and highlight shortfalls of current approaches to the prevention and treatment of these conditions. Representing the largest global burden of morbidity and mortality, the pathobiological processes underlying cardiometabolic diseases are in principle preventable and, even when disease is manifest, sometimes reversable. Nevertheless, with current clinical and public health strategies, goals of widespread prevention and remission remain largely aspirational. Application of precision medicine approaches that reduce errors and improve accuracy in medical and health recommendations has potential to accelerate progress towards these goals. Precision medicine must also maintain safety and ideally be cost-effective, as well as being compatible with an individual's preferences, capabilities, and needs. Initial progress in precision medicine was made in the context of rare diseases, with much focus on pharmacogenetic studies, owing to the cause of these diseases often being attributable to highly penetrant single gene mutations. By contrast, most obesity and type 2 diabetes are heterogeneous in aetiology and clinical presentation, underpinned by complex interactions between genetic and non-genetic factors. The heterogeneity of these conditions can be leveraged for development of approaches for precision therapies. Adequate characterization of the heterogeneity in cardiometabolic disease necessitates diversity of and synthesis across data types and research methods, ideally culminating in precision trials and real-world application of precision medicine approaches. This State-of-the-Art Review provides an overview of the current state of the science of precision medicine, as well as outlining a roadmap for study designs that maximise opportunities and address challenges to clinical implementation of precision medicine approaches in obesity and diabetes.

Remission of type 2 diabetes mellitus: Emerging concepts and proposed diagnostic criteria

The remission of type 2 diabetes mellitus (T2DM) is a topic that has been widely discussed recently, and it gives new hope for people with T2DM. Achievement of normal blood glucose levels or levels below the diagnostic threshold for T2DM without pharmacotherapy among people with T2DM after metabolic surgery and carbohydrate or calorie-restricted diet paved the way for more enthusiastic research in this area. There is a lot of confusion regarding the appropriate terminology and definition of remission of T2DM. In this short review, we briefly analyzed the emerging concepts and proposed criteria for diagnosing remission of T2DM, which will be helpful for healthcare providers and people with T2DM.

The Causal Role of Ectopic Fat Deposition in the Pathogenesis of Metabolic Syndrome

Consuming a "modern" Western diet and overnutrition may increase insulin secretion. Additionally, nutrition-mediated hyperinsulinemia is a major driver of ectopic fat deposition. The global prevalence of metabolic syndrome is high and growing. Within this context, people with congenital lipodystrophy often experience a severe form of metabolic syndrome. Evidence is increasingly supporting that subtle partial lipodystrophy plays an important role in the development of metabolic syndrome in the general population. In individuals in the general population with subtle partial lipodystrophy, as well as in those with congenital lipodystrophy, the subcutaneous adipose tissues are unable to accommodate surplus energy intake. In both conditions, (excess) fat is directed toward the liver, pancreas, and muscles, where it is deposited as ectopic fat, as this fat can no longer be stored in the "safe" subcutaneous fat depots. Ectopic fat depositions cause insulin resistance in the liver and muscles, as well as β-cell dysfunction in the pancreas. Support of a direct pathological role of ectopic fat deposition in this condition is further provided by the rapid normalization of hepatic insulin sensitivity and improvement in pancreatic β-cell function after marked reductions in ectopic fat depositions. Thus, ectopic fat deposition in the liver, pancreas, and muscles may play a causal role in the pathogenesis of metabolic syndrome even in the general population. As such, the prevention of ectopic fat deposition may reduce the risk of metabolic syndrome and mitigate its effects.

A Novel and Comprehensive Wellness Assessment for Lifestyle-Based Interventions

Objective

While weight status and clinical laboratory measures are important in assessing obesity-related disease severity and chronic disease risk, including a broader range of emotional, psychosocial, and behavioral factors would provide greater context of an individual's overall state of wellness and could be used to better guide treatment decisions. The purpose of this research was to develop a comprehensive Lifestyle Wellness assessment for use in lifestyle-based wellness interventions and programs.

Methods

A cross-sectional exploratory factor analysis (EFA) was conducted using baseline data from N = 138 adults participating in behavioral weight loss trials. An unweighted least squares extraction method with oblique rotation was used. Twenty-one putative measures spanning constructs related to metabolic health, emotional health/wellbeing, body weight and composition, diet quality, and fitness were analyzed for retention.

Results

Mean body mass index (BMI) was 38.0 ± 6.6 kg/m2, mean age was 57.3 ± 11.1 years, and 77.5% of participants were female. The EFA produced a five-factor model with 13 items that explained 80.3% of the variance. The retained factors included: (1) Psychosocial State: mindfulness, resilience, quality of life, and happiness; (2) Blood Pressure State: systolic and diastolic blood pressure; (3) Lipid State: total cholesterol and LDL-cholesterol; (4) Fitness State: grip strength, jump height, and percent body fat; and (5) Body State: BMI and waist circumference.

Conclusions

Lifestyle Wellness is a comprehensive assessment that enables innovative wellness-related research such as metabolically healthy obese phenotypes and weight-neutral interventions. Future research should include investigations in additional populations with greater age, sex/gender, and body size diversity.

The vices and virtues of medical models of obesity

Despite numerous public health organizations supporting the pathologization of obesity and considering recent obesity rates a health crisis, many researchers in the humanities, social sciences, and even in the health sciences remain unconvinced. In this paper, we address a set of arguments coming from these academic fields that criticize medical models of obesity for their supposedly flawed diagnostic categories that shift focus onto individuals and support moralizing judgements. Clarifying some key claims in these models and explicating the view of obesity in terms of energy dysregulation, we aim to tease apart misunderstandings and argue that not only do these models not say what they are often accused of saying, but their apparent vices may actually be virtues in helping to combat stigma. Building on the social psychology of stigma and disease labeling, we then suggest that current medical models are largely supportive of many moral and political aims promoted by critics of these models.

Insulin receptor signalling in PDGFRβ-expressing cells influences systemic metabolism and negatively impacts lipid storage

Pericytes are vascular mural cells that support the microvasculature; their dysfunction contributes to diabetic retinopathy and has been linked to obesity in humans. To explore the role of pericyte insulin signalling on systemic metabolism we utilised male mice from our previously described PIR-/- (PIRKO) mouse line which has insulin receptor (Insr) knockout in PDGFRβ-expressing cells. These animals exhibit systemic insulin resistance from as early as 8-weeks of age, despite no change in body weight or activity level, and show altered body composition and hepatosteatosis. When challenged with high fat diet, PIR-/- remain insulin resistant but are protected from weight gain with reduced adipose tissue expansion across all depots and altered adipose morphology. Exhibiting parallels with the metabolically-obese-normal-weight (MONW) human phenotype, the PIR-/- line underlines the importance of pericyte biology in the development of both diabetes and obesity and establishes the angiopoietin (Ang)/Tie signalling pathway as a focus for future research.

Ethnic differences in the relationship between ectopic fat deposition and insulin sensitivity in Black African and White European men across a spectrum of glucose tolerance

AIM

To examine the hypothesis that there would be ethnic differences in the relationship between ectopic fat and tissue-specific insulin resistance (IR) across a spectrum of glucose tolerance in Black African (BA) and White European (WE) men.

MATERIALS AND METHODS

Fifty-three WE men (23/10/20 normal glucose tolerance [NGT]/impaired glucose tolerance [IGT]/type 2 diabetes [T2D]) and 48 BA men (20/10/18, respectively) underwent a two-step hyperinsulinaemic-euglycaemic clamp with infusion of D-[6,6-2H2]-glucose and [2H5]-glycerol to assess hepatic, peripheral and adipose tissue IR. Magnetic resonance imaging was used to measure subcutaneous adipose tissue, visceral adipose tissue (VAT) and intrahepatic lipid (IHL). Associations between ectopic fat and IR were assessed using linear regression models.

RESULTS

There were no differences in tissue-specific IR between ethnic groups at any stage of glucose tolerance. VAT level was consistently lower in the BA population; NGT (p = 0.013), IGT (p = 0.006) and T2D (p = 0.015). IHL was also lower in the BA compared with the WE men (p = 0.013). VAT and IHL levels were significantly associated with hepatic IR in the BA population (p = 0.001) and with peripheral IR in the WE population (p = 0.027).

CONCLUSIONS

The present study suggests that BA and WE men exhibit the same degree of IR across a glucose tolerance continuum, but with lower VAT and IHL levels in the BA population, suggesting that IR may be driven by a mechanism other than increased ectopic fat accumulation in BA men.

Investigation of the risk factors associated with prediabetes in normal-weight Qatari adults: a cross-sectional study

Type 2 diabetes is one of the most prevalent chronic diseases in the world, and more people than ever before have impaired glucose tolereance, or prediabetes. Many patients with impaired glucose tolerance and undiagnosed diabetes do not know that their glucose metabolism system has been in a state of disorder. Every year, about 5-10% of prediabetics develop diabetes. One of the important achieving factors may be the increase in blood lipids. However, it is not clear whether triglyceride is associated with impaired glucose tolerance and prediabetes in the Qatari population. Therefore, we investigated the relationship between the first several clinical variables and prediabetes status in normal and overweight populations. We conducted a cross-sectional study using data from the Qatar Biobank program. The study included 5,996 participants who were adults over the age of 20. We collected information about participants' fasting blood glucose levels with other clinical measurements and used various machine learning models and logistic regression to study the association between the clinical measurements and prediabetes for normal and overobese weight groups. The use of several machine learning models showed that, after adjusting the potential confounding factors such as age and sex, Triglyceride has been demonstrated to be positively correlated with prediabetes, and there was a special population dependence phenomenon. Among them, nonobese people (p < 0.05). The effect value and 95% confidence interval and OR of triglyceride on prediabetes was 2.79 and (e0.78, e1.28), respectively.

Discrepancy Between Genetically Predicted and Observed BMI Predicts Incident Type 2 Diabetes

OBJECTIVE

Obesity is a key predictor of type 2 diabetes (T2D). However, metabolic complications are not solely due to increased BMI. We hypothesized that differences between genetically predicted BMI and observed BMI (BMI-diff) could reflect deviation from individual set point and may predict incident T2D.

RESEARCH DESIGN AND METHODS

From the UK Biobank cohort, we selected participants of European ancestry without T2D (n = 332,154). The polygenic risk score for BMI was calculated via Bayesian regression and continuous shrinkage priors (PRS-CS). According to the BMI-diff, the 10-year risk of T2D was assessed using multivariable Cox proportional hazards model. Independent data from the Korean Genome and Epidemiology Study (KoGES) cohort from South Korea (n = 7,430) were used for replication.

RESULTS

Participants from the UK Biobank were divided into train (n = 268,041) and test set (n = 115,119) to establish genetically predicted BMI. In the test set, the genetically predicted BMI explained 7.1% of the variance of BMI, and there were 3,599 T2D cases (3.1%) during a 10-year follow-up. Participants in the higher quintiles of BMI-diff (more obese than genetically predicted) had significantly higher risk of T2D than those in the lowest quintile after adjusting for observed BMI: the adjusted hazard ratio of the 1st quintile (vs. 5th quintile) was 1.61 (95% CI 1.26-2.05, P < 0.001). Results were consistent among individuals in the KoGES study. Moreover, higher BMI than predicted was associated with impaired insulin sensitivity.

CONCLUSIONS

Having a higher BMI than genetically predicted is associated with an increased risk of T2D. These findings underscore the potential to reassess T2D risk based on individual levels of obesity using genetic thresholds for BMI.

Preserving insulin function in diabetes: a case report

BACKGROUND

This case report explores the long-term dynamics of insulin secretion and glycemic control in two patients with diabetes mellitus type 2 over 20 years. The observations underscore the impact of lifestyle interventions, including weight loss and calorie restriction, on insulin secretion patterns and glucose levels during 75 g oral glucose tolerance tests. Additionally, the role of hemoglobin A1c fluctuations, influenced by various factors such as body weight, exercise, and pharmacological interventions, is investigated.

CASE PRESENTATION

Case 1 involves a Japanese woman now in her late 70s who successfully maintained her hemoglobin A1c below 7% for over two decades through sustained weight loss and lifestyle changes. Despite a gradual decline in the homeostasis model assessment of β cell function, the patient exhibited remarkable preservation of insulin secretion patterns over the 20-year follow-up. In case 2, a Japanese woman, now in her early 70s, experienced an improvement in hemoglobin A1c to 6.3% after a period of calorie limitation due to a wrist fracture in 2018. This incident seemed to trigger a temporary rescue of pancreatic β cell function, emphasizing the dynamic nature of insulin secretion. Both cases highlight the potential for pancreatic β cell rescue and underscore the persistence of insulin secretion over the 20-year follow-up. Additionally, we have briefly discussed three additional cases with follow-ups ranging from 10 to 17 years, demonstrating similar trends in glucose and insulin ratios.

CONCLUSIONS

Long-term lifestyle interventions, such as weight loss and calorie restriction, can preserve pancreatic β cell function and maintain glycemic control in type 2 diabetes patients over 20 years. Two patients showed stable or improved insulin secretion and favorable hemoglobin A1c levels, challenging the traditional view of irreversible β cell decline. The findings highlight the importance of personalized, nonpharmacological approaches, suggesting that sustained lifestyle changes can significantly impact diabetes management and potentially rescue β cell function.

Understanding the cause of type 2 diabetes

Type 2 diabetes has long been thought to have heterogenous causes, even though epidemiological studies uniformly show a tight relationship with overnutrition. The twin cycle hypothesis postulated that interaction of self-reinforcing cycles of fat accumulation inside the liver and pancreas, driven by modest but chronic positive calorie balance, could explain the development of type 2 diabetes. This hypothesis predicted that substantial weight loss would bring about a return to the non-diabetic state, permitting observation of the pathophysiology determining the transition. These changes were postulated to reflect the basic mechanisms of causation in reverse. A series of studies over the past 15 years has elucidated these underlying mechanisms. Together with other research, the interaction of environmental and genetic factors has been clarified. This knowledge has led to successful implementation of a national programme for remission of type 2 diabetes. This Review discusses the paucity of evidence for heterogeneity in causes of type 2 diabetes and summarises the in vivo pathophysiological changes, which cause this disease of overnutrition. Type 2 diabetes has a homogenous cause expressed in genetically heterogenous individuals.

The Elusive Nature of ABCC8-related Maturity-Onset Diabetes of the Young (ABCC8-MODY). A Review of the Literature and Case Discussion

PURPOSE OF REVIEW

Maturity-onset diabetes of the young (MODY) are monogenic forms of diabetes resulting from genetic defects, usually transmitted in an autosomal dominant fashion, leading to β-cell dysfunction. Due to the lack of homogeneous clinical features and univocal diagnostic criteria, MODY is often misdiagnosed as type 1 or type 2 diabetes, hence its diagnosis relies mostly on genetic testing. Fourteen subtypes of MODY have been described to date. Here, we review ABCC8-MODY pathophysiology, genetic and clinical features, and current therapeutic options.

RECENT FINDINGS

ABCC8-MODY is caused by mutations in the adenosine triphosphate (ATP)-binding cassette transporter subfamily C member 8 (ABCC8) gene, involved in the regulation of insulin secretion. The complexity of ABCC8-MODY genetic picture is mirrored by a variety of clinical manifestations, encompassing a wide spectrum of disease severity. Such inconsistency of genotype-phenotype correlation has not been fully understood. A correct diagnosis is crucial for the choice of adequate treatment and outcome improvement. By targeting the defective gene product, sulfonylureas are the preferred medications in ABCC8-MODY, although efficacy vary substantially. We illustrate three case reports in whom a diagnosis of ABCC8-MODY was suspected after the identification of novel ABCC8 variants that turned out to be of unknown significance. We discuss that careful interpretation of genetic testing is needed even on the background of a suggestive clinical context. We highlight the need for further research to unravel ABCC8-MODY disease mechanisms, as well as to clarify the pathogenicity of identified ABCC8 variants and their influence on clinical presentation and response to therapy.

Body Size Measurements Grouped Independently of Common Clinical Measures of Metabolic Health: An Exploratory Factor Analysis

BACKGROUND

Obesity is commonly aggregated with indices of metabolic health. Proponents of body positivity approaches question whether body size is a determinant of health and well-being. Our objective was to conduct an exploratory factor analysis (EFA) to determine if body size measurements factor load with or independent of metabolic health measures.

METHODS

The EFA was conducted on n= 249 adults using baseline data from four weight loss trials (Sample 1: n = 40; Sample 2: n = 52; Sample 3: n = 53; Sample 4: n = 104). An EFA of nine items (systolic blood pressure [SBP], diastolic blood pressure [DBP], hemoglobin A1c [HbA1c], HDL-cholesterol [HDL], LDL-cholesterol [LDL], total cholesterol [TC], body mass index [BMI], body fat percent BF%], and waist circumference [WC]) was conducted with oblique rotation.

RESULTS

Three factors were retained, which produced a model explaining 87.5% of the variance. Six items loaded strongly (>0.8) under three components and were selected for retention (Factor 1: LDL and TC; Factor 2: BMI and WC; Factor 3: SBP and DBP).

CONCLUSION

Body size measures loaded separately from measures of metabolic health and metabolic health were further split into lipid- and blood pressure-focused factors. These results support weight-neutral interventions to improve overall health and well-being.

Overnutrition, Hyperinsulinemia and Ectopic Fat: It Is Time for A Paradigm Shift in the Management of Type 2 Diabetes

The worldwide incidence of prediabetes/type 2 has continued to rise the last 40 years. In the same period, the mean daily energy intake has increased, and the quality of food has significantly changed. The chronic exposure of pancreatic β-cells to calorie excess (excessive energy intake) and food additives may increase pancreatic insulin secretion, decrease insulin pulses and/or reduce hepatic insulin clearance, thereby causing chronic hyperinsulinemia and peripheral insulin resistance. Chronic calorie excess and hyperinsulinemia may promote lipogenesis, inhibit lipolysis and increase lipid storage in adipocytes. In addition, calorie excess and hyperinsulinemia can induce insulin resistance and contribute to progressive and excessive ectopic fat accumulation in the liver and pancreas by the conversion of excess calories into fat. The personal fat threshold hypothesis proposes that in susceptible individuals, excessive ectopic fat accumulation may eventually lead to hepatic insulin receptor resistance, the loss of pancreatic insulin secretion, hyperglycemia and the development of frank type 2 diabetes. Thus, type 2 diabetes seems (partly) to be caused by hyperinsulinemia-induced excess ectopic fat accumulation in the liver and pancreas. Increasing evidence further shows that interventions (hypocaloric diet and/or bariatric surgery), which remove ectopic fat in the liver and pancreas by introducing a negative energy balance, can normalize insulin secretion and glucose tolerance and induce the sustained biochemical remission of type 2 diabetes. This pathophysiological insight may have major implications and may cause a paradigm shift in the management of type 2 diabetes: avoiding/reducing ectopic fat accumulation in the liver and pancreas may both be essential to prevent and cure type 2 diabetes.

Weight loss treatment for COVID-19 in patients with NCDs: a pilot prospective clinical trial

COVID-19 comorbid with noncommunicable chronic diseases (NCDs) complicates the diagnosis, treatment, and prognosis, and increases the mortality rate. The aim is to evaluate the effects of a restricted diet on clinical/laboratory inflammation and metabolic profile, reactive oxygen species (ROS), and body composition in patients with COVID-19 comorbid with NCDs. We conducted a 6-week open, pilot prospective controlled clinical trial. The study included 70 adult patients with COVID-19 comorbid with type 2 diabetes (T2D), hypertension, or nonalcoholic steatohepatitis (NASH).

INTERVENTIONS

a restricted diet including calorie restriction, hot water drinking, walking, and sexual self-restraint.

PRIMARY ENDPOINTS

COVID-19 diagnosis by detecting SARS-CoV-2 genome by RT-PCR; weight loss in Main group; body temperature; C-reactive protein. Secondary endpoints: the number of white blood cells; erythrocyte sedimentation rate; adverse effects during treatment; fasting blood glucose, glycosylated hemoglobin A1c (HbA1c), systolic/diastolic blood pressure (BP); blood lipids; ALT/AST, chest CT-scan. In Main group, patients with overweight lost weight from baseline (- 12.4%; P < 0.0001); 2.9% in Main group and 7.2% in Controls were positive for COVID-19 (RR: 0.41, CI: 0.04-4.31; P = 0.22) on the 14th day of treatment. Body temperature and C-reactive protein decreased significantly in Main group compared to Controls on day 14th of treatment (P < 0.025). Systolic/diastolic BP normalized (P < 0.025), glucose/lipids metabolism (P < 0.025); ALT/AST normalized (P < 0.025), platelets increased from baseline (P < 0.025), chest CT (P < 0.025) in Main group at 14 day of treatment. The previous antidiabetic, antihypertensive, anti-inflammatory, hepatoprotective, and other symptomatic medications were adequately decreased to completely stop during the weight loss treatment. Thus, the fast weight loss treatment may be beneficial for the COVID-19 patients with comorbid T2D, hypertension, and NASH over traditional medical treatment because, it improved clinical and laboratory/instrumental data on inflammation; glucose/lipid metabolism, systolic/diastolic BPs, and NASH biochemical outcomes, reactive oxygen species; and allowed patients to stop taking medications.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05635539 (02/12/2022): https://clinicaltrials.gov/ct2/show/NCT05635539?term=NCT05635539&draw=2&rank=1 .

Increased skeletal muscle mass index was involved in glycemic efficacy following diabetes treatment, and changes in fat mass index correlated with the changes in the lipid ratio in type 2 diabetes

AIM

This study aimed to investigate the association between changes in body composition, glycated hemoglobin, and lipid ratio during the treatment of patients with type 2 diabetes mellitus (T2DM).

METHODS

This retrospective analysis used data from outpatients with T2DM who had confirmed body composition and measured laboratories at administration and after treatment. The baseline characteristics and prescribed treatment were collected. The total cholesterol/high-density lipoprotein cholesterol (HDL) ratio, low-density lipoprotein cholesterol (LDL)/HDL ratio, and triglyceride-glucose (TyG) index were also calculated.

RESULTS

A total of 207 patients (mean patient age, 62.0 ± 13.7 years; 68.1 % males) were enrolled. Fat mass index (FMI) changes correlated with the changes in the lipid ratio, whereas skeletal muscle mass index (SMI) changes inversely correlated with glycated hemoglobin (HbA1c) changes. Multiple regression analysis showed that changes in LDL/HDL and TyG correlated with FMI changes (t = 2.388, p = 0.017, t = 2.022, p = 0.044). Conversely, HbA1c changes correlated with SMI changes (t = -2.552, p = 0.011).

CONCLUSION

In patients with T2DM, increased SMI was involved in glycemic efficacy, and FMI changes were associated with LDL/HDL and TyG.

Practice effects of personalized interventions with interdisciplinary teamwork in type 2 diabetes remission: a retrospective study

Objectives

A retrospective analysis of the clinical outcomes of personalized interventions for type 2 diabetes mellitus (T2DM) in an interdisciplinary team.

Methods

Under the guidance of an interdisciplinary team, 40 patients with T2DM underwent a systematic examination at the beginning of the intervention, 3 months after the intervention, and 3 months of follow-up at the end of the intervention (i.e., at 6 months). Key indicators such as fasting plasma glucose (FPG), 2-hour postprandial glucose (2hPG), fasting insulin level (FINS), glycated hemoglobin (HbA1c), blood lipids, and body mass index (BMI) were measured.

Results

After the 3-month intervention, participants' BMI, FPG, 2hPG, FINS, and HbA1c improved significantly, with statistically significant differences (P<0.05).These metrics remained essentially stable at the 3-month follow-up. Of all the participants, 92.5% (37 cases in total) successfully discontinued their medication after 3 months of intervention, of which 80% (32 cases) remained stable during the 3-month follow-up after discontinuation, fulfilling the criteria for remission of T2DM; 2 cases successfully reduced the dose of their medication, and only 1 case was maintained on the original treatment.

Conclusions

Through an interdisciplinary team intervention strategy, we significantly optimized the glucose metabolism, lipid metabolism, and BMI status of patients with T2DM, making diabetes remission an achievable goal, which provides valuable experience for further optimization of diabetes prevention and control protocols.

Modelling remission from overweight type 2 diabetes reveals how altering advice may counter relapse

The development or remission of diet-induced overweight type 2 diabetes involves many biological changes which occur over very different timescales. Remission, defined by HbA1c<6.5%, or fasting plasma glucose concentration G<126 mg/dl, may be achieved rapidly by following weight loss guidelines. However, remission is often short-term, followed by relapse. Mathematical modelling provides a way of investigating a typical situation, in which patients are advised to lose weight and then maintain fat mass, a slow variable. Remission followed by relapse, in a modelling sense, is equivalent to changing from a remission trajectory with steady state G<126 mg/dl, to a relapse trajectory with steady state G≥126 mg/dl. Modelling predicts that a trajectory which maintains weight will be a relapse trajectory, if the fat mass chosen is too high, the threshold being dependent on the lipid to carbohydrate ratio of the diet. Modelling takes into account the effects of hepatic and pancreatic lipid on hepatic insulin sensitivity and β-cell function, respectively. This study leads to the suggestion that type 2 diabetes remission guidelines be given in terms of model parameters, not variables; that is, the patient should adhere to a given nutrition and exercise plan, rather than achieve a certain subset of variable values. The model predicts that calorie restriction, not weight loss, initiates remission from type 2 diabetes; and that advice of the form 'adhere to the diet and exercise plan' rather than 'achieve a certain weight loss' may help counter relapse.

Role of epicardial adipose tissue in diabetic cardiomyopathy through the lens of cardiovascular magnetic resonance imaging - a narrative review

Accumulating evidence suggests that ectopic/visceral adiposity may play a key role in the pathogenesis of nonischaemic cardiovascular diseases associated with type 2 diabetes. Epicardial adipose tissue (EAT) is a complex visceral fat depot, covering 80% of the cardiac surface with anatomical and functional contiguity to the myocardium and coronary arteries. EAT interacts with the biology of the underlying myocardium by secreting a wide range of adipokines. Magnetic resonance imaging (MRI) is the reference modality for structural and functional imaging of the heart. The technique is now also emerging as the reference imaging modality for EAT quantification. With this narrative review, we (a) surveyed contemporary clinical studies that utilized cardiovascular MRI to characterize EAT (studies published 2010-2023); (b) listed the clinical trials monitoring the response to treatment in EAT size as well as myocardial functional and structural parameters and (c) discussed the potential pathophysiological role of EAT in the development of diabetic cardiomyopathy. We concluded that increased EAT quantity and its inflammatory phenotype correlate with early signs of left ventricle dysfunction and may have a role in the pathogenesis of cardiac disease in diabetes with and without coronary artery disease.

Very low calorie diets and total diet replacement in type 2 diabetes: where are we now?

Management of type 2 diabetes has now been simplified by the understanding that the condition is caused by excess fat in the liver together with suppression of beta cell function by the associated excess liver export of fat. These factors can be reversed by substantial weight loss leading to remission in the early years after diagnosis, or at least major decrease in cardiovascular risks and improvement in glucose control for all. Weight loss by any means is successful, but it is most easily achieved by rapid action using a low or very low calorie diet of around 800 kcal/day followed by sustained modest restraint of dietary habits. Oral hypoglycaemic agents and one antihypertensive drug can be withdrawn on day 1 of the weight loss diet, raising the importance of appropriate deprescribing.

The Metabolic Syndrome, a Human Disease

This review focuses on the question of metabolic syndrome (MS) being a complex, but essentially monophyletic, galaxy of associated diseases/disorders, or just a syndrome of related but rather independent pathologies. The human nature of MS (its exceptionality in Nature and its close interdependence with human action and evolution) is presented and discussed. The text also describes the close interdependence of its components, with special emphasis on the description of their interrelations (including their syndromic development and recruitment), as well as their consequences upon energy handling and partition. The main theories on MS's origin and development are presented in relation to hepatic steatosis, type 2 diabetes, and obesity, but encompass most of the MS components described so far. The differential effects of sex and its biological consequences are considered under the light of human social needs and evolution, which are also directly related to MS epidemiology, severity, and relations with senescence. The triggering and maintenance factors of MS are discussed, with especial emphasis on inflammation, a complex process affecting different levels of organization and which is a critical element for MS development. Inflammation is also related to the operation of connective tissue (including the adipose organ) and the widely studied and acknowledged influence of diet. The role of diet composition, including the transcendence of the anaplerotic maintenance of the Krebs cycle from dietary amino acid supply (and its timing), is developed in the context of testosterone and β-estradiol control of the insulin-glycaemia hepatic core system of carbohydrate-triacylglycerol energy handling. The high probability of MS acting as a unique complex biological control system (essentially monophyletic) is presented, together with additional perspectives/considerations on the treatment of this 'very' human disease.

Heat shock response during the resolution of inflammation and its progressive suppression in chronic-degenerative inflammatory diseases

The heat shock response (HSR) is a crucial biochemical pathway that orchestrates the resolution of inflammation, primarily under proteotoxic stress conditions. This process hinges on the upregulation of heat shock proteins (HSPs) and other chaperones, notably the 70 kDa family of heat shock proteins, under the command of the heat shock transcription factor-1. However, in the context of chronic degenerative disorders characterized by persistent low-grade inflammation (such as insulin resistance, obesity, type 2 diabetes, nonalcoholic fatty liver disease, and cardiovascular diseases) a gradual suppression of the HSR does occur. This work delves into the mechanisms behind this phenomenon. It explores how the Western diet and sedentary lifestyle, culminating in the endoplasmic reticulum stress within adipose tissue cells, trigger a cascade of events. This cascade includes the unfolded protein response and activation of the NOD-like receptor pyrin domain-containing protein-3 inflammasome, leading to the emergence of the senescence-associated secretory phenotype and the propagation of inflammation throughout the body. Notably, the activation of the NOD-like receptor pyrin domain-containing protein-3 inflammasome not only fuels inflammation but also sabotages the HSR by degrading human antigen R, a crucial mRNA-binding protein responsible for maintaining heat shock transcription factor-1 mRNA expression and stability on heat shock gene promoters. This paper underscores the imperative need to comprehend how chronic inflammation stifles the HSR and the clinical significance of evaluating the HSR using cost-effective and accessible tools. Such understanding is pivotal in the development of innovative strategies aimed at the prevention and treatment of these chronic inflammatory ailments, which continue to take a heavy toll on global health and well-being.

Does a Ketogenic Diet Have a Place Within Diabetes Clinical Practice? Review of Current Evidence and Controversies

Carbohydrate restriction has gained increasing popularity as an adjunctive nutritional therapy for diabetes management. However, controversy remains regarding the long-term suitability, safety, efficacy and potential superiority of a very low carbohydrate, ketogenic diet compared to current recommended nutritional approaches for diabetes management. Recommendations with respect to a ketogenic diet in clinical practice are often hindered by the lack of established definition, which prevents its capacity to be most appropriately prescribed as a therapeutic option for diabetes. Furthermore, with conflicted evidence, this has led to uncertainty amongst clinicians on how best to support and advise their patients. This review will explore whether a ketogenic diet has a place within clinical practice by reviewing current evidence and controversies.

Whole Blood-based Transcriptional Risk Score for Nonobese Type 2 Diabetes Predicts Dynamic Changes in Glucose Metabolism

CONTEXT

The performance of peripheral blood transcriptional markers in evaluating risk of type 2 diabetes (T2D) with normal body mass index (BMI) is unknown.

OBJECTIVE

We developed a whole blood-based transcriptional risk score (wb-TRS) for nonobese T2D and assessed its contributions on disease risk and dynamic changes in glucose metabolism.

METHODS

Using a community-based cohort with blood transcriptome data, we developed the wb-TRS in 1105 participants aged ≥40 years who maintained a normal BMI for up to 10 years, and we validated the wb-TRS in an external dataset. Potential biological significance was explored.

RESULTS

The wb-TRS included 144 gene transcripts. Compared to the lowest tertile, wb-TRS in tertile 3 was associated with 8.91-fold (95% CI, 3.53-22.5) higher risk and each 1-unit increment was associated with 2.63-fold (95% CI, 1.87-3.68) higher risk of nonobese T2D. Furthermore, baseline wb-TRS significantly associated with dynamic changes in average, daytime, nighttime, and 24-hour glucose, HbA1c values, and area under the curve of glucose measured by continuous glucose monitoring over 6 months of intervention. The wb-TRS improved the prediction performance for nonobese T2D, combined with fasting glucose, triglycerides, and demographic and anthropometric parameters. Multi-contrast gene set enrichment (Mitch) analysis implicated oxidative phosphorylation, mTORC1 signaling, and cholesterol metabolism involved in nonobese T2D pathogenesis.

CONCLUSION

A whole blood-based nonobese T2D-associated transcriptional risk score was validated to predict dynamic changes in glucose metabolism. These findings suggested several biological pathways involved in the pathogenesis of nonobese T2D.

Disentangling Dual Threats: Premature Coronary Artery Disease and Early-Onset Type 2 Diabetes Mellitus in South Asians

South Asian individuals (SAs) face heightened risks of premature coronary artery disease (CAD) and early-onset type 2 diabetes mellitus (T2DM), with grave health, societal, and economic implications due to the region's dense population. Both conditions, influenced by cardiometabolic risk factors such as insulin resistance, hypertension, and central adiposity, manifest earlier and with unique thresholds in SAs. Epidemiological, demographic, nutritional, environmental, sociocultural, and economic transitions in SA have exacerbated the twin epidemic. The coupling of premature CAD and T2DM arises from increased obesity due to limited adipose storage, early-life undernutrition, distinct fat thresholds, reduced muscle mass, and a predisposition for hepatic fat accumulation from certain dietary choices cumulatively precipitating a decline in insulin sensitivity. As T2DM ensues, the β-cell adaptive responses are suboptimal, precipitating a transition from compensatory hyperinsulinemia to β-cell decompensation, underscoring a reduced functional β-cell reserve in SAs. This review delves into the interplay of these mechanisms and highlights a prediabetes endotype tied to elevated vascular risk. Deciphering these mechanistic interconnections promises to refine stratification paradigms, surpassing extant risk-prediction strategies.

Attendance, Weight Loss, and Participation in a Behavioural Diabetes Prevention Programme

BACKGROUND

Weight loss in diabetes prevention programmes has been shown to be associated with participants' age, socio-economic status, and ethnicity. However, little is known about how these differences relate to attendance and whether such differences can be mediated by other potentially modifiable factors. Differential effectiveness across these factors may exacerbate health inequalities.

METHOD

Prospective analysis of participant data collected by one provider of the standardised national NHS diabetes prevention programme in England. Mediation analysis was performed via a structural equation model to examine whether the number of attended sessions mediated the associations of age, socio-economic status, and ethnicity with follow-up weight. The group-level factor of number of attended sessions was examined using multiple linear regression as a benchmark; multilevel linear regression using three levels (venue, coach, and group); and fixed effects regression to account for venue-specific and coach-specific characteristics.

RESULTS

The associations of age, socio-economic status, and ethnicity with follow-up weight were all mediated by the number of attended sessions. Group size was associated with attendance in an inverted 'U' shape, and the number of days between referral and group start was negatively associated with attendance. Time of day, day of the week, and the number of past groups led by the coach were not associated with attendance.

CONCLUSION

Most of the differences in weight loss initially attributed to socio-demographic factors are mediated by the attendance of the diabetes prevention programme. Therefore, targeted efforts to improve uptake and adherence to such programmes may help alleviate inequalities.

Aetiology of Type 2 diabetes in people with a 'normal' body mass index: testing the personal fat threshold hypothesis

Weight loss in overweight or obese individuals with Type 2 diabetes (T2D) can normalize hepatic fat metabolism, decrease fatty acid oversupply to β cells and restore normoglycaemia. One in six people has BMI <27 kg/m2 at diagnosis, and their T2D is assumed to have different aetiology. The Personal Fat Threshold hypothesis postulated differing individual thresholds for lipid overspill and adverse effects on β-cell function. To test this hypothesis, people with Type 2 diabetes and body mass index <27kg/m2 (n = 20) underwent repeated 5% weight loss cycles. Metabolic assessments were carried out at stable weight after each cycle and after 12 months. To determine how closely metabolic features returned to normal, 20 matched normoglycemic controls were studied once. Between baseline and 12 months: BMI fell (mean ± SD), 24.8 ± 0.4 to 22.5 ± 0.4 kg/m2 (P<0.0001) (controls: 21.5 ± 0.5); total body fat, 32.1 ± 1.5 to 27.6 ± 1.8% (P<0.0001) (24.6 ± 1.5). Liver fat content and fat export fell to normal as did fasting plasma insulin. Post-meal insulin secretion increased but remained subnormal. Sustained diabetes remission (HbA1c < 48 mmol/mol off all glucose-lowering agents) was achieved by 70% (14/20) by initial weight loss of 6.5 (5.5-10.2)%. Correction of concealed excess intra-hepatic fat reduced hepatic fat export, with recovery of β-cell function, glycaemic improvement in all and return to a non-diabetic metabolic state in the majority of this group with BMI <27 kg/m2 as previously demonstrated for overweight or obese groups. The data confirm the Personal Fat Threshold hypothesis: aetiology of Type 2 diabetes does not depend on BMI. This pathophysiological insight has major implications for management.

Assessment of obesity

Obesity is a chronic, progressive and relapsing disease, characterised by the presence of abnormal or excess adiposity that impairs health and social wellbeing. It is associated with obesity-related disease complications, health inequalities and premature death. Clinical evaluation of obesity requires a thorough history and examination. Assessment should focus not only on anthropometric measurements, but also on the mental, metabolic, mechanical and monetary impact of adiposity, including multiple health conditions. Increased awareness and knowledge will help reduce weight stigma and biases. A focused non-judgemental assessment will help guide further investigations, timely referral and management.

Role of Epicardial Adipose Tissue Secretome on Cardiovascular Diseases

Obesity and insulin resistance are associated with the inflamed and defective adipose tissue (AT) phenotype, and are established risk factors for cardiovascular diseases (CVDs). Extracellular vesicles (EVs) are a heterogeneous group of cell-derived lipid membrane vesicles involved in the onset and development of many pathologies, including insulin resistance, diabetes, and CVDs. The inflammation associated with overweight and obesity triggers the transition of the AT secretome from healthy to pathological, with a consequent increased expression of pro-inflammatory mediators. Epicardial adipose tissue (EAT) is a specialized fat depot that surrounds the heart, in direct contact with the myocardium. Recently, the role of EAT in regulating the physiopathology of many heart diseases has been increasingly explored. In particular, the EAT phenotype and derived EVs have been associated with the onset and exacerbation of CVDs. In this review, we will focus on the role of the AT secretome in the case of CVDs, and will discuss the beneficial effects of EVs released by AT as promising therapeutic candidates.

Special Population: Lean Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is strongly associated with obesity but around 10% to 20% of patients with NAFLD have normal body mass index, a condition referred to as lean or nonobese NAFLD. Although lean patients more often have milder liver disease, a proportion may nonetheless develop steatohepatitis and advanced liver fibrosis. Both genetic and environmental factors contribute to the development of NAFLD. Noninvasive tests have similarly good accuracy as initial assessments for lean NAFLD. Future studies should determine the most appropriate treatment in this special population.

Non-Alcoholic Fatty Liver Disease or Type 2 Diabetes Mellitus—The Chicken or the Egg Dilemma

In clinical practice, we often deal with patients who suffer from non-alcoholic fatty liver disease (NAFLD) concurrent with type 2 diabetes mellitus (T2DM). The etiopathogenesis of NAFLD is mainly connected with insulin resistance (IR) and obesity. Similarly, the latter patients are in the process of developing T2DM. However, the mechanisms of NAFLD and T2DM coexistence have not been fully elucidated. Considering that both diseases and their complications are of epidemic proportions and significantly affect the length and quality of life, we aimed to answer which of these diseases appears first and thereby highlight the need for their diagnosis and treatment. To address this question, we present and discuss the epidemiological data, diagnoses, complications and pathomechanisms of these two coexisting metabolic diseases. This question is difficult to answer due to the lack of a uniform procedure for NAFLD diagnosis and the asymptomatic nature of both diseases, especially at their beginning stages. To conclude, most researchers suggest that NAFLD appears as the first disease and starts the sequence of circumstances leading ultimately to the development of T2DM. However, there are also data suggesting that T2DM develops before NAFLD. Despite the fact that we cannot definitively answer this question, it is very important to bring the attention of clinicians and researchers to the coexistence of NAFLD and T2DM in order to prevent their consequences.

White Adipose Tissue Dysfunction: Pathophysiology and Emergent Measurements

White adipose tissue (AT) dysfunction plays an important role in the development of cardiometabolic alterations associated with obesity. AT dysfunction is characterized by the loss of the expansion capacity of the AT, an increment in adipocyte hypertrophy, and changes in the secretion profile of adipose cells, associated with accumulation of macrophages and inflammation. Since not all people with an excess of adiposity develop comorbidities, it is necessary to find simple tools that can evidence AT dysfunction and allow the detection of those people with the potential to develop metabolic alterations. This review focuses on the current pathophysiological mechanisms of white AT dysfunction and emerging measurements to assess its functionality.

A healthful plant-based eating pattern is longitudinally associated with higher insulin sensitivity in Australian adults

BACKGROUND

A healthful plant-based eating pattern is associated with lower type 2 diabetes risk; however, the association with its preceding state, compromised insulin sensitivity, is less well-established, particularly in younger populations with repeated measures of diet over time.

OBJECTIVE

We aimed to examine the longitudinal relationship between a healthful plant-based eating pattern and insulin sensitivity in young to middle-aged adults.

METHODS

We included 667 participants from the Childhood Determinants of Adult Health (CDAH) study, a population-based cohort in Australia. Healthful plant-based diet index (hPDI) scores were derived from food frequency questionnaire data. Plant foods considered 'healthful' were scored positively (e.g., whole grains, fruit, vegetables), with all remaining foods scored reversely (e.g., refined grains, soft drinks, meat). Updated homeostatic model assessment (HOMA2) estimated insulin sensitivity from fasting insulin and glucose concentrations. We used linear mixed-effects regression to analyse data from two time points: CDAH-1 (2004-06, aged 26-36 years) and CDAH-3 (2017-19, aged 36-49 years). hPDI scores were modelled as between- and within-person effects (i.e., a participant's overall mean and their deviation from said mean at each time point, respectively).

RESULTS

The median follow-up duration was 13 years. In our primary analysis, each 10-unit difference in hPDI score was associated with higher log-HOMA2 insulin sensitivity [95% confidence interval], with between-person (β = 0.11 [0.05, 0.17], P < .001) and within-person effects (β = 0.10 [0.04, 0.16], P = .001). The within-person effect persisted despite accounting for compliance with dietary guidelines. Adjustment for waist circumference attenuated the between-person effect by 70% (P = .26) and the within-person effect by 40% (P = .04).

CONCLUSIONS

In young to middle-aged Australian adults, a healthful plant-based eating pattern (determined using hPDI scores) was longitudinally associated with higher insulin sensitivity, and therefore, potentially lower type 2 diabetes risk later in life.

Modeling the progression of Type 2 diabetes with underlying obesity

Environmentally induced or epigenetic-related beta-cell dysfunction and insulin resistance play a critical role in the progression to diabetes. We developed a mathematical modeling framework capable of studying the progression to diabetes incorporating various diabetogenic factors. Considering the heightened risk of beta-cell defects induced by obesity, we focused on the obesity-diabetes model to further investigate the influence of obesity on beta-cell function and glucose regulation. The model characterizes individualized glucose and insulin dynamics over the span of a lifetime. We then fit the model to the longitudinal data of the Pima Indian population, which captures both the fluctuations and long-term trends of glucose levels. As predicted, controlling or eradicating the obesity-related factor can alleviate, postpone, or even reverse diabetes. Furthermore, our results reveal that distinct abnormalities of beta-cell function and levels of insulin resistance among individuals contribute to different risks of diabetes. This study may encourage precise interventions to prevent diabetes and facilitate individualized patient treatment.

Assessing temporal differences of baseline body mass index, waist circumference, and waist-height ratio in predicting future diabetes

Objective

Obesity is the prominent modifiable risk factor known to influence the occurrence and progression of diabetes other than age, and the objective of this study was to evaluate and compare the predictive value of three simple baseline anthropometric indicators of obesity, body mass index (BMI), waist circumference (WC), and waist-height ratio (WHtR), for the occurrence of diabetes at different time points in the future.

Methods

The study subjects were 12,823 individuals with normoglycemic at baseline who underwent health screening and had measurements of BMI, WC, and WHtR. The outcome of interest was new-onset diabetes during follow-up. Time-dependent receiver operator characteristics (ROC) curves of baseline BMI, WC, and WHtR for predicting the risk of diabetes in the next 2 to 12 years were constructed and their area under the ROC curves (AUCs) and corresponding optimal threshold values were calculated for each time point, which were used to compare the accuracy and stability of the above three indicators for predicting the occurrence of diabetes in different future periods.

Results

During a median follow-up period of 7.02 years, with a maximum follow-up of 13 years, 320 new-onset diabetes were recorded. After adjusting for confounders and comparing standardized hazard ratios (HRs), WC was shown to be the best simple anthropometric indicator of obesity reflecting diabetes risk in all models, followed by WHtR. Time-dependent ROC analysis showed that WC had the highest AUC in predicting the occurrence of diabetes in the short term (2-5 years), and WHtR had the highest AUC in predicting the occurrence of diabetes in the medium to long term (6-12 years), while in any time point, both WC and WHtR had higher AUC than BMI in predicting future diabetes. In addition, we found relatively larger fluctuations in the thresholds of BMI and WC for predicting diabetes over time, while the thresholds of WHtR consistently remained between 0.47-0.50; comparatively speaking, WHtR may have greater application value in predicting future diabetes.

Conclusions

Our analysis sustained that central obesity is a more important predictor of diabetes, and in clinical practice, we proposed measuring WHtR as a useful tool for predicting future diabetes.

Pathophysiology, Diagnostic Criteria, and Approaches to Type 2 Diabetes Remission

Diabetes mellitus is a prevalent, life-threatening, and costly medical illness. Type 2 diabetes is defined by insulin resistance caused by persistent hyperglycemia, and it is frequently diagnosed by tests such as fasting blood glucose levels of more than 7.0 mmol/L or HbA1c values of more than 6.5%. Pathogenesis and development of type 2 diabetes mellitus are clearly varied, with genetic and environmental factors both leading to it. The attainment of glycated hemoglobin (HbA1c) levels below the diagnostic level and maintaining it for a minimum of six months without pharmacotherapy, is described as diabetes remission. Diagnosis is a two-part procedure. To begin, the diagnosis of diabetes must be confirmed, and then the type of diabetes must be determined. Even in patients who succeeded to maintain remission, follow-up with the physician and regular tests should be done to prevent any expected diabetes complications.

Metabolically favorable adiposity and bone mineral density: a Mendelian randomization analysis

OBJECTIVE

This analysis assessed the putative causal association between genetically predicted percent body fat and areal bone mineral density (aBMD) and, more specifically, the association between genetically predicted metabolically "favorable adiposity" (MFA) and aBMD at clinically relevant bone sites.

METHODS

Mendelian randomization was used to assess the relationship of MFA and percent body fat with whole-body, lumbar spine, femoral neck, and forearm aBMD. Sex-stratified and age-stratified exploratory analyses were conducted.

RESULTS

In all MR analyses, genetically predicted MFA was inversely associated with aBMD for the whole body (β = -0.053, p = 0.0002), lumbar spine (β = -0.075; p = 0.0001), femoral neck (β = -0.045; p = 0.008), and forearm (β = -0.115; p = 0.001). This negative relationship was strongest in older individuals and did not differ by sex. The relationship between genetically predicted percent body fat and aBMD was nonsignificant across all Mendelian randomization analyses. Several loci that were associated at a genome-wide significance level (p < 5 × 10^-8 ) in opposite directions with body fat and aBMD measures were also identified.

CONCLUSIONS

This study did not support the hypothesis that MFA protects against low aBMD. Instead, it showed that MFA may result in lower aBMD. Further research is needed to understand how MFA affects aBMD and other components of bone health such as bone turnover, bone architecture, and osteoporotic fractures.

Liver, visceral and subcutaneous fat in men and women of South Asian and white European descent: a systematic review and meta-analysis of new and published data

AIMS/HYPOTHESIS

South Asians have a two- to fivefold higher risk of developing type 2 diabetes than those of white European descent. Greater central adiposity and storage of fat in deeper or ectopic depots are potential contributing mechanisms. We collated existing and new data on the amount of subcutaneous (SAT), visceral (VAT) and liver fat in adults of South Asian and white European descent to provide a robust assessment of potential ethnic differences in these factors.

METHODS

We performed a systematic review of the Embase and PubMed databases from inception to August 2021. Unpublished imaging data were also included. The weighted standardised mean difference (SMD) for each adiposity measure was estimated using random-effects models. The quality of the studies was assessed using the ROBINS-E tool for risk of bias and overall certainty of the evidence was assessed using the GRADE approach. The study was pre-registered with the OSF Registries ( https://osf.io/w5bf9 ).

RESULTS

We summarised imaging data on SAT, VAT and liver fat from eight published and three previously unpublished datasets, including a total of 1156 South Asian and 2891 white European men, and 697 South Asian and 2271 white European women. Despite South Asian men having a mean BMI approximately 0.5-0.7 kg/m² lower than white European men (depending on the comparison), nine studies showed 0.34 SMD (95% CI 0.12, 0.55; I²=83%) more SAT and seven studies showed 0.56 SMD (95% CI 0.14, 0.98; I²=93%) more liver fat, but nine studies had similar VAT (-0.03 SMD; 95% CI -0.24, 0.19; I²=85%) compared with their white European counterparts. South Asian women had an approximately 0.9 kg/m² lower BMI but 0.31 SMD (95% CI 0.14, 0.48; I²=53%) more liver fat than their white European counterparts in five studies. Subcutaneous fat levels (0.03 SMD; 95% CI -0.17, 0.23; I²=72%) and VAT levels (0.04 SMD; 95% CI -0.16, 0.24; I²=71%) did not differ significantly between ethnic groups in eight studies of women.

CONCLUSIONS/INTERPRETATION

South Asian men and women appear to store more ectopic fat in the liver compared with their white European counterparts with similar BMI levels. Given the emerging understanding of the importance of liver fat in diabetes pathogenesis, these findings help explain the greater diabetes risks in South Asians.

FUNDING

There was no primary direct funding for undertaking the systematic review and meta-analysis.

Diet, Lifestyle Behaviours and Other Risk Factors Associated With Type 2 Diabetes Beyond Body Mass Index: A Mendelian Randomization Study

OBJECTIVES

Our aim in this study was to identify promising targets for the prevention of type 2 diabetes in addition to weight loss. We conducted a Mendelian randomization (MR) study to investigate the body mass index (BMI)-independent associations of 16 risk factors, including diet, lifestyle behaviours and others, with type 2 diabetes.

METHODS

We selected genetic variants as instrumental variables for diet, sleep traits, smoking, physical activity, education and blood pressure (BP) from European-descent genome-wide association studies (GWASs). Summary statistics for type 2 diabetes were derived from a recent GWAS with 74,124 European cases and 824,006 European controls. The inverse-variance weighted MR method was used to assess the associations of the risk factors with type 2 diabetes, followed by validation of robustness using different MR methods in sensitivity analyses.

RESULTS

Genetically predicted insomnia (odds ratio [OR], 1.10; 95% confidence interval [CI], 1.06 to 1.15), smoking initiation (OR, 1.14; 95% CI, 1.06 to 1.21), educational level (OR, 0.69; 95% CI, 0.65 to 0.74), hypertension (OR, 6.50; 95% CI, 3.13 to 13.50), systolic BP (OR, 1.02; 95% CI, 1.02 to 1.03) and diastolic BP (OR, 1.03; 95% CI, 1.02 to 1.03) had BMI-independent effects on type 2 diabetes risk. In addition, alcohol dependence (OR, 1.10; 95% CI, 1.05 to 1.16; BMI-adjusted OR, 1.04; 95% CI, 0.98 to 1.09) and vegetarian diet (OR, 0.50; 95% CI, 0.33 to 0.74; BMI-adjusted OR, 0.78; 95% CI, 0.57 to 1.06) appeared to be correlated with type 2 diabetes via a BMI-mediated pathway. Sensitivity analyses further confirmed the relationship between these factors and type 2 diabetes.

CONCLUSIONS

In this systematic MR study, insomnia, smoking, education and BP had BMI-independent causal effects on the risk of type 2 diabetes, whereas alcohol dependence and vegetarian diet were associated with type 2 diabetes through BMI.

Microbiome–Gut Dissociation in the Neonate: Autism-Related Developmental Brain Disease and the Origin of the Placebo Effect

While the importance of the intestinal microbiome has been realised for a number of years, the significance of the phrase microbiota–gut–brain axis is only just beginning to be fully appreciated. Our recent work has focused on the microbiome as if it were a single entity, modifying the expression of the genetic inheritance of the individual by the generation of interkingdom signalling molecules, semiochemicals, such as dopamine. In our view, the purpose of the microbiome is to convey information about the microbial environment of the mother so as to calibrate the immune system of the new-born, giving it the ability to distinguish harmful pathogens from the harmless antigens of pollen, for example, or to help distinguish self from non-self. In turn, this requires the partition of nutrition between the adult and its microbiome to ensure that both entities remain viable until the process of reproduction. Accordingly, the failure of a degraded microbiome to interact with the developing gut of the neonate leads to failure of this partition in the adult: to low faecal energy excretion, excessive fat storage, and concomitant problems with the immune system. Similarly, a weakened gut–brain axis distorts interoceptive input to the brain, increasing the risk of psychiatric diseases such as autism. These effects account for David Barker’s 1990 suggestion of “the fetal and infant origins of adult disease”, including schizophrenia, and David Strachan’s 1989 observation of childhood immune system diseases, such as hay fever and asthma. The industrialisation of modern life is increasing the intensity and scale of these physical and psychiatric diseases and it seems likely that subclinical heavy metal poisoning of the microbiome contributes to these problems. Finally, the recent observation of Harald Brüssow, that reported intestinal bacterial composition does not adequately reflect the patterns of disease, would be accounted for if microbial eukaryotes were the key determinant of microbiome effectiveness. In this view, the relative success of “probiotic” bacteria is due to their temporary immune system activation of the gut–brain axis, in turn suggesting a potential mechanism for the placebo effect.

Association between non-alcoholic fatty liver disease and metabolically healthy deterioration across different body shape phenotypes at baseline and change patterns

Non-alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome (MetS), and the relationship between NAFLD and metabolic deterioration remains unclear. This study aimed to investigate dynamic changes in metabolically healthy phenotypes and to assess the impact of non-alcoholic fatty liver disease (NAFLD) on the conversion from metabolically healthy (MH) to metabolically unhealthy (MU) phenotypes across body shape phenotypes and phenotypic change patterns. We defined body shape phenotypes using both the body mass index (BMI) and waist circumference (WC) and defined metabolic health as individuals scoring ≤ 1 on the NCEP-ATP III criteria, excluding WC. A total of 12,910 Chinese participants who were MH at baseline were enrolled in 2013 and followed-up in 2019 or 2020. During a median follow-up of 6.9 years, 27.0% (n = 3,486) of the MH individuals developed an MU phenotype. According to the multivariate Cox analyses, NAFLD was a significant predictor of conversion from the MH to MU phenotype, independent of potential confounders (HR: 1.12; 95% confidence interval: 1.02–1.22). For the MH-normal weight group, the relative risk of NAFLD in phenotypic conversion was 1.21 (95% CI 1.03–1.41, P = 0.017), which was relatively higher than that of MH-overweight/obesity group (HR: 1.14, 95% CI 1.02–1.26, P = 0.013). Interestingly, the effect of NAFLD at baseline on MH deterioration was stronger in the “lean” phenotype group than in the “non-lean” phenotype group at baseline and in the “fluctuating non-lean” phenotype change pattern group than in the “stable non-lean” phenotype change pattern group during follow-up. In conclusion, lean NAFLD is not as benign as currently considered and requires more attention during metabolic status screening.

Microbiome–Gut Dissociation in the Neonate: Obesity and Coeliac Disease as Examples of Microbiome Function Deficiency Disorder

The purpose of this article is to provide a direction for translational research based on an analysis of the nature of complex, immune-related conditions such as obesity and coeliac disease. In essence, it seems that the prevalence of these non-communicable diseases is related to the degradation of the microbiome during the industrialisation of society, and that their nature can be used to infer the functions of the “pre-industrial” microbiome. Based on this analysis, the key point is the necessity for the fully functioning microbiome, acting alongside the parental genetic inheritance of the child, to be in place immediately after birth. In our view, this is achieved by the seemingly accidental process of maternal microbial inheritance during normal birth. Note, however, that this is not possible if the microbiome of the mother is itself degraded following previous problems. Under these conditions the health of a child may be affected from the moment of birth, although, with the exception of atopic diseases, such as eczema and food allergy, the consequences may not become apparent until late childhood or as an adult. In this way, this microbiome function deficiency hypothesis incorporates the epidemiological observations of David Strachan and David Barker in that their onset can be traced to early childhood. Coeliac disease has been chosen as an illustrative example of a multifactorial disorder due to the fact that, in addition to a series of immune system manifestations and a potential problem with food absorption, there is also a significant psychological component. Finally, it is worth noting that an ingestible sensor calibrated to the detection of interkingdom communication molecules (semiochemicals) within the intestine may offer a practical way of assessment and, perhaps, amelioration of at least some of the consequences of non-communicable disease.

Proposal of an obesity classification based on weight history: an official document by the Brazilian Society of Endocrinology and Metabolism (SBEM) and the Brazilian Society for the Study of Obesity and Metabolic Syndrome (ABESO)

Obesity is a chronic disease associated with impaired physical and mental health. A widespread view in the treatment of obesity is that the goal is to normalize the individual's body mass index (BMI). However, a modest weight loss (usually above 5%) is already associated with clinical improvement, while weight losses of 10%-15% bring even further benefits, independent from the final BMI. The percentage of weight reduction is accepted as a treatment goal since a greater decrease in weight is frequently difficult to achieve due to metabolic adaptation along with environmental and lifestyle factors. In this document, the Brazilian Society of Endocrinology and Metabolism (SBEM) and the Brazilian Society for the Study of Obesity and Metabolic Syndrome (ABESO) propose a new obesity classification based on the maximum weight attained in life (MWAL). In this classification, individuals losing a specific proportion of weight are classified as having "reduced" or "controlled" obesity. This simple classification - which is not intended to replace others but to serve as an adjuvant tool - could help disseminate the concept of clinical benefits derived from modest weight loss, allowing individuals with obesity and their health care professionals to focus on strategies for weight maintenance instead of further weight reduction. In future studies, this proposed classification can also be an important tool to evaluate possible differences in therapeutic outcomes between individuals with similar BMIs but different weight trajectories.