Clinical profile of lean NIDDM in South India

Increases in Psychological Stress Are Associated With Higher Fasting Glucose in US Chinese Immigrants

BACKGROUND

The majority of Chinese Americans is foreign-born, and it is well-documented that immigration to the United States (US) leads to increased risk for chronic diseases including type 2 diabetes. Increased disease risk has been attributed to changes in lifestyle behaviors following immigration, but few studies have considered the psychosocial impact of immigration upon biomarkers of disease risk.

PURPOSE

To examine associations of psychological stress and social isolation with markers of type 2 diabetes risk over time among US Chinese immigrants.

METHODS

In this longitudinal study of 614 Chinese immigrants, participants completed assessments of perceived stress, acculturative stress, negative life events, and social isolation annually at three time points. Fasting blood samples were obtained at each time point to measure blood glucose, glycated hemoglobin, and insulin resistance. Mean duration between baseline and follow-up assessments was approximately 2 years.

RESULTS

Increases in migration-related stress, perceived stress and social isolation were associated with significant increases in fasting glucose at follow-up independent of age, body mass index, length of US residence, and other potential covariates. Moreover, increases in glucose varied depending on perceived stress levels at baseline, such that those with higher baseline stress had a steeper increase in glucose over time.

CONCLUSIONS

Psychological stress and social isolation are associated with increases in fasting glucose in a sample of US Chinese immigrants. Findings suggest that the unique experiences of immigration may be involved in the risk of developing type 2 diabetes, a condition that is prevalent among US Chinese despite relatively low rates of obesity.

Managing insulin resistance: the forgotten pathophysiological component of type 2 diabetes

Glucagon-like peptide-1 (GLP-1) receptor agonists have gained widespread use in the treatment of individuals with type 2 diabetes because of their potent weight loss promoting effect, ability to augment β-cell function, and cardiovascular protective effects. However, despite causing impressive weight loss, GLP-1 receptor agonists do not normalise insulin sensitivity in people with type 2 diabetes and obesity, and the long-term effects of this class of antidiabetic medication on muscle mass, frailty, and bone density have been poorly studied. Although GLP-1 receptor agonists improve insulin sensitivity secondary to weight loss, the only true direct insulin-sensitising drugs are thiazolidinediones. Because of side-effects associated with type 2 diabetes therapy, these drugs have not gained widespread use. In lieu of the important role of insulin resistance in the cause of type 2 diabetes and in the pathogenesis of atherosclerotic cardiovascular disease in type 2 diabetes, development of potent insulin-sensitising drugs that can be used in combination with GLP-1 receptor agonists remains a large unmet need in the management of individuals with type 2 diabetes.

Phenotypic characterization of nonautoimmune diabetes in adult Ugandans with low body mass index

Background

Type 2 diabetes is common in relatively lean individuals in sub-Saharan Africa. It is unclear whether phenotypic differences exist between underweight and normal-weight African patients with type 2 diabetes. This study compared specific characteristics between underweight (body mass index <18.5 kg/m2) and normal-weight (body mass index of 18.5-24.9 kg/m2) adult Ugandans with new-onset nonautoimmune diabetes.

Methods

We collected the demographic, clinical, anthropometric, and metabolic characteristics of 160 participants with nonobese new-onset type 2 diabetes (defined as diabetes diagnosed <3 months, body mass index <25 kg/m2, and absence of islet-cell autoimmunity). These participants were categorized as underweight and normal weight, and their phenotypic characteristics were compared.

Results

Of the 160 participants with nonobese new-onset type 2 diabetes, 18 participants (11.3%) were underweight. Compared with those with normal weight, underweight participants presented with less co-existing hypertension (5.6% versus 28.2%, p = 0.04) and lower median visceral fat levels [2 (1-3) versus 6 (4-7), p < 0.001], as assessed by bioimpedance analysis. Pathophysiologically, they presented with a lower median 120-min post-glucose load C-peptide level [0.29 (0.13-0.58) versus 0.82 (0.39-1.50) nmol/l, p = 0.04] and a higher prevalence of insulin deficiency (66.7% versus 31.4%, p = 0.003).

Conclusion

This study demonstrates that nonautoimmune diabetes occurs in underweight individuals in sub-Saharan Africa and is characterized by the absence of visceral adiposity, reduced late-phase insulin secretion, and greater insulin deficiency. These findings necessitate further studies to inform how the prevention, identification, and management of diabetes in such individuals can be individualized.

Diet-induced induction of hepatic Serine/Threonine Kinase STK38 triggers proinflammation and hepatic lipid accumulation

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases worldwide. Although the involvement of chronic overnutrition, systemic inflammation, and insulin resistance in the development of NAFLD is well-established, however, the associations among these remain to be elucidated. Several studies have reported that chronic overnutrition, such as excessive consumption of fats (High Fat Diet, HFD) can cause insulin resistance and inflammation. However, the mechanisms by which HFD exerts inflammation and thereby promotes insulin resistance and intrahepatic fat accumulation remain poorly understood. Here, we show that HFD induces the expression of hepatic Serine/Threonine Kinase 38 (STK38), which further induces systemic inflammation leading to insulin resistance. Notably, Ectopic expression of STK38 in mouse liver leads to lean NAFLD phenotype with hepatic inflammation, insulin resistance, intrahepatic lipid accumulation, and hypertriglyceridemia in mice fed on a regular chow diet. Further, depletion of hepatic STK38 in HFD-fed mice remarkably reduces proinflammation, improves hepatic insulin sensitivity, and decreases hepatic fat accumulation. Mechanistically, two critical stimuli are elicited by STK38 action. For one stimulus, STK38 binds to Tank-Binding protein Kinase1 (TBK1) and induces TBK1 phosphorylation to promote NF-κβ nuclear translocation that mobilizes the release of pro-inflammatory cytokines and eventually leads to insulin resistance. The second, stimulus involves intrahepatic lipid accumulation by enhanced de novo lipogenesis via reducing the AMPK-ACC signaling axis. These findings identify STK38 as a novel nutrient-sensitive pro-inflammatory and lipogenic factor in maintaining hepatic energy homeostasis, and it provides a promising target for hepatic and immune health.

Current Knowledge on the Pathophysiology of Lean/Normal-Weight Type 2 Diabetes

Since early times, being overweight and obesity have been associated with impaired glucose metabolism and type 2 diabetes (T2D). Similarly, a less frequent adult-onset diabetes in low body mass index (BMI) people has been known for many decades. This form is mainly found in developing countries, whereby the largest increase in diabetes incidence is expected in coming years. The number of non-obese patients with T2D is also on the rise among non-white ethnic minorities living in high-income Western countries due to growing migratory flows. A great deal of energy has been spent on understanding the mechanisms that bind obesity to T2D. Conversely, the pathophysiologic features and factors driving the risk of T2D development in non-obese people are still much debated. To reduce the global burden of diabetes, we need to understand why not all obese people develop T2D and not all those with T2D are obese. Moreover, through both an effective prevention and the implementation of an individualized clinical management in all people with diabetes, it is hoped that this will help to reduce this global burden. The purpose of this review is to take stock of current knowledge about the pathophysiology of diabetes not associated to obesity and to highlight which aspects are worthy of future studies.

Underweight Is Associated with a Higher Risk of Acute Pancreatitis in Type 2 Diabetes: A Nationwide Cohort Study

Type 2 diabetes is known as a risk factor for acute pancreatitis, but the risk of acute pancreatitis according to glycemic status and body mass index (BMI) has remained unknown. Therefore, we aim to investigate the risk of acute pancreatitis according to BMI and glycemic status. We included 3,912,496 subjects from the Korean National Health Insurance System cohort who underwent the National Health Screening program in 2009. Each subject’s clinical course was examined through follow-ups until December 2018. BMI and glycemic status were each categorized into five groups. Hazard ratios (HRs) of acute pancreatitis according to BMI and glycemic status were calculated. The adjusted HRs of acute pancreatitis were the highest in the underweight group (BMI < 18.5) in all five glycemic status categories. The HR of acute pancreatitis in the underweight group increased as the glycemic status worsened, excluding the category of diabetes for more than five years (HR 1.381 for normal fasting glucose; 1.805 for impaired fasting glucose; 2.332 for new-onset diabetes; 4.51 for diabetes duration <5 years; 4.135 for diabetes duration ≥5 years). We found that the risk of acute pancreatitis was further increased in the underweight group, depending on the status and duration of type 2 diabetes.

An Atypical Form of Diabetes Among Individuals With Low BMI

OBJECTIVE

Diabetes among individuals with low BMI (<19 kg/m2) has been recognized for >60 years as a prevalent entity in low- and middle-income countries (LMICs) and was formally classified as "malnutrition-related diabetes mellitus" by the World Health Organization (WHO) in 1985. Since the WHO withdrew this category in 1999, our objective was to define the metabolic characteristics of these individuals to establish that this is a distinct form of diabetes.

RESEARCH DESIGN AND METHODS

State-of-the-art metabolic studies were used to characterize Indian individuals with "low BMI diabetes" (LD) in whom all known forms of diabetes were excluded by immunogenetic analysis. They were compared with demographically matched groups: a group with type 1 diabetes (T1D), a group with type 2 diabetes (T2D), and a group without diabetes. Insulin secretion was assessed by C-peptide deconvolution. Hepatic and peripheral insulin sensitivity were analyzed with stepped hyperinsulinemic-euglycemic pancreatic clamp studies. Hepatic and myocellular lipid contents were assessed with 1H-nuclear magnetic resonance spectroscopy.

RESULTS

The total insulin secretory response was lower in the LD group in comparison with the lean group without diabetes and the T2D group. Endogenous glucose production was significantly lower in the LD group than the T2D group (mean ± SEM 0.50 ± 0.1 vs. 0.84 ± 0.1 mg/kg · min, respectively; P < 0.05). Glucose uptake was significantly higher in the LD group in comparison with the T2D group (10.1 ± 0.7 vs. 4.2 ± 0.5 mg/kg · min; P < 0.001). Visceral adipose tissue and hepatocellular lipids were significantly lower in LD than in T2D.

CONCLUSIONS

These studies are the first to demonstrate that LD individuals in LMICs have a unique metabolic profile, suggesting that this is a distinct entity that warrants further investigation.

Maternal low protein diet and fetal programming of lean type 2 diabetes

Maternal nutrition is found to be the key factor that determines fetal health in utero and metabolic health during adulthood. Metabolic diseases have been primarily attributed to impaired maternal nutrition during pregnancy, and impaired nutrition has been an immense issue across the globe. In recent years, type 2 diabetes (T2D) has reached epidemic proportion and is a severe public health problem in many countries. Although plenty of research has already been conducted to tackle T2D which is associated with obesity, little is known regarding the etiology and pathophysiology of lean T2D, a variant of T2D. Recent studies have focused on the effects of epigenetic variation on the contribution of in utero origins of lean T2D, although other mechanisms might also contribute to the pathology. Observational studies in humans and experiments in animals strongly suggest an association between maternal low protein diet and lean T2D phenotype. In addition, clear sex-specific disease prevalence was observed in different studies. Consequently, more research is essential for the understanding of the etiology and pathophysiology of lean T2D, which might help to develop better disease prevention and treatment strategies. This review examines the role of protein insufficiency in the maternal diet as the central driver of the developmental programming of lean T2D.

Local Antibiotic Delivery Systems in Diabetic Foot Osteomyelitis: A Brief Review

Diabetic foot osteomyelitis (DFO) is a severe, difficult to treat infection. Local antibiotic delivery has been studied as a potential therapeutic adjunct following surgery for DFO. This review aims to summarize the evidence on local antibiotic delivery systems in DFO. PubMed database was searched up to March 2020. Overall, 16 studies were identified and included: 3 randomized controlled trials (RCTs), 3 retrospective studies (RSs), and 10 case series. In the RCTs, gentamicin-impregnated collagen sponges significantly improved clinical healing rates and slightly improved duration of hospitalization. In the RSs, antibiotic-impregnated calcium sulfate beads non-significantly improved all healing parameters, but did not reduce post-operative amputation rates or time of healing. The majority of case series used calcium sulfate beads, achieving adequate rates of healing and eradication of infection. In conclusion, evidence for add-on local antibiotic delivery in DFO is still limited; more data are needed to assess this therapeutic measure.

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

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

The Association Between Insulin Resistance, Leptin, and Resistin and Diabetic Nephropathy in Type 2 Diabetes Mellitus Patients with Different Body Mass Indexes

AIM

This study aimed to compare HOMA-IR, leptin, and resistin as the risk factors for diabetic nephropathy in the type 2 diabetes mellitus (T2DM) patients with different BMI classifications.

MATERIALS AND METHODS

A total of 309 patients with T2DM were enrolled in this cross-sectional study. All participants were divided into three groups according to BMI: the normal weight group (18.5 kg/m²≤BMI<24 kg/m²), the overweight group (24kg/m²≤BMI<28 kg/m²) and the obesity group (BMI≥28 kg/m²). The clinical information and laboratory examinations were recorded in detail. Leptin and resistin levels were measured using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Higher HOMA-IR, leptin and resistin levels were found to be the risk factors for diabetic nephropathy when we made comparisons in the total population (P<0.05). In the normal weight group, logistic regression analysis showed that T2DM patients with higher HOMA-IR (OR=4.210, P=0.001), leptin (OR=2.474, P=0.031) and resistin levels (OR=8.299, P<0.001) had nearly 4-fold, 2-fold and 8-fold risk for diabetic nephropathy, respectively, after adjustments. The receiver operating characteristic (ROC) curves indicated that the area under the curves (AUCs) of HOMA-IR and resistin were 0.699 (95% CI 0.617-0.772) and 0.790 (95% CI 0.715-0.854), respectively, which were significantly larger than the AUC of 0.5 (all P<0.001). However, no significant association was observed between HOMA-IR, leptin, and resistin and renal complications (all P>0.05) in the overweight and obesity groups in both logistic regression and AUC analysis.

CONCLUSION

Higher insulin resistance, leptin and resistin levels were observed as risk factors for diabetic nephropathy in T2DM patients with lower BMI. These were not obvious in the overweight and obese patients.

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

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

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

Objectives

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

Methodology

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

Results

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

Conclusion

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

Higher glucagon-to-insulin ratio is associated with elevated glycated hemoglobin levels in type 2 diabetes patients

BACKGROUND/AIMS

The importance of α-cell dysfunction in the pathogenesis of type 2 diabetes has re-emerged recently. However, data on whether relative glucagon excess is present in clinical settings are scarce. We aimed to investigate associations between glucagon-to-insulin ratio and various metabolic parameters.

METHODS

A total of 451 patients with type 2 diabetes naïve to insulin treatment were recruited. Using glucagon-to-insulin ratio, we divided subjects into quartiles according to both fasting and postprandial glucagon-to-insulin ratios.

RESULTS

The mean age of the subjects was 58 years, with a mean body mass index of 25 kg/m2 . The patients in the highest quartile of glucagon-to-insulin ratio had higher glycated hemoglobin (HbA1c) levels. HbA1c levels were positively correlated with both fasting and postprandial glucagon-to-insulin ratios. Subjects in the highest quartile of postprandial glucagon-to-insulin ratio were more likely to exhibit uncontrolled hyperglycemia, even after adjusting for confounding factors (odds ratio, 2.730; 95% confidence interval, 1.236 to 6.028; p for trend < 0.01).

CONCLUSION

Hyperglucagonemia relative to insulin could contribute to uncontrolled hyperglycemia in type 2 diabetes patients.

Diabetes in developing countries

There has been a rapid escalation of type 2 diabetes (T2D) in developing countries, with varied prevalence according to rural vs urban habitat and degree of urbanization. Some ethnic groups (eg, South Asians, other Asians, and Africans), develop diabetes a decade earlier and at a lower body mass index than Whites, have prominent abdominal obesity, and accelerated the conversion from prediabetes to diabetes. The burden of complications, both macro- and microvascular, is substantial, but also varies according to populations. The syndemics of diabetes with HIV or tuberculosis are prevalent in many developing countries and predispose to each other. Screening for diabetes in large populations living in diverse habitats may not be cost-effective, but targeted high-risk screening may have a place. The cost of diagnostic tests and scarcity of health manpower pose substantial hurdles in the diagnosis and monitoring of patients. Efforts for prevention remain rudimentary in most developing countries. The quality of care is largely poor; hence, a substantial number of patients do not achieve treatment goals. This is further amplified by a delay in seeking treatment, "fatalistic attitudes", high cost and non-availability of drugs and insulins. To counter these numerous challenges, a renewed political commitment and mandate for health promotion and disease prevention are urgently needed. Several low-cost innovative approaches have been trialed with encouraging outcomes, including training and deployment of non-medical allied health professionals and the use of mobile phones and telemedicine to deliver simple health messages for the prevention and management of T2D.

Body Mass composition among Underweight Type 2 Diabetes Mellitus Patients-A Cross-sectional Comparative Study

BACKGROUND

Over the past decades, various epidemiological data have shown that the pattern and profile of diabetes mellitus in India are different. The present study was carried out with an aim to study body mass composition in underweight type 2 diabetics and to compare with the normal population.

MATERIALS AND METHODS

The cross-sectional comparative study was conducted between January 2015 and December 2016 and included 60 participants who were selected using the convenient sampling technique. Newly diagnosed patients with type 2 diabetes mellitus and BMI less than 18.5 kg/m2 were considered for the study. Chi square test and Independent student t test were used for finding the statistically significant difference in proportions and between means, respectively; Pearson correlation coefficient was estimated for finding the linear association between two continuous variables.

RESULTS

No statistically significant difference was observed between the two groups in terms of age, waist-hip ratio, and BMI. Higher amount of fat mass and percentage were observed among the patients with diabetes as compared to that of the control group (P value < 0.05). However, there was no statistically significant difference between the underweight and the control group patients (P value > 0.05). A significant positive correlation was observed between HbA1c values and body fat mass values (P value < 0.05).

CONCLUSION

Underweight type 2 diabetic patients were found to have high body fat mass as compared to healthy controls and the HbA1C values of the study participants were found to be positively correlated with fat mass.

High fasting C-peptide levels and insulin resistance in non-lean & non-obese (BMI >19 to < 25 kg/m2) Asian Indians with type 2 diabetes are independently associated with high intra-abdominal fat and liver span

BACKGROUND AND OBJECTIVES

We aimed to compare C-peptide levels & measures of insulin resistance in non-lean & non-obese Asian Indian patients with type 2 diabetes (T2DM) vs. non-lean, non-diabetic controls and to correlate with anthropometric measures, volumes of abdominal adipose tissue depots, pancreas, & liver span.

METHODS

Non-lean, non-obese (BMI >19 and < 25 kg/m²) Asian Indian patients with T2DM, (cases n, 87), diagnosed within one year, on metformin mono therapy, were compared to BMI-matched non-diabetic subjects (controls, n, 37). Measures of glycaemia, insulin and C-peptide levels (fasting and post-prandial), lipid profile, and hepatic transaminases were analysed. Abdominal adipose tissue volumes [subcutaneous & intra-abdominal], pancreatic volume and liver span were assessed using 1.5 Tesla MRI scan.

RESULTS

In cases, the mean values of HbA1c, fasting and post prandial insulin and C-peptide levels, and 3 measures of insulin resistance were significantly higher than controls, but not for HOMA-B. Higher fasting C-peptide levels correlated significantly with HOMA-IR (r = 0.42, p < 0.001), Fasting Insulin Resistance Index (r = 0.42, p < 0.001), Bennett's Index (r = 0.38, p < 0.05), and volumes of SCAT and IAAT only in cases. The independent predictors of higher fasting C-peptide level were IAAT volume (β = 0.057; p = 0.002), liver span (β = 0.057, p = 0.005) and fasting insulin levels (β = 0.35, p = 0.02).

CONCLUSION

Higher fasting and post-prandial C-peptide levels and surrogate measures of insulin resistance in non-obese Asian Indian patients with T2DM are independently associated with IAAT volume and liver span.

Ethnic differences in the prevalence of diabetes in underweight and normal weight individuals: The CARRS and NHANES studies

AIMS

Type 2 diabetes in lean individuals has recently come to attention. We assessed type 2 diabetes prevalence and the associated risk factors in underweight and normal weight individuals in two ethnic populations.

METHODS

We conducted cross-sectional analyses, using representative samples of 4930 Asian Indians from the CARRS-Chennai Study and 2868 Whites from the NHANES Survey. Diabetes was defined as use of glucose lowering medication, fasting glucose ≥126 mg/dl, or 2 h glucose ≥200 mg/dl. Body mass index (BMI) was classified using WHO standard criteria.

RESULTS

Prevalence of type 2 diabetes by BMI varied by ethnicity and sex. In men, type 2 diabetes prevalence was 5.4% and 23.5% in underweight and normal weight Asian Indians and 0.0% and 6.1% in underweight and normal weight Whites. In women, the prevalence was 5.6% and 13.6% in underweight and normal weight Asian Indians and 2.3% and 2.8% in underweight and normal weight Whites. Adjustment for waist circumference, insulin resistance, and insulin secretion did not explain the increased prevalence in Asian Indians.

CONCLUSIONS

These findings suggest significant ethnic differences in type 2 diabetes prevalence without overweight or obesity. Future studies should examine the pathophysiology of type 2 diabetes development in lean individuals.

Body mass index and mortality in people with and without diabetes: A UK Biobank study

BACKGROUND AND AIMS

To investigate the association of body mass index with all-cause, cardiovascular and cancer mortality in individuals with and without diabetes.

METHODS AND RESULTS

We used data on 490,852 participants from the UK Biobank, with linkage to national mortality data between 2006 and 2016. Using Cox regression, we calculated hazard ratios (HRs) and 95% confidence intervals (95%CI) for all-cause, cardiovascular and cancer mortality within body mass index categories in people with and without diabetes adjusting for potential confounders. 24,789 (5.0%) participants reported having diabetes at baseline. Over a median follow-up of 6.9 years, 13,896 participants died, of which 1800 had diabetes. Compared with normal body mass index (18.5-24.9 kg/m²), mortality risk in the overweight group (25.0-29.9 kg/m²) was 33% lower in people with diabetes (HR 0.67, 95%CI 0.62-0.73) and 12% lower in participants without (HR 0.88, 95%CI 0.85-0.90). For class I obesity (30.0-34.9 kg/m²), mortality risk was 35% lower in participants with diabetes (HR 0.65, 95%CI 0.59-0.71) and 5% lower in participants without (HR 0.95, 95%CI 0.91-0.99). For class III obesity (≥40 kg/m²), there was a 10% non-significant lower mortality risk compared to normal body mass index in people with diabetes (HR 0.90, 95%CI 0.77-1.05); in contrast, the risk was 29% higher in people without diabetes (HR 1.29, 95%CI 1.13-1.45). Similar patterns were observed for cardiovascular mortality but not for cancer mortality.

CONCLUSION

The impact of obesity on the risk of mortality was dependent on the presence of diabetes: for the same level of obesity, mortality risk was higher in people without diabetes compared to those with diabetes.

Etiopathological differentiation of diabetes mellitus in lean, young adults

OBJECTIVE

Classification of diabetes mellitus (DM) into type 1 or type 2 is difficult in lean, young individuals. We studied the β-cell function, insulin resistance (IR) and autoimmunity in young patients with recent onset DM.

METHODS

In this cross-sectional study, we included patients (age below 35 years) with recent onset DM (<6 months) and normal body weight for evaluation. The detailed clinical examination was done to identify markers of IR. Autoimmune DM was diagnosed using glutamic acid decarboxylase 65 (GAD₆₅), insulin autoantibody (IAA) and islet cell antibody (ICA). Homeostasis model assessment (HOMA) models of HOMA-B and HOMA- IR were used for estimation of β-cell function and IR respectively. The patients were divided into four groups based on, the autoimmunity (A) and ketosis (K) as group 1 (A+K), group 2 (A-K+), group 3 (A+K-) and group 4 (A-K-). Appropriate statistical tests +)were used to analyze the results.

RESULTS

The study population (n=75, all males) had a mean age of 28.9±4.3years, body mass index 20.6±1.9kg/m², fasting plasma glucose 177.1±31.4mg/dl and HbA1c of 9.9±2.1% at presentation. The number of patients in groups 1 to 4 are 8, 5, 10 and 52 respectively (p<0.0001). HOMA-IR was higher in groups 2 and 4 (4.1±1.3, 3.6±1.1 respectively), whereas HOMA-B was higher in group 4 (3.6±1.5) alone (p=0.0005).

CONCLUSION

Type 2 DM is the most common etiology even in young, lean adults in India. Further studies with large numbers are required to confirm our findings.

Rising trend of diabetes mellitus amongst the undernourished: State -of- the -art review

Diabetes mellitus is prevailing in the malnourished populations congruently in well-nourished ones with an escalating trend in the former group regardless of the absence of obesity as an etiologic determining factor as per the studies in underprivileged sectors of the population. Chronic undernutrition across a lifetime may be an imperative stimulator of diabetes in an individual either by progressively reducing beta cell function alongside islet cell volume and increasing the individual predisposition to other genetic or environmental diabetogenic influences with modifying influence on the course of clinical syndrome. Ketosis resistant insulinopenia is irreversible to the sustained vigorous nutritional convalescence in a substantial fraction of malnourished subjects. It also debunks a latent diabetic stage with insulin resistance reflected by greater insulin requirement in comparison to the patients with type I diabetes with the same beta cell failure fraction and obese type II diabetic patients with equivalent glycemic control gauged by HbA1c levels. Current tendency warrants the replacement of conventional therapy by community oriented theranostic approaches and health programs to curb the epidemic.

Four-year incidence and progression of visual impairment in a South Indian population with diabetes

PURPOSE

The aim of this study is to investigate the 4-year incidence and progression of visual impairment (VI) and the associated risk factors for incident VI in a South Indian population with type 2 diabetes.

METHODS

A total of 634 participants with type 2 diabetes were found eligible after 4 years. Visual acuity (VA) was estimated using the modified Early Treatment Diabetic Retinopathy Study protocol. VA in the better eye was considered for the assessment of VI based on the World Health Organization criteria. Mild VI was defined as VA <20/40 but up to 20/60, moderate VI as VA <20/60 but up to 20/200, severe VI as VA <20/200 but up to 10/200, and blindness as VA worse than 10/200.

RESULTS

The 4-year incidence of any VI, mild VI, moderate VI, severe VI, and blindness was 21.7%, 18.3%, 3.4%, 0.0%, and 0.0%, respectively; of the 13 participants with VI at baseline, 12 (92%) showed worsening/progression of VI on follow-up. Multiple logistic regression showed that nuclear cataract of grades >4.0 (odds ratio [OR]: 2.612 [1.148-5.942], P = 0.022) and lower socioeconomic score (OR: 0.965 [95% confidence interval, (0.933-0.998)], P = 0.040) were associated with the risk of future incident VI. Refractive error (47%) and cataract (30%) were identified as the leading causes of incident VI at follow-up.

CONCLUSIONS

VI seems to be a significant problem among diabetic participants in the South Indian population. Refractive error and cataract are the leading but treatable causes of incident VI in this population and would benefit from intervention.

Assessment of Insulin Sensitivity and its Convalescence with Dietary Rehabilitation in Undernourished Rural West Bengal Population

INTRODUCTION

Metabolic syndrome involving diabetes is acquiring the eminence of prospective epidemic in India with dramatic rise in rural population prevalence where majority are undernourished and creates significant healthcare burden.

AIM

To investigate the prevalence of the insulin resistance amongst the undernourished rural population, involving children, adolescents and adult volunteers of the West Bengal and the effect of nutritional supplementation in the parameters echoing insulin sensitivity.

MATERIALS AND METHODS

A prospective interventional study was carried out on 120 volunteers in three age groups; Group 1 (5-12 years), Group 2 (13-18 years) and Group 3 (19-40 years), each with 40 subjects who fulfilled the inclusion criteria, under informed consent over six months. Baseline data regarding demography, family history including parental history of diabetes, medical history, physical, activity, anthropometrical status and blood parameters echoing insulin sensitivity were obtained from volunteers. Intervention included daily nutritional supplementation with eggs and banana. After six months of food supplementation, parameters reflecting insulin sensitivity were assessed.

RESULTS

Initial low figures of fasting insulin and blood sugar levels improvised with the nutritional supplementation alongside the absence of wasting in Group 1. HOMA-IR and IRI values of the Group 2 improved from the initial figures (3.19, 2.87) to (2.204, 1.99) and that of Group 3 from (5.0, 4.52) to (4.08, 3.67) respectively over six months (p<.05). Average Fasting Blood Sugar (FBS) enhanced from 85.5±9.6 mg/dl to 78.4±7.3 mg/dl and from 90.1±10.2 mg/dl to 84.8±8.4 mg/dl in Group 2 and 3 respectively by the end of the supplementation study (p<.05).

CONCLUSION

Six months study revealed the existence of insulin resistance and malnourishment in the selected rural population in three groups. Decrement in HOMA-IR, IRI, FBS and serum insulin alongside the improvement in the body mass, in comparison to that of initial values is evocative of restoration of insulin sensitivity with nutrition supplementation.

The Association of Metabolic Syndrome with Diabetic Retinopathy: The Korean National Health and Nutrition Examination Survey 2008-2012

Aims

To explore gender differences and associations between metabolic syndrome (MetS) and its components, and diabetic retinopathy (DR) in Korean adults aged 40 years and older with diabetes.

Methods

We analyzed data from the Korean National Health and Nutrition Examination Surveys (2008–2012). In total, 2,576 type 2 diabetic participants, aged 40 and older, were evaluated. Seven standard retinal fundus photographs were obtained after pupil dilation in both eyes. DR was graded using the modified Airlie House classification system. Vision-threatening diabetic retinopathy (VTDR) included proliferative diabetic retinopathy and clinically significant macular edema. MetS was defined according to the Joint Interim Statement, proposed in 2009, by the International Diabetes Federation and the American Heart Association/National Heart, Lung, and Blood Institute. Multivariate logistic regression analysis was used to assess the relationship between MetS and its individual components with DR and VTDR.

Results

After controlling for confounders, MetS was not associated with DR in men or women. Moreover, the risk for DR or VTDR did not increase with increasing MetS components. However, high waist circumference was significantly inversely associated with VTDR (adjusted odds ratio = 0.36; 95% confidence interval = 0.14–0.93) only in men.

Conclusions

MetS was not associated with DR or VTDR in a Korean diabetic population. However, among MetS components, it seems that abdominal obesity was inversely associated with VTDR in Korean diabetic men.

Novel lean type 2 diabetic rat model using gestational low-protein programming

BACKGROUND

Type 2 diabetes (T2D) in lean individuals is not well studied and up to 26% of diabetes occurs in these individuals. Although the cause is not well understood, it has been primarily attributed to nutritional issues during early development.

OBJECTIVE

Our objective was to develop a lean T2D model using gestational low-protein (LP) programming.

STUDY DESIGN

Pregnant rats were fed control (20% protein) or isocaloric LP (6%) diet from gestational day 4 until delivery. Standard diet was given to dams after delivery and to pups after weaning. Glucose tolerance test was done at 2, 4, and 6 months of age. Magnetic resonance imaging of body fat for females was done at 4 months. Rats were sacrificed at 4 and 8 months of age and their perigonadal, perirenal, inguinal, and brown fat were weighed and expressed relative to their body weight. Euglycemic-hyperinsulinemic clamp was done around 6 months of age.

RESULTS

Male and female offspring exposed to a LP diet during gestation developed glucose intolerance and insulin resistance (IR). Further, glucose intolerance progressed with increasing age and occurred earlier and was more severe in females when compared to males. Euglycemic-hyperinsulinemic clamp showed whole body IR in both sexes, with females demonstrating increased IR compared to males. LP females showed a 4.5-fold increase in IR while males showed a 2.5-fold increase when compared to their respective controls. Data from magnetic resonance imaging on female offspring showed no difference in the subcutaneous, inguinal, and visceral fat content. We were able to validate this observation by sacrificing the rats at 4 and 8 months and measuring total body fat content. This showed no differences in body fat content between control and LP offspring in either males or females. Additionally, diabetic rats had a similar body mass index to that of the controls.

CONCLUSION

LP gestational programming produces a progressively worsening T2D model in rats with a lean phenotype without obesity.

Lean diabetes mellitus: An emerging entity in the era of obesity

Much has been published on the characteristics of type 2 diabetes mellitus and its association with the epidemic of obesity. But relatively little is known about the incidence of lean diabetes, progression of disease and fate of the patients with low-normal body mass index (< 25). Studies in developing countries have shown that the clinical characteristics of these patients include history of childhood malnutrition, poor socioeconomic status, relatively early age of onset and absence of ketosis on withdrawal of insulin. In the United States, recent studies showed that the lean, normal weight diabetes is not rare especially among minority populations. They showed that these patients are mainly males, have higher prevalence of insulin use indicating rapid beta cell failure. They might have increased total, cardiovascular and non cardiovascular mortality when compared to obese diabetic patients. In this review, the epidemiologic and clinical features of lean diabetes are presented. The potential causal mechanisms of this emerging diabetes type that may include genetic, autoimmune, acquired and behavioral factors are discussed. The need for studies to further elucidate the causation as well as specific prevention and treatment of lean diabetes is emphasized.

Stressful life events are associated with insulin resistance among Chinese immigrant women in the United States

BACKGROUND

Chinese immigrants experience increased chronic disease risk following migration to the US. Although the impact of lifestyle changes (e.g., diet) on disease risk has been extensively studied, associations of psychosocial stress and disease risk have attracted less attention. Thus, the objective of the present study was to examine associations between stress and insulin resistance in foreign-born Chinese American women.

METHODS

From October, 2005 to April, 2008, 423 women recruited from southeastern Pennsylvania completed questionnaires reporting stressful life events. Blood samples were analyzed for fasting insulin and fasting glucose levels, which were used to estimate insulin resistance according to the homeostasis model assessment (HOMA_IR).

RESULTS

In logistic regression analyses, a greater number of negative life events was associated with insulin resistance (OR=1.17, 95% CI=1.02-1.34), controlling for age, level of acculturation, marital status, body mass index, and waist circumference. Similarly, greater negative life event impact ratings were also associated with insulin resistance (OR=1.08, 95% CI=1.01-1.16) controlling for relevant covariates.

CONCLUSIONS

This is one of the first studies to examine associations between psychosocial stress and insulin resistance in Chinese immigrant women. These findings contribute to a growing body of literature on stress and diabetes risk in an immigrant population.

Prevalence of lean type 2 diabetes mellitus in recently diagnosed type 2 diabetes mellitus patients

INTRODUCTION

Obesity has always been thought to be a risk factor for diabetes; however, some studies in India have reported that even lean people are prone to diabetes. We conducted this study to see if this holds true for this part of the country.

OBJECTIVES

To determine the prevalence of lean type 2 diabetes mellitus (DM) in recently diagnosed type 2 DM in Manipur.

MATERIALS AND METHODS

All recently diagnosed type 2 DM patients, within a period of 24 weeks, who attended the endocrine clinic of RIMS from Jan to Dec 2012 are included in the study. Exclusion criteria are patients with chronic diseases.

RESULTS

Out of the 181 recently diagnosed diabetics 3.9% had a BMI of <19 kg/m(2) of which five are females (5.4% of female patients) and two are males (2.2% of male patients). Mean age of Lean diabetics is 54.86 ± 15.32, mean fasting glucose is 212 ± 105.5 mg% and mean postprandial glucose is 351.57 ± 167.79 mg%. DM complications were observed in 28.6% of the Lean diabetics.

CONCLUSION

Our study shows a low prevalence rate of Lean DM in recently diagnosed type 2 DM.

Autoimmunity, insulin resistance and Beta cell function in subjects with low body weight type 2 diabetes mellitus

In developing countries like India, the majority of Type 2 diabetics are non-obese, and many are "lean" with a body mass index (BMI) below 18.5. This type is referred to as "Low Body Weight Type 2 DM" (LB Type 2 DM). LB Type 2 DM are confused with Type 1 DM or late autoimmune diabetes in adults (LADA) due to their high blood glucose levels and early insulin-requiring state. We assessed pancreatic islet cell autoimmunity by using both glutamic acid decarboxylase 65 antibody (GADA) and anti-IA(2) antibody estimation in 23 patients with LB Type 2 DM and 10 age-matched normal weight (NW) Type 2 DM. Fasting blood glucose (FBG) and 2 hr postchallenge blood glucose (PGBG2) were significantly higher in LB (p < 0.05), while mean values of fasting insulin (24.47 +/- 73.15 muIU/mL vs. 13.4 +/- 16.54 muIU/mL, p > 0.7) and fasting C-peptide (180.81 +/- 357.08 pM/mL vs. 279.83 +/- 281.38 pM/mL, p > 0.5) in LB and NW respectively were not statistically different. All 23 LB and 10 NW subjects were GADA negative while IA(2) positivity was found in 1/23 and 1/10 cases, respectively. LB Type 2 DM revealed good beta cell function with homeostasis model assessment beta cells (HOMAB) values of 57.41 +/- 153.18 as compared to 44.74 +/- 56.24 (p > -0.2) in NW Type 2 DM. Insulin resistance as assessed by homeostasis model assessment insulin resistant (HOMA IR) was 13.50 +/- 42.83 and 5.68 +/- 6.90 (p > 0.6) in LB and NW Type 2 DM, respectively, suggesting that LB Type 2 DM are a phenotypic variant of Type 2 DM.

Intraocular pressure and its determinants in subjects with type 2 diabetes mellitus in India

Objectives

This study was conducted to show the intraocular pressure (IOP) distribution and the factors affecting IOP in subjects with type 2 diabetes mellitus (DM) in India.

Methods

We measured the anthropometric and biochemical parameters for confirmed type 2 DM patients. A comprehensive ocular examination was performed for 1377 subjects aged > 40 years and residing in Chennai.

Results

A significant difference in IOP (mean ± standard deviation) was found between men and women (14.6±2.9 and 15.0±2.8 mmHg, p = 0.005). A significantly elevated IOP was observed among smokers, subjects with systemic hypertension and women with clinically significant macular edema (CSME). After a univariate analysis, factors associated significantly with higher IOP were elevated systolic blood pressure, elevated resting pulse rate and thicker central corneal thickness (CCT). In women, elevated glycosylated hemoglobin was associated with a higher IOP. After adjusting for all variables, the elevated resting pulse rate and CCT were found to be associated with a higher IOP.

Conclusions

Systemic hypertension, smoking, pulse rate and CCT were associated with elevated intraocular pressure in type 2 DM. Women with type 2 DM, especially those with CSME, were more prone to have an elevated IOP.

Prevalence of Visual Impairment and Associated Risk Factors in Subjects with Type II Diabetes Mellitus: Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetics Study (SN-DREAMS, Report 16)

PURPOSE

To report the prevalence of visual impairment (VI) and the associated risk factors in type II diabetic subjects.

MATERIALS AND METHODS

The study included type II diabetes mellitus subjects who were enrolled from a cross-sectional study. Participants underwent biochemical testing and comprehensive ocular examination including stereo fundus photography. The VI was defined based on the World Health Organization criteria.

RESULTS

The prevalence of VI was 4% in the cohort. The risk factors associated with the presence of VI included a female gender, age greater than 60 years, low socio-economic status, hypertension, microalbuminuria, macroalbuminuria, neuropathy, use of insulin and alcohol. Various ocular risk factors are nuclear sclerosis, subjects who have undergone cataract surgery, myopia and sight-threatening diabetic retinopathy (STDR). After adjusting for the factors using stepwise logistic regression analysis, hypertension, use of alcohol, post-cataract surgery and myopia were not risk factors. Stepwise logistic regression analysis indicated that VI was higher among subjects older than 60 years (odds ratio (OR): 4.95 [2.67-9.15]) and those who belonged to a low socio-economic status (OR: 2.91 [1.24-6.85]). The systemic risk factors for VI included microalbuminuria (OR: 2.91 [1.59-5.33]), macroalbuminuria (OR: 4.65 [1.57-13.77]) and presence of neuropathy (OR: 1.97 [1.09-3.59]) among subjects. Subjects with nuclear sclerosis (OR: 36.82 [11.12-112.36]) and presence of STDR (OR: 4.17 [1.54-11.29]) were at a higher risk of VI. Cataract was the most common cause of VI in the cohort.

CONCLUSION

Visual impairment, among type II diabetic subjects (4%), is a major public health problem that needs to be addressed. Cataract is the most common reversible cause of vision impairment in this population.

Mitochondrial bioenergetics is not impaired in nonobese subjects with type 2 diabetes mellitus

Although mitochondrial dysfunction has been well documented in obese people with type 2 diabetes mellitus, its presence or absence in nonobese subjects with type 2 diabetes mellitus has not been well studied so far. The aim of the present study was to assess the status of mitochondrial oxidative phosphorylation in subcutaneous adipose tissue of nonobese type 2 diabetes mellitus subjects in comparison to control, obese nondiabetic, and obese type 2 diabetes mellitus subjects. Mitochondria were isolated from subcutaneous white adipose tissue obtained from the abdominal region of control, obese nondiabetic, nonobese type 2 diabetes mellitus, and obese type 2 diabetes mellitus subjects. The activities of complex I, I to III, II to III, and IV; transmembrane potential; and inorganic phosphate utilization of mitochondria from different groups were measured. Mitochondrial transmembrane potential, inorganic phosphate utilization, and the activities of respiratory chain complexes were significantly reduced in obese nondiabetic and obese type 2 diabetes mellitus patients compared with those in control subjects. No detectable change in mitochondrial functional parameters was observed in case of nonobese type 2 diabetes mellitus subjects compared with control subjects. Furthermore, a significant difference was noticed in mitochondrial phosphate utilization and activities of respiratory complexes, for example, I, I to III, and II to III, between obese type 2 diabetes mellitus subjects and obese nondiabetic subjects. Obesity modulates mitochondrial dysfunction associated with type 2 diabetes mellitus.

Clinical and biochemical profile of lean type 2 diabetes mellitus

BACKGROUND

Type 2 diabetes mellitus is the most prevalent form of diabetes worldwide. In western countries majority of the cases are obese. The scenario may be different in certain parts of India. Various studies have reported a high prevalence of lean type 2 diabetes mellitus with a body mass index < 19 kg/m(2).

MATERIALS AND METHODS

We evaluated 100 cases of lean type 2 diabetes mellitus (62 males and 38 females).

RESULTS AND CONCLUSION

The mean duration of diabetes was 51.7 months (range 5-180 months). The glycemic control was poor according to standard guidelines. The majority of them showed response to oral hypoglycemic agents. Secondary failure to oral hypoglycemic agents was seen in 27 patients. The prevalence of microvascular complications was much higher than macrovascular complications. Neuropathy was the commonest complication seen in 70%, followed by retinopathy in 25%. Only 12 patients had hypertension, one had coronary artery disease and two had cerebrovascular accident. Lipid profile was not significantly deranged in our patients.

Use of a large diabetes electronic medical record system in India: clinical and research applications

BACKGROUND

The diabetes electronic medical record (DEMR) has emerged as an effective information management tool with the potential to improve diabetes care and research. This study reports on the usefulness of the DEMR system at Dr. Mohan's Diabetes Specialities Centre (DMDSC), Chennai, India, for clinical and research purposes.

METHODS

The DEMR, set up in 1996 at DMDSC, connects data of nine centers/clinics in different geographical areas in Southern India. The present data analysis is based on a total of 226,228 patients registered in the DEMR system at DMDSC between the years 1991 and 2010.

RESULTS

The DEMR included data of 139,906 male and 86,322 female patients, of whom 92.6% had type 2 diabetes mellitus (T2DM), 1.4% had type 1 diabetes mellitus (T1DM), and the rest had other types. Patients with T2DM had higher prevalence rates of neuropathy (33.1% vs 13.0%, p < .001), microalbuminuria (25.5% vs 20.0%, p < .001), coronary artery disease (17.5% vs 9.2%, p < .001) and peripheral vascular disease (3.9% vs 2.8%, p = .017) compared with T1DM patients, while prevalence of diabetic retinopathy was similar (37.9% vs 35.7%, p = .06). Prevalence of microvascular and macrovascular complications of diabetes increased with increasing glycated hemoglobin levels (p for trend < .001) and increasing diabetes duration (p for trend < .001).

CONCLUSIONS

The DEMR helps track diabetes care and is a valuable tool for research.

Unique concurrent appearance of two rare conditions in a young girl: central precocious puberty due to hypothalamic hamartoma and uncommon type of diabetes

Hypothalamic hamartomas (HH) are rare congenital nonneoplastic lesions of the tuber cinereum, which usually present as precocious puberty of central origin in young girls and respond well to treatment with long acting gonadotropin releasing hormone (GnRH) analogs. No association of this condition with diabetes mellitus of any form has been reported so far. On the other hand, diabetes mellitus in children and adolescents, when it is not autoimmune type 1 diabetes, is difficult to classify. We present a girl with early onset of central precocious puberty at the age of 8 months, due to hypothalamic hamartoma. Treatment with depot of a GnRH analog for a period of 9 years and 8 months was successful, and her puberty continued 6 months after the discontinuation of triptorelin. At the age of 9 years 6 months, the girl presented with diabetes. She was negative for islet, GAD and IA2 antibodies and her insulinemia and C-peptide remained within normal limits during the 2 years of follow-up. Her metabolic control is excellent with a combination of metformin and a low-dose of mixed insulin. To our knowledge, this is the first description of the simultaneous appearance of these two endocrinological conditions.

Association of obesity with diabetic retinopathy: Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetics Study (SN-DREAMS Report no. 8)

The aim of the study was to report the prevalence of obesity indices in individuals with diabetes and find out their association with diabetic retinopathy in the urban Indian population. Subjects (n = 1,414) were recruited from Sankara Nethralaya Diabetic Retinopathy Epidemiology And Molecular Genetics Study (SN-DREAMS-I), a cross-sectional study between 2003 and 2006. Anthropometric measurements were carried out, and all patients' fundi were photographed using 45 degrees four-field stereoscopic digital photography. The diagnosis of diabetic retinopathy was based on the modified Klein classification. Generalized obesity and abdominal obesity were defined using WHO Asia Pacific guidelines with the BMI (body mass index) cutoff as > or =23 kg/m(2), WC (waist circumference) cutoffs as > or =90 cm in men and > or =80 cm in women and WHO guidelines using WHR (waist-to-hip ratio) cutoffs as > or =0.90 for men and > or =0.85 for women. Prevalence of obesity defined by BMI and WC was more in women compared to men, and that defined by WHR was more in men compared to women (P < 0.001). The prevalence of isolated generalized obesity, isolated abdominal obesity and combined obesity were 5.4, 10.1 and 58% in men and 4.5, 10.8 and 74.4% in women, respectively. The prevalence of any diabetic retinopathy and sight-threatening diabetic retinopathy was more in the isolated abdominal obesity group (26.35 and 6.08%, respectively) than in other subgroups. On logistic regression analysis, isolated abdominal obesity (OR 2.02, 95% CI: 1.06-3.86) and increased WHR in women (OR 1.48 95% CI: 1.10-2.38) were associated with diabetic retinopathy; BMI > or = 23 (OR 0.66, 95% CI: 0.48-0.90) and combined obesity (OR 0.72, 95% CI: 0.53-0.99) had a protective role for any diabetic retinopathy in the overall group. In the urban south Indian population, isolated abdominal obesity and higher WHR in women were associated with diabetic retinopathy, but not with the severity of diabetic retinopathy.

Insulin clamp-derived measurements of insulin sensitivity and insulin secretion in lean and obese asian type 2 diabetic patients

BACKGROUND

The aim of this study was to investigate insulin sensitivity and secretion in lean and obese Asian (Thai) type 2 diabetic patients.

METHODS

Insulin sensitivity and insulin secretion was assessed with the hyperinsulinemic euglycemic (80 mU/m(2) per min) and hyperglycemic clamp technique in 9 lean and 10 obese patients with type 2 diabetes and 4 lean and 4 obese nondiabetic control subjects.

RESULTS

Obese type 2 diabetics had a lower M-value (sensitivity to exogenous insulin) than lean type 2 diabetics (8.7 +/- 1.3 versus 16.5 +/- 1.6 mg . fat free mass kg(-1) . min(-1), P < 0.001) and obese control subjects (15.9 +/- 4.0 mg . fat free mass kg(-1) . min(-1), P < 0.05). Insulin sensitivity (M-value) was similar in lean type 2 diabetics as compared to lean nondiabetic control subjects. During the hyperglycemic clamp, the first (P < 0.001) and second phase (P < 0.02) of insulin and C-peptide response (P < 0.02) was significantly decreased in lean type 2 diabetics as compared to lean nondiabetic subjects. In obese type 2 diabetics, the first and second phase of insulin response was significantly decreased (P < 0.05) compared to obese nondiabetic subjects.

CONCLUSIONS

Obese type 2 diabetics have significant defects in both insulin sensitivity and insulin secretion whereas lean type 2 diabetics demonstrate primarily a defect in insulin secretion. Lean diabetics have similar insulin sensitivity when compared to healthy age- and sex-matched nondiabetic subjects during the euglycemic clamp study, suggesting the lack of significant insulin resistance in lean type 2 diabetics.

Prevalence of refractive errors and associated risk factors in subjects with type 2 diabetes mellitus SN-DREAMS, report 18

PURPOSE

To report the prevalence of refractive errors and the associated risk factors in subjects with type 2 diabetes mellitus from an urban Indian population.

DESIGN

Population-based, cross-sectional study.

PARTICIPANTS

One thousand eighty participants selected from a pool of 1414 subjects with diabetes.

METHODS

A population-based sample of 1414 persons (age >40 years) with diabetes (identified as per the World Health Organization criteria) underwent a comprehensive eye examination, including objective and subjective refractions.

MAIN OUTCOME MEASURES

One thousand eighty subjects who were phakic in the right eye with best corrected visual acuity of > or =20/40 were included in the analysis for prevalence of refractive errors. Univariate and multivariate analyses were done to find out the independent risk factors associated with the refractive errors.

RESULTS

The mean refraction was +0.20+/-1.72, and the Median, +0.25 diopters. The prevalence of emmetropia (spherical equivalent [SE], -0.50 to +0.50 diopter sphere [DS]) was 39.26%. The prevalence of myopia (SE <-0.50 DS), high myopia (SE <-5.00 DS), hyperopia (SE >+0.50 DS), and astigmatism (SE <-0.50 cyl) was 19.4%, 1.6%, 39.7%, and 47.4%, respectively. The advancing age was an important risk factor for the three refractive errors: for myopia, odds ratio (OR; 95% confidence interval [CI] 4.06 [1.74-9.50]; for hyperopia, OR [95% CI] 5.85 [2.56-13.39]; and for astigmatism, OR [95% CI] 2.51 [1.34-4.71]). Poor glycemic control was associated with myopia (OR [95% CI] 4.15 [1.44-11.92]) and astigmatism (OR [95% CI] 2.01 [1.04-3.88]). Female gender was associated with hyperopia alone) OR [95% CI] 2.00 [1.42-2.82].

CONCLUSIONS

The present population-based study from urban India noted a high prevalence of refractive errors (60%) among diabetic subjects >40 years old; the prevalence of astigmatism (47%) was higher than hyperopia (40%) or myopia (20%).

Insulin resistance without obesity induced by cotton pellet granuloma in mice

Obesity leads to insulin resistance because the larger adipocytes in obese persons secrete proinflammatory cytokines that cause chronic inflammation in adipose tissue. This, in turn, leads to the alteration of adipokine secretion, which can induce insulin resistance. However, the development of insulin resistance without obesity is still obscure. We aimed to use an animal inflammation model with cotton pellet granuloma (CPG) in adipose tissue to characterize insulin resistance formation. We found that CPG in epididymal white adipose tissue (WAT), rather than in interscapular brown adipose tissue, impaired insulin sensitivity, and glucose utilization, and that it decreased levels of phosphoinsulin receptor and phospho-Akt in both muscle and liver tissue, but that it did not modify the body weight or food intake in mice. Macrophage infiltration in adipose tissue, leukocyte counts, monocyte chemoattractant protein-1, and interleukin-6 were elevated in CPG-treated mice. However, we found a marked decrease of plasma adiponectin only in the WAT group, which might have been because of the lower level of peroxisome proliferator-activated receptor-gamma in WAT. These results show that granuloma formation in WAT by implantation of a cotton pellet may induce insulin resistance under nonobese condition through circulating inflammatory mediators, especially the low level of adiponectin.

Prevalence and risk factors for diabetic neuropathy in an urban south Indian population: the Chennai Urban Rural Epidemiology Study (CURES-55)

AIMS

This study was conducted to determine the prevalence of, and risk factors for, diabetic neuropathy (DN) in south Indian Type 2 diabetic subjects.

METHODS

Subjects were recruited from the Chennai Urban Rural Epidemiology Study, conducted on a representative cohort from Chennai city. A total of 1629 diabetic subjects were included, of whom 1291 were known to have diabetes (KD) subjects and 338 were randomly selected newly detected diabetic (NDD) subjects. Neuropathy was diagnosed if vibratory perception threshold at the great toe, measured by biothesiometry, exceeded mean + 2 sd of a healthy non-diabetic study population aged 20-45 years (cut point > or = 20 V).

RESULTS

The overall prevalence of DN was 26.1% (age-adjusted 13.1%) with no significant difference in gender. The prevalence of neuropathy was significantly higher in KD subjects compared with NDD subjects (27.8 vs. 19.5%, P = 0.002). The prevalence of diabetic retinopathy (24.1 vs. 15.3%, P < 0.0001) and hypertension (51.1 vs. 40.0%, P < 0.0001) were higher in those with neuropathy compared with those without. The odds ratio for neuropathy in subjects with duration of diabetes > 15 years compared with < or = 5 years was 5.7 (95% confidence interval: 3.52-9.08, P < 0.0001). Regression analysis showed age (P < 0.0001), glycated haemoglobin (P = 0.001) and duration of diabetes (P = 0.045) to be significantly associated with neuropathy.

CONCLUSIONS

This cross-sectional population-based study shows that, among urban south Indian Type 2 diabetic subjects, the prevalence of DN is 26.1% and that DN is significantly associated with age, glycated haemoglobin and duration of diabetes.

Non-obese patients with type 2 diabetes and prediabetic subjects: distinct phenotypes requiring special diabetes treatment and (or) prevention?

A major reason for the increased incidence of type 2 diabetes mellitus (T2DM) across the world is the so-called obesity epidemic, which occurs both in developed and developing countries. However, a large proportion of patients with T2DM in European and, in particular, Asian countries are non-obese. The non-obese T2DM phenotype is characterized by disproportionally reduced insulin secretion and less insulin resistance, as compared with obese patients with T2DM. Importantly, non-obese patients with T2DM have a similar increased risk of cardiovascular disease as obese T2DM patients. The risk of T2DM in non-obese patients is influenced by genetics as well as factors operating in utero indicated by low birth weight. Furthermore, this phenotype is slightly more prevalent among patients with latent autoimmune diabetes in adults, characterized by positive anti-GAD antibodies. The recently identified TCF7L2 gene polymorphism resulting in low insulin secretion influences the risk of T2DM in both obese and non-obese subjects, but is relatively more prevalent among non-obese patients with T2DM. Furthermore, the Pro12Ala polymorphism of the PPAR gamma gene influencing insulin action increases the risk of T2DM in non-obese subjects. Despite a "normal" body mass index, non-obese patients with T2DM are generally characterized by a higher degree of both abdominal and total fat masses (adiposity). Prevention of T2DM with lifestyle intervention is at least as effective in non-obese as in obese prediabetic subjects, and recent data suggest that metformin treatment targeting insulin resistance and non-glycemic cardiovascular disease risk factors is as beneficial in non-obese as in obese patients with T2DM. Nevertheless, non-obese patients with T2DM may progress to insulin treatment more rapidly as compared with obese patients with T2DM.

Prevalence of GAD65 antibodies in lean subjects with type 2 diabetes

While type 2 diabetic subjects in developed countries are predominantly obese or overweight, those in India are often nonobese or lean. The reasons for leanness in these subjects has not been well understood. We assessed the prevalence of pancreatic islet autoimmunity in 83 lean adult subjects (BMI < 18.5 kg/m(2)) with type 2 diabetes by measuring antibodies to glutamic acid decarboxylase-65 (GAD Abs). Positivity to GAD Ab was present in 21 (25.3%) subjects. In addition, subjects with GAD Ab positivity were younger and had lower beta cell function (homeostasis model assessment, HOMA) as compared to the GAD Ab-negative group. This suggests that the antibody-positive group could have a slowly progressive form of type 1 diabetes.

Long-term renal changes in the Goto-Kakizaki rat, a model of lean type 2 diabetes

BACKGROUND

Type 2 diabetes has become the single most frequent cause of end-stage renal disease. The Goto-Kakizaki rat is currently used as a model for lean type 2 diabetes, but its renal changes have not been fully characterized. We investigated long-term functional and structural renal changes in the Goto-Kakizaki rat to evaluate if this animal model resembles the changes observed in human diabetic kidney disease.

METHODS

Urinary albumin excretion, creatinine clearance and blood pressure were measured at the age of 2, 8 and 14 months in 12 female Goto-Kakizaki rats and 10 female, non-diabetic Wistar rats. To study kidney morphology, kidney weight, glomerular volume, basement membrane thickness, mesangial fraction and total mesangial volume were determined at 14 months.

RESULTS

Urinary albumin excretion rose progressively over time in both groups, but was significantly higher in Goto-Kakizaki rats than in Wistar rats. Creatinine clearance decreased over time in Goto-Kakizaki rats but not in Wistar rats. Blood pressure was in the normotensive range in all animals throughout the study. Kidney weight, glomerular volume, basement membrane thickness, mesangial fraction and total mesangial volume were significantly higher in Goto-Kakizaki rats than in Wistar rats. Body weight and blood glucose levels were higher, whereas serum insulin levels were not different or lower in Goto-Kakizaki rats compared with Wistar rats.

CONCLUSION

The Goto-Kakizaki rat is a lean, hyperglycaemic, euinsulinaemic, normotensive experimental model of type 2 diabetes with robust functional and structural renal changes.