Heterogeneity of non-insulin-dependent diabetes expressed as variability in insulin sensitivity, beta-cell function and cardiovascular risk profile

Genetic association of lipid-lowering drug target genes with erectile dysfunction and male reproductive health

Objective

The effect of hypolipidemic drugs on male erectile function is still controversial. This Mendelian randomization (MR) study aimed to explore the potential impact of lipid-lowering drug targets on ED.

Methods

We collected seven genetic variants encoding lipid-lowering drug targets (LDLR, HMGCR, NPC1L1, PCSK9, APOB, APOC3 and LPL) from published genome-wide association study (GWAS) statistics, and performed drug target MR analysis. The risk of ED was defined as the primary outcome, sex hormone levels and other diseases as the secondary outcomes. Mediation analyses were performed to explore potential mediating factors.

Results

The results showed that LDLR, LPL agonists and APOC3 inhibitors were significantly associated with a reduced risk of ED occurrence. APOB inhibitors were associated with an increased risk of ED occurrence. In terms of sex hormone levels, LDLR and LPL agonists were significantly associated with increased TT levels, and HMGCR was associated with decreased TT and BT levels significantly. In terms of male-related disease, MR results showed that LDLR agonists and PCSK9 inhibitors were significantly associated with an elevated risk of PH; HMGCR, NPC1L1 inhibitors were associated with a reduced risk of PCa; and LDLR agonists were significantly associated with a reduced risk of AS and MI; in addition, HMGCR inhibitors were associated with a reduced risk of PCa.

Conclusion

After performing drug-targeted MR analysis, we found that that there was a causal relationship between lipid-lowering drug targets and ED. APOC3, APOB, LDLR and LPL may be new candidate drug targets for the treatment of ED.

Toward an Improved Classification of Type 2 Diabetes: Lessons From Research into the Heterogeneity of a Complex Disease

CONTEXT

Accumulating evidence indicates that type 2 diabetes (T2D) is phenotypically heterogeneous. Defining and classifying variant forms of T2D are priorities to better understand its pathophysiology and usher clinical practice into an era of "precision diabetes."

EVIDENCE ACQUISITION AND METHODS

We reviewed literature related to heterogeneity of T2D over the past 5 decades and identified a range of phenotypic variants of T2D. Their descriptions expose inadequacies in current classification systems. We attempt to link phenotypically diverse forms to pathophysiology, explore investigative methods that have characterized "atypical" forms of T2D on an etiological basis, and review conceptual frameworks for an improved taxonomy. Finally, we propose future directions to achieve the goal of an etiological classification of T2D.

EVIDENCE SYNTHESIS

Differences among ethnic and racial groups were early observations of phenotypic heterogeneity. Investigations that uncover complex interactions of pathophysiologic pathways leading to T2D are supported by epidemiological and clinical differences between the sexes and between adult and youth-onset T2D. Approaches to an etiological classification are illustrated by investigations of atypical forms of T2D, such as monogenic diabetes and syndromes of ketosis-prone diabetes. Conceptual frameworks that accommodate heterogeneity in T2D include an overlap between known diabetes types, a "palette" model integrated with a "threshold hypothesis," and a spectrum model of atypical diabetes.

CONCLUSION

The heterogeneity of T2D demands an improved, etiological classification scheme. Excellent phenotypic descriptions of emerging syndromes in different populations, continued clinical and molecular investigations of atypical forms of diabetes, and useful conceptual models can be utilized to achieve this important goal.

Defining and Classifying New Subgroups of Diabetes

An etiologically based classification of diabetes is needed to account for the heterogeneity of type 1 and type 2 diabetes (T1D and T2D) and emerging forms of diabetes worldwide. It may be productive for both classification and clinical discovery to consider variant forms of diabetes as a spectrum. Maturity onset diabetes of youth and neonatal diabetes serve as models for etiologically defined, rare forms of diabetes in the spectrum. Ketosis-prone diabetes is a model for more complex forms, amenable to phenotypic dissection. Bioinformatic approaches such as clustering analyses of large datasets and multi-omics investigations of rare and atypical phenotypes are promising avenues to explore and define new subgroups of diabetes.

Identification of novel population clusters with different susceptibilities to type 2 diabetes and their impact on the prediction of diabetes

Type 2 diabetes is one of the subtypes of diabetes. However, previous studies have revealed its heterogeneous features. Here, we hypothesized that there would be heterogeneity in its development, resulting in higher susceptibility in some populations. We performed risk-factor based clustering (RFC), which is a hierarchical clustering of the population with profiles of five known risk factors for type 2 diabetes (age, gender, body mass index, hypertension, and family history of diabetes). The RFC identified six population clusters with significantly different prevalence rates of type 2 diabetes in the discovery data (N = 10,023), ranging from 0.09 to 0.44 (Chi-square test, P < 0.001). The machine learning method identified six clusters in the validation data (N = 215,083), which also showed the heterogeneity of prevalence between the clusters (P < 0.001). In addition to the prevalence of type 2 diabetes, the clusters showed different clinical features including biochemical profiles and prediction performance with the risk factors. SOur results seem to implicate a heterogeneous mechanism in the development of type 2 diabetes. These results will provide new insights for the development of more precise management strategy for type 2 diabetes.

Common autoimmune biomarkers, thyroid hormonal abnormalities, and beta cells dysfunction in patients with latent autoimmune diabetes in adults with type II diabetes mellitus

AIM

Latent autoimmune diabetes in adults (LADA) is autoimmune diabetes with a slow progression characterized by the presence of antibodies associated with Type I diabetes. The present study aimed to assess autoimmune characteristics in patients with LADA in Iran. We attempted to obtain a clear view of autoimmune conditions in LADA among our population.

METHODS

This study was sourced from the population-based survey of KERCARDS aiming assessment of cardiovascular risk factors among a great sample of Iranian population who were resident in Kerman, a great province in southern Iran. Among all diabetic patients who were negative for Anti Glutamic Acid Decarboxylase (GAD) antibody test, 120 were selected as the controls and among 80 patients who were positive for this test diagnosed as LADA, the recorded files of 57 patients were complete considered as the cases.

RESULTS

The level of thyroxin is significantly lower in patients with LADA compared with the controls so 73.7% and 45% of patients had normal level of thyroxin, respectively. Also, those with LADA had considerably lower levels of both thyroid peroxydaseantibody (TPO-Ab) and C-peptide when compared with non-LADA group. Using multivariate analyses and with the presence of baseline variables including gender, age, and duration of disease, the diagnosis of LADA was associated with lower serum levels of Anti-TPO, C-peptide, and thyroxin, but not associated with the level of Anti-TTG in serum.

CONCLUSION

LADA patients may face with lower serum levels of C-peptide and thyroid-specific antibodies indicating insulin therapy requirement and authoimmune fundaments of the disease, respectively.

WITHDRAWN: Sulphonylurea monotherapy for patients with type 2 diabetes mellitus

The Cochrane Metabolic and Endocrine Disorders Group withdrew this review as of Issue 7, 2015 because of the involvement of one author (SS Lund) being employed in a pharmaceutical company. The authors of the review and the Cochrane Metabolic and Endocrine Disorders Group did not find that this was a breach of the rules of the Cochrane Collaboration at the time when it was published. However, after the publication of the review, the Cochrane Collaboration requested withdrawal of the review due to the employment of the author. A new protocol for a review to cover this topic will be published. This will have a new title and a markedly improved protocol fulfilling new and important developments and standards within the Cochrane Collaboration as well as an improved inclusion and search strategy making it necessary to embark on a completely new review project.

The editorial group responsible for this previously published document have withdrawn it from publication.

Biochemical and nutritional markers and antioxidant activity in metabolic syndrome

BACKGROUND AND OBJECTIVES

1) Nutritional assessment of the diet followed by patients with metabolic syndrome, and 2) biochemical analysis of the oxidation-reduction level in patients with metabolic syndrome.

MATERIAL AND METHODS

A cross-sectional study was conducted in patients with metabolic syndrome in Murcia. Fifty-three patients, 33 with and 20 without (control group) metabolic syndrome, were selected. The intervention consisted of completion of a recall survey and a test to nutritionally assess dietary intake. Anthropometric and laboratory variables, including those related to antioxidant activity, were also tested.

RESULTS

Antioxidant activity was within normal limits in both groups (1.7 ± 0.2 mmol/L in the control group and 1.8 ± 0.1 mmol/L in the metabolic syndrome group) (NS). Superoxide dismutase levels were not significantly different between the groups. Mean glutathione reductase levels (U/L) were higher in the control group as compared to patients with metabolic syndrome (P<.05). As regards oxidative stress biomarkers, mean isoprostane levels were higher in the control group (4.9 ± 6.2 ng/mL) than in metabolic syndrome patients (3.5 ± 3.9 ng/mL) (P<.05). Oxidized LDL values tended to be higher in metabolic syndrome patients (96 ± 23.2U/L) as compared to the control group (86.2 ± 17.3 U/L), but differences were not significant.

CONCLUSIONS

There is a trend to a poorer nutritional and biochemical profile in patients with metabolic syndrome, who also tend to have a greater degree of oxidative stress.

Risk factors for type 2 diabetes mellitus preceded by β-cell dysfunction, insulin resistance, or both in older adults: the Cardiovascular Health Study

Insulin resistance (IR) and pancreatic β-cell dysfunction lead to type 2 diabetes mellitus (DM). We tested whether risk factors would differ for DM that was preceded predominantly by IR, β-cell dysfunction, or both among 4,384 older adults (mean age, 72.7 (standard deviation, 5.6) years) in the Cardiovascular Health Study, which was conducted in North Carolina, California, Maryland, and Pennsylvania (1989-2007). When evaluating established risk factors, we found older age, greater adiposity, higher systolic blood pressure, a lower high-density lipoprotein cholesterol level, a higher triglyceride level, and a lower alcohol intake to be independently associated with greater IR but, conversely, with better β-cell function (P < 0.001). The prospective associations between some risk factors and incident DM varied significantly depending on whether DM was preceded predominantly by IR, β-cell dysfunction, or both. For example, obesity and lower high-density lipoprotein cholesterol levels were positively associated with DM preceded predominantly by IR (hazard ratio (HR) = 5.02, 95% confidence interval (CI): 2.81, 9.00; and HR = 1.97, 95% CI: 1.32, 2.93, respectively), with a significant association with and an insignificant trend toward a lower risk of DM preceded predominantly by β-cell dysfunction (HR = 0.33, 95% CI: 0.14, 0.80; and HR = 0.78, 95% CI: 0.43, 1.39, respectively). In conclusion, among older adults, DM risk factors were differentially associated with DM preceded predominantly by IR or β-cell dysfunction. Biologic and clinical implications of putative subtypes of DM require further investigation.

Sulphonylurea monotherapy for patients with type 2 diabetes mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a growing health problem worldwide. Whether sulphonylureas show better, equal or worse therapeutic effects in comparison with other antidiabetic interventions for patients with T2DM remains controversial.

OBJECTIVES

To assess the effects of sulphonylurea monotherapy versus placebo, no intervention or other antidiabetic interventions for patients with T2DM.

SEARCH METHODS

We searched publications in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, LILACS and CINAHL (all until August 2011) to obtain trials fulfilling the inclusion criteria for our review.

SELECTION CRITERIA

We included clinical trials that randomised patients 18 years old or more with T2DM to sulphonylurea monotherapy with a duration of 24 weeks or more.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the risk of bias. The primary outcomes were all-cause and cardiovascular mortality. Secondary outcomes were other patient-important outcomes and metabolic variables. Where possible, we used risk ratios (RR) with 95% confidence intervals (95% CI) to analyse the treatment effect of dichotomous outcomes. We used mean differences with 95% CI to analyse the treatment effect of continuous outcomes. We evaluated the risk of bias. We conducted trial sequential analyses to assess whether firm evidence could be established for a 10% relative risk reduction (RRR) between intervention groups.

MAIN RESULTS

We included 72 randomised controlled trials (RCTs) with 22,589 participants; 9707 participants randomised to sulphonylureas versus 12,805 participants randomised to control interventions. The duration of the interventions varied from 24 weeks to 10.7 years. We judged none of the included trials as low risk of bias for all bias domains. Patient-important outcomes were seldom reported.First-generation sulphonylureas (FGS) versus placebo or insulin did not show statistical significance for all-cause mortality (versus placebo: RR 1.46, 95% CI 0.87 to 2.45; P = 0.15; 2 trials; 553 participants; high risk of bias (HRB); versus insulin: RR 1.18, 95% CI 0.88 to 1.59; P = 0.26; 2 trials; 1944 participants; HRB). FGS versus placebo showed statistical significance for cardiovascular mortality in favour of placebo (RR 2.63, 95% CI 1.32 to 5.22; P = 0.006; 2 trials; 553 participants; HRB). FGS versus insulin did not show statistical significance for cardiovascular mortality (RR 1.36, 95% CI 0.68 to 2.71; P = 0.39; 2 trials; 1944 participants; HRB). FGS versus alpha-glucosidase inhibitors showed statistical significance in favour of FGS for adverse events (RR 0.63, 95% CI 0.52 to 0.76; P = 0.01; 2 trials; 246 participants; HRB) and for drop-outs due to adverse events (RR 0.28, 95% CI 0.12 to 0.67; P = 0.004; 2 trials; 246 participants; HRB).Second-generation sulphonylureas (SGS) versus metformin (RR 0.98, 95% CI 0.61 to 1.58; P = 0.68; 6 trials; 3528 participants; HRB), thiazolidinediones (RR 0.92, 95% CI 0.60 to 1.41; P = 0.70; 7 trials; 4955 participants; HRB), insulin (RR 0.96, 95% CI 0.79 to 1.18; P = 0.72; 4 trials; 1642 participants; HRB), meglitinides (RR 1.44, 95% CI 0.47 to 4.42; P = 0.52; 7 trials; 2038 participants; HRB), or incretin-based interventions (RR 1.39, 95% CI 0.52 to 3.68; P = 0.51; 2 trials; 1503 participants; HRB) showed no statistically significant effects regarding all-cause mortality in a random-effects model. SGS versus metformin (RR 1.47; 95% CI 0.54 to 4.01; P = 0.45; 6 trials; 3528 participants; HRB), thiazolidinediones (RR 1.30, 95% CI 0.55 to 3.07; P = 0.55; 7 trials; 4955 participants; HRB), insulin (RR 0.96, 95% CI 0.73 to 1.28; P = 0.80; 4 trials; 1642 participants; HRB) or meglitinide (RR 0.97, 95% CI 0.27 to 3.53; P = 0.97; 7 trials, 2038 participants, HRB) showed no statistically significant effects regarding cardiovascular mortality. Mortality data for the SGS versus placebo were sparse. SGS versus thiazolidinediones and meglitinides did not show statistically significant differences for a composite of non-fatal macrovascular outcomes. SGS versus metformin showed statistical significance in favour of SGS for a composite of non-fatal macrovascular outcomes (RR 0.67, 95% CI 0.48 to 0.93; P = 0.02; 3018 participants; 3 trials; HRB). The definition of non-fatal macrovascular outcomes varied among the trials. SGS versus metformin, thiazolidinediones and meglitinides showed no statistical significance for non-fatal myocardial infarction. No meta-analyses could be performed for microvascular outcomes. SGS versus placebo, metformin, thiazolidinediones, alpha-glucosidase inhibitors or meglitinides showed no statistical significance for adverse events. SGS versus alpha-glucosidase inhibitors showed statistical significance in favour of SGS for drop-outs due to adverse events (RR 0.48, 95% CI 0.24 to 0.96; P = 0.04; 9 trials; 870 participants; HRB). SGS versus meglitinides showed no statistical significance for the risk of severe hypoglycaemia. SGS versus metformin and thiazolidinediones showed statistical significance in favour of metformin (RR 5.64, 95% CI 1.22 to 26.00; P = 0.03; 4 trials; 3637 participants; HRB) and thiazolidinediones (RR 6.11, 95% CI 1.57 to 23.79; P = 0.009; 6 trials; 5660 participants; HRB) for severe hypoglycaemia.Third-generation sulphonylureas (TGS) could not be included in any meta-analysis of all-cause mortality, cardiovascular mortality or non-fatal macro- or microvascular outcomes. TGS versus thiazolidinediones showed statistical significance regarding adverse events in favour of TGS (RR 0.88, 95% CI 0.78 to 0.99; P = 0.03; 3 trials; 510 participants; HRB). TGS versus thiazolidinediones did not show any statistical significance for drop-outs due to adverse events. TGS versus other comparators could not be performed due to lack of data.For the comparison of SGS versus FGS no meta-analyses of all-cause mortality, cardiovascular mortality, non-fatal macro- or microvascular outcomes, or adverse events could be performed.Health-related quality of life and costs of intervention could not be meta-analysed due to lack of data.In trial sequential analysis, none of the analyses of mortality outcomes, vascular outcomes or severe hypoglycaemia met the criteria for firm evidence of a RRR of 10% between interventions.

AUTHORS' CONCLUSIONS

There is insufficient evidence from RCTs to support the decision as to whether to initiate sulphonylurea monotherapy. Data on patient-important outcomes are lacking. Therefore, large-scale and long-term randomised clinical trials with low risk of bias, focusing on patient-important outcomes are required.

Insulin-stimulated increase in serum leptin levels precedes and correlates with weight gain during insulin therapy in type 2 diabetes

CONTEXT

Infusion of insulin acutely stimulates leptin production and chronic insulin treatment is associated with elevated serum leptin levels and body weight in subjects with type 2 diabetes.

OBJECTIVE

The objective of the study was to investigate the relationship between insulin administration, leptin levels, and weight gain in subjects with type 2 diabetes.

DESIGN

This was a post hoc analysis of two randomized, controlled trials.

SETTING

The study was conducted at an outpatient clinic.

SUBJECTS

Subjects included 35 (study 1) and 32 (study 2) poorly controlled oral hypoglycemic agent (OHA)-treated type 2 diabetic subjects.

INTERVENTION

Study 1: subjects were investigated during a hyperinsulinemic, euglycemic glucose clamp and 12 months after being randomly allocated to start insulin or continue on OHAs. Study 2: 1 yr treatment with either OHAs and lifestyle intervention or insulin with or without concomitant lifestyle intervention.

MAIN OUTCOME MEASURE

Changes in serum leptin levels during clamp and during 1 yr of treatment in relationship to changes in body weight.

RESULTS

Study 1: during acute insulin infusion leptin levels increased by 10% (P < 0.001). During 1 yr of insulin therapy, mean body weight increased by 6%, whereas the fasting leptin levels increased by 108% (both P < 0.001). The weight gain observed at 1 yr correlated with the increase in leptin levels observed during the clamp (r = 0.62, P = 0.003). Study 2: mean body weight increased by 4% (P < 0.01), whereas leptin levels increased by 56% (P < 0.001) during 1 yr of insulin treatment and the increase in leptin preceded the increase in body weight.

CONCLUSIONS

Significant correlations were observed between insulin's effect on serum leptin levels and the increase in weight that accompanied insulin therapy.

HNF1A gene polymorphisms and cardiovascular risk factors in individuals with late-onset autosomal dominant diabetes: a cross-sectional study

Background

Type 2 diabetes mellitus (T2DM) is a genetically heterogeneous disease, hepatocyte nuclear factor-1 homeobox A (HNF1A) single-nucleotide polymorphisms (SNPs) playing a minor role in its pathogenesis. HNF1A is a frequent cause of monogenic diabetes, albeit with early-onset. Some uncommon subgroups like late-onset autosomal dominant diabetes mellitus (LOADDM) may present peculiar inheritance patterns with a stronger familial component. This study aims to investigate the relationship of HNF1A SNPs with cardiovascular risk factors in this group, as well as to characterize them in contrast with classical T2DM (CT2DM).

Methods

eighteen LOADDM (age at onset > 40 y.o.; diabetes in 3 contiguous generations, uniparental lineage) along with 48 CT2DM patients and 42 normoglycemic controls (N group) have been evaluated for cardiovascular risk factors and SNPs of HNF1A.

Results

LOADDM showed significantly higher frequencies of SNPs A98V (22.2% vs 2.1%, p = 0.02) and S487N (72.2% vs 43.8%, p = 0.049) of HNF1A compared to CT2DM. I27L did not show significant difference (66.7% vs 45.8%), but associated with lower risk of hypertriglyceridemia (OR 0.16, 95% CI 0.04–0.65, p = 0.01). "Protective effect" was independent from other well-known predictive risk factors for hypertriglyceridemia, such as waist circumference (OR 1.09 per 1 cm increase, p = 0.01) and HDL (OR 0.01 per 1 mmol/l, p = 0.005), after logistic regression.

Conclusion

Late onset autosomal dominant diabetes mellitus is clinically indistinguishable from classical type 2 diabetes individuals. However, LOADDM group is enriched for common HNF1A polymorphisms A98V and S487N. I27L showed "protective effect" upon hypertriglyceridemia in this sample of individuals, suggesting a role for HNF1A on diabetic individuals' lipid profile. These data contribute to the understanding of the complex interactions between genes, hyperglycemia and cardiovascular risk factors development in type 2 diabetes mellitus.

Insulin, glucose and glycated hemoglobin in Alzheimer’s and vascular dementia with and without superimposed Type II diabetes mellitus condition

Increased concentrations of insulin, glucose and glycohemoglobin are associated with Type II diabetes mellitus (DM) and recognized as characteristic markers of the disease; in Alzheimer's (AD), Vascular dementia (VaD), and both dementia's with superimposed diabetes (AD + DM, VaD + DM) the knowledge is scarce. The sample (n = 122; males = 60; mean age = 73 +/- 7) comprised DM, AD, VaD, AD + DM, and VaD + DM patients, and healthy controls (C). The ANOVA's yielded significant differences between groups: Insulin p = 3.7 x 10(-3); Glucose p < 10(-12); Glycohemoglobin p = 9.2x10(-4). Comparisons between groups (DM vs. C, AD + DM vs. AD, VaD + DM vs. VaD, and demented DM vs. non-demented DM) resulted significant for all variables (Bonferroni's statistic, alpha = 0.05). Diabetic and diabetic demented patients presented significant increases largely different from controls (0.01 < p < 0.001), unlike the non-significant changes in their non-diabetic counterparts; linear relationships were found across all groups. The correlation's insulin/glucose and insulin/glycohemoglobin change to positive within demented groups, indicating a different performance of insulin in demented and non-demented subjects.

T-cell responses to islet antigens improves detection of autoimmune diabetes and identifies patients with more severe beta-cell lesions in phenotypic type 2 diabetes

Latent autoimmune diabetes in adults or type 1.5 diabetes is considered to be a T-cell-mediated autoimmune disease. However, identification of patients is based commonly on autoantibody (Ab) detection. To determine whether measuring T-cell reactivity to islet proteins compared with measuring Abs improves detection of autoimmune diabetes and how beta-cell function correlates with T-cell reactivity compared with Ab positivity, we assessed the T-cell proliferative responses and Ab responses (islet cell autoantibodies, insulin autoantibodies, insulinoma-associated protein-2 autoantibodies, and GAD Abs) to islet proteins of 36 phenotypic type 2 diabetic patients. To be considered Ab(+) or T-cell(+), patients were required to be positive for a minimum of two consecutive time points. beta-Cell function was measured with fasting and glucagon-stimulated C-peptide. Independent of T-cell reactivity, Ab(+) and Ab(-) patients had comparable fasting and glucagon-stimulated C-peptide. Independent of Ab status, T-cell(+) patients demonstrated significantly lower glucagon-stimulated (P < 0.003) C-peptide compared with T-cell(-) patients. These data suggest that measuring T-cell responses to multiple islet proteins in phenotypic type 2 diabetic patients improves identification of patients with autoimmune diabetes and delineates those who have a more severe beta-cell lesion compared with Ab assessment alone.

The effect of 6 months supplementation with conjugated linoleic acid on insulin resistance in overweight and obese

BACKGROUND

Contradicting results have been published regarding the effect of conjugated linoleic acid (CLA) on insulin resistance. However, only a few studies have used the euglycemic hyperinsulinemic clamp method, which is considered the standard for measuring insulin resistance.

OBJECTIVE

To evaluate if CLA as a mixture of the main isomers trans-10 cis-12 and cis-9 trans-11 affects the insulin resistance in healthy overweight and obese male and female adults.

DESIGN

The main study was a randomized, double-blind, placebo-controlled trial with change in body composition as primary end point comprising 118 subjects receiving supplementation with either placebo (olive oil) or CLA (Clarinol) for 6 months. A sub-population of 49 subjects agreed additionally to participate in an euglycemic hyperinsulinemic clamp study at baseline and after 6 months of supplementation with study drug. The primary outcome was the change in glucose uptake (M) as measured by the hyperinsulinemic euglycemic glucose clamp method. Secondary outcomes were the correlates between insulin resistance and changes in body composition or blood chemistry parameters. Forty-one subjects completed the clamp test at both time points.

RESULTS

The median M of the CLA group was 11.0 mg min(-1) lean body mass (lbm)(-1) (n=24) at baseline, 10.3 mg min(-1) lbm(-1) (n=24) after 6 months, and the median difference was +0.21 mg min(-1) lbm(-1) (n=24). The median M of placebo group was 8.4 mg min(-1) lbm(-1) at baseline and 9.3 mg min(-1) lbm(-1) after 6 months and the median difference was -0.22 mg min(-1) lbm(-1) (n=17). No significant (P<0.05) differences were found within groups or between groups. Likewise, the glucose uptake insulin concentration ratio during clamp (M/I) was independent of treatment and time. Homeostasis model assessment (HOMA) and quantitative insulin sensitivity check index derived from fasting glucose and insulin were also independent of treatment and time, and HOMA for the clamp population (n=49) corresponded well with HOMA for the per protocol population (n=83). Correlation analysis showed that changes in M were inversely correlated to changes in glucohemoglobin (P=0.002), but did not correlate with changes in either glucose, insulin, insulin c-peptide, leptin, adiponectin or percent body fat.

CONCLUSIONS

CLA does not affect glucose metabolism or insulin sensitivity in a population of overweight or obese volunteers.

The clinical characteristics of latent autoimmune diabetes in adults and its relation with chronic complications in metabolically poor controlled Turkish patients with Type 2 diabetes mellitus

It has been reported that some patients with Type 2 diabetes mellitus (DM) have latent autoimmune diabetes in adults (LADA) and may show different clinical characteristics than those with Type 2 DM. We aimed to determine the ratio and clinical features of LADA in patients with diagnosed initially as Type 2 DM. We measured glutamic acid decarboxylase antibodies (GADA) in 54 patients, diagnosed clinically with Type 2 DM. Of 54 patients, 17 (31%) were GADA positive. GADA-positive patients had significantly earlier diabetes onset age (P<.001), lower BMI (P<.05), and lower serum C-peptide value (P<.001) than did those who were GADA negative. A higher proportion of the GADA-positive patients were receiving insulin therapy (P<.01). With respect to the duration of DM, familial history of DM, and the levels of blood pressures, fasting plasma glucose, and HbA1c, there was no difference between the two groups. Nephropathy and retinopathy were more frequent in GADA-positive than in GADA-negative patients. The prevalence of neuropathy was comparable between the two groups. GADA was negatively associated with BMI, C-peptide levels, and diabetes-onset age, but positively related to retinopathy, nephropathy, and insulin treatment. This study indicated that the important portion of the patients who were initially diagnosed as Type 2 DM may have LADA. In Type 2 diabetic patients who have lower BMI and diagnosis of diabetes in relatively younger age, the possibility of LADA should be taken into consideration. The higher prevalence of nephropathy and retinopathy in GADA-positive patients also suggests the importance of early diagnosis and strict metabolic control in these patients.

IRIS II study: the IRIS II score--assessment of a new clinical algorithm for the classification of insulin resistance in patients with Type 2 diabetes

AIMS

With the increasing availability of new drugs for the treatment of insulin resistance in patients with Type 2 diabetes, simple methods for their identification is an important challenge. The aim of our study was to compute a new algorithm for estimating insulin resistance in a routine clinical setting.

METHODS

Clinical data and blood samples were collected from 4265 Type 2 diabetic patients from 149 clinical sites. A clinical algorithm to estimate insulin resistance was developed by stepwise multiple regression analysis. The new generated score was compared with the HOMAIR-score, calculated from fasting insulin and glucose levels measured in a central laboratory. In a subgroup of 48 patients, the score was verified against a frequently sampled intravenous glucose tolerance test with subsequent modified minimal model analysis according to Bergman.

RESULTS

Multiple regression analysis revealed fasting blood glucose, BMI, triglycerides and HDL as the most powerful predictors of insulin resistance which were used for further computation of the IRIS II score. A significant overall correlation was found between the HOMAIR-score and the new clinical IRIS II score (r = 0.42; P < 0.0001). Compared with HOMAIR, the new score revealed a specificity of 0.95, a sensitivity of 0.34 and a positive predictive value of 0.95. This was in good agreement with the subset analysis of the intravenous glucose tolerance test, where a sensitivity of 0.37 and a specificity of 0.85 of the IRIS II score was calculated. Patients with insulin resistance according to the IRIS II score revealed an increased odds ratio for overall vascular complications (1.28; 1.11-1.46; P < 0.001).

CONCLUSIONS

The new IRIS II score can identify insulin resistance in Type 2 diabetic patients with high predictive value and high specificity.

Asymptomatic cytomegalovirus infection is associated with increased risk of new-onset diabetes mellitus and impaired insulin release after renal transplantation

AIMS/HYPOTHESIS

The human cytomegalovirus (CMV) may increase the risk of diabetes mellitus, but the literature is scarce. The present study was designed to test the hypothesis that asymptomatic CMV infection is associated with increased risk of new-onset diabetes after renal transplantation, and to assess the impact of asymptomatic CMV infection on OGTT-derived estimates of insulin release and insulin action.

METHODS

A total of 160 consecutive non-diabetic renal transplant recipients on cyclosporine (Sandimmun Neoral)-based immunosuppression were closely monitored for CMV infection during the first 3 months after transplantation. All patients underwent a 75-g OGTT at 10 weeks. Excluded from the analyses were 36 patients with symptomatic CMV infection (disease).

RESULTS

The incidence of new-onset diabetes was 6% in a control group of recipients without CMV infection (4/63) and 26% in the group with asymptomatic CMV infection (16/61). Asymptomatic CMV infection was associated with a significantly increased risk of new-onset diabetes (adjusted odds ratio: 4.00; 95% CI: 1.19 to 13.43, p=0.025). The group of patients with CMV infection had a significantly lower median insulin release than controls.

CONCLUSIONS/INTERPRETATION

Our findings support the hypothesis that asymptomatic CMV infection is associated with increased risk of new-onset post-transplant diabetes mellitus, and suggest that impaired insulin release may involve one pathogenetic mechanism.

Oxidative stress in Alzheimer's and vascular dementias: masking of the antioxidant profiles by a concomitant Type II diabetes mellitus condition

Oxidative stress is associated with Alzheimer's (DAT) and vascular (VD) dementias, as well as Type II diabetes mellitus (DIAB) and affected by hypoglycemic therapy. The population (n = 122; males = 60; mean age = 72.57 +/- 7.06) consisted of controls (CTR), DAT and VD patients, with (DAT + DIAB, VD + DIAB) and without concomitant DIAB, resulting in six groups where the antioxidant profile was determined: copper-zinc superoxide dismutase (SOD), thiobarbituric acid reactive substances (TBARS), and total antioxidant capacity (TRAP). The results were analyzed using a two-way ANOVA design and Bonferroni statistic. The ANOVAs yielded significant differences between groups for all components of the profile: SOD, p = 0.00000006; TBARS, p = 0.0000012; TRAP, p = 0.0000003. The significance level for comparisons between groups was set at alpha = 0.05. The comparisons DIAB vs. CTR, DAT+DIAB vs. DAT, and DIAB demented vs. DIAB non-demented resulted significant for all variables. VD + DIAB vs. VD resulted significant for all variables except TRAP. The antioxidant profiles of DIAB and CTR are different. The differences cannot be directly related with what is observed in dementias. The differences in profiles of demented and non-demented are somewhat hidden when demented patients are affected by a concomitant DIAB condition and/or hypoglycemic treatment, thus conditioning the diagnostic value for dementias of the profiles.