Adult-onset autoimmune diabetes in Europe is prevalent with a broad clinical phenotype: Action LADA 7

OBJECTIVE

Specific autoantibodies characterize type 1 diabetes in childhood but are also found in adult-onset diabetes, even when initially non-insulin requiring, e.g., with latent autoimmune diabetes (LADA). We aimed to characterize adult-onset autoimmune diabetes.

RESEARCH DESIGN AND METHODS

We consecutively studied 6,156 European diabetic patients attending clinics within 5 years of diagnosis (age range, 30-70 years) examined cross-sectionally clinically and for GAD antibodies (GADA) and antibodies to insulinoma-associated antigen-2 (IA-2A) and zinc-transporter 8 (ZnT8A).

RESULTS

Of 6,156 patients, 541 (8.8%) had GADA and only 57 (0.9%) IA-2A or ZnT8A alone. More autoantibody-positive than autoantibody-negative patients were younger, leaner, on insulin (49.5 vs. 13.2%), and female (P < 0.0001 for each), though LADA patients (9.7% of total) did not show categorically distinct clinical features from autoantibody-negative type 2 diabetes. Similarly, more GADA patients with high (>200 World Health Organization IU) (n = 403) compared with low (n = 138) titer were female, lean, and insulin treated (54.6 vs. 39.7%) (P < 0.02 for each). Autoantibody-positive patients usually had GADA (541 of 598; 90.5%) and had LADA more often than type 1 autoimmune diabetes (odds ratio 3.3).

CONCLUSIONS

Adult-onset autoimmune diabetes emerges as a prevalent form of autoimmune diabetes. Our results indicate that adult-onset autoimmune diabetes in Europe encompasses type 1 diabetes and LADA in the same broad clinical and autoantibody-positive spectrum. At diagnosis, patients with adult-onset autoimmune diabetes are usually non-insulin requiring and clinically indistinguishable from patients with type 2 diabetes, though they tend to be younger and leaner. Only with screening for autoantibodies, especially GADA, can they be identified with certainty.

Tuberculosis diagnostic delay and therapy outcomes of non-national migrants in Tel Aviv, 1998-2008

Non-national migrants have limited access to medical therapy. This study compares diagnostic delay and treatment outcomes of non-insured non-national migrants (NINNM) with insured Israeli citizens (IC) in the Tel Aviv tuberculosis (TB) clinic between 1998 and 2008. Patient delay was the time from symptoms onset to doctor's visit, while system delay was measured from doctor visit to anti-TB therapy administration. We randomly sampled 222 NINNM and 265 IC. NINNM were younger than IC, had lower male to female ratio and fewer smoked. They had less drug/alcohol abuse, more cavitations on chest radiography, longer patient and shorter system delay. Mean patient and system delays of all patients were 25±14 and 79±42 days, respectively. In multivariate analysis, being NINNM, asymptomatic or smoking predicted longer patient delay, while being asymptomatic or having additional co-morbidity predicted longer system delay. Treatment success in sputum smear-positive pulmonary TB NINNM was 81% and 95.7% in IC (p=0.01). Treatment success was not associated with patient or system delay. In multivariate analysis, work security and treatment adherence predicted treatment success. NINNM had longer patient delay and worse therapy outcome, while IC had longer system delay. Both delays should be reduced. NINNM should be informed that TB therapy is free and unlinked with deportation.

Tuberculosis diagnostic delay and therapy outcomes of non-national migrants in Tel Aviv, 1998-2008

Non-national migrants have limited access to medical therapy. This study compares diagnostic delay and treatment outcomes of non-insured non-national migrants (NINNM) with insured Israeli citizens (IC) in the Tel Aviv tuberculosis (TB) clinic between 1998 and 2008. Patient delay was the time from symptoms onset to doctor's visit, while system delay was measured from doctor visit to anti-TB therapy administration. We randomly sampled 222 NINNM and 265 IC. NINNM were younger than IC, had lower male to female ratio and fewer smoked. They had less drug/alcohol abuse, more cavitations on chest radiography, longer patient and shorter system delay. Mean patient and system delays of all patients were 25 ± 14 and 79 ± 42 days, respectively. In multivariate analysis, being NINNM, asymptomatic or smoking predicted longer patient delay, while being asymptomatic or having additional co-morbidity predicted longer system delay. Treatment success in sputum smear-positive pulmonary TB NINNM was 81% and 95.7% in IC (p=0.01). Treatment success was not associated with patient or system delay. In multivariate analysis, work security and treatment adherence predicted treatment success. NINNM had longer patient delay and worse therapy outcome, while IC had longer system delay. Both delays should be reduced. NINNM should be informed that TB therapy is free and unlinked with deportation.

Serum adipokines as biomarkers of beta-cell function in patients with type 1 diabetes: positive association with leptin and resistin and negative association with adiponectin

BACKGROUND

We investigated the adipokines adiponectin, leptin and resistin as serum biomarkers of beta-cell function in patients with type 1 diabetes.

METHODS

One hundred and eighteen patients with type 1 diabetes (20.3 ± 7.5 years) diagnosed <5 years underwent standardized mixed meal test (MMTT) for 2 h. Systemic concentrations of C-peptide, adiponectin, leptin and resistin obtained during MMTT were measured and compared between patient groups by multiple regression analysis.

RESULTS

Patients were divided by their adipokine levels in subgroups above or below the median level ('high versus low'). High adiponectin levels (>10.6 µg/mL) were associated with lower C-peptide compared to the low adiponectin subgroup (p < 0.03). Increased leptin or resistin concentrations associated positively with beta-cell function even after adjustment for metabolic confounders (p < 0.04). The described associations between adipokines and C-peptide concentrations persisted in Spearman correlation tests (p < 0.05). Serum adipokines fell during MMTT (p < 0.05).

CONCLUSIONS

Serum adipokine levels differentially correlate with beta-cell function in type 1 diabetes independent of BMI or metabolic control. Serum adipokines should be investigated as biomarkers of beta-cell function in prospective studies and intervention trials in type 1 diabetes.

Resistance to diabetes-promoting lifestyle factors -- what is the mechanism?

Not all people exposed to diabetes-promoting lifestyle factors progress to overt type 2 diabetes. The emerging concept of hormesis provides an explanation for the resistance to metabolic stress. Hormesis requires limited stress or damage which elicits an adaptive repair and protective response which renders the organism resistant to further metabolic stress.

Increased serum concentrations of adhesion molecules but not of chemokines in patients with Type 2 diabetes compared with patients with Type 1 diabetes and latent autoimmune diabetes in adult age: action LADA 5

AIMS

Systemic concentrations of adhesion molecules and chemokines are associated with increased risk of cardiovascular complications. We compared these factors between patients with Type 2 diabetes vs. Type 1 diabetes or latent autoimmune diabetes in adults.

METHODS

Serum concentrations of adhesion molecules sE-selectin, sICAM-1 and sVCAM-1, and chemokines CCL2, CCL3 and CCL4 were measured in 61 patients with latent autoimmune diabetes in adults, 90 with Type 1 diabetes, 465 with Type 2 diabetes and in 41 control subjects, using multiple regression models to adjust for possible confounders.

RESULTS

Patients with Type 2 diabetes exhibited greater concentrations of adhesion molecules (P < 0.02) than those with Type 1 diabetes, latent autoimmune diabetes in adults and control subjects. These differences persisted upon adjustments for age, sex, BMI, blood pressure and diabetes duration (P < 0.04). Higher BMI positively correlated with concentrations of adhesion molecules in all subjects (P < 0.0001). Concentrations of sE-selectin positively related to diastolic (β = 0.31) and systolic (β = 0.28) blood pressure in the adjusted model (P < 0.04). Concentrations of the chemokines, CCL2 and CCL4, did not differ between groups, while CCL3 was higher in patients with latent autoimmune diabetes in adults and Type 1 diabetes than in those with Type 2 diabetes and control subjects (P < 0.05).

CONCLUSIONS

Systemic concentrations of adhesion molecules, but not chemokines, relate to cardiovascular risk factors, but remain higher after adjustments in Type 2 diabetes, suggesting a diabetes-type specific effect without difference between latent autoimmune diabetes in adults and Type 1 diabetes, despite their dissimilar phenotype.

[The Da Vinci Medical-mental motivation program for supporting lifestyle changes in patients with type 2 diabetes]

BACKGROUND AND OBJECTIVE

Healthy diet and physical activity can improve metabolic control in patients with type 2 diabetes mellitus. However, lifestyle change without external help is difficult: an alteration of mental attitude is necessary to achieve long-term success. A computer-based motivational program ("Da Vinci") has been developed to help patients to change their mental attitudes and beliefs.

METHODS

Patients with type 2 diabetes were supervised by psychological trainers in four sessions at ten study centers. The interactive computer program allowed for identification of motivation restraints and overcoming them. Parameters of carbohydrate metabolism were measured at the beginning and end of the three-months program as well as three and six months after end of program.

RESULTS

All participants (n = 61) developed a positive attitude towards the range of their action and by themselves changed their lifestyle. After three months their weight (-4.6 kg; p < 0.0001), body mass index (-1.1 kg/m2; p < 0.0001), waist circumference (-3.5 cm; p < 0.0001), HbA1c (-0.6 %; p < 0.0001), triglycerides (-31.1 mg/dl; p = 0.033), systolic (-4.0 mmHg; p = 0.005) and diastolic blood pressure (-3.0 mmHg; p = 0.006) had been reduced. Short duration of diabetes and high baseline HbA1c values were predictive for successful HbA1c reduction. Three and six months after end of the program participants were able to maintain or even augment achieved improvements.

CONCLUSION

During the motivational program, which is intended to alter mental attitude and beliefs, but not to teach knowledge about diabetes, participants were able to significantly improve their metabolic control. As these improvements were maintained long-term, this points to sustainable lifestyle change.

Cellular interferon-γ and interleukin-13 immune reactivity in type 1, type 2 and latent autoimmune diabetes: action LADA 6

OBJECTIVE

Type 1 diabetes and latent autoimmune diabetes in adults (LADA) are thought to result from immune-mediated β-cell destruction. It remains unclear why LADA is clinically less severe compared to type 1 diabetes. This study aimed to compare the pro-inflammatory (interferon-γ, IFN-γ) and anti-inflammatory (interleukin-13, IL-13) T-cell responses in humans with LADA and type 1 diabetes.

RESEARCH DESIGN AND METHODS

IFN-γ and IL-13 T-cell responses to a panel of 16 (auto)-antigens were tested using an enzyme linked immune-spot technique and peripheral T-cells from 35 patients with type 1 diabetes, 59 patients with type 2 diabetes, 23 LADA patients, and 42 control subjects.

RESULTS

LADA and type 1 diabetes patients did not display any statistically significant differences in the frequency of IFN-γ or IL-13 responses to auto-antigenic stimuli, positive control or mitogen. Overall very low T cell reactivity to autoantigens was detected in all groups. IL-13 responses but not IFN-γ responses to recall antigen tetanus toxoid were higher in healthy control subjects compared to patients with type 1 or type 2 diabetes or LADA (P<0.05). Diabetes, independent of type, was associated with weaker response to recall antigen tetanus toxoid.

CONCLUSIONS

LADA patients are indistinguishable from type 1 diabetes patients for cellular IFN-γ and IL-13 responses upon mitogen and recall antigen stimulation. These results extend previous findings showing that systemic cytokine/chemokine and humoral responses in type 1 diabetes and LADA are similar.

Resistance to type 2 diabetes mellitus: a matter of hormesis?

Type 2 diabetes mellitus is characterized by subclinical systemic inflammation and impaired regulation of blood glucose levels. Interestingly, impairment of glycemic control occurs despite substantial insulin secretion early in the course of this disease. Dysfunction of several organs (including pancreatic islets, liver, skeletal muscle, adipose tissue, gut, hypothalamus and the immune system) has been implicated in the pathogenesis of type 2 diabetes mellitus. However, diabetes-promoting lifestyle factors do not inevitably cause disease in all persons exposed. Hence, defense mechanisms must exist that can keep the detrimental influence of these risk factors at bay. Hormesis describes the phenomenon that exposure to a mild stressor confers resistance to subsequent, otherwise harmful, conditions of increased stress. This Review discusses the emerging concept that the effectiveness of an adaptive (hormetic) response to detrimental lifestyle factors determines the extent of protection from progression to type 2 diabetes mellitus. Further analysis of these protective hormetic responses at the molecular level should help to identify novel targets for preventive or therapeutic intervention in patients at risk of developing type 2 diabetes mellitus or those with overt disease.

Association of the FTO gene variant (rs9939609) with cardiovascular disease in men with abnormal glucose metabolism--the Finnish Diabetes Prevention Study

BACKGROUND AND AIM

The common single nucleotide polymorphism (SNP) in the FTO (fat mass and obesity associated) gene has been consistently associated with an increased risk of obesity. We investigated whether the SNP rs9939609 (T/A) of the FTO is associated with risk factors of cardiovascular diseases (CVD), including serum levels of C - reactive protein (CRP), the chemokine RANTES (Regulated on Activation, Normal T Cell Expressed and Secreted; CCL5), and serum and lipoprotein lipids in the Finnish Diabetes Prevention Study (DPS). Furthermore, we examined whether the rs9939609 increased the CVD risk in the DPS and if these results could be replicated in a larger cross-sectional population-based random sample of Finnish men (the METSIM).

METHODS AND RESULTS

In the DPS, altogether 490 (BMI≥25kg/m(2)) subjects with impaired glucose tolerance were genotyped for rs9939609. Cardiovascular morbidity and mortality data were collected during the median follow-up of 10.2 years. The replication study was a population-based cross-sectional study of 6214 men. In the DPS, the AA genotype of rs9939609 was associated, independently of BMI, with increased RANTES (p=0.002) and decreased HDL cholesterol concentrations (p=0.007) in men. During the follow-up, the AA genotype was associated with an adjusted 2.09-fold risk (95% CI 1.17-3.73, p=0.013) of CVD in men. In the METSIM Study, the association with a history of myocardial infarction was replicated in the subgroup of men with type 2 diabetes.

CONCLUSION

We suggest that the variation in the FTO gene may contribute to the development of CVD in men with an abnormal glucose metabolism.

Pro- and anti-inflammatory cytokines in latent autoimmune diabetes in adults, type 1 and type 2 diabetes patients: Action LADA 4

AIMS/HYPOTHESIS

Systemic pro- and anti-inflammatory cytokines are associated with both type 1 and type 2 diabetes, while their role in latent autoimmune diabetes in adults (LADA) is unclear. Therefore, we compared cytokine concentrations in patients with LADA, type 1 or type 2 diabetes and healthy individuals to test the hypothesis that differences of cytokine concentrations between all groups are attributable to diabetes type and BMI.

METHODS

The pro-inflammatory cytokines IL-6 and TNF-α, and the anti-inflammatory cytokines IL-1 receptor antagonist (IL-1RA) and IL-10 were measured in 90 participants with type 1 diabetes, 61 with LADA, 465 with type 2 diabetes and 41 control participants using multiple regression models adjusted for BMI, sex, age, blood pressure and diabetes duration.

RESULTS

Patients with type 2 diabetes had higher concentrations of systemic IL-1RA, IL-6 and TNF-α cytokines than patients with either LADA or type 1 diabetes (p < 0.0001 for all differences). Cytokine concentrations in controls were lower than those in all diabetes types (p < 0.04). Increased BMI was positively associated with higher systemic cytokine concentrations in all diabetes types (p < 0.0001). Despite the association of cytokines with anthropometric data, differences between diabetes forms persisted also after adjusting analysis for the confounders BMI, age, sex, disease duration and blood pressure (p < 0.04).

CONCLUSIONS/INTERPRETATION

Although body mass associates positively with pro- and anti-inflammatory cytokine levels, patients with type 2 diabetes have higher cytokine levels independent of the prevailing BMI. LADA and type 1 diabetes could not be distinguished by systemic cytokines.

Residual beta cell function in newly diagnosed type 1 diabetes after treatment with atorvastatin: the Randomized DIATOR Trial

Background

Recent evidence suggests that the lipid-lowering agent atorvastatin is also a potent immunomodulator. The aim of this study was to investigate the possible effect of atorvastatin on the decline of residual beta cell function in recent-onset type 1 diabetes.

Methods and Findings

The randomised placebo-controlled Diabetes and Atorvastatin (DIATOR) Trial included 89 patients with newly diagnosed type 1 diabetes and islet autoantibodies (mean age 30 years, 40% females), in 12 centres in Germany. Patients received placebo or 80 mg/d atorvastatin for 18 months. As primary outcome stimulated serum C-peptide levels were determined 90 min after a standardized liquid mixed meal. An intent-to-treat analysis was performed. Fasting and stimulated C-peptide levels were not significantly different between groups at 18 months. However, median fasting serum C-peptide levels dropped from baseline to 12 and 18 months in the placebo group (from 0. 34 to 0.23 and 0.20 nmol/l, p<0.001) versus a nonsignificant decline in the atorvastatin group (from 0.34 to 0.27 and 0.30 nmol/l, ns). Median stimulated C-peptide concentrations declined between baseline and 12 months (placebo from 0.89 to 0.71 nmol/l, atorvastatin from 0.88 to 0.73 nmol/l, p<0.01 each) followed by a major loss by month 18 in the placebo group (to 0.48 nmol/l, p = 0.047) but not in the atorvastatin group (to 0.71 nmol/l, ns). Median levels of total cholesterol and C-reactive protein decreased in the atorvastatin group only (p<0.001 and p = 0.04). Metabolic control was similar between groups.

Conclusions

Atorvastatin treatment did not significantly preserve beta cell function although there may have been a slower decline of beta-cell function which merits further study.

Trial Registration

ClinicalTrials.gov NCT00974740

High affinity binding of hydrophobic and autoantigenic regions of proinsulin to the 70 kDa chaperone DnaK

BACKGROUND

Chaperones facilitate proper folding of peptides and bind to misfolded proteins as occurring during periods of cell stress. Complexes of peptides with chaperones induce peptide-directed immunity. Here we analyzed the interaction of (pre)proinsulin with the best characterized chaperone of the hsp70 family, bacterial DnaK.

RESULTS

Of a set of overlapping 13-mer peptides of human preproinsulin high affinity binding to DnaK was found for the signal peptide and one further region in each proinsulin domain (A- and B-chain, C-peptide). Among the latter, peptides covering most of the B-chain region B11-23 exhibited strongest binding, which was in the range of known high-affinity DnaK ligands, dissociation equilibrium constant (K'd) of 2.2 ± 0.4 μM. The B-chain region B11-23 is located at the interface between two insulin molecules and not accessible in insulin oligomers. Indeed, native insulin oligomers showed very low DnaK affinity (K'd 67.8 ± 20.8 μM) whereas a proinsulin molecule modified to prevent oligomerization showed good binding affinity (K'd 11.3 ± 7.8 μM).

CONCLUSIONS

Intact insulin only weakly interacts with the hsp70 chaperone DnaK whereas monomeric proinsulin and peptides from 3 distinct proinsulin regions show substantial chaperone binding. Strongest binding was seen for the B-chain peptide B 11-23. Interestingly, peptide B11-23 represents a dominant autoantigen in type 1 diabetes.

Effects of coffee consumption on subclinical inflammation and other risk factors for type 2 diabetes: a clinical trial

BACKGROUND

Coffee consumption is associated with a decreased risk of type 2 diabetes. Suggested mechanisms underlying the association have included attenuation of subclinical inflammation and a reduction in oxidative stress.

OBJECTIVE

The aim was to investigate the effects of daily coffee consumption on biomarkers of coffee intake, subclinical inflammation, oxidative stress, glucose, and lipid metabolism.

DESIGN

Habitual coffee drinkers (n = 47) refrained for 1 mo from coffee drinking; in the second month they consumed 4 cups of filtered coffee/d and in the third month 8 cups of filtered coffee/d (150 mL/cup). Blood samples were analyzed by gas chromatography-mass spectrometry, bead-based multiplex technology, enzyme-linked immunosorbent assay, or immunonephelometry.

RESULTS

Coffee consumption led to an increase in coffee-derived compounds, mainly serum caffeine, chlorogenic acid, and caffeic acid metabolites. Significant changes were also observed for serum concentrations of interleukin-18, 8-isoprostane, and adiponectin (medians: -8%, -16%, and 6%, respectively; consumption of 8 compared with 0 cups coffee/d). Serum concentrations of total cholesterol, HDL cholesterol, and apolipoprotein A-I increased significantly by 12%, 7%, and 4%, respectively, whereas the ratios of LDL to HDL cholesterol and of apolipoprotein B to apolipoprotein A-I decreased significantly by 8% and 9%, respectively (8 compared with 0 cups coffee/d). No changes were seen for markers of glucose metabolism in an oral-glucose-tolerance test.

CONCLUSIONS

Coffee consumption appears to have beneficial effects on subclinical inflammation and HDL cholesterol, whereas no changes in glucose metabolism were found in our study. Furthermore, many coffee-derived methylxanthines and caffeic acid metabolites appear to be useful as biomarkers of coffee intake.

The rs1800629 polymorphism in the TNF gene interacts with physical activity on the changes in C-reactive protein levels in the Finnish Diabetes Prevention Study

Physical activity exerts anti-inflammatory effects, but genetic variation may modify its influence. In particular, the rs1800629 single-nucleotide polymorphism (SNP) in the tumor necrosis factor ( TNF) gene and the rs1800795 SNP in the interleukin-6 ( IL6) gene have been found to modify the effect of exercise training on circulating levels of C-reactive protein (CRP) and IL-6, respectively. We assessed whether rs1800629 and rs1800795 modified the effect of moderate-to-vigorous physical activity on changes in serum levels of high-sensitivity CRP and IL-6 in the Finnish Diabetes Prevention Study (DPS). Genotype and 1-year data on changes in physical activity, serum CRP and IL-6 were available for 390 overweight subjects with impaired glucose tolerance. The rs1800629 SNP in TNF interacted with the 1-year change in moderate-to-vigorous physical activity on changes in CRP among those who had high (≥3 mg/L) baseline CRP levels ( P = 0.034 for interaction). Carriers of the GG genotype showed a greater decrease in CRP with increasing physical activity than the individuals with the A allele. No interaction between the rs1800795 SNP in IL6 and changes in moderate-to-vigorous physical activity on the 1-year change in serum IL-6 was found. In conclusion, the rs1800629 SNP in the TNF gene may modify the effect of moderate-to-vigorous physical activity on serum levels of CRP.