Smoking, use of smokeless tobacco, HLA genotypes and incidence of latent autoimmune diabetes in adults.

AIMS/HYPOTHESES: Smoking and use of smokeless tobacco (snus) are associated with an increased risk of type 2 diabetes. We investigated whether smoking and snus use increase the risk of latent autoimmune diabetes in adults (LADA) and elucidated potential interaction with HLA high-risk genotypes. METHODS: Analyses were based on Swedish case-control data (collected 2010-2019) with incident cases of LADA (n=593) and type 2 diabetes (n=2038), and 3036 controls, and Norwegian prospective data (collected 1984-2019) with incident cases of LADA (n=245) and type 2 diabetes (n=3726) during 1,696,503 person-years of follow-up. Pooled RRs with 95% CIs were estimated for smoking, and ORs for snus use (case-control data only). The interaction was assessed by attributable proportion (AP) due to interaction. A two-sample Mendelian randomisation (MR) study on smoking and LADA/type 2 diabetes was conducted based on summary statistics from genome-wide association studies. RESULTS: Smoking (RRpooled 1.30 [95% CI 1.06, 1.59] for current vs never) and snus use (OR 1.97 [95% CI 1.20, 3.24] for ≥15 box-years vs never use) were associated with an increased risk of LADA. Corresponding estimates for type 2 diabetes were 1.38 (95% CI 1.28, 1.49) and 1.92 (95% CI 1.27, 2.90), respectively. There was interaction between smoking and HLA high-risk genotypes (AP 0.27 [95% CI 0.01, 0.53]) in relation to LADA. The positive association between smoking and LADA/type 2 diabetes was confirmed by the MR study. CONCLUSIONS/INTERPRETATION: Our findings suggest that tobacco use increases the risk of LADA and that smoking acts synergistically with genetic susceptibility in the promotion of LADA. DATA AVAILABILITY: Analysis codes are shared through GitHub ( https://github.com/jeseds/Smoking-use-of-smokeless-tobacco-HLA-genotypes-and-incidence-of-LADA ).

A 1-year pilot study of intralymphatic injections of GAD-alum in individuals with latent autoimmune diabetes in adults (LADA) with signs of high immunity: No safety concerns and resemblance to juvenile type 1 diabetes.

AIMS: To test, for the first time in latent autoimmune diabetes in adults (LADA), the effects of autoantigen-specific immunotherapy by intralymphatic administration of aluminium-formulated recombinant human glutamic acid decarboxylase 65 (GAD-alum); specifically, to test if this treatment is safe, to test whether it induces a strong immunological response akin to a similar protocol in type 1 diabetes and to look for associations with preserved beta-cell function. MATERIALS AND METHODS: Three GAD-alum injections, 4 µg each, were administered 1 month apart into an inguinal lymph node in 14 people with newly diagnosed LADA (age 30-62 years) presenting with high levels of antibodies against glutamic acid decarboxylase (GADA). Adverse effects, immunological variables and beta-cell function were monitored, with detailed measurements at 5 and 12 months from baseline. RESULTS: Clinical adverse effects were minor and transient and measured laboratory variables were unaffected. All participants completed the study. Treatment raised levels of GADA, elicited strong effects on reactivity of peripheral blood mononuclear cells to GAD and raised cytokine/chemokine levels. Beta-cell function appeared stable preferentially in the seven participants carrying human leukocyte antigen (HLA) haplotypes DR3DQ2, as assessed by C-peptide glucagon tests (P < 0.05 vs. seven non-carriers). CONCLUSION: Intralymphatic treatment with GAD-alum in LADA is without clinical or other safety concerns over a 12-month period. As in a similar protocol used in type 1 diabetes, treatment exerts a strong immunological impact and is compatible with protection of beta-cell function preferentially in HLA-DR3DQ2 LADA patients. These findings pave the way for a randomized controlled trial in this important subgroup of LADA patients.

Time-dependent effects on circulating cytokines in patients with LADA: A decrease in IL1-ra and IL-1 beta is associated with progressive disease.

BACKGROUND: Cytokines and chemokines participate in autoimmune processes at cellular targets which include insulin-producing beta cells. To which extent such participation is reflected in the circulation has not been conclusively resolved. AIM: We compared the time course of cytokines/chemokines in Latent Autoimmune Diabetes in Adults (LADA) patients heterogeneous for high or low autoimmune activity as determined by levels of antibodies against glutamic acid decarboxylase (GADA). METHODS: Serum samples to be measured were from a two-armed randomized controlled trial (RCT) in 68 LADA patients. The study encompassed 21 months with C-peptide as primary endpoint. We measured 27 immune mediators at baseline, at 9 and at 21 months (end of study). Results of measurements were analyzed by multiple linear regression. RESULTS: At baseline, a high body mass index (BMI) (>26 kg/m2) was associated with elevated levels of the interleukins (IL) IL-1 beta, IL-1ra, IL-2, IL-5, IL-6 and IL-13. Treatment during RCT (sitagliptin vs. insulin) did not affect the time course (21 months) of levels of cytokines/chemokines (by univariate analyses). However, levels of the cytokines IL-1ra and IL-1 beta decreased significantly (p < 0.04 or less) in patients with high vs. low GADA when adjusted for BMI, age, gender (male/female), treatment (insulin/sitagliptin) and study site (Norwegian/Swedish). CONCLUSIONS: In LADA, high levels of GADA, a proxy for high autoimmune activity and linked to a decline in C-peptide, was associated with a decrease of selected cytokines over time. This implies that the decline of IL-1ra and IL-1 beta in the circulation reflects autoimmune activity and beta cell demise in LADA.

Low C-peptide together with a high glutamic acid decarboxylase autoantibody level predicts progression to insulin dependence in latent autoimmune diabetes in adults: The HUNT study.

AIM: To search for risk factors that could predict progression in latent autoimmune diabetes in adults (LADA) and compare them with those for type 2 diabetes. MATERIALS AND METHODS: This study included 175 participants with LADA (autoantibody positive, without insulin treatment ≥1 year after diagnosis) and 2331 participants with type 2 diabetes (autoantibody negative, without insulin treatment ≥1 year after diagnosis) from the HUNT2 and HUNT3 surveys. We used Cox regression models and receiver operating characteristic curve analysis to identify predictive factors for progression to insulin dependency within 10 years. RESULTS: Low C-peptide levels (<0.3 nmol/L) predicted progression to insulin dependency within 10 years in both LADA (hazard ratio [HR] 6.40 [95% CI, 2.02-20.3]) and type 2 diabetes (HR 5.01 [95% CI, 3.53-7.10]). In addition, a high glutamic acid decarboxylase autoantibody (GADA) level (HR 5.37 [95% CI, 1.17-24.6]) predicted progression in LADA. Together, these two factors had a discriminatory power between non-progressors and progressors of area under the curve (AUC) of 0.86 (95% CI, 0.80-0.93). In type 2 diabetes, younger age at diagnosis (<50 years: HR 2.83 [95% CI, 1.56-5.15]; 50-69 years: HR 2.11 [95% CI, 1.19-3.74]), high HbA1c levels (≥53 mmol/mol, HR 2.44 [95% CI, 1.72-3.46]), central obesity (HR 1.65 [95% CI, 1.06-2.55]) and a body mass index of more than 30 kg/m2 (HR 1.73 [95% CI, 1.23-2.41]) were independent predictors. Together with C-peptide they reached an AUC of 0.79 (95% CI, 0.76-0.82). CONCLUSION: Factors predicting progression to insulin dependence are partly similar and partly dissimilar between LADA and type 2 diabetes. A constellation of low C-peptide and high GADA levels identifies LADA patients who are probable to progress to insulin dependence.

The association of basal insulin treatment versus standard care with outcomes in anti-GAD positive and negative subjects: A post-hoc analysis of the ORIGIN trial.

We compared cardiovascular and other outcomes in patients with dysglycaemia with or without anti-glutamic acid dehydrogenase (GAD) antibodies participating in the Outcome Reduction with Initial Glargine Intervention (ORIGIN) trial. Of the 12 537 participants, 8162 had anti-GAD measured at baseline and 267 were anti-GAD positive. The effects of insulin glargine versus standard care and of n-3 fatty acids supplements versus placebo were compared by testing the interaction of the treatment effects and anti-GAD status. The effect of glargine on development of new diabetes was assessed in participants without previous diabetes at baseline. The overall incidence of outcomes did not differ between anti-GAD positive and anti-GAD negative subjects. The incidence of the composite of cardiovascular death, non-fatal myocardial infarction, or non-fatal stroke did not differ between anti-GAD positive participants randomized to insulin glargine or to standard care, with a hazard ratio (HR) (95% confidence interval [CI]) of 0.80 (0.44-1.44) or in anti-GAD negative participants with a HR of 1.07 (0.96-1.20) (P for interaction = 0.20).

Investigating optimal ß-cell-preserving treatment in latent autoimmune diabetes in adults: Results from a 21-month randomized trial.

AIMS: To compare outcomes of glucagon-stimulated C-peptide tests (GSCTs) in people with latent autoimmune diabetes in adults (LADA) after a 21-month intervention with either insulin or the dipeptidyl peptidase-4 inhibitor sitagliptin. RESEARCH DESIGN AND METHODS: We included 64 glutamic acid decarboxylase (GAD) antibody-positive individuals, who were diagnosed with diabetes <3 years before the study, aged 30 to 70 years, and without clinical need for insulin treatment. We stratified participants by age and body mass index (BMI) and evaluated ß-cell function by GSCT after a 48-hour temporary withdrawal of study medication. RESULTS: Age at randomization (mean 53 years), BMI (mean 27 kg/m2 ) and metabolic markers were similar between treatment arms. Glycated haemoglobin concentrations during intervention did not differ between arms. Fasting C-peptide concentrations after the intervention were similar, as were stimulated C-peptide levels (0.82 ± 0.63 nmol/L after insulin, 0.82 ± 0.46 nmol/L after sitagliptin; nonsignificant). Autoimmunity in the study population (estimated from GAD antibody titres and positivity/no positivity for zinc transporter 8 and islet antigen 2 antibodies) affected the evolution of the GSCT results significantly, which deteriorated in participants with high but not in those with low autoimmunity. Adjustment using analysis of covariance for the degree of autoimmunity did not alter the findings of no difference between treatment arms. CONCLUSIONS: ß-cell function after intervention was similar in patients with insulin- and sitagliptin-treated LADA, regardless of the strength of autoimmunity. Further, participants with low levels of GAD antibodies did not experience progressive deterioration of ß-cell function over a 21-month period. Taken together, these findings could be useful for clinicians' choices of treatment in people with LADA.

Overweight, obesity and the risk of LADA: results from a Swedish case-control study and the Norwegian HUNT Study.

AIMS/HYPOTHESIS: Excessive weight is a risk factor for type 2 diabetes, but its role in the promotion of autoimmune diabetes is not clear. We investigated the risk of latent autoimmune diabetes in adults (LADA) in relation to overweight/obesity in two large population-based studies. METHODS: Analyses were based on incident cases of LADA (n = 425) and type 2 diabetes (n = 1420), and 1704 randomly selected control participants from a Swedish case-control study and prospective data from the Norwegian HUNT Study including 147 people with LADA and 1,012,957 person-years of follow-up (1984-2008). We present adjusted ORs and HRs with 95% CI. RESULTS: In the Swedish data, obesity was associated with an increased risk of LADA (OR 2.93, 95% CI 2.17, 3.97), which was even stronger for type 2 diabetes (OR 18.88, 95% CI 14.29, 24.94). The association was stronger in LADA with low GAD antibody (GADA;

Elevations of metabolic risk factors 20 years or more before diagnosis of type 2 diabetes: Experience from the AMORIS study.

AIMS: To describe trajectories for metabolic risk factors for type 2 diabetes (T2D) up to 25 years prior to diagnosis and to estimate the absolute 20-year risk for T2D based on a simple set of commonly measured key risk factors. METHODS: From the Swedish AMORIS cohort we included 296 428 individuals with data on fasting glucose obtained in health examinations during 1985-1996 (baseline period). All participants were followed until 2012 for development of incident T2D. The 20-year T2D risk based on age, sex, body mass index (BMI), fasting glucose and triglycerides was estimated. Trajectories for biomedical risk factors of T2D starting from >20 years before diagnosis and including fasting glucose, triglycerides and BMI were evaluated according to yearly means for cases and controls. RESULTS: We identified 28 244 new T2D cases during the study period, with an average 20-year risk of 8.1%. This risk was substantially increased in overweight and obese participants and those with elevated fasting glucose and triglyceride levels, in both men and women. T2D cases had higher mean BMI and fasting glucose and triglyceride levels compared with controls >20 years before diagnosis and the difference in fasting glucose levels increased over time. CONCLUSIONS: Development of T2D is associated with subtle elevations in glucose and lipid levels >20 years before diagnosis. This suggests that diabetogenic processes tied to chronic insulin resistance operate for decades prior to the development of T2D. A simple risk classification can help in early identification of individuals who are at increased risk.

Hyperoxia inhibits glucose-induced insulin secretion and mitochondrial metabolism in rat pancreatic islets.

Isolated pancreatic islets containing the insulin-producing beta cells are devoid of circulation. They may therefore experience hypoxia with possible negative effects on beta cell function and survival. We investigated (1) whether hyperoxia in vitro would be beneficial by counteracting putative effects of lost circulation and, further, (2) whether previous hyperoxia would attenuate the impact of subsequently induced severe hypoxia. Islets from Sprague-Dawley rats were exposed to 95% O2 for 18 h. This hyperoxic exposure diminished glucose-induced insulin secretion by 47% and inhibited oxygen consumption by 39-41%. Mitochondrial complexes I-III were decreased by 29-37%. Negative effects on insulin secretion and complexes III and IV waned after a 22 h period of normoxia following hyperoxia whereas complexes I and II were still diminished, ROS production was increased and rates of apoptosis tended to be increased (P=0.07). The effects of previous hyperoxia on susceptibility to damage by subsequent hypoxia were tested after 5.5h of 0.8% O2. Previous hyperoxia did not affect hypoxia-induced enhancement of HIF-1 alpha but modestly and significantly attenuated hypoxia-induced decreases in insulin contents. We conclude that hyperoxia exerts largely negative effects on beta cells, effects which are functional and possibly also toxic. A paradoxical positive finding (attenuation of hypoxia-induced effects) could be secondary to a protective effect of the hyperoxia-induced reduction of oxidative metabolism.

NEFA Dynamics in Adults With Severe Obesity and Insulin Resistance: No Coupling to the rs9939609 FTO Risk Allele.

Context: The FTO gene is highly expressed in adipose tissues; however, whether nonesterified fatty acids (NEFA) dynamics are impacted by FTO has not been rigorously tested for in a uniformly obese study population comprising both sexes. Objective: To test for associations of the rs9939609 FTO risk allele with NEFA suppression. Methods: We investigated 97 subjects with severe obesity but without diabetes, having genotype TT (n = 32), AT (n = 31), or AA (n = 34) in a cross-sectional observation study. NEFA suppression was assessed from a low-dose hyperinsulinemic euglycemic clamp with glucose-tracer as well as from the response to a standardized meal. Insulin sensitivity was assessed by hepatic and total insulin sensitivity measurements in the clamp and by the Matsuda index during the meal. Variables of possible importance for NEFA dynamics were primarily assessed by linear regression. Results: No genotype associations with fasting or suppressed NEFA were found, whether in the clamp or meal situation (P > .7 for all comparisons). Independent of genotype, higher fasting concentrations of NEFA and larger NEFA suppression were found in female compared with male subjects. Fasting NEFA or degree of suppression were not associated with total fat mass or body mass index. The respiratory quotient was negatively associated with NEFA suppression. Conclusion: In a gender-mixed adult population of obese individuals, an FTO obesity-risk allele did not affect fasting NEFA nor suppression thereof. These negative results on NEFA dynamics appear strengthened by the documentation of gender influence and associations with parameters reflective of insulin resistance.

Exploring Dietary Intake in Adults with Severe Obesity and Associations with the FTO rs9939609 Genotypes.

Background: Few have studied the associations between rs9939609 genotypes in the obesity candidate locus FTO and energy and nutrient intakes and meal frequencies in adults with severe obesity. We are unaware of studies that have assessed adherence to key dietary recommendations in this population, at least in Norway. Increased knowledge of genotype associations with dietary factors could improve personalized obesity therapy. Objectives: The present study aimed to explore how the rs9939609 genotypes associate with dietary variables and adherence to key dietary recommendations in a sample of adults with severe obesity. Methods: A cross-sectional observation study designed to have similar numbers of participants with genotypes TT, AT, and AA included 100 patients (70% women) with median (25th, 75th percentile) age 42 (32, 50) y and BMI 42.8 (39.5, 46.4) kg/m2. We assessed intakes of food groups, energy, and macro- and micronutrients from three 24-h dietary recalls and meal frequencies. Genotype associations were analyzed using regression analyses. Reported intakes were evaluated against national diet recommendations. Results: Using a significance level of 0.01, we found no genotype associations with energy intake, energy density, adherence to recommendations, or meal frequency but tendencies of associations with energy adjusted protein intake (AA > AT, P = 0.037; AT > TT, P = 0.064), food groups milk and cream (AT > TT, P = 0.029), and Mixed dishes (AA > TT, P = 0.039). Few participants complied with recommendations for intakes of whole grains (21%), fruits and vegetables (11%), and fish (37%); however, 67% followed the recommendation to limit added sugar. Less than 20% had recommended intakes of vitamin D and folate. Conclusions: In our patients with severe obesity, we found tendencies of associations between the FTO rs9939609 genotypes and diet but no significant associations at the 0.01 level and below. Few met key food-based diet recommendations, suggesting that the food habits in this population pose an increased risk of nutrient deficiencies. Curr Dev Nutr 2023;xx:xx.

Incidence of LADA and Type 2 Diabetes in Relation to Tobacco Use and Genetic Susceptibility to Type 2 Diabetes and Related Traits: Findings From a Swedish Case-Control Study and the Norwegian HUNT Study.

OBJECTIVE: Smoking and Swedish smokeless tobacco (snus) are associated with latent autoimmune diabetes in adults (LADA) and type 2 diabetes (T2D). Our aim was to investigate whether genetic susceptibility to T2D, insulin resistance (IR), and insulin secretion (IS) aggravate these associations. RESEARCH DESIGN AND METHODS: We used data from two population-based Scandinavian studies with case subjects with LADA (n = 839) and T2D (n = 5,771), matched control subjects (n = 3,068), and 1,696,503 person-years at risk. Pooled, multivariate relative risks (RR) with 95% CI were estimated for smoking/genetic risk scores (T2D-GRS, IS-GRS, and IR-GRS), and ORs for snus or tobacco/GRS (case-control data). We estimated additive (proportion attributable to interaction [AP]) and multiplicative interaction between tobacco use and GRS. RESULTS: The RR of LADA was elevated in high IR-GRS heavy smokers (≥15 pack-years; RR 2.01 [CI 1.30, 3.10]) and tobacco users (≥15 box/pack-years; RR 2.59 [CI 1.54, 4.35]) compared with low IR-GRS individuals without heavy use, with evidence of additive (AP 0.67 [CI 0.46, 0.89]; AP 0.52 [CI 0.21, 0.83]) and multiplicative (P = 0.003; P = 0.034) interaction. In heavy users, there was additive interaction between T2D-GRS and smoking, snus, and total tobacco use. The excess risk conferred by tobacco use did not differ across GRS categories in T2D. CONCLUSIONS: Tobacco use may confer a higher risk of LADA in individuals with genetic susceptibility to T2D and insulin resistance, whereas genetic susceptibility does not seem to influence the increased T2D incidence associated with tobacco use.

Marked over expression of uncoupling protein-2 in beta cells exerts minor effects on mitochondrial metabolism.

Evidence is conflicting as to the impact of elevated levels of uncoupling protein-2 (UCP-2) on insulin-producing beta cells. Here we investigated effects of a fourfold induction of UCP-2 protein primarily on mitochondrial parameters and tested for replication of positive findings at a lower level of induction. We transfected INS-1 cells to obtain a tet-on inducible cell line. A 48 h exposure to 1 µg/ml of doxycycline (dox) induced UCP-2 fourfold (424 ± 113%, mean±SEM) and 0.1 µg/ml twofold (178 ± 29%, n=3). Fourfold induced cells displayed normal viability (MTT, apoptosis), normal cellular insulin contents and, glucose-induced insulin secretion (+27 ± 11%) as well as D-[U-(14)C]-glucose oxidation (+5 ± 9% at 11 mM glucose). Oxidation of [1-(14)C]-oleate was increased from 4088 to 5797 fmol/µg prot/2h at 3.3mM glucose, p<0.03. Oxidation of L-[(14)C(U)]-glutamine was unaffected. Induction of UCP-2 did not significantly affect measures of mitochondrial membrane potential (Rhodamine 123) or mitochondrial mass (Mitotracker Green) and did not affect ATP levels. Oligomycin-inhibited oxygen consumption (a measure of mitochondrial uncoupling) was marginally increased, the effect being significant in comparison with dox-only treated cells, p<0.05. Oxygen radicals, assessed by dichlorofluorescin diacetate, were decreased by 30%, p<0.025. Testing for the lower level of UCP-2 induction did not reproduce any of the positive findings. A fourfold induction of UCP-2 was required to exert minor metabolic effects. These findings question an impact of moderately elevated UCP-2 levels in beta cells as seen in diabetes.

High consumption of smokeless tobacco ("snus") predicts increased risk of type 2 diabetes in a 10-year prospective study of middle-aged Swedish men.

AIMS: Cigarette smoking increases the risk of type 2 diabetes (T2D). In Sweden and the US, people shift from smoking cigarettes to smokeless tobacco, i.e. oral moist snuff, "snus", to attain harm-reduction. There are limited and conflicting data as to whether snus increases the risk of T2D. The present study investigated if snus use predicts the risk of T2D incidence. METHODS: This is a prospective population-based study where middle-aged Swedish men (n=2,383), without previously diagnosed T2D, were investigated with oral glucose tolerance test (OGTT) at baseline in 1992-94 and at follow-up 10 years later. Odds ratios (ORs) for newly diagnosed T2D at follow-up were assessed among those using snus, or cigarettes, at both baseline and follow-up, adjusted for major confounders. RESULTS: The OR for T2D was not significantly increased in the whole group of snus users. However, the risk of diabetes increased with increasing weekly snus consumption; ORs (CIs) for >four boxes of snus/week were 2.1 (CI 0.9-4.9), and for >five boxes/week 3.3 (CI 1.4-8.1). For comparison, men smoking at baseline and still smoking at follow-up had an increased risk of diabetes compared with never smokers, OR 1.5 (CI 0.8-3.0), most evident for those smoking >15 cigarettes per day, OR 2.4 (CI 1.0-5.8). Tobacco use was associated with estimations of low insulin response (OGTT), but not low insulin sensitivity (HOMA). CONCLUSIONS: High consumption of snus, like smoking, predicts risk of developing T2D. This should be considered when seeking harm-reduction by changing from use of cigarettes to snus. T2D risk from tobacco use may be mediated by effects on beta-cell function.

Latent Autoimmune Diabetes in Adults: Background, Safety and Feasibility of an Ongoing Pilot Study With Intra-Lymphatic Injections of GAD-Alum and Oral Vitamin D.

Background: Latent Autoimmune Diabetes in Adults (LADA) constitutes around 10% of all diabetes. Many LADA patients gradually lose their insulin secretion and progress to insulin dependency. In a recent trial BALAD (Behandling Av LADa) early insulin treatment compared with sitagliptin failed to preserve insulin secretion, which deteriorated in individuals displaying high levels of antibodies to GAD (GADA). These findings prompted us to evaluate a treatment that directly affects autoimmunity. Intra-lymphatic GAD-alum treatment has shown encouraging results in Type 1 diabetes patients. We therefore tested the feasibility of such therapy in LADA-patients (the GADinLADA pilot study). Material and Methods: Fourteen GADA-positive (>190 RU/ml), insulin-independent patients 30-70 years old, with LADA diagnosed within < 36 months were included in an open-label feasibility trial. They received an intra-nodal injection of 4 µg GAD-alum at Day 1, 30 and 60 plus oral Vitamin D 2000 U/d from screening 30 days before (Day -30) for 4 months if the vitamin D serum levels were below 100 nmol/L (40 ng/ml). Primary objective is to evaluate safety and feasibility. Mixed Meal Tolerance Test and i.v. Glucagon Stimulation Test at baseline and after 5 and 12 months are used for estimation of beta cell function. Results will be compared with those of the recent BALAD study with comparable patient population. Immunological response is followed. Results: Preliminary results show feasibility and safety, with almost stable beta cell function and metabolic control during follow-up so far (5 months). Conclusions: Intra-lymphatic GAD-alum treatment is an option to preserve beta cell function in LADA-patients. An ongoing trial in 14 LADA-patients show feasibility and safety. Clinical and immunological responses will determine how to proceed with future trials.

Small RNAs are differentially expressed in autoimmune and non-autoimmune diabetes and controls.

Objective: Diabetes is a heterogeneous disease and a precise diagnosis of diabetes subgroups is necessary to initiate proper early treatment and clinical management of the disease. Circulating small RNAs (sRNAs) are potentially diagnostic biomarkers in diseases, including diabetes. Here we aimed to examine whether profiles of circulating sRNAs differed between patients with autoimmune and non-autoimmune diabetes and non-diabetic controls. Design: This cross-sectional case-control study included participants from the third survey of the HUNT study. Methods: We performed sRNA sequencing in serum from adult-onset type 1 diabetes (n = 51), type 2 diabetes (n = 50) and latent autoimmune diabetes in adult (LADA, n = 51), as well as non-diabetic HUNT3 participants as control group (n = 51). Differential expression analysis of the sRNAs was performed in R using limma-voom. Results: We identified differences in sRNA expression between autoimmune (type 1 diabetes and LADA) and non-autoimmune diabetes (type 2 diabetes) and between patients with diabetes and non-diabetic controls. Focusing on miRNA, we identified 10 differentially expressed mature miRNAs and 30 differentially expressed miRNA variants (isomiRs). We also identified significant changes within other sRNA classes, including a pronounced downregulation of a tRNA fragment in patients with diabetes compared to non-diabetic controls. We created cross-validated sRNA signatures based on the significant sRNAs that distinguished patients with diabetes from non-diabetic controls, and autoimmune from non-autoimmune diabetes, with high specificity and sensitivity. sRNA profiles did not distinguish between type 1 diabetes and LADA. Conclusions: Circulating sRNAs are differentially expressed between patients with diabetes and non-diabetic controls and between autoimmune and non-autoimmune diabetes.

Alterations in Biomarkers Related to Glycemia, Lipid Metabolism, and Inflammation up to 20 Years Before Diagnosis of Type 1 Diabetes in Adults: Findings From the AMORIS Cohort.

OBJECTIVE: Type 1 diabetes is described to have an acute onset, but autoantibodies can appear several years preceding diagnosis. This suggests a long preclinical phase, which may also include metabolic parameters. Here we assessed whether elevations in glycemic, lipid, and other metabolic biomarkers were associated with future type 1 diabetes risk in adults. RESEARCH DESIGN AND METHODS: We studied 591,239 individuals from the Swedish AMORIS cohort followed from 1985-1996 to 2012. Through linkage to national patient, diabetes, and prescription registers, we identified incident type 1 diabetes. Using Cox regression models, we estimated hazard ratios for biomarkers at baseline and incident type 1 diabetes. We additionally assessed trajectories of biomarkers during the 25 years before type 1 diabetes diagnosis in a nested case-control design. RESULTS: We identified 1,122 type 1 diabetes cases during follow-up (average age of patient at diagnosis: 53.3 years). The biomarkers glucose, fructosamine, triglycerides, the ratio of apolipoprotein (apo)B to apoA-I, uric acid, alkaline phosphatase, and BMI were positively associated with type 1 diabetes risk. Higher apoA-I was associated with lower type 1 diabetes incidence. Already 15 years before diagnosis, type 1 diabetes cases had higher mean glucose, fructosamine, triglycerides, and uric acid levels compared with control subjects. CONCLUSIONS: Alterations in biomarker levels related to glycemia, lipid metabolism, and inflammation are associated with clinically diagnosed type 1 diabetes risk, and these may be elevated many years preceding diagnosis.

[Declining prevalence of proliferative retinopathy in patients with type 1 diabetes]. / Redusert forekomst av proliferativ retinopati ved type 1-diabetes?

BACKGROUND: It is likely that improved treatment of diabetes during the last decades has led to a declining prevalence of retinopathy. We have assessed whether this is the case for patients with type I diabetes. MATERIAL AND METHODS: Medical records were retrospectively reviewed for all patients who were diagnosed with type 1 diabetes in the periods 1960-1975 (early group) and 1985-1990 (late group) at the diabetes clinic in St. Olavs Hospital (Trondheim). Information on the prevalence of retinopathy ten and 15 years after diabetes onset was obtained from hospital records and private ophthalmologists in Trondheim. RESULTS: 125 patients were identified in the early group and 147 patients in the late group. The prevalence of proliferative retinopathy was higher in the early group than in the late group, both after ten years (4% vs. 0%, p = 0.04) and 15 years (13% vs. 5%, p = 0.04) of diabetes. The prevalence of background retinopathy was not significantly different between the two groups after ten (12% vs. 14%, p = 0.70) or 15 years (29% vs. 24%, p = 0.36) of diabetes. INTERPRETATION: Our results indicate that the prevalence of proliferative retinopathy is decreasing in patients with type 1 diabetes in Norway. Explanations may be improved follow-up and treatment of diabetes and diabetic retinopathy.