Latent autoimmune diabetes in adults (LADA) in Asian and European populations

Association of RPS26 gene polymorphism with different types of diabetes in Chinese individuals

AIMS/INTRODUCTION

Different types of diabetes show distinct genetic characteristics, but the specific genetic susceptibility factors remain unclear. Our study aimed to explore the associations between the ribosomal protein S26 (RPS26) gene rs1131017 polymorphisms and susceptibility to type 1 diabetes mellitus, latent autoimmune diabetes in adults (LADA) and type 2 diabetes mellitus in the Chinese Han population, and their correlations with clinical features.

MATERIALS AND METHODS

Genotyping of the rs1131017 variant was carried out for 1,006 type 1 diabetes mellitus patients, 210 LADA patients, 642 type 2 diabetes mellitus patients and 2,099 control individuals.

RESULTS

We found that the rs1131017 C allele was a risk locus for both type 1 diabetes mellitus and LADA (odds ratio [OR] 1.50, 95% confidence interval [CI] 1.33-1.69, P < 0.001; OR 1.31, 95% CI 1.04-1.64, P = 0.021, respectively). Nevertheless, this association was not found for type 2 diabetes mellitus. Carrying the C allele genotype was associated with a lower postprandial C-peptide for type 1 diabetes mellitus (OR 1.41, 95% CI 1.11-1.80, P = 0.006) and lower fasting C-peptide for LADA (OR 1.55, 95% CI 1.01-2.38, P = 0.047). Interestingly, a lower GC frequency was noted for LADA than for type 1 diabetes mellitus, regardless of classification based on age at diagnosis, C-peptide or glutamic acid decarboxylase antibody positivity.

CONCLUSIONS

The RPS26 polymorphism was associated with susceptibility and clinical characteristics of type 1 diabetes mellitus and LADA in the Chinese population, but was not related to type 2 diabetes mellitus. Thus, it might serve as a novel biomarker for particular types of diabetes.

The worldwide prevalence of latent autoimmune diabetes of adults among adult-onset diabetic individuals: a systematic review and meta-analysis

PURPOSE

The actual global burden of Latent Autoimmune Diabetes of Adults (LADA) remains unknown even though its prevalence is almost equal to the type 1 form of diabetes. Hence the present systematic review and meta-analysis were performed to estimate the prevalence of LADA among diabetic individuals using the studies published at global levels.

METHODS

A comprehensive literature revival was performed to identify articles on the prevalence of LADA published till 2023. The prevalence estimates were calculated using DerSimonian and Laird random-effects models with a heterogeneity measure by Cochrane Q and I2 statistics. Publication bias was assessed by the Doi plot and Luis Furuya-Kanamori asymmetry index (LFKindex). P < 0.05 was considered statistically significant.

RESULTS

The overall pooled prevalence of LADA obtained from a total of 51,725 diabetic individuals was found to be 8.9% (95%CI 7.5-10.4, P < 0.001) with a prevalence range of 2.3% in to 18.9% in United Arab Emirates and Bahrain respectively. Subgroup analysis of LADA in the context of the IDF geographic regions showed a higher prevalence in North America (13.5%), 9.5% in Middle East and North Africa, 9.4% in Africa, 9.2% in South East Asia, 8.3% in Western Pacific and the lowest prevalence of 7.0% in Europe.

CONCLUSION

The Meta-analysis revealed a worldwide prevalence of LADA as 8.9%, with the highest prevalence in Bahrain and the lowest in United Arab Emirates. Further, the higher prevalence in some IDF regions and the inconsistent association between socioeconomic status and LADA recommend more research in the future.

Development and validation of a clinical score for identifying patients with high risk of latent autoimmune adult diabetes (LADA): The LADA primary care-protocol study

BACKGROUND

Latent autoimmune diabetes in adults (LADA) is a type of diabetes mellitus showing overlapping characteristics between type 1 Diabetes Mellitus and type 2 Diabetes Mellitus (T2DM), and autoimmunity against insulin-producing pancreatic cells. For its diagnosis, at least one type of anti-pancreatic islet antibody (GADAb is the most common) is required. Many authors recommend performing this measure in all newly diagnosed patients with DM, but it is not possible in Primary Health Care (PHC) due to its high cost. Currently, a relevant proportion of patients diagnosed as T2DM could be LADA. Confusing LADA with T2DM has clinical and safety implications, given its different therapeutic approach. The main objective of the study is to develop and validate a clinical score for identifying adult patients with DM at high risk of LADA in PHC.

METHODS

This is an observational, descriptive, cross-sectional study carried out in Primary Care Health Centers with a centralized laboratory. All people over 30 years of age diagnosed with diabetes within a minimum of 6 months and a maximum of 4 years before the start of the study will be recruited. Individuals will be recruited by consecutive sampling. The study variables will be obtained through clinical interviews, physical examinations, and electronic medical records. The following variables will be recorded: those related to Diabetes Mellitus, sociodemographic, anthropometric, lifestyle habits, laboratory parameters, presence of comorbidities, additional treatments, personal or family autoimmune disorders, self-perceived health status, Fourlanos criteria, and LADA diagnosis (as main variable) according to current criteria.

DISCUSSION

The study will provide an effective method for identifying patients at increased risk of LADA and, therefore, candidates for antibody testing. However, a slight participation bias is to be expected. Differences between participants and non-participants will be studied to quantify this potential bias.

Prevalence and factors associated with latent autoimmune diabetes in adults (LADA): a cross-sectional study

BACKGROUND

The Latent Autoimmune Diabetes in Adults (LADA) is a slowly progressive Type 1 diabetes subgroup with onset during middle age. Studies report that about 10% of adults initially diagnosed with clinical Type 2 diabetes (T2D) have LADA. Inappropriate diagnosis and mismanagement of the LADA can increase the risk of diabetic complications, which affect the quality of life and is the cause of increased mortality. In low-income countries setting, data regarding the magnitude of LADA is limited. We carried out this study to estimate the burden of misdiagnosed LADA among T2D patients in selected health facilities in Dar es Salaam and to bring awareness to the use of Glutamic Acid Decarboxylase (GAD) autoantibody in screening for LADA.

METHODOLOGY

We enrolled 186 phenotypically T2D patients in this cross-sectional study, through a standardized data collection tool we obtained participants' demographic and clinical information. For testing GAD levels, we used a double-antibody Enzyme-Linked Immunosorbent Assay (ELISA). The Fisher's Exact and student t-tests were used to test the significance of the statistical associations of the glycaemic control and diabetes complications between T2D and LADA.

RESULTS

Out of 186 patients, 156 gave conclusive GAD Ab ELISA reading with LADA accounting for 5.1% (95% CI: 2.5 - 10.0). The mean age of subjects was 54.3 years (Range: 33-85 years). The parameters such as mean age, family history of diabetes mellitus status, Fasting Blood Glucose, clinical characteristics, and complications did not show significant statistical differences between patients with LADA and Type 2 diabetes. However, all LADA- Human Immunodeficiency Virus (HIV) comorbid patients had retinopathy, which was statistically insignificant in 20 (87%) T2D-HIV comorbid patients (p = 0.669). Neither neuropathy, nephropathy, nor Diabetic Mellitus (D.M.) foot syndrome was observed among LADA-HIV comorbid patients. Nevertheless, 22 (95.7%), 3 (13%), and 2 (8.7%) of T2D-HIV comorbidity had neuropathy, nephropathy, or D.M. foot syndrome, respectively.

CONCLUSIONS

The study established a LADA prevalence of 5.1% among T2D patients and has shown the role of GAD autoantibody in the screening for LADA. The study calls for a well- designed larger longitudinal study to generate strong evidence on the association of risk factors and complications associated with the LADA. This will develop robust evidence on the association of risk factors and complications associated with the LADA and T2D.

Islet autoantibody positivity in an adult population with recently diagnosed diabetes in Uganda

Aims

This study aimed to investigate the frequency of islet autoantibody positivity in adult patients with recently diagnosed diabetes in Uganda and its associated characteristics.

Methods

Autoantibodies to glutamic acid decarboxylase-65 (GADA), zinc transporter 8 (ZnT8-A), and tyrosine phosphatase (IA-2A) were measured in 534 adult patients with recently diagnosed diabetes. Islet autoantibody positivity was defined based on diagnostic thresholds derived from a local adult population without diabetes. The socio-demographic, clinical, and metabolic characteristics of islet autoantibody-positive and negative participants were then compared. The differences in these characteristics were analysed using the x² test for categorical data and the Kruskal Wallis test for continuous data. Multivariate analysis was performed to identify predictors of islet autoantibody positivity.

Results

Thirty four (6.4%) participants were positive for ≥1 islet autoantibody. GADA, IA-2A and ZnT8-A positivity was detected in 17 (3.2%), 10 (1.9%), and 7 (1.3%) participants, respectively. Compared with those negative for islet autoantibodies, participants positive for islet autoantibodies were more likely to live in a rural area (n = 18, 52.9% Vs n = 127, 25.5%, p = 0.005), to be initiated on insulin therapy (n = 19, 55.9% Vs n = 134, 26.8%, p<0.001), to have a lower median waist circumference (90 [80–99] cm Vs 96 [87–104.8], p = 0.04), waist circumference: height ratio (0.55 [0.50–0.63] vs 0.59 [0.53–0.65], p = 0.03), and fasting C-peptide concentration (0.9 [0.6–1.8] Vs 1.4 [0.8–2.1] ng/ml, p = 0.01). On multivariate analysis, living in a rural area (odds ratio or OR 3.62, 95%CI 1.68–7.80, p = 0.001) and being initiated on insulin therapy (OR 3.61, 95% CI 1.67–7.83, p = 0.001) were associated with islet autoantibody positivity.

Conclusion

The prevalence of islet autoantibody positivity was relatively low, suggesting that pancreatic autoimmunity is a rare cause of new-onset diabetes in this adult Ugandan population. Living in a rural area and being initiated on insulin therapy were independently associated with islet autoantibody positivity in this study population.

Prevalence of Latent Autoimmune Diabetes in Adult Based on the Presence of GAD 65 Antibodies in North-Eastern Uttar Pradesh, India

Objective The objective of this paper was (1) to study the prevalence of latent autoimmune diabetes in adult (LADA) in the region of north-eastern Uttar Pradesh, India, based on the positivity for glutamic acid decarboxylase 65 (GAD65) antibodies and (2) to compare the glycemic profile between GAD65-positive and GAD65-negative subjects.

Materials and Methods The subjects were of more than 30 years of age, with either recently diagnosed pre-diabetes/diabetes presenting with the hemoglobin A1c (HbA1c) level of ≥5.7% or already diagnosed cases of type 2 diabetes mellitus (T2DM) who had no requirement of insulin therapy for at least 6 months from the time of their diagnosis. All the patients were natives of north-eastern Uttar Pradesh. The GAD65 test was done by the enzyme-linked immunosorbent assay. Further, the glycemic status of GAD-positive and GAD-negative subjects were compared on the basis of fasting blood sugar (FBS), fasting insulin (FI), and homeostatic model assessment for insulin resistance (HOMA-IR).

Statistical Analysis The “unpaired t-test” was used to compare and assess the significance of differences between the glycemic profile of GAD65-positive and GAD65-negative subjects using the GraphPad Prism Scientific Software, San Diego, CA, United States. The p-value of <0.05 was considered to be significant.

Results A total of 77 patients were included in the study, with the age group ranging from 30 to 75 years (47.81 ± 12.9 years) with the male–female ratio of 1:2.6. The prevalence of LADA was found to be 51.95%. On comparing GAD65-positive and GAD65-negative groups, a higher value of HbA1c levels and FBS were found in the former, whereas FI and HOMA-IR were found to be higher in the latter. On testing for significance of difference, only FI and HbA1c values were significant (p-value <0.0001).

Conclusion LADA can no longer be considered a rare type of diabetes mellitus, with the present study showing a high prevalence of LADA in this north eastern region of Uttar Pradesh. Identification of adult-onset diabetics accurately as LADA or true T2DM is very crucial for the appropriate treatment, as LADA patients require insulin inevitably and much earlier than true T2DM patients, who can be managed mostly on oral hypoglycemic agents with seldom requirement of insulin.

Latent Autoimmune Diabetes in Adults and Metabolic Syndrome-A Mini Review

Latent autoimmune diabetes in adults (LADA) is a heterogeneous subtype of diabetes characterized by islet cell destruction mediated by islet autoimmunity and insulin resistance. Metabolic syndrome (MetS) is a state in which many risk factors for metabolic and cardiovascular diseases accumulate in an individual. Based on clinical data, this review covers the prevalence of MetS in LADA, focusing on the risk associated with and the role of insulin resistance in the development of LADA from the perspective of inflammatory factors, environmental factors, and the gut microbiota, aiming to improve our understanding of this condition.

Low rate of latent autoimmune diabetes in adults (LADA) in patients followed for type 2 diabetes: A single center's experience in Turkey

Objective

In this study, we aimed to determine the frequency of and the clinical and metabolic features of patients with latent autoimmune diabetes in adults (LADA) at a single center in Turkey.

Methods

Patients over 30 years of age diagnosed with type 2 diabetes who did not require insulin for a minimum of 6 months following diagnosis were included. Data from 324 patients (163 women; 161 men), with a mean age of 54.97 ± 7.53 years, were analyzed in the study. Levels of antibodies to glutamate decarboxylase (anti-GAD) were measured in all patients, and LADA was diagnosed in patients testing positive for anti-GAD antibodies.

Results

Anti-GAD positivity was identified in 5 patients (1.5%). Family history of diabetes, body mass index (BMI), age, sex distribution, insulin resistance, serum triglycerides, high-density lipoprotein, and low-density lipoprotein were similar in the LADA and type 2 diabetes patients. Median HbA1c was significantly higher (10.8% vs. 7.38%, p = 0.002) and fasting C-peptide was lower (0.75 ng/mL vs. 2.82 ng/mL, p = 0.009) in patients with LADA compared to in those with type 2 diabetes. Among the 5 patients with LADA, 4 were positive for antithyroid peroxidase antibodies. The median disease duration was relatively shorter among patients with LADA (4 years vs. 7 years, p = 0.105).

Conclusion

We observed a LADA frequency of 1.5% among Turkish patients followed for type 2 diabetes. The presence of obesity and metabolic syndrome did not exclude LADA, and patients with LADA had worse glycemic control than patients with type 2 diabetes did.

Type 1 diabetes mellitus: much progress, many opportunities

As part of the centennial celebration of insulin's discovery, this review summarizes the current understanding of the genetics, pathogenesis, treatment, and outcomes in type 1 diabetes (T1D). T1D results from an autoimmune response that leads to destruction of the β cells in the pancreatic islet and requires lifelong insulin therapy. While much has been learned about T1D, it is now clear that there is considerable heterogeneity in T1D with regard to genetics, pathology, response to immune-based therapies, clinical course, and susceptibility to diabetes-related complications. This Review highlights knowledge gaps and opportunities to improve the understanding of T1D pathogenesis and outlines emerging therapies to treat or prevent T1D and reduce the burden of T1D.

Latent Autoimmune Diabetes in Adults (LADA) and its Metabolic Characteristics among Yemeni Type 2 Diabetes Mellitus Patients

PURPOSE

Although there is ample data about the prevalence of diabetes in the Middle East, little is known about the prevalence and features of autoimmune diabetes in this region. The aim of this study was to investigate the prevalence and metabolic characteristics of latent autoimmune diabetes in adults (LADA) amongst Yemeni Type 2 DM patients.

PATIENTS AND METHODS

In this cross-section study, 270 Type 2 DM patients aged 30-70 years were recruited from the National Diabetes Center, Al-Thowra Hospital, Sana'a city, during the period November 2015 to August 2016. All Type 2 DM patients were diagnosed within 5 years and who did not require insulin for a minimum of 6 months following diagnosis. Levels of glutamic acid decarboxylase autoantibodies (GADA) were measured in all patients, and LADA was diagnosed in patients testing positive for anti-GAD antibodies. Further, biochemical analysis was carried out including fasting blood glucose (FBG), glycated haemoglobin (HbA1c), insulin, and lipid profile. Insulin resistance (HOMA-IR) and β-cell function (HOMA-β) were calculated.

RESULTS

The prevalence of LADA, as defined by GADA-positive, amongst patient with Type 2 DM was 4.4%; with no significant difference in the prevalence between male (5.8%) and female (3.4%). LADA patients were younger than GADA-negative Type 2 DM. Body mass index, waist circumference, insulin and HOMA-β were significantly lower in LADA patients, whereas triglyceride, cholesterol, HDL-c and HOMA-IR were non-significantly lower with respect to Type 2 DM. In contrast, FBG and HbA1c were significantly higher in LADA patients. Moreover, the prevalence of metabolic syndrome was significantly lower in LADA as compared with Type 2 DM. Only 2 out of the 12 GADA-positive (16.7%) were on insulin treatment at the time of the study.

CONCLUSION

The prevalence of LADA in Yemeni Type 2 DM is lower than many of those reported in the literature, with no gender preference. Metabolic syndrome was significantly lower in LADA patients. Patients with LADA share insulin resistance with Type 2 DM but display a more severe defect in β-cell function, thus highlighting the importance of an early diagnosis of LADA, to correctly treat LADA patients, allowing safe and effective therapies.

Adult-onset autoimmune diabetes: comparative analysis of classical and latent presentation

INTRODUCTION

Adult-onset autoimmune diabetes (AID) has two different phenotypes: classic type 1 diabetes mellitus (T1DM), with insulin requirement just after diagnosis, and latent autoimmune diabetes in adults (LADA). The purpose of this study is to characterize patients with AID followed on a tertiary centre, comparing classic T1DM and LADA.

METHODS

We collected data from patients with diabetes and positive islet autoantibodies, aged 30 years old and over at diagnosis. Patients who started insulin in the first 6 months were classified as T1DM and patients with no insulin requirements in the first 6 months were classified as LADA. Data regarding clinical presentation, autoantibodies, A1C and C-peptide at diagnosis, pharmacologic treatment and complications were analysed.

RESULTS

We included 92 patients, 46 with classic T1DM and 46 with LADA. The percentage of females was 50% in T1DM group and 52.1% in LADA group. The median age at diagnosis was 38 years (IQR-15) for T1DM and 42 years (IQR-15) for LADA (p = 0.057). The median time between diagnosis of diabetes and diagnosis of autoimmune aetiology was 0 months in T1DM group and 60 months in LADA group (p < 0.001). The mean BMI at diagnosis was 24.1 kg/m² in T1DM group and 26.1 kg/m² in LADA group (p = 0.042). In T1DM group, 67.4% of the patients had more than one positive autoantibody, comparing to 41.3% of LADA patients (p = 0.012). There was no statistical difference in what concerns to title of GAD autoantibodies, A1C and C-peptide at diagnosis of autoimmune aetiology. The presence of symptoms at diagnosis was associated with T1DM group (p < 0.001). The median daily insulin dose was 40 IU for T1DM (0.58 IU/kg) and 33.5 IU for LADA (0.57 IU/kg), with no statistical difference. LADA patients were more often under non-insulin antidiabetic drugs (p = 0.001). At 10 years follow up, 21.1% of T1DM patients and 63.3% of LADA patients had microvascular complications (p = 0.004). Diabetic nephropathy was present in 23.5% of T1DM patients and 53.3% of LADA patients (p = 0.047). At the last evaluation, 55.6% of T1DM and 82.6% of LADA patients had metabolic syndrome and this difference was independent of diabetes duration.

CONCLUSION

Patients with classic T1DM presented more often with symptoms, lower BMI and higher number of autoantibodies, which may be related to a more aggressive autoimmune process. Patients with LADA developed more frequently microvascular complications for the same disease duration, namely diabetic nephropathy, and had more often metabolic syndrome.

Prevalence of positive islet autoantibody in type 2 diabetes patients: a cross-sectional study in a Chinese community

BACKGROUND

Islet autoantibodies occur in type 2 diabetes. Our study aimed to investigate the prevalence of positive islet autoimmunity in community patients with type 2 diabetes.

METHODS

A total of 495 community patients with type 2 diabetes were recruited using the method of cluster sampling in this cross-sectional study. Three islet autoantibodies including glutamic acid decarboxylase antibody (GADA), insulin autoantibody (IAA) and islet cell antibody (ICA) were measured, and clinical characteristics involved in those individuals were evaluated.

RESULTS

The positive rate of islet autoantibodies was 28.5% in total, while combinations of different autoantibodies were rarely seen. Compared with GADA-negative group, positive counterparts significantly tended to have lower levels of body mass index (BMI), waist-hip ratio (WHR), and urinary microalbumin (mALB) (P < 0.05). Adjusted for confounding factors, WHR, triglycerides (TG), and mALB seemed to be negative independent predictors of GADA (OR < 1, P < 0.05). Patients with positive IAA tended to receive insulin treatment (P < 0.0001). Besides, fasting blood glucose (FBG), serum levels of high-density lipoprotein cholesterol (HDL-CH), aspartate transaminase (AST), and γ-glutamyltransferase (GGT) were more likely to be higher in IAA positive subgroup in comparison with the negative counterparts. While after AST was adjusted by unconditional logistic regression analysis, history of insulin treatment, FBG, HDL-CH, and GGT were confirmed as positive predictors of IAA. Furthermore, in patients who were IAA positive, those treated with exogenous insulin tended to have longer duration of diabetes than non-insulin treatment counterparts (P < 0.0001). With regard to ICA, however, there were no significant differences between the two subgroups, except that serum level of AST/ALT seemed to be slightly different (P = 0.064).

CONCLUSION

These data suggested that type 2 diabetic community patients with positive GADA tended to be lean and were able to maintain normal lipid metabolism, while patients with positivity of IAA were frequently accompanied with insulin treatment and more closely associated with diabetic liver damage.

Investigating optimal β-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 β-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

β-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 β-cell function over a 21-month period. Taken together, these findings could be useful for clinicians' choices of treatment in people with LADA.

The Influence of Type 2 Diabetes-Associated Factors on Type 1 Diabetes

Current efforts to prevent progression from islet autoimmunity to type 1 diabetes largely focus on immunomodulatory approaches. However, emerging data suggest that the development of diabetes in islet autoantibody-positive individuals may also involve factors such as obesity and genetic variants associated with type 2 diabetes, and the influence of these factors increases with age at diagnosis. Although these factors have been linked with metabolic outcomes, particularly through their impact on β-cell function and insulin sensitivity, growing evidence suggests that they might also interact with the immune system to amplify the autoimmune response. The presence of factors shared by both forms of diabetes contributes to disease heterogeneity and thus has important implications. Characteristics that are typically considered to be nonimmune should be incorporated into predictive algorithms that seek to identify at-risk individuals and into the designs of trials for disease prevention. The heterogeneity of diabetes also poses a challenge in diagnostic classification. Finally, after clinically diagnosing type 1 diabetes, addressing nonimmune elements may help to prevent further deterioration of β-cell function and thus improve clinical outcomes. This Perspectives in Care article highlights the role of type 2 diabetes-associated genetic factors (e.g., gene variants at transcription factor 7-like 2 [TCF7L2]) and obesity (via insulin resistance, inflammation, β-cell stress, or all three) in the pathogenesis of type 1 diabetes and their impacts on age at diagnosis. Recognizing that type 1 diabetes might result from the sum of effects from islet autoimmunity and type 2 diabetes-associated factors, their interactions, or both affects disease prediction, prevention, diagnosis, and treatment.

Treatment of Latent Autoimmune Diabetes in Adults: What is Best?

Latent Autoimmune Diabetes in Adults (LADA), although formally classified as Type 1 Diabetes (T1D), very often (at least in Western countries) appear clinically with Type 2 Diabetes (T2D)-like features as overweight and insulin resistance. LADA patients do not need exogenous insulin at the time they are diagnosed with diabetes, but a large percentage will within a few years develop need for such treatment. The decline in beta cell function progresses much faster in LADA than in T2D, presumably because of the ongoing autoimmune assault in LADA, and therefore necessitates insulin therapy much earlier in LADA than in T2D. Despite high prevalence of LADA (about 10% of the total diabetic population in many countries), the treatment of LADA patients is far less elucidated than is the case for T1D and T2D. Finding a treatment strategy for LADA from the time of diagnosis, that can reduce the decline of beta cell function, ensure adequate metabolic control and thereby reduce the risk of diabetic complications is thus an important clinical challenge. Conclusions from the randomized treatment studies so far do not indicate an optimal treatment strategy in LADA. This review aims to give an overview of current practices for the medical treatment of LADA as well as an update on results from recent studies on the treatment of the disease.

Identification of a distinct phenotype of elderly latent autoimmune diabetes in adults: LADA China Study 8

BACKGROUND

Latent autoimmune diabetes in adults (LADA) exhibits significant clinical heterogeneity, but the underlying causes remain unclear. The aim of this study was to investigate whether age of onset of LADA contributes to the observed clinical heterogeneity by comparing the clinical, metabolic, and immunogenetic characteristics between elderly and young LADA patients.

METHODS

The cross-sectional study included a total of 579 patients with LADA which was further divided into elderly LADA (E-LADA) group (n = 135, age of onset ≥60 years) and young LADA (Y-LADA) group (n = 444, age of onset <60 years). Age-matched subjects with type 2 diabetes were served as control (E-T2D group, n = 622). Clinical characteristics, serum autoantibodies, and HLA-DQ haplotypes were compared among these groups.

RESULTS

Compared with patients with Y-LADA, patients with E-LADA have better residual beta-cell function and higher level of insulin resistance (both P < .01), more metabolic syndrome characteristics, similar proportion of islet autoantibody positivity, and strikingly different HLA-DQ genetic background. In comparison with E-T2D patients, E-LADA patients tend to have similar metabolic syndrome prevalence, comparable C-peptide levels, and insulin resistance levels and share similar HLA-DQ genetic characteristics.

CONCLUSIONS

Elderly LADA differs phenotypically and genetically from Y-LADA but has a clinical and genetic profile more similar to that of E-T2D. These distinct phenotypes could potentially help physicians better manage patients with E-LADA.

A form of Autoimmune Diabetes in Adults Named LADA - An Update on Essential Features and Controversies

Latent Autoimmune Diabetes in the Adult, LADA has been investigated less than "classical" type 1 and type 2 diabetes and the criteria for and the relevance of a LADA diagnosis has been challenged. Despite the absence of a genetic background that is exclusive to LADA, this form of diabetes displays phenotypic characteristics that distinguish it from other forms of diabetes. LADA is heterogeneous in terms of the impact of autoimmunity and lifestyle factors, something that poses problems as to therapy and follow-up perhaps particularly in those with marginal positivity. Yet, there appears to be clear clinical utility in classifying individuals as LADA.

LADA: A Type of Diabetes in its Own Right?

Latent Autoimmune Diabetes in the Adult, LADA has been investigated less than "classical" type 1 and type 2 diabetes and the criteria for and the relevance of a LADA diagnosis have been challenged. Despite the absence of a genetic background that is exclusive for LADA this form of diabetes displays phenotypic characteristics that distinguish it from other forms of diabetes. LADA is heterogeneous in terms of the impact of autoimmunity and lifestyle factors, something that poses problems to therapy and follow-up, perhaps particularly in those with marginal positivity. Yet, there appears to be clear clinical utility in classifying individuals as LADA.

Distinct neutrophil counts and functions in newly diagnosed type 1 diabetes, latent autoimmune diabetes in adults, and type 2 diabetes

BACKGROUND

Recent discoveries from animal models demonstrated that neutrophils can induce type 1 diabetes (T1D) through infiltrating into the islets. However, the evidence of their actions in T1D patients is relatively rare, and the change trend of neutrophil numbers and functions in different subtypes of diabetes has not been investigated.

METHODS

Patients with newly diagnosed T1D (n = 189), latent autoimmune diabetes in adults (LADA) (n = 86), T2D (n = 235), and healthy controls (n = 709) were enrolled. Circulating neutrophil counts were measured, and their correlations with clinical parameters were analysed. Neutrophils were isolated by density gradient centrifugation and magnetic bead cell sorting method. Neutrophil migration rate and chemokine levels in the blood were explored by trans-well and ELISA, respectively. Neutrophil phagocytosis rate, adhesion molecules and chemokine receptors expression were investigated by flow cytometry.

RESULTS

Compared with controls, neutrophil counts decreased in T1D patients but increased in T2D patients, with no change in LADA patients. The numbers showed a gradual increase trend from T1D, LADA to T2D. In autoimmune diabetes, neutrophil counts were associated with the number and titre of positive autoantibodies against β-cell antigens. No difference was found in neutrophil phagocytosis rate, but neutrophil migration in T1D patients was impaired and associated with CD62L expression, which was related closely to the titre of autoantibody.

CONCLUSIONS

Neutrophil numbers and migration abilities displayed distinct levels in different types of diabetes. In T1D, CD62L seems to play an important role in the migration of neutrophils and β-cell autoimmunity.

Autoantibodies as Diagnostic Tools

Autoimmune diseases are very diverse and include many common diseases of unknown etiology.Diagnosis can be challenging but can be facilitated by the identification of characteristic autoantibodies (AuAbs), which are present in varying frequencies. Identification of such AuAbs requires a range of different techniques, depending on the autoantigens in question. Each individual AuAb assay is characterized by analytical sensitivity and specificity, which in turn determines clinical sensitivity and specificity in relation to diseases. Clinical sensitivities and specificities vary much, but many AuAb analyses can be of significant help in establishing correct diagnoses. It remains unsettled whether AuAbs are generally pathogenic, but it is generally agreed that autoimmune diseases are caused by a combination of genetic and environmental factors, and that early and correct diagnosis facilitates treatment.

Glutamic Acid Decarboxylase Autoantibody-negative Slowly Progressive Type 1 Diabetes Mellitus: A Case Report and Literature Review

A 59-year-old non-obese Japanese woman developed diabetes mellitus with a negative glutamic acid decarboxylase autoantibody (GADA) test result. Her hyperglycemia was initially well controlled by oral hypoglycemic agents; however, despite continued treatment the hyperglycemia gradually worsened. As she had endogenous insulin deficiency and tested positive for insulin autoantibody (IAA), insulin therapy was initiated. Few studies have investigated GADA-negative patients with slowly progressive type 1 diabetes mellitus (SPT1D). Our IAA-positive SPT1D patient progressed from the clinical onset of diabetes mellitus to starting insulin therapy relatively quickly (1.5 years), similarly to other previously reported non-obese patients with GADA-positive SPT1D.

Metabolic Characteristics of Recently Diagnosed Adult-Onset Autoimmune Diabetes Mellitus

CONTEXT AND OBJECTIVE

Among patients diagnosed with type 2 diabetes, autoimmune diabetes often remains undetected. Metabolic features of these patients are insufficiently characterized at present.

DESIGN, SETTING, AND PATIENTS

This study compared age- and sex-matched adult (aged 41 to 62 years) humans with recent-onset diabetes: patients positive for antibodies against glutamic acid decarboxylase (GAD) and/or cytoplasmic islet-cell antigen with an insulin-free period of >6 months [antibody positive/insulin negative (ab+/ins-); previously termed latent autoimmune diabetes of adults], type 1 diabetes [antibody positive/insulin positive (ab+/ins+)], and type 2 diabetes [antibody negative/insulin negative (ab-/ins-)], as well as glucose-tolerant humans (controls) of the German Diabetes Study (n = 41/group). β-Cell function was assessed from glucagon tests and intravenous glucose tolerance tests (IVGTTs), and insulin sensitivity was determined from hyperinsulinemic-euglycemic clamps.

RESULTS

Of the ab+/ins- patients, 33 (81%) were initially diagnosed as having type 2 diabetes. In ab+/ins-, body mass index (BMI) was higher than in ab+/ins+ (27.8 ± 5.3 kg/m2 vs 25.0 ± 3.5 kg/m2, P < 0.05), lower than in ab-/ins- (31.9 ± 5.8 kg/m2, P < 0.05), and similar to controls (29.4 ± 6.6 kg/m2). In ab+/ins-, GAD antibody titers correlated negatively with BMI (r = -0.40, P < 0.05) and with C-peptide secretion in glucagon stimulation tests (r = -0.33, P < 0.05). β-Cell function from IVGTT was 228% higher in ab+/ins- than in ab+/ins+ but 35% lower than in ab-/ins- and 61% lower than in controls (all P < 0.05). Insulin sensitivity in ab+/ins- was comparable to ab+/ins+ and controls but 41% higher than in ab-/ins- (P < 0.05) after adjustment for BMI and fasting blood glucose or hemoglobin A1c.

CONCLUSION

Even shortly after diagnosis, ab+/ins- patients feature partly preserved β-cell function and chronic hyperglycemia, which possibly contributes to the observed impairment of whole-body insulin sensitivity.

Fluctuations in the incidence of type 1 diabetes in the United States from 2001 to 2015: a longitudinal study

BACKGROUND

While the United States has the largest number of children with type 1 diabetes mellitus, less is known regarding adult-onset disease. The present study utilizes nationwide data to compare the incidence of type 1 diabetes in youth (0-19 years) to that of adults (20-64 years).

METHODS

In this longitudinal study, the Clinformatics® Data Mart Database was used, which contains information from 61 million commercially insured Americans (years 2001-2015). Incidence rates and exact Poisson 95% confidence intervals were calculated by age group, sex, census division, and year of diagnosis. Changes in rates over time were assessed by negative binomial regression.

RESULTS

Overall, there were 32,476 individuals who developed type 1 diabetes in the cohort. The incidence rate was greatest in youth aged 10-14 years (45.5 cases/100,000 person-years); however, because adulthood spans over a longer period than childhood, there was a greater number of new cases in adults than in youth (n = 19,174 adults; n = 13,302 youth). Predominance in males was evident by age 10 and persisted throughout adulthood. The male to female incidence rate ratio was 1.32 (95% CI 1.30-1.35). The incidence rate of type 1 diabetes in youth increased by 1.9% annually from 2001 to 2015 (95% CI 1.1-2.7%; P < 0.001), but there was variation across regions. The greatest increases were in the East South Central (3.8%/year; 95% CI 2.0-5.6%; P < 0.001) and Mountain divisions (3.1%/year; 95% CI 1.6-4.6%; P < 0.001). There were also increases in the East North Central (2.7%/year; P = 0.010), South Atlantic (2.4%/year; P < 0.001), and West North Central divisions (2.4%/year; P < 0.001). In adults, however, the incidence decreased from 2001 to 2015 (-1.3%/year; 95% CI -2.3% to -0.4%; P = 0.007). Greater percentages of cases were diagnosed in January, July, and August for both youth and adults. The number of new cases of type 1 diabetes (ages 0-64 years) in the United States is estimated at 64,000 annually (27,000 cases in youth and 37,000 cases in adults).

CONCLUSIONS

There are more new cases of type 1 diabetes occurring annually in the United States than previously recognized. The increase in incidence rates in youth, but not adults, suggests that the precipitating factors of youth-onset disease may differ from those of adult-onset disease.