LADA prevalence estimation and insulin dependency during follow-up

New Perspectives in Studying Type 1 Diabetes Susceptibility Biomarkers

Type 1 diabetes (T1D) is generally viewed as an etiologic subtype of diabetes caused by the autoimmune destruction of the insulin-secreting β-cells. It has been known that autoreactive T cells unfortunately destroy healthy β-cells. However, there has been a notion of etiologic heterogeneity around the world implicating a varying incidence of a non-autoimmune subgroup of T1D related to insulin deficiency associated with decreased β cell mass, in which the β-cell is the key contributor to the disease. Beta cell dysfunction, reduced mass, and apoptosis may lead to insufficient insulin secretion and ultimately to the development of T1D. Interestingly, Korean as well as other ethnic genetic results have also suggested that genes related with insulin deficiency, let alone those of immune regulation, were associated with the risk of T1D in the young. Genes related with insulin secretion may influence the phenotype of diabetes differentially and different genes may be working on different steps of T1D development. Although we admit the consensus that islet autoimmunity is an essential component in the pathogenesis of T1D, however, dysfunction might occur not only in the immune system but also in the β-cells, the defect of which may induce further dysfunction of the immune system. These arguments stem from the fact that the β-cell might be the trigger of an autoimmune response. This emergent view has many parallels with the fact that by their nature and function, β-cells are prone to biosynthetic stress with limited measures for self-defense. Beta cell stress may induce an immune attack that has considerable negative effects on the production of a vital hormone, insulin. If then, both β-cell stress and islet autoimmunity can be harnessed as targets for intervention strategies. This also may explain why immunotherapy at best delays the progression of T1D and suggests the use of alternative therapies to expand β-cells, in combination with immune intervention strategies, to reverse the disease. Future research should extend to further investigate β-cell biology, in addition to studies of immunologic areas, to find appropriate biomarkers of T1D susceptibility. This will help to decipher β-cell characteristics and the factors regulating their function to develop novel therapeutic approaches.

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.

C-peptide determination in the diagnosis of type of diabetes and its management: A clinical perspective

Impaired beta-cell function is a recognized cornerstone of diabetes pathophysiology. Estimates of insulin secretory capacity are useful to inform clinical practice, helping to classify types of diabetes, complication risk stratification and to guide treatment decisions. Because C-peptide secretion mirrors beta-cell function, it has emerged as a valuable clinical biomarker, mainly in autoimmune diabetes and especially in adult-onset diabetes. Nonetheless, the lack of robust evidence about the clinical utility of C-peptide measurement in type 2 diabetes, where insulin resistance is a major confounder, limits its use in such cases. Furthermore, problems remain in the standardization of the assay for C-peptide, raising concerns about comparability of measurements between different laboratories. To approach the heterogeneity and complexity of diabetes, reliable, simple and inexpensive clinical markers are required that can inform clinicians about probable pathophysiology and disease progression, and so enable personalization of management and therapy. This review summarizes the current evidence base about the potential value of C-peptide in the management of the two most prevalent forms of diabetes (type 2 diabetes and autoimmune diabetes) to address how its measurement may assist daily clinical practice and to highlight current limitations and areas of uncertainties to be covered by future research.

Latent autoimmune diabetes in adults in China

Latent autoimmune diabetes in adults (LADA) is a type of diabetes caused by slow progression of autoimmune damage to pancreatic beta cells. According to the etiological classification, LADA should belong to the autoimmune subtype of type 1 diabetes (T1D). Previous studies have found general immune genetic effects associated with LADA, but there are also some racial differences. Multicenter studies have been conducted in different countries worldwide, but it is still unclear how the Chinese and Caucasian populations differ. The epidemiology and phenotypic characteristics of LADA may vary between Caucasian and Chinese diabetic patients as lifestyle, food habits, and body mass index differ between these two populations. The prevalence of LADA in China has reached a high level compared to other countries. The prevalence of LADA in China has reached a high level compared to other countries, and the number of patients with LADA ranks first in the world. Previous studies have found general immune genetic effects associated with LADA, but some racial differences also exist. The prevalence of LADA among newly diagnosed type 2 diabetes patients over the age of 30 years in China is 5.9%, and LADA patients account for 65% of the newly diagnosed T1D patients in the country. As a country with a large population, China has many people with LADA. A summary and analysis of these studies will enhance further understanding of LADA in China. In addition, comparing the similarities and differences between the Chinese and the Caucasian population from the perspectives of epidemiology, clinical, immunology and genetics will help to improve the understanding of LADA, and then promote LADA studies in individual populations.

Latent autoimmune diabetes in youth shows greater autoimmunity than latent autoimmune diabetes in adults: Evidence from a nationwide, multicenter, cross-sectional study

AIM

To investigate the prevalence and clinical features of latent autoimmune diabetes in youth (LADY) diagnosed between 15 and 29 years old as a component of an age-related autoimmune diabetes spectrum.

RESEARCH DESIGN AND METHODS

This nationwide, multicenter, cross-sectional study continuously included 19,100 newly diagnosed diabetes patients over 15 years old across China. LADY patients were screened from 1803 subjects aged between 15 and 29 years old, with the type 2 diabetes (T2D) phenotype and positive autoantibodies against glutamic acid decarboxylase (GADA), insulinoma-associated-2 (IA-2A) or zinc transporter-8 (ZnT8A). The clinical features of LADY, including metabolic status, β-cell function and insulin resistance, were investigated and compared with those of latent autoimmune diabetes in adults (LADA) identified from 17,297 other subjects over 30 years old. The age-related characteristics of the latent autoimmune diabetes spectrum were explored.

RESULTS

A total of 135 subjects were diagnosed as LADY, accounting for 9.0% of the T2D phenotypic youth. Compared with autoantibody-negative T2D patients, LADY patients had fewer metabolic syndrome, less insulin resistance and poorer β-cell function, which were closely related to their autoantibody status (all p < 0.05). After stratifying LADA according to age, the GADA titer decreased across the LADY, "Y-LADA" (young LADA, onset age < 60 years old) and "E-LADA" (elderly LADA, onset age ≥ 60 years old) groups, while the prevalence of metabolic syndrome and level of β-cell function increased (all p < 0.05).

CONCLUSIONS

A high prevalence of LADY exists in youth with T2D phenotype. Latent autoimmune diabetes forms a continuous age-related spectrum from LADY to LADA, in which LADY shows greater autoimmunity.

Recent information on test utilization and intraindividual change in anti-glutamic acid decarboxylase antibody in Korea: a retrospective study

INTRODUCTION

This study aimed to evaluate the test utilization and intraindividual changes of anti-glutamic acid decarboxylase antibody (GADA), a biomarker for autoimmune diabetes in Korean adults.

RESEARCH DESIGN AND METHODS

We retrospectively investigated longitudinally measured GADA test results to assess test utilization and intraindividual changes through a laboratory information system.

RESULTS

During the 3-year study period, 11 668 GADA tests were performed in 11 184 Korean adults. The overall rate of GADA positivity at initial measurement was 7.8%. Among the 11 668 test results, 871 GADA test results from 401 Korean patients (228 men and 173 women) requested by 54 hospitals were analyzed for intraindividual changes. Among these 401 patients, 80 (20.0%) had positive (≥2.0 U/mL) and 35 (8.7%) had gray zone GADA (1.0-1.9 U/mL) level at initial measurement. The prevalence of GADA-positive patients based on initial measurement was significantly different by type of medical institution. Among 80 patients with initial positive results, 5 (6.3%) experienced qualitative GADA changes during follow-up. Among the 321 patients with initially negative or gray zone GADA, 9 (2.8%) changed to GADA positive at least once during follow-up.

CONCLUSIONS

Although most patients had stable GADA results, some exhibited qualitative changes during follow-up. This study can help to understand the variation in GADA positivity in the monitored patients.

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.

Autoantibodies against zinc transporter 8 further stratify the autoantibody-defined risk for type 1 diabetes in a general population of schoolchildren and have distinctive isoform binding patterns in different forms of autoimmune diabetes: results from the Karlsburg Type 1 Diabetes Risk Study

AIMS

To evaluate the diagnostic relevance of autoantibodies against zinc transporter 8 (ZnT8) in schoolchildren from the general population as well as in people with autoimmune diabetes.

METHODS

A total of 137 schoolchildren positive for at least one of the three major diabetes-associated autoantibodies, without diabetes heredity or preselection on HLA typing, from the Karlsburg Type 1 Diabetes Risk Study, as well as 102 people at type 1 diabetes onset, 88 people with latent autoimmune diabetes in adults and 119 people with type 2 diabetes, were analysed for different ZnT8 autoantibody variants.

RESULTS

Zinc transporter 8 autoantibody positivity was found in 18% of autoantibody-positive schoolchildren, with a noticeable association with other autoantibodies associated with type 1 diabetes and disease progression. Furthermore, ZnT8 autoantibody positivity was associated with diabetes progression in schoolchildren positive for autoantibodies against insulinoma-associated antigen-2 (IA-2) and, importantly, in seven IA-2 autoantibody-negative schoolchildren. Additionally, ZnT8 autoantibodies were found in 56% of people with type 1 diabetes, predominantly directed against all three ZnT8 variants and comparable to schoolchildren with multiple autoantibodies. In contrast, ZnT8 autoantibodies were detected in 10% of people with latent autoimmune diabetes in adults, none of them with reactivity to all three isoforms.

CONCLUSION

Zinc transporter 8 autoantibodies are useful markers for prediction of type 1 diabetes in a general population, further stratifying the risk of progression in autoantibody-positive children. ZnT8 autoantibodies are also important markers in adult-onset diabetes, with a completely different reaction pattern in type 1 diabetes in comparison to latent autoimmune diabetes in adults, and may therefore help to differentiate between the two forms.

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.

Latent Autoimmune Diabetes in Adults: A Review of Clinically Relevant Issues

Latent autoimmune diabetes in adults (LADA) is still a poorly characterized entity. However, its prevalence may be higher than that of classical type 1 diabetes. Patients with LADA are often misclassified as type 2 diabetes. The underlying autoimmune process against β-cell has important consequences for the prognosis, comorbidities, treatment choices and even patient-reported outcomes with this diabetes subtype. However, there is still an important gap of knowledge in many areas of clinical relevance. We are herein focusing on the state of knowledge of relevant clinical issues than may help in the diagnosis and management of subjects with LADA.

Past, present and future of latent autoimmune diabetes in adults

Latent autoimmune diabetes in adults (LADA) is the most common form of autoimmune diabetes diagnosed in adults. Similar to type 1 diabetes, the prevalence of LADA is impacted by ethnicity and geography. LADA is characterized by β cell loss due to autoimmunity and insulin resistance and has highly heterogeneous clinical features, autoimmunity, and genetics in a glutamic acid decarboxylase antibody (GADA) titre-dependent manner, suggesting LADA is part of a continuum spectrum between type 1 and type 2 diabetes. Although LADA is the most frequent form of autoimmune diabetes diagnosed in adults, clinical trials involving LADA are scarce. Here we review the recent advancements in LADA epidemiology, clinical features, pathogenesis, and interventions. We also highlight the environmental factors that are thought to play an important role in addition to genetics in the pathogenesis of LADA. In the future, high-throughput molecular profiles might shed light on the nature of LADA among the wide spectrum of diabetes and offer new opportunities to identify novel LADA-specific biomarkers.

The association between GAD65 antibody levels and incident Type 2 Diabetes Mellitus in an adult population: A meta-analysis

CONTEXT

Antibodies to the 65 kD isoform of glutamic acid decarboxylase (GAD65) have been associated with incident Type 2 Diabetes Mellitus, however results are inconsistent.

OBJECTIVE

To assess the association between GAD65 antibody positivity and incident Type 2 Diabetes Mellitus in a non-diabetic adult (≥18 years) population, in a systematic review and meta-analysis.

DATA SOURCES

A systematic literature search was conducted in Pubmed (MEDLINE) and Embase until January 14th, 2019.

STUDY SELECTION

Included studies were 1) prospective studies on the association between GAD65 antibodies and incident Type 2 Diabetes Mellitus; 2) in a non-diabetic adult (≥18 years) population. To strengthen the review, unpublished data from 1302 Hoorn Study participants were included.

DATA EXTRACTION

Data extraction and quality assessment were performed independently by two observers. Ten studies were rated for methodological quality and seven were pooled using a random-effects meta-analysis, of which 2 strong, 2 moderate and 3 of low methodological quality.

DATA SYNTHESIS

The pooled risk estimate of incident Type 2 Diabetes Mellitus for GAD65 antibody positivity, compared to GAD65 antibody negativity was 3.36 (95% CI: 1.9-5.9). This result was robust to sensitivity analyses. Heterogeneity between studies was significant with I² statistic of 79% (p < 0.0001). However, excluding one study showed a decrease of I² to 19% (p < 0.0001), explaining a large part of the heterogeneity.

CONCLUSION

GAD65 antibody positivity was associated with an increased risk of future Type 2 Diabetes Mellitus in adults.

Prevalence and identification of type 1 diabetes in Chinese adults with newly diagnosed diabetes

AIM

This study aimed to estimate the prevalence of latent autoimmune diabetes of adults (LADA) and classic type 1 diabetes mellitus (T1DM) in newly diagnosed adult diabetes in China.

METHOD

This cross-sectional study involved 17,349 newly diagnosed diabetes in adults aged ≥30 years from 46 hospitals within 31 months. Demographic characteristics, clinical features, and medical history were collected by trained researchers. T1DM as a whole was comprised of classic T1DM and LADA. Classic T1DM was identified based on the clinical phenotype of insulin-dependency, and LADA was differentiated from patients with initially an undefined diabetes type with standardized glutamic acid decarboxylase autoantibody testing at the core laboratory. The age and sex distributions from a large national survey of diabetes in China conducted in 2010 were used to standardize the prevalence of classic T1DM and LADA.

RESULTS

Among 17,349 adult patients, the prevalence of T1DM was 5.49% (95% CI: 4.90-6.08%) (5.14% [95% CI: 4.36-5.92%] in males and 6.16% [95% CI: 5.30-7.02%] in females), with 65% of these having LADA. The prevalence of classic T1DM decreased with increasing age (p<0.05), while that of LADA was stable (p>0.05). The prevalence of T1DM in overweight or obese patients was 3.42% (95% CI: 3.20-3.64%) and 2.42% (95% CI: 1.83-3.01%), respectively, and LADA accounted for 76.5% and 79.2% in these two groups.

CONCLUSION

We draw the conclusion that T1DM, especially LADA, was prevalent in newly diagnosed adult-onset diabetes in China, which highlights the importance of routine islet autoantibodies testing in clinical practice.

Latent Autoimmune Diabetes in Adults: A Review on Clinical Implications and Management

Latent autoimmune diabetes in adults (LADA) is a heterogeneous disease characterized by a less intensive autoimmune process and a broad clinical phenotype compared to classical type 1 diabetes mellitus (T1DM), sharing features with both type 2 diabetes mellitus (T2DM) and T1DM. Since patients affected by LADA are initially insulin independent and recognizable only by testing for islet-cell autoantibodies, it could be difficult to identify LADA in clinical setting and a high misdiagnosis rate still remains among patients with T2DM. Ideally, islet-cell autoantibodies screening should be performed in subjects with newly diagnosed T2DM, ensuring a closer monitoring of those resulted positive and avoiding treatment of hyperglycaemia which might increase the rate of β-cells loss. Thus, since the autoimmune process in LADA seems to be slower than in classical T1DM, there is a wider window for new therapeutic interventions that may slow down β-cell failure. This review summarizes the current understanding of LADA, by evaluating data from most recent studies, the actual gaps in diagnosis and management. Finally, we critically highlight and discuss novel findings and future perspectives on the therapeutic approach in LADA.

A Global Perspective of Latent Autoimmune Diabetes in Adults

Latent autoimmune diabetes in adults (LADA) is characterized by the presence of islet autoantibodies and initial insulin independence, which can lead to misdiagnosis of type 2 diabetes (T2D). As such, understanding the genetic etiology of LADA could aid in more accurate diagnosis. However, there is ongoing debate regarding the exact definition of LADA, so understanding its impact in different populations when contrasted with type 1 diabetes (T1D) and T2D is one potential strategy to gain insight into its etiology. Unfortunately, the lack of consistent and thorough autoantibody screening around the world has hampered well-powered genetic studies of LADA. This review highlights recent genetic and epidemiological studies of LADA in diverse populations as well as the importance of autoantibody screening in facilitating future research.

Latent Autoimmune Diabetes in Adults: Current Status and New Horizons

Autoimmune diabetes is a heterogeneous disease which can arise at any age. Subjects with adult-onset autoimmune diabetes who do not necessitate insulin-therapy for at least 6 months after diagnosis are demarcated as having latent autoimmune diabetes in adults (LADA). This condition is more heterogeneous than young-onset autoimmune diabetes and shares clinical and metabolic characteristics with both type 2 and type 1 diabetes. Patients with LADA are considered by having highly variable β-cell destruction, different degrees of insulin resistance and heterogeneous titre and pattern of islet autoantibody, suggesting different pathophysiological pathways partially explaining the heterogeneous phenotypes of LADA. To date the heterogeneity of LADA does not allow to establish a priori treatment algorithm and no specific guidelines for LADA therapy are available. These subjects are mostly treated as affected by type 2 diabetes, a factor that might lead to the progression to insulin-dependency quickly. A personalised medicine approach is necessary to attain optimal metabolic control and preserve β-cell function to decrease the risk of long-term diabetes complications. Recent data concerning the use of oral antidiabetic agents as dipeptidyl peptidase 4 inhibitors and glucagon-like peptide 1 receptor agonists indicate up-and-coming results in term of protect C-peptide levels and improving glycaemic control. This review summarises current knowledge on LADA, emphasising controversies regarding its pathophysiology and clinical features. Moreover, we discuss data available about novel therapeutic approaches that can be considered for prevention of β-cell loss in LADA.

Long-term effects on glycaemic control and β-cell preservation of early intensive treatment in patients with newly diagnosed type 2 diabetes: A multicentre randomized trial

AIM

To determine the effects of early intensive glycaemic control with intensive insulin treatment (IIT) or initial combined oral antidiabetic drug (COAD) therapy on long-term glycaemic control and the preservation of β-cell function in people with type 2 diabetes mellitus (T2DM).

METHODS

Newly diagnosed drug-naïve patients with T2DM from 8 outpatient diabetes centres were randomized to receive either IIT (n = 50; glargine/glulisine) or COAD (n = 47; glimepiride/metformin) as intensive treatment until the termination criteria to ensure euglycaemia were met. After intensive treatment, the patients completed a follow-up period with either lifestyle modification (LSM) alone or rescue therapy to maintain target glycated haemoglobin levels of <7% (53 mmol/mol) up to week 104. The primary outcomes were analysed after excluding participants who were anti-glutamic acid decarboxylase autoantibody-positive.

RESULTS

Both intensive treatment methods were effective for short-term glycaemic control, but improvements in the disposition index (DI) were significantly greater in the IIT group than in the COAD group (P = .021). During the follow-up period after intensive treatment, the two groups significantly differed in rescue method regarding the maintenance of comparable levels of glycaemic control (P = .010) and more participants who received IIT exhibited well-controlled glycaemia with LSM alone. Additionally, the IIT group maintained a higher DI than the COAD group during the follow-up period. Cox regression analysis showed that the IIT method was associated with a 52.5% lower risk of failing to maintain drug-free glycaemic remission compared with the COAD method (P = .015).

CONCLUSIONS

The findings indicate that outpatient clinic-based IIT to ensure euglycaemia in newly diagnosed patients with T2DM might be an effective initial therapeutic option for improvements in β-cell function and glycaemic control over the long term, without serious adverse events.

Clinical heterogeneity of type 1 diabetes (T1D) found in Asia

Diabetes mellitus among young patients in Asia is caused by a complex set of factors. Although type 1 diabetes (T1D) remains the most common form of diabetes in children, the recent unabated increase in obesity has resulted in the emergence of type 2 diabetes (T2D) as a new type of diabetes among adolescents and young adults. In addition to the typical autoimmune type 1 diabetes (T1aD) and T2D patients, there is a variable incidence of cases of non-autoimmune types of T1D associated with insulin deficiency (T1bD). Additional forms have been described, including fulminant T1D (FT1D). Although most diagnoses of T1D are classified as T1aD, fulminant T1D exists as a hyper-acute subtype of T1D that affects older children, without associated autoimmunity. Patient with this rare aetiology of diabetes showed a complete loss of β-cell secretory capacity without evidence of recovery, necessitating long-term treatment with insulin. In addition, latent autoimmune diabetes in adults is a form of autoimmune-mediated diabetes, usually diagnosed during the insulin-dependent stage that follows a non-insulin requiring phase, which can be diagnosed earlier based on anti-islet autoantibody positivity. Some reports discuss T1bD. Others are elaborating on the presence of "atypical T1b diabetes," such as Flatbush diabetes. The prevalence of diabetes mellitus in young adults continues to rise in Asian populations as T2D increases. With improved characterization of patients with diabetes, the range of diabetic subgroups will become even more diverse in the future. Distinguishing T1D, T2D, and other forms of diabetes in young patients is challenging in Asian populations, as the correct diagnosis is clinically important and has implications for prognosis and management. Despite aetiological heterogeneity in the usual clinical setting, early diagnosis and classification of patients with diabetes relying on clinical grounds as well as measuring islet autoantibodies and fasting plasma C-peptide could provide a possible viable method to minimize complications.

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

Diabetes mellitus is a chronic disorder caused by relative or absolute insulin deficiency and characterized by chronic hyperglycaemia. It is expected that by year 2025, 80% of all type 2 diabetic patients will be living in developing or low- and middle-income countries. Among Asians, there has been an overall increase in abdominal obesity; however, the risk of diabetes in these populations starts at much lower body mass index as compared to Caucasians. A significant proportion of diabetic patients with adult-onset, initially nonrequiring insulin treatment, have diabetes-associated autoantibodies in their sera. A new subclass of diabetes with the designation of latent autoimmune diabetes of adult-onset (LADA) has been proposed for this category of subjects. Studies have demonstrated that patients with autoimmune diabetes, characterized by the presence of glutamic decarboxylase autoantibodies display a different clinical phenotype from classical type 2 diabetes without glutamic decarboxylase autoantibodies. This subset of phenotypic type 2 diabetes subjects with islet autoantibodies tend to have sulphonylurea failure and need insulin treatment earlier in the disease process. Diagnosing LADA at an initial stage will be important so that insulin can be initiated earlier, facilitating improved glycemic control sooner as well as the preservation of residual beta-cell function in adult-onset autoimmune diabetes. Because of differences in dietary habits, environmental factors, and phenotypic characteristics between European and Asian populations, there may be heterogeneity in the prevalence and other characteristics of LADA in these two populations.

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

The prevalence of latent autoimmune diabetes in adults and its correlates in patients with type 2 diabetes in Kerman, Iran [2011]

INTRODUCTION

Latent autoimmune diabetes in adults [LADA] is a type of autoimmune diabetes in adults that is usually identified by positive GAD-antibody [glutamic acid decarboxylase]. Epidemiological studies show that this disease has no identified prevalence and incidence in Asia due to the various criteria in diagnosing the disease.

METHODS

500 patients with type 2 diabetes based on American Diabetes Association [ADA] criteria and age of diabetes onset above 35 years old who needed no insulin until at least 6 months after the diagnosis of diabetes were selected from KERCADR Study and their anti-GAD serum level was determined.

RESULTS

From 500 patients, 429 ones [85%] were negative and 71 ones [14.2%] were positive for GAD antibody. The prevalence of latent autoimmune diabetes was higher in the age group of 50-59 years compared to the other age groups. There was no significant correlation between LADA and hypertension, family history of diabetes, cigarette smoking and tobacco use.

CONCLUSION

The prevalence rate of latent autoimmune diabetes in adults in patients with type 2 diabetes was 14.2% and we could not find any relationship.

Zinc transporter 8 autoantibody (ZnT8A) could help differentiate latent autoimmune diabetes in adults (LADA) from phenotypic type 2 diabetes mellitus

BACKGROUND

The ZnT8A is an independent marker for diagnosis of type 1 diabetes mellitus. We investigated the distribution and clinical features of ZnT8A positive latent autoimmune diabetes in adult (LADA) patients to explore the potential diagnostic application.

METHODS

A total of 3062 phenotypic T2DM patients were randomly selected from a national multicenter study - the LADA China Study. Radioligand binding assays were applied to detect the presence of ZnT8A, GADA and IA-2A. HbA1c , fasting C-peptide and serum lipid levels were followed up with ZnT8A positive patients.

RESULTS

The positive prevalence of ZnT8A, GADA and IA-2A in phenotypic T2DM patients was 1.99% (61/3062), 6.43% (197/3062) and 1.96% (60/3062), respectively. The ZnT8A positivity was lower than that of GADA(x²  = 74.8, p < 0.001) but was comparable with that of IA-2A (p > 0.05). The positivity of ZnT8A in IA-2A positive patients was higher than that in GADA positive patients (38.3% vs. 10.7%, x²  = 24.8, p < 0.001). On the basis of GADA and IA-2A positivity, the ZnT8A assay enhanced the diagnostic prevalence of LADA from 7.58 to 8.62%. The LADA patients who were positive for ZnT8A had higher systolic blood pressure when compared with GADA positive cases (p = 0.049) and higher total cholesterol levels when compared with antibody-negative T2DM patients (p = 0.035).

CONCLUSION

The detection of ZnT8A at the basis of GADA and IA-2A can improve diagnostic sensitivity of Chinese LADA.

Latent autoimmune diabetes in adults in Asians: similarities and differences between East and West

Latent autoimmune diabetes in adults (LADA) is a form of autoimmune diabetes with features of both type 1 and type 2 diabetes and in the middle of the diabetes spectrum. Scientists clash on the question of whether this type of diabetes is a unique diabetes subtype. Multicenter studies have been performed in different countries, including the Korea National Diabetes Program (KNDP) collaboratory group, the Ehime study in Japan, the Not Insulin-Requiring Autoimmune Diabetes (NIRAD) study in Italy, the Nord-Trøndelag Health (HUNT) study in Norway, the UK Prospective Diabetes Study (UKPDS) in the UK, the Action LADA study in Europe and the LADA China study in China. These studies found universal immunogenetic effects associated with LADA, but with some ethnic differences. Herein we summarize those multicenter studies and compare the ethnic similarities and differences between East and West from epidemiological, clinical, immune, and genetic viewpoints.

Frequency, immunogenetics, and clinical characteristics of latent autoimmune diabetes in China (LADA China study): a nationwide, multicenter, clinic-based cross-sectional study

Adult non-insulin requiring diabetes includes latent autoimmune diabetes of adults (LADA), distinguished from type 2 diabetes by the presence of islet autoantibodies. LADA China determined the characteristics of Chinese LADA. This nationwide, multicenter, clinic-based cross-sectional study was conducted in 46 university-affiliated hospitals in 25 Chinese cities. All 4,880 ketosis-free diabetic patients (<1 year postdiagnosis, without insulin therapy for >6 months, aged ≥30 years) had GAD antibody (GADA) and HLA-DQ genotype measured centrally with clinical data collected locally. GADA-positive subjects were classified as LADA. Of the patients, 5.9% were GADA positive with LADA. LADA showed a north-south gradient. Compared with GADA-negative type 2 diabetes, LADA patients were leaner, with lower fasting C-peptide and less metabolic syndrome. Patients with high GADA titers are phenotypically different from those with low GADA titers, while only a higher HDL distinguished the latter from those with type 2 diabetes. HLA diabetes-susceptible haplotypes were more frequent in LADA, even in those with low-titer GADA. HLA diabetes-protective haplotypes were less frequent in LADA. Our study implicates universal immunogenetic effects, with some ethnic differences, in adult-onset autoimmune diabetes. Autoantibody positivity and titer could be important for LADA risk stratification and accurate therapeutic choice in clinical practice.

Inverse relationship of serum adiponectin concentration with type 2 diabetes mellitus incidence in middle-aged Japanese workers: six-year follow-up

BACKGROUND

It was suggested that inflammation may mediate or modify biological effects of adiponectin. Few studies examined the association between circulating adiponectin levels and type 2 diabetes (T2DM) while controlling for variables related to inflammation. In addition, East Asians were reported to have lower adiponectin levels but higher diabetes prevalence at a given degree of obesity than Caucasians, raising some possibility that the adiponectin-diabetes association may differ by race. Therefore, we prospectively investigated the associations with a number of covariates including C-reactive protein and smoking status in a cohort of Japanese workers aged 35-66 years.

METHODS

Serum adiponectin concentration and other covariates were obtained in 2002 for 3008 civil servants free of T2DM at baseline in urban/suburban Japan. T2DM incidence was defined as the year when annually assessed fasting blood glucose level first exceeded 126 mg/dL or self-reported initiation of medication through 2007. T2DM incidence was examined in relation to the adiponectin quintile.

RESULTS

Age- and sex-adjusted homeostasis model assessment insulin resistance was inversely associated with adiponectin quintiles at baseline. During six years of follow-up, 164 individuals developed T2DM. In a fully adjusted model, hazard ratios (95% confidence intervals) of T2DM in Q2 to Q5 compared with that in Q1 were 0.62 (0.41-0.94), 0.44 (0.25-0.77), 0.40 (0.20-0.78) and 0.85 (0.48-1.49), respectively.

CONCLUSIONS

Low adiponectin was related to increased incidence of T2DM independent of baseline levels of blood glucose, insulin and C-reactive protein as well as other confounding variables in middle-aged Japanese. Whether high adiponectin is linearly associated with decreased T2DM risk needs further investigation.