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

Consensus Guidance for Monitoring Individuals With Islet Autoantibody-Positive Pre-Stage 3 Type 1 Diabetes

Given the proven benefits of screening to reduce diabetic ketoacidosis (DKA) likelihood at the time of stage 3 type 1 diabetes diagnosis, and emerging availability of therapy to delay disease progression, type 1 diabetes screening programs are being increasingly emphasized. Once broadly implemented, screening initiatives will identify significant numbers of islet autoantibody-positive (IAb+) children and adults who are at risk for (confirmed single IAb+) or living with (multiple IAb+) early-stage (stage 1 and stage 2) type 1 diabetes. These individuals will need monitoring for disease progression; much of this care will happen in nonspecialized settings. To inform this monitoring, JDRF, in conjunction with international experts and societies, developed consensus guidance. Broad advice from this guidance includes the following: 1) partnerships should be fostered between endocrinologists and primary care providers to care for people who are IAb+; 2) when people who are IAb+ are initially identified, there is a need for confirmation using a second sample; 3) single IAb+ individuals are at lower risk of progression than multiple IAb+ individuals; 4) individuals with early-stage type 1 diabetes should have periodic medical monitoring, including regular assessments of glucose levels, regular education about symptoms of diabetes and DKA, and psychosocial support; 5) interested people with stage 2 type 1 diabetes should be offered trial participation or approved therapies; and 6) all health professionals involved in monitoring and care of individuals with type 1 diabetes have a responsibility to provide education. The guidance also emphasizes significant unmet needs for further research on early-stage type 1 diabetes to increase the rigor of future recommendations and inform clinical care.

Consensus guidance for monitoring individuals with islet autoantibody-positive pre-stage 3 type 1 diabetes

Given the proven benefits of screening to reduce diabetic ketoacidosis (DKA) likelihood at the time of stage 3 type 1 diabetes diagnosis, and emerging availability of therapy to delay disease progression, type 1 diabetes screening programmes are being increasingly emphasised. Once broadly implemented, screening initiatives will identify significant numbers of islet autoantibody-positive (IAb+) children and adults who are at risk of (confirmed single IAb+) or living with (multiple IAb+) early-stage (stage 1 and stage 2) type 1 diabetes. These individuals will need monitoring for disease progression; much of this care will happen in non-specialised settings. To inform this monitoring, JDRF in conjunction with international experts and societies developed consensus guidance. Broad advice from this guidance includes the following: (1) partnerships should be fostered between endocrinologists and primary-care providers to care for people who are IAb+; (2) when people who are IAb+ are initially identified there is a need for confirmation using a second sample; (3) single IAb+ individuals are at lower risk of progression than multiple IAb+ individuals; (4) individuals with early-stage type 1 diabetes should have periodic medical monitoring, including regular assessments of glucose levels, regular education about symptoms of diabetes and DKA, and psychosocial support; (5) interested people with stage 2 type 1 diabetes should be offered trial participation or approved therapies; and (6) all health professionals involved in monitoring and care of individuals with type 1 diabetes have a responsibility to provide education. The guidance also emphasises significant unmet needs for further research on early-stage type 1 diabetes to increase the rigour of future recommendations and inform clinical care.

A Review on Latent Autoimmune Diabetes in Adults

Latent autoimmune diabetes (LADA) is an unique form of diabetes that has characteristics of both type 1 and type 2 diabetes. Type 1.5 diabetes also known as LADA is occasionally confused for type 2 diabetes because there is delay in presenting features and early insulin independence. LADA, on the other hand, is an autoimmune disorder that differs from type 2 diabetes in that autoantibodies against pancreatic beta cells are what characterise it. Insulin production eventually diminishes due to the autoimmune destruction of pancreatic beta cells as a result of the pathophysiology of LADA. Autoantibodies to glutamic acid decarboxylase (GAD), islet antigen-2 (IA-2), and insulin are frequently detected in LADA patients. These autoantibodies have important implications for therapy strategies and are essential in differentiating LADA from type 2 diabetes. LADA clinical management is very challenging. The aim of this article is to view the characteristics, disease presentation, diagnostic challenges, progression and treatment modalities of LADA.

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.

The relationship between red blood cell distribution width and islet β-cell function indexes in patients with latent autoimmune diabetes in adults

AIMS

The objective of this study is to explore the relationship between red blood cell distribution and islet β-cell function indexes in patients with Latent Autoimmune Diabetes in Adults.

METHODS

A total of 487 LADA patients were enrolled in this cross-sectional study. Patients were divided into three groups according to RDW tertiles. Clinical and laboratory measurements of age, height, weight, duration of diabetes, blood pressure, RDW, glycosylated hemoglobin A1c (HbA1c), C-peptide and blood lipids were performed. Homeostasis model assessment of insulin resistance (HOMA-IR) and homeostasis model assessment of β-cell function (HOMA-β) were assessed using homeostasis model assessment (HOMA) based on fasting blood glucose (FBG) and fasting C-peptide index (FCP). Correlations and multiple linear regressions were implemented to determine the association of RDW and islet function indexes.

RESULTS

As the increase of serum RDW level, the presence of β-cell secretion increased(P < 0.05). Correlation analysis indicated that there were significant correlations between RDW and male sex, age, duration, TG, Cr, FCP, and HOMA-β in all subjects. Multiple linear regressions indicated that RDW was significantly correlated with HOMA-β in the total population in both unadjusted and adjusted analysis. This finding could be reproduced in the subgroup of low GAD titers for HOMA-β. RDW were significantly associated with HbA1c in LADA patients with high GAD titers, but the correlation was not found in subgroup with low GAD titers in either unadjusted analyses or adjusted analysis.

CONCLUSIONS

RDW is associated with β-cell function assessed by HOMA-β after adjusting for covariates in LADA patients with low GAD titers.

Prevalence of Positivity for Diabetes-Associated Autoantibodies in Individuals with Type 2 Diabetes and Their Further Characterisation: Cross-sectional Study from Slovakia

BACKGROUND

Individuals initially diagnosed with type 2 diabetes (T2D) might exhibit positivity for diabetes-associated autoantibodies (DAA +). We investigated the prevalence of DAA positivity in a group of individuals with T2D who were referred to a tertiary diabetes centre within a pre-specified period of time. We aimed to identify characteristics linked with DAA positivity by comparing DAA + individuals with their DAA-negative counterparts.

METHODS

This was a cross-sectional study into which all T2D patients referred to the National Institute of Endocrinology and Diabetology, Ľubochňa, Slovakia, between 1 January and 30 June 2016 were included. Data on > 70 participants' characteristics, including antibodies against glutamic acid decarboxylase (anti-GAD₆₅), insulinoma-associated antigen IA-2 (IA-2A) and insulin (IAA), were collected.

RESULTS

Six hundred and ninety-two individuals (387, 55.6% female) with a median (range) age of 62 (24-83) years, HbA1c of 8.9 (5.0-15.7)% [74 (31-148 mmol/mol)] and diabetes duration of 13.0 (0-42) years were analysed. One hundred and forty-five (145/692, 21.0%) tested positive for at least one DAA; 136/692 (19.7%) were positive for anti-GAD₆₅, 21/692 (3.0%) were positive for IA-2A and 9/692 (1.3%) were positive for IAA. Only 84.9% of the DAA + individuals aged > 30 years at the time of diabetes diagnosis met the current diagnostic criteria for latent autoimmune diabetes of adults (LADA). DAA + differed from DAA - individuals in multiple characteristics, including the incidence of hypoglycaemia.

CONCLUSION

Several pathological processes linked with distinct types of diabetes can develop in parallel, including insulin resistance and autoimmune insulitis. In this single-centre cross-sectional study from Slovakia, we report a higher than previously published prevalence of DAA positivity in a group of individuals with a formal diagnosis of T2D.

Clarifying the Heterogeneity in Response to Vitamin D in the Development, Prevention, and Treatment of Type 2 Diabetes Mellitus: A Narrative Review

In this review, we explore the potential drivers of heterogeneity in response to Vitamin D (VitD) therapy, such as bioavailability, sex-specific response, and autoimmune pathology, in those at risk for and diagnosed with T2DM. In addition, we propose distinct populations for future interventions with VitD. The literature concerning VitD supplementation in the prevention, treatment, and remission of type 2 diabetes mellitus (T2DM) spans decades, is complex, and is often contradictory with mixed findings upon intervention. By association, VitD status is powerfully predictive with deficient subjects reporting greater risk for T2DM, conversion to T2DM from prediabetes, and enhanced response to VitD therapy. Preclinical models strongly favor intervention with VitD owing to the pleiotropic influence of VitD on multiple systems. Additional research is crucial as there remain many questions unanswered that are related to VitD status and conditions such as T2DM. Future research must be conducted to better understand the potentially spurious relationships between VitD status, supplementation, sun exposure, health behaviors, and the diagnosis and management of T2DM. Public health practice can greatly benefit from a better understanding of the mechanisms by which we can reliably increase VitD status and how this can be used to develop education and improve health behaviors.

Identification and phenotypic characterization of patients with LADA in a population of southeast Mexico

Latent autoimmune diabetes in adults (LADA) has clinical and metabolic features of type 1 and type 2 diabetes. LADA does not have specific features for its diagnosis apart from autoantibody detection; however, these tests are not affordable in clinical settings. In this cross-sectional study, we analyzed clinical criteria, metabolic control, pharmacological treatment, and diabetic complications in two groups of patients with diabetes -LADA and T2D- in order to identify specific characteristic of these clinical entities. Finally, we evaluated if the estimated glucose disposal rate (eGDR) and age at diagnosis of diabetes could be used as a diagnostic criterion for LADA. Demographic, biochemical, clinical and treatment were measured in 377 individuals with diabetes. The diagnostics of LADA were determined using Glutamic acid decarboxylase autoantibodies levels. Chi-square test or t-Student test were used to establish differences between groups. To identify factors associated with LADA, a logistic regression analysis was used. Finally, a ROC curve was plotted to assess the possible variables as diagnostic criteria for LADA. The 377 patients with diabetes were separated into 59 patients with LADA and 318 patients with T2D. Patients with LADA showed lower fasting glucose values, fewer diabetic complications, younger age at diagnosis of diabetes, higher insulin use, and higher eGDR in comparison to patients with T2D. Both groups had a mean BMI classified as overweight. The ROC evaluated the sensitivity and specificity, this analysis indicated that an age younger than 40.5 years and an eGDR value higher than 9.75 mg/kg/min correlated better with LADA. These parameters could be useful to identify patients suspected to have LADA at the first level of medical care in the population of southeastern Mexico and refer them to a second level of care.

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.

Type 1 and other types of diabetes mellitus in the perioperative period. What the anaesthetist should know

Diabetes mellitus is often treated as a uniform disease in the perioperative period. Type 2 diabetes is most commonly encountered, and only a minority of surgical patients have been diagnosed with another type of diabetes. Patients with a specific type of diabetes can be particularly prone to perioperative glycaemic dysregulation. In addition, certain type-related features and pitfalls should be taken into account in the operating theatre. In this narrative review, we discuss characteristics of types of diabetes other than type 2 diabetes relevant to the anaesthetist, based on available literature and data from our clinic.

Latent Autoimmune Diabetes in an Adult Male Presenting With Diabetic Ketoacidosis (DKA)

Latent autoimmune diabetes in adults (LADA) is a common but not well-studied entity and its features overlap between type 1 and type 2 diabetes mellitus (T1D, T2D). Although autoimmunity is a well-known factor associated with this diabetes subtype, environmental factors including excessive weight, physical inactivity, and smoking may also be associated with it. It is commonly misdiagnosed as T2D and generally treated by oral anti-diabetes medications that cause a delay in commencing insulin therapy. There are few cases mentioned in the literature of LADA presenting first time as diabetic ketoacidosis (DKA). Here, we report a case of latent autoimmune diabetes in an adult male who presented with DKA.

Diagnostic Dilemmas and Current Treatment Approaches in Latent Onset Autoimmune Diabetes in Adults: A Concise Review

Latent Onset Autoimmune Diabetes in Adults (LADA) is an autoimmune disorder between T1DM and T2DM and is often misdiagnosed as T2DM due to its late-onset. The disease is characterized by β-cell failure and slow progression to insulin dependence. Early diagnosis is significant in limiting disease progression. C-peptide levels and autoantibodies against β-cells are the most critical diagnostic biomarkers in LADA. The review aims to provide an overview of the biomarkers used to diagnose LADA, and the following treatment approaches. We have summarized LADA's pathophysiology and the autoantibodies involved in the condition, diagnostic approaches, and challenges. There are clear shortcomings concerning the feasibility of autoantibody testing. Finally, we have explored the treatment strategies involved in the management of LADA. In conclusion, the usual management includes treatment with metformin and the addition of low doses of insulin. Newer oral hypoglycaemic agents, such as GLP-1RA and DPP-4 inhibitors, have been brought into use. Since the disease is not entirely understood at the research level and in clinical practice, we hope to encourage further research in this field to assess its prevalence. Large randomized controlled trials are required to compare the efficacy of different available treatment options.

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 ).

Clinical characteristics and cardiovascular risk profile in children and adolescents with latent autoimmune diabetes: Results from the German/Austrian prospective diabetes follow-up registry

AIMS

To characterize children and adolescents with latent autoimmune diabetes of the young (LADY), and to assess the utility of classifying individuals as LADYs regarding their cardiovascular (CV) risk factors.

METHODS

Data from 25,520 individuals (age at diagnosis <18 years) of the Prospective Diabetes Follow-up Registry Diabetes-Patienten Verlaufsdokumentation (DPV) were analyzed. LADY was defined as positivity of ≥one islet autoantibody (iAb+) and an insulin-free interval of ≥6 months upon diabetes diagnosis. LADYs were compared to iAb+ individuals immediately requiring insulin ("immunologically confirmed" type 1 diabetes, T1DM), iAb-/Ins- individuals ("classical" T2DM) and to those clinically defined as T2DM (iAbs not measured).

RESULTS

Clinical characteristics of LADYs (n = 299) fell in between those with T1DM (n = 24,932) and T2DM (iAb-/Ins-, n = 152) or suspected T2DM (iAB not measured, n = 137). Stratifying LADYs according to their clinical diagnosis however revealed two distinct populations, highly resembling either T1DM or T2DM. Particularly, CV risk profile, precisely prevalence rates of arterial hypertension and dyslipidemia, was significantly higher in LADYs clinically classified as T2DM compared to LADYs classified as T1DM, and did not differ from those with "classical" T2DM.

CONCLUSIONS

In terms of CV risk, classifying children and adolescents with diabetes as LADYs provides no additional benefit. Instead, clinical diagnosis seems to better assign individuals to appropriate risk groups for increased CV risk profiles.

Adult-onset type 1 diabetes: A changing perspective

Type 1 diabetes most commonly presents in adulthood, contrary to the widely held view that it is a disease of childhood. Furthermore, a substantial proportion of cases of adult-onset type 1 diabetes does not require insulin therapy at clinical onset. Recent studies have emphasised the evidence that adult-onset type 1 diabetes is prevalent but often misclassified initially as type 2 diabetes (1, 2). In this review, we discuss that recent literature, highlighting the similarities and differences between adult-onset and childhood-onset type 1 diabetes, exploring recent debates surrounding its epidemiology and genetics, as well as expanding on important issues of diagnostic criteria for individuals presenting with adult-onset diabetes and the subsequent management once identified as having an autoimmune basis. In addition, this review looks at the psychosocial challenges faced by T1D patients and their possible management.

Adult-onset autoimmune diabetes

Adult-onset autoimmune (AOA) diabetes pathophysiology starts with immune changes, followed by dysglycaemia and overt disease. AOA diabetes can occur as classic type 1 diabetes when associated with severe loss of insulin secretion. More frequently, it is diagnosed as latent autoimmune diabetes in adults, a slowly progressing form with late onset, a long period not requiring insulin, and it is often misdiagnosed as type 2 diabetes. As its clinical presentation varies remarkably and immune markers often lack specificity, it is challenging to classify each case ad hoc, especially when insulin treatment is not required at diagnosis. Proper care of AOA diabetes aims to prevent complications and to improve quality of life and life expectancy. To achieve these goals, attention should be paid to lifestyle factors, with the aid of pharmacological therapies properly tailored to each individual clinical setting. Given the heterogeneity of the disease, choosing the right therapy for AOA diabetes is challenging. Most of the trials testing disease-modifying therapies for autoimmune diabetes are conducted in people with childhood onset, whereas non-insulin diabetes therapies have mostly been studied in the larger population with type 2 diabetes. More randomized controlled trials of therapeutic agents in AOA diabetes are needed.

Effects of rosuvastatin on serum glucose and insulin in hyperuricemic rats

Background

Hyperuricemia is a state in which the serum levels of uric acid (UA) are elevated. This study was to determine the roles of rosuvastatin in fasting blood glucose (FGB) and insulin levels in hyperuricemic rats.

Methods

Thirty-six Sprague-Dawley (SD) rats were randomized divided into the control, model and rosuvastatin groups: the control was given no intervention, the model group was established by administrating yeast extract powder and oxonic acid potassium salt, and the rosuvastatin group was given intravenous administration of rosuvastatin for 28 days in hyperuricemic rats. Serum uric acid (SUA), fasting blood glucose (FBG), fasting blood insulin (FBI), glutamic acid decarboxylase antibody (GADA), oral glucose tolerance test (OGTT) levels, and the ultrastructure of pancreatic β-cells were measured. Also, homeostasis model assessment of insulin resistance (HOMA-IR) scores was computed in three groups.

Results

Compared to the model group, SUA were decreased, while the FBG, GADA, OGTT and HOMA-IR at week 4 were significantly increased in rosuvastatin group. However, FBI was not significantly changed between three groups. It was also showed that the structure of pancreatic β-cells was damaged and the number of β-cells was changed in hyperuricemic rats while they were aggravated in rosuvastatin group.

Conclusion

Rosuvastatin has roles in inducing FGB, GADA, OGTT and pancreatic β-cells damage in hyperuricemic rats.

Predicting misdiagnosed adult-onset type 1 diabetes using machine learning

AIMS

It is now understood that almost half of newly diagnosed cases of type 1 diabetes are adult-onset. However, type 1 and type 2 diabetes are difficult to initially distinguish clinically in adults, potentially leading to ineffective care. In this study a machine learning model was developed to identify type 1 diabetes patients misdiagnosed as type 2 diabetes.

METHODS

In this retrospective study, a machine learning model was developed to identify misdiagnosed type 1 diabetes patients from a population of patients with a prior type 2 diabetes diagnosis. Using Ambulatory Electronic Medical Records (AEMR), features capturing relevant information on age, demographics, risk factors, symptoms, treatments, procedures, vitals, or lab results were extracted from patients' medical history.

RESULTS

The model identified age, BMI/weight, therapy history, and HbA1c/blood glucose values among top predictors of misdiagnosis. Model precision at low levels of recall (10 %) was 17 %, compared to <1 % incidence rate of misdiagnosis at the time of the first type 2 diabetes encounter in AEMR.

CONCLUSIONS

This algorithm shows potential for being translated into screening guidelines or a clinical decision support tool embedded directly in an EMR system to reduce misdiagnosis of adult-onset type 1 diabetes and implement effective care at the outset.

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.

Diabetic ketoacidosis as first presentation of latent autoimmune diabetes in adults in a patient with hashitoxicosis as first presentation of Hashimoto's thyroiditis: a case report

Background

Latent autoimmune diabetes in adults is an infrequent form of autoimmune diabetes mellitus, while Hashimoto’s thyroiditis, the most common thyroid disease in adults, rarely manifests as thyrotoxicosis. The concurrent initial presentation of these two autoimmune disorders is extremely rare.

Case presentation

A 29-year-old male of Albanian descent presented after being hospitalized owing to diabetic ketoacidosis. The diagnosis of type 1 diabetes mellitus was placed, and intensified insulin therapy was initiated. Medical history was not of significance except a 5 kg weight loss within 2 months. The patient presented with recurrent episodes of hypoglycemia, and the doses of preprandial and basal insulin were reduced. The differential diagnosis included type 1 diabetes mellitus “honeymoon” period or another type of diabetes mellitus. His serological tests only revealed positive autoantibodies against glutamic acid decarboxylase 65 and C-peptide. The diagnosis leaned toward latent autoimmune diabetes in adults, and the therapeutic approach involved cessation of preprandial insulin therapy, regulation, and subsequent discontinuation of basal insulin and introduction of metformin. Two years later, basal insulin was reintroduced along with a glucagon-like peptide-receptor agonist and metformin. Further physical examination during the initial visit disclosed upper limb tremor, lid lag, excessive sweating, increased sensitivity to heat, and tachycardia. Laboratory tests were indicative of hashitoxicosis (suppressed level of thyroid-stimulating hormone, high levels of total and free thyroid hormones, positive anti-thyroglobulin and anti-thyroid peroxidase, and negative anti-thyroid-stimulating hormone receptor). Thyroid-stimulating hormone level was spontaneously restored, but an increase was observed during follow-up. Levothyroxine was administrated for 2 years until the patient had normal thyroid function.

Conclusions

The prevalence of thyroid autoantibodies in patients with latent autoimmune diabetes in adults ranges from 20% to 30%. This correlation can be attributed to genetic involvement as well as disorders of immune tolerance to autoantigens. Hence, this report gives prominence to the holistic approach and consideration of comorbidities in patients with diabetes mellitus.

Sphingomyelin profiling in patients with diabetes could be potentially useful as differential diagnostics biomarker: A pilot study

PURPOSE

Autoimmune diabetes (AD) in adults includes both the classical form of type 1 diabetes mellitus (T1DM) and latent autoimmune diabetes in adults (LADA). LADA shares clinical and metabolic features with type 1 and type 2 diabetes mellitus (T2DM). Ceramide (Cer) levels negatively correlate with insulin sensitivity in humans and animal models. However, only a few studies have focused on other sphingolipids, including sphingomyelin (SM). Therefore, we determined sphingolipids in patients with newly diagnosed diabetes as possible diagnostic biomarkers.

MATERIALS AND METHODS

We evaluated sphingolipids in a cohort of 59 adults with newly diagnosed diabetes without prior hypoglycemic pharmacotherapy to distinguish diabetes mellitus types and for precise LADA definition. All patients with newly diagnosed diabetes were tested for the concentrations of individual Cer and SM species by gas-liquid chromatography. The study included healthy controls and patients with T1DM, T2DM and LADA.

RESULTS

SM species were significantly altered in patients with newly diagnosed diabetes compared to healthy controls. SM-C16:0, C16:1, -C18:0, -C18:1, -C18:2, -C18:3, -C20:4, and -C22:6 species were found to be significantly elevated in LADA patients. In contrast, significant differences were observed for Cer species with saturated acyl chains, especially Cer-C14:0, -C16:0, -C18:0 (AD and T2DM), -C22:0, and -C24:0 (T1DM). Following ROC analysis, SM-C16:0, and particularly -C18:1, and -C20:4 may be supportive diagnostic markers for LADA.

CONCLUSION

SM profiling in patients with newly diagnosed diabetes could be potentially helpful for differential diagnosis of LADA, T1DM, and T2DM in more challenging cases.

Lifestyle or Environmental Influences and Their Interaction With Genetic Susceptibility on the Risk of LADA

Background

LADA is a common form of diabetes described as a mix between type 1 and type 2 diabetes. Understanding of how genes and environmental factors interact in the development of LADA is central for future efforts to prevent the disease. This review aims to synthesize the literature on lifestyle factors linked to LADA risk and discuss their potential interaction with genetic susceptibility.

Findings

Current knowledge on environmental risk factors for LADA is primarily based on observational data from Scandinavian populations. Increasing evidence suggest that lifestyle factors promoting type 2 diabetes such as obesity, sedentariness, low birth weight and smoking, is implicated in the risk of LADA. Data from mendelian randomization studies support that the link between LADA and obesity, low birth weight and smoking is causal. Limited evidence indicates that dietary factors including consumption of red meat, coffee and sweetened beverages may increase the risk while consumption of alcohol and omega-3 fatty acids may reduce the risk. Several lifestyle factors, including smoking and obesity, seem to interact with human leukocyte antigen genes associated with autoimmunity, conferring much stronger effects on disease risk among those exposed to both factors.

Summary

Available studies suggest that lifestyle modification has the potential for prevention of LADA, particularly for individuals with high risk of disease such as those with genetic susceptibility. Research into risk factors of LADA is however limited, confirmations are warranted, many factors remain to be explored, and there is a need for intervention studies to assess causality.

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.

Endocrine Manifestations and New Developments in Mitochondrial Disease

Mitochondrial diseases are a group of common inherited diseases causing disruption of oxidative phosphorylation. Some patients with mitochondrial disease have endocrine manifestations, with diabetes mellitus being predominant but also include hypogonadism, hypoadrenalism, and hypoparathyroidism. There have been major developments in mitochondrial disease over the past decade that have major implications for all patients. The collection of large cohorts of patients has better defined the phenotype of mitochondrial diseases and the majority of patients with endocrine abnormalities have involvement of several other systems. This means that patients with mitochondrial disease and endocrine manifestations need specialist follow-up because some of the other manifestations, such as stroke-like episodes and cardiomyopathy, are potentially life threatening. Also, the development and follow-up of large cohorts of patients means that there are clinical guidelines for the management of patients with mitochondrial disease. There is also considerable research activity to identify novel therapies for the treatment of mitochondrial disease. The revolution in genetics, with the introduction of next-generation sequencing, has made genetic testing more available and establishing a precise genetic diagnosis is important because it will affect the risk for involvement for different organ systems. Establishing a genetic diagnosis is also crucial because important reproductive options have been developed that will prevent the transmission of mitochondrial disease because of mitochondrial DNA variants to the next generation.

Relation between the insulin lowering rate and changes in bone mineral density: Analysis among subtypes of type 1 diabetes mellitus

AIMS/INTRODUCTION

Bone mineral density (BMD) in patients with type 1 diabetes mellitus (T1DM) is reduced due to impaired insulin secretion. However, it is unclear whether the rate of BMD reduction is affected by T1DM subtypes. This study aimed to clarify the difference in BMD across T1DM subtypes: slowly progressive (SP), acute-onset (AO), and fulminant (F).

METHODS

This was a retrospective, single-center, cross-sectional study conducted on 98 adult T1DM patients. The main outcome included the BMD Z-score (BMD-Z) measured at the lumbar spine (LS) and femoral neck (FN).

RESULTS

The LS BMD-Z was lower in the AO than in the SP (p =0.03). No differences were observed when compared to the F. The FN BMD-Z tended to be higher in the SP than in the AO and F. Multiple regression analyses showed that the LS BMD-Z was associated with subtypes (AO vs. SP) (p =0.01), but not subtypes (F vs. SP), adjusted for sex, duration, retinopathy, and C-peptide immunoreactivity (CPR). When patients were divided into disease duration tertiles, in the first and second tertiles, the CPR levels were lower in the AO or F than in the SP. In contrast, LS and FN BMD-Z differed between the AO and SP only in the second tertiles (both p <0.01), with a similar tendency between the F and SP.

CONCLUSIONS

Among T1DM subtypes, BMD has time-dependent changes, which reveals that BMD decline follows impaired insulin secretion. These results provide novel insights into the association between the low insulin exposure duration and BMD.

Screening Strategy for Islet Autoantibodies in Diabetes Patients of Different Ages

Background: The detection of islet autoantibodies is essential for the accurate classification and diagnosis of diabetes mellitus (DM). The islet autoantibody distribution varies by age. However, screening strategies for DM patients with different onset ages remain lacking. Materials and Methods: This cross-sectional study included 17,536 DM patients from 46 medical centers across China. The seroprevalence of glutamic acid decarboxylase autoantibody (GADA), insulinoma-associated-2 autoantibody (IA-2A), zinc transporter 8 autoantibody (ZnT8A), and insulin autoantibody (IAA) was determined in younger and older patients with type 1 DM (T1DM) (n = 287 and 285, respectively), younger and older patients with latent autoimmune diabetes (LAD) (n = 140 and 121, respectively), and younger and older patients with type 2 DM (n = 200 in each group). Results: The cutoff age between younger and older patients was 35 years using restricted cubic spline method (n = 17,536, adjusted R² = 0.97, residual standard error = 1.32; P < 0.001). The seroprevalence rates of four islet autoantibodies were higher in patients aged 15-35 years than in those ≥35 years (GADA: 17% vs. 5.6%, IA-2A: 8.5% vs. 1.3%, ZnT8A: 6.3% vs. 2.3%, IAA: 2.2% vs. 1.0%). The prevalence of ZnT8A was higher in LAD patients than in T1DM patients, especially in older LAD patients. The results indicated that ZnT8A detection can increase the detection rate of older LAD patients from 70.2% (based on GADA detection alone) to 91.7%. Conclusions: In patients stratified according to the cutoff age of 35 years, the optimal detection sequence should be GADA, IA-2A, and ZnT8A in younger patients and GADA, ZnT8A, and IA-2A in older patients, so as to reduce the screening cost while improving the detection rate. Particularly, the ZnT8A test is recommended in older patients to avoid a missed LAD diagnosis.

Two Fifth-Generation Fighter Pilots Discovered with Latent Autoimmune Diabetes

BACKGROUND: Fighter pilots undergo extensive medical screening but may still miss rare diseases like latent autoimmune diabetes in adults (LADA). LADA patients have circulating autoantibodies directed against pancreatic beta cell antigens and present with frank diabetes late in life which may elude conventional military flight screening.CASE REPORT: Two fifth-generation fighter pilots, a 38-yr-old man (patient 1) and a 27-yr-old man (patient 2), with no significant past medical histories developed symptoms of fatigue, weight loss, episodic polyuria, and arthralgia. Patient 1's symptoms were initially thought to have been caused by COVID-19, but he subsequently tested negative for viral infection. Lab work instead showed elevated TSH, HgbA1C 11.4%, positive GAD-65, anti-TPO, and anti-islet cell antibodies. Patient 2 developed symptoms following a military deployment and a 72-h diarrheal illness. Due to flight status, patient 2 did not seek expert medical attention for several months, but lab work found HgbA1C of 10.4%, positive GAD-66, and ZnT8 antibodies. Both patients were started on insulin therapy. Patient 1 was also started on levothyroxine for hypothyroidism and retired from flying duties. Patient 2 eventually transitioned to metformin without insulin and returned to flying duties with an aeromedical waiver.DISCUSSION: Our patients maintained peak physical fitness throughout their selection and aviation careers, which likely delayed their clinical presentation. Current USAF flight rules prohibit insulin use with flying fighter aircraft. Early antibody screening during pilot selection may be a cost-effective means of diagnosis as traditional screening techniques are unlikely to detect LADA.Zhang JX, Berry J, Kim NM, Gray JJ, Fotheringham S, Sauerwein TJ. Two fifth-generation fighter pilots discovered with latent autoimmune diabetes. Aerosp Med Hum Perform. 2022; 93(2):106-110.

Characteristic phenotype of Chinese patients with adult-onset diabetes who are autoantibody positive by 3-Screen ICA™ ELISA

AIMS

To assess the prevalence of diabetes-associated autoantibodies in Chinese patients recently diagnosed with adult-onset diabetes and to evaluate the potential role of the autoantibody markers for characterization of disease phenotype in the patient population.

METHODS

The study included 1273 recent-onset adult patients with phenotypic type 2 diabetes mellitus (T2DM). Serum samples were tested using the 3-Screen ICA™ ELISA (3-Screen) designed for combined measurement of GADAb and/or IA-2Ab and/or ZnT8Ab. 3-Screen positive samples were then tested for individual diabetes-associated and other organ-specific autoantibodies. Clinical characteristics of patients positive and negative in 3-Screen were analysed.

RESULTS

Forty-four (3.5%) of the T2DM patients were positive in 3-Screen, and 38 (86%) of these were also positive for at least one of GADAb, IA-2Ab and ZnT8Ab in assays for the individual autoantibodies. 3-Screen positive patients had lower BMI, higher HbA1c, lower fasting insulin levels and lower fasting C-peptide levels compared to 3-Screen negative patients. Analysis using a homeostatic model assessment (HOMA2) indicated that HOMA2-β-cell function was significantly lower for the forty-four 3-Screen positive patients compared to 3-Screen negative patients. Twenty (45%) 3-Screen positive patients were also positive for at least one thyroid autoantibody.

CONCLUSIONS

The 3-Screen ELISA has been used successfully for the first time in China to detect diabetes autoantibodies in patients with phenotypic T2DM. 3-Screen positive patients presented with poorer β cell function.

Investigation of serum level relationship anti-glutamic acid decarboxylase antibody and inflammatory cytokines (IL1-β, IL-6) with vitamins D in type 2 diabetes

Background

Various factors are involved in the development and progression of diabetes mellitus, from cytokines and autoimmune destruction of pancreatic beta cells to vitamin D.This study aimed to investigate the association of serum levels of anti-glutamic acid decarboxylase (anti-GAD) and inflammatory cytokines with vitamin D in type 2 diabetes (T2D).

Methods

This case-control study was performed on 30 patients with T2D and 30 healthy individuals in Mashhad hospitals in 2020. Lipid profile, creatinine, uric acid, FBS, HbA1c, and blood pressure were recorded. All study variables were measured, particularly serum vitamin D, anti-GAD, and inflammatory cytokine levels in diabetic patients, and the data were compared to those from healthy subjects by performing an appropriate statistical analysis.

Results

Diabetic patients with a mean age of 52.9 ± 10.4 years, including 16 women and healthy individuals with a mean age of 48.5 ± 10.4 years, including 16 women, were studied. BMI level (P = 0.002), systolic blood pressure (P = 0.034), HbA1c, insulin, IL-6, IL1-β, anti-GAD levels, and insulin resistance in diabetic patients were significantly higher than the control group (P = 0.001). The vitamin D level in the control group was significantly higher than in the case group (P = 0.0001). The results showed a significant direct relationship between IL-6, IL-1β, and anti-GAD with HbA1c, FBS, insulin, and insulin resistance. However, there was a significant inverse relationship between IL-6, IL-1β, and anti-GAD with vitamin D.

Conclusions

Inflammatory cytokines and anti-GAD and vitamin D are associated with diabetes, and thus controlling these factors can help improve T2D.

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.

Fatty Acid Profiles and Their Association With Autoimmunity, Insulin Sensitivity and β Cell Function in Latent Autoimmune Diabetes in Adults

BACKGROUND

The pathogenesis of the progressive loss of beta cell function latent autoimmune diabetes in adults (LADA) remains still elusive. We aim to study the fatty acid (FA) profile in LADA.

SUBJECTS AND METHODS

Data from 116 patients with diabetes and GADA and 249 diabetes controls without GADA selected by Propensity Score Matching were collected. FA was analyzed with liquid chromatography-tandem mass spectrometry analysis.

RESULTS

Principal factor analysis found component 1 explains 82.6% of total variance contained fatty acids from a mixed of lard oil, seafood, and vegetable diet, followed by diet predominantly from vegetable oil, a diet of high fat diet, and a diet of seafood diet. The FA heatmap looked clearly different among the three groups with more similar type 1 (t1dm) and LADA fatty acid profile. n-3 α-linolenic acid (ALA), n-3 long chain polyunsaturated fatty acid (n-3 LC-PUFA), such as Eicosapentaenoic Acid and Docosapentaenoic Acid, n-3/n-6 ratio and triene/tetraene ratio were higher in patients with type 2 diabetes (t2dm) compared with LADA and t1dm. Saturated FAs were lower in t2dm than t1dm and LADA. Arachidic acid and n-6 LC-PUFAs were lower in t2dm than in t1dm and LADA. The characteristics of FAs in LADA were in between of classical t1dm and t2dm. Patients were classified into 6 clusters by FA clusters. Only cluster 2, 3, 5 contained enough patients to be analyzed. Cluster 5 showed an insulin deficient phenotype containing more than 60% of patients with t1dm and LADA and only 12.8% of t2dm. Cluster 2 and 3 were similar. β cell function and glycemic control was better in cluster 3 homing 25% of t2dm. Cluster 2 held 28% of t1dm and LADA, in this cluster more than 60% of patients was t2dm. n-3 linolenic acid, n-3 LC-PUFAs, some n-6 LC-PUFAs, n-3/n-6 ratio and triene/tetraene ratio were negatively associated with GADA positivity while n-6 Arachidonic Acid was associated positively with GADA. Similar findings were found for insulin sensitivity and beta cell function.

CONCLUSION

PUFA are associated with insulin sensitivity and beta cell function, and like other clinical features, FA profile distributed differently, but could not be used as makers to differentiate LADA from t1dm and t2dm.

ETHICS AND DISSEMINATION

This study has been approved by the Ethical Review Committee of Second Hospital of Dalian Medical University (approval number: 2021-005).

CLINICAL TRIAL REGISTRATION

none.

Effects of Berberine Plus Inulin on Diabetes Care in Patients With Latent Autoimmune Diabetes in Adults: Protocol for a Randomized Controlled Trial

BACKGROUND

Latent autoimmune diabetes in adults (LADA) is a heterogeneous form of diabetes, characterized by autoimmune destruction of pancreatic β-cells as well as insulin resistance and is triggered by environmental factors in the context of genetic susceptibility. Berberine (BBR), a small alkaloid isolated from medicinal plants, has antidiabetic, anti-inflammatory, and antibacterial effects. Inulin is a common prebiotic that has been shown to improve glycemic control, alter the gut microbiota and suppress inflammation. The primary purpose of this study was to evaluate the effects of oral BBR and inulin combined with insulin therapy on diabetes care in patients with LADA.

METHODS AND ANALYSIS

We will conduct a single-center, prospective, randomized, double-blind, placebo-controlled trial. A total of 240 patients with LADA who have started insulin therapy will be randomly allocated either to the intervention or control group. After a 1-week run-in period, they will complete a 3-month treatment of BBR alone, inulin plus BBR, inulin alone, or placebo. Anthropometric and clinical data will be collected at five time points: baseline, 3 months, 6 months, 9 months, and 12 months from baseline. The primary outcome was the change in glycated hemoglobin levels. Dynamic blood glucose parameters, β-cell function, and gut microbiota, as well as adverse events and quality of life will be monitored.

DISCUSSION

Glycemic control is critical for preventing the progression of diabetes. Although insulin is a recommended treatment for patients with LADA, there are currently no drugs that can effectively prevent the progressive destruction of pancreatic β-cells or maintain their function. Several studies have found that when berberine and prebiotics are used alone, they have beneficial metabolic effects. This clinical research protocol will assess the efficacy of the combined treatment of berberine plus inulin and provide new ideas for future pharmacological research and clinical practices in diabetes care and glycemic control for LADA patients.

ETHICS AND DISSEMINATION

This study has been approved by the Ethics Committee of National Clinical Research Center of the Second Xiangya Hospital of Central South University (approval number: 2021-046).

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, identifier NCT04698330.

Latent autoimmune diabetes in adults: a focus on β-cell protection and therapy

Latent autoimmune diabetes in adults (LADA) is a heterogeneous disease sharing some phenotypic, genetic, and immunological features with both type 1 and 2 diabetes. Patients with LADA have a relatively slow autoimmune process and more residual islet β-cell function at onset, allowing a time window to protect residual islet β cells and delay or inhibit disease progression. It is crucial to discover various heterogeneous factors affecting islet β-cell function for precise LADA therapy. In this review, we first describe the natural history of LADA. Thereafter, we summarize β-cell function-related heterogeneous factors in LADA, including the age of onset, body mass index, genetic background, and immune, lifestyle, and environmental factors. In parallel, we evaluate the impact of current hypoglycemic agents and immune intervention therapies for islet β-cell protection. Finally, we discuss the opportunities and challenges of LADA treatment from the perspective of islet β-cell function protection.

Innate immunity in latent autoimmune diabetes in adults

Latent autoimmune diabetes in adults (LADA) is an autoimmune disease that shares some genetic, immunological and clinical features with both type 1 diabetes and type 2 diabetes. Immune cells including CD4⁺ T cells, CD8⁺ T cells, B cells, macrophages and dendritic cells (DCs) have been detected in the pancreas of patients with LADA and a rat model of LADA. Therefore, similar to type 1 diabetes, the pathogenesis of LADA may be caused by interactions between islet β-cells and innate and adaptive immune cells. However, the role of the immunity in the initiation and progression of LADA remains largely unknown. In this review, we have summarized the potential roles of innate immunity and immune-modulators in LADA development. Furthermore, we have examined the evidence and discussed potential innate immunological reasons for the slower development of LADA compared with type 1 diabetes. More in-depth mechanistic studies are needed to fully elucidate the roles of innate immune-associated genes, molecules and cells in their contributions to LADA pathogenesis. Undertaking these studies will greatly enhance the development of new strategies and optimization of current strategies for the diagnosis and treatment of the disease.

Serum Bile Acid Profiles in Latent Autoimmune Diabetes in Adults and Type 2 Diabetes Patients

BACKGROUND

Impaired bile acid (BA) metabolism has been associated with the progression of type 2 diabetes (T2D). However, the contribution of BAs to the pathogenesis of latent autoimmune diabetes in adults (LADA) remains unclear. This study was aimed at investigating the association of serum BAs with different diabetes types and analyzing its correlation with main clinical and laboratory parameters.

METHODS

Patients with LADA, patients with T2D, and healthy controls (HCs) were enrolled. Serum BA profiles and inflammatory cytokines were measured. The correlation of BA species with different indicators was assessed by Spearman's correlation method.

RESULTS

Patients with diabetes (LADA and T2D) had significantly higher serum BAs, especially conjugated BAs, compared with those in HCs. Nevertheless, serum BA profiles had no special role in the progression of LADA, because no significant differences in BAs were observed between LADA and T2D patients. Interestingly, HbA1c levels and HOMA-β were found to be correlated with a series of BA species. Proinflammatory cytokines (IL-1β, IL-6, and TNF-α) and anti-inflammatory cytokine (IL-10) were all positively associated with several BA species, especially the conjugated secondary BAs.

CONCLUSION

Serum BAs regulate glucose homeostasis, but have no special value in the pathogenesis of LADA patients. Our study adds further information about the potential value of serum BAs in different types of diabetes.

Analysis of detrended fluctuation function derived from continuous glucose monitoring may assist in distinguishing latent autoimmune diabetes in adults from T2DM

BACKGROUND

We aimed to explore the performance of detrended fluctuation function (DFF) in distinguishing patients with latent autoimmune diabetes in adults (LADA) from type 2 diabetes mellitus (T2DM) with glucose data derived from continuous glucose monitoring.

METHODS

In total, 71 LADA and 152 T2DM patients were enrolled. Correlations between glucose parameters including time in range (TIR), mean glucose, standard deviation (SD), mean amplitude of glucose excursions (MAGE), coefficient of variation (CV), DFF and fasting and 2-hour postprandial C-peptide (FCP, 2hCP) were analyzed and compared. Receiver operating characteristics curve (ROC) analysis and 10-fold cross-validation were employed to explore and validate the performance of DFF in diabetes classification respectively.

RESULTS

Patients with LADA had a higher mean glucose, lower TIR, greater SD, MAGE and CV than those of T2DM (P<0.001). DFF achieved the strongest correlation with FCP (r = -0.705, P<0.001) as compared with TIR (r = 0.485, P<0.001), mean glucose (r = -0.337, P<0.001), SD (r = -0.645, P<0.001), MAGE (r = -0.663, P<0.001) and CV (r = -0.639, P<0.001). ROC analysis showed that DFF yielded the greatest area under the curve (AUC) of 0.862 (sensitivity: 71.2%, specificity: 84.9%) in differentiating LADA from T2DM as compared with TIR, mean glucose, SD, MAGE and CV (AUC: 0.722, 0.650, 0.800, 0.820 and 0.807, sensitivity: 71.8%, 47.9%, 63.6%, 72.7% and 78.8%, specificity: 67.8%, 83.6%, 80.9%, 80.3% and 72.4%, respectively). The kappa test indicated a good consistency between DFF and the actual diagnosis (kappa = 0.551, P<0.001). Ten-fold cross-validation showed a stable performance of DFF with a mean AUC of 0.863 (sensitivity: 78.8%, specificity: 77.8%) in 10 training sets and a mean AUC of 0.866 (sensitivity: 80.9%, specificity: 84.1%) in 10 test sets.

CONCLUSIONS

A more violent glucose fluctuation pattern was marked in patients with LADA than T2DM. We first proposed the possible role of DFF in distinguishing patients with LADA from T2DM in our study population, which may assist in diabetes classification.

Characteristics of the Gut Microbiota and Metabolism in Patients With Latent Autoimmune Diabetes in Adults: A Case-Control Study

OBJECTIVE

Type 1 and type 2 diabetes are associated with gut dysbiosis. However, the relationship between the gut microbiota and latent autoimmune diabetes in adults (LADA), sharing clinical and metabolic features with classic type 1 and type 2 diabetes, remains unclear. Here, we used a multiomics approach to identify the characteristics of the gut microbiota and metabolic profiles in patients with LADA.

RESEARCH DESIGN AND METHODS

This age- and sex-matched case-control study included 30 patients with LADA, 31 patients with classic type 1 diabetes, 30 patients with type 2 diabetes, and 29 healthy individuals. The gut microbiota profiles were identified through the 16S rRNA gene, and fecal and serum metabolites were measured through untargeted liquid chromatography-mass spectrometry.

RESULTS

Patients with LADA had a significantly different structure and composition of the gut microbiota and their metabolites as well as a severe deficiency of short-chain fatty acid-producing bacteria. The gut microbiota structure of the patients with LADA was more similar to that of patients with type 1 diabetes who were positive for GAD antibody. We identified seven serum metabolite modules and eight fecal metabolite modules that differed between the LADA group and the other groups.

CONCLUSIONS

The characteristic gut microbiota and related metabolites of patients with LADA are associated with autoantibodies, glucose metabolism, islet function, and inflammatory factors, which may contribute to the pathogenesis of LADA. Future longitudinal studies should explore whether modulating the gut microbiota and related metabolites can alter the natural course of autoimmune diabetes in the quest for new therapeutics.

The Association of CTLA-4 rs231775 and rs3087243 Polymorphisms with Latent Autoimmune Diabetes in Adults: A Meta-Analysis

Polymorphisms rs231775 and rs3087243 of cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) gene have been associated with risk of latent autoimmune diabetes in adults (LADA). However, the results were inconsistent. The purpose of this study was to quantitatively assess the relationship between polymorphisms rs231775 and rs3087243 of CTLA-4 and LADA in a larger pooled population by performing a meta-analysis. Systematic search for eligible studies was conducted in PubMed, Web of Science, and Embase. Case-control studies containing genotype frequencies of polymorphisms rs231775 or rs3087243 were selected, and pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the associations between polymorphisms of CTLA-4 and LADA in allelic, dominant and recessive genetic model. A total of eleven studies, in which five studies reported rs231775, two studies reported rs3087342, and four studies reported both rs231775 and rs3087243, were identified. Among them, one study wasn't included in the following meta-analysis because the distribution of genotypes in the control group didn't comply with Hardy-Weinberg equilibrium. Significant associations with susceptibility to LADA were detected for rs231775 (785 cases and 3435 controls) and for rs3087243 (820 cases and 4824 controls) in overall population. Further subgroup analyses for ethnicity (Asian, Caucasian, and African) have also indicated the positive association between rs231775 and LADA. As for rs3087243, subgroup analyses detected the association between polymorphism and LADA in Caucasian population under recessive model. Polymorphisms rs231775 and rs3087243 of CTLA-4 gene are potential risk factors for LADA and may serve as novel genetic biomarkers of 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.

Adult-Onset Type 1 Diabetes: Current Understanding and Challenges

Recent epidemiological data have shown that more than half of all new cases of type 1 diabetes occur in adults. Key genetic, immune, and metabolic differences exist between adult- and childhood-onset type 1 diabetes, many of which are not well understood. A substantial risk of misclassification of diabetes type can result. Notably, some adults with type 1 diabetes may not require insulin at diagnosis, their clinical disease can masquerade as type 2 diabetes, and the consequent misclassification may result in inappropriate treatment. In response to this important issue, JDRF convened a workshop of international experts in November 2019. Here, we summarize the current understanding and unanswered questions in the field based on those discussions, highlighting epidemiology and immunogenetic and metabolic characteristics of adult-onset type 1 diabetes as well as disease-associated comorbidities and psychosocial challenges. In adult-onset, as compared with childhood-onset, type 1 diabetes, HLA-associated risk is lower, with more protective genotypes and lower genetic risk scores; multiple diabetes-associated autoantibodies are decreased, though GADA remains dominant. Before diagnosis, those with autoantibodies progress more slowly, and at diagnosis, serum C-peptide is higher in adults than children, with ketoacidosis being less frequent. Tools to distinguish types of diabetes are discussed, including body phenotype, clinical course, family history, autoantibodies, comorbidities, and C-peptide. By providing this perspective, we aim to improve the management of adults presenting with type 1 diabetes.

Adult-onset autoimmune diabetes identified by glutamic acid decarboxylase autoantibodies: a retrospective cohort study

AIMS/HYPOTHESIS

Patients with GAD antibodies (GADAb) showing clinical features of type 2 diabetes typically exhibit progression to an insulin-dependent state in several months or years. This condition is diagnosed as slowly progressive insulin-dependent (type 1) diabetes mellitus (SPIDDM) or latent autoimmune diabetes in adults, a subtype of adult-onset autoimmune diabetes. However, some patients diagnosed with adult-onset autoimmune diabetes do not progress to an insulin-dependent state. We conducted a retrospective cohort study to identify patients with non-insulin-dependent diabetes among those diagnosed with adult-onset autoimmune diabetes using measurable indicators in routine clinical practice.

METHODS

We surveyed data from the electronic medical records of all patients with GADAb from eight medical centres in Japan for selecting and analysing patients who matched the diagnostic criteria of SPIDDM.

RESULTS

Overall, 345 patients were analysed; of these, 162 initiated insulin therapy (insulin therapy group), whereas 183 did not (non-insulin therapy group) during the follow-up period (median 3.0 years). Patients in the non-insulin therapy group were more likely to be male and presented a later diabetes onset, shorter duration of diabetes, higher BMI, higher blood pressure levels, lower HbA_1c levels, lower GADAb levels and lesser antidiabetic agent use than those in the insulin therapy group when GADAb was first identified as positive. A Cox proportional hazards model showed that BMI, HbA_1c levels and GADAb levels were independent factors for progression to insulin therapy. Kaplan-Meier analyses revealed that 86.0% of the patients with diabetes having GADAb who presented all three factors (BMI ≥ 22 kg/m², HbA_1c < 75 mmol/mol [9.0%] and GADAb <10.0 U/ml) did not require insulin therapy for 4 years.

CONCLUSIONS/INTERPRETATION

Higher BMI (≥22 kg/m²), lower HbA_1c (<75 mmol/mol [9.0%]) and lower GADAb levels (<10.0 U/ml) can predict a non-insulin-dependent state for at least several years in Japanese patients with diabetes having GADAb.

Increased spontaneous CCL2 (MCP-1) and CCL5 (RANTES) secretion in vitro in LADA compared to type 1 diabetes and type 2 diabetes: Action LADA 14

AIMS

Immune-mediated type 1 diabetes (T1D) in adulthood and latent autoimmune diabetes in adults (LADA) share similar pathological mechanisms but differ clinically in disease progression. The aim of this study was to acquire insights into spontaneous and stimulated chemokine secretion of immune cells in different diabetes types.

MATERIALS AND METHODS

We investigated in vitro spontaneous, mitogen (PI) and antigen (HSP60, p277, pGAD, pIA2) stimulated chemokine secretion of leucocytes from patients with T1D (n = 32), LADA (n = 22), type 2 diabetes (T2D; n = 49), and glucose-tolerant individuals (n = 13). Chemokine concentration in supernatants was measured for CCL2 (MCP-1), CXCL10 (IP10) and CCL5 (RANTES) using a multiplex bead array assay.

RESULTS

Spontaneous secretion of CCL2 and CCL5 were higher in LADA compared to T1D and T2D (all p < 0.05) while CXCL10 was similar in the groups. Mitogen-stimulated secretion of CCL2 in LADA was lower compared to T1D and T2D (all p < 0.05) while CXCL10 and CCL5 were similar in all groups. Upon stimulation with pIA2 the secretion of CCL2 in LADA was lower compared to T2D (p < 0.05). Spontaneous CXCL10 secretion in LADA was positively associated with body mass index (r²  = 0.35; p = 0.0035) and C-peptide (r²  = 0.30; p = 0.009).

CONCLUSIONS

Chemokine secretion is altered between different diabetes types. Increased spontaneous secretion of CCL2 and CCL5 and decreased secretion of CCL2, upon stimulation with PI and pIA2, in LADA compared to T1D and T2D could reflect altered immune responsiveness in LADA patients in association with their slower clinical progression compared to insulin dependence.

Improving clinical utility of GAD65 autoantibodies by electrochemiluminescence assay and clinical phenotype when identifying autoimmune adult-onset diabetes

AIMS/HYPOTHESIS

It is important to differentiate the two major phenotypes of adult-onset diabetes, autoimmune type 1 diabetes and non-autoimmune type 2 diabetes, especially as type 1 diabetes presents in adulthood. Serum GAD65 autoantibodies (GADA) are the most sensitive biomarker for adult-onset autoimmune type 1 diabetes, but the clinical value of GADA by current standard radiobinding assays (RBA) remains questionable. The present study focused on the clinical utility of GADA differentiated by a new electrochemiluminescence (ECL) assay in patients with adult-onset diabetes.

METHODS

Two cohorts were analysed including 771 diabetic participants, 30-70 years old, from the Action LADA study (n = 6156), and 2063 diabetic participants, 20-45 years old, from the Diabetes in Young Adults (DiYA) study. Clinical characteristics of participants, including requirement of early insulin treatment, BMI and development of multiple islet autoantibodies, were analysed according to the status of RBA-GADA and ECL-GADA, respectively, and compared between these two assays.

RESULTS

GADA was the most prevalent and predominant autoantibody, >90% in both cohorts. GADA positivity by either RBA or ECL assay significantly discriminated clinical type 1 from type 2 diabetes. However, in both cohorts, participants with ECL-GADA positivity were more likely to require early insulin treatment, have multiple islet autoantibodies, and be less overweight (for all p < 0.0001). However, clinical phenotype, age at diagnosis and BMI independently improved positive predictive value (PPV) for the requirement of insulin treatment, even augmenting ECL-GADA. Participants with GADA detectable by RBA, but not confirmed by ECL, had a phenotype more similar to type 2 diabetes. These RBA-GADA positive individuals had lower affinity GADA compared with participants in which GADA was confirmed by ECL assay.

CONCLUSIONS/INTERPRETATION

Detection of GADA by ECL assay, given technical advantages over RBA-GADA, identified adult-onset diabetes patients at higher risk of requiring early insulin treatment, as did clinical phenotype, together allowing for more accurate clinical diagnosis and management.

The role of autoimmunity in the pathophysiology of type 2 diabetes: Looking at the other side of the moon

Efforts to unravel the pathophysiological mechanisms of type 2 diabetes (T2D) have been traditionally trapped into a metabolic perspective. However, T2D is a phenotypically and pathophysiologically heterogenous disorder, and the need for a tailored approach in its management is becoming increasingly evident. There is emerging evidence that irregular immune responses contribute to the development of hyperglycemia in T2D and, inversely, that insulin resistance is a component of the pathogenesis of autoimmune diabetes. Nevertheless, it has not yet been fully elucidated to what extent the presence of conventional autoimmune markers, such as autoantibodies, in subjects with T2D might affect the natural history of the disease and particularly each response to various treatments. The challenge for future research in the field is the discovery of novel genetic, molecular, or phenotypical indicators that would enable the characterization of specific subpopulations of people with T2D who would benefit most from the addition of immunomodulatory therapies to standard glucose-lowering treatment. This narrative review aims to discuss the plausible mechanisms through which the immune system might be implicated in the development of metabolic disturbances in T2D and obesity and explore a potential role of immunotherapy in the future management of the disorder and its complications.

Uncommon forms of diabetes

Diabetes mellitus is a common condition which all clinicians will encounter in their clinical practice. The most common form is type 2 diabetes followed by type 1 diabetes. However, there are many other atypical forms of diabetes which are important for a clinician to consider as it can impact on the diagnosis and their management.This article focuses on maturity onset diabetes of the young (MODY), latent autoimmune diabetes in adults (LADA), ketosis-prone diabetes and other secondary forms of diabetes such as pancreatic cancer and haemochromatosis. We briefly describe the key clinical features of these forms of diabetes and their investigations and treatment.

Latent Autoimmune Diabetes of Adults (LADA) Is Likely to Represent a Mixed Population of Autoimmune (Type 1) and Nonautoimmune (Type 2) Diabetes

Latent autoimmune diabetes of adults (LADA) is typically defined as a new diabetes diagnosis after 35 years of age, presenting with clinical features of type 2 diabetes, in whom a type 1 diabetes-associated islet autoantibody is detected. Identifying autoimmune diabetes is important since the prognosis and optimal therapy differ. However, the existing LADA definition identifies a group with clinical and genetic features intermediate between typical type 1 and type 2 diabetes. It is unclear whether this is due to 1) true autoimmune diabetes with a milder phenotype at older onset ages that initially appears similar to type 2 diabetes but later requires insulin, 2) a disease syndrome where the pathophysiologies of type 1 and type 2 diabetes are both present in each patient, or 3) a heterogeneous group resulting from difficulties in classification. Herein, we suggest that difficulties in classification are a major component resulting from defining LADA using a diagnostic test-islet autoantibody measurement-with imperfect specificity applied in low-prevalence populations. This yields a heterogeneous group of true positives (autoimmune type 1 diabetes) and false positives (nonautoimmune type 2 diabetes). For clinicians, this means that islet autoantibody testing should not be undertaken in patients who do not have clinical features suggestive of autoimmune diabetes: in an adult without clinical features of type 1 diabetes, it is likely that a single positive antibody will represent a false-positive result. This is in contrast to patients with features suggestive of type 1 diabetes, where false-positive results will be rare. For researchers, this means that current definitions of LADA are not appropriate for the study of autoimmune diabetes in later life. Approaches that increase test specificity, or prior likelihood of autoimmune diabetes, are needed to avoid inclusion of participants who have nonautoimmune (type 2) diabetes. Improved classification will allow improved assignment of prognosis and therapy as well as an improved cohort in which to analyze and better understand the detailed pathophysiological components acting at onset and during disease progression in late-onset autoimmune diabetes.