Worse glycaemic control in LADA patients than in those with type 2 diabetes, despite a longer time on insulin therapy

Pathology of Diabetes-Induced Immune Dysfunction

Diabetes is associated with numerous comorbidities, one of which is increased vulnerability to infections. This review will focus on how diabetes mellitus (DM) affects the immune system and its various components, leading to the impaired proliferation of immune cells and the induction of senescence. We will explore how the pathology of diabetes-induced immune dysfunction may have similarities to the pathways of "inflammaging", a persistent low-grade inflammation common in the elderly. Inflammaging may increase the likelihood of conditions such as rheumatoid arthritis (RA) and periodontitis at a younger age. Diabetes affects bone marrow composition and cellular senescence, and in combination with advanced age also affects lymphopoiesis by increasing myeloid differentiation and reducing lymphoid differentiation. Consequently, this leads to a reduced immune system response in both the innate and adaptive phases, resulting in higher infection rates, reduced vaccine response, and increased immune cells' senescence in diabetics. We will also explore how some diabetes drugs induce immune senescence despite their benefits on glycemic control.

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

AIMS

To test, for the first time in latent autoimmune diabetes in adults (LADA), the effects of autoantigen-specific immunotherapy by intralymphatic administration of aluminium-formulated recombinant human glutamic acid decarboxylase 65 (GAD-alum); specifically, to test if this treatment is safe, to test whether it induces a strong immunological response akin to a similar protocol in type 1 diabetes and to look for associations with preserved beta-cell function.

MATERIALS AND METHODS

Three GAD-alum injections, 4 μg each, were administered 1 month apart into an inguinal lymph node in 14 people with newly diagnosed LADA (age 30-62 years) presenting with high levels of antibodies against glutamic acid decarboxylase (GADA). Adverse effects, immunological variables and beta-cell function were monitored, with detailed measurements at 5 and 12 months from baseline.

RESULTS

Clinical adverse effects were minor and transient and measured laboratory variables were unaffected. All participants completed the study. Treatment raised levels of GADA, elicited strong effects on reactivity of peripheral blood mononuclear cells to GAD and raised cytokine/chemokine levels. Beta-cell function appeared stable preferentially in the seven participants carrying human leukocyte antigen (HLA) haplotypes DR3DQ2, as assessed by C-peptide glucagon tests (P < 0.05 vs. seven non-carriers).

CONCLUSION

Intralymphatic treatment with GAD-alum in LADA is without clinical or other safety concerns over a 12-month period. As in a similar protocol used in type 1 diabetes, treatment exerts a strong immunological impact and is compatible with protection of beta-cell function preferentially in HLA-DR3DQ2 LADA patients. These findings pave the way for a randomized controlled trial in this important subgroup of LADA patients.

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.

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.

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.

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.

Oxidative Stress and Its Related Factors in Latent Autoimmune Diabetes in Adults

AIMS

Few research was reported to explore oxidative stress in individuals with latent autoimmune diabetes in adults (LADA). Therefore, our goal is to study oxidative stress and related factors in LADA patients.

METHODS

In this study, 250 Chinese inpatients were diagnosed with LADA (n = 110) and type 2 diabetes mellitus (n = 140) and 140 healthy volunteers were recruited. Moreover, individuals with LADA were followed for 6 months to evaluate whether short-term glycemic control during hospitalization can improve oxidative stress. Clinical and laboratory measurements of height, weight, blood pressure, glycosylated hemoglobin (HbA1c), blood lipids, 8-isoprostaglandin F2α (8-iso-PGF2α), and superoxide dismutase (SOD) were performed. Stepwise multiple regression analyses were used to assess factors that related to oxidative stress in individuals with LADA.

RESULTS

Compared with patients with type 2 diabetes, individuals with LADA have better oxidative stress and worse oxidative stress than healthy volunteers. After multiple regression analyses, systolic blood pressure, HbA1c, duration of diabetes, and diabetic retinopathy were associated with 8-iso-PGF2α and HbA1c. Diabetic retinopathy and diabetic ketosis were associated with SOD in individuals with LADA. Our results also revealed that, after 6 months of follow-up, oxidative stress was improved to some extent in persons with LADA.

CONCLUSIONS

Our results show that compared with type 2 diabetes, LADA means less oxidative stress, and compared with healthy volunteers, it means more oxidative stress. Systolic blood pressure, HbA1c, duration of diabetes, diabetic retinopathy, and ketosis were associated with oxidative stress in individuals with LADA. Furthermore, short-term glycemic control can improve oxidative stress to some extent in individuals with LADA.

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

Objective

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

Methods

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

Results

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

Conclusion

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

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.

Geographic location determines beta-cell autoimmunity among adult Ghanaians: Findings from the RODAM study

Introduction

Beta‐cell autoantibodies are established markers of autoimmunity, which we compared between Ghanaian adults with or without diabetes, living in rural and urban Ghana and in three European cities.

Methods

In the multicenter cross‐sectional Research on Obesity and Diabetes among African Migrants (RODAM) study (N = 5898), we quantified autoantibodies against glutamic acid decarboxylase (GAD65Ab) by radioligand binding assay (RBA) and established cut‐offs for positivity by displacement analysis. In a subsample, we performed RBA for zinc transporter‐8 autoantibodies (ZnT8Ab). Associations of environmental, sociodemographic, and clinical factors with GAD65Ab were calculated.

Results

In this study population (age: 46.1 ± 11.9 years; female: 62%; Ghana‐rural: 1111; Ghana‐urban: 1455; Europe: 3332), 9.2% had diabetes with adult‐onset. GAD65Ab concentrations were the highest in Ghana‐rural (32.4; 10.8‐71.3 U/mL), followed by Ghana‐urban (26.0; 12.3‐49.1 U/mL) and Europe (11.9; 3.0‐22.8 U/mL) with no differences between European cities. These distributions were similar for ZnT8Ab. Current fever, history of fever, and higher concentrations of liver enzymes marginally explained site‐specific GAD65Ab concentrations. GAD65Ab positivity was as frequent in diabetes as in nondiabetes (5.4% vs 6.1%; P = .25). This was also true for ZnT8Ab positivity.

Conclusion

Geographic location determines the occurrence of GAD65Ab and ZnT8Ab more than the diabetes status. Beta‐cell autoimmunity may not be feasible to differentiate diabetes subgroups in this population.

Standard mortality rates and years of life lost for serologically defined adult-onset type 1 and type 2 diabetes - A fifteen year follow-up

AIMS

The Diabetes Incidence in Kronoberg (DIK) study of adult-onset diabetes used serological classification. Standard Mortality Rates (SMR) and Years of Life Lost (YLL) 15 years after adult-onset (18-100 years) of diabetes were compared to the population of Kronoberg.

METHODS

Of 1609/1660 (97%) patients, 112 (7%) had type 1 (T1D) (GADA⁺ and/or ICA⁺, and/or C-peptide < 0.25 nmol/l), and 1497 (93%) had type 2 diabetes (T2D) (antibody^- and C-peptide ≥ 0.25 nmol/l). The National Swedish Mortality Register provided time of death.

RESULTS

For T1D SMR did not differ from the Kronoberg population in any age group. In T2D SMR was 1.20 (1.12-1.29). After 15 years 26% (29/112) T1D and 52% (785/1497) T2D patients had died, p < 0.0001. In T2D SMR was 5.6 (30-39 years), 2 (40-59 years), 1.4 (60-69 years), and thereafter no difference. There were no significant sex differences in mortality, and no YLL to adult-onset T1D, but five YLL to T2D for onset at ages 20-60 years.

CONCLUSIONS

For adult-onset T1D SMR did not differ from the general population, in contrast to previous findings in childhood-onset (< 30 years of age) T1D. The difference in mortality between persons with diabetes and the general population was due to higher mortality in T2D.

Uncommon Presentations of Diabetes: Zebras in the Herd

The majority of patients with diabetes are diagnosed as having either type 1 or type 2 diabetes. However, when encountered in clinical practice, some patients may not match the classic diagnostic criteria or expected clinical presentation for either type of the disease. Latent autoimmune, ketosis-prone, and monogenic diabetes are nonclassical forms of diabetes that are often misdiagnosed as either type 1 or type 2 diabetes. Recognizing the distinguishing clinical characteristics and understanding the diagnostic criteria for each will lead to appropriate treatment, facilitate personalized medicine, and improve patient outcomes.

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.

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

AIMS

To compare outcomes of glucagon-stimulated C-peptide tests (GSCTs) in people with latent autoimmune diabetes in adults (LADA) after a 21-month intervention with either insulin or the dipeptidyl peptidase-4 inhibitor sitagliptin.

RESEARCH DESIGN AND METHODS

We included 64 glutamic acid decarboxylase (GAD) antibody-positive individuals, who were diagnosed with diabetes <3 years before the study, aged 30 to 70 years, and without clinical need for insulin treatment. We stratified participants by age and body mass index (BMI) and evaluated β-cell function by GSCT after a 48-hour temporary withdrawal of study medication.

RESULTS

Age at randomization (mean 53 years), BMI (mean 27 kg/m² ) and metabolic markers were similar between treatment arms. Glycated haemoglobin concentrations during intervention did not differ between arms. Fasting C-peptide concentrations after the intervention were similar, as were stimulated C-peptide levels (0.82 ± 0.63 nmol/L after insulin, 0.82 ± 0.46 nmol/L after sitagliptin; nonsignificant). Autoimmunity in the study population (estimated from GAD antibody titres and positivity/no positivity for zinc transporter 8 and islet antigen 2 antibodies) affected the evolution of the GSCT results significantly, which deteriorated in participants with high but not in those with low autoimmunity. Adjustment using analysis of covariance for the degree of autoimmunity did not alter the findings of no difference between treatment arms.

CONCLUSIONS

β-cell function after intervention was similar in patients with insulin- and sitagliptin-treated LADA, regardless of the strength of autoimmunity. Further, participants with low levels of GAD antibodies did not experience progressive deterioration of β-cell function over a 21-month period. Taken together, these findings could be useful for clinicians' choices of treatment in people with LADA.

Latent autoimmune diabetes of adulthood (LADA) is associated with small fibre neuropathy

AIM

To assess if latent autoimmune diabetes of adulthood (LADA) is associated with small fibre neuropathy.

METHODS

Participants with LADA (n=31), Type 2 diabetes (n=31) and healthy control participants without diabetes (n=31) underwent a detailed assessment of neurologic deficits, quantitative sensory testing, electrophysiology, skin biopsy and corneal confocal microscopy.

RESULTS

The groups were matched for age (healthy control without diabetes: 53.5±9.1 vs. Type 2 diabetes: 58.0±6.5 vs. LADA: 53.2±11.6 years), duration of diabetes (Type 2 diabetes: 10.0±8.3 vs. LADA: 11.0±9.1 years) and blood pressure. However, BMI (P=0.01) and triglycerides (P=0.0008) were lower and HbA_1c (P=0.0005), total cholesterol (P=0.01) and HDL (P=0.002) were higher in participants with LADA compared with Type 2 diabetes. Peroneal motor nerve conduction velocity (P=0.04) and sural sensory nerve conduction velocity (P=0.008) were lower in participants with latent autoimmune diabetes in adults compared with Type 2 diabetes. Intra-epidermal nerve fibre density (P=0.008), corneal nerve fibre density (P=0.003) and corneal nerve branch density (P=0.006) were significantly lower in participants with LADA compared with Type 2 diabetes. There were no significant differences in the other neuropathy parameters.

CONCLUSIONS

Despite comparable age and duration of diabetes, participants with LADA demonstrate more severe neuropathy and particularly small fibre neuropathy, compared with participants with Type 2 diabetes.

Immunological and clinical characteristics of latent autoimmune diabetes in the elderly

BACKGROUND

Latent autoimmune diabetes in adults (LADA) is determined by both a noninsulin-dependent clinical presentation and an autoimmune pathogenic process. Glutamic acid decarboxylase antibody (GADA) constitutes the most important marker, although IA-2A and ZnT8A also define LADA presentation. Type 2 diabetes mellitus (T2DM) is the most prevalent type particularly over 65 years old. Studies about autoimmunity in this age group are scarce.

OBJECTIVE

The aim of this work was to determine whether three autoantibodies for diabetes autoimmunity were present in elderly T2DM patients, and to assess the distinctive clinical features of autoantibody-positive patients.

RESEARCH DESIGN AND METHODS

We recruited 153 patients with diabetes with onset of diabetes after 65 years of age and a BMI under 30 kg/m² .

RESULTS

The prevalence of at least one of the autoantibodies was 15.68% (24/153). The most prevalent autoantibody was GADA with 8.49% (13/153), followed by ZnT8A with 6.50% (10/153) and IA2A with 1.96% (3/153). The autoimmunity-positive group presented higher HbA1c (7.01 ± 1.98 vs 6.35 ± 1.01; P = 0.007) and more prevalent insulin therapy (25% vs 10.85%; P = 0.047). GADA-positive patients with diabetes presented higher FPG (7.79 ± 3.79 mmol/L vs 6.43 ± 1.6 mmol/L; P = 0.014) and insulin therapy more frequently (46% vs 10.71%; p = 0.015). GADA titre levels in the individuals with BMI under 27 kg/m² were higher (35.00 ± 4.20) than those in the group with BMI over 27 kg/m² (8.83 ± 3.041; P = 0.0005).

CONCLUSION

Autoantibodies GADA and Znt8A may be useful markers in identifying a subgroup of older patients with a clinical presentation of diabetes which could be characterized as latent autoimmune diabetes in the elderly.

Islet autoantibody positivity in overweight and obese adults with type 2 diabetes

Islet autoantibodies are typically associated with type 1 diabetes, but have been found in patients diagnosed with type 2 diabetes in whom they are associated with lower adiposity. The significance of autoantibody positivity in overweight and obese patients is not well understood. The aim of this study was to determine the prevalence and clinical significance of islet autoantibodies in overweight/obese adults diagnosed with type 2 diabetes. This study includes 204 participants at one site of the multicenter Look AHEAD (Action for Health in Diabetes) trial (ClinicalTrials.gov identifier: NCT00017953) which randomized overweight/obese adults diagnosed with type 2 diabetes to an intensive lifestyle intervention or diabetes support and education. We measured antibodies to glutamic acid decarboxylase, insulinoma antigen-2, and zinc transporter 8. Participants with and without autoantibodies were compared with respect to baseline clinical features, and longitudinal changes in weight, hemoglobin A1c, and antihyperglycemic medications. We found that 13 participants (6.4%) were autoantibody positive, including six of 47 participants (12.8%) with BMI ≥40 kg/m². At baseline, autoantibody positive participants had higher HDL cholesterol (1.27 vs. 1.09 mmol/L, p = .034) and lower fasting C-peptide (0.32 vs. 0.57 nmol/L, p = .049). Over four years, autoantibody positive participants lost 5.1 kg more weight than autoantibody negative participants (p = .056). Longitudinal changes in hemoglobin A1c did not differ by autoantibody status, though autoantibody positive participants were more likely to increase the number of antihyperglycemic medications or initiate insulin (p = .011). In conclusion, islet autoantibodies were present in 6.4% of overweight/obese adults with type 2 diabetes including those with severe obesity, and were associated with distinct clinical features. The effect of autoantibody positivity on weight loss interventions requires further study.

Urinary C-Peptide Creatinine Ratio as a Non-Invasive Tool for Identifying Latent Autoimmune Diabetes in Adults (LADA)

PURPOSE

Latent autoimmune diabetes in adults (LADA) is a slowly progressing form of immune-mediated diabetes that combines phenotypical features of both type 2 diabetes mellitus (T2DM) and type 1 diabetes mellitus (T1DM), meaning that accurate and early diagnosis of this subtype of diabetes is critical for optimal long-term management. Urinary C-peptide creatinine ratio (UCPCR) represents a non-invasive and practical method for assessing endogenous insulin production to facilitate diabetes classification. However, no study to date has reported the use of UCPCR in identifying LADA.

PATIENTS AND METHODS

A total of 574 subjects were included in our study (42 LADA, 61 T1DM, 471 T2DM). All participants were evaluated for UCPCR and underwent clinical and laboratory evaluations. UCPCR was compared among different subtypes of diabetes using multinomial regression analysis, and a receiver operating characteristic (ROC) curve was used to identify its performance in diagnosing LADA.

RESULTS

UCPCR was lower in LADA (0.4±0.6 nmol/mmol) compared with T2DM (1.2±0.9 nmol/mmol), but higher than in T1DM (0.2±0.3 nmol/mmol) (p<0.05). The association between UCPCR and LADA remained significant after adjusting for gender, age, age at diagnosis, body mass index, high-density lipoprotein cholesterol, and triglyceride (OR, 95% confidence interval (CI), 0.29 (0.09, 0.95)). The ROC curve revealed an area under the curve of 0.835 (95% CI (0.742-0.928), p<0.001). The cut-off point for UCPCR ≤ 0.46 nmol/mmol was 82.1% for sensitivity and 76.7% for specificity in the diagnosis of LADA.

CONCLUSION

UCPCR may represent a non-invasive, simple, and practical measurement of insulin secretion for early discrimination of LADA in routine clinical practice.

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

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

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.

Dulaglutide treatment results in effective glycaemic control in latent autoimmune diabetes in adults (LADA): A post-hoc analysis of the AWARD-2, -4 and -5 Trials

AIMS

Patients with a type-2-diabetes (T2D) phenotype positive for glutamic acid decarboxylase antibodies (GADA) represent the majority of cases of latent autoimmune diabetes of the adult (LADA). The GLP-1 receptor agonist dulaglutide, recently introduced for treatment of T2D, has yet to be evaluated in LADA patients. Our primary objective was to evaluate the effect of dulaglutide on glycaemic control (HbA1c) in GADA-positive LADA vs GADA-negative T2D patients.

METHODS

A post-hoc analysis was performed using data from 3 randomized phase 3 trials (AWARD-2,-4,-5; patients with GADA assessment) which were part of the dulaglutide clinical development programme in T2D. LADA patients were identified by GADA ≥5 IU/mL (ELISA). Changes in HbA1c during 12 months of treatment with dulaglutide or comparator were analysed using mixed-effect model repeated measures.

RESULTS

Of 2466 adults tested for GADA (dulaglutide, 1710; glargine, 298; sitagliptin, 294; placebo, 164), 2278 (92.4%) were GADA-negative and 188 (7.6%) were GADA-positive, including 58 GADA-high patients (> 200 IU/mL) and 130 GADA-low patients (≤200 and ≥5 IU/mL). Overall, baseline parameters were comparable between the groups. Dulaglutide resulted in comparable HbA1c reductions in GADA-negative (LS mean change [95%CI], -1.09% [-1.15, -1.03]) and GADA-positive patients (-0.94% [-1.15, -0.72]) at 12 months. HbA1c reductions were numerically, but not statistically, significantly larger in GADA-low patients (-1.02% [-1.26, -0.78]) vs GADA-high patients (-0.72% [-1.21,-0.24]) at 12 months. Similar outcomes were observed at 3 and 6 months.

CONCLUSIONS

These data are the first to indicate that dulaglutide was effective in reducing HbA1c in LADA patients.

Islet Cell Associated Autoantibodies and C-Peptide Levels in Patients with Diabetes and Symptoms of Gastroparesis

INTRODUCTION

Individuals with diabetes are at increased risk for complications, including gastroparesis. Type 1 diabetes mellitus (T1DM) is an autoimmune disorder resulting in decreased beta-cell function. Glutamic acid decarboxylase-65 antibody (GADA) is the most commonly used test to assess autoimmunity while C-peptide level is used to assess beta-cell function. Patients with type 2 diabetes mellitus (T2DM), who are GADA positive, are labeled latent autoimmune diabetes in adults (LADA).

OBJECTIVE

To characterize patients with T1 and T2DM who have symptoms of gastroparesis using GADA and C-peptide levels and to look for association with the presence of gastroparesis and its symptom severity.

DESIGN

113 T1DM and 90 T2DM patients with symptoms suggestive of gastroparesis were studied. Symptom severity was assessed using Gastroparesis Cardinal Symptom Index (GCSI). Serum samples were analyzed for GADA and C-peptide.

RESULTS

Delayed gastric emptying was present in 91 (81%) of T1DM and 60 (67%) of T2DM patients (p = 0.04). GADA was present in 13% of T2DM subjects [10% in delayed gastric emptying and 20% in normal gastric emptying (p = 0.2)]. Gastric retention and GCSI scores were mostly similar in GADA positive and negative T2DM patients. GADA was present in 45% of T1DM subjects [46% in delayed gastric emptying and 41% in normal gastric emptying (p = 0.81)]. Low C-peptide levels were seen in 79% T1DM patients and 8% T2DM. All seven T2DM patients with low C-peptide were taking insulin compared to 52% of T2DM with normal C-peptide.

CONCLUSION

GADA was present in 13% while low C-peptide was seen in 8% of our T2DM patients with symptoms of gastroparesis. Neither did correlate with degree of delayed gastric emptying or symptom severity.

CLINICALTRIALSGOV IDENTIFIER

NCT01696747.

Metabolic risk profiles in diabetes stratified according to age at onset, islet autoimmunity and fasting C-peptide

OBJECTIVE

Islet autoimmunity, age at onset and time to insulin treatment are often used to define subgroups of diabetes. However, the latter criterion is not clinical useful. Here, we examined whether an unbiased stratification of diabetes according to age at onset, fasting C-peptide and GAD autoantibodies (GADab) defines groups with differences in glycaemic control and markers of cardiometabolic risk.

DESIGN AND METHODS

A cohort of 4374 adults with relatively newly diagnosed diabetes referred to a Danish hospital during 1997-2012 was stratified according to age at onset above or below 30 years, fasting C-peptide above or below 300 pmol/l (CPEP_high or CPEP_low), and presence or absence of GADab (GAD_pos or GAD_neg). HbA_1c, BMI, blood pressure (BP), lipid profile, alanine aminotransferase (ALT) and creatinine were evaluated.

RESULTS

GADab were present in 13% of the cohort. Age at onset was not associated with major differences between groups. Patients with insulin deficient diabetes (CPEP_low; n = 503) had higher HbA_1c but otherwise lower cardiometabolic risk (lower BMI, BP, LDL, triacylglycerol, and ALT, and higher HDL) than both patients with latent autoimmune diabetes of adults (LADA defined as GAD_posCPEP_high; n = 327) and patients with type 2 diabetes (GAD_negCPEP_high; n = 3544). Patients with LADA defined an intermediate group with higher HbA_1c but otherwise lower cardiometabolic risk than patients with type 2 diabetes.

CONCLUSIONS

Our results demonstrate that fasting C-peptide and GADab status, but not age at onset, define groups of patients with diabetes with clinically relevant differences in glycaemic control and cardiometabolic risk.

Preclinical carotid atherosclerosis in patients with latent autoimmune diabetes in adults (LADA), type 2 diabetes and classical type 1 diabetes

BACKGROUND

LADA is probably the most prevalent form of autoimmune diabetes. Nevertheless, there are few data about cardiovascular disease in this group of patients. The aim of this study was to investigate the frequency of carotid atherosclerotic plaques in patients with LADA as compared with patients with classic type 1 diabetes and type 2 diabetes.

METHODS

Patients with LADA were matched for age and gender in different proportions to patients with type 2 diabetes, and classic type 1 diabetes. None of the patients had clinical cardiovascular disease. All subjects underwent B-mode carotid ultrasound to detect atheroma plaques. Demographics were obtained from all subjects.

RESULTS

We included 71 patients with LADA, 191 patients with type 2 diabetes and 116 patients with type 1 diabetes. Carotid atherosclerosis was more frequent in patients with LADA compared with type 2 diabetes (73.2% vs. 56.9%, P = 0.0018) and classic type 1 diabetes (57.1%, P = 0.026); these changes occurred despite healthier macrovascular risk profiles in the former. Age (P < 0.001), smoking (P = 0.003) and hypertension (P = 0.019) were independently associated with carotid atherosclerosis. Multiple plaques were also more frequent in patients with LADA as compared with classic type 1 diabetes and type 2 diabetes (45.1% and 33.6% vs. 27.2%, respectively, P = 0.022). The frequency of carotid plaques increased with increasing diabetes duration in LADA patients compared with type 2 diabetes (85.7% vs. 58.8%, inverse OR 5.72 [1.5-21.8]; P = 0.009).

CONCLUSIONS

LADA patients do not present with less carotid atherosclerosis than patients with type 1 and type 2 diabetes. Their macrovascular risk occurs despite a healthier macrovascular risk profile than those patients with type 2 diabetes.

Association of sarcopenia with both latent autoimmune diabetes in adults and type 2 diabetes: a cross-sectional study

BACKGROUND

To investigate the association of both latent autoimmune diabetes in adults (LADA) and type 2 diabetes (T2DM) with muscle mass and function (sarcopenia).

METHODS

Japanese patients with LADA (N=20), T2DM (N=208), and control subjects (N=41) were included in this cross-sectional study. The definition of LADA was based on age of onset (≥30), positive glutamic acid decarboxylase autoantibodies, and insulin requirement within the first 6months after diagnosis. Sarcopenia was diagnosed by the criteria for Asians, using skeletal muscle index (male <7.0 and female <5.4) and grip strength (male <26.0kg and female <18.0kg). The odds ratio (OR) with a 95% confidence interval (CI) was estimated using logistic regression.

RESULTS

The prevalence of sarcopenia was higher in LADA (35.0%) than in either T2DM (13.3%) or control subjects (9.8%). LADA was significantly associated with an increased risk for sarcopenia in a multivariate model in which age and body mass index were incorporated (OR: 9.57, 95% CI: 1.86-49.27). In contrast, T2DM tended to be associated with an increased risk for sarcopenia (OR: 2.99, 95% CI: 0.83-10.80).

CONCLUSIONS

This study provides evidence that patients with LADA are at a high risk for sarcopenia compared to those with T2DM or to control subjects.

Autoimmune diabetes in adults and risk of myocardial infarction: the HUNT study in Norway

BACKGROUND

The long-term consequences of autoimmune diabetes in adults (AIDA) are largely unexplored.

OBJECTIVE

To investigate the risk of myocardial infarction (MI) in AIDA compared to type 2 diabetes, taking into consideration the effects of socio-economic and lifestyle factors, the metabolic syndrome and glycaemic control.

METHODS

A total of 62 995 participants including 207 individuals with AIDA (onset ≥35 years and anti-GAD positive) and 2322 individuals with type 2 diabetes (onset ≥35 years and anti-GAD negative), from the population-based Norwegian HUNT study, were followed for a first MI during the period 1995-2008. We identified 2614 MIs by hospital records or the National Cause of Death Registry. Cox proportional hazard models were used to estimate the risk of MI by diabetes subgroups after adjustment for age and socio-economic and lifestyle factors.

RESULTS

AIDA amongst women was associated with a nearly fourfold increased risk of MI [hazard ratio (HR) 3.63, 95% confidence interval (CI) 2.21-5.96) compared to nondiabetic participants, whereas no excess risk was found in men with AIDA (HR 1.30, 95% CI 0.70-2.52). By contrast, type 2 diabetes was associated with an increased MI risk in both men (HR 1.92, 95% CI 1.62-2.26) and women (HR 2.39, 95% CI 1.98-2.89). The metabolic profile was more favourable in patients with AIDA than in those with type 2 diabetes, but glycaemic control was worse. Multivariable models and sensitivity analyses suggest that these results were robust.

CONCLUSIONS

Women with AIDA were more likely to develop MI, compared to men with AIDA and both men and women with type 2 diabetes. Further investigations are warranted to confirm this gender difference.

Should There be Concern About Autoimmune Diabetes in Adults? Current Evidence and Controversies

Autoimmune diabetes has a heterogeneous phenotype. Although often considered a condition starting in childhood, a substantial proportion of type 1 diabetes presents in adult life. This holds important implications for our understanding of the factors that modify the rate of progression through the disease prodrome to clinical diabetes and for our management of the disease. When autoimmune diabetes develops in adulthood, insulin treatment is often not required at the time of diagnosis, and this autoimmune non-insulin requiring diabetes is generally termed latent autoimmune diabetes in adults (LADA). Patients with LADA are generally leaner, younger at diabetes onset; have a greater reduction in C-peptide; and have a greater likelihood of insulin treatment as compared with patients with type 2 diabetes. The LADA subset of patients with adult-onset autoimmune diabetes has highlighted many shortcomings in the classification of diabetes and invokes the case for more personalized data analysis in line with the move towards precision medicine. Perhaps most importantly, the issues highlight our persistent failure to engage with the heterogeneity within the most common form of autoimmune diabetes, that is adult-onset type 1 diabetes, both insulin-dependent and initially non-insulin requiring (LADA). This review discusses characteristics of autoimmune diabetes and specifically aims to illustrate the heterogeneity of the disease.

The Clinical Significance of Glycoprotein Phospholipase D Levels in Distinguishing Early Stage Latent Autoimmune Diabetes in Adults and Type 2 Diabetes

Autoantibodies have been widely used as markers of latent autoimmune diabetes in adults (LADA); however, the specificity and sensitivity of autoantibodies as markers of LADA are weak compared with those found in type 1 diabetes (T1DM). In this study, we aimed to identify other plasma proteins as potential candidates that can be used effectively to determine early stage LADA and type 2 diabetes (T2DM) to facilitate early diagnosis and treatment. These issues were addressed by studying new-onset ‘classic’ T1DM (n = 156), LADA (n = 174), T2DM (n = 195) and healthy cohorts (n = 166). Plasma samples were obtained from the four cohorts. We employed isobaric tag for relative and absolute quantitation (iTRAQ) together with liquid chromatography tandem mass spectrometry (LC-MS) to identify plasma proteins with significant changes in LADA. The changes were validated by Western blot and ELISA analyses. Among the four cohorts, 311 unique proteins were identified in three iTRAQ runs, with 157 present across the three data sets. Among them, 49/311 (16.0%) proteins had significant changes in LADA compared with normal controls, including glycoprotein phospholipase D (GPLD1), which was upregulated in LADA. Western blot and ELISA analyses showed that GPLD1 levels were higher in both LADA and T1DM cohorts than in both T2DM and healthy cohorts, while there were no significant differences in the plasma concentrations of GPLD1 between the LADA and T1DM cohorts. GPLD1 is implicated as a potential candidate plasma protein for determining early stage LADA and T2DM.

Diabetes at the crossroads: relevance of disease classification to pathophysiology and treatment

Diabetes is not a single homogeneous disease but composed of many diseases with hyperglycaemia as a common feature. Four factors have, historically, been used to identify this diversity: the age at onset; the severity of the disease, i.e. degree of loss of beta cell function; the degree of insulin resistance and the presence of diabetes-associated autoantibodies. Our broad understanding of the distinction between the two major types, type 1 diabetes mellitus and type 2 diabetes mellitus, are based on these factors, but it has become apparent that they do not precisely capture the different disease forms. Indeed, both major types of diabetes have common features, encapsulated by adult-onset autoimmune diabetes and maturity-onset diabetes of the young. As a result, there has been a repositioning of our understanding of diabetes. In this review, drawing on recent literature, we discuss the evidence that autoimmune type 1 diabetes has a broad clinical phenotype with diverse therapeutic options, while the term non-autoimmune type 2 diabetes obscures the optimal management strategy because it encompasses substantial heterogeneity. Underlying these developments is a general progression towards precision medicine with the need for precise patient characterisation, currently based on clinical phenotypes but in future augmented by laboratory-based tests.

Geospatial analysis of food environment demonstrates associations with gestational diabetes

BACKGROUND

Gestational diabetes mellitus (GDM) is one of most common complications of pregnancy, with incidence rates varying by maternal age, race/ethnicity, obesity, parity, and family history. Given its increasing prevalence in recent decades, covariant environmental and sociodemographic factors may be additional determinants of GDM occurrence.

OBJECTIVE

We hypothesized that environmental risk factors, in particular measures of the food environment, may be a diabetes contributor. We employed geospatial modeling in a populous US county to characterize the association of the relative availability of fast food restaurants and supermarkets to GDM.

STUDY DESIGN

Utilizing a perinatal database with >4900 encoded antenatal and outcome variables inclusive of ZIP code data, 8912 consecutive pregnancies were analyzed for correlations between GDM and food environment based on countywide food permit registration data. Linkage between pregnancies and food environment was achieved on the basis of validated 5-digit ZIP code data. The prevalence of supermarkets and fast food restaurants per 100,000 inhabitants for each ZIP code were gathered from publicly available food permit sources. To independently authenticate our findings with objective data, we measured hemoglobin A1c levels as a function of geospatial distribution of food environment in a matched subset (n = 80).

RESULTS

Residence in neighborhoods with a high prevalence of fast food restaurants (fourth quartile) was significantly associated with an increased risk of developing GDM (relative to first quartile: adjusted odds ratio, 1.63; 95% confidence interval, 1.21-2.19). In multivariate analysis, this association held true after controlling for potential confounders (P = .002). Measurement of hemoglobin A1c levels in a matched subset were significantly increased in association with residence in a ZIP code with a higher fast food/supermarket ratio (n = 80, r = 0.251 P < .05).

CONCLUSION

As demonstrated by geospatial analysis, a relationship of food environment and risk for gestational diabetes was identified.

Latent autoimmune diabetes of the adult: current knowledge and uncertainty

Patients with adult-onset autoimmune diabetes have less Human Leucocyte Antigen (HLA)-associated genetic risk and fewer diabetes-associated autoantibodies compared with patients with childhood-onset Type 1 diabetes. Metabolic changes at diagnosis reflect a broad clinical phenotype ranging from diabetic ketoacidosis to mild non-insulin-requiring diabetes, also known as latent autoimmune diabetes of the adult (LADA). This latter phenotype is the most prevalent form of adult-onset autoimmune diabetes and probably the most prevalent form of autoimmune diabetes in general. Although LADA is associated with the same genetic and immunological features as childhood-onset Type 1 diabetes, it also shares some genetic features with Type 2 diabetes, which raises the question of genetic heterogeneity predisposing to this form of the disease. The potential value of screening patients with adult-onset diabetes for diabetes-associated autoantibodies to identify those with LADA is emphasized by their lack of clinically distinct features, their different natural history compared with Type 2 diabetes and their potential need for a dedicated management strategy. The fact that, in some studies, patients with LADA show worse glucose control than patients with Type 2 diabetes, highlights the need for further therapeutic studies. Challenges regarding classification, epidemiology, genetics, metabolism, immunology, clinical presentation and treatment of LADA were discussed at a 2014 workshop arranged by the Danish Diabetes Academy. The presentations and discussions are summarized in this review, which sets out the current ideas and controversies surrounding this form of diabetes.

Latent autoimmune diabetes in adults with low-titer GAD antibodies: similar disease progression with type 2 diabetes: a nationwide, multicenter prospective study (LADA China Study 3)

OBJECTIVE

This study investigated the relationship between GAD autoantibody (GADA) titers and changing of β-cell function in patients with latent autoimmune diabetes in adults (LADA).

RESEARCH DESIGN AND METHODS

This 3-year prospective study enrolled 95 subjects from 15 Chinese cities including 25 high-titer (GADA ≥180 units/mL) LADA patients, 42 low-titer (GADA <180 units/mL) LADA patients, and 28 type 2 diabetic patients, the latter two groups as controls of similar age, sex, and BMI. Clinical characteristics were determined annually, including glycosylated hemoglobin (HbA1c), fasting C-peptide (FCP), and 2-h postprandial C-peptide (PCP).

RESULTS

Despite similar initial FCP and PCP, FCP and PCP both decreased more in subjects with high GADA titer (FCP from mean 0.49 nmol/L at entry to 0.13 nmol/L at the third year; P < 0.05) than with low GADA titer (FCP from mean 0.48 to 0.38 nmol/L) and type 2 diabetes (FCP from mean 0.47 to 0.36 nmol/L); the latter two groups being similar. After 3 years, residual β-cell function (FCP >0.2 nmol/L) was detected in only 42% with an initial high GADA titer compared with 90% with a low GADA titer and 97% with type 2 diabetes (P < 0.01 for both). GADA positivity at the third year persisted more in subjects with initially high GADA (92%) than with low GADA (26%) titers (P < 0.01).

CONCLUSIONS

In selected LADA patients, initial GADA titers identified subjects with different degrees of persistent autoimmunity and disease progression. LADA patients with a low GADA titer had metabolic phenotypes and loss of β-cell function similar to type 2 diabetic patients.

LADA and CARDS: a prospective study of clinical outcome in established adult-onset autoimmune diabetes

OBJECTIVE

Diabetes-associated autoantibodies can be detected in adult-onset diabetes, even when initially non-insulin requiring, i.e., with latent autoimmune diabetes. We aimed to identify adult-onset autoimmune diabetes in patients with established "type 2 diabetes" participating in the Collaborative Atorvastatin Diabetes Study (CARDS) to characterize their phenotype and clinical outcome.

RESEARCH DESIGN AND METHODS

We prospectively studied 2,425 European patients with presumed type 2 diabetes (mean age 62 years, diabetes duration 7.9 years) for outcomes at 3.9 years after randomization to either atorvastatin or placebo. Subjects were screened for autoantibodies to GAD (GADA), insulinoma-associated antigen-2 (IA-2A), and zinc-transporter 8 (ZnT8A).

RESULTS

A total of 173 patients (7.1%) had GADA, of whom 11 (0.5%) and 5 (0.2%) were also positive for IA-2A and ZnT8A, respectively. At baseline, 44% of GADA-positive patients were not on insulin. Fewer autoantibody-positive than autoantibody-negative patients had metabolic syndrome (64 vs. 80%), and more were on insulin (56 vs. 17%) (P < 0.0001 for each) without lower HbA1c (69 mmol/mol [8.5%] vs. 62 mmol/mol [7.8%]). The frequency of microvascular and macrovascular events was similar in both cohorts, independent of atorvastatin.

CONCLUSIONS

Adult-onset autoimmune diabetes was prevalent, even in patients with established diabetes presumed to have type 2 diabetes. After 11.8 years' diabetes duration, nearly half the patients with autoimmune diabetes were not on insulin treatment and almost two-thirds had metabolic syndrome. The type of diabetes, whether autoimmune diabetes or type 2 diabetes, did not impact the risk of microvascular disease.

Dipeptidyl peptidase 4 inhibitor sitagliptin maintains β-cell function in patients with recent-onset latent autoimmune diabetes in adults: one year prospective study

CONTEXT

Dipeptidyl peptidase 4 (DPP-4) inhibitors have been widely used in type 2 diabetes. An important unanswered question concerns the effect of DPP-4 inhibition on β-cell function in patients with autoimmune diabetes.

OBJECTIVE

The objective of the study was to investigate the effects of the DPP-4 inhibitor on β-cell function in patients with recent-onset latent autoimmune diabetes in adults (LADA).

DESIGN AND SETTING

This study was an open-label, randomized-controlled study conducted in the Department of Endocrinology at the Second Xiangya Hospital.

PATIENTS AND INTERVENTION

Thirty recently diagnosed LADA patients were randomized 1:1 to receive insulin therapy with 100 mg/d sitagliptin (group A, n = 15) or without sitagliptin (group B, n = 15) for 12 months.

MAIN OUTCOME MEASURES

Fasting and 2-hour postprandial blood samples were obtained at baseline and after 3, 6, 9, and 12 months of treatment to determine blood glucose, glycosylated hemoglobin, and C-peptide levels.

RESULTS

There were no differences in the clinical baseline data between the two groups. During the 12 months of follow-up, there were no significant differences in glucose and glycosylated hemoglobin levels between the two groups. At 12 months, fasting C-peptide (FCP), 2-hour postprandial C-peptide (CP), and ΔCP (ΔCP = 2 h CP-FCP) levels were not different in group A (P > .05) compared with baseline, whereas in group B the levels of FCP, 2-hour CP and ΔCP were significantly decreased compared with baseline (P < .05). Levels of 2-hour CP were higher in group A than group B at 12 months (P < .05).

CONCLUSIONS

LADA patients treated with sitagliptin and insulin maintained β-cell function by comparison with insulin alone.

Mortality in adult-onset autoimmune diabetes is associated with poor glycemic control: results from the HUNT Study

OBJECTIVE

Knowledge on mortality in autoimmune diabetes with adult onset is limited. We compared mortality in adult-onset autoimmune diabetes and type 2 diabetes, taking into account metabolic risk factors, HbA1c, lifestyle, and socioeconomic factors.

RESEARCH DESIGN AND METHODS

Participants of the population-based HUNT2 Study (second survey of the Norwegian HelseUndersøkelsen i Nord-Trøndelag Study; n = 64,264) were followed up prospectively for mortality in the Cause of Death Registry (1995-2009). Diabetes with onset ≥35 years was classified as autoimmune diabetes in adults if anti-GAD was positive (n = 208) and as type 2 diabetes if anti-GAD was negative (n = 2,425). Hazard ratios (HRs) of mortality from all-causes, cardiovascular disease (CVD), and ischemic heart disease (IHD) were calculated using the Cox proportional hazards model.

RESULTS

Prevalence of the metabolic syndrome was lower in autoimmune diabetes than in type 2 diabetes (55 vs. 77%, P < 0.001). Still, autoimmune diabetes was associated with an increased risks of mortality from all-causes (HR 1.55 [95% CI 1.25-1.92]), CVD (1.87 [1.40-2.48]), and IHD (2.39 [1.57-3.64]), equally high as in type 2 diabetes in analyses where individuals without diabetes were used as the reference group. The increased risk was not explained by overweight, lifestyle, socioeconomic position, or presence of the metabolic syndrome. Excess mortality was primarily observed in individuals with elevated HbA1c.

CONCLUSIONS

Mortality in autoimmune diabetes was as high as in type 2 diabetes, despite a more favorable baseline metabolic risk profile. Excess risk was associated with poor glycemic control. The results from this study, the largest so far on mortality in autoimmune diabetes in adults, underscore the importance of optimal treatment modalities to improve survival in adult-onset autoimmune diabetes.