High Prevalence of Autoimmune Diabetes and Poor Glycaemic Control among Adults in Madagascar: A Brief Report from a Humanitarian Health Campaign in Ambanja

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.

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.

Risk of cardiac autonomic neuropathy in latent autoimmune diabetes in adults is similar to type 1 diabetes and lower compared to type 2 diabetes: A cross-sectional study

AIMS

Microvascular complications' risk differs between people with latent autoimmune diabetes in adults (LADA) and people with type 2 diabetes. We aimed to investigate whether the prevalence of cardiac autonomic neuropathy, a life-threatening complication of diabetes, also varies depending on diabetes type.

METHODS

In this cross-sectional study, 43 adults with LADA, 80 with type 1 diabetes and 61 with type 2 diabetes were screened for cardiac autonomic neuropathy with recommended tests. Logistic regression models were used to test differences between diabetes types adjusting for confounders.

RESULTS

Cardiac autonomic neuropathy was diagnosed in 17 (40%) participants with LADA, 21 (26%) participants with type 1 diabetes and 39 (64%) participants with type 2 diabetes (p < 0.001). The odds ratio (OR) for cardiac autonomic neuropathy in type 1 diabetes and in type 2 diabetes compared to LADA were 0.54 (95% CI: 0.25-1.20, p-value: 0.13) and 2.71 (95% CI: 1.21-6.06, p-value 0.015) respectively. Smoking (_adj OR 3.09, 95% CI: 1.40-6.82, p-value: 0.005), HDL cholesterol (_adj OR 0.29, 95% CI: 0.09-0.93, p-value: 0.037) and hypertension (_adj OR 2.11, 95% CI: 1.05-4.24, p-value: 0.037) were independent modifiable risk factors for cardiac autonomic neuropathy. Differences among diabetes types did not change after correction for confounders.

CONCLUSIONS

This is the first study offering a comparative evaluation of cardiac autonomic neuropathy among LADA, type 1 and type 2 diabetes, showing a lower risk of cardiac autonomic neuropathy in LADA compared to type 2 diabetes and similar compared to type 1 diabetes. This disparity was not due to differences in age, metabolic control or cardiovascular risk factors.

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.

"H" for Heterogeneity in the Algorithm for Type 2 Diabetes Management

PURPOSE OF REVIEW

Genetic, socioeconomic and clinical features vary considerably among individuals with type 2 diabetes (T2D) influencing disease development, progression and response to therapy. Although a patient-centred approach to pharmacologic therapy of T2D is widely recommended, patients are often treated similarly, irrespective of the differences that may affect therapeutic response. Addressing the heterogeneity of T2D is a major task of diabetes research to lower the high rate of treatment failure as well as to reduce the risk of long-term complications.

RECENT FINDINGS

A pathophysiology-based clustering system seems the most promising to help in the stratification of diabetes in terms of complication risk and response to treatment. This urges for clinical studies looking at novel biomarkers related to the different metabolic pathways of T2D and able to inform about the therapeutic cluster of each patient. Here, we review the main settings of diabetes heterogeneity, to what extent it has been already addressed and the current gaps in knowledge towards a personalized therapeutic approach that considers the distinctive features of each patient.

Time-varying risk of microvascular complications in latent autoimmune diabetes of adulthood compared with type 2 diabetes in adults: a post-hoc analysis of the UK Prospective Diabetes Study 30-year follow-up data (UKPDS 86)

BACKGROUND

Latent autoimmune diabetes of adulthood (LADA) differs in clinical features from type 2 diabetes. Whether this difference translates into different risks of complications remains controversial. We examined the long-term risk of microvascular complications in people enrolled in the UK Prospective Diabetes Study (UKPDS), according to their diabetes autoimmunity status.

METHODS

We did a post-hoc analysis of 30-year follow-up data from UKPDS (UKPDS 86). UKPDS participants with diabetes autoantibody measurements available and without previous microvascular events were included. Participants with at least one detectable autoantibody were identified as having latent autoimmune diabetes, and those who tested negative for all autoantibodies were identified as having type 2 diabetes. The incidence of the primary composite microvascular outcome (first occurrence of renal failure, renal death, blindness, vitreous haemorrhage, or retinal photocoagulation) was compared between adults with latent autoimmune diabetes and those with type 2 diabetes. The follow-up ended on Sept 30, 2007. Baseline and updated 9-year mean values of potential confounders were tested in Cox models to adjust hazard ratios (HRs). UKPDS is registered at the ISRCTN registry, 75451837.

FINDINGS

Among the 5028 participants included, 564 had latent autoimmune diabetes and 4464 had type 2 diabetes. After median 17·3 years (IQR 12·6-20·7) of follow-up, the composite microvascular outcome occurred in 1041 (21%) participants. The incidence for the composite microvascular outcome was 15·8 (95% CI 13·4-18·7) per 1000 person-years in latent autoimmune diabetes and 14·2 (13·3-15·2) per 1000 person-years in type 2 diabetes. Adults with latent autoimmune diabetes had a lower risk of the composite outcome during the first 9 years of follow-up than those with type 2 diabetes (adjusted HR 0·45 [95% CI 0·30-0·68], p<0·0001), whereas in subsequent years their risk was higher than for those with type 2 diabetes (1·25 [1·01-1·54], p=0·047). Correcting for the higher updated 9-year mean HbA_1c seen in adults with latent autoimmune diabetes than in those with type 2 diabetes explained entirely their subsequent increased risk for the composite microvascular outcome (adjusted HR 0·99 [95% CI 0·80-1·23], p=0·93).

INTERPRETATION

At diabetes onset, adults with latent autoimmune diabetes have a lower risk of microvascular complications followed by a later higher risk of complications than do adults with type 2 diabetes, secondary to worse glycaemic control. Implementing strict glycaemic control from the time of diagnosis could reduce the later risk of microvascular complications in adults with latent autoimmune diabetes.

FUNDING

European Foundation for the Study of Diabetes Mentorship Programme (AstraZeneca).

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.

Long-term risk of cardiovascular disease in individuals with latent autoimmune diabetes in adults (UKPDS 85)

AIMS

Latent autoimmune diabetes in adults (LADA) is diagnosed in up to 12% of adults with clinically diagnosed type 2 diabetes (T2D). LADA tends to have healthier cardiovascular (CV) risk profiles than T2D, but it remains uncertain whether the risk of CV events differs between the two. We examined the risk of CV events in patients enrolled in the United Kingdom Prospective Diabetes Study (UKPDS) according to LADA status.

MATERIALS AND METHODS

Diabetes autoantibodies (AAb) were measured in 5062 UKPDS participants. The incidence of major adverse CV events (MACE), defined as CV death, non-fatal myocardial infarction or non-fatal stroke, was compared in those with LADA (≥1 AAb test positive) and those without LADA (AAb negative).

RESULTS

There were 567 participants (11.2%) with LADA. Compared with participants with T2D, they were younger, with higher mean HbA1c and HDL-cholesterol values, and with lower body mass index and total cholesterol and systolic blood pressure values (all P < 0.01). After a median (25th, 75th percentile) 17.3 (12.6-20.7) years of follow-up, MACE occurred in 157 (17.4 per 1000 person-years) participants with LADA and in 1544 (23.5 per 1000 person-years) participants with T2D (HR, 0.73; 95% confidence interval [CI], 0.62-0.86; P < 0.001). However, after adjustment for confounders, this difference was no longer significant (HR_adj , 0.90; 95% CI, 0.76-1.07; P = 0.22).

CONCLUSIONS

In adults thought to have newly diagnosed T2D, the long-term risk of MACE was lower in those with LADA. However, this did not differ after adjustment for traditional CV risk factors, suggesting that measurement of AAb in addition to traditional CV risk factors will not aid in stratification of CV risk in clinically diagnosed T2D.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Increased circulating granzyme B in type 2 diabetes patients with low-grade systemic inflammation

In metabolic diseases, like type 2 diabetes (T2D), adipose tissue (AT) is infiltrated by macrophages and other leukocytes - which secrete many bioactive peptides leading to local and systemic low-grade chronic inflammation - and undergoes remodeling and aberrant fibrosis. Granzyme B (GrB) is a serine protease produced by some leukocytes, including cytotoxic lymphocytes and macrophages. It exerts both intracellular apoptotic function and extracellular functions, leading to tissue injury, inflammation and repair. Elevated circulating GrB levels have been found in aging- and inflammation-associated diseases and a role for GrB in the pathogenesis of several chronic inflammatory diseases has been reported. Aims of this study were to investigate circulating GrB levels in T2D patients in relation to their systemic inflammatory profile and to unravel its correlates. For this cross-sectional study, we recruited 51 consecutive T2D patients referring to our diabetes outpatient clinics (Sapienza University, Rome, Italy) for metabolic evaluations, and 29 sex, age and body mass index comparable non-diabetic subjects as control group. Study participants underwent clinical work-up; fasting blood sampling was performed for routine biochemistry and for inflammatory profile (CRP, IL-2, IL-4, IL-6, IL-8, IL-10, TNF-α, IFN-γ, GM-CSF, adiponectin, WISP1); serum GrB was measured by Human Granzyme-B Platinum Elisa kit (Affymetrix EBIO). We found that T2D patients had serum levels of GrB significantly higher than the control group (10.17 ± 12.6 vs 7.2 ± 14.1 pg/ml, p = 0.03). Moreover, in T2D patients increased GrB correlated with unfavorable inflammatory profile, as described by elevated levels of validated adipokines such as IL-6 (p = 0.04), TNF-α (p = 0.019) and WISP1 (p = 0.005). Furthermore, multivariate linear regression analysis showed that increased GrB was associated with T2D diagnosis independently from possible confounders. In conclusion, our results show that increased levels of circulating GrB are associated with T2D diagnosis and correlates with markers of AT-linked systemic inflammation, suggesting a potential role for GrB in the inflammatory and reactive processes occurring in metabolic diseases.