Endocrine autoimmunity in families with type 1 diabetes: frequent appearance of thyroid autoimmunity during late childhood and adolescence

Autoantibodies against ATP4A are a feature of the abundant autoimmunity that develops in first-degree relatives of patients with type 1 diabetes

OBJECTIVE

Type 1 diabetes is associated with autoantibodies to different organs that include the gut. The objective of the study was to determine the risk of developing gastric parietal cell autoimmunity in relation to other autoimmunity in individuals with a family history of type 1 diabetes.

METHODS

Autoantibodies to the parietal cell autoantigen, H⁺ /K⁺ ATPase subunit A (ATP4A) was measured in 2218 first-degree relatives of patients with type 1 diabetes, who were prospectively followed from birth for a median of 14.5 years. All were also tested regularly for the development of islet autoantibodies, transglutaminase autoantibodies, and thyroid peroxidase autoantibodies.

RESULTS

The cumulative risk to develop ATP4A autoantibodies was 8.1% (95% CI, 6.6-9.6) by age 20 years with a maximum incidence observed at age 2 years. Risk was increased in females (HR, 1.9; 95% CI, 1.3-2.8; p = 0.0004), relatives with the HLA DR4-DQ8/DR4-DQ8 genotype (HR, 3.4; 95% CI, 1.9-5.9; p < 0.0001) and in participants who also had thyroid peroxidase autoantibodies (HR, 3.7; 95% CI, 2.5-5.5; p < 0.0001). Risk for at least one of ATP4A-, islet-, transglutaminase-, or thyroid peroxidase-autoantibodies was 24.7% (95% CI, 22.6-26.7) by age 20 years and was 47.3% (95% CI, 41.3-53.3) in relatives who had an HLA DR3/DR4-DQ8, DR4-DQ8/DR4-DQ8, or DR3/DR3 genotype (p < 0.0001 vs. other genotypes).

CONCLUSIONS

Relatives of patients with type 1 diabetes who have risk genotypes are at very high risk for the development of autoimmunity against gastric and other organs.

A classification and regression tree analysis identifies subgroups of childhood type 1 diabetes

Background

Diabetes in childhood and adolescence includes autoimmune and non-autoimmune forms with heterogeneity in clinical and biochemical presentations. An unresolved question is whether there are subtypes, endotypes, or theratypes within these forms of diabetes.

Methods

The multivariable classification and regression tree (CART) analysis method was used to identify subgroups of diabetes with differing residual C-peptide levels in patients with newly diagnosed diabetes before 20 years of age (n=1192). The robustness of the model was assessed in a confirmation and prognosis cohort (n=2722).

Findings

The analysis selected age, haemoglobin A1c (HbA1c), and body mass index (BMI) as split parameters that classified patients into seven islet autoantibody-positive and three autoantibody-negative groups. There were substantial differences in genetics, inflammatory markers, diabetes family history, lipids, 25-OH-Vitamin D3, insulin treatment, insulin sensitivity and insulin autoimmunity among the groups, and the method stratified patients with potentially different pathogeneses and prognoses. Interferon-ɣ and/or tumour necrosis factor inflammatory signatures were enriched in the youngest islet autoantibody-positive groups and in patients with the lowest C-peptide values, while higher BMI and type 2 diabetes characteristics were found in older patients. The prognostic relevance was demonstrated by persistent differences in HbA1c at 7 years median follow-up.

Interpretation

This multivariable analysis revealed subgroups of young patients with diabetes that have potential pathogenetic and therapeutic relevance.

Funding

The work was supported by funds from the German Federal Ministry of Education and Research (01KX1818; FKZ 01GI0805; DZD e.V.), the Innovative Medicine Initiative 2 Joint Undertaking INNODIA (grant agreement No. 115797), the German Robert Koch Institute, and the German Diabetes Association.

Autoimmune thyroid disease correlates to islet autoimmunity on zinc transporter 8 autoantibody

OBJECTIVE

The most common coexisting organ-specific autoimmune disease in patients with type 1 diabetes mellitus (T1DM) is autoimmune thyroid disease (AITD). However, there have been few clinical reports based on a large population about the prevalence of zinc transporter 8 autoantibody (ZnT8A) and other islet autoantibodies in AITD patients. We aimed to explore the presence of islet autoantibodies, ZnT8A, glutamic acid decarboxylase autoantibodies (GADA) and insulinoma-associated antigen 2 autoantibodies (IA-2A) compared with thyroid autoantibodies, thyroid peroxidase autoantibodies (TPOAb) and thyroglobulin autoantibodies (TGAb) and thyrotropin receptor autoantibodies (TRAb) in patients with Graves' disease (GD), Hashimoto's thyroiditis (HT) and T1DM patients with AITD.

METHODS

Totally, 389 patients with GD, 334 patients with HT, 108 T1DM patients with AITD and 115 healthy controls (HC) were recruited in the study. Islet autoantibodies (ZnT8A, GADA and IA-2A) were detected by radioligand binding assay. Thyroid autoantibodies, TPOAb and TGAb were detected by chemiluminescence assay, and TRAb was detected by RIA.

RESULTS

The prevalence of ZnT8A, GADA and IA-2A was higher in GD and HT patients than that of HC (ZnT8A: GD 8.48%, HT 10.8% vs HC 1.74%; GADA: GD 7.46%, HT 7.74% vs HC 0.870%; IA-2A: GD 4.88%, HT 3.59% vs HC 0%; All P < 0.05) but lower than that of T1DM subjects with AITD (ZnT8A: 42.6%; IA-2A: 44.4%; GADA: 74.1%; all P < 0.0001).

CONCLUSIONS

An increased prevalence of ZnT8A as well as GADA and IA-2A was found in both GD and HT patients, indicating that there is a potential link between thyroid autoimmunity and islet autoimmunity.

Childhood thyroid autoimmunity and relation to islet autoantibodies in children at risk for type 1 diabetes in the diabetes prediction in skåne (DiPiS) study

BACKGROUND

The aim was to determine prevalence and age at seroconversion of thyroid autoimmunity in relation to islet autoantibodies, gender and HLA-DQ genotypes in children with increased risk for type 1 diabetes followed from birth.

METHODS

In 10-year-old children (n = 1874), blood samples were analysed for autoantibodies against thyroid peroxidase (TPOAb), thyroglobulin (TGAb), glutamic acid decarboxylase 65 (GADA), Zink transporter 8 (ZnT8R/W/QA), insulinoma-associated protein-2 (IA-2A), insulin (IAA) and HLA-DQ genotypes. Prospectively collected samples from 2 years of age were next analysed for TPOAb, and TGAb and, finally, in confirming samples at 11-16 years of age along with TSH and FT4. Frequencies were tested with Chi-square or Fischer's exact tests, autoantibody levels with Wilcoxon and correlations between autoantibody levels with Spearman's rank correlation test.

RESULTS

The prevalence of thyroid autoimmunity was 6.9%, overrepresented in girls (p < .001) also having higher TPOAb levels at 10 years (p = .049). TPOAb was associated with GADA (p = .002), ZnT8R/W/QA (p = .001) and IA-2A (p = .001) while TGAb were associated with ZnT8R/W/QA (p = .021). In boys only, TPOAb were associated with GADA (p = .002), IA-2A (p = .001), ZnT8R/W/QA (p = .001) and IAA (p = .009), and TGAb with GADA (p = .013), IA-2A (p = .005) and ZnT8R/W/QA (p = .003). Levels of IA-2A correlated to both TPOAb (p = .021) and to TGAb (p = .011). In boys only, levels of GADA and TGAb correlated (p = .009 as did levels of IA-2A and TPOAb (p = .013). The frequency and levels of thyroid autoantibodies increased with age. At follow-up, 22.3% had abnormal thyroid function or were treated with thyroxine.

CONCLUSIONS

Thyroid autoimmunity and high TPOAb levels were more common in girls. In contrast, in boys only, there was a strong association with as well as correlation between levels of thyroid and islet autoantibodies. It is concluded that while girls may develop autoimmune thyroid disease (AITD) independent of islet autoantibodies, the risk for thyroid disease in boys may be linked to concomitant islet autoimmunity.

Age, HLA, and Sex Define a Marked Risk of Organ-Specific Autoimmunity in First-Degree Relatives of Patients With Type 1 Diabetes

OBJECTIVE

Autoimmune diseases can be diagnosed early through the detection of autoantibodies. The aim of this study was to determine the risk of organ-specific autoimmunity in individuals with a family history of type 1 diabetes.

RESEARCH DESIGN AND METHODS

The study cohort included 2,441 first-degree relatives of patients with type 1 diabetes who were prospectively followed from birth to a maximum of 29.4 years (median 13.2 years). All were tested regularly for the development of autoantibodies associated with type 1 diabetes (islet), celiac disease (transglutaminase), or thyroid autoimmunity (thyroid peroxidase). The outcome was defined as an autoantibody-positive status on two consecutive samples.

RESULTS

In total, 394 relatives developed one (n = 353) or more (n = 41) of the three disease-associated autoantibodies during follow-up. The risk by age 20 years was 8.0% (95% CI 6.8-9.2%) for islet autoantibodies, 6.3% (5.1-7.5%) for transglutaminase autoantibodies, 10.7% (8.9-12.5%) for thyroid peroxidase autoantibodies, and 21.5% (19.5-23.5%) for any of these autoantibodies. Each of the three disease-associated autoantibodies was defined by distinct HLA, sex, genetic, and age profiles. The risk of developing any of these autoantibodies was 56.5% (40.8-72.2%) in relatives with HLA DR3/DR3 and 44.4% (36.6-52.2%) in relatives with HLA DR3/DR4-DQ8.

CONCLUSIONS

Relatives of patients with type 1 diabetes have a very high risk of organ-specific autoimmunity. Appropriate counseling and genetic and autoantibody testing for multiple autoimmune diseases may be warranted for relatives of patients with type 1 diabetes.

Glycemic control, complications, and associated autoimmune diseases in children and adolescents with type 1 diabetes in Jeddah, Saudi Arabia

Objectives:

To investigate the relationship between metabolic control, acute and long-term complications, the coexistence of autoimmune diseases, and to assess the different factors that can affect the glycemic control level among children with type 1 diabetes mellitus (T1DM).

Methods:

This is a cross-sectional study that included 228 T1DM children and adolescents visiting the pediatric diabetes clinic at the King Abdulaziz University Hospital (KAUH), Jeddah, Saudi Arabia from January 2013 to January 2014. The clinical and laboratory characteristics of the patients were recorded. Metabolic control, complications, and associated autoimmune diseases were evaluated.

Results:

The mean age of patients was 10.99 years, and the glycated hemoglobin (HbA1c) level was 8.8%. Acute complications included ketoacidosis in 65.4% of patients, and hypoglycemic attacks in 68.9%. Long-term complications were detected in patients including retinopathy (4.4%), microalbuminuria (16.2%), and dyslipidemia (8.3%). Autoimmune thyroiditis was noted in 14%, and celiac disease was found in 19.7% of patients. A significant difference was found in pubertal and pre-pubertal age groups in terms of glycemic control (p=0.01).

Conclusion:

The level of HbA1c was found to be higher among the pubertal age group. A relationship between autoimmune diseases and gender was determined.

Heritability of thyroid peroxidase autoantibody levels in type 1 diabetes: evidence from discordant twin pairs

AIMS/HYPOTHESIS

The discordance status of (autoimmune) type 1 diabetes within monozygotic twin pairs points to the importance of environmental factors. The aim of this study was to investigate whether the environmental events causing type 1 diabetes influence thyroid autoimmunity.

METHODS

Monozygotic and dizygotic twins discordant for type 1 diabetes from the UK and USA were tested for thyroid peroxidase autoantibodies (TPOA) by radioimmunoassay. Using quantitative genetic model fitting of a liability-threshold model we estimated the contribution of genetic (heritability) and environmental factors to TPOA.

RESULTS

TPOA positivity was higher in females than in males in both cohorts and was associated with later age at diagnosis in the UK and combined cohorts (p < 0.01). TPOA did not specifically segregate with type 1 diabetes in the twin pairs (p > 0.2 in all groups). The best-fitting models showed heritability (95% CI) estimates for TPOA of 63% (37%, 80%) for the UK and 80% (51%, 92%) for US twins, while the best-fitting meta-analysis model of the two twin cohorts combined included additive genetic and unique environmental factors with a heritability estimate of 69% (50%, 82%).

CONCLUSIONS/INTERPRETATION

Risk of thyroid autoimmunity, defined by TPOA, in the context of autoimmune diabetes is, substantially, genetically determined in discordant twin pairs. Environmental factors leading to type 1 diabetes were not the same as those involved with thyroid autoimmunity. It follows that it is as important to investigate for thyroid autoimmunity in relatives of type 1 diabetes patients as it is in the patients themselves.

Thyroid disorders are common in first-degree relatives of individuals with type 1 diabetes mellitus

OBJECTIVE

Thyroid diseases are common in individuals with type 1 diabetes mellitus (T1DM) and should be investigated annually in these individuals. The aim of this study was to evaluate the frequency of thyroid diseases in first degree relatives (FDR) of patients with T1DM.

SUBJECTS AND METHODS

Eighty individuals (40 patients with T1DM and 40 FDR) were interviewed and blood was sampled for thyroid-stimulating hormone (TSH), free thyroxine (FT4) and thyroid peroxidase (TPO) antibodies measurement. Autoantibodies against glutamic acid decarboxylase 65 (GAD65), islet antigen-2 (IA2) and autoantibodies against insulin (AAI) were measured in FDR.

RESULTS

We found a similar prevalence of thyroid dysfunction in patients with T1DM and their FDR (22.5% vs. 27.5%; p = 0,79). There were no differences in serum TSH levels (p = 0.29), FT4 (p = 0,45), frequency of abnormal TSH (p = 0.28), positive TPO antibodies (p = 0.13), titers of TPO antibodies (in positive cases) between patients with T1DM and their FDR (p = 0.94).

CONCLUSIONS

Thyroid abnormalities seem to be common not only in patients with T1DM but also in their FDR, which suggests that screening strategies for thyroid diseases might also be useful to these individuals.

Age-related islet autoantibody incidence in offspring of patients with type 1 diabetes

AIMS/HYPOTHESIS

Seroconversion to islet autoantibodies precedes type 1 diabetes. This study aimed to identify periods of high seroconversion incidence, which could be targeted for mechanistic and therapeutic studies.

METHODS

Incidence of islet autoantibodies was calculated in 1,650 genetically at-risk children followed with measurements of islet autoantibodies and thyroid autoantibodies at age 9 months and 2, 5, 8, 11, 14 and 17 years. Peak incidence periods were confirmed in a second cohort of 150 children followed until age 6 years with three-monthly samples up to age 3 years.

RESULTS

Islet autoantibody incidence (per 1,000 person-years) was 18.5 until age 9 months, 21 from 9 months to 2 years and <10 for intervals after age 2 years. The second cohort confirmed peak incidence around age 9 months and demonstrated an absence of seroconversion before this age. Seroconversion to insulin autoantibodies occurred earlier than other autoantibodies (p<0.01 against glutamic acid decarboxylase [GAD]-, insulinoma-associated protein 2 [IA-2]- and zinc transporter 8 [ZnT8]-autoantibodies). Early peak seroconversion incidence was most evident in children with high-risk HLA DR3/4-DQ8 or DR4/4-DQ8 genotypes.

CONCLUSION

The age period 9 months to 2 years is associated with a high incidence of activation of type 1 diabetes associated autoimmunity in genetically at-risk children and should be targeted for effective primary prevention strategies.

Age- and islet autoimmunity-associated differences in amino acid and lipid metabolites in children at risk for type 1 diabetes

OBJECTIVE

Islet autoimmunity precedes type 1 diabetes and often initiates in childhood. Phenotypic variation in islet autoimmunity relative to the age of its development suggests heterogeneous mechanisms of autoimmune activation. To support this notion, we examined whether serum metabolite profiles differ between children with respect to islet autoantibody status and the age of islet autoantibody development.

RESEARCH DESIGN AND METHODS

The study analyzed 29 metabolites of amino acid metabolism and 511 lipids assigned to 12 lipid clusters in children, with a type 1 diabetic parent, who first developed autoantibodies at age 2 years or younger (n = 13), at age 8 years or older (n = 22), or remained autoantibody-negative, and were matched for age, date of birth, and HLA genotypes (n = 35). Ultraperformance liquid chromatography and mass spectroscopy were used to measure metabolites and lipids quantitatively in the first autoantibody-positive and matched autoantibody-negative serum samples and in a second sample after 1 year of follow-up.

RESULTS

Differences in the metabolite profiles were observed relative to age and islet autoantibody status. Independent of age-related differences, autoantibody-positive children had higher levels of odd-chain triglycerides and polyunsaturated fatty acid-containing phospholipids than autoantibody-negative children and independent of age at first autoantibody appearance (P < 0.0001). Consistent with our hypothesis, children who developed autoantibodies by age 2 years had twofold lower concentration of methionine compared with those who developed autoantibodies in late childhood or remained autoantibody-negative (P < 0.0001).

CONCLUSIONS

Distinct metabolic profiles are associated with age and islet autoimmunity. Pathways that use methionine are potentially relevant for developing islet autoantibodies in early infancy.

Vaccination against type 1 diabetes

The clinical onset of type 1 diabetes or autoimmune diabetes occurs after a prodrome of islet autoimmunity. The warning signals for the ensuing loss of pancreatic islet beta cells are autoantibodies against insulin, GAD65, IA-2 and ZnT8, alone or in combinations. Autoantibodies against, for example, insulin alone have only a minor risk of type 1 diabetes. However, progression to clinical onset is increased by the induction of multiple islet autoantibodies. At the time of clinical onset, insulitis may be manifest, which seems to reduce the efficacy of immunosuppression. Autoantigen-specific immunotherapy with alum-formulated GAD65 (Diamyd(®)) shows promise to reduce the loss of beta-cell function after the clinical onset of type 1 diabetes. The mechanisms are unclear but may involve the induction of T regulatory cells, which may suppress islet autoantigen reactivity. Past and ongoing clinical trials have been safe. Future clinical trials, perhaps as combination autoantigen-specific immunotherapy, may increase the efficacy in preventing the clinical onset in subjects with islet autoantibodies or preserve residual beta-cell function in patients newly diagnosed with type 1 diabetes.

An interferon-induced helicase (IFIH1) gene polymorphism associates with different rates of progression from autoimmunity to type 1 diabetes

OBJECTIVE

Genome-wide association studies have identified gene regions associated with the development of type 1 diabetes. The aim of this study was to determine whether these associations are with the development of autoimmunity and/or progression to diabetes.

RESEARCH DESIGN AND METHODS

Children (n = 1,650) of parents with type 1 diabetes were prospectively followed from birth (median follow-up 10.20 years) for the development of islet autoantibodies, thyroid peroxidase antibodies, tissue transglutaminase antibodies, and diabetes. Genotyping for single-nucleotide polymorphisms of the PTPN22, ERBB3, PTPN2, KIAA0350, CD25, and IFIH1 genes was performed using the MassARRAY system with iPLEX chemistry.

RESULTS

Islet autoantibodies developed in 137 children and diabetes developed in 47 children. Type 1 diabetes risk was associated with the IFIH1 rs2111485 single-nucleotide polymorphism (hazard ratio 2.08; 95% CI 1.16-3.74; P = 0.014). None of the other genes were significantly associated with diabetes development in this cohort. IFIH1 genotypes did not associate with the development of islet autoantibodies (P = 0.80) or autoantibodies against thyroid peroxidase (P = 0.55) and tissue transglutaminase (P = 0.66). Islet autoantibody-positive children with the IFIH1 rs2111485 GG genotype had a faster progression to diabetes (31% within 5 years) than children with the type 1 diabetes protective GA or AA genotypes (11% within 5 years; P = 0.006).

CONCLUSIONS

The findings indicate that IFIH1 genotypes influence progression from autoimmunity to diabetes development, consistent with the notion that protective genotypes downregulate responses to environmental insults after initiation of autoimmunity.

German new onset diabetes in the young incident cohort study: DiMelli study design and first-year results

BACKGROUND

Diabetes incidence in childhood and youth is increasing worldwide, including autoimmune and non-autoimmune cases. Recent findings suggest that there is a larger than expected proportion of type 2 diabetes in youth, and potential cases of intermediate diabetes phenotypes. Most pediatric diabetes registries focus on type 1 diabetes. Also, there is an absence of reliable data on type 2 diabetes incidence in youth.

AIMS

The DiMelli study aims to establish a diabetes incidence cohort registry of patients in Germany, diagnosed with diabetes mellitus before age 20 years. It will be used to characterize diabetes phenotypes by immunologic, metabolic, and genetic markers. DiMelli will assess the contribution of obesity and socio-demographic factors to the development of diabetes in childhood and youth.

METHODS

Recruitment of patients started in 2009, and is expected to continue at a rate of 250 patients per year.

RESULTS

84% of the 216 patients recruited within the first year were positive for multiple islet autoantibodies, 12% for one islet autoantibody, and 4% were islet autoantibody-negative. Patients with multiple islet autoantibodies were younger and had lower fasting C-peptide levels, compared to islet autoantibody-negative patients (median age 10.0 vs. 14.1 years, p < 0.01).

CONCLUSIONS

Results from the first year of the study show that DiMelli will help to reveal new knowledge on the etiology of diabetes, and the contribution of genetic predisposition and environmental risk factors to the different types of diabetes.

Number of autoantibodies and HLA genotype, more than high titers of glutamic acid decarboxylase autoantibodies, predict insulin dependence in latent autoimmune diabetes of adults

OBJECTIVE

In latent autoimmune diabetes of adults (LADA), the progression into insulin-dependent diabetes is usually faster than in type 2 diabetes (T2D) but the factors influencing this progression are not completely known. In this study, we searched for sensitive markers associated with early development of insulin dependence.

DESIGN

The screening of 5568 T2D patients for glutamic acid decarboxylase autoantibodies (GAD65Ab) identified 276 LADA patients (M=131; F=145) and in 251 of them, tyrosine phosphatase-2 (IA-2Ab) and thyroperoxidase autoantibodies (TPOAbs), some clinical features and genotype variation of the main type 1 diabetes (T1D) disease susceptibility loci (HLA-DRB1 and HLA-DQB1) were analyzed.

RESULTS

Four years after the diagnosis of diabetes, high GAD65Ab titer was not significantly associated with faster progression toward insulin deficiency (P=0.104). Patients with GAD65Ab and TPOAb or IA-2Ab or triple positivity for both islet and TPOAbs (GAD65Ab/IA-2Ab/TPOAb) showed a significantly faster disease progression (P=0.002). Among 104 TPOAb-positive LADA patients, 10 received replacement therapy (l-thyroxine), 43 showed high TSH levels (62.7% developed insulin dependence), and 3 had hyperthyroidism treated with methimazole. Multivariate analysis revealed a significant effect on disease progression only for TPOAb (P=0.022), female gender (P=0.036), low body mass index (BMI; P=0.001), and T1D high/intermediate risk HLA-DRB1/DQB1 genotypes grouped (P=0.020).

CONCLUSIONS

High GAD65Ab titers per se are not a major risk factor for disease progression in LADA, while the number of positive autoantibodies and HLA DRB1-DQB1 genotypes at high risk for T1D are significant predictors. Moreover, clinical characteristics such as low BMI and female gender are more likely to identify patients who will require insulin therapy within 4 years of diagnosis.