Prevalence of diabetes and presence of autoantibodies against zinc transporter 8 and glutamic decarboxylase at diagnosis and at follow up of Graves' disease

Thyroid Eye Disease and Its Association With Diabetes Mellitus: A Major Review

PURPOSE

Thyroid eye disease (TED) associated with diabetes mellitus (DM) presents unique challenges. DM is a risk factor for TED. Standard management of TED with glucocorticoids (GC), orbital radiation, or teprotumumab can cause adverse events in poor glycemic control. The authors reviewed the literature on the relationship between TED and DM and the management of co-existing diseases.

METHODS

The authors searched PubMed with keywords "thyroid eye disease," "diabetes mellitus," and similar terms from 2013 to 2022. The authors included relevant studies after screening the abstracts. Additional references to the selected studies were included where applicable. Data were extracted from the final articles according to the preplanned outline of the review.

RESULTS

The initial search yielded 279 abstracts. The final review included 93 articles. TED and DM interact at multiple levels-genetic, immunologic, cellular, nutritional, and metabolic. Both DM and thyroid dysfunction exacerbate the morbidity caused by the other. Metabolic factors also affect the inflammatory pathway for TED. Patients with DM develop TED with greater frequency and severity, necessitating interventions for vision salvage. Agents (GC, teprotumumab, or radiation) used for TED are often unsuitable for treatment with DM, especially if there is poor glycemic control or diabetic retinopathy. There were no studies on using steroid-sparing agents in TED with DM.

CONCLUSION

TED and DM co-exist because of multiple intersections in the pathophysiology. Challenges in the treatment include increased TED severity and risk of hyperglycemia and retinopathy. Multidisciplinary teams best undertake treatment of TED with DM.

Anti-Islet Autoantibodies in Type 1 Diabetes

Anti-islet autoantibodies serve as key markers in immune-mediated type 1 diabetes (T1D) and slowly progressive T1D (SPIDDM), also known as latent autoimmune diabetes in adults (LADA). Autoantibodies to insulin (IAA), glutamic acid decarboxylase (GADA), tyrosine phosphatase-like protein IA-2 (IA-2A), and zinc transporter 8 (ZnT8A) are currently employed in the diagnosis, pathological analysis, and prediction of T1D. GADA can also be detected in non-diabetic patients with autoimmune diseases other than T1D and may not necessarily reflect insulitis. Conversely, IA-2A and ZnT8A serve as surrogate markers of pancreatic β-cell destruction. A combinatorial analysis of these four anti-islet autoantibodies demonstrated that 93-96% of acute-onset T1D and SPIDDM cases were diagnosed as immune-mediated T1D, while the majority of fulminant T1D cases were autoantibody-negative. Evaluating the epitopes and immunoglobulin subclasses of anti-islet autoantibodies help distinguish between diabetes-associated and non-diabetes-associated autoantibodies and is valuable for predicting future insulin deficiency in SPIDDM (LADA) patients. Additionally, GADA in T1D patients with autoimmune thyroid disease reveals the polyclonal expansion of autoantibody epitopes and immunoglobulin subclasses. Recent advancements in anti-islet autoantibody assays include nonradioactive fluid-phase assays and the simultaneous determination of multiple biochemically defined autoantibodies. Developing a high-throughput assay for detecting epitope-specific or immunoglobulin isotype-specific autoantibodies will facilitate a more accurate diagnosis and prediction of autoimmune disorders. The aim of this review is to summarize what is known about the clinical significance of anti-islet autoantibodies in the pathogenesis and diagnosis of T1D.

Screening of Organ-Specific Autoantibodies in a Large Cohort of Patients with Autoimmune Thyroid Diseases

Background: Autoimmune diseases tend to cluster in the same individual or in families. Four types of autoimmune polyglandular syndromes (APS) have been described based on the combination of endocrine and/or non-endocrine autoimmune diseases. In particular, type-3 APS is defined by the association of an autoimmune thyroid disease (ATD) and other autoimmune diseases and has a multifactorial etiology. The natural history of autoimmune diseases is characterized by three stages: potential, subclinical, and clinical. Methods: To determine the prevalence of organ-specific autoantibodies (anti-adrenal, anti-ovary [StCA], anti-pituitary [APA], anti-parietal cells [PCA], anti-tissue transglutaminase [tTGAb], anti-mitochondrial [AMA], anti-glutamic acid decarboxylase [GADA], anti-nicotinic acetylcholine receptor) in patients with ATD and to define the stage of the disease in patients with positive autoantibodies. From January 2016 to November 2018, 1502 patients (1302 female; age 52.7 ± 14.7 [mean ± standard deviation] years, range 18-86 years) with ATD (1285/1502 [85.6%] with chronic autoimmune thyroiditis and 217/1502 [14.4%] with Graves' disease) were prospectively enrolled. Results: The most common organ-specific autoantibodies were PCA (6.99%) and GADA (2.83%), while the prevalence of the remaining autoantibodies was ≤1%. All autoimmune diseases, but celiac disease, were predominant at the potential stage. Sex, ATD type, smoking habit, and coexistence of other autoimmune diseases correlated with the susceptibility to develop chronic atrophic gastritis (CAG) or autoimmune diabetes mellitus. Conclusions: The association between ATD and CAG was the most common manifestation of type-3 APS, mainly at the potential stage, that could lead to appropriate follow-up for early detection and timely treatment of the disease.

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.

Association between islet autoantibodies and the prevalence of autoimmune uveitis

AIM

To evaluate the predictive value of islet autoantibodies for the diagnosis of autoimmune uveitis (AU), as well as to characterize the association bet ween islet autoantibodies and AU.

METHODS

Totally 97 patients with AU and 100 healthy persons without any autoimmune diseases as the control group were recruited. Multiple serum islet autoantibodies were measured using commercial enzyme-linked immunosorbent assay kits (ELISA). A supplementary questionnaire was used to complement the subject's demographics and clinical features. The level of glucose concentrations and white blood cells were measured. Conditional logistic regression was performed to estimate odds ratios (ORs), and 95% confidence intervals (CIs) of AU according to islet autoantibodies and to evaluate the predictive value of islet autoantibodies for AU diagnosis. Autoantibodies subgroups and other variables were included into analysis.

RESULTS

In AU patients, the prevalence of detecting at least one of the autoantibodies was 31.9% (31/97). The most frequent autoantibody was ZnT8A (30.9%), followed by GADA (11.3%), IA-2A (4.1%), ICA (2.1%) and IAA (2.1%). Islet autoantibodies were found to be correlated positively with AU diagnosis [OR (95%CI): 13.86 (3.28, 58.50), P<0.001]. Moreover, Zn-T8A was remarkably correlated with AU diagnosis [OR (95%CI): 6.13 (1.96, 19.17), P<0.001], In contrast, neither GADA nor other islet antibodies (IA-2A, ICA and IAA) showed any association with AU risk under an additive model.

CONCLUSION

The prevalence of islet antibodies, especially ZnT8A, in patients with AU is higher. Islet antibodies as well as novel biomarkers should be included in routine evaluation at AU and is a valuable biological marker to classify newly-diagnosed uveitis.

Prevalence of latent and overt polyautoimmunity in autoimmune thyroid disease: A systematic review and meta-analysis

BACKGROUND

Thyroid autoimmunity is the most frequent condition involved in polyautoimmunity (PolyA). However, the frequency of latent and overt PolyA in patients with autoimmune thyroid disease (AITD) as the index condition is unknown. Therefore, the purpose of this study was to determine the prevalence of these types of PolyA in patients with AITD as the index condition.

METHODS

This study adhered to the relevant sections of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline. Searches through MEDLINE, Embase and LILACS were done to find articles in Spanish and English. Relevant vocabulary terms and key terms related to AITD and other autoimmune diseases were used. Two investigators independently screened the eligible studies, extracted data and assessed the quality and risk of bias. Fixed and random effect models were used accordingly. Cluster analysis was used to determine similarities among diseases in the articles included (based on Jaccard index).

RESULTS

A total of 56 articles fulfilled the inclusion criteria. Of these, 25 were case-controls, 17 were cohorts, and 14 were cross-sectional studies. These studies included a total of 47 509 patients. Female was the predominant gender and included 38 950 patients (81.23%, 95% CI: 80.85-81.60). Graves' disease (GD) was the most common type of thyroid autoimmunity (69.16%, 95% CI: 68.23-70.07). Globally, overt PolyA was found in 13.46% of the patients with AITD. This type of PolyA was represented mainly by type 1 diabetes and autoimmune gastritis. Latent PolyA was presented in 17.45% of the patients, and anti-proinsulin, anti-parietal cells and dsDNA antibodies were the most common. HT had the highest frequency of overt PolyA in Europe (15.60%, 95% CI: 14.72-16.53), whereas latent PolyA was most common in patients with GD in Asia (21.03%, 95% CI: 17.76-24.71). Overt and latent PolyA were associated with gastrointestinal and endocrinological ADs in most of cases and clustered with rheumatological, dermatological and neurological ADs.

CONCLUSIONS

Latent and overt PolyA are common in patients with AITD. These results provide insightful information for early diagnosis and management of concurrent ADs in patients with AITD. Aggregation of ADs in different clusters may help to define different phenotypes associated with thyroid autoimmunity that are critically relevant in clinical settings.

Cross-sectional analysis of trace element status in thyroid disease

BACKGROUND

The synthesis of thyroid hormone depends on a set of trace elements, most importantly selenium and iodine. The dietary supply with certain micronutrients is limited in many areas of the world, including central Europe and large parts of Asia and Africa. Moreover, both thyroid disease risk and therapy effects are modulated by trace element supply and status.

OBJECTIVE

Assessment of trace element status in thyroid patients in a European metropolis.

MATERIAL AND METHODS

Adult patients visiting a medical praxis in Berlin, Germany, were enrolled into a cross-sectional analysis, and serum samples were obtained from thyroid patients (n = 323) with different conditions including goitre, hypothyroidism, malignancy or autoimmune thyroid disease. Trace elements (iodine, selenium, copper and zinc) were assessed by ICP-MS/MS or total reflection X-ray analysis, along with two protein biomarkers of selenium status (selenoprotein P, glutathione peroxidase), and compared to the clinical phenotype.

RESULTS

The patients displayed relatively low serum zinc and selenium concentrations as compared to a set (n = 200) of healthy subjects (zinc; 1025+/-233 vs. 1068+/-230 μg/L, p < 0.01, selenium; 76.9+/18.8 vs. 85.1+/-17.4 μg/L, p < 0.0001). A high fraction of patients (37.5%) was classified as selenium-deficient (serum selenium concentrations <70 μg/L), in particular the patients with thyroid malignancy (59%). Serum copper was not different between the groups, and total serum iodine concentrations were unrelated to thyroid disease. Explorative statistical analyses yielded no significant interactions between the trace elements and disease parameters, except for free thyroxine inversely correlating to the copper/selenium ratio.

CONCLUSIONS

In adult thyroid patients, there is no relation of circulating copper, iodine, selenium or zinc concentrations to thyroid hormone. However, a large fraction of German thyroid patients displays a considerable selenium deficit, known to constitute a disease risk potentially impairing convalescence and aggravating autoimmune disease processes. It appears advisable to testing thyroid patients for selenium deficiency, and once diagnosed, an increased supply via dietary counselling or active supplementation should be considered.