Tissue transglutaminase autoantibodies in children with newly diagnosed type 1 diabetes are related to human leukocyte antigen but not to islet autoantibodies: A Swedish nationwide prospective population-based cohort study

Prevalence of latent and overt polyautoimmunity in type 1 diabetes: A systematic review and meta-analysis

BACKGROUND

Patients afflicted by type 1 diabetes (T1D) exhibit polyautoimmunity (PolyA). However, the frequency and distribution of PolyA in T1D is still unknown.

OBJECTIVE

We conducted a systematic review and meta-analysis to define the prevalence of latent and overt PolyA in individuals with T1D.

METHODS

Following PRISMA guidelines, a comprehensive search across medical databases identified studies on latent and overt PolyA in T1D. Two researchers independently screened, extracted data, and assessed study quality. A random effects model was utilized to calculate the pooled prevalence, along with its corresponding 95 % confidence interval (CI), for latent PolyA and overt PolyA. Meta-regression analysis was conducted to study the effect of study designs, age, sex, and duration of disease on pooled prevalence.

RESULTS

A total of 158 articles, encompassing a diverse composition of study designs were scrutinized. The analysis included 270,890 individuals with a confirmed diagnosis of T1D. The gender was evenly distributed (50.30 % male). Notably, our analysis unveiled an overt PolyA prevalence rate of 8.50 % (95 % CI, 6.77 to 10.62), with North America having the highest rates (14.50 %, 95 % CI, 7.58 to 24.89). This PolyA profile was further characterized by a substantial incidence of concurrent autoimmune thyroid disease (7.44 %, 95 % CI, 5.65 to 9.74). Moreover, we identified a notable prevalence of latent PolyA in the T1D population, quantified at 14.45 % (95 % CI, 11.17 to 18.49) being most frequent in Asia (23.29 %, 95 % CI, 16.29 to 32.15) and Oceania (21.53 %, 95 % CI, 16.48 to 27.62). Remarkably, this latent PolyA phenomenon primarily featured an array of autoantibodies, including rheumatoid factor, followed by Ro52, thyroid peroxidase antibodies, and thyroglobulin antibodies. Duration of the disease was associated with a highest frequency of latent (β: 0.0456, P-value: 0.0140) and overt PolyA (β: 0.0373, P-value: 0.0152). No difference in the pooled prevalence by study design was observed.

CONCLUSION

This meta-analysis constitutes a substantial advancement in the realm of early detection of PolyA in the context of T1D. Individuals with T1D should regularly undergo assessments to identify potential concurrent autoimmune diseases, especially as they age.

Do sex differences in paediatric type 1 diabetes care exist? A systematic review

AIMS/HYPOTHESIS

Sex differences are present in cardiovascular care and in outcomes among adults with type 1 diabetes mellitus, which typically commences in childhood. Whether sex influences care and outcomes in childhood is not known. This systematic review provides an overview of sex differences in children with type 1 diabetes, focusing on patient and disease characteristics, treatment, comorbidities and complications.

METHODS

Literature in MEDLINE up to 15 June 2021 was searched, using the terms diabetes mellitus, sex characteristics, sex distribution, children and/or adolescents. All primary outcome studies on children with type 1 diabetes that mentioned a sex difference in outcome were included, with the exception of qualitative studies, case reports or case series. Studies not pertaining to the regular clinical care process and on incidence or prevalence only were excluded. Articles reporting sex differences were identified and assessed on quality and risk of bias using Joanna Briggs Institute critical appraisal tools. Narrative synthesis and an adapted Harvest plot were used to summarise evidence by category.

RESULTS

A total of 8640 articles were identified, rendering 90 studies for review (n=643,217 individuals). Studies were of observational design and comprised cohort, cross-sectional and case-control studies. Most of the included studies showed a higher HbA_1c in young female children both at diagnosis (seven studies, n=22,089) and during treatment (20 out of 21 studies, n=144,613), as well as a steeper HbA_1c increase over time. Many studies observed a higher BMI (all ages, ten studies, n=89,700; adolescence, seven studies, n=33,153), a higher prevalence of being overweight or obese, and a higher prevalence of dyslipidaemia among the female sex. Hypoglycaemia and partial remission occurred more often in male participants, and ketoacidosis (at diagnosis, eight studies, n=3561) and hospitalisation was more often seen in female participants. Most of the findings showed that female participants used pump therapy more frequently (six studies, n=211,324) and needed higher insulin doses than male participants. Several comorbidities, such as thyroid disease and coeliac disease, appeared to be more common in female participants. All studies reported lower quality of life in female participants (15 studies, n=8722). Because the aim of this study was to identify sex differences, studies with neutral outcomes or minor differences may have been under-targeted. The observational designs of the included studies also limit conclusions on the causality between sex and clinical outcomes.

CONCLUSIONS/INTERPRETATION

Sex disparities were observed throughout diabetes care in children with type 1 diabetes. Several outcomes appear worse in young female children, especially during adolescence. Focus on the cause and treatment of these differences may provide opportunities for better outcomes.

REGISTRATION

This systematic review is registered in PROSPERO (CRD42020213640).

Celiac disease can be predicted by high levels of tissue transglutaminase antibodies in children and adolescents with type 1 diabetes

OBJECTIVES

Children with type 1 diabetes (T1D) are not included in guidelines regarding diagnosis criteria for celiac disease (CD) without a diagnostic biopsy, due to lack of data. We explored whether tissue transglutaminase antibodies (anti-tTG) that were ≥ 10 times the upper limit of normal (10× ULN) predicted CD in T1D.

METHODS

Data from the Swedish prospective Better Diabetes Diagnosis study was used, and 2035 children and adolescents with T1D diagnosed between 2005-2010 were included. Of these, 32 had been diagnosed with CD before T1D. The children without CD were repeatedly screened for CD using anti-tTG antibodies of immunoglobulin type A. In addition, their human leukocyte antigen (HLA) were genotyped. All children with positive anti-tTG were advised to undergo biopsy. Biopsies were performed on 119 children and graded using the Marsh-Oberhüber classification.

RESULTS

All of the 60 children with anti-tTG ≥10x ULN had CD verified by biopsies. The degree of mucosal damage correlated with anti-tTG levels. Among 2003 screened children, 6.9% had positive anti-tTG and 5.6% were confirmed CD. The overall CD prevalence, when including the 32 children with CD before T1D, was 7.0% (145/2035). All but one of the children diagnosed with CD had HLA-DQ2 and/or DQ8.

CONCLUSIONS

As all screened children and adolescents with T1D with tissue transglutaminase antibodies above 10 times the positive value 10x ULN had CD, we propose that the guidelines for diagnosing CD in screened children, when biopsies can be omitted, should also apply to children and adolescents with T1D as a noninvasive method.

Increasing Co-occurrence of Additional Autoimmune Disorders at Diabetes Type 1 Onset Among Children and Adolescents Diagnosed in Years 2010-2018-Single-Center Study

Objectives: The prevalence of type 1 diabetes mellitus (T1D) in children is growing, but its relation to other autoimmune disorders that coexist since the onset of diabetes is not recognized. The objective of this study was to assess the incidence of T1D and the prevalence of autoimmune illnesses additionally coexisting since the diabetes mellitus onset in children during a period of 9 years' observation. Methods: In this retrospective study, the incidence rate (IR) of the T1D was calculated as the total number of all cases that were newly diagnosed per 100,000 population people between 0 and 18 years of age. The selected age groups (0-4, 5-9, 10-14, and 15-18 years) were examined, respectively. The studied group included 493 children (264 [53.55%] boys) between 0 and 18 years old newly diagnosed with T1D in one of the Polish centers in the years 2010-2018. Other autoimmune illnesses diagnoses were obtained from medical records taken from the first hospital treatment, when T1D was recognized. Results: The annual standardized IR of T1D increased from 19.2/100,000 in year 2010 to 31.7/100,000 in 2018 (1.7-fold over 9 years' observation), with an increase in the incidence rate ratio (IRR) by 4% per year. The highest growth in IR was recorded in 5- to 9-year-olds (from 19.61 in 2010 to 43.45 in 2018). In 61 (12.4%) of the studied group, at least one additional autoimmune disease was diagnosed. The prevalence doubled from 10.4% in the year 2010 to 20.8% in the year 2018. Autoimmune thyroid illnesses were found in 37 children (7.5%); their incidence increased from 6.3% to almost 2-fold, 12.5%, in 2018. In 26 children (5.3%), celiac disease was recognized; the prevalence increased from 4.2 to 9.8% in the study period. The prevalence of additional autoimmune thyroid disease was higher in glutamic acid decarboxylase-positive antibodies (χ² = 3.4, p = 0.04) patients, the oldest age group (15-18 years) (χ² =7.1, p = 0.06), and in girls (χ² =7.1, p = 0.007). Conclusions:The standardized IR of T1D in children increased 1.7-fold over the 9-year observation period, and IRR increased 4% per year. Additional autoimmunity represents a significant comorbidity in patients with new-onset T1D. The number of children diagnosed with additional autoimmune diseases that accompany T1D is rapidly growing in all age groups throughout recent years.