Should we screen for risk of type 1 diabetes?

The relationship between GAD65 autoantibody and the risk of T1DM onset

Objectives

Type 1 diabetes mellitus (T1DM) is a well-known autoimmune disease, characterized by β-cell destruction in pancreas islet cells, which results insulin deficiency and subsequent hyperglycemic sequelae. While there is screening for type 2 DM that leads to better glycemic control and outcome, the majority of T1DM patients are diagnosed when much of the pancreatic cells and their function are disturbed. The aim of this article is to present an overview of the effective factors in the positivity of Glutamic acid decarboxylase antibody )GADA( and identifying the high-risk individuals for T1DM.

Methods

We searched English literature available at National Library of Medicine via PubMed, and Google Scholar through December 2020. Finally, 79 papers have been included in the study. Studies were summarized based on the number of positive autoantibodies and onset of T1DM over time and GADA correlation with different variables.

Conclusions

GADA is an easy marker to measure that can be detected many months prior to the clinical presentation and remains positive even after early childhood.

Effect of Socioeconomic Status and Ethnicity on Glycemic Control in Arab and Jewish Youth with Type 1 Diabetes Mellitus

OBJECTIVES

Research and theory suggests that socioeconomic status may affect diabetes control. We investigated the effect of socioeconomic status and ethnicity on glycated hemoglobin (HbA1c) in Arab and Jewish children with type 1 diabetes mellitus in northern Israel.

METHODS

Data were collected from medical records of 80 Arab and 119 Jewish children attending a pediatric diabetes clinic in a tertiary health care center. Multivariate regression analysis was used to assess factors independently affecting HbA1c level.

RESULTS

Mean age was 12.9±4.7 years. Arab families had more children compared to Jewish families (3.7±1.5 versus 2.9±1.2, respectively, P=0.0007). Academic education was significantly less common in Arab families (25% versus 66.2%, respectively, P=0.0001). Income of Jewish parents was significantly higher compared to that of Arab parents (7,868±2,018 versus 5,129±906 NIS/month, respectively, P=0.0001). Mean age at diagnosis of diabetes was 9.6±4.6 years and disease duration was 3.4±2.3 years in both groups. Half of Arab and Jewish children were treated with multiple insulin injections and half with insulin pumps. Mean number of self-glucose testing/day was higher in Jewish children than in Arab children (4.7±2.5 versus 4.0±1.5, respectively, P=0.033). Mean HbA1c was above recommendations, 9.5% (12.6 mmol/L) in Arab children and 8.7% (11.3 mmol/L) in Jewish children (P=0.004). In multivariate analysis, disease duration (P=0.010) and ethnicity (P=0.034 for Arabs versus Jews) were independently associated with HbA1c.

CONCLUSIONS

Both Arab and Jewish children failed to meet HbA1c goals, but this effect was significantly greater for Arabs. Ethnicity remained a predictor of failure even following adjustment for potential confounders.

Systematic Review: Early Infant Feeding and the Risk of Type 1 Diabetes

BACKGROUND

In addition to genetic background, a number of environmental factors have been claimed to influence the development of type 1 diabetes (T1D), including infant diet.

OBJECTIVE

The aim of the study was to systematically update evidence on the possible relation between early feeding practices and the risk of T1D.

METHODS

The Cochrane Library, MEDLINE, EMBASE, Web of Science, and CINAHL were searched for studies of any design up to July 2015. MEDLINE and EMBASE were additionally searched in March 2016. The primary outcome measures were the development of T1D or T1D-associated autoimmunity (T1DA).

RESULTS

Nine publications were identified. Breastfeeding at the time of gluten introduction, as compared to gluten introduction after weaning, did not reduce the risk of developing T1DA or T1D. In children at high risk of developing T1D, except for gluten introduction at 3 months or younger age compared with gluten introduction at older than 3 months, which increased the risk of T1DA, the age of gluten introduction in infants had no effect on the risk of developing T1DA.

CONCLUSIONS

Current evidence, mainly from observational studies, does not support the claim that early infant feeding practices, such as breastfeeding at gluten introduction or the age of the infant at the time of gluten introduction, may decrease the risk of developing T1D. More robust data are needed from randomized controlled trials.

High Risk First Degree Relatives of Type 1 Diabetics: An Association with Increases in CXCR3(+) T Memory Cells Reflecting an Enhanced Activity of Th1 Autoimmune Response

We analyzed the level of (a) CXCR3(+) (Th1) and CCR4(+) (Th2) T memory cells (b) interferon- γ inducible chemokine (IP-10)(Th1) and thymus and activation-regulated chemokine (TARC)(Th2), in 51 first degree relatives (FDRs) of type 1 diabetics (T1D) (17 high risk FDRs (GADA(+), IA-2(+)) and 34 low risk FDRs (GADA(-), IA-2(-))), 24 recent-onset T1D (R-T1D), and 18 healthy subjects. T memory subsets were analyzed by using four-color immunofluorescence staining and flowcytometry. IP-10 and TARC were determined by ELISA. High risk FDRs showed higher levels of CXCR3(+) and lower level of CCR4(+) T memory cells compared to low risk FDRs (64.98 ± 5.19 versus 42.13 ± 11.11; 29.46 ± 2.83 versus 41.90 ± 8.58%, resp., P < 0.001). Simultaneously, both IP-10 and TARC levels were increased in high risk versus low risk FDRs (160.12 ± 73.40 versus 105.39 ± 71.30; 438.83 ± 120.62 versus 312.04 ± 151.14 pg/mL, P < 0.05). Binary logistic regression analysis identified the level of CXCR3(+) T memory cells as predictors for high risk FDRs, together with high levels of IP-10. The results imply that, in FDRs, the risk for T1D might be strongly influenced by enhanced activity of Th1 and diminished activity of Th2 autoimmune response.

Current evidence on the associations of breastfeeding, infant formula, and cow's milk introduction with type 1 diabetes mellitus: a systematic review

Current evidence provides contradictory results in regards to the associations of breastfeeding or early introduction of cow's milk and formula with the development of type 1 diabetes (T1D). The aim of this systematic review was to evaluate the type of feeding, duration of breastfeeding, time of introduction of formula or cow's milk, and the potential impact on developing T1D. The literature search was conducted based on the standards outlined in the MOOSE Guidelines for Meta-Analyses and Systematic Reviews of Observational Studies and yielded a total of 161 studies, 28 of which were included in this review. Twenty seven of the included studies were case-control and one was a prospective cohort study. Eight of the studies indicated breastfeeding has a protective role against the development of T1D. Seven additional studies emphasized that a short period or absence of breastfeeding could be a risk factor for T1D development. The results of this systematic review indicate a short duration and/or a lack of breastfeeding may constitute a risk factor for the development of T1D later in life.

Immunotherapies in diabetes mellitus type 1

Type 1 diabetes is an autoimmune disease that gradually destructs insulin-producing beta cells. Over the years, clinicians' knowledge regarding the immunopathogenesis of this disease has greatly increased. Immunotherapies that can change the course of immune-mediated destruction and preserve and possibly regenerate the pancreatic beta cells seem to be promising in preclinical trials but so far have been unsuccessful in human studies. This article reviews the important immune interventions for type 1 diabetes that have been tried so far targeting the different stages of disease development and provides an insight into what the future might hold.

Validation of the Diabetes Prevention Trial-Type 1 Risk Score in the TrialNet Natural History Study

OBJECTIVE

We assessed the accuracy of the Diabetes Prevention Trial-Type 1 Risk Score (DPTRS), developed from the Diabetes Prevention Trial-Type 1 (DPT-1), in the TrialNet Natural History Study (TNNHS).

RESEARCH DESIGN AND METHODS

Prediction accuracy of the DPTRS was assessed with receiver-operating characteristic curve areas. The type 1 diabetes cumulative incidence within the DPTRS intervals was compared between the TNNHS and DPT-1 cohorts.

RESULTS

Receiver-operating characteristic curve areas for the DPTRS were substantial in the TNNHS (P < 0.001 at both 2 and 3 years). The type 1 diabetes cumulative incidence did not differ significantly between the TNNHS and DPT-1 cohorts within DPTRS intervals. In the TNNHS, 2-year and 3-year risks were low for DPTRS intervals <6.50 (<0.10 and <0.20, respectively). Thresholds ≥7.50 were indicative of high risk in both cohorts (2-year risks: 0.49 in the TNNHS and 0.51 in DPT-1).

CONCLUSIONS

The DPTRS is an accurate and robust predictor of type 1 diabetes in autoantibody-positive populations.

Dietary intervention in infancy and later signs of beta-cell autoimmunity

BACKGROUND

Early exposure to complex dietary proteins may increase the risk of beta-cell autoimmunity and type 1 diabetes in children with genetic susceptibility. We tested the hypothesis that supplementing breast milk with highly hydrolyzed milk formula would decrease the cumulative incidence of diabetes-associated autoantibodies in such children.

METHODS

In this double-blind, randomized trial, we assigned 230 infants with HLA-conferred susceptibility to type 1 diabetes and at least one family member with type 1 diabetes to receive either a casein hydrolysate formula or a conventional, cow's-milk-based formula (control) whenever breast milk was not available during the first 6 to 8 months of life. Autoantibodies to insulin, glutamic acid decarboxylase (GAD), the insulinoma-associated 2 molecule (IA-2), and zinc transporter 8 were analyzed with the use of radiobinding assays, and islet-cell antibodies were analyzed with the use of immunofluorescence, during a median observation period of 10 years (mean, 7.5). The children were monitored for incident type 1 diabetes until they were 10 years of age.

RESULTS

The unadjusted hazard ratio for positivity for one or more autoantibodies in the casein hydrolysate group, as compared with the control group, was 0.54 (95% confidence interval [CI], 0.29 to 0.95), and the hazard ratio adjusted for an observed difference in the duration of exposure to the study formula was 0.51 (95% CI, 0.28 to 0.91). The unadjusted hazard ratio for positivity for two or more autoantibodies was 0.52 (95% CI, 0.21 to 1.17), and the adjusted hazard ratio was 0.47 (95% CI, 0.19 to 1.07). The rate of reported adverse events was similar in the two groups.

CONCLUSIONS

Dietary intervention during infancy appears to have a long-lasting effect on markers of beta-cell autoimmunity--markers that may reflect an autoimmune process leading to type 1 diabetes. (ClinicalTrials.gov number, NCT00570102.).