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1.
Diabetologia ; 64(4): 836-844, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33496819

RESUMO

AIMS/HYPOTHESIS: We aimed to compare characteristics of individuals identified in the peri-diagnostic range by Index60 (composite glucose and C-peptide measure) ≥2.00, 2 h OGTT glucose ≥11.1 mmol/l, or both. METHODS: We studied autoantibody-positive participants in the Type 1 Diabetes TrialNet Pathway to Prevention study who, at their baseline OGTT, had 2 h blood glucose ≥11.1 mmol/l and/or Index60 ≥2.00 (n = 354, median age = 11.2 years, age range = 1.7-46.6; 49% male, 83% non-Hispanic White). Type 1 diabetes-relevant characteristics (e.g., age, C-peptide, autoantibodies, BMI) were compared among three mutually exclusive groups: 2 h glucose ≥11.1 mmol/l and Index60 <2.00 [Glu(+), n = 76], 2 h glucose <11.1 mmol/l and Index60 ≥2.00 [Ind(+), n = 113], or both 2 h glucose ≥11.1 mmol/l and Index60 ≥2.00 [Glu(+)/Ind(+), n = 165]. RESULTS: Participants in Glu(+), vs those in Ind(+) or Glu(+)/Ind(+), were older (mean ages = 22.9, 11.8 and 14.7 years, respectively), had higher early (30-0 min) C-peptide response (1.0, 0.50 and 0.43 nmol/l), higher AUC C-peptide (2.33, 1.13 and 1.10 nmol/l), higher percentage of overweight/obesity (58%, 16% and 30%) (all comparisons, p < 0.0001), and a lower percentage of multiple autoantibody positivity (72%, 92% and 93%) (p < 0.001). OGTT-stimulated C-peptide and glucose patterns of Glu(+) differed appreciably from Ind(+) and Glu(+)/Ind(+). Progression to diabetes occurred in 61% (46/76) of Glu(+) and 63% (71/113) of Ind(+). Even though Index60 ≥2.00 was not a Pathway to Prevention diagnostic criterion, Ind(+) had a 4 year cumulative diabetes incidence of 95% (95% CI 86%, 98%). CONCLUSIONS/INTERPRETATION: Participants in the Ind(+) group had more typical characteristics of type 1 diabetes than participants in the Glu(+) did and were as likely to be diagnosed. However, unlike Glu(+) participants, Ind(+) participants were not identified at the baseline OGTT.


Assuntos
Glicemia/metabolismo , Peptídeo C/sangue , Técnicas de Apoio para a Decisão , Diabetes Mellitus Tipo 1/diagnóstico , Teste de Tolerância a Glucose , Ilhotas Pancreáticas/metabolismo , Adolescente , Adulto , Autoanticorpos/sangue , Biomarcadores/sangue , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/imunologia , Progressão da Doença , Diagnóstico Precoce , Feminino , Humanos , Lactente , Ilhotas Pancreáticas/imunologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Adulto Jovem
2.
Diabetes Obes Metab ; 22(6): 997-1000, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32003110

RESUMO

We examined whether the timing of the C-peptide response during an oral glucose tolerance test (OGTT) in relatives of patients with type 1 diabetes (T1D) is predictive of disease onset. We examined baseline 2-h OGTTs from 670 relatives participating in the Diabetes Prevention Trial-Type 1 (age: 13.8 ± 9.6 years; body mass index z-score: 0.3 ± 1.1; 56% male) using univariate regression models. T1D risk increased with lower early C-peptide responses (30-0 min) (χ2 = 28.8, P < 0.001), and higher late C-peptide responses (120-60 min) (χ2 = 23.3, P < 0.001). When both responses were included in a proportional hazards model, they remained independently and oppositely associated with T1D, with a stronger overall association for the combined model than either response alone (χ2 = 41.1; P < 0.001). Using receiver operating characteristic curve analysis, the combined early and late C-peptide response was more accurately predictive of T1D than area under the curve C-peptide (P = 0.005). Our findings demonstrate that lower early and higher late C-peptide responses serve as indicators of increased T1D risk.


Assuntos
Autoanticorpos , Peptídeo C , Diabetes Mellitus Tipo 1 , Teste de Tolerância a Glucose , Adolescente , Adulto , Glicemia , Peptídeo C/metabolismo , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/diagnóstico , Feminino , Humanos , Masculino , Curva ROC , Adulto Jovem
3.
Pediatr Diabetes ; 20(4): 408-413, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30891858

RESUMO

BACKGROUND: In new onset type 1 diabetes (T1D), overall C-peptide measures such as area under the curve (AUC) C-peptide and peak C-peptide are useful for estimating the extent of ß-cell dysfunction, and for assessing responses to intervention therapy. However, measures of the timing of C-peptide responsiveness could have additional value. OBJECTIVES: We assessed the contribution of the timing of C-peptide responsiveness during oral glucose tolerance tests (OGTTs) to hemoglobin A1c (HbA1c) variation at T1D diagnosis. METHODS: We analyzed data from 85 individuals <18 years with OGTTs and HbA1c measurements at diagnosis. Overall [AUC and peak C-peptide] and timing measures [30-0 minute C-peptide (early); 60 to 120 minute C-peptide sum-30 minutes (late); 120/30 C-peptide; time to peak C-peptide] were utilized. RESULTS: At diagnosis, the mean (±SD) age was 11.2 ± 3.3 years, body mass index (BMI)-z was 0.4 ± 1.1, 51.0% were male. The average HbA1c was 43.54 ± 8.46 mmol/mol (6.1 ± 0.8%). HbA1c correlated inversely with the AUC C-peptide (P < 0.001), peak C-peptide (P < 0.001), early and late C-peptide responses (P < 0.001 each), and 120/30 C-peptide (P < 0.001). Those with a peak C-peptide occurring at ≤60 minutes had higher HbA1c values than those with peaks later (P = 0.003). HbA1c variance was better explained with timing measures added to regression models (R2 = 11.6% with AUC C-peptide alone; R2 = 20.0% with 120/30 C-peptide added; R2 = 13.7% with peak C-peptide alone, R2 = 20.4% with timing of the peak added). Similar associations were seen between the 2-hour glucose and the C-peptide measures. CONCLUSIONS: These findings show that the addition of timing measures of C-peptide responsiveness better explains HbA1c variation at diagnosis than standard measures alone.


Assuntos
Peptídeo C/metabolismo , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/genética , Hemoglobinas Glicadas/metabolismo , Adolescente , Adulto , Glicemia/genética , Glicemia/metabolismo , Peptídeo C/análise , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Feminino , Estudos de Associação Genética , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/análise , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
4.
Diabetologia ; 61(1): 84-92, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28956083

RESUMO

AIMS/HYPOTHESIS: We aimed to examine: (1) whether specific glucose-response curve shapes during OGTTs are predictive of type 1 diabetes development; and (2) the extent to which the glucose-response curve is influenced by insulin secretion. METHODS: Autoantibody-positive relatives of people with type 1 diabetes whose baseline OGTT met the definition of a monophasic or biphasic glucose-response curve were followed for the development of type 1 diabetes (n = 2627). A monophasic curve was defined as an increase in OGTT glucose between 30 and 90 min followed by a decline of ≥ 0.25 mmol/l between 90 and 120 min. A biphasic response curve was defined as a decrease in glucose after an initial increase, followed by a second increase of ≥ 0.25 mmol/l. Associations of type 1 diabetes risk with glucose curve shapes were examined using cumulative incidence curve comparisons and proportional hazards regression. C-peptide responses were compared with and without adjustments for potential confounders. RESULTS: The majority of participants had a monophasic curve at baseline (n = 1732 [66%] vs n = 895 [34%]). The biphasic group had a lower cumulative incidence of type 1 diabetes (p < 0.001), which persisted after adjustments for age, sex, BMI z score and number of autoantibodies (p < 0.001). Among the monophasic group, the risk of type 1 diabetes was greater for those with a glucose peak at 90 min than for those with a peak at 30 min; the difference persisted after adjustments (p < 0.001). Compared with the biphasic group, the monophasic group had a lower early C-peptide (30-0 min) response, a lower C-peptide index (30-0 min C-peptide/30-0 min glucose), as well as a greater 2 h C-peptide level (p < 0.001 for all). CONCLUSIONS/INTERPRETATION: Those with biphasic glucose curves have a lower risk of progression to type 1 diabetes than those with monophasic curves, and the risk among the monophasic group is increased when the glucose peak occurs at 90 min than at 30 min. Differences in glucose curve shapes between the monophasic and biphasic groups appear to be related to C-peptide responses.


Assuntos
Peptídeo C/metabolismo , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/metabolismo , Teste de Tolerância a Glucose/métodos , Adulto , Glicemia/metabolismo , Feminino , Humanos , Insulina/metabolismo , Masculino , Pessoa de Meia-Idade
5.
Pediatr Diabetes ; 19(3): 403-409, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29171129

RESUMO

BACKGROUND/OBJECTIVE: The extent of influence of BMI and age on C-peptide at the diagnosis of type 1 diabetes (T1D) is unknown. We thus studied the impact of body mass index Z-scores (BMIZ) and age on C-peptide measures at and soon after the diagnosis of T1D. METHODS: Data from Diabetes Prevention Trial-Type 1 (DPT-1) participants <18.0 years at diagnosis was analyzed. Analyses examined associations of C-peptide measures with BMIZ and age in 2 cohorts: oral glucose tolerance tests (OGTTs) at diagnosis (n = 99) and mixed meal tolerance tests (MMTTs) <6 months after diagnosis (n = 80). Multivariable linear regression was utilized. RESULTS: Fasting and area under the curve (AUC) C-peptide from OGTTs (n = 99) at diagnosis and MMTTs (n = 80) after diagnosis were positively associated with BMIZ and age (P < .001 for all). Associations persisted when BMIZ and age were included as independent variables in regression models (P < .001 for all). BMIZ and age explained 31%-47% of the variance of C-peptide measures. In an example, 2 individuals with identical AUC C-peptide values had an approximate 5-fold difference in values after adjustments for BMIZ and age. The association between fasting glucose and C-peptide decreased markedly when fasting C-peptide values were adjusted (r = 0.30, P < .01 to r = 0.07, n.s.). CONCLUSIONS: C-peptide measures are strongly and independently related to BMIZ and age at and soon after the diagnosis of T1D. Adjustments for BMIZ and age cause substantial changes in C-peptide values, and impact the association between glycemia and C-peptide. Such adjustments can improve assessments of ß-cell impairment at diagnosis.


Assuntos
Peptídeo C/sangue , Diabetes Mellitus Tipo 1/sangue , Adolescente , Fatores Etários , Índice de Massa Corporal , Criança , Diabetes Mellitus Tipo 1/diagnóstico , Feminino , Humanos , Masculino
6.
JAMA ; 319(1): 38-48, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29297078

RESUMO

Importance: Early exposure to complex dietary proteins may increase the risk of type 1 diabetes in children with genetic disease susceptibility. There are no intact proteins in extensively hydrolyzed formulas. Objective: To test the hypothesis that weaning to an extensively hydrolyzed formula decreases the cumulative incidence of type 1 diabetes in young children. Design, Setting, and Participants: An international double-blind randomized clinical trial of 2159 infants with human leukocyte antigen-conferred disease susceptibility and a first-degree relative with type 1 diabetes recruited from May 2002 to January 2007 in 78 study centers in 15 countries; 1081 were randomized to be weaned to the extensively hydrolyzed casein formula and 1078 to a conventional formula. The follow-up of the participants ended on February 28, 2017. Interventions: The participants received either a casein hydrolysate or a conventional adapted cow's milk formula supplemented with 20% of the casein hydrolysate. The minimum duration of study formula exposure was 60 days by 6 to 8 months of age. Main Outcomes and Measures: Primary outcome was type 1 diabetes diagnosed according to World Health Organization criteria. Secondary outcomes included age at diabetes diagnosis and safety (adverse events). Results: Among 2159 newborn infants (1021 female [47.3%]) who were randomized, 1744 (80.8%) completed the trial. The participants were observed for a median of 11.5 years (quartile [Q] 1-Q3, 10.2-12.8). The absolute risk of type 1 diabetes was 8.4% among those randomized to the casein hydrolysate (n = 91) vs 7.6% among those randomized to the conventional formula (n = 82) (difference, 0.8% [95% CI, -1.6% to 3.2%]). The hazard ratio for type 1 diabetes adjusted for human leukocyte antigen risk group, duration of breastfeeding, duration of study formula consumption, sex, and region while treating study center as a random effect was 1.1 (95% CI, 0.8 to 1.5; P = .46). The median age at diagnosis of type 1 diabetes was similar in the 2 groups (6.0 years [Q1-Q3, 3.1-8.9] vs 5.8 years [Q1-Q3, 2.6-9.1]; difference, 0.2 years [95% CI, -0.9 to 1.2]). Upper respiratory infections were the most common adverse event reported (frequency, 0.48 events/year in the hydrolysate group and 0.50 events/year in the control group). Conclusions and Relevance: Among infants at risk for type 1 diabetes, weaning to a hydrolyzed formula compared with a conventional formula did not reduce the cumulative incidence of type 1 diabetes after median follow-up for 11.5 years. These findings do not support a need to revise the dietary recommendations for infants at risk for type 1 diabetes. Trial Registration: clinicaltrials.gov Identifier: NCT00179777.


Assuntos
Caseínas , Diabetes Mellitus Tipo 1/prevenção & controle , Fórmulas Infantis , Criança , Diabetes Mellitus Tipo 1/epidemiologia , Intervalo Livre de Doença , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Masculino , Política Nutricional , Risco
7.
Diabetologia ; 60(1): 43-49, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27704166

RESUMO

AIMS/HYPOTHESIS: GAD is a major target of the autoimmune response that occurs in type 1 diabetes mellitus. Randomised controlled clinical trials of a GAD + alum vaccine in human participants have so far given conflicting results. METHODS: In this study, we sought to see whether a clearer answer to the question of whether GAD65 has an effect on C-peptide could be reached by combining individual-level data from the randomised controlled trials using Bayesian meta-analysis to estimate the probability of a positive biological effect (a reduction in C-peptide loss compared with placebo approximately 1 year after the GAD vaccine). RESULTS: We estimate that there is a 98% probability that 20 µg GAD with alum administered twice yields a positive biological effect. The effect is probably a 15-20% reduction in the loss of C-peptide at approximately 1 year after treatment. This translates to an annual expected loss of between -0.250 and -0.235 pmol/ml in treated patients compared with an expected 2 h AUC loss of -0.294 pmol/ml at 1 year for untreated newly diagnosed patients. CONCLUSIONS/INTERPRETATION: The biological effect of this vaccination should be developed further in order to reach clinically desirable reductions in insulin loss in patients recently diagnosed with type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Glutamato Descarboxilase/imunologia , Insulina/metabolismo , Vacinas/imunologia , Adolescente , Adulto , Teorema de Bayes , Criança , Diabetes Mellitus Tipo 1/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Diabetologia ; 59(1): 13-20, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26498592

RESUMO

Diabetes is not a single homogeneous disease but composed of many diseases with hyperglycaemia as a common feature. Four factors have, historically, been used to identify this diversity: the age at onset; the severity of the disease, i.e. degree of loss of beta cell function; the degree of insulin resistance and the presence of diabetes-associated autoantibodies. Our broad understanding of the distinction between the two major types, type 1 diabetes mellitus and type 2 diabetes mellitus, are based on these factors, but it has become apparent that they do not precisely capture the different disease forms. Indeed, both major types of diabetes have common features, encapsulated by adult-onset autoimmune diabetes and maturity-onset diabetes of the young. As a result, there has been a repositioning of our understanding of diabetes. In this review, drawing on recent literature, we discuss the evidence that autoimmune type 1 diabetes has a broad clinical phenotype with diverse therapeutic options, while the term non-autoimmune type 2 diabetes obscures the optimal management strategy because it encompasses substantial heterogeneity. Underlying these developments is a general progression towards precision medicine with the need for precise patient characterisation, currently based on clinical phenotypes but in future augmented by laboratory-based tests.


Assuntos
Diabetes Mellitus/diagnóstico , Diabetes Mellitus/fisiopatologia , Diabetes Mellitus/terapia , Fatores Etários , Alelos , Autoanticorpos/sangue , Autoimunidade , Peptídeo C/sangue , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/terapia , Progressão da Doença , Genótipo , Humanos , Hiperglicemia/sangue , Insulina/metabolismo , Resistência à Insulina , Fenótipo
9.
N Engl J Med ; 366(5): 433-42, 2012 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-22296077

RESUMO

BACKGROUND: The 65-kD isoform of glutamic acid decarboxylase (GAD65) is a major autoantigen in type 1 diabetes. We hypothesized that alum-formulated GAD65 (GAD-alum) can preserve beta-cell function in patients with recent-onset type 1 diabetes. METHODS: We studied 334 patients, 10 to 20 years of age, with type 1 diabetes, fasting C-peptide levels of more than 0.3 ng per milliliter (0.1 nmol per liter), and detectable serum GAD65 autoantibodies. Within 3 months after diagnosis, patients were randomly assigned to receive one of three study treatments: four doses of GAD-alum, two doses of GAD-alum followed by two doses of placebo, or four doses of placebo. The primary outcome was the change in the stimulated serum C-peptide level (after a mixed-meal tolerance test) between the baseline visit and the 15-month visit. Secondary outcomes included the glycated hemoglobin level, mean daily insulin dose, rate of hypoglycemia, and fasting and maximum stimulated C-peptide levels. RESULTS: The stimulated C-peptide level declined to a similar degree in all study groups, and the primary outcome at 15 months did not differ significantly between the combined active-drug groups and the placebo group (P=0.10). The use of GAD-alum as compared with placebo did not affect the insulin dose, glycated hemoglobin level, or hypoglycemia rate. Adverse events were infrequent and mild in the three groups, with no significant differences. CONCLUSIONS: Treatment with GAD-alum did not significantly reduce the loss of stimulated C peptide or improve clinical outcomes over a 15-month period. (Funded by Diamyd Medical and the Swedish Child Diabetes Foundation; ClinicalTrials.gov number, NCT00723411.).


Assuntos
Peptídeo C/sangue , Diabetes Mellitus Tipo 1/tratamento farmacológico , Glutamato Descarboxilase/uso terapêutico , Adolescente , Autoanticorpos/sangue , Criança , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/imunologia , Feminino , Glutamato Descarboxilase/efeitos adversos , Glutamato Descarboxilase/imunologia , Humanos , Masculino , Isoformas de Proteínas , Adulto Jovem
10.
Trends Immunol ; 33(11): 546-53, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22897868

RESUMO

Recent advances in understanding the etiology of obesity, metabolic syndrome, and type 2 diabetes (T2D) have established involvement of the immune system. These developments highlight the potential of immunomodulatory therapies for treatment of these conditions. Here, we discuss current and new immunotherapeutic strategies for the treatment of T2D, the need for stratification of patients based on immune and autoimmune status, and biomarkers for evaluating treatment efficiency. The time has come to re-evaluate the clinical management of T2D patients using metabolic parameters alone, and to realize that patients should be stratified based on their immune and/or autoimmune status prior to initiation of therapy to realize fully the potential of immunomodulatory strategies for T2D.


Assuntos
Diabetes Mellitus Tipo 2/imunologia , Diabetes Mellitus Tipo 2/terapia , Animais , Autoimunidade , Biomarcadores/sangue , Diabetes Mellitus Tipo 2/sangue , Humanos , Imunoterapia
11.
Curr Diab Rep ; 15(8): 49, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26077017

RESUMO

This report details the development, validation, and utility of the Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score (DPTRS) for type 1 diabetes (T1D). Proportional hazards regression was used to develop the DPTRS model which includes the glucose and C-peptide sums from oral glucose tolerance tests at 30, 60, 90, and 120 min, the log fasting C-peptide, age, and the log BMI. The DPTRS was externally validated in the TrialNet Natural History Study cohort (TNNHS). In a study of the application of the DPTRS, the findings showed that it could be used to identify normoglycemic individuals who were at a similar risk for T1D as those with dysglycemia. The DPTRS could also be used to identify lower risk dysglycemic individuals. Risk estimates of individuals deemed to be at higher risk according to DPTRS values did not differ significantly between the DPT-1 and the TNNHS; whereas, the risk estimates for those with dysglycemia were significantly higher in DPT-1. Individuals with very high DPTRS values were found to be at such marked risk for T1D that they could reasonably be considered to be in a pre-diabetic state. The findings indicate that the DPTRS has utility in T1D prevention trials and for identifying pre-diabetic individuals.


Assuntos
Diabetes Mellitus Tipo 1/diagnóstico , Autoanticorpos/sangue , Glicemia/análise , Peptídeo C/sangue , Diabetes Mellitus Tipo 1/metabolismo , Humanos , Estado Pré-Diabético , Fatores de Risco
12.
Pediatr Diabetes ; 16(2): 129-37, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23944770

RESUMO

AIMS: Intravenous glucose tolerance testing (IVGTT) is a common test of ß-cell function in which a glucose load is administered and insulin and/or C-peptide responses are monitored. Since the first IVGTT may be more stressful and stress may alter ß-cell secretion or hepatic insulin extraction, we asked whether there was a first test effect. METHODS: Insulin and C-peptide responses were compared from two sequential IVGTTs performed within 6 months during staging for the Diabetes Prevention Trial-Type 1 (DPT-1) in 368 people at high risk for type 1 diabetes. Insulin data (1+3 min) were used because the first phase insulin response (and peak insulin concentration) occurs within this time frame. Areas under the curve (AUC) calculations represent early insulin or C-peptide responses from 0 through 10 min post-glucose challenge. RESULTS: More than half of all subjects were found to have first test values lower than the second. This was true for all measures of both insulin and C-peptide but the frequency was significantly different only for insulin measures corrected for basal and for insulin AUC (p < 0.05). However, for subjects (n = 99) whose 1+3 min insulin response was <10th percentile on the first test, there was a significant increase on the second test (p < 0.05). The C-peptide: insulin ratio did not change significantly between tests, indicating that differences are due to changes in ß-cell secretion rather than hepatic insulin uptake. CONCLUSIONS: A statistically significant first test effect occurs during the IVGTT attributable to variations in insulin secretion rather than hepatic uptake.


Assuntos
Intolerância à Glucose/diagnóstico , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Estresse Psicológico/complicações , Adolescente , Adulto , Peptídeo C/sangue , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/epidemiologia , Saúde da Família , Glucose/administração & dosagem , Glucose/metabolismo , Intolerância à Glucose/sangue , Intolerância à Glucose/complicações , Intolerância à Glucose/metabolismo , Teste de Tolerância a Glucose , Humanos , Infusões Intravenosas , Insulina/sangue , Secreção de Insulina , Fígado/metabolismo , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Risco , Adulto Jovem
13.
JAMA ; 311(22): 2279-87, 2014 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-24915259

RESUMO

IMPORTANCE: The disease process leading to clinical type 1 diabetes often starts during the first years of life. Early exposure to complex dietary proteins may increase the risk of ß-cell autoimmunity in children at genetic risk for type 1 diabetes. Extensively hydrolyzed formulas do not contain intact proteins. OBJECTIVE: To test the hypothesis that weaning to an extensively hydrolyzed formula decreases the cumulative incidence of diabetes-associated autoantibodies in young children. DESIGN, SETTING, AND PARTICIPANTS: A double-blind randomized clinical trial of 2159 infants with HLA-conferred disease susceptibility and a first-degree relative with type 1 diabetes recruited from May 2002 to January 2007 in 78 study centers in 15 countries; 1078 were randomized to be weaned to the extensively hydrolyzed casein formula and 1081 were randomized to be weaned to a conventional cows' milk-based formula. The participants were observed to April 16, 2013. INTERVENTIONS: The participants received either a casein hydrolysate or a conventional cows' milk formula supplemented with 20% of the casein hydrolysate. MAIN OUTCOMES: AND MEASURES: Primary outcome was positivity for at least 2 diabetes-associated autoantibodies out of 4 analyzed. Autoantibodies to insulin, glutamic acid decarboxylase, and the insulinoma-associated-2 (IA-2) molecule were analyzed using radiobinding assays and islet cell antibodies with immunofluorescence during a median observation period of 7.0 years (mean, 6.3 years). RESULTS: The absolute risk of positivity for 2 or more islet autoantibodies was 13.4% among those randomized to the casein hydrolysate formula (n = 139) vs 11.4% among those randomized to the conventional formula (n = 117). The unadjusted hazard ratio for positivity for 2 or more autoantibodies among those randomized to be weaned to the casein hydrolysate was 1.21 (95% CI, 0.94-1.54), compared with those randomized to the conventional formula, while the hazard ratio adjusted for HLA risk, duration of breastfeeding, vitamin D use, study formula duration and consumption, and region was 1.23 (95% CI, 0.96-1.58). There were no clinically significant differences in the rate of reported adverse events between the 2 groups. CONCLUSIONS AND RELEVANCE: Among infants at risk for type 1 diabetes, the use of a hydrolyzed formula, when compared with a conventional formula, did not reduce the incidence of diabetes-associated autoantibodies after 7 years. These findings do not support a benefit from hydrolyzed formula. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00179777.


Assuntos
Autoanticorpos/análise , Autoimunidade , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/imunologia , Fórmulas Infantis , Animais , Aleitamento Materno , Caseínas , Criança , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 1/prevenção & controle , Proteínas Alimentares/imunologia , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Hidrólise , Incidência , Recém-Nascido , Células Secretoras de Insulina , Masculino , Leite/imunologia , Risco , Desmame
14.
J Endocr Soc ; 8(3): bvad179, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38333889

RESUMO

Context: Autoantibodies directed against the 65-kilodalton isoform of glutamic acid decarboxylase (GAD65Abs) are markers of autoimmune type 1 diabetes (T1D) but are also present in patients with Latent Autoimmune Diabetes of Adults and autoimmune neuromuscular diseases, and also in healthy individuals. Phenotypic differences between these conditions are reflected in epitope-specific GAD65Abs and anti-idiotypic antibodies (anti-Id) against GAD65Abs. We previously reported that 7.8% of T2D patients in the GRADE study have GAD65Abs but found that GAD65Ab positivity was not correlated with beta-cell function, glycated hemoglobin (HbA1c), or fasting glucose levels. Context: In this study, we aimed to better characterize islet autoantibodies in this T2D cohort. This is an ancillary study to NCT01794143. Methods: We stringently defined GAD65Ab positivity with a competition assay, analyzed GAD65Ab-specific epitopes, and measured GAD65Ab-specific anti-Id in serum. Results: Competition assays confirmed that 5.9% of the patients were GAD65Ab positive, but beta-cell function was not associated with GAD65Ab positivity, GAD65Ab epitope specificity or GAD65Ab-specific anti-Id. GAD65-related autoantibody responses in GRADE T2D patients resemble profiles in healthy individuals (low GAD65Ab titers, presence of a single autoantibody, lack of a distinct epitope pattern, and presence of anti-Id to diabetes-associated GAD65Ab). In this T2D cohort, GAD65Ab positivity is likely unrelated to the pathogenesis of beta-cell dysfunction. Conclusion: Evidence for islet autoimmunity in the pathophysiology of T2D beta-cell dysfunction is growing, but T1D-associated autoantibodies may not accurately reflect the nature of their autoimmune process.

15.
Clin Immunol ; 149(3): 332-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23803322

RESUMO

Type 1 diabetes (T1D) is a cell-mediated autoimmune disease. New cases of T1D are on the increase and exogenous insulin therapy is the only intervention regularly initiated for T1D patients. Though tremendous strides have been made in prediction of T1D, prevention and intervention strategies have not experienced the same success. In this review, we will discuss some possible reasons why new intervention therapies for T1D have not been implemented into the mainstream treatment regimen for T1D patients. We will also discuss potential caveats for why prevention and intervention trials in T1D may not have experienced the same success as prediction trials.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/prevenção & controle , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Abatacepte , Anticorpos Monoclonais Humanizados/uso terapêutico , Autoimunidade , Complexo CD3/uso terapêutico , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 1/imunologia , Etanercepte , Glutamato Descarboxilase/uso terapêutico , Humanos , Imunoconjugados/uso terapêutico , Imunoglobulina G/uso terapêutico , Insulina/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/patologia , Receptores do Fator de Necrose Tumoral/uso terapêutico
16.
Lancet ; 378(9788): 319-27, 2011 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-21714999

RESUMO

BACKGROUND: Glutamic acid decarboxylase (GAD) is a major target of the autoimmune response that occurs in type 1 diabetes mellitus. In animal models of autoimmunity, treatment with a target antigen can modulate aggressive autoimmunity. We aimed to assess whether immunisation with GAD formulated with aluminum hydroxide (GAD-alum) would preserve insulin production in recent-onset type 1 diabetes. METHODS: Patients aged 3-45 years who had been diagnosed with type 1 diabetes for less than 100 days were enrolled from 15 sites in the USA and Canada, and randomly assigned to receive one of three treatments: three injections of 20 µg GAD-alum, two injections of 20 µg GAD-alum and one of alum, or 3 injections of alum. Injections were given subcutaneously at baseline, 4 weeks later, and 8 weeks after the second injection. The randomisation sequence was computer generated at the TrialNet coordinating centre. Patients and study personnel were masked to treatment assignment. The primary outcome was the baseline-adjusted geometric mean area under the curve (AUC) of serum C-peptide during the first 2 h of a 4-h mixed meal tolerance test at 1 year. Secondary outcomes included changes in glycated haemoglobin A(1c) (HbA(1c)) and insulin dose, and safety. Analysis included all randomised patients with known measurements. This trial is registered with ClinicalTrials.gov, number NCT00529399. FINDINGS: 145 patients were enrolled and treated with GAD-alum (n=48), GAD-alum plus alum (n=49), or alum (n=48). At 1 year, the 2-h AUC of C-peptide, adjusted for age, sex, and baseline C-peptide value, was 0·412 nmol/L (95% CI 0·349-0·478) in the GAD-alum group, 0·382 nmol/L (0·322-0·446) in the GAD-alum plus alum group, and 0·413 nmol/L (0·351-0·477) in the alum group. The ratio of the population mean of the adjusted geometric mean 2-h AUC of C-peptide was 0·998 (95% CI 0·779-1·22; p=0·98) for GAD-alum versus alum, and 0·926 (0·720-1·13; p=0·50) for GAD-alum plus alum versus alum. HbA(1c), insulin use, and the occurrence and severity of adverse events did not differ between groups. INTERPRETATION: Antigen-based immunotherapy therapy with two or three doses of subcutaneous GAD-alum across 4-12 weeks does not alter the course of loss of insulin secretion during 1 year in patients with recently diagnosed type 1 diabetes. Although antigen-based therapy is a highly desirable treatment and is effective in animal models, translation to human autoimmune disease remains a challenge. FUNDING: US National Institutes of Health.


Assuntos
Doenças Autoimunes/terapia , Diabetes Mellitus Tipo 1/terapia , Glutamato Descarboxilase/uso terapêutico , Imunoterapia Ativa , Adolescente , Antígenos/imunologia , Antígenos/uso terapêutico , Doenças Autoimunes/imunologia , Canadá , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/imunologia , Método Duplo-Cego , Feminino , Glutamato Descarboxilase/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
17.
Front Psychol ; 13: 996041, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36570989

RESUMO

We examined posttraumatic growth for 691 participants of the Tragedy Assistance Program for Survivors (TAPS). Peer mentors of bereaved individuals experienced greater posttraumatic growth (PTG) and reported higher psychological health than those who were non-peer mentors. Active involvement in TAPS and resilience consistently and positively predicted all types of PTG. These prediction models were far stronger (R2, AIC) for the suicide-bereaved sample than those bereaved by other causes, and post-hoc analyses suggest suicide-bereaved benefitted more than those bereaved by other causes from active participation in TAPS.

18.
Diabetes Care ; 45(2): 311-318, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34853027

RESUMO

OBJECTIVE: We assessed whether Index60, a composite measure of fasting C-peptide, 60-min C-peptide, and 60-min glucose, could improve the metabolic staging of type 1 diabetes for progression to clinical disease (stage 3) among autoantibody-positive (Ab+) individuals with normal 2-h glucose values (<140 mg/dL). RESEARCH DESIGN AND METHODS: We analyzed 3,058 Type 1 Diabetes TrialNet Pathway to Prevention participants with 2-h glucose <140 mg/dL and Index60 <1.00 values from baseline oral glucose tolerance tests. Characteristics associated with type 1 diabetes (younger age, greater Ab+, higher HLA DR3-DQ2/DR4-DQ8 prevalence, and lower C-peptide) were compared among four mutually exclusive groups: top 2-h glucose quartile only (HI-2HGLU), top Index60 quartile only (HI-IND60), both top quartiles (HI-BOTH), and neither top quartile (LO-BOTH). Additionally, within the 2-h glucose distribution of <140 mg/dL and separately within the Index60 <1.00 distribution, comparisons were made between those above or below the medians. RESULTS: HI-IND60 and HI-BOTH were younger, with greater frequency of more than two Ab+, and lower C-peptide levels, than either HI-2HGLU or LO-BOTH (all P < 0.001). The cumulative incidence for stage 3 was greater for HI-IND60 and HI-BOTH than for either HI-2HGLU or LO-BOTH (all P < 0.001). Those with Index60 values above the median were younger and had higher frequency of two or more Ab+ (P < 0.001) and DR3-DQ2/DR4-DQ8 prevalence (P < 0.001) and lower area under the curve (AUC) C-peptide levels (P < 0.001) than those below. Those above the 2-h glucose median had higher AUC C-peptide levels (P < 0.001), but otherwise did not differ from those below. CONCLUSIONS: Index60 identifies individuals with characteristics of type 1 diabetes at appreciable risk for progression who would otherwise be missed by 2-h glucose staging criteria.


Assuntos
Diabetes Mellitus Tipo 1 , Autoanticorpos , Glicemia/metabolismo , Peptídeo C , Diabetes Mellitus Tipo 1/metabolismo , Glucose , Teste de Tolerância a Glucose , Humanos
19.
Diabetes Care ; 45(12): 2982-2990, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36326757

RESUMO

OBJECTIVE: We studied longitudinal differences between progressors and nonprogressors to type 1 diabetes with similar and substantial baseline risk. RESEARCH DESIGN AND METHODS: Changes in 2-h oral glucose tolerance test indices were used to examine variability in diabetes progression in the Diabetes Prevention Trial-Type 1 (DPT-1) study (n = 246) and Type 1 Diabetes TrialNet Pathway to Prevention study (TNPTP) (n = 503) among autoantibody (Ab)+ children (aged <18.0 years) with similar baseline metabolic impairment (DPT-1 Risk Score [DPTRS] of 6.5-7.5), as well as in TNPTP Ab- children (n = 94). RESULTS: Longitudinal analyses revealed annualized area under the curve (AUC) of C-peptide increases in nonprogressors versus decreases in progressors (P ≤ 0.026 for DPT-1 and TNPTP). Vector indices for AUC glucose and AUC C-peptide changes (on a two-dimensional grid) also differed significantly (P < 0.001). Despite marked baseline metabolic impairment of nonprogressors, changes in AUC C-peptide, AUC glucose, AUC C-peptide-to-AUC glucose ratio (AUC ratio), and Index60 did not differ from Ab- relatives during follow-up. Divergence between nonprogressors and progressors occurred by 6 months from baseline in both cohorts (AUC glucose, P ≤ 0.007; AUC ratio, P ≤ 0.034; Index60, P < 0.001; vector indices of change, P < 0.001). Differences in 6-month change were positively associated with greater diabetes risk (respectively, P < 0.001, P ≤ 0.019, P < 0.001, and P < 0.001) in DPT-1 and TNPTP, except AUC ratio, which was inversely associated with risk (P < 0.001). CONCLUSIONS: Novel findings show that even with similarly abnormal baseline risk, progressors had appreciably more metabolic impairment than nonprogressors within 6 months and that the measures showing impairment were predictive of type 1 diabetes. Longitudinal metabolic patterns did not differ between nonprogressors and Ab- relatives, suggesting persistent ß-cell responsiveness in nonprogressors.


Assuntos
Diabetes Mellitus Tipo 1 , Criança , Humanos , Peptídeo C/metabolismo , Diabetes Mellitus Tipo 1/diagnóstico , Glicemia/metabolismo , Teste de Tolerância a Glucose , Autoanticorpos , Glucose , Progressão da Doença
20.
Diabetes ; 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35061024

RESUMO

Islet autoimmunity may contribute to ß-cell dysfunction in type 2 diabetes (T2D). Its prevalence and clinical significance have not been rigorously determined. In this ancillary study to the Glycemia Reduction Approaches in Diabetes-A Comparative Effectiveness (GRADE) Study, we investigated the prevalence of cellular and humoral islet autoimmunity in patients with T2D duration 4·0±3·0 y, HbA1c 7·5±0·5% on metformin alone. We measured T cell autoreactivity against islet proteins, islet autoantibodies against GAD65, IA2, ZnT8, and ß-cell function. Cellular islet autoimmunity was present in 41·3%, humoral islet autoimmunity in 13·5%, and both in 5·3%. ß-cell function calculated as iAUC-CG and ΔC-peptide(0- 30)/Δglucose(0-30) from an oral glucose tolerance test was lower among T cell-positives (T+) than T cell-negatives (T-) using two different adjustments for insulin sensitivity (iAUC-CG: 13·2% [95% CI 0·3, 24·4%] or 11·4% [95% CI 0·4, 21·2%] lower; ΔC-peptide(0-30)/Δglucose(0-30)) 19% [95% CI 3·1, 32·3%] or 17·7% [95% CI 2·6, 30·5%] lower). T+ patients had 17% higher HbA1c (95% CI 0·07, 0·28) and 7·7 mg/dL higher fasting plasma glucose levels (95% CI 0·2,15·3) than T- patients. We conclude that islet autoimmunity is much more prevalent in T2D patients than previously reported. T cell-mediated autoimmunity is associated with diminished ß-cell function and worse glycemic control.

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