Residual beta-cell function and spontaneous clinical remission in type 1 diabetes mellitus: the role of puberty

Evaluation of type 1 diabetes' partial clinical remission after three years of heterologous adipose tissue derived stromal/stem cells transplantation associated with vitamin D supplementation

BACKGROUND

Mesenchymal stem cell infusion and vitamin D supplementation may have immunomodulatory actions that could prolong the preservation of residual insulin secretion in patients with type 1 diabetes (T1D). Intervention with these agents after onset of T1D could favor the development of a remission phase, with potential clinical impact. We aimed to compare the presence of clinical remission (CR), glycemic control and daily insulin requirement at 6, 12, 18, 24 and 36 months after the diagnosis of T1D using IDAA1c in patients who received therapy with adipose tissue-derived mesenchymal stem cell (ASC) infusion and vitamin D supplementation and a control group.

METHODS

This retrospective cohort study analyzed data from the medical records of patients with T1D diagnosed between 15 and 40 years. Partial CR was defined as an IDAA1c index < 9. Patients in the intervention group received an infusion of adipose tissued-derived mesenchymal stem cells (ASCs) within 3 months after diagnosis and supplementation with 2000 IU of cholecalciferol for 1 year, started on the day following the infusion. Partial CR was also determined using the ISPAD criteria, to assess its agreement with IDAA1c.

RESULTS

A total of 28 patients were evaluated: 7 in the intervention group (group 1) and 21 in the control group (group 2). All patients in group 1 evolved with partial CR while only 46.7% of patients in group 2 had this outcome. Group 1 had a higher frequency of CR when evaluated with IDAA1c and ISPAD criteria. The mean duration of CR varied between the two criteria. Although HbA1c was similar between groups during follow-up, group 1 had a lower total daily insulin requirement (p < 0.005) at all time points. At 36 months, group 1 used 49% of the total daily insulin dose used by group 2 with similar glycemic control.

CONCLUSION

The intervention with infusion of ASC + vitamin D supplementation was associated with partial CR at 6 months. Although there were no differences in CR established by the IDAA1c and ISPAD criteria after three years of follow-up, patients who underwent intervention had nearly the half insulin requirement of controls with conventional treatment, with similar glycemic control.

TRIAL REGISTRATION

37001514.0.0000.5257.

Approaches to Measuring Beta Cell Reserve and Defining Partial Clinical Remission in Paediatric Type 1 Diabetes

CONTEXT

Type 1 diabetes (T1D) results from the autoimmune T-cell mediated destruction of pancreatic beta cells leading to insufficient insulin secretion. At the time of diagnosis of T1D, there is residual beta cell function that declines over the subsequent months to years. Recent interventions have been approved to preserve beta cell function in evolving T1D.

OBJECTIVE

The aim of this review is to summarise the approaches used to assess residual beta cell function in evolving T1D, and to highlight potential future directions.

METHODS

Studies including subjects aged 0 to 18 years were included in this review. The following search terms were used; "(type 1 diabetes) and (partial remission)" and "(type 1 diabetes) and (honeymoon)". References of included studies were reviewed to determine if additional relevant studies were eligible.

RESULTS

There are numerous approaches to quantifying beta cell reserve in evolving T1D. These include c-peptide measurement after a mixed meal or glucagon stimuli, fasting c-peptide, the urinary c-peptide/creatinine ratio, insulin dose-adjusted haemoglobin A1c, and other clinical models to estimate beta cell function. Other biomarkers may have a role, including the proinsulin/c-peptide ratio, cytokines, and microRNA. Studies using thresholds to determine if residual beta cell function is present often differ in values used to define remission.

CONCLUSIONS

As interventions are approved to preserve beta cell function, it will become increasingly necessary to quantify residual beta cell function in research and clinical contexts. In this report, we have highlighted the strengths and limitations of the current approaches.

Honeymoon phase in type 1 diabetes mellitus: A window of opportunity for diabetes reversal?

The knowledge of the pathogenesis of type 1 diabetes mellitus (T1DM) continues to rapidly evolve. The natural course of the disease can be described in four clinical stages based on the autoimmune markers and glycemic status. Not all individuals of T1DM progress in that specific sequence. We hereby present a case of T1DM with a classical third phase (honeymoon phase) and discuss the intricacies of this interesting phase along with a possible future promise of "cure" with the use of immunotherapies. We now know that the course of T1DM may not be in only one direction towards further progression; rather the disease may have a waxing and waning course with even reversal of type 1 diabetes concept being discussed. The third phase popularly called the "honeymoon phase", is of special interest as this phase is complex in its pathogenesis. The honeymoon phase of T1DM seems to provide the best window of opportunity for using targeted therapies using various immunomodulatory agents leading to the possibility of achieving the elusive "diabetes reversal" in T1DM. Identifying this phase is therefore the key, with a lot of varying criteria having been proposed.

The role of specific pancreatic antibodies in the differential diagnosis of complete clinical and laboratory remission of type 1 diabetes mellitus and MODY in children

BACKGROUND: T1D is characterized by autoimmune destruction of pancreatic β-cells, which develops due to genetic and environmental risk factors. Shortly after initiating the treatment with insulin, 80% of children with T1D may require smaller doses of insulin and develop clinical and laboratory remission of the disease so called «honeymoon». The issue of whether there is a need of differential diagnosis between autoimmune DM and non-immune forms of DM raises in cases of preclinical diagnosis of T1D and laboratory remission for more than 6 months.

AIM: To study the clinical, immunological, genetic characteristics of T1D remission phase and MODY in children, to determine the diagnostic criteria for T1D and MODY in children.

MATERIALS AND METHODS: A single-centre, cross sectional noncontrolled comparative study of two independent cohorts. Data of 150 children examined in the Endocrinology Research Center (January 2016–June 2021). First cohort included patients with complete clinical and laboratory remission of T1D (n=36), second cohort included patients with MODY, confirmed by genetic study (n=114).

RESULTS: The median age of diabetes manifestation was significantly higher in patients with T1D — 11.25 years [8.33; 13.78] than in patients with MODY — 7.5 years [4.6; 12.2] (p=0.004). In patients with T1D remission the level of glycated hemoglobin was 6.0% [5.6; 6.4], in group with MODY — 6.5% [6.2; 6.7] (p<0.001). Patients with monogenic diabetes had impaired fasting glucose — 6.27 mmol/l [5.38; 6.72], while patients with remission phase had normoglycemia — 5.12 mmol/l [4.17; 5.87]. The oral glucose tolerance test was perform to all patients, two-hour glucose level did not significantly differ in two groups (p=0.08). A strong family history of diabetes in patients with MODY registered more often (93% vs. 66.7%). A positive autoantibody titer detected more often in patients with remission of T1D (77.8%) than in patients with MODY (11.4%). In addition, no more than 1 type of autoantibodies was detected in patients with MODY.

CONCLUSION: Antibodies ZnT8 and IA2 showed the greatest significance for the differential diagnosis of T1D and MODY in cases with long absents of insulin requirement in children with diabetes mellitus. Genetic test is recommended in seronegative cases. If only one type of AT is detected, specialist should decide on the need to do diagnostic genetic test based on a comprehensive analysis of the patient’s clinic characteristics, including family history, manifestation and blood glucose levels.

Partial remission in children and adolescents with type 1 diabetes: an analysis based on the insulin dose-adjusted hemoglobin A1c

OBJECTIVES

Most patients with type 1 diabetes (T1D) experience a transient phase of partial remission (PR). This study aimed to identify the demographic and clinical factors associated with PR.

METHODS

This was a longitudinal retrospective cohort study of 133 children and adolescents with T1D. PR was defined by the gold standard insulin dose-adjusted hemoglobin A1c (HbA1c) (IDAA1c) of ≤9.

RESULTS

Remission was observed in 77 (57.9%) patients. At diagnosis, remitters had significantly higher pH (7.3 ± 0.12 vs. 7.23 ± 0.15, p=0.003), higher C-peptide levels (0.45 ± 0.31 ng/mL vs. 0.3 ± 0.22, p=0.003), and they were significantly older (9.3 ± 3.6 years vs. 7.3 ± 4.2, p=0.008) compared with non-remitters. PR developed more frequently in patients without diabetic ketoacidosis (DKA) (p=0.026) and with disease onset after age 5 (p=0.001). Patients using multiple daily insulin regimen were more likely to experience PR than those treated with a twice daily regimen (63.9 vs. 32%, p=0.004). Only age at onset was an independent predictor of PR (OR: 1.12, 95% CI: 1-1.25; p=0.044). Remitters had lower HbA1c levels and daily insulin requirement from diagnosis until one year after diagnosis (p<0.001). PR recurred in 7 (9%) patients. The daily insulin requirement at three months was lower in remitters with PR recurrence compared to those without (0.23 ± 0.14 vs. 0.4 ± 0.17 U/kg/day, p=0.014).

CONCLUSIONS

Addressing factors associated with the occurrence of PR could provide a better comprehension of metabolic control in T1D. The lack of DKA and higher C-peptide levels may influence PR, but the main factor associated with PR presence was older age at onset. PR may recur in a small proportion of patients.

Residual β-Cell Function in Type 1 Diabetes Followed for 2 Years after 3C Study

OBJECTIVE

To investigate the natural history and related factors of the pancreatic β-cell function in Chinese type 1 diabetic patients from 3C study Shantou center.

METHOD

Stimulated C-peptide levels from follow-up data of 201 individuals in 3C study Shantou subgroup starting in 2012 were used. Residual β-cell function was defined as stimulated C - peptide level ≥ 0.2 pmol/mL, on the basis of cut-points derived from the Diabetes Control and Complications Trial (DCCT).

RESULTS

36.8% of patients had residual β-cell function, and the percentage was 68.2% in newly diagnosed diabetic patients. COX regression analysis indicated that the age of diagnosis, HbA1C level, and duration were independent factors of residual β-cell function in individuals with ≤5 years duration, but in those with duration ≥5 years, only the age of diagnosis was a predictor. The pancreatic β-cell function mainly declined in the first 5 years of the duration, and the rate of decline was correlated negatively with the duration and age of diagnosis. Receiver operating characteristic (ROC) analysis indicated that the cut-off point of stimulated C-peptide was 0.615 pmol/mL in patients with <5 years duration to have 7% HbA1c.

CONCLUSION

Age at diagnosis was the strongest predictor for residual C-peptide. There was a more rapid decline of stimulated C-peptide in duration ≤5 years and younger patients. Therefore, intervention therapies of β-cells should start from the early stage, and the recommended target goal of stimulated C-peptide is 0.615 pmol/mL or above.

Clinical Remission of Type 1 Diabetes Predicts Higher Insulin Sensitivity at 7 Years from Diagnosis of the Disease

Background: Clinical remission of type 1 diabetes is not only associated with regeneration of beta cells and preserved insulin secretion but also with increased insulin sensitivity. The aim of the study was to determine the association between presence of remission in the first year of type 1 diabetes and insulin resistance at 7 years from diagnosis of the disease. Material and Methods: A total of 108 consecutive patients with newly diagnosed type 1 diabetes were followed prospectively. During the follow-up time, the onset and duration of clinical remission were registered. Seventy-four patients were included in the final analysis. Insulin sensitivity was assessed by the glucose disposal rate (GDR), determined using the hyperinsulinemic-euglycemic clamp, performed at 7 years from diagnosis of diabetes. Patients were divided into groups with GDR <4.5 mg/(kg·min) (G1-lower insulin sensitivity group) and GDR ≥4.5 mg/(kg·min) (G2-higher insulin sensitivity group). Results: Higher insulin sensitivity was observed in the remission group [GDR 6.2 interquartile range (IQR) 4.2-7.0 mg/(kg·min) vs. 3.8 (IQR 3.0-4.8) mg/(kg·min); P = 0.01]. Furthermore, in G2 group, the duration of remission was longer than in G1 group: (351 [IQR 206-561] days vs. 70 [IQR 0-289] days; P = 0.002). Also, the GDR value correlated positively with duration of remission (r = 0.42; P = 0.002). In the multivariate logistic regression model, including age, sex, body mass index at diagnosis, and presence of remission, the remission period was independently associated with a higher GDR value (odds ratio 10.88; 95% confidence interval: 1.70-69.50; P = 0.009]. Conclusions: Patients with type 1 diabetes who entered remission at the beginning of the disease, despite its ending, have higher insulin sensitivity at 7 years after diagnosis of diabetes than nonremitters.

Influence of Age on Partial Clinical Remission among Children with Newly Diagnosed Type 1 Diabetes

Partial clinical remission (PCR) is a transitory period characterized by the residual endogenous insulin secretion following type 1 diabetes (T1D) diagnosis and introducing the insulin therapy. Scientific interest in PCR has been recently increasing, as this phase could be crucial to preserve functional beta cells after T1D onset, also taking advantage of new therapeutic opportunities. The aim of this study was to assess the frequency, duration and associated factors of PCR in children newly diagnosed with T1D. Our cohort study included 167 pediatric patients aged 13.8 ± 4.1 years. The association of clinical and laboratory factors with the occurrence and duration of PCR was evaluated via logistic regression and multivariable generalized linear model, respectively. PCR occurred in 63.5% of the examined patients. Patients who achieved the remission phase were significantly older, and they had lower daily insulin requirement compared with non-remitters. PCR was positively associated to body mass index (OR = 1.11; p = 0.032), pH value (OR 49.02; p = 0.003) and c-peptide levels (OR 12.8; p = 0.002). The average duration of PCR was 13.4 months, and older age at diagnosis was the only predictor factor. Two years after diagnosis remitter patients had lower HbA1c and daily insulin requirement.

Combination therapy with anti-CD20 mAb and IL-10 gene to reverse type 1 diabetes by attenuating pancreatitis and inhibiting apoptosis in NOD mice

AIMS

To assess the combination therapy of anti-CD20 mabs and adenovirus-mediated interleukin-10 (IL-10) gene delivery on the prevention of type 1 diabetes (T1D) in non-obese diabetes (NOD) mice.

MAIN METHODS

In present study, we simultaneously blocked the B cell interactions and recovered the Th cell subset proportion by using through anti-CD20 Mab and adenovirus-mediated gene delivery of IL-10, respectively. After 9 consecutive days of combination therapy, various measurements, including hematoxylin-eosin staining (HE), terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling assay (TUNEL), immunohistochemistry, ELISA, PCR and western blot were applied to further assess the efficacy.

KEY FINDINGS

The results suggested that the combination intervention reduced the T1D-associated morbidity of NOD mice, promote insulin secretion, control blood glucose and ease pancreatitis. Moreover, the combination therapy might play a protective role in pancreatic β cells by suppressing the expression of TNF-α and Fas, blocking the Caspase-8 and Caspase-3 apoptotic pathways and activating the Bcl-2 anti-apoptotic pathway. Finally, the combination intervention may up-regulate the gene expression of CK-19 and PDX-1 and further accelerate the differentiation and proliferation of pancreatic β cells.

SIGNIFICANCE

Therefore, the combination intervention with anti-CD20 mabs and the IL-10 gene plays a role in the prevention of T1D to some extent in NOD mice.

Gluten-free diet in children with recent-onset type 1 diabetes: A 12-month intervention trial

AIM

To test whether a gluten-free diet (GFD) is associated with the deceleration of the decline in beta-cell capacity in non-coeliac children with recently diagnosed type 1 diabetes.

METHODS

Forty-five children (aged 10.2 ± 3.3 years) were recruited into a self-selected intervention trial: 26 started with a GFD within a median of 38 days postonset, whereas 19 remained on a standard diet. The main outcomes were the decline in C-peptide area under the curve (AUC) in mixed-meal tolerance tests (MMTTs) at 6 and 12 months relative to 1 month after diabetes onset and the difference in insulin dose, insulin dose-adjusted A1c (IDAA1c) and HbA1c assessed every 3 months. The adherence to the GFD was verified by immunoreactive gluten in the stool and by food questionnaires at every visit. Quality of life (QoL) questionnaires were administered to the participants at the end of the intervention at 12 months. The data were analysed as per protocol (in 39 subjects who duly completed the whole follow-up: 20 in the GFD group, 19 in the control group) by linear and longitudinal regression models adjusted for sex, age and baseline variables.

RESULTS

At 12 months, the difference in C-peptide AUC between subjects in the GFD group and controls was 205 pmol/L (95% CI -223 to 633; P = 0.34) in a model adjusted for age, sex and body weight, and for baseline insulin dose, MMTT C-peptide AUC and HbA1c assessed at 1 month after diagnosis. In a longitudinal analysis of all three time points adjusted for age, sex and body weight, C-peptide declined more slowly in the GFD group than in controls, with the difference in trends being 409 pmol/L/year (P = 0.04). The GFD group had a marginally lower insulin dose (by 0.15 U/kg/day; P = 0.07), a lower IDAA1c (by 1.37; P = 0.01) and a lower mean HbA1c (by 0.7% [7.8 mmol/mol]; P = 0.02) than those of the controls at 12 months. There was no appreciable difference between the groups in daily carbohydrate intake (P = 0.49) or in the QoL reported by the patients (P = 0.70) and their parents/caregivers (P = 0.59).

CONCLUSIONS

A GFD maintained over the first year after type 1 diabetes diagnosis was associated with better HbA1c and a prolonged partial remission period. There was a hint of slower C-peptide decline but the association was not strong enough to make definite conclusions.

The remission phase in type 1 diabetes: Changing epidemiology, definitions, and emerging immuno-metabolic mechanisms

Type 1 diabetes mellitus (T1DM) is characterized by irreversible islet β cell destruction. During the progression of this disease, some patients with T1DM experience a phase of remission known as honeymoon or partial remission (PR) that is mainly characterized by satisfactory glycemic control and the transient recovery of islet β cell function. This special phase is a good model for studying the mechanism of β cell protection, might serve as a proper intervention period for immunotherapy, and may be related to disease prognosis. This special stage is highly valuable for studies aiming to identify possible targets that may be used to cure T1DM. An in-depth understanding of the diagnosis, epidemiology, and possible mechanisms of the PR phase is highly needed. In general, patients enter the PR phase approximately 3 months after starting insulin therapy, and this phase could be sustained for 6 to 9 months. Current research increasingly focuses on the metabolic and immunological aspects to constantly update our understanding of this phase. This review concentrates on the PR phase of T1DM to provide a comprehensive outlook of its epidemiology, diagnostic criteria, and underlying immune metabolic mechanisms.

Atypical hyperglycemia presentation suggests considering a diagnostic of other types of diabetes: first reported GCK-MODY in Perú

Background

Prevalence of maturity-onset diabetes of the young (MODY) is estimated between 1 and 2% of all diabetes cases. In Latin-America little information has been described about the frequency of the disease, perhaps due to limited access to genetic studies.

Case presentation

We present the case of a male patient with a history of two years of fatigue, mild hyperglycemia and intermittent polyuria, accompanied by a recent history of weight loss. He was diagnosed initially as type 2 diabetes, but in the follow-up as a patient with type 1 diabetes. He required relatively low doses of insulin and was evaluated in the endocrinology service at a hospital in Lima. The results of glucose, insulin and C-peptide in the oral glucose tolerance test (OGTT) performed were not consistent with a type 1 diabetes. Moreover, the age of the patient and the clinical characteristics did not strongly suggest a diagnosis of type 2 diabetes either. These clinical features had prompted us to carry out the genetic study. The genetic test performed with a genetic MODY panel through a massive sequencing. Heterozygous pathogenic for a variant in GCK gene was found c.629C>T p.(Thr210Met). His parents were negative for this variant after performed the genetic test.

Conclusions

This is the first case of MODY for a pathogenic variant in the GCK gene reported in Perú. The genetic evaluation of a clinical suspicion of MODY is important to confirm the diagnosis and establish an adequate treatment in patients.

The adenosine, adrenergic and opioid pathways in the regulation of insulin secretion, beta cell proliferation and regeneration

Insulin, a key hormone produced by pancreatic beta cells precisely regulates glucose metabolism in vertebrates. In type 1 diabetes, the beta cell mass is destroyed, a process triggered by a combination of environmental and genetic factors. This ultimately results in absolute insulin deficiency and dysregulated glucose metabolism resulting in a number of detrimental pathophysiological effects. The traditional focus of treating type 1 diabetes has been to control blood sugar levels through the administration of exogenous insulin. Newer approaches aim to replace the beta cell mass through pancreatic or islet transplantation. Type 2 diabetes results from a relative insulin deficiency for the prevailing insulin resistance. Treatments are generally aimed at reducing insulin resistance and/or augmenting insulin secretion and the use of insulin itself is often required. It is increasingly being recognized that the beta cell mass is dynamic and increases insulin secretion in response to beta cell mitogens and stress signals to maintain glycemia within a very narrow physiological range. This review critically discusses the role of adrenergic, adenosine and opioid pathways and their interrelationship in insulin secretion, beta cell proliferation and regeneration.

Factors Influencing Frequency and Duration of Remission in Children and Adolescents Newly Diagnosed with Type 1 Diabetes

Background

This study aimed to determine the frequency and duration of remission in children and adolescents newly diagnosed with type 1 diabetes and to investigate factors associated with these parameters.

Material/Method

Fifty patients newly diagnosed with T1DM were followed for 1 year. Daily insulin requirement of less than 0.5 U/kg/day dose when the HbA1c value is less than 8% was regarded as partial remission. Patients were grouped according to their remission duration. Clinical and laboratory characteristics of the remission groups and non-remission groups were compared to find factors influencing remission and to investigate their contribution to the duration of remission.

Results

Remission was observed in 24 (48%) out of 50 patients included in the study. Remission frequency was found to be associated with age, sex, and puberty. Longer duration of remission was more frequent in the younger age group, in pre-pubertal stage, and in male patients. Daily insulin dose and basal insulin requirement of those who went into remission was found to be significantly lower than in the other patients at discharge.

Conclusions

Decreased daily total and basal insulin requirement at discharge are valuable in predicting remission. The remission process in type 1 diabetes still has many characteristics that need to be clarified. Therefore, more extensive studies are needed.

Markers influencing the presence of partial clinical remission in patients with newly diagnosed type 1 diabetes

BACKGROUND

The aim of the study was to compare the selected markers in children with and without partial clinical remission (CR) of newly diagnosed type 1 diabetes (T1D).

METHODS

The study group consisted of 186 patients (F/M; 87/99) at onset of T1D and 24 months of follow-up. Partial CR was defined as insulin requirement <0.5 IU/kg and glycated hemoglobin (HbA1c) <7%.

RESULTS

Partial CR was observed in 115/186 (61.83%) of patients. At diagnosis body mass index standard deviation (BMI SDS) was higher among remitters than in non-remitters (p=0.0051) and remitters were younger (p=0.0029). In the follow-up a higher triglyceride concentration in non-remitters compared to remitters (p=0.0455) and a lower high density lipoprotein (HDL) cholesterol level (p=0.0119) were noticed.

CONCLUSIONS

Younger age and higher BMI at diagnosis of T1D can predispose to partial CR in children. In patients with CR of T1D after 2 years of follow-up a lipid profile improvement is observed.

Partial clinical remission in type 1 diabetes: a comparison of the accuracy of total daily dose of insulin of <0.3 units/kg/day to the gold standard insulin-dose adjusted hemoglobin A1c of ≤9 for the detection of partial clinical remission

BACKGROUND

It is unclear whether the gold standard test for the detection of partial clinical remission (PCR) in new-onset type 1 diabetes (T1D), the insulin-dose adjusted Hemoglobin A1c (IDAA1c) of ≤9, is superior to a new tool, total daily dose of insulin (TDD) of <0.3 units/kg/day. The aim of the study was to test the superiority of IDAA1c over TDD of <0.3 units/kg/day for the detection of PCR.

METHODS

A retrospective analysis of 204 subjects of ages 2-14 years, mean age 7.9±3.2 years, (male 7.8±3.4 years, [n=98]; female 7.9±3.0 years, [n=106], p=0.816) with new-onset T1D. Anthropometric and biochemical data were collected for the first 36 months of disease. PCR was defined by both IDAA1c≤9 and TDD<0.3 units/kg/day.

RESULTS

There were 86 (42.2%) (age 9.1±3.0 years; male 57%) remitters by IDAA1c≤9 criterion, and 82 (40.2%) remitters (age 7.3±2.8 years) by TDD of <0.3 units/kg/day criterion (p=0.655). The duration of PCR was 10.0±6.1 months using TDD<0.3 units/kg/day, and 9.2±5.5 months using IDAA1c (p=0.379). Subjects in PCR as denoted by TDD<0.3 units/kg/day had 1.44 times increased probability of entering PCR than those denoted by IDAA1c of ≤9, after adjusting for BMI, bicarbonate, and HbA1c:(OR=1.44, 95% CI [1.03-2.00], p=0.033). Peak prevalence for PCR was at 6-12 months by either definition; more subjects were in PCR at 6 months by IDAA1c ≤9: 62/86 (72.1%) than by TDD<0.3 units/kg/day: 43/82 (52.4%), (p=0.011).

CONCLUSIONS

There were no significant differences in the number of remitters, duration of PCR, or the time of peak remission defined by IDAA1c of ≤9 or TDD of <0.3 units/kg/day.

Influence of remission and its duration on development of early microvascular complications in young adults with type 1 diabetes

INTRODUCTION

Prevalence of partial remission ranges between 20% and 80% in the initial course of type 1 diabetes. In this phase of the disease, a substantial insulin secretion contributes to good metabolic control. The aim of the study was to determine the association between presence of partial remission and occurrence of microangiopathy complications in type 1 diabetes.

MATERIAL AND METHODS

Ninety-eight consecutive patients with newly diagnosed type 1 diabetes were asked to participate in a cohort study. Partial remission was defined as the time in which all of the following criteria were met: HbA1c below 6.5% (48mmol/mol), daily insulin requirement below 0.3 U/kg body weight and serum Cpeptide concentration above 0.5ng/ml. Patients were divided into those who were in remission at any time during follow-up (remitters) and non-remitters. After 7years of follow-up, the occurrence of microangiopathy complications was analyzed. In statistical analysis, Mann-Whitney test, chi(2) test and Fisher test were used for analysis between groups. We applied a Cox's multivariate regression model and univariate regression method. P<0.05 was considered statistically significant.

RESULTS

In univariate logistic regression, a significant association was found between absence of remission and occurrence of at least one microvascular complication. In the Cox proportional hazards regression model that included clinically significant parameters at diagnosis (presence of ketoacidosis, cigarette smoking and HbA1c value) as covariates, absence of remission was associated with occurrence of chronic complications of diabetes at 7years [HR: 3.65 (95% CI 1.23-4.56), p=0.04]. In non-remitters, higher incidence of at least one microvascular complication (46.4% vs. 7.6%), higher incidence of retinopathy (42.8% vs. 5.7%), and neuropathy (21.4% vs. 1.9%) was found.

CONCLUSIONS

Occurrence of partial remission of diabetes is associated with a reduced risk of chronic microvascular complications at 7-year follow-up.

Spontaneous complete remission of type 1 diabetes mellitus in an adult - review and case report

Type 1 diabetes mellitus (T1DM) is an autoimmune condition that results in low plasma insulin levels by destruction of beta cells of the pancreas. As part of the natural progression of this disease, some patients regain beta cell activity transiently. This period is often referred to as the ‘honeymoon period’ or remission of T1DM. During this period, patients manifest improved glycemic control with reduced or no use of insulin or anti-diabetic medications. The incidence rates of remission and duration of remission is extremely variable. Various factors seem to influence the remission rates and duration. These include but are not limited to C-peptide level, serum bicarbonate level at the time of diagnosis, duration of T1DM symptoms, haemoglobin A1C (HbA1C) levels at the time of diagnosis, sex, and age of the patient. Mechanism of remission is not clearly understood. Extensive research is ongoing in regard to the possible prevention and reversal of T1DM. However, most of the studies that showed positive results were small and uncontrolled. We present a 32-year-old newly diagnosed T1DM patient who presented with diabetic ketoacidosis (DKA) and HbA1C of 12.7%. She was on basal bolus insulin regimen for the first 4 months after diagnosis. Later, she stopped taking insulin and other anti-diabetic medications due to compliance and logistical issues. Eleven months after diagnosis, her HbA1C spontaneously improved to 5.6%. Currently (14 months after T1DM diagnosis), she is still in complete remission, not requiring insulin therapy.

Disease progression among 446 children with newly diagnosed type 1 diabetes located in Scandinavia, Europe, and North America during the last 27 yr

OBJECTIVE

To clarify whether the rate of decline in stimulated C-peptide (SCP) from 2 to 15 months after diagnosis has changed over an interval of 27 yr.

RESEARCH DESIGN AND METHODS

The rate of decline in SCP levels at 1, 2, 3, 6, 9, 12, and 15 months after diagnosis was compared in four paediatric cohorts from Scandinavian and European countries including 446 children with new onset type 1 diabetes (T1D, 1982-2004). Findings were evaluated against 78 children (2004-2009) from the TrialNet studies.

RESULTS

The mean rate of decline [%/month (±SEM)] in SCP for a 10-yr-old child was 7.7%/month (±1.5) in the 1982-1985 Cohort, 6.3%/month (±1.7) in the 1995-1998 Cohort, 7.8%/month (±0.7) in the 1999-2000 Cohort, and 10.7%/month (±0.9) in the latest 2004-2005 Cohort (p = 0.05). Including the TrialNet Cohort with a rate of decline in SCP of 10.0%/month (±0.9) the differences between the cohorts are still significant (p = 0.039). The rate of decline in SCP was negatively associated with age (p < 0.0001), insulin antibodies (IA) (p = 0.003), and glutamic acid decarboxylase-65 (GAD65A) (p = 0.03) initially with no statistically significant effect of body mass index (BMI) Z-score at 3 months. Also, at 3 months the time around partial remission, the effect of age on SCP was significantly greater in children ≤5 yr compared with older children (p ≤ 0.0001).

CONCLUSIONS

During the past 27 yr, initial C-peptide as well as the rate of C-peptide decline seem to have increased. The rate of decline was affected significantly by age, GAD65A, and IA, but not BMI Z-score or initial C-peptide.

Residual β-Cell function 3-6 years after onset of type 1 diabetes reduces risk of severe hypoglycemia in children and adolescents

OBJECTIVE

To determine the prevalence of residual β-cell function (RBF) in children after 3-6 years of type 1 diabetes, and to examine the association between RBF and incidence of severe hypoglycemia, glycemic control, and insulin requirements.

RESEARCH DESIGN AND METHODS

A total of 342 children (173 boys) 4.8-18.9 years of age with type 1 diabetes for 3-6 years were included. RBF was assessed by testing meal-stimulated C-peptide concentrations. Information regarding severe hypoglycemia within the past year, current HbA1c, and daily insulin requirements was retrieved from the medical records and through patient interviews.

RESULTS

Ninety-two children (27%) had RBF >0.04 nmol/L. Patients with RBF <0.04 nmol/L were significantly more likely to have severe hypoglycemia than patients with RBF >0.04 nmol/L (odds ratio, 2.59; 95% CI, 1.10-7.08; P < 0.03). HbA1c was significantly higher in patients with RBF <0.04 nmol/L compared with patients with RBF >0.04 nmol/L (mean, 8.49 ± 0.08% [69.3 ± 0.9 mmol/mol] vs. 7.92 ± 0.13% [63.1 ± 1.4 mmol/mol]; P < 0.01), and insulin requirements were significantly lower in patients with RBF >0.2 nmol/L (mean ± SE: 1.07 ± 0.02 vs. 0.93 ± 0.07 units/kg/day; P < 0.04).

CONCLUSIONS

We demonstrated considerable phenotypic diversity in RBF among children after 3-6 years of type 1 diabetes. Children with RBF are at lower risk for severe hypoglycemia, have better diabetes regulation, and have lower insulin requirements compared with children without RBF. There appears to be a lower limit for stimulated RBF of ∼0.04 nmol/L that confers a beneficial effect on hypoglycemia and metabolic control.

Transcriptional signatures as a disease-specific and predictive inflammatory biomarker for type 1 diabetes

The complex milieu of inflammatory mediators associated with many diseases is often too dilute to directly measure in the periphery, necessitating development of more sensitive measurements suitable for mechanistic studies, earlier diagnosis, guiding therapeutic decisions and monitoring interventions. We previously demonstrated that plasma samples from recent-onset type 1 diabetes (RO T1D) patients induce a proinflammatory transcriptional signature in freshly drawn peripheral blood mononuclear cells (PBMCs) relative to that of unrelated healthy controls (HC). Here, using cryopreserved PBMC, we analyzed larger RO T1D and HC cohorts, examined T1D progression in pre-onset samples, and compared the RO T1D signature to those associated with three disorders characterized by airway infection and inflammation. The RO T1D signature, consisting of interleukin-1 cytokine family members, chemokines involved in immunocyte chemotaxis, immune receptors and signaling molecules, was detected during early pre-diabetes and found to resolve post-onset. The signatures associated with cystic fibrosis patients chronically infected with Pseudomonas aeruginosa, patients with confirmed bacterial pneumonia, and subjects with H1N1 influenza all reflected immunological activation, yet each were distinct from one another and negatively correlated with that of T1D. This study highlights the remarkable capacity of cells to serve as biosensors capable of sensitively and comprehensively differentiating immunological states.

Association of adiponectin, interleukin (IL)-1ra, inducible protein 10, IL-6 and number of islet autoantibodies with progression patterns of type 1 diabetes the first year after diagnosis

The progression of type 1 diabetes after diagnosis is poorly understood. Our aim was to assess the relation of disease progression of juvenile-onset type 1 diabetes, determined by preserved beta cell function the first year after diagnosis, with systemic cytokine concentrations and number of autoantibodies. Juvenile patients (n = 227) had a meal-stimulated C-peptide test 1 and 6 months after diagnosis. On the basis of the C-peptide course for the duration of 1-6 months, four progression groups were defined: patients with persistently low beta cell function ('stable-low'), rapid progressers, slow progressers and remitters. Serum concentrations of adiponectin, interleukin (IL)-1ra, inducible protein 10 (IP-10), IL-6 and glutamic acid decarboxylase (GAD), IA-2A and islet-cell antibodies (ICA) were measured at 1, 6 and 12 months. We found that adiponectin concentrations at 1 month predicted disease progression at 6 months (P = 0·04). Patients with low adiponectin had a higher probability of becoming remitters than rapid progressers, odds ratio 3·1 (1·3-7·6). At 6 and 12 months, adiponectin differed significantly between the groups, with highest concentrations among stable-low and rapid progressers patients (P = 0·03 and P = 0·006). IL-1ra, IP-10 and IL-6 did not differ between the groups at any time-point. The number of autoantibodies differed significantly between the groups at 1 month (P = 0·04), where rapid progressers had the largest number. There was no difference between the groups in human leucocyte antigen-associated risk. We define progression patterns distinguishing patients diagnosed with low beta cell function from those with rapid decline, slow decline or actual increase in beta cell function, pointing to different mechanisms of disease progression. We find that adiponectin concentration at 1 month predicts, and at 6 and 12 months associates with, distinct progression patterns.

Multinational study in children and adolescents with newly diagnosed type 1 diabetes: association of age, ketoacidosis, HLA status, and autoantibodies on residual beta-cell function and glycemic control 12 months after diagnosis

OBJECTIVE

To identify predictors of residual beta-cell function and glycemic control during the first 12 months after the diagnosis of type 1 diabetes (T1D).

SUBJECTS AND METHODS

Clinical information and blood samples were collected from 275 children. HbA1c, antibodies, HLA typing and mixed meal-stimulated C-peptide levels 1, 6, and 12 months after diagnosis were analyzed centrally.

RESULTS

Mean age at diagnosis was 9.1 yr. DKA with standard bicarbonate <15 mmol/L was associated with significantly poorer residual beta-cell function 1 (p = 0.004) and 12 months (p = 0.0003) after diagnosis. At 12 months, the decline in stimulated C-peptide levels compared with the levels at 1 month was 69% in the youngest age group and 50% in patients 10 yr and above (p < 0.001). Stimulated C-peptide at 12 months was predicted by younger age (p < 0.02) and bicarbonate levels at diagnosis (p = 0.005), and by stimulated C-peptide (p < 0.0001), postmeal blood glucose (p = 0.0004), insulin antibodies (IA; p = 0.02) and glutamic acid decarboxylase antibodies (GADA; p = 0.0004) at 1 month. HbA1c at 12 months was predicted by HbA1c at diagnosis (p < 0.0001), GADA at 1 month (p = 0.01), and non-white Caucasian ethnicity (p = 0.002).

CONCLUSIONS

Younger age, ketoacidosis at diagnosis, and IA and GADA 1 month after diagnosis were the strongest explanatory factors for residual beta-cell function at 12 months. Glycemic control at 12 months was influenced predominantly by ethnicity, HbA1c at diagnosis, and GADA at 1 month.

Apoptosis of CD4+ CD25(high) T cells in type 1 diabetes may be partially mediated by IL-2 deprivation

Background

Type 1 diabetes (T1D) is a T-cell mediated autoimmune disease targeting the insulin-producing pancreatic β cells. Naturally occurring FOXP3⁺CD4⁺CD25^high regulatory T cells (T_regs) play an important role in dominant tolerance, suppressing autoreactive CD4⁺ effector T cell activity. Previously, in both recent-onset T1D patients and β cell antibody-positive at-risk individuals, we observed increased apoptosis and decreased function of polyclonal T_regs in the periphery. Our objective here was to elucidate the genes and signaling pathways triggering apoptosis in T_regs from T1D subjects.

Principal Findings

Gene expression profiles of unstimulated T_regs from recent-onset T1D (n = 12) and healthy control subjects (n = 15) were generated. Statistical analysis was performed using a Bayesian approach that is highly efficient in determining differentially expressed genes with low number of replicate samples in each of the two phenotypic groups. Microarray analysis showed that several cytokine/chemokine receptor genes, HLA genes, GIMAP family genes and cell adhesion genes were downregulated in T_regs from T1D subjects, relative to control subjects. Several downstream target genes of the AKT and p53 pathways were also upregulated in T1D subjects, relative to controls. Further, expression signatures and increased apoptosis in T_regs from T1D subjects partially mirrored the response of healthy T_regs under conditions of IL-2 deprivation. CD4⁺ effector T-cells from T1D subjects showed a marked reduction in IL-2 secretion. This could indicate that prior to and during the onset of disease, T_regs in T1D may be caught up in a relatively deficient cytokine milieu.

Conclusions

In summary, expression signatures in T_regs from T1D subjects reflect a cellular response that leads to increased sensitivity to apoptosis, partially due to cytokine deprivation. Further characterization of these signaling cascades should enable the detection of genes that can be targeted for restoring T_reg function in subjects predisposed to T1D.

The honeymoon phase: intersection of metabolism and immunology

PURPOSE OF REVIEW

Even though the honeymoon phase in type 1 diabetes mellitus has been well known, its underlying pathogenic mechanisms remain poorly described. The common explanation that it occurs due to 'beta-cell rest' on initiation of insulin therapy seems inadequate based on recent observations and studies and its underlying immunological aspects overlooked.

RECENT FINDINGS

In this article, we will review the metabolic and immunological aspects of the honeymoon phase and we will present our current model of the pathophysiology of this phase. Our view is that it is one of many phases of remission occurring basically due to development of adaptive immune tolerance along the course of type 1 diabetes. We will also review new findings of the interplay between metabolic factors (ambient glucose level) and immune function.

SUMMARY

The honeymoon phase provides a unique model to understand the pathogenesis of type 1 diabetes. Research to unravel its immune pathogenesis is needed. It may turn out that the optimum form of intervention in type 1 diabetes is one that combines enhancement of antigen-specific adaptive immune tolerance with optimized metabolic control in order to keep cytotoxic T cells anergic.

New definition for the partial remission period in children and adolescents with type 1 diabetes

OBJECTIVE To find a simple definition of partial remission in type 1 diabetes that reflects both residual beta-cell function and efficacy of insulin treatment. RESEARCH DESIGN AND METHODS A total of 275 patients aged <16 years were followed from onset of type 1 diabetes. After 1, 6, and 12 months, stimulated C-peptide during a challenge was used as a measure of residual beta-cell function. RESULTS By multiple regression analysis, a negative association between stimulated C-peptide and A1C (regression coefficient -0.21, P < 0.001) and insulin dose (-0.94, P < 0.001) was shown. These results suggested the definition of an insulin dose-adjusted A1C (IDAA1C) as A1C (percent) + [4 x insulin dose (units per kilogram per 24 h)]. A calculated IDAA1C < or =9 corresponding to a predicted stimulated C-peptide >300 pmol/l was used to define partial remission. The IDAA1C < or =9 had a significantly higher agreement (P < 0.001) with residual beta-cell function than use of a definition of A1C < or =7.5%. Between 6 and 12 months after diagnosis, for IDAA1C < or =9 only 1 patient entered partial remission and 61 patients ended partial remission, for A1C < or =7.5% 15 patients entered partial remission and 53 ended, for a definition of insulin dose < or =0.5 units . kg(-1) . 24 h(-1) 5 patients entered partial remission and 66 ended, and for stimulated C-peptide (>300 pmol/l) 9 patients entered partial remission and 49 ended. IDAA1C at 6 months has good predictive power for stimulated C-peptide concentrations after both 6 and 12 months. CONCLUSIONS A new definition of partial remission is proposed, including both glycemic control and insulin dose. It reflects residual beta-cell function and has better stability compared with the conventional definitions.

Insulin sensitivity in Type 1 diabetic children and adolescents

AIM

To estimate insulin sensitivity in Type 1 diabetic children and adolescents, and assess the relationship between insulin sensitivity and clinical markers of adiposity and parameters of the metabolic syndrome.

METHODS

A total of 202 patients aged 8-18 years with Type 1 diabetes and disease duration 1.5-15 years participated. Insulin sensitivity was estimated by glucose uptake during an euglycaemic-hyperinsulinaemic clamp and was calculated as the average amount of glucose (M(lbm) = mg/kg(lbm)/min) required to maintain euglycaemia. Blood pressure, glycated haemoglobin (HbA(1c)) and lipid concentrations were measured.

RESULTS

The M(lbm )value ranged from 4.14 to 25.25 mg/kg(lbm)/min (mean 9.81 +/- 3.34 mg/kg(lbm)/min). There was a significant relationship between M value and patients' age (r = -0.38, P < 0.0001). Insulin sensitivity decreased significantly with the onset of puberty; hence, it was significantly lower in pubertal and post-pubertal adolescents. Girls were significantly more insulin resistant than boys (9.01 +/- 0.32 vs. 10.43 +/- 0.29 mg/kg(lbm)/min, P = 0.005). Insulin sensitivity correlated with body mass index (r = -0.29, P < 0.001), waist circumference (r = -0.35, P < 0.001), triceps skin fold (r = -0.17, P = 0.018), subscapular skin fold (r = -0.23, P = 0.001) and body fat (r = -0.19, P = 0.006). There was a relationship between M(lbm) value, cholesterol (r = -0.18, P = 0.012), high-density lipoprotein cholesterol (r = 0.15, P = 0.035), low-density lipoprotein cholesterol (r = -0.22, P = 0.002), triglycerides (r = -0.32, P < 0.001) and systolic blood pressure (r = -0.15, P = 0.029). Insulin resistance was related to HbA(1c) (r = -0.18, P = 0.012). Additionally, there was a correlation between M(lbm) value and insulin dose.

CONCLUSIONS

Children and adolescents with Type 1 diabetes mellitus have a very wide range of insulin sensitivity, which is determined by sex, age, amount of adipose tissue and glycaemic control.

Dynamic changes in CD4+ CD25+(high) T cell apoptosis after the diagnosis of type 1 diabetes

Because type 1 diabetes (T1D) is a chronic, autoimmune, T cell-mediated disease, interventions affecting T cells are expected to modulate the immune cascade and lead to disease remission. We propose that increased CD4(+) CD25(+high) T cell apoptosis, a trait we discovered in recent-onset T1D subjects, reflects T1D partial remission within the first 6 months after diagnosis. Apoptosis of forkhead box P3 (FoxP3)(+) CD4(+) CD25(+high) T cells, in addition to total daily doses of insulin (TDD), blood glucose, HbA1c and age, were measured in 45 subjects with T1D at various times after diagnosis. Sixteen healthy control subjects were also recruited to the study. Higher CD4(+) CD25(+high) T cell apoptosis levels were detected within the first 6 months of diagnosis (odds ratio = 1.39, P = 0.009), after adjustment for age, TDD and HbA1c. A proportional hazards model confirmed that the decline of apoptosis after diagnosis of T1D was related significantly to survival time (hazards ratio = 1.08, P = 0.014), with TDD and age also contributing to survival. During this time there was an inverse relationship between CD4(+) CD25(+high) T cell apoptosis with TDD (r = -0.39, P = 0.008). The CD4(+) CD25(+high) T cell apoptosis levels decline significantly after the first 6 months from diagnosis of T1D and may help in the close monitoring of autoimmunity. In parallel, there is an increase in TDD during this time. We also propose that CD4(+) CD25(+high) T cell apoptosis assay can be used to gauge the efficacy of the several immune tolerance induction protocols, now under way.

Association of immune mediators at diagnosis of Type 1 diabetes with later clinical remission

AIMS

We tested the hypothesis that systemic concentrations of cytokines, chemokines or soluble cytokine receptors predict or accompany clinical remission in Type 1 diabetes (T1D).

METHODS

In a prospective, multicentre study, 48 patients with newly diagnosed T1D and 55 age-matched healthy control subjects were investigated. Blood was drawn 3-7 days after the diagnosis and then 3-4 months later. Patients were grouped into partial remitters or non-remitters by the degree of clinical improvement defined by HbA(1c) (threshold 7.5%) and daily insulin dose (threshold 0.38 IU/kg/day). Systemic concentrations of 17 immune mediators were analysed in serum or plasma. In addition, autoantibodies against insulin (IAA), IA-2 (IA-2A) and GAD65 (GADA) were quantified.

RESULTS

All 17 immune mediators showed remarkable intra-individual stability in their systemic concentrations over time. As a consequence, partial remission was not accompanied by changes in mediator levels except for a moderate decrease of interleukin (IL)-1ra concentrations (P = 0.02) and IL-10 concentrations (P = 0.01) in non-remitters. Baseline levels were associated with the later clinical course in that low levels of interferon gamma (P = 0.01), IL-10 (P = 0.03) and IL-1R1 (P = 0.009) concentrations were observed in partial remitters.

CONCLUSIONS

We conclude that the systemic immunoregulatory state at diagnosis of T1D is predictive of clinical improvement during the remission phase. There was no general change in systemic immune reactivity in the months after diagnosis and initiation of insulin therapy.

'The honeymoon phase' in children with type 1 diabetes mellitus: frequency, duration, and influential factors

BACKGROUND

The honeymoon period (i.e., partial remission) of type 1 diabetes mellitus is characterized by reduced insulin requirements while good glycemic control is maintained. The clinical significance is the potential possibility for pharmacological intervention during this period to either slow down or arrest the ongoing destruction of the remaining beta-cells.

METHODS

A group of 103 diabetic children, younger than 12 yr of age, were prospectively studied to assess the frequency, duration, and factors that may affect partial remission. At the time of admission, patients were characterized by age, gender, symptom duration, diabetic ketoacidosis (DKA), and blood sugar level at admission. The honeymoon period was defined as a period with insulin requirements of less than 0.5 U/kg/day and hemoglobin A1c (HbA1c) level of less or equal to 6%.

RESULTS

Partial remission occurred in 71, being complete in three. The length of time until remission was 28.6 +/- 12.3 (mean +/- SD) days. The duration of remission was 7.2 +/- 4.8 months. Remission rates were higher in those patients older than 5 yr compared with those between 3 and 5 yr of age. DKA at presentation and long duration of symptoms were associated with lower duration of remission (p < 0.001 and p < 0.001, respectively). Children in whom remission occurred had significantly lower blood glucose levels and higher pH at presentation (p < 0.001 and p < 0.001, respectively).

CONCLUSIONS

Young age and severe disease at presentation are associated with decreased residual beta-cells function that is reflected by a lower incidence of partial remission. These observations are important to consider in the research regarding therapies that will have the potential goal to induce prolonged and/or complete remission at disease onset or shortly thereafter.

Natural history of beta-cell function in type 1 diabetes

Despite extensive and ongoing investigations of the immune mechanisms of autoimmune diabetes in humans and animal models, there is much less information about the natural history of insulin secretion before and after the clinical presentation of type 1 diabetes and the factors that may affect its course. Studies of insulin production previously published and from the Diabetes Prevention Trial (DPT)-1 suggest that there is progressive impairment in insulin secretory responses but the reserve in response to physiological stimuli may be significant at the time of diagnosis, although maximal responses are more significantly impaired. Other factors, including insulin resistance, may play a role in the timing of clinical presentation along this continuum. The factors that predict the occurrence and rapidity of decline in beta-cell function are still largely unknown, but most studies have identified islet cell autoantibodies as predictors of future decline and age as a determinant of residual insulin production at diagnosis. Historical as well as recent clinical experience has emphasized the importance of residual insulin production for glycemic control and prevention of end-organ complications. Understanding the modifiers and predictors of beta-cell function would allow targeting immunological approaches to those individuals most likely to benefit from therapy.

Insulin secretion in type 1 diabetes

Type 1 diabetes, a chronic autoimmune disease, causes destruction of insulin-producing beta-cells over a period of years. Although many markers of the autoimmune process have been described, none can convincingly predict the rate of disease progression. Moreover, there is relatively little information about changes in insulin secretion in individuals with type 1 diabetes over time. Previous studies document C-peptide at a limited number of time points, often after a nonphysiologic stimulus, and under non-steady-state conditions. Such methods do not provide qualitative information and may not reflect physiologic responses. We have studied qualitative and quantitative insulin secretion to a 4-h mixed meal in 41 patients with newly diagnosed type 1 diabetes and followed the course of this response for 24 months in 20 patients. Newly diagnosed diabetic patients had an average total insulin secretion in response to a mixed meal that was 52% of that in nondiabetic control subjects, considerably higher than has been described previously. In diabetic patients there was a decline of beta-cell function at an average rate of 756 +/- 132 pmol/month to a final value of 28 +/- 8.4% of initial levels after 2 years. There was a significant correlation between the total insulin secretory response and control of glucose, measured by HbA(1c) (P = 0.003). Two persistent patterns of insulin response were seen depending on the peak insulin response following the oral meal. Patients with an early insulin response (i.e., within the first 45 min after ingestion) to a mixed meal, which was also seen in 37 of 38 nondiabetic control subjects, had a significantly accelerated loss of insulin secretion, as compared with those in whom the insulin response occurred after this time (P < 0.05), and significantly greater insulin secretory responses at 18 and 24 months (P < 0.02). These results, which are the first qualitative studies of insulin secretion in type 1 diabetes, indicate that the physiologic metabolic response is greater at diagnosis than has previously been appreciated, and that the qualitative insulin secretory response is an important determinant of the rate of metabolic decompensation from autoimmune destruction.