Factors affecting and patterns of residual insulin secretion during the first year of type 1 (insulin-dependent) diabetes mellitus in children

Predictors of glycemic control in children and adolescents with type 1 diabetes at 12 months after diagnosis

Identifying risk factors for suboptimal glycemic control during the first year after diagnosis with type 1 diabetes (T1D) may provide early appropriate and individualized management. Our aim was to study possible predictors of early glycemic control during the first year after diagnosis with T1D in children and adolescents in Jordan. This is a retrospective study conducted through a review of medical records at Jordan University Hospital and the National Centre for Diabetes, Endocrinology and Genetics. Children and adolescents diagnosed with T1D at age younger than 16 years and with diabetes duration of at least 2 years were included. Demographic, clinical and socioeconomic factors were collected, in addition to glycosylated hemoglobin (HbA1c) values during the first year after diagnosis. Average age at diagnosis of the 337 patients who were enrolled in the study was 7.7 ± 3.8 years. HbA1c at diagnosis was 10.9 ± 1.9% (95.64 ± 20.76 mmol/mol). Factors such as the involvement of children's mothers in deciding insulin doses, higher mother's educational level and higher family monthly income were associated with better early glycemic control. HbA1c at 6 months after diagnosis, parental marital status and compliance to counting carbohydrates were significant predictors of glycemic control at 12 months after diagnosis. Many clinical and socioeconomic factors were associated with early glycemic control at 12 months after diagnosis. Modifiable risk factors must be addressed as early as possible to decrease future complications. Children with nonmodifiable risk factors should be identified early for closer observation and providing individualized diabetes care plan.

CTLA4-Ig (abatacept): a promising investigational drug for use in type 1 diabetes

Introduction: Type 1 diabetes (T1D) is an autoimmune disease that results from the destruction of insulin-producing beta cells in the pancreas; it leads to the under or nonproduction of insulin. T1D is associated with numerous life-threatening micro- and macro-vascular complications and early deaths, hence the development of preventative strategies is a priority for research.Areas covered: The authors outline the drawbacks of available treatments for T1D and assess the three key strategies for prevention, including immunomodulatory therapies which hold the most potential. This article examines CTLA4-Ig and its efficacy and safety profiles. Finally, the pharmacokinetic parameters and pharmacodynamic markers of abatacept are shown in vivo and in clinical trials, guiding dosage regimen recommendations for future investigational studies.Expert opinion: Immunomodulation is one of the promising strategies for decelerating the progression of beta-cell destruction after the onset of T1D. It holds the advantage of specific immune modulation without systemic general immunosuppression. Preclinical and clinical studies have yielded promising data on the use of CTLA4-Ig in T1D. Variations in response to CTLA4-Ig might be partially explained by the existence of multiple T1D subtypes with varying baseline innate inflammatory/regulatory bias and the rate of C-peptide decline.

Increasing prevalence of diabetic ketoacidosis at diabetes diagnosis among children in Quebec: a population-based retrospective cohort study

BACKGROUND

Diabetic ketoacidosis at type 1 diabetes diagnosis is a preventable life-threatening complication. Canadian data on the temporal trends of the prevalence of diabetic ketoacidosis at the onset of type 1 diabetes in children are unknown. We aimed to determine the temporal changes in diabetic ketoacidosis prevalence at diabetes diagnosis in Quebec.

METHODS

We conducted a population-based cohort study of children (aged 1-17 yr) living in Quebec who were diagnosed with diabetes between 2001 and 2014, using multiple health administrative linked databases available at the Institut national de santé publique du Québec through the Quebec Integrated Chronic Surveillance System. We used multivariate Poisson regression analysis with robust error variance to determine trends in the prevalence of diabetic ketoacidosis.

RESULTS

We found that 25.6% (1471/5741) of children presented with diabetic ketoacidosis at diabetes diagnosis. The incidence of diabetes was stable at 30 cases per 100 000 children per year during the study period. The age- and sex-standardized rates of diabetic ketoacidosis increased from 22% (95% confidence interval [CI] 17%-26%) in 2001 to 30% (95% CI 24%-36%) in 2014. The relative increase of diabetic ketoacidosis prevalence at diabetes diagnosis over the study period was 2.0% per year (rate ratio 1.02; 95% CI 1.01-1.03).

INTERPRETATION

Despite a stable incidence of type 1 diabetes, we found that the prevalence of diabetic ketoacidosis at diabetes onset increased between 2001 and 2014. Our findings are concerning and demonstrate a need to continue to campaign to recognize type 1 diabetes before diabetic ketoacidosis supervenes.

Persistent elevations in circulating INS DNA among subjects with longstanding type 1 diabetes

AIM

To evaluate whether β cells continue to undergo death in the later stages of type 1 diabetes (T1D).

MATERIALS AND METHODS

Fasting banked sera from a cross-section of 90 participants in the T1D Exchange Registry with longstanding T1D (median duration of 9 years) were analysed. Subjects were determined to be C-peptide (-) or (+) based on mixed-meal tolerance testing. Results were compared with 54 adult non-diabetic controls. Stimulated samples were assayed in a subset of subjects. Levels of unmethylated and methylated preproinsulin (INS) DNA were analysed using digital droplet PCR.

RESULTS

Fasting and stimulated circulating unmethylated INS DNA levels were increased among both C-peptide (-) and C-peptide (+) subjects with longstanding T1D compared with non-diabetic controls (P < 0.01). Consistent with prior reports, unmethylated INS DNA values correlated with methylated INS DNA values, which were also elevated among T1D subjects (P < 0.001). There was wide variation in the effects of mixed-meal stimulation on DNA levels, with fasting values in the highest quartiles decreasing with stimulation (P < 0.05).

CONCLUSIONS

These results could reflect ongoing β cell death in individuals with longstanding T1D, even in the absence of detectable C-peptide production, suggesting that therapies targeting β cell survival could be beneficial among individuals with longstanding T1D.

Predictors of glycemic control in the first year of diagnosis of childhood onset type 1 diabetes: A systematic review of quantitative evidence

Early glycemic control is associated with reduced future vascular complications risk in type 1 diabetes (T1D). The aim of this study was to systematically review evidence on the predictors of glycemic control within 12 months of diagnosis of childhood onset T1D. Inclusion criteria for the electronic search were: interventional and observational studies that assessed and quantified an association between the predictor and glycemic control within 12 months of diagnosis of childhood onset T1D. A total of 17 915 articles were identified from 6 databases and 20 studies were finally included in the analysis. Harvest plots and narrative synthesis were used to summarize data from intervention (n = 0), prospective/retrospective cohort (n = 15), and cross-sectional (n = 5) studies. Significant predictors of poorer glycemic control 0 to 3 months after diagnosis were older age and female gender. Non-white ethnicity, diabetes autoantibody positivity, measures of deprivation, and non-private health insurance were potential predictors. Predictors of poorer glycemic control 4 to 12 months after diagnosis were: older age, non-white ethnicity, a single parent family, high hemoglobin A1c (HbA1c) levels at diagnosis, longer T1D duration, and non-intensive insulin therapy. Potential predictors included: family with health issues, clinical factors, and comorbidities at diagnosis. Most significant predictors of poor glycemic control within 12 months of diagnosis of childhood onset T1D are non-modifiable. These factors need to be recognized and addressed through individualized and multidisciplinary diabetes care. Further research is required to confirm the association of potential predictors with early glycemic control.

Integration of Routine Parameters of Glycemic Variability in a Simple Screening Method for Partial Remission in Children with Type 1 Diabetes

Although different criteria were used to define partial remission in type 1 diabetes, the IDAA1C formula has prevailed as it correlates with stimulated C-peptide levels. Our retrospective study evaluated clinical variables associated with the occurrence of IDAA1C-defined partial remission in a series of 239 pediatric patients. Diabetic ketoacidosis and age at diagnosis, but no other clinical feature, influenced the occurrence of remission. We then evaluated whether parameters of glycemic variability used in clinical routine may reliably define partial remission, as these would alleviate confounding factors related to insulin treatment. Using multiple linear regression, we observed that HbA_1C levels and percentage of normoglycemia were efficient and sufficient to predict partial remission. These parameters were entered into a formula, called glycemic target-adjusted HbA_1C (GTAA_1C), that corresponded to HbA_1C(%) - (3 × % of normoglycemic values_{(70-180 mg/dL)}). With a threshold of 4.5, this alternative formula predicted partial remission with a sensitivity and a specificity of 72.3% and 92%, respectively, and yielded strong correlation with IDAA1C levels and BETA-2 score, which is a correlate of β-cell function after islet transplantation. We propose GTAA_1C, based on routine and objective markers of glycemic variability, as a valid alternative for definition of partial remission in type 1 diabetes.

Factors Associated with C-peptide Levels after Diagnosis in Children with Type 1 Diabetes Mellitus

C-peptide is the best indicator of endogenous insulin secretion in patients with diabetes. This study investigated the relationship between C-peptide levels and clinical/laboratory parameters of children with type 1 diabetes mellitus (T1DM), as measured at 6-month intervals after diagnosis. We retrospectively reviewed the data of 34 children with newly diagnosed T1DM. The study subjects were subdivided into a rapid progression group with C-peptide levels <0.6 ng/mL at 36 months (n=27; Group A) and a slow progression group with C-peptide levels >0.6 ng/mL at 36 months (n=7; Group B). Patients in Group A had a younger mean age at diagnosis (A: 9±4.3 years vs. B: 13.6±3.6 years; p=0.013) and lower body mass index (BMI) (A: 15.5±2.5 kg/m² vs. B: 18.7±3.3 kg/m²; p=0.035). There were fewer asymptomatic patients with glucosuria in Group A, with these patients showing more severe symptoms, such as diabetic ketoacidosis (p=0.035), than those in Group B. Group A also had lower initial C-peptide levels (A: 0.5±0.46 ng/mL vs. B: 1.87±1.08 ng/mL; p=0.001). There were no significant intergroup differences in sex, family history, baseline hemoglobin A1c (HbA1c), potential of hydrogen (pH), autoantibodies or serum insulin. Simple correlation analyses showed that C-peptide levels were correlated with age and BMI, but not with pH, insulin, or HbA1c. Younger patients, who had a lower BMI, significant symptoms with complications, and/or a low initial C-peptide level, tended to show a rapid rate of decrease in C-peptide levels. Early intensive insulin therapy to preserve beta-cell function should be considered in these groups.

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.

CGM-measured glucose values have a strong correlation with C-peptide, HbA1c and IDAAC, but do poorly in predicting C-peptide levels in the two years following onset of diabetes

AIMS/HYPOTHESIS

The aim of this work was to assess the association between continuous glucose monitoring (CGM) data, HbA1c, insulin-dose-adjusted HbA1c (IDAA1c) and C-peptide responses during the first 2 years following diagnosis of type 1 diabetes.

METHODS

A secondary analysis was conducted of data collected from a randomised trial assessing the effect of intensive management initiated within 1 week of diagnosis of type 1 diabetes, in which mixed-meal tolerance tests were performed at baseline and at eight additional time points through 24 months. CGM data were collected at each visit.

RESULTS

Among 67 study participants (mean age [± SD] 13.3 ± 5.7 years), HbA1c was inversely correlated with C-peptide at each time point (p < 0.001), as were changes in each measure between time points (p < 0.001). However, C-peptide at one visit did not predict the change in HbA1c at the next visit and vice versa. Higher C-peptide levels correlated with increased proportion of CGM glucose values between 3.9 and 7.8 mmol/l and lower CV (p = 0.001 and p = 0.02, respectively) but not with CGM glucose levels <3.9 mmol/l. Virtually all participants with IDAA1c < 9 retained substantial insulin secretion but when evaluated together with CGM, time in the range of 3.9-7.8 mmol/l and CV did not provide additional value in predicting C-peptide levels.

CONCLUSIONS/INTERPRETATION

In the first 2 years after diagnosis of type 1 diabetes, higher C-peptide levels are associated with increased sensor glucose levels in the target range and with lower glucose variability but not hypoglycaemia. CGM metrics do not provide added value over the IDAA1c in predicting C-peptide levels.

Preserved C-peptide levels in overweight or obese compared with underweight children upon diagnosis of type 1 diabetes mellitus

PURPOSE

We hypothesized that overweight or obese children might develop type 1 diabetes mellitus (T1DM) early despite residual beta-cell function. Factors independently associated with preservation of C-peptide level were analyzed.

METHODS

We retrospectively reviewed the medical data of 135 children aged 2.1-16.5 years with autoimmune T1DM. Body mass index (BMI), pubertal stage, and glycosylated hemoglobin (HbA1c) and C-peptide levels were evaluated. Patients were assigned to underweight (22.2%), normal weight (63.7%), and overweight or obese (14.1%) groups according to their BMI.

RESULTS

Preservation of serum C-peptide levels (≥0.6 ng/mL) was found in 43.0% of subjects. With increasing BMI, the proportions of children with preserved C-peptide levels increased from 33.3% to 41.9% to 63.2%, with marginal significance (P=0.051). Interaction analysis indicated no effect of BMI score on age at onset associated with serum C-peptide levels. The lower the C-peptide level, the younger the age of onset (P<0.001), after adjustment for BMI z-score and HbA1c level. However, no significant relationship between BMI z-score or category and onset age was evident. Upon multivariate-adjusted modeling, the odds that the C-peptide level was preserved increased by 1.2 fold (P=0.001) per year of life, by 3.1 folds (P=0.015) in children presenting without (compared to with) ketoacidosis, and by 5.0 folds (P=0.042) in overweight or obese (compared to underweight) children.

CONCLUSION

Overweight or obese children had slightly more residual beta-cell function than did underweight children. However, we found no evidence that obesity temporally accelerates T1DM presentation.

Pediatric Diabetes Consortium Type 1 Diabetes New Onset (NeOn) Study: factors associated with HbA1c levels one year after diagnosis

OBJECTIVE

To identify determinants of hemoglobin A1c (HbA1c) levels 1 yr after the diagnosis of type 1 diabetes (T1D) in participants in the Pediatric Diabetes Consortium (PDC) T1D New Onset (NeOn) Study.

RESEARCH DESIGN AND METHODS

Diabetes-specific as well as socioeconomic factors during the first year following diagnosis were analyzed in 857 participants (mean age 9.1 yrs, 51% female, 66% non-Hispanic White) not participating in an intervention study who had an HbA1c value at 12 months.

RESULT

Mean ± SD HbA1c at 1 yr was 62 ± 16 mmol/mol (7.8% ± 1.5). In univariate and multivariate analyses, clinical center, non-Hispanic White race, private health insurance, living with both parents, higher frequency of self-monitoring of blood glucose (SMBG), and lower insulin requirements were associated with lower HbA1c concentrations at 1 yr (p < 0.01). No association was found with gender, age, Tanner stage, body mass index (BMI), diabetic ketoacidosis (DKA) at onset, number of positive autoantibodies or HbA1c at onset, or number of visits to diabetes physician during the first year.

CONCLUSIONS

White race, higher socioeconomic status, two-parent household, more frequent SMBG, and low insulin requirements are associated with lower HbA1c concentration 1 yr after the onset of T1D in children.

Smoking and other factors associated with short-term partial remission of Type 1 diabetes in adults

AIMS

The duration of partial remission of Type 1 diabetes is associated with the degree of initial metabolic disturbance and features of insulin resistance. Cigarette smoking decreases insulin sensitivity, but its influence on the length of remission is unknown. Therefore, this study assessed the relationship between cigarette smoking and duration of partial remission in adults with newly diagnosed Type 1 diabetes.

METHODS

We recruited 149 patients (48 women and 101 men, aged 16-35 years, median age 25 years), admitted to a teaching hospital with newly diagnosed Type 1 diabetes and followed them for a median period of 1 year and 9 months. We introduced intensive insulin therapy in multiple injections (basal-bolus) in all patients. We defined partial remission as an insulin dose of ≤ 0.3 U/kg body weight/24 h, an HbA(1c) value < 53 mmol/mol (7.0%) and a random serum C-peptide concentration over 0.5 ng/ml. Cigarette smoking was determined by self-report.

RESULTS

Of 149 patients, 68 (46%) fulfilled the criteria for partial remission at 1 year after diagnosis of diabetes. Fewer patients who were in partial remission at 1 year smoked (19/68, 28%) than did patients that were not in partial remission (41/81, 51%). In logistic regression analyses, non-smoking was associated with remission at 1 year independent of age, sex, HbA(1c) and presence of diabetic ketoacidosis, all measured at onset of diabetes (OR 3.32, 95% CI 1.42-7.75, P = 0.005).

CONCLUSION

Relative to individuals in this study who smoked, those who did not smoke at diagnosis of Type 1 diabetes experienced a longer duration of partial remission.

Persistence of prolonged C-peptide production in type 1 diabetes as measured with an ultrasensitive C-peptide assay

OBJECTIVE

To examine persistence of C-peptide production by ultrasensitive assay years after onset of type 1 diabetes and factors associated with preserving β-cell function.

RESEARCH DESIGN AND METHODS

Serum C-peptide levels, a marker of insulin production and surviving β-cells, were measured in human subjects (n = 182) by ultrasensitive assay, as was β-cell functioning. Twenty-two times more sensitive than standard assays, this assay's lower detection limit is 1.5 pmol/L. Disease duration, age at onset, age, sex, and autoantibody titers were analyzed by regression analysis to determine their relationship to C-peptide production. Another group of four patients was serially studied for up to 20 weeks to examine C-peptide levels and functioning.

RESULTS

The ultrasensitive assay detected C-peptide in 10% of individuals 31-40 years after disease onset and with percentages higher at shorter duration. Levels as low as 2.8 ± 1.1 pmol/L responded to hyperglycemia with increased C-peptide production, indicating residual β-cell functioning. Several other analyses showed that β-cells, whose C-peptide production was formerly undetectable, were capable of functioning. Multivariate analysis found disease duration (β = -2.721; P = 0.005) and level of zinc transporter 8 autoantibodies (β = 0.127; P = 0.015) significantly associated with C-peptide production. Unexpectedly, onset at >40 years of age was associated with low C-peptide production, despite short disease duration.

CONCLUSIONS

The ultrasensitive assay revealed that C-peptide production persists for decades after disease onset and remains functionally responsive. These findings suggest that patients with advanced disease, whose β-cell function was thought to have long ceased, may benefit from interventions to preserve β-cell function or to prevent complications.

Prevention of type 1 diabetes

Prevention of loss of b cells in type 1 diabetes is a major goal of current research. Knowledge of the genetic susceptibility, increasing ability to predict who may be at risk, recognition of the potential clinical impact of residual insulin secretion after diagnosis, and development of new immunomodulatory agents have supported an increasing number of clinical trials to prevent b-cell loss. Interventions can be targeted at 3 stages: before the development of autoimmunity (primary prevention), after autoimmunity is recognized (secondary prevention), or after diagnosis when significant numbers of b cells remain (tertiary prevention). Thus far, several agents show promise when given shortly after diagnosis, but no interventions before diagnosis have shown benefit. Knowledge in this area has grown quickly in recent years and will continue to grow rapidly with several international collaborative efforts underway.

Factors associated with the presence of diabetic ketoacidosis at diagnosis of diabetes in children and young adults: a systematic review

OBJECTIVE

To identify the factors associated with diabetic ketoacidosis at diagnosis of type 1 diabetes in children and young adults.

DESIGN

Systematic review.

DATA SOURCES

PubMed, EMBASE, Web of Science, Scopus, and Cinahl and article reference lists.

STUDY SELECTION

Cohort studies including unselected groups of children and young adults presenting with new onset type 1 diabetes that distinguished between those who presented in diabetic ketoacidosis and those who did not and included a measurement of either pH or bicarbonate in the definition of diabetic ketoacidosis. There were no restrictions on language of publication.

RESULTS

46 studies involving more than 24,000 children in 31 countries were included. Together they compared 23 different factors. Factors associated with increased risk were younger age (for <2 years old v older, odds ratio 3.41 (95% confidence interval 2.54 to 4.59), for <5 years v older, odds ratio 1.59 (1.38 to 1.84)), diagnostic error (odds ratio 3.35 (2.35 to 4.79)), ethnic minority, lack of health insurance in the US (odds ratio 3.20 (2.03 to 5.04)), lower body mass index, preceding infection (odds ratio 3.14 (0.94 to 10.47)), and delayed treatment (odds ratio 1.74 (1.10 to 2.77)). Protective factors were having a first degree relative with type 1 diabetes at the time of diagnosis (odds ratio 0.33 (0.08 to 1.26)), higher parental education (odds ratios 0.4 (0.20 to 0.79) and 0.64 (0.43 to 0.94) in two studies), and higher background incidence of type 1 diabetes (correlation coefficient -0.715). The mean duration of symptoms was similar between children presenting with or without diabetic ketoacidosis (16.5 days (standard error 6.2) and 17.1 days (6.0) respectively), and up to 38.8% (285/735) of children who presented with diabetic ketoacidosis had been seen at least once by a doctor before diagnosis.

CONCLUSIONS

Multiple factors affect the risk of developing diabetic ketoacidosis at the onset of type 1 diabetes in children and young adults, and there is potential time, scope, and opportunity to intervene between symptom onset and development of diabetic ketoacidosis for both parents and clinicians.

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.

Beta-cell autoantibodies and their function in Taiwanese children with type 1 diabetes mellitus

BACKGROUND/PURPOSE

To understand the importance of autoimmunity in the development of type 1 diabetes in Taiwanese children, we evaluated the presence of beta-cell autoantibodies and their correlation with residual beta-cell function.

METHODS

From 1989 to 2006, 157 Taiwanese children with newly diagnosed type 1 diabetes were enrolled in this study. We determined the presence of beta-cell autoantibodies, such as glutamic acid decarboxylase autoantibodies (GADAs), insulinoma antigen 2 autoantibodies (IA-2As), and insulin autoantibodies (IAAs). A 6-minute glucagon test was also performed at diagnosis.

RESULTS

At diagnosis, 73% of children tested positive for GADAs, 76% for IA-2As and 21% for IAAs. Ninety-two percent of them had at least one of the beta-cell autoantibodies detected. Positivity for IAAs was more frequent in patients younger than 5 years than in those older than 5 years (45% vs. 13%). Using multiple regression analysis, the presence of GADAs or IAAs, or age of onset of these patients was an independent factor for residual beta-cell function. Younger patients and those with GADAs had less residual beta-cell function at disease onset, whereas those with IAAs had more insulin reserve.

CONCLUSION

Autoimmunity plays an important role in the pathogenesis of type 1 diabetes in Taiwanese children, and the presence of IAAs tends to be more common in younger children.

Review: The importance of residual endogenous beta-cell preservation in type 1 diabetes

Achieving tight glycaemic control in type 1 diabetes remains very challenging for patients. However, some individuals retain a degree of endogenous beta-cell function for 5 or more years after diagnosis, and prospective studies confirm that this is associated not only with lower glycated haemoglobin A1c levels, and less hypoglycaemia, but also a reduced incidence of long-term complications. An independent effect of insulin C-peptide may contribute to this beneficial effect. Retention of even small amounts of endogenous beta-cell function for as long as possible should therefore be a key therapeutic goal in type 1 diabetes. Tight glycaemic control from diagnosis has already been shown to help in this regard, and we argue that the introduction of novel immunotherapies which achieve this important goal should be strongly encouraged, even if they fall short of an insulin-free 'cure'.

Prevention of type 1 diabetes

Prevention of loss of beta cells in type 1 diabetes is a major goal of current research. Knowledge of the genetic susceptibility, increasing ability to predict who may be at risk, recognition of the potential clinical impact of residual insulin secretion after diagnosis, and development of new immunomodulatory agents have supported an increasing number of clinical trials to prevent beta-cell loss. Interventions can be targeted at 3 stages: before the development of autoimmunity (primary prevention), after autoimmunity is recognized (secondary prevention), or after diagnosis when significant numbers of beta cells remain (tertiary prevention). Thus far, several agents show promise when given shortly after diagnosis, but no interventions before diagnosis have shown benefit. Knowledge in this area has grown quickly in recent years and will continue to grow rapidly with several international collaborative efforts underway.

Preservation of beta-cell function in autoantibody-positive youth with diabetes

OBJECTIVE

To determine the extent of beta-cell function in youth with diabetes and GAD65 and/or IA2 autoantibodies.

RESEARCH DESIGN AND METHODS

Fasting C-peptide levels from 2,789 GAD65- and/or IA2 autoantibody-positive youth aged 1-23 years from the SEARCH for Diabetes in Youth study were used. Preserved beta-cell function was defined on the basis of cut points derived from the Diabetes Control and Complications Trial (DCCT) (fasting C-peptide > or =0.23 ng/ml) and from the U.S. adolescent population of the National Health and Nutrition Examination Survey (NHANES) 5th percentile for fasting C-peptide (> or =1.0 ng/ml). We compared the clinical characteristics between those with and without preserved beta-cell function.

RESULTS

Within the first year of diagnosis, 82.9% of youth had a fasting C-peptide > or =0.23 ng/ml and 31.2% had values > or =1.0 ng/ml. Among those with > or =5 years of diabetes duration, 10.7% had preserved beta-cell function based on the DCCT cutoff and 1.0% were above the 5th percentile of the NHANES population.

CONCLUSIONS

Within the 1st year of diagnosis, four of five youth with autoantibody-positive diabetes have clinically significant amounts of residual beta-cell function and about one-third have fasting C-peptide levels above the 5th percentile of a healthy adolescent population. Even 5 years after diagnosis, 1 of 10 has fasting C-peptide above a clinically significant threshold. These findings have implications for clinical classification of youth with diabetes as well as clinical trials aimed to preserve beta-cell function after diabetes onset.

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.

Clinical manifestations and beta cell function in Swedish diabetic children have remained unchanged during the last 25 years

BACKGROUND

The incidence of type 1 diabetes in childhood has doubled in Sweden during the last decades. Environmental factors may cause a different disease process, residual beta cell function and clinical manifestation. Insulin therapy has become more intensive. The aim of this study was to examine the clinical characteristics at onset, C-peptide secretion during the first years after diagnosis and if there was any secular trends during the last 25 years.

METHODS

All 316 children diagnosed with type 1 diabetes during 1976--2000 and living in the Linköping area were included. Information about clinical characteristics at diagnosis, duration of partial remission, insulin therapy at diagnosis and during the first years was collected from medical records. C-peptide secretion (fasting and stimulated) was measured regularly during the first 5 years. For analysis, the population was divided in five cohorts according to the year of diagnosis.

RESULTS

The clinical characteristics at onset were unchanged as well as duration of partial remission. C-peptide secretion was highest after 3 months and then declined gradually. After 5 years 32.7% of the patients had measurable fasting C-peptide, but only 6.5% > 0.1 nmol/L. HbA1c and insulin doses were lower in patients with persistent fasting C-peptide secretion > 0.1 nmol/L. The cohort 1996--2000 had higher stimulated C-peptide secretion at diagnosis and at 3 months, after longer follow-up there was no difference.

CONCLUSION

The clinical characteristics at diagnosis, partial remission and duration of C-peptide secretion have remained largely unchanged for the last 25 years.

Extent of beta cell destruction is important but insufficient to predict the onset of type 1 diabetes mellitus

Background

Type 1 diabetes mellitus is characterized by an inability to produce insulin endogenously. Based on a series of histopathology studies of patients with recent onset of the disease, it is commonly stated that the onset of clinical symptoms corresponds to an 80-95% reduction in beta cell mass. Motivated by the clinical importance of the degree of beta cell destruction at onset, a meta-analysis was used to determine the validity of this common wisdom.

Methods and Findings

The histopathology results identifying insulin containing islets in patients younger than 20 years of age were extracted from three different studies. The results for 105 patients were stratified by duration of diabetic symptoms and age at onset. Linear regression and a non-parametric bootstrap approach were used to determine the dependence of residual beta cell mass to age at onset. The percentage reduction in beta cell mass was highly correlated (p<0.001) with the age of onset with the greatest reduction in beta cell mass in the youngest patients. As this trend had not been previously observed, an alternative physiology-based model is proposed that captures this age-dependence.

Conclusions

The severity in beta cell reduction at onset decreased with age where, on average, a 40% reduction in beta cell mass was sufficient to precipitate clinical symptoms at 20 years of age. The observed trend was consistent with a physiology-based model where the threshold for onset is based upon a dynamic balance between insulin-production capacity, which is proportional to beta cell mass, and insulin demand, which is proportional to body weight.

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.

'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.

Type 1 diabetes

Type 1 diabetes accounts for only about 5-10% of all cases of diabetes; however, its incidence continues to increase worldwide and it has serious short-term and long-term implications. The disorder has a strong genetic component, inherited mainly through the HLA complex, but the factors that trigger onset of clinical disease remain largely unknown. Management of type 1 diabetes is best undertaken in the context of a multidisciplinary health team and requires continuing attention to many aspects, including insulin administration, blood glucose monitoring, meal planning, and screening for comorbid conditions and diabetes-related complications. These complications consist of microvascular and macrovascular disease, which account for the major morbidity and mortality associated with type 1 diabetes. Newer treatment approaches have facilitated improved outcomes in terms of both glycaemic control and reduced risks for development of complications. Nonetheless, major challenges remain in the development of approaches to the prevention and management of type 1 diabetes and its complications.

Glucose evaluation trial for remission (GETREM) in type 1 diabetes: a European multicentre study

OBJECTIVE

Strict metabolic control during the 1st year of type 1 diabetes is thought to be a key factor for achieving clinical remission. The aims of this study were two-fold: (i) to evaluate the frequency and duration of spontaneous remission (defined according to the parameters issued by the International Diabetic Immunotherapy Group (IDIG)) in a European population of consecutive recent onset type 1 diabetes patients (aged 5-35 years), followed-up for a period of 36 months with a common protocol of intensive insulin therapy and without adjunct immune-intervention; and (ii) to identify the predictive factors for clinical remission.

RESEARCH DESIGN AND METHOD

A total of 189 consecutive patients with newly diagnosed type 1 diabetes according to ADA criteria were recruited in participating centres (Belgium, Czech Republic, Estonia, France, Germany, Hungary, Italy, Poland, Romania, Sweden and Turkey) and followed-up for a period of up to 36 months. In all patients, intensive insulin therapy was implemented consisting of three or four injections of regular insulin daily with NPH insulin at bedtime. Adjustment of insulin dose was made according to a common protocol. Various clinical characteristics (age, gender, severity of presentation, etc.), history (presence of diabetic siblings in the family, etc.) and integrated parameters of metabolic control (HbA(1c), blood glucose, the total insulin dose at hospital discharge adjusted for body weight) were collected.

RESULTS

Twenty-two patients (11.6%) experienced remission. The median duration of remission was 9.6 months and the range was 31 months. There was a wide variation among centres. Logistic regression analysis focused on the centre as the main variable in achieving remission.

CONCLUSION

Remission was shown to be very heterogeneous between centres depending on 'other factors' such as patient care and family awareness of the disease rather than on 'measurable factors' such as sex, age, HbA(1c) and severity of presentation at diagnosis. Using intensive insulin therapy and optimisation of metabolic control, remission occurred in nearly one out of eight patients.

The severity of clinical presentation of type 1 diabetes in children does not significantly influence the pattern of residual beta-cell function and long-term metabolic control

AIM

The purpose of the present study was to compare relationships between the clinical presentation of type 1 diabetes in children and residual beta-cell secretion and long-term metabolic control.

METHODS

This retrospective study was conducted in 66 diabetic children with age at diagnosis ranging from 0.7 to 14.8 yr. The patients showed contrasting characteristics at diagnosis: either diabetic ketoacidosis (DKA) (group 1, n = 29) or absence of metabolic derangement (group 2, n = 37) associated with marked (group 2A, n = 12) or mild hyperglycemia (group 2B, n = 25). A regular follow-up was available for at least 10 yr (10-32 yr) in all cases and for 20 yr in 23 cases. C-peptide levels were measured from diagnosis and thereafter at intervals for the first years of disease until becoming permanently undetectable.

RESULTS

C-peptide levels at diagnosis were undetectable in about 20% of the cases both with and without DKA. C-peptide levels at diagnosis, the duration of measurable C-peptide levels and the maximum value found during follow-up were not significantly different in the three groups and were not correlated with glycated hemoglobin (GHb) calculated throughout the whole period. No differences were found between the groups of patients concerning GHb values and insulin dose at 10, 15 and 20 yr of disease. The patients of group 2A, characterized by an extremely high glycemic level without ketoacidosis, had a significantly higher prevalence of HLA DR3/4 heterozygosity.

CONCLUSIONS

The severity of clinical presentation at diagnosis does not significantly influence residual beta-cell function, and long-term metabolic control.

Glutamic acid decarboxylase and ICA512/IA-2 autoantibodies as disease markers and relationship to residual beta-cell function and glycemic control in young type 1 diabetic patients

Circulating autoantibodies (Ab) to islet autoantigens, glutamic acid decarboxylase (GAD(65)), and tyrosine phosphatase ICA512/IA-2 have been proposed as predictive markers of type 1 diabetes mellitus. To ascertain residual beta-cell function and the clinical relevance for monitoring autoimmunity after clinical manifestation of disease, we studied 63 children at diagnosis of type 1 diabetes (mean SD age 7.5 +/- 4 years) and 91 adolescent patients with type 1 diabetes (age 14.7 +/- 1.6 years) with a mean duration of disease of 7 +/- 3.5) years. Forty-two normal adolescent subjects (age 14.6 +/- 1.8 years) without a family history of diabetes were the control group. Anti-GAD(65) and ICA512/IA-2 Ab were assessed by a quantitative radioimmunoprecipitation assay. The relationship between humoral autoimmunity and clinical parameters was explored. GAD(65) and ICA512/IA-2 Ab were detected in 56% and 63% of newly diagnosed children and the prevalence was not different in relationship to clinical characteristics. Levels of GAD(65) Ab positively correlated with diagnosis age (P <.05). Both Ab were associated with islet cell antibodies (ICA) (P <.05), but one fifth of patients had at least 1 of the 2 Ab and absent ICA. At onset, only age showed a significant relationship to residual C-peptide secretion. Among the cohort of patients with diabetes of short-mid duration, GAD(65) and ICA512/IA-2 Ab were present in 44% and 45% of cases (P >.05 and P <.05 v newly diagnosed children, respectively) and more patients were identified by these Ab (68%) than by ICA alone (34%) (P <.05). In this cohort, levels of ICA512/IA-2 Ab negatively correlated with levels of glycosylated hemoglobin (HbA(1c)) (P <.005) and with daily insulin requirement (P <.05). Moreover, the presence of some residual C-peptide secretion was significantly associated with the presence of ICA512/IA-2 Ab (P <.05). Our findings confirm that positivity for either GAD(65) or ICA512/IA-2 Ab is a highly sensitive marker of type 1 diabetes in the pediatric age group, identifying a group of patients with absent ICA immunofluorescence. The persistence of Ab to islet tyrosine phosphatase possibly represents a marker of better glycemic control and less insulin requirement, indicating residual beta-cell function, thus conferring clinical and prognostic relevance to these Ab, as well as potential usefulness in intervention strategies.

Type 1 diabetes intervention trials: what have we learned? A critical review of selected intervention trials

Developing therapies to stop or slow the immune destruction of islets has been a goal of investigators in type 1 diabetes for several decades. This review of clinical interventions in patients with type 1 diabetes indicates both negative and positive outcomes with a variety of different therapeutic agents. An underlying theme of this article is that differences in study design may impact the outcome more than the therapy being tested. Thus, each of these results need to be considered in the context of important variables in study design. To date, there is no clear answer as to what study design is best to determine if an agent is effective against the diabetes disease process; however, the Immunology of Diabetes Society has recently developed guidelines for the conduct of these trials to facilitate comparisons of therapies in the future.

Type 1 diabetes mellitus in early childhood: glycemic control and associated risk of hypoglycemic reactions

OBJECTIVE

To assess the level of glycemic control and to determine whether more normal glycemic control, as measured by glycosylated hemoglobin, leads to frequent hypoglycemic episodes in young patients with type 1 diabetes mellitus.

MATERIAL AND METHODS

We undertook a retrospective review of the medical records of 59 children with type 1 diabetes diagnosed at age 9 years or younger, who underwent follow-up at our institution for at least 2 years. For each follow-up, insulin requirements, levels of glycosylated hemoglobin, and frequency of hypoglycemic reactions were analyzed for three age-groups--0 to 2 years, 2 to 5 years, and 5 to 9 years old.

RESULTS

The mean glycosylated hemoglobin for the first 2 years after diagnosis of type 1 diabetes was higher in children 0 to 2 years old in comparison with the other age-groups. This increased glycosylated hemoglobin occurred despite increased administration of insulin, expressed in units per kilogram daily, to these children (P < 0.05). Severe hypoglycemic reactions were more common in infants (55%) and children between 2 and 5 years old (45%) than in children from 5 to 9 years old (13%). In all age-groups, the mean glycosylated hemoglobin value closest to a hypoglycemic event and the mean glycosylated hemoglobin value for the 2-year study period were similar but were both less than 8% (the standard established by the Diabetes Control and Complications Trial). Most reactions had no clear cause in the youngest age-group, whereas a specific reason could usually be determined in children 2 to 5 years old.

CONCLUSION

Tight glycemic control is achievable in young patients with type 1 diabetes mellitus. Such tight control, however, may lead to an increase in the frequency of severe hypoglycemic reactions in this patient population. Our data support the guideline that children younger than 5 years should have a higher goal for premeal plasma glucose levels.

Age governs gender-dependent islet cell autoreactivity and predicts the clinical course in childhood IDDM

Most IDDM patients temporarily restore some of their beta-cell function following the initiation of insulin therapy. The aim of this study was to analyse the influence of age, gender, metabolic state at diagnosis and presence of autoantibodies (GAD65 antibodies and ICA) on the duration of the clinical partial remission. In total, 149 consecutively diagnosed IDDM children, 0-16 y old (70F, 79M, mean age 9.5 y) were studied. Partial remission was arbitrarily defined as the period when the insulin dose was below 0.5 U/BW 24 h-1 and HbA1c below 7.5%, and occurred in 119/149 patients with a duration between 1 and 38 months. Cox's regression analysis showed that the factors significantly associated with the duration of remission were age, gender, interaction between age and gender, ICA and a high initial HbA1c, whereas GAD65Ab had no influence. Young boys had the shortest remission period, while adolescent boys had the longest, as compared to young and adolescent girls. The ICA-negative patients (n = 42) had a longer remission period (median 9.7 months) than the ICA-positive children (n = 107; 5.0 months; p = 0.0001), regardless of GAD65Ab status. We speculate that the relative insulin resistance, which is more pronounced in pubertal girls than in boys, may be associated with a more rapid increase of exogenous insulin requirement. These findings are important when evaluating the effect of islet cell autoreactivity on the clinical course of IDDM in children.

The C-peptide response to a standard mixed meal in a group of Brazilian type 1 diabetic patients

In order to analyze the different parameters used in the interpretation of C-peptide response in a functional test, we compared a group of 26 type 1 diabetics aged 21.1 +/- 8.2 years, with a diabetes duration of 7.9 +/- 6.7 months, with a group of 24 non-diabetic subjects aged 25.0 +/- 4.4 years. A standard mixed meal of 317 kcal was used as a stimulus. Blood sampling for C-peptide determinations was performed at regular intervals. Although all the studied C-peptide variables were significantly lower in the diabetic group (P < 0.0001), some overlapping of parameters was observed between the two groups. The highest degree of overlapping was found for basal value (BV) (30.8%) and percent increase (42.31%), and the lowest for incremental area, absolute increase, peak value (PV) (3.8%), and total area (7.7%) (chi 2 = 31.6, P < 0.0001). We did not observe a definite pattern in the time of maximum response among the 21 diabetics who showed an increase in C-peptide levels after the stimulus. In this group, however, there was a highly significant number of late responses (120 min) (chi 2 = 5.7, P < 0.002). Although BV showed a significant correlation with PV (rS = 0.95, P < 0.0001), the basal levels of C-peptide did not differentiate the groups with and without response to the stimulus. We conclude that the diabetic group studied showed delayed and reduced C-peptide responses, and that the functional test can be an important tool for the evaluation of residual beta cell function.

Ketoacidosis at the diagnosis of type 1 (insulin dependent) diabetes mellitus is related to poor residual beta cell function. Childhood Diabetes in Finland Study Group

The determinants of the degree of metabolic decompensation at the diagnosis of type 1 (insulin dependent) diabetes mellitus (IDDM) and the possible role of diabetic ketoacidosis in the preservation and recovery of residual beta cell function were examined in 745 Finnish children and adolescents. Children younger than 2 years or older than 10 years of age were found to be more susceptible to diabetic ketoacidosis than children between 2 and 10 years of age (< 2 years: 53.3%; 2-10 years: 16.9%; > 10 years: 33.3%). Children from families with poor parental educational level had ketoacidosis more often than those from families with high parental educational level (24.4% v 16.9%). A serum C peptide concentration of 0.10 nmol/l or more was associated with a favourable metabolic situation. Low serum C peptide concentrations, high requirement of exogenous insulin, low prevalence of remission, and high glycated haemoglobin concentrations were observed during the follow up in the group of probands having diabetic ketoacidosis at the diagnosis of IDDM. Thus diabetic ketoacidosis at diagnosis is related to a decreased capacity for beta cell recovery after the clinical manifestation of IDDM in children.

Mathematical formulae for the prediction of the residual beta cell function during the first two years of disease in children and adolescents with insulin-dependent diabetes mellitus

On the basis of a retrospective study of 71 children followed for 24 months after diagnosis of type I insulin dependent diabetes a fitted mathematical model was constructed for the prediction of the course of beta cell function from the time of diagnosis. Two equations were derived, one for the maximal basal (B-max) and the other for the maximal i.v. glucagon stimulated peak C-peptide (P-max) levels reached during the remission period. The prognostic variables selected for analysis were: peak C-peptide levels at diagnosis (Po), age sex, degree of obesity, pubertal rating, the presence of islet cell antibodies (ICA) and levels of GHb. Multivariate analysis of the data showed that Po (p = 0.0006), puberty (p = 0.041). obesity (p = 0.0021), sex (p = 0.031), ICA (p = 0.0045) and GHb(p = 0.0066) significantly contributed to the prediction formula obtained for B-max whereas the contribution of the above variables for P-max were: Po (p = 0.0019), puberty (p = 0.0187), obesity (p = 0.0058), sex (p = 0.0598), ICA (p = 0.0187) and GHb (p = 0.0027). The residuals of the observed values from the values fitted by the predicted equations served to define two separate groups demonstrating distinct differences in the natural course of beta cell function in type I diabetes. This fitted model may thus be useful in distinguishing between newly diagnosed young patients who will undergo remission, requiring lower insulin doses, and those who have little chance for remission. It might also be helpful in the selection of patients most likely to benefit from immunosuppression or modulation, to maximize the benefit to risk ratio for such patients.

Serum insulin profiles in consecutive children 2 years after the diagnosis of IDDM

We studied associations of 24-h serum insulin profiles with insulin dose, age, gender, haemoglobin A1c (HbA1c) and C-peptide values, as well as blood glucose profiles in 77 consecutive children-nine aged 2-4, 14 aged 5-8, 26 aged 9-12, and 28 aged 13-17 years--2 years after the onset of insulin-dependent diabetes mellitus (IDDM). Mean weight-based insulin doses in the four age groups were similar (0.7 +/- 0.2 U.kg-1.day-1 in all); body surface-area-based doses differed. Insulin doses correlated significantly with the 24-h mean and area-under-the-curve (AUC) values, and with mean values at 03.00 hours of serum insulin in the children aged 5-8 and 13-17 years. The mean insulin concentrations of the age groups (95% confidence intervals) increased with age [6.1 (3.8, 9.7), 7.6 (5.9, 9.8), 10.4 (8.6, 12.4), and 14.0 (11.6, 16.8) mU/l; p < 0.0002]. The 24-h mean of serum insulin together with HbA1c concentration predicted 32% of the variation of mean blood glucose concentrations. Of children aged less than 9 years, 50% had insulin values less than 5 mU/l (healthy subjects' lower reference limit), and 14% were of less than 2 mU/l (detection limit of the assay) at 03.00 hours. At 07.00 hours, 82% had insulin values of less than 5 mU/l, and 36% were of less than 2 mU/l, respectively. Some young children had night-time hypoglycaemia with simultaneous hypoinsulinaemia. Insulin profiles correlated poorly with the HbA1c and peak C-peptide values.(ABSTRACT TRUNCATED AT 250 WORDS)

Evidence for different clinical subtypes of type 1 diabetes mellitus: a prospective study

The purpose of this study was to determine whether the sex, age, severity of clinical presentation, presence of ICAs, IAs, and HLA-DR and DQ types could predict, in a cohort of newly-diagnosed diabetic children: (1) the duration of beta-cell function as measured by C-peptide response to a Sustacal meal; and (2) determine if those predictors could identify disease subtypes. A cohort of 170 consecutive patients was followed for 60 months after diagnosis. We found that age (0.0029), sex (0.0136), ICA (0.0001), presence of DKA (0.0070) and C-peptide peak at diagnosis (0.0000) significantly predicted the duration of residual beta-cell function over time. Furthermore, C-peptide secretion at diagnosis, presence of ICA, age and sex allowed the identification of three different prognostic groups with varying acceleration of beta-cell loss.

Glucose profiles in children two years after the onset of type 1 diabetes

The relationship of 24-h glucose profiles to age, haemoglobin A1c (HbA1c), and C-peptide concentration was analysed in consecutive, unselected children who had developed Type 1 diabetes 2 years earlier. Seventy-seven children in four age groups (age 2-4 years, n = 9; 5-8 years, n = 14; 9-12 years, n = 26; and 13-17 years, n = 28) were studied. Each child was hospitalized for 2 days for the investigations. Mean blood glucose concentration was 9.7 +/- 4.1 (SD) mmol l-1 in children aged 2-4 years; 10.7 +/- 4.0 mmol l-1 in those aged 5-8 years; 11.3 +/- 3.4 mmol l-1 in those aged 9-12 years; and 9.8 +/- 3.3 mmol l-1 in those aged 13-17 years. Results were > 7.0 mmol l-1 in 69% (range 56-76%) and > 10 mmol l-1 in 49% (39-57%) of the measurements. Values decreased by 30% (21-43%) between 10 pm and 3 am. The nadir of the mean profiles of the groups was always at 3 am. Glucose concentration was mmol l-1 in 25% (14-50%), < 2.5 mmol l-1 in 9.6% (0-21%), and < 2.0 mmol l-1 in 2.7% (0-4.2%) of the children at 3 am; hypoglycaemia was most common in those aged 5-8 years. Of the four profile characteristics used, mean blood glucose predicted HbA1c (R2 = 24.7%, p < 0.00005, multiple linear regression analysis), and slightly more in combination with age (R2 = 32.0%, p < 0.00005).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of a short prednisone regime at clinical onset of type 1 diabetes

The effect of corticosteroids on beta cell function and humoral immune response in type 1 diabetes was tested in a 2-month trial conducted on 32 newly diagnosed patients (age 22.8 +/- 1.4 years, mean +/- S.E.M.). Prednisone was administered at immunosuppressive dosage (1 mg.kg-1.day-1) during the initial 10 days and at a maintenance dosage (0.3 mg.kg-1.day-1) for 50 days. Patients (n = 32) were enrolled within 6 weeks after diagnosis and matched in pairs for age, sex, presence of islet cell antibodies (ICA) and glucagon stimulated C-peptide levels. Insulin discontinuation was not contemplated. All the patients who received prednisone became ICA during treatment but in some (4 out of 10) this effect was only transient. Insulin antibodies (IA) were significantly lower in the prednisone group at second and third month (P < 0.05). No patient experienced complete remission but in 10 prednisone and 4 control patients the insulin requirements were below 0.3 IU/kg (P < 0.05). With similar glycemia the fasting C-peptide levels were higher in the treated patients. The profile of the insulin requirements during the follow-up was different in the two groups and at 9 months the prednisone group needed less insulin than the control (P < 0.05). Interestingly, within the prednisone-treated group and after 6 months, the levels of stimulated C-peptide improved significantly among the ICA+ patients while they were steady or declined in ICA- (P < 0.01). The analysis of variance covariance confirmed a positive interaction between ICA and the administration of prednisone on the outcome of beta cell function.(ABSTRACT TRUNCATED AT 250 WORDS)

Correlation between residual beta-cell function and age at onset of spontaneous diabetes in Long Evans Tokushima lean rats

We studied the natural course of disease in spontaneously diabetic rats, Long Evans Tokushima Lean (LETL) rats, to determine whether it showed similar pathogenetic heterogeneity to that of patients with insulin-dependent diabetes mellitus (IDDM) with regard to the relationships between age at onset, rapidity of disease progress, and degree of beta-cell function at the time of its manifestation. Type 1 diabetes developed in 35 rats (6.3%) between 40 and 140 days of age. Eight rats that became diabetic at age 69 days or less were more severely ketotic at the time of first detection of glycosuria and showed more rapid deterioration than seven rats that became diabetic later after birth (mean plasma 3-hydroxybutyrate levels, 4,707 +/- 1,215 pmol/L v 1,390 +/- 859 pmol/L; mean +/- SEM, P < .01). The mean plasma levels and pancreatic content of immunoreactive insulin (IRI) of the early onset rats, 47 +/- 13 pmol/L and 19 +/- 12 pmol/g tissue weight, were significantly lower (P < .01) than the corresponding values of the late-onset rats, 262 +/- 52 pmol/L and 348 +/- 87 pmol/g tissue weight, respectively. Both values were markedly lower than the mean values of 25 nondiabetic LETL rats, 976 +/- 122 pmol/L and 3,488 +/- 628 pmol/g tissue weight. Plasma immunoreactive glucagon (IRG) levels were significantly increased in the diabetic groups (early onset, 57 +/- 13 pmol/L; late-onset, 51 +/- 12 pmol/L; nondiabetic, 18 +/- 1 pmol/L; P < .01). These changes in pancreatic hormone levels of the early onset and late-onset rats were compatible with the histological features of their pancreatic islets.(ABSTRACT TRUNCATED AT 250 WORDS)