Clinical heterogeneity of type 1 diabetes (T1D) found in Asia

Abnormal late postprandial glucagon response in type 1 diabetes is a function of differences in stimulated C-peptide concentrations

Background

The functional changes in alpha cells in patients with type 1 diabetes (T1D) with different residual beta cell functions remain poorly elucidated. The study aimed to investigate the relationship between glucagon secretion and C-peptide levels and to explore the relationship between glucagon response and glucose increment in respond to a secretagogue in a steamed bread meal tolerance test (BMTT) in T1D.

Methods

The study enrolled 43 adult patients with T1D and 24 healthy control subjects. Patients with T1D who underwent BMTT were divided into two groups based on peak C-peptide levels: C peptide low (CPL; C-peptide < 200 pmol/L; n=14) and high (CPH; C peptide ≥ 200 pmol/L; n=29). Plasma glucose, C-peptide, glucagon levels at 0, 30, 60, 120, and 180 min were measured. The glucagon response to the BMTT was defined by areas under the curve (AUC) as early (AUC0-30), late (AUC30-180), or total (AUC0-180) glucagon.

Results

Compared to healthy individuals, fasting plasma glucagon was lower and postprandial plasma glucagon level was increased in patients with T1D. Glucagon levels after BMTT between the CPL and CPH group showed significant group by time interaction. Peak glucagon and glucagon at 60-180 min, total and late glucagon response were higher in CPL than CPH group, while fasting glucagon and early glucagon response adjusted for glucose were comparable between CPL and CPH group. The higher late glucagon response and late glucagon response adjusted for glucose were associated with lower peak C-peptide in T1D. The higher late glucagon response and lower peak C-peptide were associated with the higher value of ▵glucose at 180 min.

Conclusion

Stimulated C-peptide levels affect the paradoxical increase in postprandial glucagon secretion in patients with T1D, especially late glucagon response. The exaggerated postprandial glucagon secretion further stimulates the elevation of postprandial glucose in patients with T1D.

Distinct changes to pancreatic volume rather than pancreatic autoantibody positivity: insights into immune checkpoint inhibitors induced diabetes mellitus

BACKGROUND

Immune checkpoint inhibitors (ICI) are promising treatment options for various cancers. However, their use is associated with immune-related adverse events (irAEs), including ICI-induced diabetes mellitus (ICI-DM). This study aimed to investigate the clinical features of ICI-DM, with a particular focus on alterations to pancreatic volume.

METHODS

We conducted a retrospective review of 2829 patients who received ICI treatment at the Chang Gung Memorial Hospital, Linkou, between January 2014 and December 2021. New-onset diabetes or diabetic ketoacidosis (DKA) was identified in ten patients receiving ICI therapy. Pancreatic volumes were assessed by manual segmentation of computed tomography (CT) images before and after ICI-DM diagnosis.

RESULTS

Among these ten patients, nivolumab was the most commonly used ICI (50.0%), followed by pembrolizumab (30.0%) and atezolizumab (20.0%). One patient received combination therapy with nivolumab and ipilimumab. The median age was 63.01 years (range: 40.1 - 87.8). ICI-DM developed after a median of 13.5 cycles (range: 2 - 42) of ICI treatment or 9.85 months (range:1.5 - 21.3) since ICI initiation. The initial presentation was DKA in 60.0% of patients. All patients had low or undetectable C-peptide levels (range: <0.033 - 0.133 nmol/L) and were negative for most type 1 diabetes mellitus (T1DM)-related autoantibodies; only one patient tested positive for glutamic acid decarboxylase antibodies. CT imaging revealed significant pancreatic atrophy, with a median pancreatic volume decrease of 19.92% (P = 0.038) from baseline and sustained significant decline at last follow-up (median - 37.14%, P = 0.012).

CONCLUSIONS

ICI-DM is often accompanied by pancreatic atrophy and approximately two-thirds of patients initially present with DKA. Although the majority of ICI-DM patients lack T1DM-related autoantibodies, identifying diminished pancreatic volumes through CT imaging provides valuable clues into the subclinical aspects of ICI-DM development, aiding in the prevention of diabetic emergencies.

TRIAL REGISTRATION

Not applicable.

Hypoglycemic Effect of an Herbal Decoction (Modified Gangsimtang) in a Patient with Severe Type 2 Diabetes Mellitus Refusing Oral Anti-Diabetic Medication: A Case Report

There is growing interest in alternative therapies for type 2 diabetes mellitus (T2DM) because some patients refuse to receive conventional therapies. In East Asia, herbal medicines are often used to treat T2DM, and modified Gangsimtang (mGST) is prescribed to treat a condition called wasting thirst (), which resembles T2DM. This study reported the treatment of hyperglycemia using herbal medicines without oral hypoglycemic agents or insulin therapy. Case presentation: A 36-year-old man with obesity was diagnosed with T2DM four years prior to hospitalization and experienced blood glucose level reduction from 22.2-27.8 mmol/L (400-500 mg/dL) to 5.6-11.1 mmol/L (100-200 mg/dL) by using herbal medicines. He visited D Korean Medicine Hospital with chronic polydipsia and general weakness as chief complaints. He was diagnosed with T2DM on the basis of a hemoglobin A1c level of 11.7% and 2 h postprandial blood glucose level of >25.0 mmol/L (450 mg/dL). Moreover, he was diagnosed with a "dual deficiency of qi and yin" () because of ordinary symptoms (). During his 30-day inpatient treatment, the patient received mGST 120 mL thrice daily; as a result, his postprandial blood glucose level decreased from 25.3 mmol/L (455 mg/dL) to 8.6 mmol/L (154 mg/dL), polydipsia decreased (visual analog scale score decreased from six to one), and triglyceride levels decreased from 11.7 mmol/L (1031 mg/dL) to 2.0 mmol/L (174 mg/dL). Plasma glucose levels remained stable for 6 months after the treatment, and no adverse events were observed over 200 days. We administered an herbal decoction to decrease plasma glucose levels without using oral hypoglycemic agents or insulin. Conclusions: Herbal decoctions such as mGST can reduce hyperglycemia in patients with T2DM who refuse conventional therapy.

Insulin Fact Sheet in Type 1 and 2 Diabetes Mellitus and Trends of Antidiabetic Medication Use in Insulin Users with Type 2 Diabetes Mellitus: 2002 to 2019

BACKGROUND

This study investigated the trends of insulin use among Korean patients with type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). Changes in prescription of antidiabetic medications in T2DM patients taking insulin therapy were evaluated.

METHODS

We analyzed data from the National Health Insurance Service database in Korea to evaluate the prevalence of insulin users and trends of insulin use in T1DM and T2DM patients from January 2002 to December 2019. We also investigated numbers and types of antidiabetic medications in insulin users with T2DM.

RESULTS

The overall total number of insulin users increased from 2002 to 2019, reaching 348,254 for T2DM and 20,287 for T1DM in 2019 compared with 109,974 for T2DM and 34,972 for T1DM in 2002. The proportion of patients using basal analogs and short acting analogs have increased and those using human insulin, premixed insulin, or biphasic human insulin have decreased (rapid acting analogs: 71.85% and 24.12% in T1DM and T2DM, respectively, in 2019; basal analogs: 76.75% and 75.09% in T1DM and T2DM, respectively, in 2019). The use of other antidiabetic medication in addition to insulin increased for T2DM, especially in dual therapy, reaching up to 52.35% in 2019 compared with 16.72% in 2002.

CONCLUSION

The proportion of the patients using basal or rapid acting analogs increased among all insulin users in both T1DM and T2DM patients. Among patients with T2DM, the proportion of patients using antidiabetic medications in addition to insulin was significantly increased compared to those who used insulin alone.

Prevalence and characteristics of misdiagnosed adult-onset type 1 diabetes mellitus in Thai people by random plasma C-peptide testing

Background

It is critical to determine the exact type of diabetes because misclassification led to inappropriate treatments. The classification of DM can be aided by the measurement of pancreatic autoantibodies and plasma C-peptide levels. Previous studies suggested that random plasma C-peptide testing in those with clinically diagnosed adult T1DM of at least 3 years duration has led to reclassification in some cases.

Aim

This study aimed to assess the prevalence and characteristics of misdiagnosed adult-onset type 1 diabetes mellitus in Thai people by random plasma C-peptide testing.

Methods

A cross-sectional study of adult Thai patients diagnosed with clinically diagnosed T1DM and DM duration of at least 3 years at Theptarin Hospital, a diabetes center in Bangkok, Thailand was studied. Clinically misdiagnosis of T1DM was defined by preserved endogenous insulin secretion. Characteristics of the misdiagnosed patients were compared with definite T1DM patients.

Results

A total of 73 patients (females 52.1%, mean age 42.2 ± 12.5 years, duration of DM 20.3 ± 11.3 years) were studied. The prevalence of available anti-GAD and anti-IA2 were 53.3% and 20.8%, respectively. Preserved endogenous insulin secretion evaluated by random C-peptide or stimulated C-peptide was found in 8 patients (11.0%). The misdiagnosed patients had higher prevalence of hypertension and diabetic complications. Three patients were suspected to have monogenic diabetes and five patients were reclassified as possible T2DM.

Conclusions

Approximately one-tenth of adult T1DM patients were misdiagnosed. Random plasma C-peptide testing at least 3 years after a diagnosis of T1DM was superior to the measurement of pancreatic autoantibodies. Our present study highlights the need to increase accuracy in the diagnosis of T1DM patients by re-assessing endogenous insulin production with measurement of random plasma C-peptide levels.

Comparison of Insulin-Treated Patients with Ambiguous Diabetes Type with Definite Type 1 and Type 2 Diabetes Mellitus Subjects: A Clinical Perspective

In clinical practice, the distinction between type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) can be challenging, leaving patients with "ambiguous" diabetes type. Insulin-treated patients (n=115) previously diagnosed with T2DM had to be re-classified based on clinical phenotype and laboratory results, and were operationally defined as having an ambiguous diabetes type. They were compared against patients with definite T1DM and T2DM regarding 12 clinical and laboratory features typically different between diabetes types. Characteristics of patients with ambiguous diabetes type, representing approximately 6% of all patients with T1DM or T2DM seen at our specialized clinic, fell in between those of patients with definite T1DM and T2DM, both regarding individual features and with respect to a novel classification based on multi-variable regression analysis (P<0.0001). In conclusion, a substantial proportion of diabetes patients in a tertiary care centre presented with an "ambiguous" diabetes type. Their clinical characteristics fall in between those of definite T1DM or T2DM patients.

The interferon regulatory factors, a double-edged sword, in the pathogenesis of type 1 diabetes

Type 1 diabetes (T1D) is an autoimmune disease resulted from the unrestrained inflammatory attack towards the insulin-producing islet β cells. Although the exact etiology underlying T1D remains elusive, viral infections, especially those specific strains of enterovirus, are acknowledged as a critical environmental cue involved in the early phase of disease initiation. Viral infections could either directly impede β cell function, or elicit pathological autoinflammatory reactions for β cell killing. Autoimmune responses are bolstered by a massive body of virus-derived exogenous pathogen-associated molecular patterns (PAMPs) and the presence of β cell-derived damage-associated molecular patterns (DAMPs). In particular, the nucleic acid components and the downstream nucleic acid sensing pathways serve as the major effector mechanism. The endogenous retroviral RNA, mitochondrial DNA (mtDNA) and genomic fragments generated by stressed or dying β cells induce host responses reminiscent of viral infection, a phenomenon termed as viral mimicry during the early stage of T1D development. Given that the interferon regulatory factors (IRFs) are considered as hub transcription factors to modulate immune responses relevant to viral infection, we thus sought to summarize the critical role of IRFs in T1D pathogenesis. We discuss with focus for the impact of IRFs on the sensitivity of β cells to cytokine stimulation, the vulnerability of β cells to viral infection/mimicry, and the intensity of immune response. Together, targeting certain IRF members, alone or together with other therapeutics, could be a promising strategy against T1D.

Recent information on test utilization and intraindividual change in anti-glutamic acid decarboxylase antibody in Korea: a retrospective study

INTRODUCTION

This study aimed to evaluate the test utilization and intraindividual changes of anti-glutamic acid decarboxylase antibody (GADA), a biomarker for autoimmune diabetes in Korean adults.

RESEARCH DESIGN AND METHODS

We retrospectively investigated longitudinally measured GADA test results to assess test utilization and intraindividual changes through a laboratory information system.

RESULTS

During the 3-year study period, 11 668 GADA tests were performed in 11 184 Korean adults. The overall rate of GADA positivity at initial measurement was 7.8%. Among the 11 668 test results, 871 GADA test results from 401 Korean patients (228 men and 173 women) requested by 54 hospitals were analyzed for intraindividual changes. Among these 401 patients, 80 (20.0%) had positive (≥2.0 U/mL) and 35 (8.7%) had gray zone GADA (1.0-1.9 U/mL) level at initial measurement. The prevalence of GADA-positive patients based on initial measurement was significantly different by type of medical institution. Among 80 patients with initial positive results, 5 (6.3%) experienced qualitative GADA changes during follow-up. Among the 321 patients with initially negative or gray zone GADA, 9 (2.8%) changed to GADA positive at least once during follow-up.

CONCLUSIONS

Although most patients had stable GADA results, some exhibited qualitative changes during follow-up. This study can help to understand the variation in GADA positivity in the monitored patients.

Prevalence and clinical characteristics of fulminant type 1 diabetes mellitus in Korean adults: A multi-institutional joint research

AIMS/INTRODUCTION

We aimed to determine the hospital-based prevalence and clinical features of fulminant type 1 diabetes mellitus in Korea.

MATERIALS AND METHODS

We identified all patients with diabetes who regularly visited the Endocrinology outpatient clinics at eight centers for a period >1 year between January 2012 and June 2017. We investigated their medical records retrospectively.

RESULTS

During this period, 76,309 patients with diabetes had been regularly followed up. Among them, 913 (1.2%) patients had type 1 diabetes mellitus . There were 462 patients with type 1 diabetes mellitus whose data at the time of the first diagnosis could be identified (359 and 103 with non-ketosis and ketosis onset, respectively). Of these, 15 (3.2% of type 1 diabetes mellitus, 14.6% of ketosis onset diabetes) patients had fulminant type 1 diabetes mellitus. The median ages at diagnosis were 40 and 27 years in the fulminant type 1 diabetes mellitus and non-fulminant type 1 diabetes mellitus groups, respectively. The patients with fulminant type 1 diabetes mellitus had higher body mass index, lower glycated hemoglobin and fasting/peak C-peptide, and lower frequent glutamic acid decarboxylase antibody-positive rate (P =0.0010) at diagnosis. Furthermore, they had lower glycated hemoglobin at the last follow-up examination than those with non-fulminant type 1 diabetes mellitus.

CONCLUSIONS

In this study, the prevalence of type 1 diabetes mellitus was 1.2% among all patients with diabetes, and that of fulminant type 1 diabetes mellitus was 3.2% among those newly diagnosed with type 1 diabetes mellitus. The glycated hemoglobin levels were lower in patients with fulminant type 1 diabetes mellitus than in those with non-fulminant type 1 diabetes mellitus at diagnosis and at the last follow-up examination.

Genome-wide association study reveals novel loci for adult type 1 diabetes in a 5-year nested case-control study

BACKGROUND

Type 1 diabetes (T1D) is a severe and prevalent metabolic disease. Due to its high heredity, an increasing number of genome-wide association studies have been performed, most of which were from hospital-based case-control studies with a relatively small sample size. The association of single nucleotide polymorphisms (SNPs) and T1D has been less studied and is less understood in natural cohorts.

AIM

To investigate the significant variants of T1D, which could be potential biomarkers for T1D prediction or even therapy.

METHODS

A genome-wide association study (GWAS) of adult T1D was performed in a nested case-control study (785 cases vs 804 controls) from a larger 5-year cohort study in Suzhou, China. Potential harmful or protective SNPs were evaluated for T1D. Subsequent expression and splicing quantitative trait loci (eQTL and sQTL) analyses were carried out to identify target genes modulated by these SNPs.

RESULTS

A harmful SNP for T1D, rs3117017 [odds ratio (OR) = 3.202, 95% confidence interval (CI): 2.296-4.466, P = 9.33 × 10^-4] and three protective SNPs rs55846421 (0.113, 0.081-0.156, 1.76 × 10^-9), rs75836320 (0.283, 0.205-0.392, 1.07 × 10^-4), rs362071 (0.568, 0.495-0.651, 1.66 × 10^-4) were identified. Twenty-two genes were further identified as potential candidates for T1D onset.

CONCLUSION

We identified a potential genetic basis of T1D, both protective and harmful, using a GWAS in a larger nested case-control study of a Chinese population.

Incidence of Type 1 Diabetes May Be Underestimated in the Chinese Population: Evidence From 21.7 Million People Between 2007 and 2017

OBJECTIVE

Previous reports of the annual incidence of type 1 diabetes (T1D) in China were conducted using retrospective hospital cases, which may not reflect the reality. This longitudinal study estimated T1D incidence in a Chinese population of 21.7 million from 2007 to 2017.

RESEARCH DESIGN AND METHODS

A population-based registry of T1D was performed by the Beijing Municipal Health Commission Information Center. Annual incidence and 95% CIs were calculated by age group and sex. The association of sex with T1D incidence and predicted new cases of T1D were assessed using Poisson regression models. Annual percentage change and average annual percentage of change were assessed using Joinpoint regression.

RESULTS

Overall, there were 6,875 individuals who developed T1D from 2007 to 2017 in this population. T1D incidence (/100,000 persons) (95% CI) significantly increased from 2.72 (2.51, 2.93) in 2007 to 3.60 (3.38, 3.78) in 2017 (P < 0.001). The T1D onset peak was in the 10-14-year-old age group. While no significant trend was found in the 0-14- and 15-29-year-old age groups, T1D incidence markedly increased from 1.87 to 3.52 in the ≥30-year-old age group (P < 0.05). The prevalence of diabetic ketoacidosis at diagnosis was highest in the 0-4-year-old age group. We predicted new cases of T1D will increase 1.57-fold over the next decade.

CONCLUSIONS

T1D incidence in this large Chinese population is higher than has been reported previously. From 2007 to 2017, although the incidence peak was in the 10-14-year age group, the T1D incidence increased sharply in adults but not in youth.

Selenium Deficiency Due to Diet, Pregnancy, Severe Illness, or COVID-19-A Preventable Trigger for Autoimmune Disease

The trace element selenium (Se) is an essential part of the human diet; moreover, increased health risks have been observed with Se deficiency. A sufficiently high Se status is a prerequisite for adequate immune response, and preventable endemic diseases are known from areas with Se deficiency. Biomarkers of Se status decline strongly in pregnancy, severe illness, or COVID-19, reaching critically low concentrations. Notably, these conditions are associated with an increased risk for autoimmune disease (AID). Positive effects on the immune system are observed with Se supplementation in pregnancy, autoimmune thyroid disease, and recovery from severe illness. However, some studies reported null results; the database is small, and randomized trials are sparse. The current need for research on the link between AID and Se deficiency is particularly obvious for rheumatoid arthritis and type 1 diabetes mellitus. Despite these gaps in knowledge, it seems timely to realize that severe Se deficiency may trigger AID in susceptible subjects. Improved dietary choices or supplemental Se are efficient ways to avoid severe Se deficiency, thereby decreasing AID risk and improving disease course. A personalized approach is needed in clinics and during therapy, while population-wide measures should be considered for areas with habitual low Se intake. Finland has been adding Se to its food chain for more than 35 years-a wise and commendable decision, according to today's knowledge. It is unfortunate that the health risks of Se deficiency are often neglected, while possible side effects of Se supplementation are exaggerated, leading to disregard for this safe and promising preventive and adjuvant treatment options. This is especially true in the follow-up situations of pregnancy, severe illness, or COVID-19, where massive Se deficiencies have developed and are associated with AID risk, long-lasting health impairments, and slow recovery.

Autoantibody-Negative Type 1 Diabetes: A Neglected Subtype

Up to 15% of individuals with a clinical phenotype of type 1 diabetes (T1D) do not have evidence of seropositivity for pancreatic islet autoantibodies. On this basis, they are classified as nonimmune or idiopathic, and remain an understudied population, as they are excluded from T1D immunomodulatory trials. Our limited understanding of the disease aetiopathogenesis in autoantibody-negative T1D hinders our ability to improve diagnostic pathways and discover novel therapeutic agents; particularly as we progress towards an era of precision medicine. This review summarises the current understanding and challenges in studying autoantibody-negative T1D. We review the literature regarding T1D classification, and the role of autoimmunity and defects in the immunogenic pathway that may distinguish autoantibody-positive and -negative T1D.

Type 1 diabetes mellitus in children: experience in Indonesia

The prevalence of type 1 diabetes mellitus (T1DM) in children in Indonesia is increasing although the real number is unknown due to high rate of misdiagnosis. Public and healthcare awareness on T1DM in children is still low, reflected by the high number of children diagnosed with diabetic ketoacidosis (DKA). The Indonesian Pediatric Society (IPS) had published a guideline on T1DM management, which consists of insulin injection, daily monitoring of blood glucose, nutrition, physical activity, and education. Aside from low awareness, current challenges on T1DM management in Indonesia are funding by the national health insurance, fasting during Ramadan, and inequities on DM care. The involvement of society, healthcare workers, stakeholders, and the government is of importance to ensure optimal management for children with diabetes.

Association between secondhand smoke exposure and diabetes mellitus in 131 724 Korean never smokers using self-reported questionnaires and cotinine levels: Gender differences

OBJECTIVE

The aim of this study is to compare the gender-different associations between secondhand smoke (SHS) exposure and diabetes in self-reported never smokers verified by cotinine.

METHODS

Self-reported never smokers verified by cotinine levels (<50 ng/mL) enrolled in the Kangbuk Samsung Health Study between April 2011 and December 2016 were included for this study. SHS exposure was defined as current exposure to passive smoke indoors at home or workplace. The gender-specific association between SHS exposure and diabetes was assessed using multivariable regression analyses.

RESULTS

Of the total 131 724 individuals (mean age 35 years, SD 7.1 years), 66.8% were female, and the prevalence of SHS exposure in the entire population was 22.9%. The prevalence of diabetes in the group exposed to SHS was higher than that in the group unexposed to SHS only in females (1.8% vs 1.2%, P < .001 for females; 2.2% vs 2.2%, P = .956 for males). A significant gender interaction existed for the relationships between SHS exposure and diabetes (P for interaction <.001). The multivariate regression model showed that SHS exposure was significantly associated with diabetes only in females (odds ratio [95% CI], 1.40 [1.20, 1.65] for females; 1.00 [0.85, 1.19] for males). In particular, females with SHS exposure ≥1 hour/day, ≥3 times/week, and ≥10 years showed an increased risk of diabetes by more than 50% compared to those without SHS exposure.

CONCLUSIONS

SHS exposure was significantly associated with diabetes in female never smokers with dose-dependent relationship. However, further longitudinal studies are needed to elucidate the gender difference in the incidence of diabetes associated with SHS exposure.

A pilot study of preproinsulin peptides reactivity in Chinese patients with type 1 diabetes

BACKGROUND

The aim of our study is to investigate whether preproinsulin (PPI) could trigger a proinflammatory CD4⁺ T cell response in Chinese patients with type 1 diabetes (T1D).

METHODS

Peripheral blood mononuclear cells were stimulated by a pool of 13 PPI peptides. Additional five PPI peptides previously proved to be antigenic in other cohorts of patients with T1D were also used. PPI reactive T cell responses were measured by interferon (IFN)-γ ELISPOT assay.

RESULTS

Fifty-one Chinese patients with T1D were enrolled in this study and 72.34% of them were positive for at least one islet autoantibody. The stimulation index (SI) value of IFN-γ response to PPI peptide pool or peptides with dominant epitopes was below 3 in patients when SI≥3 was used as the positive cut-off value. Two peptides (B9-23 and C19-A3) restricted to DQ8 or DR4 molecule failed to induce positive IFN-γ response in patients with high-risk HLA-DQ8 or HLA-DR4/DR9 alleles. RNA-seq analysis of PPI specific CD4⁺ T cell lines further showed that most of the IFN-γ associated genes remained unchanged.

CONCLUSIONS

This is the first report of CD4⁺ T cell epitope mapping of PPI in Chinese T1D. The lack of positive IFN-γ response to PPI peptides indicates that PPI might not be the principal antigenic candidate for autoreactive CD4⁺ T cells in Chinese T1D. Therefore, the efficacy of PPI-based immunotherapies in attenuating proinflammatory CD4⁺ T cell response requires further investigation.

Risk of early mortality and cardiovascular disease in type 1 diabetes: a comparison with type 2 diabetes, a nationwide study

Background

Both type 1 and type 2 diabetes are well-established risk factors for cardiovascular disease and early mortality. However, few studies have directly compared the hazards of cardiovascular outcomes and premature death among people with type 1 diabetes to those among people with type 2 diabetes and subjects without diabetes. Furthermore, information about the hazard of cardiovascular disease and early mortality among Asians with type 1 diabetes is sparse, although the clinical and epidemiological characteristics of Asians with type 1 diabetes are unlike those of Europeans. We estimated the hazard of myocardial infarction (MI), hospitalization for heart failure (HF), atrial fibrillation (AF), and mortality during follow-up in Korean adults with type 1 diabetes compared with those without diabetes and those with type 2 diabetes.

Methods

We used Korean National Health Insurance Service datasets of preventive health check-ups from 2009 to 2016 in this retrospective longitudinal study. The hazard ratios of MI, HF, AF, and mortality during follow-up were analyzed using the Cox regression analyses according to the presence and type of diabetes in ≥ 20-year-old individuals without baseline cardiovascular disease (N = 20,423,051). The presence and type of diabetes was determined based on the presence of type 1 or type 2 diabetes at baseline.

Results

During more than 93,300,000 person-years of follow-up, there were 116,649 MIs, 135,532 AF cases, 125,997 hospitalizations for HF, and 344,516 deaths. The fully-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident MI, hospitalized HF, AF, and all-cause death within the mean follow-up of 4.6 years were higher in the type 1 diabetes group than the type 2 diabetes [HR (95% CI) 1.679 (1.490–1.893) for MI; 2.105 (1.901–2.330) for HF; 1.608 (1.411–1.833) for AF; 1.884 (1.762–2.013) for death] and non-diabetes groups [HR (95% CI) 2.411 (2.138–2.718) for MI; 3.024 (2.730–3.350) for HF; 1.748 (1.534–1.993) for AF; 2.874 (2.689–3.073) for death].

Conclusions

In Korea, the presence of diabetes was associated with a higher hazard of cardiovascular disease and all-cause death. Specifically, people with type 1 diabetes had a higher hazard of cardiovascular disease and all-cause mortality compared to people with type 2 diabetes.

Identification of Novel T1D Risk Loci and Their Association With Age and Islet Function at Diagnosis in Autoantibody-Positive T1D Individuals: Based on a Two-Stage Genome-Wide Association Study

OBJECTIVE

Type 1 diabetes (T1D) is a highly heritable disease with much lower incidence but more adult-onset cases in the Chinese population. Although genome-wide association studies (GWAS) have identified >60 T1D loci in Caucasians, less is known in Asians.

RESEARCH DESIGN AND METHODS

We performed the first two-stage GWAS of T1D using 2,596 autoantibody-positive T1D case subjects and 5,082 control subjects in a Chinese Han population and evaluated the associations between the identified T1D risk loci and age and fasting C-peptide levels at T1D diagnosis.

RESULTS

We observed a high genetic correlation between children/adolescents and adult T1D case subjects (r _g = 0.87), as well as subgroups of autoantibody status (r _g ≥ 0.90). We identified four T1D risk loci reaching genome-wide significance in the Chinese Han population, including two novel loci, rs4320356 near BTN3A1 (odds ratio [OR] 1.26, P = 2.70 × 10^-8) and rs3802604 in GATA3 (OR 1.24, P = 2.06 × 10^-8), and two previously reported loci, rs1770 in MHC (OR 4.28, P = 2.25 × 10^-232) and rs705699 in SUOX (OR 1.46, P = 7.48 × 10^-20). Further fine mapping in the MHC region revealed five independent variants, including another novel locus, HLA-C position 275 (omnibus P = 9.78 × 10^-12), specific to the Chinese population. Based on the identified eight variants, we achieved an area under the curve value of 0.86 (95% CI 0.85-0.88). By building a genetic risk score (GRS) with these variants, we observed that the higher GRS were associated with an earlier age of T1D diagnosis (P = 9.08 × 10^-11) and lower fasting C-peptide levels (P = 7.19 × 10^-3) in individuals newly diagnosed with T1D.

CONCLUSIONS

Our results extend current knowledge on genetic contributions to T1D risk. Further investigations in different populations are needed for genetic heterogeneity and subsequent precision medicine.

A Case of Fulminant Type 1 Diabetes with Gastric and Urinary Retention

Fulminant type 1 diabetes (fT1D) is a severe subtype of type 1 diabetes which progresses rapidly with islet cells destroyed almost completely within a short period of time. It is often characterized by flu-like or gastrointestinal symptoms at the onset with negative islet-associated autoantibodies, resulting in an absolute deficiency of endogenous insulin secretion. Poor prognosis can be caused by the significantly higher incidence of metabolic disorders (such as severe ion disorders and elevated serum pancreatic enzymes), acute and chronic complications if not diagnosed and treated in a timely manner. We herein describe an fT1D patient with gastric and urinary retention along with severe ion disturbance, whose laboratory tests revealed diabetic ketoacidosis, peripheral neuropathy, retinopathy, nephropathy, and hypoproteinemia.

High Proportion of Adult Cases and Prevalence of Metabolic Syndrome in Type 1 Diabetes Mellitus Population in Korea: A Nationwide Study

BACKGROUND

The prevalence and incidence of type 1 diabetes mellitus (T1DM) in all age groups and the prevalence of metabolic syndrome in patients with T1DM in Korea were estimated.

METHODS

The incidence and prevalence of T1DM between 2007 and 2013 were calculated using the Korean National Health Insurance Service (NHIS) datasets of claims. Clinical characteristics and prevalence of metabolic syndrome in individuals with T1DM between 2009 and 2013 were determined using the database of NHIS preventive health checkups.

RESULTS

The prevalence of T1DM in Korea between 2007 and 2013 was 0.041% to 0.047%. The annual incidence rate of T1DM in Korea in 2007 to 2013 was 2.73 to 5.02/100,000 people. Although the incidence rate of typical T1DM was highest in teenagers, it remained steady in adults over 30 years of age. In contrast, the incidence rate of atypical T1DM in 2013 was higher in people aged 40 years or older than in younger age groups. Age- and sex-adjusted prevalence of metabolic syndrome in patients with T1DM was 51.65% to 55.06% between 2009 and 2013.

CONCLUSION

T1DM may be more common in Korean adults than previously believed. Metabolic syndrome may be a frequent finding in individuals with T1DM in Korea.

Slowly Progressive Type 1 Diabetes Mellitus: Current Knowledge And Future Perspectives

Slowly progressive type 1 insulin-dependent diabetes mellitus (SPIDDM), sometimes referred to as latent autoimmune diabetes in adults (LADA), is a heterogeneous disease that is often confused with type 1 and type 2 diabetes. As a result, there were few diagnostic criteria for this disorder until 2012, when the Japan Diabetes Society established criteria that could be used in clinical practice. A primary question is whether pathologic markers for type 1 or type 2 diabetes are present in the pancreas of patients with SPIDDM, because the phenotype of SPIDDM is similar to both type 1 and type 2 diabetes. Recent studies clarified pathologic findings in the pancreas of patients with SPIDDM, which included T-cell-mediated insulitis, a marker of type 1 diabetes; pseudoatrophic islets (islets specifically devoid of beta cells), another hallmark of type 1 diabetes; and a lack of amylin (ie, islet amyloid polypeptide) deposition to the islet cells, a pathologic marker of type 2 diabetes. In terms of preventing the loss of beta-cell function in patients with SPIDDM, several studies have shown that some drugs, including dipeptidyl peptidase-4 inhibitors, are effective. There is an increased need for early diagnosis of SPIDDM to preserve beta-cell function. This review presents updated findings on the pathogenesis and immunologic findings of the affected pancreas, diagnostic markers, risk factors for progression of beta-cell dysfunction, epidemiology, clinical features, diagnostic strategies, prevention strategies, and clinical options for patients with SPIDDM.

Distinct neutrophil counts and functions in newly diagnosed type 1 diabetes, latent autoimmune diabetes in adults, and type 2 diabetes

BACKGROUND

Recent discoveries from animal models demonstrated that neutrophils can induce type 1 diabetes (T1D) through infiltrating into the islets. However, the evidence of their actions in T1D patients is relatively rare, and the change trend of neutrophil numbers and functions in different subtypes of diabetes has not been investigated.

METHODS

Patients with newly diagnosed T1D (n = 189), latent autoimmune diabetes in adults (LADA) (n = 86), T2D (n = 235), and healthy controls (n = 709) were enrolled. Circulating neutrophil counts were measured, and their correlations with clinical parameters were analysed. Neutrophils were isolated by density gradient centrifugation and magnetic bead cell sorting method. Neutrophil migration rate and chemokine levels in the blood were explored by trans-well and ELISA, respectively. Neutrophil phagocytosis rate, adhesion molecules and chemokine receptors expression were investigated by flow cytometry.

RESULTS

Compared with controls, neutrophil counts decreased in T1D patients but increased in T2D patients, with no change in LADA patients. The numbers showed a gradual increase trend from T1D, LADA to T2D. In autoimmune diabetes, neutrophil counts were associated with the number and titre of positive autoantibodies against β-cell antigens. No difference was found in neutrophil phagocytosis rate, but neutrophil migration in T1D patients was impaired and associated with CD62L expression, which was related closely to the titre of autoantibody.

CONCLUSIONS

Neutrophil numbers and migration abilities displayed distinct levels in different types of diabetes. In T1D, CD62L seems to play an important role in the migration of neutrophils and β-cell autoimmunity.

Glutamic Acid Decarboxylase Autoantibody-negative Slowly Progressive Type 1 Diabetes Mellitus: A Case Report and Literature Review

A 59-year-old non-obese Japanese woman developed diabetes mellitus with a negative glutamic acid decarboxylase autoantibody (GADA) test result. Her hyperglycemia was initially well controlled by oral hypoglycemic agents; however, despite continued treatment the hyperglycemia gradually worsened. As she had endogenous insulin deficiency and tested positive for insulin autoantibody (IAA), insulin therapy was initiated. Few studies have investigated GADA-negative patients with slowly progressive type 1 diabetes mellitus (SPT1D). Our IAA-positive SPT1D patient progressed from the clinical onset of diabetes mellitus to starting insulin therapy relatively quickly (1.5 years), similarly to other previously reported non-obese patients with GADA-positive SPT1D.

Latent Autoimmune Diabetes in Adults: A Review on Clinical Implications and Management

Latent autoimmune diabetes in adults (LADA) is a heterogeneous disease characterized by a less intensive autoimmune process and a broad clinical phenotype compared to classical type 1 diabetes mellitus (T1DM), sharing features with both type 2 diabetes mellitus (T2DM) and T1DM. Since patients affected by LADA are initially insulin independent and recognizable only by testing for islet-cell autoantibodies, it could be difficult to identify LADA in clinical setting and a high misdiagnosis rate still remains among patients with T2DM. Ideally, islet-cell autoantibodies screening should be performed in subjects with newly diagnosed T2DM, ensuring a closer monitoring of those resulted positive and avoiding treatment of hyperglycaemia which might increase the rate of β-cells loss. Thus, since the autoimmune process in LADA seems to be slower than in classical T1DM, there is a wider window for new therapeutic interventions that may slow down β-cell failure. This review summarizes the current understanding of LADA, by evaluating data from most recent studies, the actual gaps in diagnosis and management. Finally, we critically highlight and discuss novel findings and future perspectives on the therapeutic approach in LADA.

Incidence of type 1 diabetes in China, 2010-13: population based study

OBJECTIVE

To estimate the incidence of type 1 diabetes in all age groups in China during 2010-13.

DESIGN

Population based, registry study using data from multiple independent sources.

SETTING

National registration system in all 505 hospitals providing diabetes care, and communities of patients with diabetes in 13 areas across China, covering more than 133 million person years at risk, approximately 10% of the whole population.

PARTICIPANTS

5018 people of all ages with newly diagnosed type 1 diabetes and resident in the study areas from 1 January 2010 to 31 December 2013.

MAIN OUTCOME MEASURES

Incidence of type 1 diabetes per 100 000 person years by age, sex, and study area. Type 1 diabetes was doctor diagnosed and further validated by onsite follow-up. Completeness of case ascertainment was assessed using the capture mark recapture method.

RESULTS

5018 cases of newly diagnosed type 1 diabetes were ascertained: 1239 participants were aged <15 years, 1799 were aged 15-29 years, and 1980 were aged ≥30 years. The proportion of new onset cases in participants aged ≥20 years was 65.3%. The estimated incidence of type 1 diabetes per 100 000 persons years for all ages in China was 1.01 (95% confidence interval 0.18 to 1.84). Incidence per 100 000 persons years by age group was 1.93 (0.83 to 3.03) for 0-14 years, 1.28 (0.45 to 2.11) for 15-29 years, and 0.69 (0.00 to 1.51) for ≥30 years, with a peak in age group 10-14 years. The incidence in under 15s was positively correlated with latitude (r=0.88, P<0.001), although this association was not observed in age groups 15-29 years or ≥30 years.

CONCLUSION

Most cases of new onset type 1 diabetes in China occurred among adults. The incidence of type 1 diabetes in Chinese children was among the lowest reported in the study.

Recent findings on fulminant type 1 diabetes

Fulminant type 1 diabetes (fT1D) is a new subtype of type 1 diabetes proposed by Imagawa in 2000. It is a clinical syndrome characterized by a markedly rapid and almost complete destruction of pancreatic β cells. Metabolic derangement is more severe in this subtype than in autoimmune type 1 diabetes. The incidence of fT1D is associated with HLA DRB1*04:05DQB1*04:01; both innate and acquired immune disorders might contribute to the development of fT1D. The presence of specific innate immune responses to enterovirus infection connected with enhanced adaptive immune pathways responsible for aggressive β cell toxicity in fT1D. The process of β cell destruction is extremely rapid in fT1D, and the insulin secretary capacity rarely recovers after the onset. The serum glycated albumin to glycated haemoglobin ratio is significantly higher in fT1D; a cut-off value of 3.2 for serum glycated albumin to glycated haemoglobin ratio yielded 97% sensitivity and 98% specificity for differentiating fT1D from type 2 diabetes. Fulminant type 1 diabetes is associated with pregnancy. This article also updates the diagnostic criteria for fT1D by the Japanese Diabetes Association in 2012.