Idiopathic type 1 diabetes in Dallas, Texas: a 5-year experience

The clinical value of glycosylated hemoglobin level in newly diagnosed ketosis-prone type 2 diabetes

Objective

To evaluate the clinical value of glycosylated hemoglobin (HbA1c) in newly diagnosed ketosis-prone type 2 diabetes (KPD).

Methods

A total of 330 patients with newly diagnosed type 2 diabetes (T2DM) hospitalized in our department with an average age of 48.72 ± 13.07 years old were selected and divided into T2DM group (193 cases) and KPD group (137 cases) according to whether they were combined with ketosis. According to the quartile level of HbA1c, they were divided into group A (HbA1c < 8.90%, 84 cases), group B (8.90%≤HbA1c < 10.70%, 86 cases), group C (10.70%≤HbA1c ≤ 12.40%, 85 cases) and group D (HbA1c > 12.40%, 75 cases). The general clinical features, laboratory indicators and islet function of each group were compared. Spearman correlation analysis was used to explore the correlation between HbA1c and β- Hydroxybutyric acid (β- HB) and islet function. ROC curve was used to analyze the sensitivity and specificity of HbA1c in diagnosing KPD, and the optimal tangent point was obtained.

Results

HbA1c, β-HB, FFA, RBG, insulin dosage, GSP, OGTT (0, 0.5, 1, 2, 3h) in KPD group were significantly higher than those in T2DM group (P< 0.001). HDL-C, IRT (0, 0.5, 1, 2, 3h), HOMA-β, HOMA-IR, HOMA-IS, ΔC30/ΔG30, AUC insulin were significantly lower than those in T2DM group (P< 0.001). With the increase of HbA1c level, the incidence of ketosis, β-HB, FFA and insulin dosage increased, while IRT (0, 0.5, 1, 2, 3h), ΔC30/ΔG30, AUC insulin, HOMA-β and HOMA-IS decreased accordingly (P< 0.001). In all newly diagnosed T2DM patients, Spearman correlation analysis showed that HbA1c was positively correlated with β-HB (r=0.539, P < 0.001), and was negatively correlated with HOMA-β (r=-0.564, P < 0.001), HOMA-IS (r=-0.517, P < 0.01, P < 0.001), HOMA-IR (r=-0.177, P < 0.001), ΔC30/ΔG30 (r=-0.427, P < 0.01) and AUC insulin (r=-0.581, P < 0.001). In ROC curve analysis, the optimal threshold for the diagnosis of KPD was 10.15%, Youden index was 0.616, area under the curve (AUC) was 0.882, sensitivity = 92.70%, specificity = 70.50%.

Conclusion

In newly diagnosed T2DM patients, if HbA1c > 10.15%, it is more likely to develop KPD. Monitoring HbA1c level is conducive to timely detection of high-risk individuals with KPD and taking appropriate measures to prevent the occurrence and development of the disease.

Support Provided by Caregivers for Community-Dwelling Diabetic Hispanic Adults with Intellectual Disabilities and Comorbid Conditions

Diabetes is an age-related chronic health condition and a major public health concern. Diabetes is one of the significant causes of morbidity and mortality and a major contributing factor to dementia. Recent research reveals that Hispanic Americans are at an increased risk of chronic conditions such as diabetes, dementia, and obesity. Recent research also revealed that diabetes develops at least ten years earlier in Hispanics and Latinos than in neighboring non-Hispanic whites. Furthermore, the management of diabetes and providing necessary/timely support is a challenging task for healthcare professionals. Caregiver support is an emerging area of research for people with diabetes, mainly family caregiver support work for Hispanic and Native Americans. Our article discusses several aspects of diabetes, factors associated with diabetes among Hispanics, its management, and how caregivers can support individuals with diabetes.

A Pediatric Case of Ketosis-Prone Type 2 Diabetes Requiring Insulin Therapy

In recent years, cases of diabetic ketoacidosis (DKA) or ketosis as the initial manifestation of diabetes with a similar clinical course to that of type 2 diabetes have been reported. This phenotype has been recognized as ketosis-prone type 2 diabetes (KPD). Most cases of KPD occur in adults, and the typical clinical course is that patients are often able to wean off insulin therapy after initial treatment. We report a pediatric case of ketosis-prone type 2 diabetes requiring insulin therapy with four years of follow-up. Our case suggests that patients with KPD may require strict management, including weight control, compared with patients with typical type 2 diabetes.

Two Fifth-Generation Fighter Pilots Discovered with Latent Autoimmune Diabetes

BACKGROUND: Fighter pilots undergo extensive medical screening but may still miss rare diseases like latent autoimmune diabetes in adults (LADA). LADA patients have circulating autoantibodies directed against pancreatic beta cell antigens and present with frank diabetes late in life which may elude conventional military flight screening.CASE REPORT: Two fifth-generation fighter pilots, a 38-yr-old man (patient 1) and a 27-yr-old man (patient 2), with no significant past medical histories developed symptoms of fatigue, weight loss, episodic polyuria, and arthralgia. Patient 1's symptoms were initially thought to have been caused by COVID-19, but he subsequently tested negative for viral infection. Lab work instead showed elevated TSH, HgbA1C 11.4%, positive GAD-65, anti-TPO, and anti-islet cell antibodies. Patient 2 developed symptoms following a military deployment and a 72-h diarrheal illness. Due to flight status, patient 2 did not seek expert medical attention for several months, but lab work found HgbA1C of 10.4%, positive GAD-66, and ZnT8 antibodies. Both patients were started on insulin therapy. Patient 1 was also started on levothyroxine for hypothyroidism and retired from flying duties. Patient 2 eventually transitioned to metformin without insulin and returned to flying duties with an aeromedical waiver.DISCUSSION: Our patients maintained peak physical fitness throughout their selection and aviation careers, which likely delayed their clinical presentation. Current USAF flight rules prohibit insulin use with flying fighter aircraft. Early antibody screening during pilot selection may be a cost-effective means of diagnosis as traditional screening techniques are unlikely to detect LADA.Zhang JX, Berry J, Kim NM, Gray JJ, Fotheringham S, Sauerwein TJ. Two fifth-generation fighter pilots discovered with latent autoimmune diabetes. Aerosp Med Hum Perform. 2022; 93(2):106-110.

Circulating osteocalcin: A potential predictor of ketosis in type 2 diabetes

AIMS

Osteocalcin contributes to the regulation of endocrine system. However, the association between osteocalcin and ketosis has not been evaluated. We thus aimed to explore the relationship between total osteocalcin and risk of ketosis in type 2 diabetes (T2DM).

MATERIALS AND METHODS

We identified 6157 diabetes patients from Shanghai Tenth People's Hospital between 1 January 2011 and 1 March 2017. Six hundred eight subjects were enrolled in the retrospective cross-sectional study: 304 T2DM patients with ketosis whose age, gender, and body mass index were matched with 304 T2DM patients without ketosis. A further retrospective nested case-control study was conducted in 252 T2DM patients without ketosis for a mean duration of 21.58 ± 12.43 months to investigate the occurrence of ketosis.

RESULTS

Osteocalcin levels were negatively correlated with blood ketones (adjusted r = -0.263) and urine ketones (adjusted r = -0.183). The inverse dose-dependent relationship of osteocalcin and risk of ketosis was present across osteocalcin level quintiles (top quintile as the reference, adjusted odds ratio [95% CI] = 2.56 [0.80-8.17], 3.71 [0.90-15.29], 10.77 [2.63-44.15], 23.81 [4.32-131.17] per osteocalcin quintile, respectively). Ketosis occurred in 17 of the 252 T2DM patients during follow-up. The Cox regression analysis indicated that osteocalcin was an independent protective factor against development of ketosis (adjusted hazard ratio [95% CI]: 0.668 [0.460-0.971]).

CONCLUSIONS

Total osteocalcin can be used as a predictor of ketosis in T2DM.

Risk Factors of Ketosis in Obese Ketosis-Prone Diabetic Patients: A Case-Control Study

INTRODUCTION

Different types of ketosis-prone obese diabetic patients are seen in the clinic. At present, the mechanism responsible for ketosis onset in these patients remains unclear, and we do not know how these patients should be optimally treated to prevent recurrent ketosis. Therefore, this study aims to investigate risk factors of ketosis in obese ketosis-prone diabetic (OB-KPD) patients.

METHODS

In an observational case-control study, primary OB-KPD patients [body mass index (BMI) ≥ 28 kg/m²] were selected as the study group (OB-KPD group), and primary obese type 2 diabetes patients served as the control group (OB-T2DM group). Clinical diagnostic assessments of fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), blood lipid, area under curve of serum C-peptide (AUC_C-P) after steamed bread meal, insulin sensitivity index (ISI), β-hydroxybutyric acid (β-HB) and free fatty acid (FFA) vlaues of the subjects were collected. Subjects in the OB-KPD group were followed up for 1 year to determine the likelihood of insulin therapy cessation and whether ketosis recurred by assessing clinical chemistry parameters at 1-year follow-up.

RESULTS

Seventy-five subjects were screened, of which 15 were not included in the study for several identified clinical reasons. On enrollment, the OB-KPD group displayed significantly higher FPG, HbA1c and FFA levels than the OB-T2DM group (p < 0.01), while AUC_C-P and ISI values were significantly lower than in the OB-T2DM group (p < 0.01 and p = 0.03). Statistical analysis showed that increases in β-HB in the OB-KPD group were associated with increased blood glucose and FFA and decreased AUC_C-P and ISI values. Furthermore, decreases in AUC_C-P were closely associated with increased blood glucose values.

CONCLUSION

The occurrence of ketosis in ketosis-prone obese diabetic patients may be related to glucose and lipid metabolism disorders, increased insulin resistance and decreased β-cell secretory functions.

TRIAL REGISTRATION

This work was registered at the Chinese Clinical Trial Registry with trial registration identifier no. ChiCTR1900025909.

Clinical guidelines for type 1 diabetes mellitus with an emphasis on older adults: an Executive Summary

We present a summary of a guideline produced by an international group of experts for managing type 1 diabetes in adults with an emphasis on the special needs of older people with this condition. The rationale for delivering high-quality diabetes care for adults with type 1 diabetes, why it is important to include older people in our considerations, and the key underpinning principles of the guideline are included. The structure of the recommendations given is described and consists of 'general' recommendations followed by 'specific' recommendations according to three categories depending on the characteristics of adults addressed, such as functional level or self-management ability. Recommendations are provided in the areas of: clinical diagnosis, establishing management plans and glucose regulation, diabetes self-management education, nutritional therapy, physical activity, exercise and lifestyle modification, insulin treatments and regimens, use of technology in diabetes management, hypoglycaemia, managing cardiovascular risk, management of microvascular risk, and inpatient management of type 1 diabetes and ketoacidosis.

Non-immune-mediated versus immune-mediated type 1 diabetes: diagnosis and long-term differences-retrospective analysis

BACKGROUND

The American Diabetes Association proposed two subcategories for type 1 diabetes mellitus: type 1A or immune-mediated diabetes (IDM) and type 1B or idiopathic diabetes. The absence of β-cell autoimmune markers, permanent insulinopenia and prone to ketoacidosis define the second category, whose pathogenesis remains unclear. Only a minority of patients fall into this category, also designated non-immune-mediated (NIDM), which is considered by several authors similar to type 2 diabetes. The aim of this study is to evaluate differences at the diagnosis and 10 years later of two categories.

METHODS

Retrospective cohort study of patients with β-cell autoimmune markers performed at diagnosis and undetectable c-peptide. Were excluded patients with suspicion of another specific type of diabetes. We obtained two groups: IDM (≥ 1 positive antibody) and NIDM (negative antibodies). Age, family history, anthropometry, duration of symptoms, clinical presentation, blood glucose at admission, A1C, lipid profile, arterial hypertension, total diary insulin dose (TDID), microvascular and macrovascular complications were evaluated. Results were considered statistically significant with p < 0.05.

RESULTS

37 patients, 29 with IDM and 8 patients with NIDM. The age of diagnosis of IDM group (23 years) was significantly different (p = 0.004) from the NIDM group (38.1). The body mass index (BMI) at the diagnosis did not differ significantly (p = 0.435). The duration of symptoms was longer in the NIDM (p = 0.003). The disease presentation (p = 0.744), blood glucose (p = 0.482) and HbA1c (p = 0.794) at admission and TDID at discharge (p = 0.301) did not differ significantly. Total and LDL cholesterol levels were higher in NIDM group but did not differ significantly (p = 0.585 and p = 0.579, respectively). After 10 years BMI did not differ between groups (p = 0.079). Patients with IDM showed a significantly higher HbA1c (p = 0.008) and TDID (p = 0.017). Relative to the lipid profile, there was no significant difference, however the LDL cholesterol and triglycerides were higher on the NIDM group, as the percentage of hypertension. Microvascular complications were higher in the IDM group, but no significant difference was found.

CONCLUSION

Patients with IDM had a poor metabolic control and higher insulin requirement. Patients with NIDM were older and showed higher cardiovascular risk, resembling a clinical phenotype of type 2 diabetes.

Prevalence and clinical characteristics of hypertension and metabolic syndrome in newly diagnosed patients with ketosis-onset diabetes: a cross-sectional study

BACKGROUND

To investigate the prevalence and clinical characteristics of hypertension (HTN) and metabolic syndrome (MetS) in newly diagnosed diabetes with ketosis-onset.

METHODS

A cross-sectional study was adopted in 734 newly diagnosed diabetics including 83 type 1 diabetics with positive islet-associated autoantibodies, 279 ketosis-onset diabetics without islet-associated autoantibodies and 372 non-ketotic type 2 diabetics. The clinical characteristics of HTN and MetS were compared across the three groups, and the risk factors of them were appraised in each group.

RESULTS

The prevalence of HTN and MetS were substantially higher in the ketosis-onset diabetics (34.4% for HTN and 58.8% for MetS) than in the type 1 diabetics (15.7% for HTN, P = 0.004; 25.3% for MetS, P < 0.001), but showed no remarkable difference compared with the type 2 diabetics (42.7% for HTN, P = 0.496; 72.3% for MetS, P = 0.079). Furthermore, the risk factors for both HTN and MetS in the ketosis-onset diabetics resembled those in the type 2 diabetics, but significantly different from those in the type 1 diabetics.

CONCLUSIONS

The prevalence of HTN and MetS in the ketosis-onset diabetics were magnificently higher than in the type 1 diabetics but showed no difference in comparison to the type 2 diabetics. Likewise, the clinical features and risk factors of HTN and MetS in the ketosis-onset diabetes resembled those in the type 2 diabetes but differed from those in the type 1 diabetes. Our findings indicate that ketosis-onset diabetes should be classified into type 2 diabetes rather than idiopathic type 1 diabetes.

Evaluation and management of ketosis-prone diabetes

INTRODUCTION

Patients presenting with diabetic ketoacidosis (DKA) who lack the classic phenotype of autoimmune type 1 diabetes have become increasingly identified in recent decades. This has led to the recognition of heterogeneous syndromes of 'ketosis-prone diabetes' (KPD). Evaluation and optimal management of KPD differs from that of 'typical' type 1 or type 2 diabetes. Awareness of these differences and a systematic approach to diagnosis and treatment can improve glycemic control and prevent both acute and chronic complications of diabetes.

AREAS COVERED

This article reviews the Aß classification scheme ('A' for autoantibody status and 'ß' for beta cell functional reserve) which accurately delineates subgroups of KPD, and addresses the relevance of defining these subgroups for clinical outcomes and long-term insulin dependence. Subsequently, the detailed evaluation and management of KPD patients after their index DKA episode is described.

EXPERT COMMENTARY

Among patients presenting with DKA, it is important to diagnose specific subgroups of KPD and not assume that they represent exclusively patients with autoimmune type 1 diabetes. The Aß classification is an accurate aid to diagnosis, and permits optimal management of the subgroups (e.g., insulin treatment for the ß- subgroups; follow-up testing and a range of treatment options for the ß+ subgroups).

Higher cardiometabolic risk in idiopathic versus autoimmune type 1 diabetes: a retrospective analysis

BACKGROUND

Idiopathic type 1 diabetes mellitus (IDM) is characterized by an onset with insulinopenia and ketoacidosis with negative β-cell autoimmunity markers and lack of association with HLA. The aim of the study is to compare the clinical and metabolic parameters, the macro and microvascular complications, the adipose tissue dysfunction and the insulin secretion and sensitivity indexes in patients with IDM and autoimmune type 1 diabetes mellitus (ADM) at clinical onset.

METHODS

Thirty patients with IDM and 30 with ADM, matched for age and gender, were retrospectively analyzed. BMI, waist circumference, lipids, glycemia, HbA1c, insulin requirement, glutamic oxaloacetic and glutamic pyruvic transaminases (GOT and GPT), glucagon stimulated c-peptide (GSC-pep) test levels, M value during hyperinsulinemic euglycemic clamp and Visceral Adiposity Index (VAI) were obtained from our database.

RESULTS

Patients with IDM showed a significantly higher BMI (p 0.012), WC (p 0.07), VAI (p 0.004), LDL-cholesterol (p 0.027), GOT (p 0.005), GPT (p 0.001), M value (p 0.006) and GSC-pep peak (p 0.036), with concomitant lower HDL-cholesterol (p < 0.001), than patients with ADM. In addition, patients with IDM showed a more marked familial history for diabetes (p 0.005) and a higher percentage of hepatic steatosis (p 0.001), visceral obesity (p 0.032) and hypercholesterolemia (p 0.007) compared to patients with ADM.

CONCLUSIONS

Patients with IDM show many metabolic complications at onset, such as visceral obesity, hepatic steatosis and hypercholesterolemia and a higher cardiometabolic risk, than patients with ADM, similarly to patients with type 2 diabetes at onset.

From Sea to Shining Sea and the Great Plains to Patagonia: A Review on Current Knowledge of Diabetes Mellitus in Hispanics/Latinos in the US and Latin America

The past two decades have witnessed many advances in the prevention, treatment, and control of diabetes mellitus (DM) and its complications. Increased screening has led to a greater recognition of type 2 diabetes mellitus (type 2 DM) and prediabetes; however, Hispanics/Latinos, the largest minority group in the US, have not fully benefited from these advances. The Hispanic/Latino population is highly diverse in ancestries, birth places, cultures, languages, and socioeconomic backgrounds, and it populates most of the Western Hemisphere. In the US, the prevalence of DM varies among Hispanic/Latino heritage groups, being higher among Mexicans, Puerto Ricans, and Dominicans, and lower among South Americans. The risk and prevalence of diabetes among Hispanics/Latinos are significantly higher than in non-Hispanic Whites, and nearly 40% of Hispanics/Latinos with diabetes have not been formally diagnosed. Despite these striking facts, the representation of Hispanics/Latinos in pharmacological and non-pharmacological clinical trials has been suboptimal, while the prevalence of diabetes in these populations continues to rise. This review will focus on the epidemiology, etiology and prevention of type 2 DM in populations of Latin American origin. We will set the stage by defining the terms Hispanic, Latino, and Latin American, explaining the challenges identifying Hispanics/Latinos in the scientific literature and databases, describing the epidemiology of diabetes-including type 2 DM and gestational diabetes mellitus (GDM)-and cardiovascular risk factors in Hispanics/Latinos in the US and Latin America, and discussing trends, and commonalities and differences across studies and populations, including methodology to ascertain diabetes. We will discuss studies on mechanisms of disease, and research on prevention of type 2 DM in Hispanics/Latinos, including women with GDM, youth and adults; and finalize with a discussion on lessons learned and opportunities to enhance research, and, consequently, clinical care oriented toward preventing type 2 DM in Hispanics/Latinos in the US and Latin America.

Clinical characteristics, beta-cell dysfunction and treatment outcomes in patients with A-β+ Ketosis-Prone Diabetes (KPD): The first identified cohort amongst Asian Indians

OBJECTIVE

Ketosis-prone diabetes (KPD), an atypical form of diabetes, has emerged as a heterogeneous syndrome in multiple ethnic groups. The objectives of this study were to look into the clinical characteristics of adult Asian Indian patients with recently diagnosed, antibody negative diabetes presenting with unprovoked ketoacidosis (A-β+ KPD) and to determine the natural course of recovery of beta-cell functions on serial follow-up over one year.

RESEARCH DESIGN AND METHODS

Newly diagnosed adult diabetes patients (n=11) with suspected KPD (A-β+) were prospectively studied over a period of 1-year with serial evaluations of clinical, biochemical and beta-cell secretion characteristics. These were compared with a control group (n=23) of KPD (A+β-) (classical Type 1A diabetes) with similar presentation. Beta-cell secretion was assessed by fasting and stimulated C-peptide values after a standard mixed meal challenge. Glycaemic control and treatment outcomes were also documented.

RESULTS

In comparison to the A+β- KPD controls, the A-β+ KPD patients had a significantly older age, higher BMI, stronger family history of type 2 diabetes, more severe ketoacidosis and higher fasting and stimulated C-peptide level at presentation. On serial follow-up, the patients with KPD achieved complete recovery of their beta-cell function with remission from insulin-dependence within 3-4months without further recurrences of DKA.

CONCLUSIONS

This is the first reported series of A-β+ KPD from India. The phenotype of Indian A-β+ KPD patients differs from their Western counterparts in that they are relatively younger and leaner, though the male preponderance and natural history of recovery of beta-cell dysfunction bears similarity.

DIABETIC KETOACIDOSIS: A COMMON DEBUT OF DIABETES AMONG AFRICAN AMERICANS WITH TYPE 2 DIABETES

OBJECTIVE

More than half of African Americans (AA) with a new diagnosis of diabetic ketoacidosis have clinical and metabolic features of type 2 diabetes during follow-up. This particular presentation of diabetes has been termed as ketosis-prone type 2 diabetes (KPDM) or atypical diabetes.

METHODS

We review the epidemiology, diagnosis, pathophysiology, and acute and long-term management of AA with KPDM and compare these similarities to patients with type 2 diabetes.

RESULTS

In contrast to the long-term insulin requirement of auto-immune type 1 diabetes, patients with KPDM are able to discontinue insulin after a few months of therapy and maintain acceptable glycemic control for many years on either diet or oral agents. Patients with KPDM have significant impairment of both insulin secretion and insulin action at presentation; however, at the time of near-normoglycemia remission, insulin secretion and action improve to levels similar to hyperglycemic patients with ketosis-resistant type 2 diabetes. In the long term, however, patients with KPDM have a decline in β-cell function similar to patients with type 2 diabetes. Recent studies indicate that treatment with metformin and dipeptidyl peptidase-4 inhibitors can prolong the period of near-normoglycemia remission for several years compared to placebo therapy.

CONCLUSION

KPDM is a unique but common presentation of newly diagnosed African Americans with type 2 diabetes.

ABBREVIATIONS

A(+/-) = auto-antibody positive/negative AA = African Americans DKA = diabetic ketoacidosis FFA = free fatty acids G6PD = glucose-6-phosphate dehydrogenase GAD-65 = 65-kDA glutamic acid decarboxylase HBA1c = glycated hemoglobin A1c HHV8 = human herpes virus 8 HLA = human leukocyte antigen KPDM = ketosis-prone type 2 diabetes.

HbA1c as a Screening tool for Ketosis in Patients with Type 2 Diabetes Mellitus

Ketosis in patients with type 2 diabetes mellitus (T2DM) is overlooked due to atypical symptoms. The objective of this study is to evaluate the value of hemoglobin A_1c (HbA_1c) as a screening tool for ketosis in T2DM patients. This retrospective study consisted of 253 T2DM patients with ketosis at Shanghai 10th People’s Hospital during a period from January 1, 2011 to June 30, 2015. A control group consisted of 221 T2DM patients without ketosis randomly selected from inpatients during the same period. Receiver operating characteristic curve (ROC) analysis was used to examine the sensitivity and specificity of HbA_1c as an indicator for ketosis. Higher HbA_1c levels were correlated with ketosis. In patients with newly diagnosed T2DM, the area under the curve (AUC) was 0.832, with 95% confidence interval (CI) 0.754–0.911. The optimal threshold was 10.1% (87 mmol/mol). In patients with previously diagnosed T2DM, the AUC was 0.811 (95% CI: 0.767–0.856), with an optimal threshold of 8.6% (70 mmol/mol). HbA_1c is a potential screening tool for ketosis in patients with T2DM. Ketosis is much more likely with HbA_1c values at ≥10.1% in patients with newly diagnosed T2DM and HbA_1c values at ≥8.6% in patients with previously diagnosed T2DM.

Early beta-cell dysfunction characterizes males with type 2 diabetes of Yemenite origin

AIMS

The aim of the current study was to characterize β-cell function, insulin sensitivity and line of inheritance in patients with recent-onset type 2 diabetes of Yemenite and non-Yemenite Jewish origin.

METHODS

A cohort study including 121 GAD negative diabetic patients, 59 of Yemenite and 62 of non-Yemenite origin, treated by diet ± oral antihyperglycemic monotherapy who underwent 180-min meal tolerance test (MMT). Based on MMT, indexes of insulin resistance and secretion were calculated.

RESULTS

There were no significant differences in age, sex, diabetes duration, BMI, HbA1c and lipid profile. A significant difference was found in family history of diabetes: 63 % of patients of Yemenite origin had maternal inheritance versus 35 % in the non-Yemenite origin (p < 0.001). Both indexes of β-cell function, the insulinogenic and the disposition indexes were significantly lower in patients of Yemenite origin compared with non-Yemenite origin (0.66 ± 0.4 vs. 0.93 ± 0.8, p = 0.04; 2.3 ± 1.8 vs. 3.3 ± 3.3, p = 0.04, respectively) with no difference in insulin sensitivity. When females and males were analyzed separately, the difference in maternal inheritance remained significant in both, but the difference in β-cell function indexes was observed only in males (p = 0.03, p = 0.01, respectively).

CONCLUSIONS

Males with recent-onset diabetes of Yemenite origin have a significant reduction of β-cell function and reduced ability to compensate for insulin resistance compared with diabetic males of non-Yemenite origin. Both males and females of Yemenite origin have a significantly higher maternal inheritance of diabetes. These data suggest different underlying mechanisms leading to early loss of β-cell in diabetic males of Yemenite origin.

Comparison between New-Onset and Old-Diagnosed Type 2 Diabetes with Ketosis in Rural Regions of China

Objectives. Type 2 diabetes (T2D) with ketosis was common because of late diagnosis and lacking adequate treatment in rural regions of China. This study aimed to provide the data of T2D with ketosis among inpatients in a south-west border city of China. Methods. Data of 371 patients of T2D with ketosis who were hospitalized between January 2011 and July 2015 in Baoshan People's Hospital, Yunnan, China, were analyzed. New-onset and old-diagnosed T2D patients presenting with ketosis were compared according to clinical characteristics, laboratory results, and chronic diabetic complications. Results. Overall, the blood glucose control was poor in our study subjects. Male predominated in both groups (male prevalence was 68% in new-onset and 64% in old-diagnosed groups). Overweight and obesity accounted for 50% in new-onset and 46% in old-diagnosed cases. Inducements of ketosis were 13.8% in new-onset and 38.7% in old-diagnosed patients. Infections were the first inducements in both groups. The prevalence of chronic complications of diabetes was common in both groups. Conclusions. More medical supports were needed for the early detection and adequate treatment of diabetes in rural areas of China.

Male predominance in ketosis-prone diabetes mellitus

The incidence of ketosis-prone diabetes mellitus (KPDM) shows a higher prevalence in men. The clear male predominance of this syndrome and its underlying pathogenesis mechanisms are unclear. KPDM, once described as atypical diabetes mellitus, idiopathetic type 1 diabetes (type 1B diabetes) and flatbush diabetes, is an uncommon form of diabetes characterized by severe reversible insulin deficiency. KPDM was first described and mostly observed in males of African-American descent and recently in Asian populations, including Japanese and Chinese. Patients with KPDM often present acutely with diabetic ketoacidosis without any immunological autoantibody to islet antigens of classic type 1 diabetes but demonstrate clinical and metabolic features of type 2 diabetes. Accumulating data indicated that gender-related body fat distribution, hormonal and genetic factors are associated with the diabetic process and the human glucose homeostasis and metabolism. A controversial question is whether and to what degree those factors contribute to the phenomenon of male predominance in KPDM. The present review focuses on the role of gender hormones and other potential precipitating factors in explaining the male predominance in KPDM patients.

Should diabetic ketosis without acidosis be included in ketosis-prone type 2 diabetes mellitus?

BACKGROUND

The incidence of ketosis-prone type 2 diabetes is very low except for people of sub-Saharan African origin and African Americans. However, there also are some type 2 diabetes patients with diabetic ketosis without acidosis (DKWA). We question whether DKWA should be included as a subtype of ketosis-prone type 2 diabetes mellitus and compared the clinical characteristics of DKWA and diabetic ketoacidosis (DKA) patients.

METHODS

The study population consisted of 594 consecutive unrelated Chinese inpatients with newly diagnosed type 2 diabetes. Demographic and clinical characteristics (age, gender, family history of diabetes, body mass index, blood pressure and plasma lipid parameters) were recorded. The patients were divided into ketosis-resistant diabetes (KRD), DKWA and DKA groups on the basis of urinary ketones, blood pH and bicarbonate levels. The blood glucose and c-peptide levels of the patients were also evaluated.

RESULTS

The prevalence of KRD, DKWA and DKA were 78.33%, 19.72% and 1.95%, respectively, in the study population. The clinical characteristics of patients with DKWA group patients were similar to those with DKA, except that DKA patients had higher blood glucose and deteriorated β cell function.

CONCLUSIONS

Diabetic ketosis without acidosis and DKA patients share similar clinical characteristics; DKWA should be considered ketosis-prone type 2 diabetes. Therefore, the prevalence of ketosis-prone type 2 diabetes might be underestimated.

Clinical characteristics and insulin independence of Koreans with new-onset type 2 diabetes presenting with diabetic ketoacidosis

BACKGROUND

We evaluated the incidence, characteristics and insulin independence of Koreans with new-onset type 2 diabetes (T2D) initially presenting with diabetic ketoacidosis (DKA).

METHODS

We analysed clinical and biochemical data from diabetic patients presenting with DKA. They were classified into ketosis-prone diabetes (KPD) type 1A (KPD-T1A) (A+β-), type 1B (KPD-T1B) (A-β-), type 2A (KPD-T2A) (A+β+) or type 2B (KPD-T2B) (A-β+) according to the presence or absence of an autoantibody and β-cell reserve. Changes in therapy after insulin discontinuation were evaluated for up to 4 years. We also compared clinical and biochemical characteristics between newly diagnosed T2D patients presenting with DKA and previously diagnosed T2D patients presenting with DKA.

RESULTS

Among 60 newly diagnosed KPD patients, 18, 21 and 21 patients were classified as KPD-T1A, KPD-T1B and KPD-T2B, respectively. In the KPD-T2B group, both fasting and stimulated C-peptide were recovered over 6 months. After 4 years of DKA development, 75% of KPD-T2B subjects no longer required insulin. Compared with previously diagnosed T2D patients presenting with DKA, newly diagnosed KPD-T2B patients tended to be younger, more obese and showed better insulin secretory function after recovery from DKA.

CONCLUSIONS

New-onset T2D patients presenting with DKA was not uncommon among the Korean population. In contrast to previously diagnosed T2D patients presenting with DKA, who showed a progressive decrease in insulin secretory function, new-onset KPD-T2B patients recovered insulin secretory function over time, and insulin independence could be expected.

Clinical, immunologic and insulin secretory characteristics of young black South African patients with diabetes: Hospital based single centre study

AIMS

To classify and characterize the clinical features of various diabetes classes among young black South Africans.

METHODS

Cross sectional study of 60 black patients with diabetes, all less than 30 years of age and attending Nelson Mandela Academic Hospital, Mthatha, South Africa. Diabetes was classified as Types 1A, 1B and 2 based on the anti-glutamic acid decarboxylase status and serum C-peptide response to intravenous injection of glucagon.

RESULTS

Mean age was 19.6±4.8 years (n=60) with similar gender distribution. The mean duration of diabetes was 24.2±45.1 months. Type 1A was the class of diabetes in 55% (n=33/60) of patients. Type 1B and 2 accounted for 30% (n=18/60) and 15% (n=9/60) of patients respectively. Patients classified as Type 2 had higher waist circumference and higher prevalence of acanthosis nigricans than Types 1A and 1B groups. History of diabetes in a first degree relative and hypertension were found in similar proportions of patients with Types 1A, 1B and 2 diabetes. Five Type 1A diabetes patients had body mass index of 26.2-41kg/m(2) and this included two newly diagnosed patients with body mass index of 26.7kg/m(2) and 33.2kg/m(2).

CONCLUSION

The majority of our young black South Africans with diabetes are of the Type 1A class. Acanthosis nigricans was not found in any patient with Type 1 A diabetes. A minority of Type 1 A diabetes patients were obese at initial diagnosis.

Prevalence and clinical characteristics of carotid atherosclerosis in newly diagnosed patients with ketosis-onset diabetes: a cross-sectional study

Background

The features of carotid atherosclerosis in ketosis-onset diabetes have not been investigated. Our aim was to evaluate the prevalence and clinical characteristics of carotid atherosclerosis in newly diagnosed Chinese diabetic patients with ketosis but without islet-associated autoantibodies.

Methods

In total, 423 newly diagnosed Chinese patients with diabetes including 208 ketosis-onset diabetics without islet-associated autoantibodies, 215 non-ketotic type 2 diabetics and 79 control subjects without diabetes were studied. Carotid atherosclerosis was defined as the presence of atherosclerotic plaques in any of the carotid vessel segments. Carotid intima-media thickness (CIMT), carotid atherosclerotic plaque formation and stenosis were assessed and compared among the three groups based on Doppler ultrasound examination. The clinical features of carotid atherosclerotic lesions were analysed, and the risk factors associated with carotid atherosclerosis were evaluated using binary logistic regression in patients with diabetes.

Results

The prevalence of carotid atherosclerosis was significantly higher in the ketosis-onset diabetic group (30.80%) than in the control group (15.2%, p=0.020) after adjusting for age- and sex-related differences, but no significant difference was observed in comparison to the non-ketotic diabetic group (35.8%, p=0.487). The mean CIMT of the ketosis-onset diabetics (0.70±0.20 mm) was markedly higher than that of the control subjects (0.57±0.08 mm, p<0.001), but no significant difference was found compared with the non-ketotic type 2 diabetics (0.73±0.19 mm, p=0.582) after controlling for differences in age and sex. In both the ketosis-onset and the non-ketotic diabetes, the prevalence of carotid atherosclerosis was markedly increased with age (both p<0.001) after controlling for sex, but no sex difference was observed (p=0.479 and p=0.707, respectively) after controlling for age. In the ketosis-onset diabetics, the presence of carotid atherosclerosis was significantly associated with age, hypertension, low-density lipoprotein cholesterol and mean CIMT.

Conclusions

The prevalence and risk of carotid atherosclerosis were significantly higher in the ketosis-onset diabetics than in the control subjects but similar to that in the non-ketotic type 2 diabetics. The characteristics of carotid atherosclerotic lesions in the ketosis-onset diabetics resembled those in the non-ketotic type 2 diabetics. Our findings support the classification of ketosis-onset diabetes as a subtype of type 2 diabetes.

Atypical diabetes in children: ketosis-prone type 2 diabetes

Ketosis-prone type 2 diabetes mellitus also known as atypical or flatbush diabetes is being increasingly recognised worldwide. These patients are typically obese, middle-aged men with a strong family history of type 2 diabetes. The aetiology and pathophysiological mechanism is still unclear but some initial research suggests that patients with ketosis-prone type 2 diabetes have a unique predisposition to glucose desensitisation. These patients have negative autoantibodies typically associated with type 1 diabetes but have shown to have human leucocyte antigen (HLA) positivity. At initial presentation, there is an impairment of both insulin secretion and action. β Cell function and insulin sensitivity can be markedly improved by initiating aggressive diabetes management to allow for discontinuation of insulin therapy within a few months of treatment. These patients can be maintained on oral hypoglycaemic agents and insulin therapy can be safely discontinued after few months depending on their β cell function.

Characteristics of diabetic ketoacidosis in Chinese adults and adolescents -- a teaching hospital-based analysis

OBJECTIVE

To investigate the diabetic ketoacidosis (DKA) episodes occurred in diabetic adults and adolescents.

METHODS

We reviewed diabetic patients of admissions with DKA in West China Hospital in Chengdu from January 1, 2008 to December 31, 2008. Clinical and laboratory data including β-cell function and autoantibody status were collected respectively. Patients were classified as having type 1 or type 2 diabetes or atypical diabetes based on clinical diagnosis and treatment history. And groups were compared for differences in vital statistics and biochemical profiles at presentation.

RESULTS

Detailed and accurate information was obtained in relation to 263 of patients accounted for the 287 admissions admitted for DKA, of whom 41 patients had type 1 diabetes (15.59%) meanwhile 178 patients were diagnosis as T2DM (67.68%), and 37 patients could not be "typed" were classified as atypical DM (14.07%). In addition, there were two gestational diabetes mellitus (GDM) and five patients with other specific types. Sixty admissions (22.81%) were newly diagnosed diabetes, of which 28 admissions (46.67%) were atypical diabetes. The most common contributing factor for DKA was infection (39.16%), followed by noncompliance with anti-diabetes treatment including omission of insulin (25.5%), unknown causes (25.86%) and other medical conditions (11.73%). Of note, these middle-age obese male patients with atypical diabetes often lapse into diabetic ketoacidosis without identifiable precipitating factors.

CONCLUSIONS

DKA could occur not only in T1DM but also in patients with T2DM under infection or stress condition, furthermore without any identifiable precipitant. The prevalence of DKA and its clinical heterogeneity have significant implications for diagnosing and classification of diabetes. More attention and prevention strategies are needed in ketosis-prone atypical diabetes.

Do obese children with diabetic ketoacidosis have type 1 or type 2 diabetes?

OBJECTIVE

Many obese children with unprovoked diabetic ketoacidosis (DKA) display clinical features of type 2 diabetes during follow up. We describe the clinical presentation, autoimmune markers and the long-term course of obese and lean children with DKA.

RESEARCH DESIGN AND METHODS

We reviewed the medical records on the initial acute hospitalization and outpatient follow-up care of 21 newly diagnosed obese and 20 lean children with unprovoked DKA at Emory University affiliated children's hospitals between 1/2003 and 12/2006.

RESULTS

Obese children with DKA were older and predominantly male, had acanthosis nigricans, and had lower prevalence of autoantibodies to islet cells and glutamic acid decarboxylase than lean children. Half of the obese, but none of the lean children with DKA achieve near-normoglycemia remission and discontinued insulin therapy during follow-up. Time to achieve remission was 2.2±2.3 months. There were no differences on clinical presentation between obese children who achieved near-normoglycemia remission versus those who did not. The addition of metformin to insulin therapy shortly after resolution of DKA resulted in lower hemoglobin A1c (HbA1c) levels, higher rates of near-normoglycemia remission, and lower frequency of DKA recurrence. Near-normoglycemia remission, however, was of short duration and the majority of obese patients required reinstitution of insulin treatment within 15 months of follow-up.

CONCLUSION

In contrast to lean children with DKA, many obese children with unprovoked DKA display clinical and immunologic features of type 2 diabetes during follow-up. The addition of metformin to insulin therapy shortly after resolution of DKA improves glycemic control, facilitates achieving near-normoglycemia remission and prevents DKA recurrence in obese children with DKA.

Update on diagnosis, pathogenesis and management of ketosis-prone Type 2 diabetes mellitus

Diabetic ketoacidosis (DKA) has been considered a key clinical feature of Type 1 diabetes mellitus; however, increasing evidence indicates that DKA is also a common feature of Type 2 diabetes (T2DM). Many cases of DKA develop under stressful conditions such as trauma or infection but an increasing number of cases without precipitating cause have been reported in children and adults with T2DM. Such patients present with severe hyperglycemia and ketosis as in Type 1 diabetes mellitus but can discontinue insulin after a few months and maintain acceptable glycemic control on diet or oral agents. This subtype of diabetes has been referred to as ketosis-prone T2DM. In this article, we reviewed the literature on ketosis-prone T2DM and summarized the epidemiology, putative pathophysiology and approaches to management.

Gender and neurogenin3 influence the pathogenesis of ketosis-prone diabetes

Ketosis-prone diabetes (KPD) is a phenotypically defined form of diabetes characterized by male predominance and severe insulin deficiency. Neurogenin3 (NGN3) is a proendocrine gene, which is essential for the fate of pancreatic beta cells. Mice lacking ngn3 develop early insulin-deficient diabetes. Thus, we hypothesized that gender and variants in NGN3 could predispose to KPD. We have studied clinical and metabolic parameters according to gender in patients with KPD (n = 152) and common type 2 diabetes (T2DM) (n = 167). We have sequenced NGN3 in KPD patients and screened gene variants in T2DM and controls (n = 232). In KPD, male gender was associated with a more pronounced decrease in beta-cell insulin secretory reserve, assessed by fasting C-peptide [mean (ng/ml) +/- s.d., M: 1.1 +/- 0.6, F: 1.5 +/- 0.9; p = 0.02] and glucagon-stimulated C-peptide [mean (ng/ml) +/- s.d., M: 2.2 +/- 1.1, F: 3.1 +/- 1.7; p = 0.03]. The rare affected females were in an anovulatory state. We found two new variants in the promoter [-3812T/C (af: 2%) and -3642T/C (af: 1%)], two new coding variants [S171T (af: 1%) and A185S (af: 1%)] and the variant already described [S199F (af: 69%)]. These variants were not associated with diabetes. Clinical investigation revealed an association between 199F and hyperglycaemia assessed by glycated haemoglobin [HbA1c (%, +/-s.d.) S199: 12.6 +/- 1.6, S199F: 12.4 +/- 1.4 and 199F: 14.1 +/- 2.2; p = 0.01]. In vitro, the P171T, A185S and S199F variants did not reveal major functional alteration in the activation of NGN3 target genes. In conclusion, male gender, anovulatory state in females and NGN3 variations may influence the pathogenesis of KPD in West Africans. This has therapeutic implications for potential tailored pharmacological intervention in this population.

Syndromes of ketosis-prone diabetes mellitus

Ketosis-prone diabetes (KPD) is a widespread, emerging, heterogeneous syndrome characterized by patients who present with diabetic ketoacidosis or unprovoked ketosis but do not necessarily have the typical phenotype of autoimmune type 1 diabetes. Multiple, severe forms of beta-cell dysfunction appear to underlie the pathophysiology of KPD. Until recently, the syndrome has lacked an accurate, clinically relevant and etiologically useful classification scheme. We have utilized a large, longitudinally followed, heterogeneous, multiethnic cohort of KPD patients to identify four clinically and pathophysiologically distinct subgroups that are separable by the presence or absence of beta-cell autoimmunity and the presence or absence of beta-cell functional reserve. The resulting "Abeta" classification system of KPD has proven to be highly accurate and predictive of such clinically important outcomes as glycemic control and insulin dependence, as well as an aid to biochemical and molecular investigations into novel causes of beta-cell dysfunction. In this review, we describe the current state of knowledge in regard to the natural history, pathophysiology, and treatment of the subgroups of KPD, with an emphasis on recent advances in understanding their immunological and genetic bases.

[Heterogeneity of type 1 diabetes mellitus]

Type 1 diabetes (T1D) comprises all forms of autoimmune-mediated and idiopathic beta-cell destruction leading to absolute insulin deficiency. The etiological heterogeneity of T1D has been recognized for the last decades, but it has been divided into only two subtypes so far: autoimmune (T1D)A and non-autoimmune (T1D)B mediated. Polygenic T1DA (isolated or associated to other autoimmune diseases) is the most prevalent type of T1D. T1DA might be part of rare monogenic syndromes related to mutations in the autoimmune regulator gene (AIRE) and FOXp3. Non-autoimmune forms of T1D correspond to approximately 4 to 7% of newly diagnosed T1D and include T1DB, as well as other types of atypical diabetes, for example fulminant type 1 diabetes and adult ketosis-prone diabetes. A new expression of diabetes in young with insulin resistance and obesity, along with the presence of pancreatic autoimmunity markers, namely auto-antibodies to islet cell antigens, is called double diabetes (DD), T1DA plus type 2 diabetes. Evidence has been collected concerning the potential effect of obesity-linked cytokines in amplifying the autoimmune response in DD. Therefore all these issues are presented and discussed in this review as the concept of heterogeneity of Type 1 Diabetes.

Prevalence and clinical features of type 1.5 diabetes mellitus in children

AIM

To classify children with diabetes mellitus as type 1, 1.5 or 2, based on strict criteria, and then compare their features and treatment.

METHODS

In this retrospective study, all children with diabetes mellitus in our clinic with antibody status available (n = 120) were reclassified as type 1, 1.5 or type 2 based on status of antibodies to the pancreas and presence of obesity and/or acanthosis nigricans, and their features compared.

RESULTS

Sixty-four percent of type 2 patients were reclassified as type 1.5. Type 1.5 patients had significantly lower BMI SDS, blood pressure and acanthosis nigricans than type 2 patients. They had a higher insulin requirement (0.82 +/- 0.44 U/kg/day) than type 1 (0.72 +/- 0.35 U/kg/day) or type 2 (0.28 +/- 0.3 U/kg/day) patients. Total cholesterol, HDL-cholesterol, ALT and AST significantly worsened from type 1 to 1.5 to type 2 patients.

CONCLUSIONS

Type 1.5 diabetes mellitus should be considered among obese adolescents presenting as type 2, as their clinical course is more aggressive and insulin requirement higher.

[Ketosis-prone atypical diabetes mellitus: report of two cases]

An atypical presentation of diabetes mellitus was described in black subjects, initially in adolescents by Winter et al. then, in adult populations. The principal characteristics of "African" diabetes are an acute onset with severe hyperglycemia and ketosis, and a clinical course of type 2 diabetes mellitus. In the subsequent clinical course after initiation of insulin therapy, prolonged remission is often possible with cessation of insulin therapy and maintenance of appropriate metabolic control. In the subsequent clinical course after initiation of insulin therapy, prolonged remission is often possible with cessation of insulin therapy and maintenance of appropriate metabolic control. The molecular mechanisms underlining the insulin secretory dysfunction are still to be understood and may involve glucolipotoxicity processes. The HLA alleles associated with susceptibility to type 1 diabetes were reported of high frequency in some populations with this form of diabetes, in the absence of makers of pancreatic beta cell autoimmunity. The aim of the present review is to discuss two cases of African diabetes and review the specific diagnostic, metabolic, pathogenic and management features of this atypical diabetes.

Ketosis-prone type 2 diabetes: effect of hyperglycemia on beta-cell function and skeletal muscle insulin signaling

OBJECTIVE

To determine the underlying mechanism for the severe and transient beta-cell dysfunction and impaired insulin action in obese African American patients with ketosis-prone diabetes.

METHODS

The effect of sustained hyperglycemia (glucotoxicity) and increased free fatty acids (lipotoxicity) on beta-cell function was assessed by changes in insulin secretion during a 20-hour glucose (200 mg/m2 per minute) and a 48-hour Intralipid (40 mL/h) infusion, respectively. Insulin-activated signaling pathways and pattern of Akt-1 and Akt-2 expression and insulin-stimulated phosphorylation were analyzed in skeletal muscle biopsy specimens. Studies were performed in an obese African American woman within 48 hours after resolution of diabetic ketoacidosis and 1 week after discontinuation of insulin treatment.

RESULTS

Dextrose infusion rapidly increased C-peptide levels from a baseline of 3.2 ng/mL to a mean of 7.1 +/- 0.5 ng/mL during the first 8 hours of infusion; thereafter, C-peptide levels progressively declined. Lipid infusion was not associated with any deleterious effect on insulin and C-peptide secretion. Initial in vitro stimulation of muscle tissue with insulin resulted in a substantial and selectively decreased Akt-2 expression and insulin-stimulated phosphorylation on the serine residue. Improved metabolic control resulted in 70% greater Akt expression at near-normoglycemic remission in comparison with the period of hyperglycemia.

CONCLUSION

Hyperglycemia, but not increased free fatty acid levels, led to progressive beta-cell dysfunction and impaired insulin secretion. Hyperglycemia was also associated with diminished skeletal muscle Akt expression and phosphorylation in an African American woman with ketosis-prone diabetes, and this defect improved notably with aggressive insulin therapy. These results indicate the importance of glucose toxicity in the pathogenesis of ketosis-prone diabetes in obese African American patients.

Accuracy and predictive value of classification schemes for ketosis-prone diabetes

OBJECTIVE

Ketosis-prone diabetes (KPD) is an emerging, heterogeneous syndrome. A sound classification scheme for KPD is essential to guide clinical practice and pathophysiologic studies. Four schemes have been used and are based on immunologic criteria, immunologic criteria and insulin requirement, BMI, and immunologic criteria and beta-cell function (Abeta classification). The aim of the present study is to compare the four schemes for accuracy and predictive value in determining whether KPD patients have absent or preserved beta-cell function, which is a strong determinant of long-term insulin dependence and clinical phenotype.

RESEARCH DESIGN AND METHODS

Consecutive patients (n = 294) presenting with diabetic ketoacidosis and followed for 12-60 months were classified according to all four schemes. They were evaluated longitudinally for beta-cell autoimmunity, clinical and biochemical features, beta-cell function, and insulin dependence. beta-Cell function was defined by peak plasma C-peptide response to glucagon >or=1.5 ng/ml. The accuracy of each scheme to predict absent or preserved beta-cell function after 12 months of follow-up was tested using multiple statistical analyses.

RESULTS

The "Abeta" classification scheme was the most accurate overall, with a sensitivity and specificity of 99.4 and 95.9%, respectively, positive and negative likelihood ratios of 24.55 and 0.01, respectively, and an area under the receiver operator characteristic curve of 0.972.

CONCLUSIONS

The Abeta scheme has the highest accuracy and predictive value in classifying KPD patients with regard to clinical outcomes and pathophysiologic subtypes.

Comparison of type 1, type 2, and atypical ketosis-prone diabetes at 4 years of diabetes duration

CONTEXT

Atypical ketosis-prone diabetes (KPD) is frequently detected in obese individuals at diagnosis of diabetes, yet its precise pathophysiology is not understood.

AIM

The hypothesis tested in this study states that while individuals with atypical KPD are phenotypically similar to those with type 2 diabetes, metabolically, they behave more like individuals with autoimmune type 1 diabetes.

METHODS

Thirty-seven individuals of Black, Hispanic, or White background and a diagnosis of diabetes mellitus for an average duration of 4 years participated in this cross-sectional study. Ten, 12, and 15 subjects had type 1, atypical, and type 2 diabetes, respectively. Insulin secretion was evaluated by a mixed-meal test. Insulin sensitivity and fuel oxidation were assessed by simultaneous euglycemic hyperinsulinemic clamp and indirect calorimetry. Lastly, a 12-h insulin withdrawal test was performed.

RESULTS

Insulin secretion, insulin sensitivity, and the insulin withdrawal tests yielded significant differences for type 1 vs. atypical diabetes and type 1 vs. type 2 diabetes, while there were no significant differences between atypical vs. type 2 diabetes. The indirect calorimetry showed higher-than-normal basal nonprotein respiratory quotients (RQs) and lower-than-normal insulin-stimulated nonprotein RQs across the three study groups.

CONCLUSIONS

After 4 years from diabetes diagnosis and while far from optimal glycemic control, atypical KPD resembles type 2 diabetes phenotypically and metabolically as well. Therefore, this study supports the classification of atypical KPD as ketosis-prone type 2 diabetes, and the concept that metabolic inflexibility occurs in the presence of insulin resistance in type 1 and type 2 diabetes.

Type 1 diabetes in Japan

Type 1 diabetes is a multifactorial disease which results from a T-cell-mediated autoimmune destruction of the pancreatic beta cells in genetically predisposed individuals. The risk for individuals of developing type 1 diabetes varies remarkably according to country of residence and race. Japan has one of the lowest incidence rates of type 1 diabetes in the world, and recognises at least three subtypes of the condition: acute-onset ('classical'), slow-onset, and fulminant type 1 diabetes. The incidence rate of type 1 diabetes in children aged 0-14 years in Japan increased over the period from 1973-1992, but remained constant over the last decade, averaging 2.37 cases per 100,000 persons per year; the incidence does not appear to have increased in older age groups. Although there are few reports regarding the incidence and prevalence of type 1 diabetes in adult-onset patients, it appears that the prevalence of type 1 diabetes in adults is more than twice that in childhood-onset patients and that two-thirds of them have a slow-onset form of type 1 diabetes. Differences and similarities in the association of MHC and non-MHC genes with type 1 diabetes are observed in Japan and in countries with Caucasoid populations. Highly susceptible class II HLA haplotypes identified in patients of Caucasoid origin are rarely seen in Japanese patients, whereas protective haplotypes are universal. Non-MHC genes associated with susceptibility to type 1 diabetes in both Japanese and Caucasoid patients include polymorphisms in the insulin gene, the cytotoxic T-lymphocyte antigen 4 (CTLA4) gene, the interleukin-18 (IL18) gene and the major histocompatibility complex class I chain-related gene A (MICA) gene. Fulminant type 1 diabetes is a unique subtype of type 1 diabetes that accounts for about 20% of acute-onset type 1 diabetes, and is seen mainly in adults. The challenge for the future is to investigate the underlying pathogenesis of beta cell destruction, including the genetic or environmental factors that may modify the form of onset for each subtype of Japanese type 1 diabetes.

Islet autoimmunity and genetic mutations in Chinese subjects initially thought to have Type 1B diabetes

AIMS

To explore the contribution of islet autoimmunity and genetic mutations in Chinese patients initially thought to have Type 1B diabetes.

METHODS

A group of 33 Chinese patients with newly diagnosed Type 1B diabetes, were identified by the absence of autoantibodies to glutamic acid decarboxylase (GAD), IA-2, insulin, thyroid globulin or thyroid peroxidase, or high-risk HLA-DQ haplotypes. The cohort was further characterized by measurement of autoantibodies to carboxypeptidase H (CPH) and SOX13 using radioligand assays, and testing for genetic mutations associated with MODY3/MODY6 and mitochondrial diabetes. Mutations of HNF-1alpha (MODY3) and neuroD1/beta2 (MODY6) genes were screened using the single-strand conformation polymorphism (SSCP) technique and sequencing. Mitochondrial DNA mutations were analysed with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

Within the cohort, we found one patient with a novel mutation, R321H (CGC-->CAC) in exon 5 of the HNF-1alpha gene, one with ND1 mt3316 G-->A mutation in mitochondrial DNA, five with Ala45Thr polymorphisms in the neuroD1/beta2 gene, and two patients with autoantibodies to SOX13.

CONCLUSIONS

Some of the Chinese patients originally thought to have Type 1B diabetes do have other evidence of islet autoimmunity and genetic mutations involved in the underlying aetiology. This suggests that more rigorous screening for these conditions is needed before classifying subjects as having Type 1B diabetes.

Prevalence and characteristics of type 2 diabetes mellitus in 9-18 year-old children with diabetic ketoacidosis

OBJECTIVE

To estimate the prevalence of type 2 diabetes mellitus (DM2) in 9-18 year-old children with diabetic ketoacidosis (DKA) and to describe the presenting biochemical characteristics and response to standardized DKA treatment.

METHODS

Data were collected from a consecutive sample of 9-18 year-old children presenting with DKA. DKA was defined as hyperglycemia and ketosis with an initial pH <7.3, or bicarbonate <15 mmol/l. Patients were classified as having DM2 if they had negative autoantibody status and normal or elevated fasting C-peptide.

RESULTS

The prevalence of DM2 in patients with DKA was 13.0% (6.1-23.3%). There was no significant difference in the presenting pH (7.14 vs 7.15), but blood glucose was higher (735 vs 587 mg/dl) in patients with DM2, than in patients with type 1 DM (DM1). The duration of insulin infusion until resolution of acidosis (17.3 vs 13.2 h) and intensive care unit stay (2.4 vs 1.6 days) were longer in patients with DM2. Seven of the nine patients with DM2 did not require insulin at 1-year follow-up.

CONCLUSIONS

Children with DM2 can present with DKA and constitute a significant percentage in the above 9-year age group. The need for insulin must be carefully re-evaluated as DKA resolves in these patients. Adolescents with DM2 and their families need to be educated about DKA.

Is Type 1 diabetes in the Japanese population the same as among Caucasians?

In the Japanese population, the incidence of type 1 diabetes is as low as approximately 2 cases/year/100,000 children, which is much lower compared to that in countries with populations predominantly of Caucasian origin. However, the prevalences of anti-islet autoantibodies in patients with Japanese type 1 diabetes are 60-70% for GAD autoantibodies, 45-50% for insulin autoantibodies (IAA), and 60-65% for IA-2 autoantibodies at disease onset, which are similar to those reported in Caucasian patients. With combinatorial analysis of these autoantibodies, 90% of patients express at least one of these autoantibodies and are classified as type 1A diabetics. There is a significant number of patients with latent autoimmune diabetes in adults (LADA) in Japan, and a high level of GAD autoantibodies has a high predictive value for future insulin deficiency in such patients. Recently, it has been reported that a group of extremely rapid-onset patients presented with diabetic ketoacidosis and a low HbA1c level, called fulminant diabetes mellitus. Although they had severe hyperglycemia, these individuals lacked the expression of anti-islet autoantibodies. With a nationwide survey, it was documented that fulminant type 1 diabetes accounts for approximately 20% of the ketosis-onset patients with type 1 diabetes in Japan. It is currently unknown whether the pathogenesis of fulminant type 1 diabetes is associated with autoimmune response to pancreatic islet beta cells. Japanese patients with type 1 diabetes are clinically heterogeneous, and further investigations are required to clarify the underlying pathogenesis for each subgroup of type 1 diabetes.

Diabetes mellitus in a young Amazon Indian child

CONTEXT

Although type 2 diabetes has been described among American Indian children, no case of type 1 diabetes has been reported in the literature.

CASE REPORT

We report the first case of diabetes in a South American Indian child from the tropical rainforest, who was positive for IA2 autoantibodies and genetic markers of susceptibility to type 1 diabetes, but also demonstrated residual beta cell function four years after diagnosis.

Residual beta-cell function and male/female ratio are higher in incident young adults than in children: the registry of type 1 diabetes of the province of Turin, Italy, 1984-2000

OBJECTIVE

The hypothesis of age-dependent variations in epidemiologic and clinical features at onset of type 1 diabetes has been assessed in the registry of the province of Turin, Italy.

RESEARCH DESIGN AND METHODS

The study base is the population 0-29 years of age of the province of Turin, in the period from 1984 to 2000. Islet cell antibody (ICA), GAD antibody (GADA), antibodies to protein tyrosine phosphatase (IA2), and C-peptide were measured in subgroups of the cohort.

RESULTS

One thousand fifty-six incident cases have been identified (completeness of ascertainment 98.1%). Rates per 100,000 person-years were similar in males and females in the age-group 0-14 years (10.7, 95% CI 9.5-12.0 vs. 9.8, 8.6-11.1). In the age-group 15-29 years, males had higher risk than females (7.7, 6.9-8.6 vs. 5.3, 4.6-6.1; rate ratio, 1.46, 95% CI 1.23-1.74; P = 0.00002). Fasting plasma C-peptide values (n = 575) were twofold lower in the age-group 0-14 years than in the age-group 15-29 years (0.10 vs. 0.23 nmol/l; P < 0.0001). Frequencies of ICA and IA2 positivities (n = 183) decreased with increasing age, whereas frequency of GADA positivity increased. Idiopathic cases were 12.6% and had higher mean values of fasting (0.28 vs. 0.14 nmol/l; P = 0.043) and stimulated C-peptide (0.59 vs. 0.34 nmol/l; P = 0.05). In logistic regression analyses, subjects with fasting C-peptide values in the upper quartile had higher likelihood of being older (odds ratio 1.20 for year, 95% CI 1.11-1.28), ICA negative (0.26, 0.10-0.70), and female (1.29, 0.48-3.42).

CONCLUSIONS

This study shows 1) sex differences in incidence rates in young adults; 2) better preserved beta-cell function in young adults, in idiopathic cases (12%), and in ICA-negative cases; and 3) lower frequencies of ICA and IA2 positivities and higher frequency of GADA positivity in young adults than in children.

PAX4 gene variations predispose to ketosis-prone diabetes

Ketosis-prone diabetes (KPD) is a rare form of type 2 diabetes, mostly observed in subjects of west African origin (west Africans and African-Americans), characterized by fulminant and phasic insulin dependence, but lacking markers of autoimmunity observed in type 1 diabetes. PAX4 is a transcription factor essential for the development of insulin-producing pancreatic beta-cells. Recently, a missense mutation (Arg121Trp) of PAX4 has been implicated in early and insulin deficient type 2 diabetes in Japanese subjects. The phenotype similarities between KPD and Japanese carriers of Arg121Trp have prompted us to investigate the role of PAX4 in KPD. We have screened 101 KPD subjects and we have found a new variant in the PAX4 gene (Arg133Trp), specific to the population of west African ancestry, and which predisposes to KPD under a recessive model. Homozygous Arg133Trp PAX4 carriers were found in 4% of subjects with KPD but not in 355 controls or 147 subjects with common type 2 or type 1 diabetes. In vitro, the Arg133Trp variant showed a decreased transcriptional repression of target gene promoters in an alpha-TC1.6 cell line. In addition, one KPD patient was heterozygous for a rare PAX4 variant (Arg37Trp) that was not found in controls and that showed a more severe biochemical phenotype than Arg133Trp. Clinical investigation of the homozygous Arg133Trp carriers and of the Arg37Trp carrier demonstrated a more severe alteration in insulin secretory reserve, during a glucagon-stimulation test, compared to other KPD subjects. Together these data provide the first evidence that ethnic-specific gene variants may contribute to the predisposition to this particular form of diabetes and suggest that KPD, like maturity onset diabetes of the young, is a rare, phenotypically defined but genetically heterogeneous form of type 2 diabetes.

Adult-onset atypical (type 1) diabetes: additional insights and differences with type 1A diabetes in a European Mediterranean population

OBJECTIVE

In 1997, the American Diabetes Association proposed two subcategories for type 1 diabetes: type 1A or immunomediated diabetes and type 1B or idiopathic diabetes characterized by negative beta-cell autoimmunity markers, lack of association with HLA, and fluctuating insulinopenia. The aim of this study was to examine clinical characteristics, beta-cell function, HLA typing, and mutations in maturity-onset diabetes of the young (MODY) genes in patients with atypical type 1 diabetes (type 1 diabetes diagnosed at onset, without pancreatic autoantibodies and fluctuating insulinopenia).

RESEARCH DESIGN AND METHODS

Eight patients with atypical type 1 diabetes (all men, 30.7 +/- 7.6 years) and 16 newly diagnosed age- and sex-matched patients with type 1A diabetes were studied retrospectively. Islet cell, GAD, tyrosine phosphatase and insulin antibodies, and basal and stimulated plasma C-peptide were measured at onset and after 1 year. HLA-DRB1-DQA1-DQB1 typing and screening for mutations in the HNF-1alpha and HNF-4alpha genes were performed from genomic DNA.

RESULTS

Atypical patients displayed significantly higher BMI and better beta-cell function at onset and after 12 months. Three patients carried protective or neutral type 1 diabetes haplotypes, five patients displayed heterozygosity for susceptible and protective haplotypes, and seven patients showed Asp(beta57). We found a nondescribed variant Pro436Ser in exon 10 of the HNF-4alpha gene in one atypical patient without susceptible haplotypes.

CONCLUSIONS

In our population, there are atypical forms of young adult-onset ketosis-prone diabetes initially diagnosed as type 1 diabetes, differing from type 1 diabetes in the absence of beta-cell autoimmunity, persistent beta-cell function capacity, fluctuating insulin requirements and ketosis-prone episodes, as well as clinical features of type 2 diabetes. Only one subgroup could be strictly classified as having type 1B diabetes. Additional information is still needed to improve our understanding of the mechanisms that finally lead to the disease.

Islet antibodies and remaining beta-cell function 8 years after diagnosis of diabetes in young adults: a prospective follow-up of the nationwide Diabetes Incidence Study in Sweden

OBJECTIVES

To establish the prevalence of remaining beta-cell function 8 years after diagnosis of diabetes in young adults and relate the findings to islet antibodies at diagnosis and 8 years later.

DESIGN

Population-based cohort study.

SETTING

Nationwide from all Departments of Medicine and Endocrinology in Sweden.

SUBJECTS

A total of 312 young (15-34 years old) adults diagnosed with diabetes during 1987-88.

MAIN OUTCOME MEASURE

Plasma connecting peptide (C-peptide) 8 years after diagnosis. Preserved beta-cell function was defined as measurable C-peptide levels. Three islet antibodies - cytoplasmic islet cell antibodies (ICA), glutamic acid decarboxylase antibodies and tyrosine phosphatase antibodies - were measured.

RESULTS

Amongst 269 islet antibody positives (ab+) at diagnosis, preserved beta-cell function was found in 16% (42/269) 8 years later and these patients had a higher body mass index (median 22.7 and 20.5 kg m-2, respectively; P = 0.0003), an increased frequency of one islet antibody (50 and 24%, respectively; P = 0.001), and a lower prevalence of ICA (55 and 6%, respectively; P = 0.007) at diagnosis compared with ab+ without remaining beta-cell function. Amongst the 241 patients without detectable beta-cell function at follow-up, 14 lacked islet antibodies, both at diagnosis and at follow-up.

CONCLUSIONS

Sixteen per cent of patients with autoimmune type 1 diabetes had remaining beta-cell function 8 years after diagnosis whereas 5.8% with beta-cell failure lacked islet autoimmunity, both at diagnosis and at follow-up.

Ketosis-prone type 2 diabetes in patients of sub-Saharan African origin: clinical pathophysiology and natural history of beta-cell dysfunction and insulin resistance

Nonautoimmune ketosis-prone diabetic syndromes are increasingly frequent in nonwhite populations. We have characterized a cohort of patients of sub-Saharan African origin who had ketosis-prone type 2 diabetes (n = 111), type 1 diabetes (n = 21), and type 2 diabetes (n = 88) and were admitted to a hospital for management of uncontrolled diabetes. We compared epidemiological, clinical, and metabolic features at diabetes onset and measured insulin secretion (glucagon-stimulated C-peptide) and insulin action (short intravenous insulin tolerance test) during a 10-year follow-up. Ketosis-prone type 2 diabetes shows a strong male predominance, stronger family history, higher age and BMI, and more severe metabolic decompensation than type 1 diabetes. In ketosis-prone type 2 diabetes, discontinuation of insulin therapy with development of remission of insulin dependence is achieved in 76% of patients (non-insulin dependent), whereas only 24% of patients remain insulin dependent. During evolution, ketosis-prone type 2 diabetes exhibit specific beta-cell dysfunction features that distinguish it from type 1 and type 2 diabetes. The clinical course of non-insulin-dependent ketosis-prone type 2 diabetes is characterized by ketotic relapses followed or not by a new remission. Progressive hyperglycemia precedes and is a strong risk factor for ketotic relapses (hazard ratio 38). The probability for non-insulin-dependent ketosis-prone type 2 diabetes to relapse is 90% within 10 years, of whom approximately 50% will become definitively insulin dependent. Insulin sensitivity is decreased in equal proportion in both ketosis-prone type 2 diabetes and type 2 diabetes, but improves significantly in non-insulin-dependent ketosis-prone type 2 diabetes, only after correction of hyperglycemia. In conclusion, ketosis-prone type 2 diabetes can be distinguished from type 1 diabetes and classical type 2 diabetes by specific features of clinical pathophysiology and also by the natural history of beta-cell dysfunction and insulin resistance reflecting a propensity to glucose toxicity.

Practical Management of Type 1 Diabetes Mellitus in Adolescent Patients

Type 1 diabetes mellitus in adolescents presents diagnostic and management challenges. Diagnostically, the challenge is to distinguish type 1 from type 2 diabetes. A thin adolescent in diabetic ketoacidosis is easily recognized as having type 1 diabetes. However, since obesity does not negate the presence of type 1 diabetes, it is appropriate to measure diabetes-related antibody, C-peptide, and insulin levels in individuals who are thought to have type 2 diabetes to ensure that they do not have type 1 or a mixed type of diabetes. The goals for the management of type 1 diabetes in adolescents are to (i) prevent diabetic ketoacidosis; (ii) prevent severe hypoglycemia; (iii) maintain normal growth and development; and (iv) prevent long-term diabetic complications. To prevent diabetic ketoacidosis, patients must take their insulin appropriately. To ensure that this happens, increased parental supervision, psychological counseling, or placement in a different home environment may be necessary. All patients must be taught to appropriately manage sick days and test their urine for ketones when hyperglycemia is present. Prevention of severe hypoglycemia involves ensuring that the patient understands the symptoms of hypoglycemia and knows to test and treat it when the signs are present. Patients and families also need to know how to adjust insulin doses to prevent hypoglycemia and how to manage exercise appropriately. Patients with hypoglycemic unawareness need to meticulously avoid hypoglycemia. To maintain normal growth and development, adolescents with type 1 diabetes must have the appropriate tools to effectively match their meals to their lifestyle and to avoid the increased weight gain associated with improved glycemic control without intentionally manipulating their insulin dose to lose weight. The Diabetes Control and Complications Trial demonstrated that improved glycemic control decreased the risk of long-term diabetic complications. The goals of treatment in this study should be the goals for all adolescents with type 1 diabetes. To reach these goals, home glucose monitoring is critical. Patients need to know how to adjust insulin to maintain glucose levels in the range of 70-120 mg/dL (3.9-6.7 mmol/L) before meals. Insulin regimens need to be individually tailored to meet each patient's needs. Patients should be followed in a clinic using a multidisciplinary team approach at least every 3 months. Glycosylated hemoglobin should be measured at each visit. Regular eye exams, blood pressure monitoring, and urinary microalbumin measurements are critical. In this manner, the goals of management of type 1 diabetes in adolescents can be met.

Ketosis-prone diabetes: dissection of a heterogeneous syndrome using an immunogenetic and beta-cell functional classification, prospective analysis, and clinical outcomes

Ketosis-prone diabetes is heterogeneous. Its causes could include novel beta-cell functional defects. To characterize such defects, 103 patients with diabetic ketoacidosis were evaluated for beta-cell autoimmunity and human leukocyte antigen (HLA) class II alleles, with longitudinal measurements of beta-cell function and biochemical and clinical parameters. They were classified into four A beta groups, based on the presence of glutamic acid decarboxylase (GAD)65, GAD67, or IA-2 autoantibodies (A+ or A-) and beta-cell functional reserve (beta+ or beta-). The group distribution was: 18 A+beta-, 23 A-beta-, 11 A+beta+, and 51 A-beta+. Collectively, the two beta- groups differed from the two beta+ groups in earlier onset and longer duration of diabetes, lower body mass index, less glycemic improvement, and persistent insulin requirement. HLA class II genotyping showed that the A-beta- group differed from the A+beta- group in having lower frequencies of two alleles strongly associated with autoimmune type 1 diabetes susceptibility: DQA*03 and DQB1*02. Similarly, the A-beta+ group differed from the A+beta+ group in having a lower frequency of DQB1*02. Ketosis-prone diabetes comprises at least four etiologically distinct syndromes separable by autoantibody status, HLA genotype, and beta-cell functional reserve. Novel, nonautoimmune causes of beta-cell dysfunction are likely to underlie the A-beta+ and A-beta- syndromes.