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

Prevalence and Gender Differences of Metabolic Syndrome in Young Ketosis-Prone Type 2 Diabetic Individuals: A Retrospective Study

PURPOSE

This study aimed to identify the prevalence and gender differences of metabolic syndrome in young new-onset ketosis-prone type 2 diabetic (KPT2D) individuals.

PATIENTS AND METHODS

A retrospective study was conducted in Shanghai Xin Hua Hospital from 2007 to 2019. A total of 304 patients from 12 to 40 years of age with newly diagnosed diabetes presenting with ketosis were analyzed. The clinical features and laboratory results of KPT2D and type 1 diabetic (T1D) individuals were compared. Prevalence and gender differences of metabolic syndrome in the KPT2D subjects were analyzed.

RESULTS

The prevalence of metabolic syndrome (P < 0.0001) was significantly higher in young KPT2D than T1D subjects. The prevalence of high blood pressure (P < 0.0001), central obesity (P < 0.0001), low plasma HDL-C concentration (P = 0.045), and hypertriglyceridemia (P < 0.0001) was elevated in the KPT2D subjects compared with T1D. Male predominance (89%) was presented in the KPT2D subjects. The prevalence of metabolic syndrome (P = 0.0002) was significantly higher in young male than female KPT2D subjects. The presence of central obesity (P < 0.0001) and high blood pressure (P =0.03) was higher in male KPT2D subjects than female. The presence of serum triglyceride concentrations ≥ 2.3mmol/L was significantly higher (P = 0.011) in male KPT2D subjects than female.

CONCLUSION

Significantly higher prevalence of metabolic syndrome in young KPT2D patients compared with T1D patients could be an important reference for diabetic differential diagnosis. KPT2D presented a higher predominance in young males, who had higher prevalence of metabolic syndrome than young females.

Uncommon Presentations of Diabetes: Zebras in the Herd

The majority of patients with diabetes are diagnosed as having either type 1 or type 2 diabetes. However, when encountered in clinical practice, some patients may not match the classic diagnostic criteria or expected clinical presentation for either type of the disease. Latent autoimmune, ketosis-prone, and monogenic diabetes are nonclassical forms of diabetes that are often misdiagnosed as either type 1 or type 2 diabetes. Recognizing the distinguishing clinical characteristics and understanding the diagnostic criteria for each will lead to appropriate treatment, facilitate personalized medicine, and improve patient outcomes.

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.

Two cases of ketosis-prone diabetes mellitus in Korean adolescents

In recent years, reports of diabetes mellitus (DM) cases that do not fit the traditional classification system have increased in prevalence. While insulin deficiency appears as type 1 DM (T1DM), the new type also has the clinical features of type 2 DM (T2DM); as such, this new type of DM is called ketosis-prone diabetes (KPD) and is correlated with findings of severe hyperglycemia and ketoacidosis. To provide a clear, clinical classification of DM, new classification systems are being studied. Among these, the Aβ system demonstrates the highest sensitivity and specificity in predicting clinical features and prognosis. We report 2 cases of KPD in Korean pediatric patients. The first patient was referred while in a state of diabetic ketoacidosis (DKA) and was considered to have T1DM. However, their blood glucose was well-controlled even with small doses of insulin, and the treatment was able to be changed to metformin therapy. The second patient seemed to be a typical case of T2DM because of his obesity and strong family history. However, blood glucose was not well-controlled with a regular diet, and ketosis occurred. After performing a glucagon stimulation test, both patients showed different clinical features that were finally diagnosed as type A-β+ KPD. The rapid and accurate diagnosis of KPD can reduce the duration of inappropriate insulin use and improve patients&apos; quality of life. Further, the treatment of KPD children should be individualized according to each patient's lifestyle to preventing recurrent DKA.

Atypical forms of diabetes mellitus in Africans and other non-European ethnic populations in low- and middle-income countries: a systematic literature review

BACKGROUND

Atypical presentations of diabetes mellitus (DM) have been reported in non-European ethnic populations under various names. It is unclear whether those names are used for the same or different clinical phenotypes. Unclear terminology may lead to inappropriate treatment and an underestimation of the burden caused by atypical diabetes phenotypes overlapping with classic types of diabetes. This review aimed to describe the terms used for atypical forms of diabetes and to investigate whether the terms are used for similar or different phenotypes.

METHODS

PubMed and Scopus were searched for relevant publications in French or English available before 15 September 2015 using the terms: "Atypical diabetes", "Malnutrition Related Diabetes Mellitus (MRDM)", "Fibro-calculus pancreatic diabetes (FCPD)", Protein deficient Pancreatic Diabetes (PDPD)", "African diabetes", "Ketosis prone-type 2 diabetes", "tropical diabetes", "Flatbush diabetes", "J-type diabetes". Titles, abstracts screening and quality assessment were performed by two independent authors. Observational studies addressing atypical diabetes in humans aged 14 years and above were included. One author extracted data from selected articles.

RESULTS

22 articles among 350 identified articles were retained for data extraction. Two atypical diabetes phenotypes were identified, each of them with a variety of names but similar definitions. One phenotype occurred in very thin people less than 30 years of age, typically from poor socio-economic backgrounds and requires insulin for life. It differs from type 1 diabetes in the tolerance of high blood glucose without ketosis in the absence of exogenous insulin. The second phenotype resembles type1 diabetes as it presents with ketosis at onset but responds well, as type2 diabetes, to oral hypoglycemic drugs after initial stabilization with insulin. It occurs in individuals who are usually over 30 years of age, with normal or overweight and absence of auto antibodies mainly found in type 1 diabetes.

CONCLUSION

The scarce existing literature used various terms for similar diabetes phenotypes. Agreement on nomenclature for the various forms of diabetes using the above reported characteristics are needed in populations where atypical forms of diabetes exist as well as better characterization of phenotypes and genotypes to inform evidence based treatment.

Community- and mHealth-based integrated management of diabetes in primary healthcare in Rwanda (D²Rwanda): the protocol of a mixed-methods study including a cluster randomised controlled trial

INTRODUCTION

In Rwanda, diabetes mellitus prevalence is estimated between 3.1% and 4.3%. To address non-communicable diseases and the shortage of health workforce, the Rwandan Ministry of Health has introduced the home-based care practitioners (HBCPs) programme: laypeople provide longitudinal care to chronic patients after receiving a six-month training. Leveraging technological mobile solutions may also help improve health and healthcare. The D²Rwanda study aims at: (a) determining the efficacy of an integrated programme for the management of diabetes in Rwanda, which will provide monthly patient assessments by HBCPs, and an educational and self-management mHealth patient tool, and; (b) exploring qualitatively the ways the interventions will have been enacted, their challenges and effects, and changes in the patients' health behaviours and HBCPs' work satisfaction.

METHODS AND ANALYSIS

This is a mixed-methods sequential explanatory study. First, there will be a one-year cluster randomised controlled trial including two interventions ((1) HBCPs' programme; (2) HBCPs' programme + mobile health application) and usual care (control). Currently, nine hospitals run the HBCPs' programme. Under each hospital, administrative areas implementing the HBCPs' programme will be randomised to receive intervention 1 or 2. Eligible patients from each area will receive the same intervention. Areas without the HBCPs' programme will be assigned to the control group. The primary outcome will be changes in glycated haemoglobin. Secondary outcomes include medication adherence, mortality, complications, health-related quality of life, diabetes-related distress and health literacy. Second, at the end of the trial, focus group discussions will be conducted with patients and HBCPs. Financial support was received from the Karen Elise Jensens Fond, and the Universities of Aarhus and Luxembourg.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the Rwanda National Ethics Committee and the Ethics Review Panel of the University of Luxembourg. Findings will be disseminated via peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

NCT03376607; Pre-results.

Ketosis prone diabetes presenting as fulminant type 1 diabetes

Patients with ketosis prone diabetes have been reported primarily in Africans and African Americans. At presentation, both insulin secretion and insulin action are impaired in ketosis prone diabetes patients. Fulminant diabetes is a subtype of type 1 diabetes reported mainly in the Asian populations characterized by diabetic ketosis or ketoacidosis occurring soon after the onset of hyperglycemic symptoms with inappropriately low HbA1c (< 8.5%). We report here the first case of a ketosis prone diabetes presenting as fulminant diabetes.

Understanding the manifestation of diabetes in sub Saharan Africa to inform therapeutic approaches and preventive strategies: a narrative review

BACKGROUND

Globally, the burden of diabetes mellitus has increased to epidemic proportions. Estimates from the International Diabetes Federation predict that the greatest future increase in the prevalence of diabetes mellitus will occur in Africa.

METHODS

This article reviews literature on the manifestation of diabetes in adult patients in sub-Saharan Africa highlighting the distinct phenotypes, plausible explanations for this unique manifestation and the clinical significance of comprehensively defining and understanding the African diabetes phenotype.

RESULTS

There are few studies on the manifestation or phenotype of diabetes in Africa. The limited data available suggests that, compared to the Western world, the majority of patients with diabetes in Africa are young and relatively lean in body size. In addition, hyperglycaemia in most cases is characterised by a significantly blunted acute first phase of insulin secretion in response to an oral or intravenous glucose load and pancreatic beta cell secretory dysfunction, rather than peripheral insulin resistance predominates. Genetic and environmental factors like chronic infections/inflammation, early life malnutrition and epigenetic modifications are thought to contribute to these distinct differences in manifestation.

CONCLUSIONS

While published data is limited, there appears to be distinct phenotypes of diabetes in sub-Saharan Africa. Large and more detailed studies are needed especially among newly diagnosed patients to fully characterize diabetes in this region. This will further improve the understanding of manifestation of diabetes and guide the formulation of optimal therapeutic approaches and preventive strategies of the condition on the continent.

Transgene-associated human growth hormone expression in pancreatic β-cells impairs identification of sex-based gene expression differences

Fluorescent protein reporter genes are widely used to identify and sort murine pancreatic β-cells. In this study, we compared use of the MIP-GFP transgene, which exhibits aberrant expression of human growth hormone (hGH), with a newly derived Ins2^Apple allele that lacks hGH expression on the expression of sex-specific genes. β-Cells from MIP-GFP transgenic mice exhibit changes in the expression of 7,733 genes, or greater than half of their transcriptome, compared with β-cells from Ins2^Apple/+ mice. To determine how these differences might affect a typical differential gene expression study, we analyzed the effect of sex on gene expression using both reporter lines. Six hundred fifty-seven differentially expressed genes were identified between male and female β-cells containing the Ins2^Apple allele. Female β-cells exhibit higher expression of Xist, Tmed9, Arpc3, Eml2, and several islet-enriched transcription factors, including Nkx2-2 and Hnf4a, whereas male β-cells exhibited a generally higher expression of genes involved in cell cycle regulation. In marked contrast, the same male vs. female comparison of β-cells containing the MIP-GFP transgene revealed only 115 differentially expressed genes, and comparison of the 2 lists of differentially expressed genes revealed only 17 that were common to both analyses. These results indicate that 1) male and female β-cells differ in their expression of key transcription factors and cell cycle regulators and 2) the MIP-GFP transgene may attenuate sex-specific differences that distinguish male and female β-cells, thereby impairing the identification of sex-specific variations.

Ketosis-Prone Type 2 Diabetes: A Case Series

Ketosis-prone type 2 diabetes ("Flatbush diabetes") carries features of both classical type 1 and type 2 diabetes and is highly prevalent in African populations. The disease, which is highly ketosis-prone, but neither chronically insulinopenic nor autoimmune, is discussed regarding pathogenesis, diagnosis and treatment from a patient case perspective.

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).

Human herpesvirus 8 infection DNA positivity is associated with low insulin secretion: A case-control study in a sub-Saharan African population with diabetes

BACKGROUND

Viruses have been considered potential triggers for the development of diabetes. This study assessed insulin secretion and insulin sensitivity in human herpesvirus 8 (HHV8)-infected and uninfected sub-Saharan African people with diabetes.

METHODS

In all, 173 people with non-autoimmune diabetes were enrolled consecutively: 124 with type 2 diabetes mellitus (T2DM) and 49 with ketosis-prone diabetes (KPD) admitted in hyperglycemic crisis. Those with KPD were further subdivided into those with new-onset ketotic-phase KPD (n = 34) or non-ketotic phase KPD (n = 15). All participants were screened for HHV8-specific antibodies and genomic DNA. Blood samples were collected for analysis of fasting glucose, HbA1c, lipid profile, and C-peptide, with insulin resistance and secretion estimated by homeostasis model assessment.

RESULTS

Among the 173 diabetic participants, 88 (50.9%) were positive for HHV8 antibodies (Ac-HHV8+), including 15 (8.7%) positive for HHV8 DNA (DNA-HHV8+). The seroprevalence of HHV8 was similar between T2DM (55.6%) and KPD (61.2%) subjects. Of those with and without ketotic-phase KPD, 35.3% and 46.7% were Ac-HHV8+, respectively. Body mass index was significantly in lower DNA-HHV8+ than DNA-HHV8- subjects. Low-density lipoprotein and total cholesterol were significantly higher, but C-peptide and homeostatic model assessment of β-cell function (HOMA-β) were significantly lower in DNA-HHV8+ than DNA-HHV8- participants. After excluding DNA-HHV8+ participants, triglyceride concentrations were significantly higher in Ac-HHV8+ (n = 73) than Ac-HHV8- (n = 85) subjects. In contrast, HOMA-β was significantly higher among Ac-HHV8+ than Ac-HHV8- participants.

CONCLUSIONS

In the present study, HHV8 DNA positivity was associated with low insulin secretion in this sub-Saharan African diabetes population.

Ketosis-Prone Diabetes (Flatbush Diabetes): an Emerging Worldwide Clinically Important Entity

PURPOSE OF REVIEW

Ketosis-prone diabetes or Flatbush diabetes has been widely recognized as a clinical entity since 1984. Most of the early clinical studies focused on African American or Afro-Caribbean individuals. It is now being recognized as an important clinical entity in sub-Saharan Africans, Asian and Indian populations, and Hispanic populations. Major questions remain as to its pathogenesis and whether it is a unique type of diabetes or a subset of more severe type 2 diabetes with greater loss of insulin action in target tissues. This review summarizes the main clinical and mechanistic studies to improve the understanding of ketosis-prone (Flatbush) diabetes.

RECENT FINDINGS

Little data are available on the magnitude of KPD in the different susceptible populations. It is relatively common in black populations. KPD is defined as a syndrome in which diabetes commences with ketoacidosis in individuals who are GAD and anti-islet cell antibody negative and have no known precipitating causes. The patients present during middle age, are overweight or mildly obese, and in many reports are more likely to be male. After intensive initial insulin therapy, many patients become insulin independent and can be well controlled on diet alone or diet plus oral medications. The clinical course of KPD is like that of patients with type 2 diabetes rather than that of type 1 diabetes. Little differences are found in the clinical characteristics and clinical outcomes between patients presenting with KPD and those presenting with severe hyperglycemia with no ketoacidosis. The mechanisms responsible for the development of ketosis-prone diabetes as well its remission remain unknown.

Sex differences in metabolism and cardiometabolic disorders

PURPOSE OF REVIEW

Sex differences are pervasive in metabolic and cardiovascular traits, yet they have often been ignored in human and animal model research. Sex differences can arise from reversible hormonal effects, from irreversible organizational (developmental) processes, and from gene expression differences from the X and Y chromosomes. We briefly review our current understanding of the impact of these factors in metabolic traits and disorders, with an emphasis on the recent literature.

RECENT FINDINGS

Novel sex differences continue to be identified for metabolic and cardiovascular traits. For example, it is now clear that gut microbiota tend to differ between men and women, with potentially large implications for disease susceptibility. Also, tissue-specific gene regulation differs between men and women, contributing to differential metabolism. These new insights will open up personalized therapeutic avenues for cardiometabolic diseases.

SUMMARY

Sex differences in body fat distribution, glucose homeostasis, insulin signaling, ectopic fat accumulation, and lipid metabolism during normal growth and in response to hormonal or nutritional imbalance are mediated partly through sex hormones and the sex chromosome complement. Most of these differences are mediated in a tissue-specific manner. Important future goals are to better understand the interactions between genetic variation and sex differences, and to bring an understanding of sex differences into clinical practice.

Sex differences underlying pancreatic islet biology and its dysfunction

Background

The sex of an individual affects glucose homeostasis and the pathophysiology, incidence, and prevalence of diabetes as well as the response to therapy.

Scope of the review

This review focuses on clinical and experimental sex differences in islet cell biology and dysfunction during development and in adulthood in human and animal models. We discuss sex differences in β-cell and α-cell function, heterogeneity, and dysfunction. We cover sex differences in communication between gonads and islets and islet-cell immune interactions. Finally, we discuss sex differences in β-cell programming by nutrition and other environmental factors during pregnancy.

Major conclusions

Important sex differences exist in islet cell function and susceptibility to failure. These differences represent sex-related biological factors that can be harnessed for gender-based prevention of and therapy for diabetes.

Diabetic Ketoacidosis Post Bariatric Surgery

In patients with type 2 diabetes, bariatric surgery can lead to significant improvements in glycemic control and diabetes remission. We present a case of a Hispanic female with type 2 diabetes phenotype who underwent bariatric surgery and post-operatively stopped her insulin therapy due to multiple reasons, including decreased oral intake and concern for hypoglycemia. Ultimately, she developed diabetic ketoacidosis. She does not fit into the classical type 2 diabetes or type 1 diabetes definition but into the heterogeneous subgroup of diabetes called ketosis-prone diabetes.

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.

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.

Gender differences in glucose homeostasis and diabetes

Some aspects of glucose homeostasis are regulated differently in males and females. This review discusses the most fundamental gender differences in glucose homeostasis and diabetes. These include the prevalence of impaired fasting glucose and impaired glucose tolerance, the prevalence and incidence of type 2 and type 1 diabetes, and the sex-specific effects of testosterone and estrogen deficiency and excess. These gender-specific differences in glucose homeostasis represent a source of factors that should be studied to develop gender-based therapeutic avenues for diabetes.

Incidence of diabetic ketoacidosis among patients with type 2 diabetes mellitus treated with SGLT2 inhibitors and other antihyperglycemic agents

AIMS

To estimate and compare incidence of diabetes ketoacidosis (DKA) among patients with type 2 diabetes who are newly treated with SGLT2 inhibitors (SGLT2i) versus non-SGLT2i antihyperglycemic agents (AHAs) in actual clinical practice.

METHODS

A new-user cohort study design using a large insurance claims database in the US. DKA incidence was compared between new users of SGLT2i and new users of non-SGLT2i AHAs pair-matched on exposure propensity scores (EPS) using Cox regression models.

RESULTS

Overall, crude incidence rates (95% CI) per 1000 patient-years for DKA were 1.69 (1.22-2.30) and 1.83 (1.58-2.10) among new users of SGLT2i (n=34,442) and non-SGLT2i AHAs (n=126,703). These rates more than doubled among patients with prior insulin prescriptions but decreased by more than half in analyses that excluded potential autoimmune diabetes (PAD). The hazard ratio (95% CI) for DKA comparing new users of SGLT2i to new users of non-SGLT2i AHAs was 1.91 (0.94-4.11) (p=0.09) among the 30,196 EPS-matched pairs overall, and 1.13 (0.43-3.00) (p=0.81) among the 27,515 EPS-matched pairs that excluded PAD.

CONCLUSIONS

This was the first observational study that compared DKA risk between new users of SGLT2i and non-SGLT2i AHAs among patients with type 2 diabetes, and overall no statistically significant difference was detected.

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.

Primary Care Endocrinology in the Adult Woman

Diabetes mellitus, thyroid disorders, and osteoporosis are endocrine conditions affecting a significant proportion of women presenting to the obstetrician-gynecologist. Obstetrician-gynecologists are often the first health-care providers that young women see in adulthood, and thus, have a critical opportunity to identify women at risk for gestational and overt diabetes and manage the condition in those who have developed it. The obstetrician-gynecologist should be aware of the appropriate therapeutic options and treatment goals (eg, hemoglobin A1c) for women with diabetes. Thyroid disorders often present with menstrual irregularities or infertility, can affect pregnancy outcomes, and contribute to cardiovascular and bone disorders as women age. Finally, osteoporosis and low bone mineral density affect a substantial proportion of older women and some younger women with risk factors for secondary osteoporosis. The morbidity and mortality of osteoporotic fractures is substantial. There are many lifestyle interventions and therapeutic options available for these conditions, and the gynecologist plays a key role in optimizing risk factor assessment, screening, and providing treatment when appropriate.

Ketosis-prone atypical diabetes in Cameroonian people with hyperglycaemic crisis: frequency, clinical and metabolic phenotypes

AIM

It is unclear whether ketosis-prone diabetes is a specific type or a subtype of Type 2 diabetes. We aimed to describe the clinical and metabolic features of ketosis-prone diabetes in a sub-Saharan population.

METHODS

We consecutively enrolled and characterized 173 people with non-autoimmune diabetes admitted for hyperglycaemic crisis at the Yaoundé Central Hospital, Cameroon. Blood samples were collected for fasting glucose, HbA_1c , lipid profile and C-peptide assays with insulin resistance and secretion estimation by homeostasis model assessment. People were classified as having Type 2 diabetes (n = 124) or ketosis-prone diabetes (n = 49). Ketosis-prone diabetes was sub-classified as new-onset ketotic phase (n = 34) or non-ketotic phase (n = 15).

RESULTS

Ketosis-prone diabetes was found in 28.3% of the hyperglycaemic crises. Age at diabetes diagnosis was comparable in Type 2 and ketosis-prone diabetes [48 ± 14 vs 47 ± 11 years; P = 0.13] with a similar sex distribution. Overall BMI was 27.7 ± 13.4 kg/m² and was ≥ 25 kg/m² in 55.8% of those taking part, however, 73.5% of those with ketosis-prone diabetes reported weight loss of > 5% at diagnosis. Blood pressure and lipid profile were comparable in both types. Ketosis-prone diabetes in the ketotic phase was characterized by lower insulin secretion and higher serum triglycerides compared with non-ketotic ketosis prone and Type 2 diabetes. Type 2 and ketosis prone diabetes in the non-ketotic phase were comparable in terms of lipid profile, blood pressure, waist-to-hip ratio, BMI and fat mass, insulin secretion and insulin resistance indices.

CONCLUSIONS

Ketosis-prone diabetes is likely to be a subtype of Type 2 diabetes with the potential to develop acute insulinopenic episodes.

Diabetic ketoacidosis: a challenging diabetes phenotype

SUMMARY

We describe three patients presenting with diabetic ketoacidosis secondary to ketosis prone type 2, rather than type 1 diabetes. All patients were treated according to a standard DKA protocol, but were subsequently able to come off insulin therapy while maintaining good glycaemic control. Ketosis-prone type 2 diabetes (KPD) presenting with DKA has not been described previously in Irish patients. The absence of islet autoimmunity and evidence of endogenous beta cell function after resolution of DKA are well-established markers of KPD, but are not readily available in the acute setting. Although not emphasised in any current guidelines, we have found that a strong family history of type 2 diabetes and the presence of cutaneous markers of insulin resistance are strongly suggestive of KPD. These could be emphasised in future clinical practice guidelines.

LEARNING POINTS

Even in white patients, DKA is not synonymous with type 1 diabetes and autoimmune beta cell failure. KPD needs to be considered in all patients presenting with DKA, even though it will not influence their initial treatment.Aside from markers of endogenous beta cell function and islet autoimmunity, which in any case are unlikely to be immediately available to clinicians, consideration of family history of type 2 diabetes and cutaneous markers of insulin resistance might help to identify those with KPD and are more readily apparent in the acute setting, though not emphasised in guidelines.Consideration of KPD should never alter the management of the acute severe metabolic derangement of DKA, and phasing out of insulin therapy requires frequent attendance and meticulous and cautious surveillance by a team of experienced diabetes care providers.

Epidemiology of Gender Differences in Diabetes and Obesity

Some aspects of glucose homeostasis and energy balance are regulated differently in males and females. This review discusses the most fundamental gender differences in diabetes and obesity, including the prevalence of impaired fasting glucose and impaired glucose tolerance, the prevalence and incidence of type 2 and type 1 diabetes, as well as the prevalence of metabolic syndrome and obesity. These gender-specific differences in glucose homeostasis and energy balance represent a source of factors that should be studied to develop gender-based therapeutic avenues for 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.

Obesity and diabetes mellitus association in rural community of Katana, South Kivu, in Eastern Democratic Republic of Congo: Bukavu Observ Cohort Study Results

BACKGROUND

Factual data exploring the relationship between obesity and diabetes mellitus prevalence from rural areas of sub-Saharan Africa remain scattered and are unreliable. To address this scarceness, this work reports population study data describing the relationship between the obesity and the diabetes mellitus in the general population of the rural area of Katana (South Kivu in the Democratic Republic of the Congo).

METHODS

A cohort of three thousand, nine hundred, and sixty-two (3962) adults (>15 years old) were followed between 2012 and 2015 (or 4105 person-years during the observation period), and data were collected using the locally adjusted World Health Organization's (WHO) STEPwise approach to Surveillance (STEPS) methodology. The hazard ratio for progression of obesity was calculated. The association between diabetes mellitus and obesity was analyzed with logistic regression.

RESULTS

The diabetes mellitus prevalence was 2.8 % versus 3.5 % for obese participants and 7.2 % for those with metabolic syndrome, respectively. Within the diabetes group, 26.9 % had above-normal waist circumference and only 9.8 % were obese. During the median follow-up period of 2 years, the incidence of obesity was 535/100,000 person-years. During the follow-up, the prevalence of abdominal obesity significantly increased by 23 % (p <0.0001), whereas the increased prevalence of general obesity (7.8 %) was not significant (p = 0.53). Finally, diabetes mellitus was independently associated with age, waist circumference, and blood pressure but not body mass index.

CONCLUSION

This study confirms an association between diabetes mellitus and abdominal obesity but not with general obesity. On the other hand, the rapid increase in abdominal obesity prevalence in this rural area population within the follow-up period calls for the urgent promoting of preventive lifestyle measures.

Randomized Controlled Study of Metformin and Sitagliptin on Long-term Normoglycemia Remission in African American Patients With Hyperglycemic Crises

OBJECTIVE

After intensive insulin treatment, many obese African American patients with new-onset diabetic ketoacidosis (DKA) and severe hyperglycemia are able to achieve near-normoglycemia remission. The optimal treatment to prevent hyperglycemic relapses after remission is not known.

RESEARCH DESIGN AND METHODS

This prospective, 4-year, placebo-controlled study randomly assigned 48 African American subjects with DKA and severe hyperglycemia to metformin 1,000 mg daily (n = 17), sitagliptin 100 mg daily (n = 16), or placebo (n = 15) after normoglycemia remission. Hyperglycemic relapse was defined as fasting glucose >130 mg/dL (7.2 mmol/L) and HbA_1c >7.0% (53 mmol/mol). Oral glucose tolerance tests were conducted at randomization and at 3 months and then every 6 months for a median of 331 days. Oral minimal model and incremental area under the curve for insulin (AUCi) were used to calculate insulin sensitivity (Si) and β-cell function, respectively. Disposition index (DI) was calculated as a product of Si and incremental AUCi.

RESULTS

Relapse-free survival was higher in sitagliptin and metformin (P = 0.015) compared with placebo, and mean time to relapse was significantly prolonged in the metformin and sitagliptin groups compared with the placebo group (480 vs. 305 days, P = 0.004). The probability of relapse was significantly lower for metformin (hazard ratio 0.28 [95% CI 0.10-0.81]) and sitagliptin (0.31 [0.10-0.98]) than for placebo. Subjects who remained in remission had a higher DI (P = 0.02) and incremental AUCi (P < 0.001) than those with hyperglycemia relapse without significant changes in Si.

CONCLUSIONS

This study shows that near-normoglycemia remission was similarly prolonged by treatment with sitagliptin and metformin. The prolongation of remission was due to improvement in β-cell function.

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.

Sex differences between APPswePS1dE9 mice in A-beta accumulation and pancreatic islet function during the development of Alzheimer’s disease

The pathogenesis of Alzheimer’s disease (AD), a type of neurodegenerative disease characterized by learning and memory impairment, is often associated with pathological features, such as amyloid-beta (Aβ) accumulation and insulin resistance. The transgenic mouse, APPswePS1dE9 (APP/PS1), is one of the most commonly used animal models in pathogenesis studies of AD. The purpose of this study is to investigate the sex differences between APP/PS1 mice in the pathogenesis of AD. The impairment of glucose and insulin tolerance was found to develop earlier in male APP/PS1 mice than in females. Plasma insulin levels were significantly decreased in male APP/PS1 mice, while total cholesterol levels in male APP/PS1 mice were higher than those in females. Triglyceride levels in male mice in both the wild-type (WT) and APP/PS1 groups were higher than in their female littermates. Soluble and insoluble Aβ levels in female APP/PS1 mouse brains were higher than those in males. And the learning and memorizing abilities of female APP/PS1 mice were poorer than those of males. Our results concluded that there were sex differences in Aβ formation, pancreatic islet function and insulin sensitivity between male and female APP/PS1 mice during the pathogenesis of AD.

Relationship between HHV8 infection markers and insulin sensitivity in ketosis-prone diabetes

BACKGROUND AND OBJECTIVES

Peripheral tissue resistance to insulin action is a characteristic of type 2 diabetes mellitus (T2DM). It has also been reported that some chronic viral infections can contribute to insulin resistance. Human herpesvirus (HHV)-8 infection has been detected in T2DM patients in previous studies. Our study investigated whether the presence of the virus is associated with insulin resistance in patients with ketosis-prone type 2 diabetes (KPD), as reported with other viruses.

RESEARCH DESIGN AND METHODS

A total of 11 insulin-free KPD patients positive (+) and seven patients who were negative (-) for HHV-8 infection were recruited; the latter had KPD that was well controlled (HbA_1c=6.2±0.7%). A two-step euglycaemic-hyperinsulinaemic clamp test coupled with deuterated [6,6-2H2]glucose was used to assess insulin sensitivity, non-esterified fatty acid (NEFA) suppression and endogenous glucose production.

RESULTS

In KPD patients, whether HHV-8+ or HHV-8-, there were no differences in NEFA release, endogenous glucose production or insulin sensitivity (M value).

CONCLUSION

Asymptomatic HHV-8 infection does not appear to be associated with decreased insulin sensitivity in diabetic patients. These results should now be confirmed in a larger sample population.

Impact and characteristics of the non-Caucasian population in hospital admissions for diabetes onset during 2003-2010

AIMS

To assess the prevalence of non-Caucasian patients in hospital admissions for onset of symptomatic diabetes mellitus during the 2003-2010 period, and to analyze the characteristics differentiating them from the Caucasian population at diagnosis and 2 years later.

MATERIAL AND METHODS

A retrospective, observational study.

INCLUSION CRITERIA

Patients aged 18-40 years admitted for de novo symptomatic diabetes from January 2003 to October 2010. Prevalence of patients of non-Caucasian origin was analyzed, and clinical, biochemical, immunological, and beta-cell function of both populations were compared at diagnosis and 2 years later.

RESULTS

Nineteen percent of patients admitted to hospital for de novo symptomatic diabetes were non-Caucasian, with a progressive increase in recent years. Non-Caucasian patients had milder decompensation (3.0% had ketoacidosis, as compared to 15.2% in the Caucasian group, P<.05), lower presence of autoimmunity (27.2 vs. 73.1%, P<.01) and higher stimulated C-peptide levels (0.70±0.56 vs. 0.42±0.39 nmol/l, P<.05), mainly because of the subgroup with negative autoimmunity (0.82 vs. 0.25). Two years after diagnosis, less non-Caucasian patients were on intensified treatment (39.1 vs. 93.8%).

CONCLUSIONS

Non-Caucasian patients had a lower prevalence of autoimmunity, better beta-cell function at diagnosis, particularly due to the subgroup with negative autoimmunity, and less need for intensive treatment 2 years after diagnosis, features which are more characteristic of type 2 diabetes mellitus.

The evolution of diabetic ketoacidosis: An update of its etiology, pathogenesis and management

The prognosis of diabetic ketoacidosis has undergone incredibly remarkable evolution since the discovery of insulin nearly a century ago. The incidence and economic burden of diabetic ketoacidosis have continued to rise but its mortality has decreased to less than 1% in good centers. Improved outcome is attributable to a better understanding of the pathophysiology of the disease and widespread application of treatment guidelines. In this review, we present the changes that have occurred over the years, highlighting the evidence behind the recommendations that have improved outcome. We begin with a discussion of the precipitants and pathogenesis of DKA as a prelude to understanding the rationale for the recommendations. A brief review of ketosis-prone type 2 diabetes, an update relating to the diagnosis of DKA and a future perspective are also provided.

THE CLINICAL AND METABOLIC CHARACTERISTICS OF YOUNG-ONSET KETOSIS-PRONE TYPE 2 DIABETES IN CHINA

OBJECTIVE

To investigate the prevalence and clinical characteristics of ketosis-prone type 2 diabetes (KPD) in Chinese patients with young-onset diabetes.

METHODS

A total of 238 young diabetic patients were recruited from our inpatient department from January 1, 2012, to December 28, 2014. KPD was defined as diabetes without precipitating illness and with the presence of ketosis or diabetic ketoacidosis in the absence of autoantibodies at the time of diagnosis. We reviewed the clinical characteristics and disease progression of this group of patients.

RESULTS

Eighteen patients fulfilled the criteria for KPD, and the prevalence of patients with KPD was 7.6%. The mean (SD) age of the KPD group at the time of diagnosis of diabetes was 27.6 (4.85) years, and these patients were predominantly male (male to female ratio, 8:1) and had a high proportion of obesity and new-onset diabetes and a strong family history of diabetes. β-Cell function in the KPD group was intermediate between type 1 and type 2 diabetes. Patients with KPD had the highest levels of glycated hemoglobin, triglycerides, total cholesterol, and free fatty acids and the lowest levels of high-density lipoprotein. After 3 to 12 months of follow-up, 17 of 18 patients with KPD (94.4%) were able to discontinue insulin therapy, and 11 patients (61.1%) were managed with diet or exercise alone.

CONCLUSION

KPD patients accounted for 7.6% of the diabetic patients requiring admission to a large urban hospital in China, with an age of onset of diabetes of ≤35 years. These patients are more likely to be male, have abnormal lipid metabolism, and have more reversible β-cell dysfunction.

Sex differences in metabolic homeostasis, diabetes, and obesity

There are fundamental aspects of the control of metabolic homeostasis that are regulated differently in males and females. This sex asymmetry represents an evolutionary paradigm for females to resist the loss of energy stores. This perspective discusses the most fundamental sex differences in metabolic homeostasis, diabetes, and obesity. Together, the role of genetic sex, the programming effect of testosterone in the prenatal period in males, and the activational role of sex hormones at puberty produce two different biological systems in males and females that need to be studied separately. These sex-specific differences in energy homeostasis and metabolic dysfunction represent an untested source of factors that can be harnessed to develop relevant sex-based therapeutic avenues for diabetes, metabolic syndrome, and obesity.

Hyperglycaemia per se does not affect erythrocyte glucose-6-phosphate dehydrogenase activity in ketosis-prone diabetes

AIM

Previously, we described patients with ketosis-prone type 2 diabetes (KPD) and glucose-6-phosphate dehydrogenase (G6PD) deficiency, but no mutation of the G6PD gene. Our present study used two complementary approaches to test whether hyperglycaemia might inhibit G6PD activity: (1) effect of acute hyperglycaemia induced by glucose ramping; and (2) effect of chronic hyperglycaemia using correlation between G6PD activity and HbA1c levels.

METHODS

In the first substudy, 16 KPD patients were compared with 11 healthy, non-diabetic control subjects of the same geographical background. Erythrocyte G6PD activity and plasma glucose were assessed at baseline and every 40 min during intravenous glucose ramping that allowed maintaining hyperglycaemia for more than 3h. In the second substudy, erythrocyte G6PD activity and HbA1c levels were evaluated in 108 consecutive African patients with either type 2 diabetes or KPD, and a potential correlation sought between the two variables.

RESULTS

The maximum plasma glucose level after 200 min of glucose perfusion was 20.9±3.7 mmol/L for patients and 10.7±2.3mmol/L for controls. There was no difference between baseline and repeated G6PD activity levels during acute hyperglycaemia in either KPD patients (P=0.94) or controls (P=0.57), nor was there any significant correlation between residual erythrocyte G6PD activity and HbA1c levels (r=-0.085, P=0.38).

CONCLUSION

Neither acute nor chronic hyperglycaemia affects erythrocyte G6PD activity. Thus, hyperglycaemia alone does not explain cases of G6PD deficiency in the absence of gene mutation as described earlier.

Factors associated with early relapse to insulin dependence in unprovoked A-β+ ketosis-prone diabetes

OBJECTIVE

Unprovoked "A-β+" Ketosis-Prone Diabetes (KPD), a unique diabetic syndrome of adult-onset, obesity and proneness to ketoacidosis, is associated with rapid recovery of β cell function and insulin-independence. Whereas most patients experience prolonged remission, a subset relapses early to insulin dependence. We sought to define factors associated with early relapse.

METHODS

We utilized a prospective, longitudinal database to analyze 50 unprovoked A-β+ KPD patients with >2 measurements of β cell function and glycemia following baseline assessment.

RESULTS

19 patients (38%) relapsed to insulin dependence <1 year after the index DKA episode, while 31 (62%) remained insulin-independent for >1 year (median 4.2 years). Younger age at baseline (OR=0.947, P=0.033), and lower HOMA2-%β (OR=0.982, P=0.001), lower HOMA2-IR (OR=0.582, P=0.046) and higher HbA1c at 1 year (OR=1.71, P=0.002) were associated with early relapse. A multivariate model with these variables and the interaction of HOMA2-%β and HbA1c at 1 year provided a good fit (P<0.05).

CONCLUSIONS

Relapse to insulin dependence in unprovoked A-β+ KPD patients is associated with younger age and, after 1 year, lack of robust increase in β cell functional reserve, and suboptimal glycemic control. Measurements of these parameters 1 year after the index DKA episode can be used to assess the need for insulin therapy.

Racial Disparities in the Pathogenesis of Type 2 Diabetes and its Subtypes in the African Diaspora: A New Paradigm

The global epidemic of diabetes has extended to the developing countries including Sub-Sahara Africa. In this context, blacks with type 2 diabetes in the African Diaspora continue to manifest 1.5-2 times higher prevalent rates than in their white counterparts. Previous studies have demonstrated that blacks with and without type 2 diabetes have alterations in hepatic and peripheral insulin sensitivity, beta-cell function, and hepatic insulin clearance as well as hepatic glucose dysregulation when compared to whites. In addition, non-diabetic blacks in the African Diaspora manifest multiple metabolic mediators that predict type 2 diabetes and its subtypes. These pathogenic modifiers include differences in subclinical inflammation, oxidative stress burden, and adipocytokines in blacks in the African Diaspora prior to clinical diagnosis. Consequently, blacks in the African Diaspora manifest subtypes of type 2 diabetes, including ketosis-prone diabetes and J type diabetes. Given the diversity of type 2 diabetes in blacks in the African Diaspora, we hypothesize that blacks manifest multiple early pathogenic defects prior to the diagnosis of type 2 diabetes and its subtypes. These metabolic alterations have strong genetic component, which appears to play pivotal and primary role in the pathogenesis of type 2 diabetes and its subtypes in blacks in the African Diaspora. However, environmental factors must also be considered as major contributors to the higher prevalence of type 2 diabetes and its subtypes in blacks in the African Diaspora. These multiple alterations should be targets for early prevention of type 2 diabetes in blacks in the African Diaspora.

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.

Changes in circulating adiponectin, leptin, glucose and C-peptide in patients with ketosis-prone diabetes

AIMS

To evaluate circulating adipokines in people with ketosis-prone diabetes, a heterogeneous disorder characterized by unprovoked ketoacidosis in people with previously unrecognized diabetes.

METHODS

Patients presenting with ketoacidosis with no previous diabetes diagnosis were compared with patients with previously established Type 1 diabetes. Baseline assessments of autoimmune status (A+/A-), and β-cell function (B+/B-), as well as leptin and adiponectin levels during a standardized mixed-meal tolerance test of 120 min, were performed. In all, 20 patients with heterogeneous ketosis-prone diabetes and 12 patients with Type 1 diabetes were evaluated at baseline, 12 and 24 months.

RESULTS

At baseline, during a mixed-meal tolerance test, glucose and adiponectin concentrations were lower in patients with ketosis-prone diabetes than in those with Type 1 diabetes (P = 0.0023 and P < 0.0001, respectively), whereas C-peptide concentrations were higher, with no significant difference in leptin concentrations. Within 12 months, 11 patients with ketosis-prone diabetes (all A-/B+) were discontinued from insulin treatment (ketosis-prone diabetes - insulin group), while nine patients (four A-B-, four A+B- and one A-B+) were maintained on insulin (ketosis-prone diabetes + insulin group). Fasting C-peptide levels increased significantly over 24 months in the ketosis-prone diabetes - insulin group (P = 0.01), while HbA1c levels decreased (P < 0.0001). Overall, the ketosis-prone diabetes - insulin group had a higher BMI (P = 0.018), yet a lower fasting glucose concentration (P = 0.003) compared with the ketosis-prone diabetes + insulin group. Over 24 months, the mixed-meal tolerance test area-under-the-curve of C-peptide increased in the ketosis-prone diabetes - insulin group, with no change in ketosis-prone diabetes + insulin (P < 0.0001). At 24 months, in spite of the higher BMI in the ketosis-prone diabetes - insulin group, mixed-meal tolerance test glucose and leptin concentrations were significantly lower (P < 0.0001 and P = 0.017, respectively), while adiponectin levels were higher (P = 0.023) compared with the ketosis-prone diabetes + insulin group.

CONCLUSIONS

In spite of the higher BMI in the ketosis-prone diabetes - insulin group, lower leptin and higher adiponectin levels may contribute to improved β-cell function and insulin sensitivity, as evidenced by lower glucose and higher C-peptide levels. This allows insulin therapy to be withdrawn.

Update on diabetes classification

This article highlights the difficulties in creating a definitive classification of diabetes mellitus in the absence of a complete understanding of the pathogenesis of the major forms. This brief review shows the evolving nature of the classification of diabetes mellitus. No classification scheme is ideal, and all have some overlap and inconsistencies. The only diabetes in which it is possible to accurately diagnose by DNA sequencing, monogenic diabetes, remains undiagnosed in more than 90% of the individuals who have diabetes caused by one of the known gene mutations. The point of classification, or taxonomy, of disease, should be to give insight into both pathogenesis and treatment. It remains a source of frustration that all schemes of diabetes mellitus continue to fall short of this goal.

Association of HLA class II markers with autoantibody-negative ketosis-prone atypical diabetes compared to type 2 diabetes in a population of sub-Saharan African patients

AIM

We investigated the association of HLA DRB1 and DQB1 alleles, haplotypes and genotypes with unprovoked antibody-negative ketosis-prone atypical diabetes (A(-) KPD) in comparison to type 2 diabetes (T2D).

METHODS

A(-) KPD and T2D sub-Saharan African patients aged 19-63 years were consecutively recruited. Patients positive for cytoplasmic islet cell, insulin, glutamic acid decarboxylase or islet antigen-2 autoantibodies were excluded. Odds ratios were obtained via logistic regression after considering alleles with a minimum frequency of 5% in the study population. Bonferroni correction was used in the case of multiple comparisons.

RESULTS

Among the 130 participants, 35 (27%) were women and 57 (44%) were A(-) KPD. DRB1 and DQB1 allele frequencies were similar for both A(-) KPD and T2D patients; they did not confer any substantial risk even after considering type 1 diabetes susceptibility and resistance alleles. We found no association between A(-) KPD and the derived DRB1*07-DQB1*02:02 (OR: 0.55 [95%CI: 0.17-1.85], P=0.336); DRB1*11-DQB1*03:01 (OR: 2.42 [95%CI: 0.79-7.42], P=0.123); DRB1*15-DQB1*06:02 (OR: 0.87 [95%CI: 0.39-1.95], P=0.731) and DRB1*03:01-DQB1*02:01 (OR: 1.48 [95%CI: 0.55-3.96], P=0.437) haplotypes. Overall, we did not find any evidence of susceptibility to ketosis associated with DRB1 and DQB1 genotypes (all P>0.05) in A(-) KPD compared to T2D. Similar results were obtained after adjusting the analysis for age and sex.

CONCLUSION

Factors other than DRB1 and DQB1 genotype could explain the propensity to ketosis in A(-) KPD. These results need to be confirmed in a larger population with the perspective of improving the classification and understanding of the pathophysiology of A(-) KPD.