Diabetes information in the Cochrane Library

The accuracy of provider diagnosed diabetes type in youth compared to an etiologic criteria in the SEARCH for Diabetes in Youth Study

BACKGROUND

Although surveillance for diabetes in youth relies on provider-assigned diabetes type from medical records, its accuracy compared to an etiologic definition is unknown.

METHODS

Using the SEARCH for Diabetes in Youth Registry, we evaluated the validity and accuracy of provider-assigned diabetes type abstracted from medical records against etiologic criteria that included the presence of diabetes autoantibodies (DAA) and insulin sensitivity. Youth who were incident for diabetes in 2002-2006, 2008, or 2012 and had complete data on key analysis variables were included (n = 4001, 85% provider diagnosed type 1). The etiologic definition for type 1 diabetes was ≥1 positive DAA titer(s) or negative DAA titers in the presence of insulin sensitivity and for type 2 diabetes was negative DAA titers in the presence of insulin resistance.

RESULTS

Provider diagnosed diabetes type correctly agreed with the etiologic definition of type for 89.9% of cases. Provider diagnosed type 1 diabetes was 96.9% sensitive, 82.8% specific, had a positive predictive value (PPV) of 97.0% and a negative predictive value (NPV) of 82.7%. Provider diagnosed type 2 diabetes was 82.8% sensitive, 96.9% specific, had a PPV and NPV of 82.7% and 97.0%, respectively.

CONCLUSION

Provider diagnosis of diabetes type agreed with etiologic criteria for 90% of the cases. While the sensitivity and PPV were high for youth with type 1 diabetes, the lower sensitivity and PPV for type 2 diabetes highlights the value of DAA testing and assessment of insulin sensitivity status to ensure estimates are not biased by misclassification.

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.

Ketosis-onset diabetes and ketosis-prone diabetes: same or not?

Objective. To compare clinical characteristics, immunological markers, and β -cell functions of 4 subgroups ("A β " classification system) of ketosis-onset diabetes and ketosis prone diabetes patients without known diabetes, presenting with ketosis or diabetic ketoacidosis (DKA) and admitted to our department from March 2011 to December 2011 in China, with 50 healthy persons as control group. Results. β -cell functional reserve was preserved in 63.52% of patients. In almost each subgroup (except A-   β - subgroup of ketosis prone group), male patients were more than female ones. The age of the majority of patients in ketosis prone group was older than that of ketosis-onset group, except A-   β - subgroup of ketosis prone group. The durations from the patient first time ketosis or DKA onset to admitting to the hospital have significant difference, which were much longer for the ketosis prone group except the A+ β + subgroup. BMI has no significant difference among subgroups. FPG of ketosis prone group was lower than that of A-   β + subgroup and A+ β + subgroup in ketosis-onset group. A-   β - subgroup and A+ β + subgroup of ketosis prone group have lower HbA1c than ketosis-onset group. Conclusions. Ketosis-onset diabetes and ketosis prone diabetes do not absolutely have the same clinical characteristics. Each subgroup shows different specialty.

The potential role of glutamate in the current diabetes epidemic

In the present article, we propose the perspective that abnormal glutamate homeostasis might contribute to diabetes pathogenesis. Previous reports and our recent data indicate that chronically high extracellular glutamate levels exert direct and indirect effects that might participate in the progressive loss of β-cells occurring in both T1D and T2D. In addition, abnormal glutamate homeostasis may impact all the three accelerators of the "accelerator hypothesis" and could partially explain the rising frequency of T1D and T2D.

Presence or absence of a known diabetic ketoacidosis precipitant defines distinct syndromes of "A-β+" ketosis-prone diabetes based on long-term β-cell function, human leukocyte antigen class II alleles, and sex predilection

Ketosis-prone diabetes (KPD) is heterogeneous. Longitudinal follow-up revealed that patients with "A-β+" KPD (absent autoantibodies and preserved β-cell function) segregated into 2 subgroups with distinct evolution of β-cell function and glycemic control. Generalized linear analysis demonstrated that the variable that most significantly differentiated them was presence of a clinically evident precipitating event for the index diabetic ketoacidosis (DKA). Hence, we performed a comprehensive analysis of A-β+ KPD patients presenting with "provoked" compared with "unprovoked" DKA. Clinical, biochemical, and β-cell functional characteristics were compared between provoked and unprovoked A-β+ KPD patients followed prospectively for 1 to 8 years. Human leukocyte antigen class II allele frequencies were compared between these 2 groups and population controls. Unprovoked A-β+ KPD patients (n = 83) had greater body mass index, male preponderance, higher frequency of women with oligo-/anovulation, more frequent African American ethnicity, and less frequent family history of diabetes than provoked A-β+ KPD patients (n = 64). The provoked group had higher frequencies of the human leukocyte antigen class II type 1 diabetes mellitus susceptibility alleles DQB1*0302 (than the unprovoked group or population controls) and DRB1*04 (than the unprovoked group), whereas the unprovoked group had a higher frequency of the protective allele DQB1*0602. β-Cell secretory reserve and glycemic control improved progressively in the unprovoked group but declined in the provoked group. The differences persisted in comparisons restricted to patients with new-onset diabetes. "Unprovoked" A-β+ KPD is a distinct syndrome characterized by reversible β-cell dysfunction with male predominance and increased frequency of DQB1*0602, whereas "provoked" A-β+ KPD is characterized by progressive loss of β-cell reserve and increased frequency of DQB1*0302 and DRB1*04. Unprovoked DKA predicts long-term β-cell functional reserve, insulin independence, and glycemic control in KPD.

The accelerator hypothesis: a review of the evidence for insulin resistance as the basis for type I as well as type II diabetes

Although some 40 years have passed since type I diabetes was first defined, its cause remains unknown. The autoimmunity paradigm of immune dysregulation has not offered an explanation for its rising incidence, nor means of preventing it, and there is arguably good reason to consider alternatives. The accelerator hypothesis is a singular, unifying concept that argues that type I and type II diabetes are the same disorder of insulin resistance, set against different genetic backgrounds. The hypothesis does not deny the role of autoimmuniy, only its primacy in the process. It distinguishes type I and type II diabetes only by tempo, the faster tempo reflecting the more susceptible genotype and (inevitably) earlier presentation. Insulin resistance is closely related to the rise in overweight and obesity, a trend that the hypothesis deems central to the rising incidence of all diabetes in the developed and developing world. Rather than overlap between the two types of diabetes, the accelerator hypothesis envisages overlay-each a subset of the general population differing from each other only by genotype. Indeed, it views type I and type II diabetes as a continuum, where the infinitely variable interaction between insulin resistance and genetic response determines the age at which beta-cell loss becomes critical. Adult diabetes is not viewed as an entity, but rather as diabetes presenting in adulthood. Childhood diabetes, similarly, is diabetes presenting in childhood. The increasing incidence of both is primarily the result of lifestyle change and the rise in body weight that has resulted.

A sub-Saharan African perspective of diabetes

Diabetes mellitus is an important and increasing cause of morbidity and mortality in sub-Saharan Africa. Accurate epidemiological studies are often logistically and financially difficult, but processes of rural-urban migration and epidemiological transition are certainly increasing the prevalence of type 2 diabetes. Type 1 disease is relatively rare, although this may be related to high mortality. This diabetic subgroup appears to present at a later age (by about a decade) than in Western countries. Variant forms of diabetes are also described in the continent; notably 'atypical, ketosis-prone' diabetes, and malnutrition-related diabetes mellitus. These types sometimes make the distinction between type 1 and type 2 diabetes difficult. Interestingly, this is also a current experience in the developed world. As more detailed and reliable complication studies emerge, it is increasingly apparent that African diabetes is associated with a high complication burden, which is both difficult to treat and prevent. More optimistically, a number of intervention studies and twinning projects are showing real benefits in varying locations. Future improvements depend on practical and sustainable support, coupled with local acceptance of diabetes as a major threat to the future health and quality of life of sub-Saharan Africans.

Association between body mass index and core components of metabolic syndrome in 1486 patients with type 1 diabetes mellitus in Japan (JDDM 13)

There is no recent study on the prevalence of overweight and obesity in patients with type 1 diabetes mellitus (T1DM) in Japan. Being overweight has a significant effect on the metabolic condition and glycemic control of such patients. In the present cross-sectional study, we investigated the effects of body mass index (BMI) on lipid profile, blood pressure, and glycemic control in patients with T1DM. In total, 1486 patients with T1DM (including 401 patients with early onset T1DM who were <20 years of age at diagnosis) were included. Patients were divided into four groups according to their BMI, and glycosylated hemoglobin (HbA1c), daily insulin dose per kg body weight, lipid profile, and blood pressure were compared between groups. We found that 15.7% of all patients were overweight (BMI >or= 25.0 kg/m(2)) and 2.0% were obese (BMI >or= 30.0 kg/m(2)), compared with 17.5% and 2.0%, respectively, in the early onset T1DM subgroup. Significant changes in lipid profiles and blood pressure were found with increasing BMI in both the entire population and the early onset T1DM subgroup. In the entire study population HbA1c and the body weight-adjusted daily insulin dose were significantly higher in patients with a BMI >or= 23 kg/m(2) compared with those with a BMI<23 kg/m(2); however, this was not the case in the early onset T1DM subgroup. This difference may be due to the relatively small number of patients in that subgroup. In conclusion, the prevalence of overweight and obesity in patients with T1DM was less than that in the normal Japanese population. For patients with T1DM, being overweight was associated with higher blood pressure and dyslipidemia. Furthermore, we cannot exclude an association between being overweight and the need for higher daily doses of insulin.

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.

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.

Type 2 diabetes presenting as diabetic ketoacidosis in adolescence

We report two black adolescent subjects who presented with diabetic ketoacidosis, but who lacked autoimmune markers and demonstrated clinical and biochemical characteristics more typical of Type 2 diabetes, including obesity, acanthosis nigricans, positive family history for Type 2 diabetes, and Type 2 diabetic dyslipidaemia. Subsequent to acute presentation, insulin was discontinued in both subjects and excellent glycaemic control was achieved with metformin therapy alone. Four months following acute presentation, both had adequate C-peptide responses to intravenous glucagon. Type 2 diabetes can present as diabetic ketoacidosis in obese adolescent subjects.

Idiopathic Type 1 diabetes

The purpose of this article is to review the available pathophysiological and clinical studies of patients with idiopathic Type 1 diabetes. Idiopathic Type 1 diabetes is a common form of diabetes most commonly seen in obese African American individuals living in large urban areas. This type of diabetes usually presents with the typical signs and symptoms of Type 1 diabetes such as diabetic ketoacidosis but its subsequent clinical course often resembles Type 2 diabetes. The natural history and pathogenesis of idiopathic Type 1 diabetes is unknown because most of these studies on these patients were done shortly after diagnosis. For the most part, these patients have been treated as if they had Type 2 diabetes with diet and/or oral agents but recent studies suggest that patients have a very variable response to diet and oral agents. They seem to have better long-term glycemic control with the use of insulin therapy. Although the pathogenesis of this disease is unknown, it may be related to lipotoxicity, glucose toxicity or transcription factors involved in fuel metabolism.