Diabetes epidemiology: guiding clinical and public health practice: the Kelly West Award Lecture, 2006

Characterizing the clinical profile and prevalence of people with diabetes attended in the hospital setting by using unstructured healthcare data and natural language processing: the Diabetic@ study

AIMS

This study aimed to evaluate the potential of unstructured electronic health records (EHRs) data, analyzed using natural language processing (NLP) and machine learning (ML), to describe the prevalence and clinical spectrum of diabetes mellitus (DM) in hospitals.

METHODS

A multicenter, retrospective study was conducted using EHRs from eight Spanish hospitals (2013-2018). Unstructured data were extracted using EHRead® (NLP and ML) and SNOMED_CT. Individuals with type 1 or 2 DM (T1DM/T2DM) were identified, and a semi-supervised ML classifier was developed for unregistered types (UrDM). DM prevalence and related complications were analyzed in the final subpopulations (sT1DM/sT2DM).

RESULTS

From 56,181,954 EHRs of 2,582,778 individuals, 638,730 were identified with DM: 75.4 % with UrDM, 21.3 % with T2DM, and 3.3 % with T1DM. The ML model reclassified 93.5 % as T2DM and 6.5 % as T1DM. Over 50 % of relevant variables like anthropometrics, lab values and treatments were missing. The prevalence of sT1DM/sT2DM was 2.6 %/38.4 %. Major comorbidities included hypertension, dyslipidemia, chronic kidney disease (CKD), ischemic heart disease, and chronic heart failure (CHF). CKD and CHF were the most frequent complications for sT1DM/sT2DM at 60 months.

CONCLUSIONS

NLP and ML for profiling DM using EHRs unstructured data are helpful, but additional data and better EHR documentation are crucial.

Osteogenesis of bone marrow mesenchymal stem cell in hyperglycemia

Diabetes mellitus (DM) has been shown to be a clinical risk factor for bone diseases including osteoporosis and fragility. Bone metabolism is a complicated process that requires coordinated differentiation and proliferation of bone marrow mesenchymal stem cells (BMSCs). Owing to the regenerative properties, BMSCs have laid a robust foundation for their clinical application in various diseases. However, mounting evidence indicates that the osteogenic capability of BMSCs is impaired under high glucose conditions, which is responsible for diabetic bone diseases and greatly reduces the therapeutic efficiency of BMSCs. With the rapidly increasing incidence of DM, a better understanding of the impacts of hyperglycemia on BMSCs osteogenesis and the underlying mechanisms is needed. In this review, we aim to summarize the current knowledge of the osteogenesis of BMSCs in hyperglycemia, the underlying mechanisms, and the strategies to rescue the impaired BMSCs osteogenesis.

Recent applications of machine learning and deep learning models in the prediction, diagnosis, and management of diabetes: a comprehensive review

Diabetes as a metabolic illness can be characterized by increased amounts of blood glucose. This abnormal increase can lead to critical detriment to the other organs such as the kidneys, eyes, heart, nerves, and blood vessels. Therefore, its prediction, prognosis, and management are essential to prevent harmful effects and also recommend more useful treatments. For these goals, machine learning algorithms have found considerable attention and have been developed successfully. This review surveys the recently proposed machine learning (ML) and deep learning (DL) models for the objectives mentioned earlier. The reported results disclose that the ML and DL algorithms are promising approaches for controlling blood glucose and diabetes. However, they should be improved and employed in large datasets to affirm their applicability.

Beneficial effects of curcumin in the diabetic rat ovary: a stereological and biochemical study

This study aimed to investigate the effects of curcumin treatment on ovaries at different periods of the diabetes disease. Fifty-six female Wistar albino rats (250-300 g) aged 12 weeks were divided into seven groups. No treatment was applied to the control group. The sham group was given 5 mL/kg of corn oil, and the curcumin group 30 mg/kg curcumin. In the diabetes mellitus (DM) groups, diabetes was induced by a single intraperitoneal dose of 50 mg/kg streptozotocin (STZ). The DM-treated groups received 30 mg/kg curcumin after either 7 days (DC1 group) or 21 days (DC2 group), or simultaneously with STZ injection (DC3 group). Number of follicles in the ovaries was estimated using stereological method. Follicle-stimulating hormone (FSH), luteinizing hormone (LH), and superoxide dismutase (SOD) levels and catalase (CAT) activity were measured in serum specimens. We found that follicle number and volume of corpus luteum, blood vessel, and cortex, gonadosomatic index, and FSH and SOD levels all decreased significantly in diabetic ovaries, while relative weight loss, connective tissue volume, and CAT activity increased (p < 0.01). Curcumin treatment had a protective effect on the number of primordial follicles in the DC2 group and on antral follicle numbers in the DC3 group. Curcumin also exhibited positive effects on CAT activity and SOD levels, blood glucose levels, and corpus luteum, connective tissue, and blood vessel volumes in the DC2 and DC3 groups. Curcumin also ameliorated FSH levels in the DC1 and DC3 groups (p < 0.01). These findings suggest that curcumin exhibits protective effects on ovarian structures and folliculogenesis, especially when used concurrently with the development of diabetes or in later stages of the disease.

Simplified, Low-Cost Method on Glucose Tolerance Testing in High-Risk Group of Diabetes, Explored by Simulation of Diagnosis

Objective: Explore the distribution of basic characteristics of high-risk groups of diabetes; verify the practical significance and diagnostic value of the “three-point method”; layered analysis of glycated hemoglobin and glycated serum albumin, and study its value and significance in the diagnosis of diabetes mellitus, Type II and pre-diabetes mellitus, Type II.Methods: 1304 high-risk individuals with T2D in Shanghai, 529 males and 841 females with an average of (50.5 ± 15.2) years old, were examined by oral glucose tolerance test (OGTT), HbA1c and GA were determined. Process the data by Python and GraphPad; judge the diagnostic value of HbA1C, GA by ROC.Results: (1) The numbers of DM, NGT, HOG, IFG, Mild–IGT and Mid–IGT in the objects were 647, 141, 70, 4, 208 and 234 respectively. In the 43-49 age group with a higher incidence, the proportion of selected high-risk groups is low. (2) The sensitivity and specificity about “three-point method” used to determine NGT is 100% and 90.11%; to determine IGR is 75.11% and 97.32%; to determine HOG is 97.14% and 100%; to determine DM is 94.67% and 100%. (3) According to ROC judgment, it is found that these 2 did not have the function of separate diagnoses, the optimal critical point of HbA1C related to DM status is 5.95%, (P<.01); HbA1C related to IGR status is 5.75% (P<.01); of GA related to DM status is 15.25% (P<.01); GA related to IGR status is 14.95% (P<.01).

Retinal Neurovascular Coupling in Diabetes

Neurovascular coupling, also termed functional hyperemia, is one of the physiological key mechanisms to adjust blood flow in a neural tissue in response to functional activity. In the retina, increased neural activity, such as that induced by visual stimulation, leads to the dilatation of retinal arterioles, which is accompanied by an immediate increase in retinal and optic nerve head blood flow. According to the current scientific view, functional hyperemia ensures the adequate supply of nutrients and metabolites in response to the increased metabolic demand of the neural tissue. Although the molecular mechanisms behind neurovascular coupling are not yet fully elucidated, there is compelling evidence that this regulation is impaired in a wide variety of neurodegenerative and vascular diseases. In particular, it has been shown that the breakdown of the functional hyperemic response is an early event in patients with diabetes. There is compelling evidence that alterations in neurovascular coupling precede visible signs of diabetic retinopathy. Based on these observations, it has been hypothesized that a breakdown of functional hyperemia may contribute to the retinal complications of diabetes such as diabetic retinopathy or macular edema. The present review summarizes the current evidence of impaired neurovascular coupling in patients with diabetes. In this context, the molecular mechanisms of functional hyperemia in health and disease will be covered. Finally, we will also discuss how neurovascular coupling may in future be used to monitor disease progression or risk stratification.

Recurrent cardiovascular events in patients with newly diagnosed acute coronary syndrome: Influence of diabetes and its management with medication

AIMS

The effects of type 2 diabetes mellitus (T2DM) medications on secondary prevention after acute coronary syndrome (ACS) remain unclear. We evaluated recurrent cardiovascular disease (CVD) after primary diagnosis of ACS in T2DM patients.

METHODS

This retrospective cohort study included 569 patients with newly diagnosed ACS from 2007 to 2012. The endpoint was recurrent CVD up to a five-year maximum follow-up until 2016. Kaplan-Meier analysis and Cox proportional hazard regressions were performed to examine the association between T2DM diagnosis, different antidiabetic drugs, and recurrent CVD.

RESULTS

Among 569 patients, 198 had T2DM. The mean follow-up was 1540 (interquartile range, 864-2157) days. Patients with diabetes showed higher risk of recurrent cardiovascular event compared with those without (P = 0.004). Patients with diabetes treated with metformin (65 patients) showed longer event-free survival, compared with those on other antidiabetic medications (P = 0.005). Multivariable analysis confirmed a reduced risk of recurrent CVD associated with metformin (hazard ratio, 0.33; 95% confidence interval, 0.12-0.91), while lower hemoglobin A1c levels on admission were not associated with better CVD outcomes.

CONCLUSIONS

T2DM increases risk of recurrent CVD after first ACS episode regardless of glycemic control on admission, while use of metformin may reduce recurrence.

Evaluation of Several Anthropometric and Metabolic Indices as Correlates of Hyperglycemia in Overweight/Obese Adults

AIM

Rapid and growing rise in obesity and diabetes mellitus, as serious human health-threatening issues, is alarming. The aim of the present study was assessing the accuracy of several obesity indices to predict hyperglycemia in overweight and obese Iranian populations and determining the value of such indices in comparison to the conventional parameters. We also evaluated new latent combined scores in this matter.

PATIENTS AND METHODS

Overall, there were 2088 patients recruited from the weight loss clinic of Sina Hospital, an educational hospital of Tehran University of Medical Sciences for this cross-sectional study. Demographic information, anthropometric indices and biochemical measurements were collected and calculated. The multivariable regression modeling as well as area under the receiver-operating characteristic (ROC) analysis was used. To detect the existence of new combined scores, we used SEM (structural equation modeling) analysis through SmartPLS.

RESULTS

Combined latent scores and WHtR (waist-to-height ratio) gave us a higher area under the curve in predicting hyperglycemia associated with WC (waist circumference) in women, whereas FFMI (fat-free mass index) gave low values. Additionally, BRI (body roundness index) and latent scores had slightly higher AUC values in predicting hyperglycemia in men. According to the age-adjusted odds ratio (OR) in the presence of hyperglycemia, OR was the highest for WHR (waist to hip ratio) in women (OR, 7.74; 95% confidence interval [CI], 1.71-15.13). The association of WHR and hyperglycemia remained significant by adjusting for BMI (body mass index), WC and menopausal status.

CONCLUSION

WHR had the strongest association with hyperglycemia in women with only sufficient discrimination ability. However, neither BSI (body shape index) and BAI (body adiposity index) nor FMI (fat mass index) and FFMI were superior to BMI (body mass index), WC or WHtR in predicting hyperglycemia. It was revealed that BRI and combined scores had a more predictive power compared to the BSI, BAI, FMI and FFMI, simplifying hyperglycemia evaluation.

Rethinking the accuracy of 75g glucose used in the oral glucose tolerance test in the diagnosis and management of diabetes

AIMS

We investigated the specificity of the 75g oral glucose tolerance test (OGTT) and the clinical usefulness of the 2h post loading glucose (2h PLG) value in the clinical care of diabetes patients.

METHODS

The 75g OGTT data of 1755 subjects were analyzed. The relationships and degrees of consistency among 2h PLG, fasting plasma glucose (FPG), and HbA1c values were assessed. We also investigated the degree of contribution of 2h PLG in the prescription of glucose-lowering agents and in the pitfall group for use of 75g OGTT.

RESULTS

Among 595 subjects with normal FPG, only 329 (55.3%) showed normal 2h PLG level, and 66 (11.1%) patients could be considered as having diabetes. Among 454 diabetes patients (based on FPG and HbA1c), 409(90.1%) showed 2h PLG values in the range of diabetes, 45 (9.9%) subjects did not exhibit diabetes. Pitfall group who used 75g OGTT for diagnosis diabetes (lower 2h PLG value compared to fasting and upper 2h PLG value compared to fasting) showed differences in body weight and height.

CONCLUSIONS

Based on OGTT results, around 10% patients cannot be diagnosed with diabetes based solely on the 2h PLG value. Further studies on differences in glucose loading according to body weight, individual life pattern, and calorie requirement are needed for improvement of the specificity of the OGTT in the clinical management of diabetes.

Diabetic Microagiopathy of Oral Mucosa Depends on Disease Duration and Therapy

Background

Diabetes mellitus is a chronic degenerative systemic disease whose prevalence is increasing. This paper aims to evaluate the effects of diabetic microangiopathy, depending on its duration and the type of treatment administered, by using polarized light videocapillaroscopy of the oral mucosa.

Material/Methods

We enrolled 120 subjects: 60 healthy subjects and 60 patients with diabetes mellitus. In turn, patients were divided into 3 subgroups according to the type of diabetes, the duration of the disease, and the type of treatment administered. A videocapillaroscopic examination of the oral mucosa was carried out on the diabetic and healthy subjects.

Results

Changes in microcirculation were detected in diabetic patients: at the level of the labial, buccal, and lingual mucosa, the density of the loops is on average reduced; there is an increase in the length and the total diameter of the loops, while the average density of the periodontal capillaries is much higher. The most significant changes were noted in patients who had had type 1 diabetes for more than 10 years and had received insulin therapy.

Conclusions

This study, performed using polarized light videocapillaroscopy, which for the first time was used to analyze the capillaries of the oral mucosa in patients with diabetes, confirms the presence of changes that are instrumentally “objectifiable” and “quantifiable” through the videocapillaroscopic technique. Videocapillaroscopy can be a reliable method in the study and monitoring of complications in patients with type 1 and 2 diabetes mellitus.

Obesity, metabolic syndrome and diabetic retinopathy: Beyond hyperglycemia

Diabetic retinopathy (DR) is the most feared ocular manifestation of diabetes. DR is characterized by progressive retinal damage that may eventually result in blindness. Clinically, this blindness is caused by progressive damage to the retinal microvasculature, which leads to ischemia, retinal swelling, and neovascularization. Retinopathy is associated with both type 1 and type 2 diabetes, with DR being the leading cause of new onset blindness in United States adults. Despite this strong association with diabetes, it must be noted that the development of retinopathy lesions is multifactorial and may occur in individuals without an established history of diabetes. Metabolic syndrome is a multifactorial condition of central obesity, hypertriglyceridemia, dyslipidemia, hypertension, fasting hyperglycemia, and insulin resistance. Although several studies examined the individual components observed in the metabolic syndrome in relation to the development of DR, there is conflicting data as to the association of the metabolic syndrome with the development of retinopathy lesions in non-diabetic subjects. This review will summarize the current literature on the evidence of the metabolic syndrome on retinopathy in subjects with and without an established history of diabetes. This review will also discuss some of the mechanisms through which metabolic syndrome can contribute to the development of retinopathy.

Serum 1,5-anhydroglucitol level as a screening tool for diabetes mellitus in a community-based population at high risk of diabetes

AIMS

Early diagnosis of diabetes yields significant clinical benefits; however, currently available diagnostic tools for community-based population are limited. This study aimed to assess the value of serum 1,5-anhydroglucitol (1,5-AG) for the diagnosis and screening of diabetes mellitus in a community-based population at high risk of diabetes.

METHODS

In this diagnostic test, 1170 participants underwent a 75-g oral glucose tolerance test. Venous blood samples were collected for fasting blood glucose (FBG), 2-h postprandial blood glucose (PBG), and glycosylated hemoglobin A1c (HbA1c) measurements. Serum 1,5-AG levels were detected by the GlycoMark assay, and a receiver operating characteristic (ROC) curve was generated to assess their diagnostic value for diabetes.

RESULTS

A total of 298 adults were diagnosed with diabetes, indicating a prevalence of 25.47%. Partial Pearson correlation analysis adjusted for age and body mass index showed that serum 1,5-AG level was negatively correlated with FBG, PBG, and HbA1c (all P < 0.01). Areas under the curves (AUCs) for serum 1,5-AG, FBG, PBG, and HbA1c in identifying diabetes were 0.920, 0.874, 0.933, and 0.887, respectively. According to the ROC curve, the optimal cutoff value of serum 1,5-AG for diagnosing diabetes was 11.18 μg/ml, which yielded a sensitivity of 92.6% and a specificity of 82.3%, respectively. Comparisons between 1,5-AG and HbA1c showed that both the AUC and sensitivity of 1,5-AG were higher than those of HbA1c (both P < 0.01).

CONCLUSIONS

Serum 1,5-AG is a simple and effective marker with high sensitivity and specificity for identifying diabetes in populations at high risk of diabetes.

Diabetes, pre-diabetes and their risk factors in Malta: a study profile of national cross-sectional prevalence study

Background

Type 2 diabetes mellitus constitutes a global epidemic and a major burden on health care systems across the world. Prevention of this disease is essential, and the development of effective prevention strategies requires validated information on the disease burden and the risk factors. Embarking on a nationally representative cross-sectional study is challenging and costly. Few countries undertake this process regularly, if at all.

Method

This paper sets out the evidence-based protocol of a recent cross-sectional study that was conducted in Malta. Data collection took place from November 2014 to January 2016.

Results

This study presents up-to-date national data on diabetes and its risk factors (such as obesity, smoking, physical activity and alcohol intake) that will soon be publicly available.

Conclusion

This protocol was compiled so that the study can be replicated in other countries. The protocol contains step-by-step descriptions of the study design, including details on the population sampling, the permissions required and the validated measurement tools used.

Antiresorptive therapy and newly diagnosed diabetes in women: a historical cohort study

AIMS

Undercarboxylated osteocalcin (ucOC) promotes increased insulin sensitivity and increased secretion. Since antiresorptive therapy (AT) decreases ucOC levels, AT could increase the risk of diabetes and this would have serious clinical ramifications. We sought to test this hypothesis by examining the association between new use of AT and newly-diagnosed diabetes.

METHODS

Using a bone mineral density (BMD) registry for Manitoba, Canada, we identified 33 640 women aged ≥50 years without diabetes at their first BMD test for 1998-2013. We linked these women to a province-wide retail pharmacy database to identify new AT exposure each year for up to 5 years after a BMD test. Time-dependent analysis was used to test the independent association between new use of AT and newly diagnosed diabetes.

RESULTS

This cohort had a mean age of 65 years, a mean body mass index of 26.8 kg/m(2) , and 12% were receiving glucocorticoid and 13% hormone replacement therapy at BMD test. In the first year after BMD test, 29% of women started AT (bisphosphonates, 92%). Over a mean 4.2 years of follow-up, 3.7% new AT users and 4.2% non-users had diabetes (adjusted hazard ratio 1.01, 95% confidence interval 0.87-1.16). Sensitivity analyses using AT dose-response gradients also found no significant associations with diabetes.

CONCLUSIONS

Despite the plausible biological mechanisms related to ucOC, new use of AT was not a risk factor for diabetes in this cohort. The clinical implications of these findings are reassuring, as AT is widely prescribed for treating osteoporosis in older women who are also at high risk of developing diabetes.

Type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is an expanding global health problem, closely linked to the epidemic of obesity. Individuals with T2DM are at high risk for both microvascular complications (including retinopathy, nephropathy and neuropathy) and macrovascular complications (such as cardiovascular comorbidities), owing to hyperglycaemia and individual components of the insulin resistance (metabolic) syndrome. Environmental factors (for example, obesity, an unhealthy diet and physical inactivity) and genetic factors contribute to the multiple pathophysiological disturbances that are responsible for impaired glucose homeostasis in T2DM. Insulin resistance and impaired insulin secretion remain the core defects in T2DM, but at least six other pathophysiological abnormalities contribute to the dysregulation of glucose metabolism. The multiple pathogenetic disturbances present in T2DM dictate that multiple antidiabetic agents, used in combination, will be required to maintain normoglycaemia. The treatment must not only be effective and safe but also improve the quality of life. Several novel medications are in development, but the greatest need is for agents that enhance insulin sensitivity, halt the progressive pancreatic β-cell failure that is characteristic of T2DM and prevent or reverse the microvascular complications. For an illustrated summary of this Primer, visit: http://go.nature.com/V2eGfN.

Point-of-Care HbA1c Testing with the A1cNow Test Kit in General Practice Dental Clinics: A Pilot Study Involving Its Accuracy and Practical Issues in Its Use

With millions of at-risk people undiagnosed with pre-diabetes and diabetes, there is a need to identify alternate screening sites for out-of-range glucose values. We examined practical issues and accuracy (relative to High Performance Liquid Chromatography testing in a laboratory) in the use of the A1cNow point of care device for this screening in general practice dental clinics at a large University-based Dental College. Health care professionals obtained evaluable readings for only 70% of the subjects, even after two attempts, and its use according to manufacturer's instructions was often challenging in the busy environment of the dental clinic. At thresholds for pre-diabetes and diabetes established by the American Diabetes Association, sensitivities of the A1cNow kit relative to the HPLC method were 91.9% and 100%, respectively. However, specificities for pre-diabetes and diabetes were 66.7% and 82.4%, respectively, indicating many false positive results. A better strategy for diabetes screening may involve a laboratory-based analysis approach that is patient- and provider-friendly, with minimal burden to the dental team.

Neuroactive steroid treatment modulates myelin lipid profile in diabetic peripheral neuropathy

Diabetic peripheral neuropathy causes a decrease in the levels of dihydroprogesterone and 5α-androstane-3α,17β-diol (3α-diol) in the peripheral nerves. These two neuroactive steroids exert protective effects, by mechanisms that still remain elusive. We have previously shown that the activation of Liver X Receptors improves the peripheral neuropathic phenotype in diabetic rats. This protective effect is accompanied by the restoration to control values of the levels of dihydroprogesterone and 3α-diol in peripheral nerves. In addition, activation of these receptors decreases peripheral myelin abnormalities by improving the lipid desaturation capacity, which is strongly blunted by diabetes, and ultimately restores the myelin lipid profile to non-diabetic values. On this basis, we here investigate whether dihydroprogesterone or 3α-diol may exert their protective effects by modulating the myelin lipid profile. We report that both neuroactive steroids act on the lipogenic gene expression profile in the sciatic nerve of diabetic rats, reducing the accumulation of myelin saturated fatty acids and promoting desaturation. These changes were associated with a reduction in myelin structural alterations. These findings provide evidence that dihydroprogesterone and 3α-diol are protective agents against diabetic peripheral neuropathy by regulating the de novo lipogenesis pathway, which positively influences myelin lipid profile.

The application of visceral adiposity index in identifying type 2 diabetes risks based on a prospective cohort in China

Background

Visceral adiposity index (VAI), a novel sex-specific index for visceral fat measurement, has been proposed recently. We evaluate the efficacy of VAI in identifying diabetes risk in Chinese people, and compare the predictive ability between VAI and other body fatness indices, i.e., waist circumference (WC), body mass index (BMI) and waist- to- height ratio (WHtR).

Methods

Participants (n = 3,461) were recruited from an ongoing cohort study in Jiangsu Province, China. Hazard ratio (HR) and corresponding 95% confidence interval (CI) between diabetes risk and different body fatness indices were evaluated by Cox proportional hazard regression model. Receiver operating characteristic (ROC) curve and area under curve (AUC) were applied to compare the ability of identifying diabetes risk between VAI, WC, WHtR and BMI.

Results

A total number of 160 new diabetic cases occurred during the follow-up, with an incidence of 4.6%. Significant positive associations were observed for VAI with blood pressure, fasting plasma glucose, triglyceride, WC, BMI and WHtR. Moreover, increased VAI was observed to be associated with higher diabetes risk with a positive dose–response trend (p for trend < 0.001). As compared to individuals with the lowest VAI, those who had the highest VAI were at 2.55-fold risk of diabetes (95% CI: 1.58-4.11). The largest AUC was observed for VAI, following by WC, WHtR and BMI.

Conclusions

VAI is positively associated with the risk of diabetes. Compared to other indices for body fatness measurements, VAI is a better and convenience surrogate marker for visceral adipose measurement and could be used in identifying the risk of diabetes in large-scale epidemiologic studies.

Psychosocial impacts of type 2 diabetes self-management in a rural African-American population

This qualitative study explored the underlying psychosocial factors and conditions that may influence type 2 diabetes (T2D) self-management among adult T2D-diagnosed African Americans in the Arkansas Delta. Listening to participants' narratives in their own voices provided meaningful insights in their real-life experiences of T2D-related psychological and emotional challenges in African American social cultural contexts. Self-determination theory was used to conceptualize the participants' motivations for making health behavior changes. Using purposive sampling, 31 participants total (16 women and 15 men) were interviewed. The study participants described their (1) concern over prescribed dietary and physical exercise guidelines as impractical and culturally not relevant to them; (2) doubts over the availability of social supports necessary to implement T2D self-management; and (3) fatalistic expectations of negative outcomes that undermined their self-motivation to follow self-management guidelines. Specific strategies for developing culturally competent T2D self management guidelines and community-based communication outreach initiatives are discussed.

A novel intraoral diabetes screening approach in periodontal patients: results of a pilot study

BACKGROUND

This pilot study examines whether a novel diabetes screening approach using gingival crevicular blood (GCB) could be used to test for hemoglobin A1c (HbA1c) during periodontal visits.

METHODS

Finger-stick blood (FSB) samples from 120 patients and GCB samples from those patients with adequate bleeding on probing (BOP) were collected on special blood collection cards and analyzed for HbA1c levels in a laboratory. The Pearson correlation coefficient was used to measure correlation between FSB and GCB HbA1c values for 75 paired FSB and GCB samples. A receiver-operator characteristic curve (ROC) analysis was performed to determine an optimal GCB HbA1c criterion value for a positive diabetes screen.

RESULTS

For the 75 paired samples, the Pearson correlation coefficient was 0.842. The ROC analysis identified a criterion value of 6.3% for the GCB HbA1c test with high sensitivity (0.933) and high specificity (0.900), corresponding to FSB HbA1c values ≥6.5% (in the diabetes range). Using this GCB HbA1c criterion value for 27 additional paired samples, in which there was an unidentified component observed to coelute within the elution window of GCB HbA1c in the laboratory, there was agreement between FSB and GCB values for 24 of the pairs according to whether both were within or outside of the diabetes range.

CONCLUSION

Using a criterion value of 6.3%, GCB samples are acceptable for HbA1c testing to screen for diabetes in most persons with BOP at the GCB collection site.

Diabetes-induced myelin abnormalities are associated with an altered lipid pattern: protective effects of LXR activation

Diabetic peripheral neuropathy (DPN) is characterized by myelin abnormalities; however, the molecular mechanisms underlying such deficits remain obscure. To uncover the effects of diabetes on myelin alterations, we have analyzed myelin composition. In a streptozotocin-treated rat model of diabetic neuropathy, analysis of sciatic nerve myelin lipids revealed that diabetes alters myelin's phospholipid, FA, and cholesterol content in a pattern that can modify membrane fluidity. Reduced expression of relevant genes in the FA biosynthetic pathway and decreased levels of the transcriptionally active form of the lipogenic factor sterol-regulatory element binding factor-1c (SREBF-1c) were found in diabetic sciatic nerve. Expression of myelin's major protein, myelin protein zero (P0), was also suppressed by diabetes. In addition, we confirmed that diabetes induces sciatic nerve myelin abnormalities, primarily infoldings that have previously been associated with altered membrane fluidity. In a diabetic setting, synthetic activator of the nuclear receptor liver X receptor (LXR) increased SREBF-1c function and restored myelin lipid species and P0 expression levels to normal. These LXR-modulated improvements were associated with restored myelin structure in sciatic nerve and enhanced performance in functional tests such as thermal nociceptive threshold and nerve conduction velocity. These findings demonstrate an important role for the LXR-SREBF-1c axis in protection from diabetes-induced myelin abnormalities.

Persistence of individual variations in glycated hemoglobin: analysis of data from the Juvenile Diabetes Research Foundation Continuous Glucose Monitoring Randomized Trial

OBJECTIVE

To determine the individual persistence of the relationship between mean sensor glucose (MG) concentrations and hemoglobin A(1c) (A1C) from the Juvenile Diabetes Research Foundation Continuous Glucose Monitoring (CGM) Randomized Trial.

RESEARCH DESIGN AND METHODS

MG was calculated using CGM data for 3 months before A1C measurements at 3, 6, 9, and 12 months for the CGM group and at 9 and 12 months for the control group. An MG-to-A1C ratio was included in analysis for subjects who averaged ≥4 days/week of CGM use.

RESULTS

Spearman correlations of the MG-to-A1C ratio between consecutive visits 3 months apart ranged from 0.70 to 0.79. The correlations for children and youth were slightly smaller than those for adults. No meaningful differences were observed by device type or change in A1C.

CONCLUSIONS

Individual variations in the rate of hemoglobin glycation are persistent and contribute to the inaccuracy in estimating MGs calculated from A1C levels.

Hypoglycemic effects of intraluminal intestinal electrical stimulation in healthy volunteers

BACKGROUND

Intestinal electrical stimulation (IES) has been shown to delay gastric emptying and reduce nutrient absorption in humans. The aim of this study was to investigate the effect of IES using an intraluminal method on postprandial blood glucose.

METHODS

An oral glucose tolerance test with 150 g of glucose was performed in 10 healthy volunteers with and without IES (13 pulses/min, 300 ms and 5 mA). An intraluminal catheter with a pair of ring electrodes was incubated into the duodenum under endoscopy and used for IES. Gastric emptying was performed simultaneously using an established ultrasonic technique.

RESULTS

(1) IES significantly decreased the postprandial glucose level from 15 min to 90 min after the glucose load. (2) The serum insulin level at 30 min but not other times after the meal was lower in the IES session than that in the control session (p = 0.06). (3) The half-time of gastric emptying with IES was increased from 27 ± 4.8 min in the control session to 36 ± 8.5 min with IES (p < 0.01). (4) The symptoms score of dyspepsia were almost the same between the two sessions except that IES induced a slightly higher nausea symptom score.

CONCLUSIONS

IES decreases postprandial blood glucose possibly by delaying gastric emptying and other unknown mechanisms and the intraluminal method of IES may serve as an excellent screening and research tool for various applications of IES. Further clinical studies are needed to explore therapeutic potentials of IES for diabetes.

The oral glucose tolerance test (OGTT) revisited

The oral glucose tolerance test (OGTT) has been the mainstay for diagnosing diabetes for decades. Recently, the American Diabetes Association (ADA) suggested abandoning the OGTT, while resorting to a simpler screening test, exclusively based on baseline fasting blood glucose concentration. This review article rewinds the history of OGTT and its recent advancements, and compares its power in detecting early diabetes with that of fasting blood glucose alone. The key point is that there are more diabetics originating from a population with normal fasting blood glucose than from subjects with impaired fasting glucose, those who can be detected by the new ADA recommendations. Conversely, the OGTT detects more efficiently early diabetes as well as subjects with IGT, as the glycemia at the second hour seems crucial as a diagnostic tool. We discuss the different significance of fasting versus second hour glycemia during OGTT, according to different mechanisms of glucose homeostasis. Finally, we provide recent evidence on very simple additional information that can be obtained from the OGTT, which renders this test even more useful, discussing pathophysiologic significance.

Insufficient sensitivity of hemoglobin A(₁C) determination in diagnosis or screening of early diabetic states

An International Expert Committee made recommendations for using the hemoglobin A(₁C) (A1C) assay as the preferred method for the diagnosis of diabetes in nonpregnant individuals. A concentration of at least 6.5% was considered as diagnostic. It is the aim of this study to compare the sensitivity of A1C with that of plasma glucose concentrations in subjects with early diabetes or impaired glucose tolerance (IGT). We chose 2 groups of subjects who had A1C not exceeding 6.4%. The first group of 89 subjects had family histories of diabetes (MODY or type 2 diabetes mellitus) and had oral glucose tolerance test (OGTT) and A1C determinations. They included 36 subjects with diabetes or IGT and 53 with normal OGTT. The second group of 58 subjects was screened for diabetes in our Diabetes Clinic by fasting plasma glucose, 2-hour plasma glucose, or OGTT and A1C; and similar comparisons were made. Subjects with diabetes or IGT, including those with fasting hyperglycemia, had A1C ranging from 5.0% to 6.4% (mean, 5.8%). The subjects with normal OGTT had A1C of 4.2% to 6.3% (mean, 5.4%), or 5.5% for the 2 groups. The A1C may be in the normal range in subjects with diabetes or IGT, including those with fasting hyperglycemia. Approximately one third of subjects with early diabetes and IGT have A1C less than 5.7%, the cut point that the American Diabetes Association recommends as indicating the onset of risk of developing diabetes in the future. The results of our study are similar to those obtained by a large Dutch epidemiologic study. If our aim is to recognize early diabetic states to apply effective prophylactic procedures to prevent or delay progression to more severe diabetes, A1C is not sufficiently sensitive or reliable for diagnosis of diabetes or IGT. A combination of A1C and plasma glucose determinations, where necessary, is recommended for diagnosis or screening of diabetes or IGT.

Factorial structure of the perception of risk factors for type 2 diabetes scale: exploratory and confirmatory factor analyses

RATIONALE, AIMS AND OBJECTIVES

The extent to which individuals' perceptions of risk for type 2 diabetes are related to their actual risks and health-promoting behaviours is not well known. Yet perception of risk for type 2 diabetes may influence the likelihood that individual would engage in preventive behaviours. The purpose of this study was to evaluate the psychometric properties of the perception of risk factors for type 2 diabetes (PRF-T2DM).

METHODS

A descriptive, correlational, methodological design was used to conduct this study. The sample consisted of 629 adults from 42 states of the United States. A demographic questionnaire, the PRF-T2DM, the health-promoting lifestyle profile II and the depressive cognition scale were used to collect the data. Data analyses consisted of descriptive statistics, scale and item analyses, Pearson's correlation analysis, and exploratory and confirmatory factor analyses.

RESULTS

The PRF-T2DM has a Cronbach's alpha of 0.81. Both extracted factors had Cronbach's alphas of 0.74 and 0.80, respectively. Most inter-item and item-to-total correlation coefficients for factor 1 and factor 2 met the recommended criteria of r=0.30 to r=0.70. The PRF-T2DM achieved all minimum recommended criteria for model fit (χ(2) /d.f.=2.33, goodness of fit index=0.95, adjusted goodness of fit index=0.93, comparative fit index=0.94, root mean square error of approximation=0.05, root mean residual=0.05 and the P value for test of close fit=0.33).

CONCLUSIONS

All statistical estimates and measures of model fit were above the standard recommended criteria. The scale has potential uses in research and clinical practice. Further development and psychometric evaluation of the PRF-T2DM is warranted.

Activation of the liver X receptor increases neuroactive steroid levels and protects from diabetes-induced peripheral neuropathy

Neuroactive steroids act in the peripheral nervous system as physiological regulators and as protective agents for acquired or inherited peripheral neuropathy. In recent years, modulation of neuroactive steroids levels has been studied as a potential therapeutic approach to protect peripheral nerves from damage induced by diabetes. Nuclear receptors of the liver X receptor (LXR) family regulate adrenal steroidogenesis via their ability to control cholesterol homeostasis. Here we show that rat sciatic nerve expresses both LRXα and β isoforms and that these receptors are functional. Activation of liver X receptors using a synthetic ligand results in increased levels of neurosteroids and protection of the sciatic nerve from neuropathy induced by diabetes. LXR ligand treatment of streptozotocin-treated rats increases expression in the sciatic nerve of steroidogenic acute regulatory protein (a molecule involved in the transfer of cholesterol into mitochondria), of the enzyme P450scc (responsible for conversion of cholesterol into pregnenolone), of 5α-reductase (an enzyme involved in the generation of neuroactive steroids) and of classical LXR targets involved in cholesterol efflux, such as ABCA1 and ABCG1. These effects were associated with increased levels of neuroactive steroids (e.g., pregnenolone, progesterone, dihydroprogesterone and 3α-diol) in the sciatic nerve, and with neuroprotective effects on thermal nociceptive activity, nerve conduction velocity, and Na(+), K(+)-ATPase activity. These results suggest that LXR activation may represent a new pharmacological avenue to increase local neuroactive steroid levels that exert neuroprotective effects in diabetic neuropathy.

Intestinal electrical stimulation decreases postprandial blood glucose levels in rats

BACKGROUND

Reducing postprandial blood glucose concentrations in diabetic patients might contribute to optimal glycemic control. Gastrointestinal electrical stimulation has been proposed as a novel therapy for both gastrointestinal motility disorders and obesity. The present study investigated the effects and underlying mechanisms of intestinal electrical stimulation (IES) on postprandial blood glucose levels in rats.

METHODS

Electrical stimulation electrodes were implanted into the duodenal wall of 33 male Sprague-Dawley rats. The blood glucose and insulin levels were measured before and after a glucose tolerance test both with and without electrical stimulation. In addition, the gastric emptying and intestinal flow rates were measured.

RESULTS

IES applied immediately after the glucose tolerance test caused a significant decrease in the rising phase slope and the maximal serum blood glucose level. Additionally, the area under the curve of the blood glucose levels was reduced by approximately 50%. Insulin secretion decreased by 21%. The main reduction in insulin secretion was during the first 30 minutes after the glucose tolerance test. IES also caused a nearly 80% decrease of the gastric emptying rate and a 40% increase in the flow rate of nutrients inside the intestine. The effect was immediate after IES activation and reversible.

CONCLUSION

These results suggest that IES applied to the duodenum can reduce postprandial blood glucose levels. The possible etiology is the modulating of gastric emptying and intestinal flow rate.

Early diagnosis and prevention of diabetes in developing countries

Type 2 diabetes has an insidious onset with a long latent period of dysglycaemia. By the time the diagnosis of diabetes is made, diabetes-related tissue damage occurs in nearly half of the patients. Even after diagnosis, the glycaemic control is suboptimal in more than 50%, leading to the vascular complications. Evidences suggest that early detection of diabetes by appropriate screening methods, especially in subjects with high risk for diabetes will help to prevent or delay the vascular complications and thus reduce the clinical, social and economic burden of the disease. There are also evidences to show that intervention at the prediabetic stage is superior to diagnosis of diabetes.

A new look at screening and diagnosing diabetes mellitus

OBJECTIVE

Diabetes is underdiagnosed. About one third of people with diabetes do not know they have it, and the average lag between onset and diagnosis is 7 yr. This report reconsiders the criteria for diagnosing diabetes and recommends screening criteria to make case finding easier for clinicians and patients.

PARTICIPANTS

R.M.B. invited experts in the area of diagnosis, monitoring, and management of diabetes to form a panel to review the literature and develop consensus regarding the screening and diagnosis of diabetes with particular reference to the use of hemoglobin A1c (HbA1c). Participants met in open session and by E-mail thereafter. Metrika, Inc. sponsored the meeting.

EVIDENCE

A literature search was performed using standard search engines.

CONSENSUS PROCESS

The panel heard each member's discussion of the issues, reviewing evidence prior to drafting conclusions. Principal conclusions were agreed on, and then specific cut points were discussed in an iterative consensus process.

CONCLUSIONS

The main factors in support of using HbA1c as a screening and diagnostic test include: 1) HbA1c does not require patients to be fasting; 2) HbA1c reflects longer-term glycemia than does plasma glucose; 3) HbA1c laboratory methods are now well standardized and reliable; and 4) errors caused by nonglycemic factors affecting HbA1c such as hemoglobinopathies are infrequent and can be minimized by confirming the diagnosis of diabetes with a plasma glucose (PG)-specific test. Specific recommendations include: 1) screening standards should be established that prompt further testing and closer follow-up, including fasting PG of 100 mg/dl or greater, random PG of 130 mg/dl or greater, or HbA1c greater than 6.0%; 2) HbA1c of 6.5-6.9% or greater, confirmed by a PG-specific test (fasting plasma glucose or oral glucose tolerance test), should establish the diagnosis of diabetes; and 3) HbA1c of 7% or greater, confirmed by another HbA1c- or a PG-specific test (fasting plasma glucose or oral glucose tolerance test) should establish the diagnosis of diabetes. The recommendations are offered for consideration of the clinical community and interested associations and societies.

Increased oxacillin resistance in thigh pyomyositis in diabetic patients

Thigh abscesses due to pyomyositis are uncommon. To guide empiric antibiotic therapy in diabetics we determined the rate of such infections due to oxacillin-resistant Staphylococcus aureus and Gram-negative organism infections, and whether the occurrence of oxacillin-resistant pathogens increased during the study period. We retrospectively reviewed 39 adult patients with diabetes mellitus treated for a deep thigh abscess. There were 29 men and 10 women; their mean age was 45 years. Comorbidities were present in 15 patients. S. aureus was the most common pathogen, present in 82% (32/39) of our patients. Gram-negative organisms were cultured in 14% (6/39) of patients and anaerobes in 10% (4/39). The infection was polymicrobial in 12 of 39 patients (31%). Oxacillin-resistant S. aureus comprised 25% (8/32) of infections due to S. aureus. Oxacillin-resistance increased during the last 3 years of this study from one of 18 S. aureus isolates from 1994 to 2004 to seven of 14 isolates from 2004 to 2006. In diabetic patients with thigh pyomyositis, empiric antibiotic therapy should provide broad spectrum coverage for oxacillin-resistant S. aureus, Gram-negative, as well as anaerobic organisms.

LEVEL OF EVIDENCE

Level IV, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Relationship of A1C to glucose concentrations in children with type 1 diabetes: assessments by high-frequency glucose determinations by sensors

OBJECTIVE

Despite the standing of A1C as the most validated and widely used measure for average glycemic control over time, the relationship between A1C and glucose concentrations is not completely understood. The purpose of this Diabetes Research in Children Network (DirecNet) study was to use continuous glucose monitoring data to examine the relationship between A1C and glucose in type 1 diabetes.

RESEARCH DESIGN AND METHODS

Forty-eight youth enrolled in studies of the Navigator continuous glucose monitor were encouraged to wear the Navigator sensor at home continuously. A1C was measured at baseline, at 3 months, and at 6 months. Sensor glucose data were directly transmitted via the Internet, assuring that essentially all glucose values were analyzed.

RESULTS

Subjects had a median of 112 h/week of Navigator data in the first 3 months and 115 h/week in the second 3 months. The slope of mean glucose over the previous 3 months versus A1C was only 18 mg/dl per 1.0% A1C. Individually, there was substantial variation in the relationship between mean glucose and A1C. A1C was not associated with glucose lability after controlling for mean glucose. Measures of an individual's rate of glycation were moderately correlated at the 3- and 6-month visits.

CONCLUSIONS

As the chemistry of glycation would predict, we found no evidence to contradict the simple hypothesis that A1C directly reflects mean glucose over time. There is, however, substantial variability in individual mean glucose concentrations for a given A1C. Transforming reliable A1C values into calculated mean glucose values would, when applied to an individual, introduce substantial error.