2010 consensus statement on the worldwide standardization of the hemoglobin A1c measurement

Effect of a Homemade Salivary Substitute Prepared Using Chamomile (Matricaria chamomilla L.) Flower and Flax (Linum usitatissimum L.) Seed to Relieve Primary Burning Mouth Syndrome: A Preliminary Report

Objectives: To evaluate (1) the effect of a salivary substitute prepared using chamomile (Matricaria chamomilla L.) flower and flax (Linum usitatissimum L.) seed to relieve Primary burning mouth syndrome (BMS) symptoms, (2) their effect on the inhibition of matrix metallopeptidase 2 (MMP2) and MMP9 metalloproteinases, and (3) their potential cellular cytotoxic effect. Subjects: 40 women aging >40 years with diagnosis of primary BMS. Settings/Location: Center of Diagnosis of Diseases of the Mouth, Federal University of Pelotas, Brazil. Design: This was an open clinical trial where primary BMS patients used the homemade salivary. At the first appointment, after 30 and 60 days, the authors evaluated the pattern and intensity of BMS and xerostomia symptoms, and then determined and compared the unstimulated salivary flow rate (SFR), viscosity, and salivary pH. MMP2 and MMP9 activities in saliva and cytotoxicity were assessed using different concentrations of chamomile flower and flax seed separately. Interventions: Subjects used the homemade salivary substitute for 3 months and were instructed to rinse their mouth three to four times daily for 1 min. Outcome measures: A numeric rating scale to evaluate the intensity of burning sensation and xerostomia symptoms, salivary flow rate (SFR) to determine salivary volume, dynamic rheology technique for viscosity and a digital meter for salivary pH. MMP2 and MMP9 activities in saliva and cytotoxicity were assessed by zymography and cell viability assay respectively. Results: After treatment, severity of BMS symptoms decreased, the SFR increased, salivary viscosity decreased, and severity of xerostomia sensation (in patients who reported having this symptom) improved (p < 0.05). Chamomile flower and flax seed had no effect on inhibiting MMP2 and MMP9 activities, and neither showed cellular cytotoxic effects. Conclusion: This homemade salivary substitute is an economical, viable, easily manipulated, noncytotoxic, and a practical alternative to relieve BMS symptoms.

Comparison of the International Federation of Clinical Chemistry and Japan Diabetes Society reference methods for conversion to the National Glycohemoglobin Standardization Program values

Background

The national programmes for the harmonization of haemoglobin A1c measurement in the US and Japan are based on differently designated comparison methods. The future basis for international standardization is expected to be the reference system developed by the International Federation of Clinical Chemistry (IFCC) Working Group on haemoglobin A1c Standardization. The aim of the present study is to compare the relationship between the IFCC reference method (RM) and Japanese Diabetes Society (JDS) RM used for the conversion to the National Glycohemoglobin Standardization Program (NGSP) values.

Methods

Three different method-comparison studies were performed. All blood samples were measured at the National Cerebral and Cardiovascular Centers (Lipid Reference Laboratories) that serve as Level 1 reference laboratories of the NGSP Network. Regression equations were calculated for the IFCC RM and JDS RM for the conversion to NGSP values.

Results

Differences were found between the haemoglobin A1c values of the IFCC RM and those of JDS. However, in all cases, the relationships of the IFCC RM and JDS RM were linear and commutable. The relationship is described by the following regression equations: NGSP-HbA1c = 0.915(IFCC-HbA1c) + 2.15% (r2 = 0.998); JDS/JSCC-HbA1c = 0.927(IFCC-HbA1c) + 1.73% (r2 = 0.997).

Conclusion

There is a firm and reproducible link between the IFCC and JDS-HbA1c values. However, the values calibrated by JDS RM were consistently and significantly higher than the IFCC values (0.1–0.2%) when used for conversion to the NGSP values.

Diversity, frequency and antifungal resistance of Candida species in patients with type 2 diabetes mellitus

OBJECTIVE

To determine number, species of Candida and Candida resistance to antifungal therapy according to the metabolic control state and the associated salivary changes in patients with type 2 diabetes mellitus (DM2).

MATERIALS AND METHODS

Samples of non-stimulated saliva were collected from 52 patients with DM2. Salivary pH was measured and cultured on Sabouraud glucose agar and the values of CFU/ml were calculated. The species were presumptively identified using CHROMagar Candida^® plates, and identification was confirmed by polymerase chain reaction (PCR). C. albicans isolates were cultured on SGA tetracycline agar with nystatin and fluconazole diffusion disks to measure susceptibility.

RESULTS

Sixty six percent of the yeasts isolated were Candida albicans, followed by C. glabrata (20.7%). In patients with decompensated DM2, there was an inverse association between HbA1c value and salivary pH. At higher levels of salivary acidification, a greater diversity and quantity of yeasts of the genus Candida were observed. With nystatin, higher inhibition was observed at lower pH.

CONCLUSIONS

The antifungal therapies could be more effective if it consider, qualitative salivary characteristics as pH, that could determine the susceptibility of species of Candida to at least to nystatin, which is the most used antifungal for treatment to oral candidiasis in patients with DM2.

Claimed effects, outcome variables and methods of measurement for health claims proposed under European Community Regulation 1924/2006 in the area of blood glucose and insulin concentrations

Most requests for authorization to bear health claims under Articles 13(5) and 14 related to blood glucose and insulin concentration/regulation presented to the European Food Safety Authority (EFSA) receive a negative opinion. Reasons for such decisions are mainly ascribable to poor substantiation of the claimed effects. In this scenario, a project was carried out aiming at critically analysing the outcome variables (OVs) and methods of measurement (MMs) to be used to substantiate health claims, with the final purpose to improve the quality of applications provided by stakeholders to EFSA. This manuscript provides a position statement of the experts involved in the project, reporting the results of an investigation aimed to collect, collate and critically analyse the information relevant to claimed effects (CEs), OVs and MMs related to blood glucose and insulin levels and homoeostasis compliant with Regulation 1924/2006. The critical analysis of OVs and MMs was performed with the aid of the pertinent scientific literature and was aimed at defining their appropriateness (alone or in combination with others) to support a specific CE. The results can be used to properly select OVs and MMs in a randomized controlled trial, for an effective substantiation of the claims, using the reference method(s) whenever available. Moreover, results can help EFSA in updating the guidance for the scientific requirements of health claims.

Clinical and experimental study on angiopoietin-like protein 8 associated with proliferative diabetic retinopathy

AIM

To confirm the role of angiopoietin-like protein 8 (Angptl 8) in proliferative diabetic retinopathy (PDR).

METHODS

The sera and aqueous humor of 10 PDR patients and 10 non-diabetic retinopathy (NDR) patients (idiopathic macular hole patients) were collected and the expression of Angptl 8 was detected by enzyme linked immune-sorbent assay (ELISA). Experimental diabetes mice model was induced with streptozotocin. The expression of glycosylated hemoglobin and Angptl 8 in sera was detected. Recombinant Angptl 8 was re-infused into wild type (WT) diabetic mice and spatial frequency threshold and contrast sensitivity were measured. In vitro retinal pigment epithelium (RPE) were stimulated by recombinant Angptl 8 for 24h. MMT assay were used to detect cell proliferation. At the same time, qRT-PCR and Western blot was used to measure the expression of proliferation-related factors in PRE cells.

RESULTS

The expression of Angptl 8 was markedly increased in the sera and aqueous humor of PDR patients (F=99.02, P<0.0001 in sera; t=10.42, P<0.0001 in aqueous). After successfully establishing the diabetic mice model, we found that glycosylated hemoglobin and Angptl 8 expression levels were increased. Re-infusion of recombinant Angptl 8 into WT diabetic mice could further decrease spatial frequency threshold and contrast sensitivity (P<0.01). In vitro, RPE cells stimulated by recombinant Angptl 8 could increase the relative absorbance of MMT assay (1.486±0.042 vs 1.000±0.104, P<0.05) and proliferating cell nuclear antigen (PCNA) expression (0.55±0.01 vs 0.29±0.03, P<0.05). The proliferative effect of Angptl 8 is mainly mediated by increasing the expression of proliferation-activating factors cyclin A1 (4.973±0.205 vs 2.720±0.197, P<0.05), cyclin F (5.690±0.219 vs 4.297±0.292, P<0.05) and E2F2 (2.297±0.102 vs 1.750±0.146, P<0.05), and reducing the expression of proliferation-inhibiting factors cdkn1 (2.370±0.074 vs 3.317±0.135, P<0.05) and cdkn2 (4.793±0.065 vs 5.387±0.149, P<0.05).

CONCLUSION

The expression of Angptl 8 is increased in PDR, and the increased Angptl 8 can promote proliferation and increase proliferation-related factors.

Glargine Insulin Use Versus Continuous Regular Insulin in Diabetic Surgical Noncritically Ill Patients Receiving Parenteral Nutrition: Randomized Controlled Study

BACKGROUND

Hyperglycemia is a major complication of parenteral nutrition (PN). Guidelines for hyperglycemia management in noncritically ill patients cite basal insulin administration but do not recommend a regimen. The GLUCOSE-in-PN study aimed to compare the efficacy of glargine insulin versus continuously infused regular insulin in PN (RI-in-PN) to achieve glycemic control in noncritically ill surgical patients with diabetes who were receiving PN.

METHODS

This prospective randomized open-label study was conducted at King Faisal Specialist Hospital and Research Centre. Noncritically ill surgical patients with diabetes who were receiving PN were randomized to receive basal glargine insulin or RI-in-PN on day 4 of PN support. Mean blood glucose levels were compared on study days 5-9. The percentages of blood glucose measurements at goal were compared between groups.

RESULTS

Sixty-seven PN treatment episodes were analyzed. There were no statistically significant differences in mean glucose levels between groups on any study day ( P > .1). Overall glycemic control rates were 52.24% (glargine insulin) and 47.76% (RI-in-PN; P = .06). A significantly higher percentage of hyperglycemia was observed on day 5 for glargine insulin versus RI-in-PN (22.39% vs 5.97%, P = .0059). Blood glucose measurements indicated 6 hypoglycemic events: 2 for glargine insulin (5.7%) and 4 for RI-in-PN (11.4%; P > .1).

CONCLUSION

Both glargine insulin and RI-in-PN are effective basal insulin modalities for blood glucose control in noncritically ill surgical patients with diabetes who are receiving PN. Uncontrolled hyperglycemic events occurred more frequently with glargine insulin, and the rate of hypoglycemia was acceptable for both regimens.

Metformin causes a futile intestinal-hepatic cycle which increases energy expenditure and slows down development of a type 2 diabetes-like state

OBJECTIVE

Metformin, the first line drug for treatment of type 2 diabetes, suppresses hepatic gluconeogenesis and reduces body weight in patients, the latter by an unknown mechanism.

METHODS

Mice on a high fat diet were continuously fed metformin in a therapeutically relevant dose, mimicking a retarded formulation.

RESULTS

Feeding metformin in pharmacologically relevant doses to mice on a high fat diet normalized HbA1c levels and ameliorated glucose tolerance, as expected, but also considerably slowed down weight gain. This was due to increased energy expenditure, since food intake was unchanged and locomotor activity was even decreased. Metformin caused lactate accumulation in the intestinal wall and in portal venous blood but not in peripheral blood or the liver. Increased conversion of glucose-1-¹³C to glucose-1,6-¹³C under metformin strongly supports a futile cycle of lactic acid production in the intestinal wall, and usage of the produced lactate for gluconeogenesis in liver.

CONCLUSIONS

The reported glucose-lactate-glucose cycle is a highly energy consuming process, explaining the beneficial effects of metformin given continuously on the development of a type 2 diabetic-like state in our mice.

The development of the metabolic syndrome and insulin resistance after adjuvant treatment for breast cancer

BACKGROUND

Adjuvant breast cancer treatment is associated with a number of adverse physical changes, including weight gain, and therefore may represent a critical period for the development of metabolic disturbance.

OBJECTIVE

The aim of this study was to evaluate changes in the presentation of the metabolic syndrome (MetSyn) and insulin resistance from breast cancer surgery to postcompletion of adjuvant treatment.

METHODS

Sixty-one participants who had completed metabolic screening, including fasting blood samples and anthropometric measurements, on the morning of breast cancer surgery were recruited. Measures were repeated after completion of adjuvant treatment. Change in the proportion of participants presenting with the MetSyn was evaluated using the related-samples McNemar test, and changes in measures of glucose metabolism (fasting insulin, insulin resistance [homeostatic model assessment index], and glycosylated hemoglobin [HbA1c]) were analyzed using paired t tests. The Kruskal-Wallis test was used to compare differences in changes in metabolic parameters across clinical and lifestyle characteristics.

RESULTS

There was a significant (P < .001) increase in fasting insulin (mean [SE] change, 2.73 [0.57] mU/L), homeostatic model assessment index (0.58 [0.14]), and HbA1c level (4.49 [5.63] mmol/mol) from baseline to follow-up along with an increase in the proportion diagnosed with the MetSyn (P = .03). Those with the MetSyn at diagnosis experienced a greater increase in insulin resistance. Premenopausal women experienced greatest increases in HbA1c level.

CONCLUSIONS

Results demonstrate the development of significant metabolic dysfunction, characterized by glucose dysmetabolism and MetSyn, after adjuvant treatment for breast cancer.

IMPLICATIONS FOR PRACTICE

Interventions to improve the metabolic profile of breast cancer survivors are warranted.

A randomised, controlled trial of the effects of a mobile telehealth intervention on clinical and patient-reported outcomes in people with poorly controlled diabetes

Objective

The objective of this research is to determine the effects of mobile telehealth (MTH) on glycosylated haemoglobin (HbA1c) and other clinical and patient-reported outcomes in insulin-requiring people with diabetes.

Methods

A nine-month randomised, controlled trial compared standard care to standard care supplemented with MTH (self-monitoring, mobile-phone data transmissions, graphical and nurse-initiated feedback, and educational calls). Clinical (HbA1c, blood pressure, daily insulin dose, diabetes outpatient appointments (DOAs)) and questionnaire data (health-related quality of life, depression, anxiety) were collected. Mean group changes over time were compared using hierarchical linear models and Mann-Whitney tests.

Results

Eighty-one participants with a baseline HbA1c of 8.98% ± 1.82 were randomised to the intervention ( n = 45) and standard care ( n = 36). The Group by Time effect revealed MTH did not significantly influence HbA1c ( p = 0.228), but p values were borderline significant for blood pressure ( p = 0.054) and mental-health related quality of life ( p = 0.057). Examination of effect sizes and 95% confidence intervals for mean group differences at nine months supported the existence of a protective effect of MTH on mental health-related quality of life as well as depression. None of the other measured outcomes were found to be affected by the MTH intervention.

Conclusions

Findings from this study must be interpreted with caution given the small sample size, but they do not support the widespread adoption of MTH to achieve clinically significant changes in HbA1c. MTH may, however, have positive effects on blood pressure and protective effects on some aspects of mental health.

Newly detected abnormal glucose regulation and long-term prognosis after acute myocardial infarction: Comparison of an oral glucose tolerance test and glycosylated haemoglobin A1c

BACKGROUND

An oral glucose tolerance test (OGTT) and/or glycosylated haemoglobin A1c (HbA1c) in patients with acute myocardial infarction (AMI) identify patients with increased mortality risk, but no comparison of the long-term prognostic values has yet been investigated.

METHODS

This study was a prospective cohort enrolling patients with AMI between 2002 until 2008 and follow-up until 1st October, 2012. Patients without known diabetes mellitus (DM) underwent an OGTT. Seventy-nine patients with known DM did not have an OGTT performed. Primary endpoint was all-cause mortality. We included 548 patients with AMI, of whom 469 underwent a standardized OGTT and were stratified according to OGTT and HbA1c.

RESULTS

During 9.8years of follow-up, 179 (33%) patients died. In patients having increased HbA1c ≥6.5%, a significantly increased mortality was observed (Hazard Ratio (HR) 1.60 [1.09-2.34]). However, when adjusting for known DM, no significance was detected. An OGTT did not show a significantly increased mortality, if used separately. A combined estimate showed a significantly increased mortality in patients categorized as newly diagnosed DM by OGTT and HbA1c<6.5% (HR 1.56 [95% CI 1.07-2.30]) compared to patients categorized as normal/impaired fasting glycaemia/impaired glucose tolerance by OGTT and HbA1c <6.5%. Approximately 50% of the patients with newly diagnosed DM by OGTT were only detected due to 2-hour post-load glucose values.

CONCLUSION

An OGTT is recommended in AMI patients without known DM and HbA1c<6.5%. Patients categorized as newly diagnosed DM by OGTT although HbA1c <6.5% share the same high risk of mortality as patients with HbA1c≥6.5%.

Effects of diabetes definition on global surveillance of diabetes prevalence and diagnosis: a pooled analysis of 96 population-based studies with 331,288 participants

BACKGROUND

Diabetes has been defined on the basis of different biomarkers, including fasting plasma glucose (FPG), 2-h plasma glucose in an oral glucose tolerance test (2hOGTT), and HbA1c. We assessed the effect of different diagnostic definitions on both the population prevalence of diabetes and the classification of previously undiagnosed individuals as having diabetes versus not having diabetes in a pooled analysis of data from population-based health examination surveys in different regions.

METHODS

We used data from 96 population-based health examination surveys that had measured at least two of the biomarkers used for defining diabetes. Diabetes was defined using HbA1c (HbA1c ≥6·5% or history of diabetes diagnosis or using insulin or oral hypoglycaemic drugs) compared with either FPG only or FPG-or-2hOGTT definitions (FPG ≥7·0 mmol/L or 2hOGTT ≥11·1 mmol/L or history of diabetes or using insulin or oral hypoglycaemic drugs). We calculated diabetes prevalence, taking into account complex survey design and survey sample weights. We compared the prevalences of diabetes using different definitions graphically and by regression analyses. We calculated sensitivity and specificity of diabetes diagnosis based on HbA1c compared with diagnosis based on glucose among previously undiagnosed individuals (ie, excluding those with history of diabetes or using insulin or oral hypoglycaemic drugs). We calculated sensitivity and specificity in each survey, and then pooled results using a random-effects model. We assessed the sources of heterogeneity of sensitivity by meta-regressions for study characteristics selected a priori.

FINDINGS

Population prevalence of diabetes based on FPG-or-2hOGTT was correlated with prevalence based on FPG alone (r=0·98), but was higher by 2-6 percentage points at different prevalence levels. Prevalence based on HbA1c was lower than prevalence based on FPG in 42·8% of age-sex-survey groups and higher in another 41·6%; in the other 15·6%, the two definitions provided similar prevalence estimates. The variation across studies in the relation between glucose-based and HbA1c-based prevalences was partly related to participants' age, followed by natural logarithm of per person gross domestic product, the year of survey, mean BMI, and whether the survey population was national, subnational, or from specific communities. Diabetes defined as HbA1c 6·5% or more had a pooled sensitivity of 52·8% (95% CI 51·3-54·3%) and a pooled specificity of 99·74% (99·71-99·78%) compared with FPG 7·0 mmol/L or more for diagnosing previously undiagnosed participants; sensitivity compared with diabetes defined based on FPG-or-2hOGTT was 30·5% (28·7-32·3%). None of the preselected study-level characteristics explained the heterogeneity in the sensitivity of HbA1c versus FPG.

INTERPRETATION

Different biomarkers and definitions for diabetes can provide different estimates of population prevalence of diabetes, and differentially identify people without previous diagnosis as having diabetes. Using an HbA1c-based definition alone in health surveys will not identify a substantial proportion of previously undiagnosed people who would be considered as having diabetes using a glucose-based test.

FUNDING

Wellcome Trust, US National Institutes of Health.

Aiming for better glucose control: is HbA(1c) of 7% the 'holy grail'? The clinical approach or seven clinical questions about 7

The diabetes epidemic imposes a substantial burden on health systems and economy all over the world. Over the last two decades, many health systems adopted health care quality and performance measures for diabetes mellitus, most notably haemoglobin A(1c). This article raises concerns regarding the significance of HbA(1c) as a performance measure and emphasizes the need for individualized therapy.

Randomized, controlled trial of glucose-sparing peritoneal dialysis in diabetic patients

Glucose-containing peritoneal dialysis solutions may exacerbate metabolic abnormalities and increase cardiovascular risk in diabetic patients. Here, we examined whether a low-glucose regimen improves metabolic control in diabetic patients undergoing peritoneal dialysis. Eligible patients were randomly assigned in a 1:1 manner to the control group (dextrose solutions only) or to the low-glucose intervention group (IMPENDIA trial: combination of dextrose-based solution, icodextrin and amino acids; EDEN trial: a different dextrose-based solution, icodextrin and amino acids) and followed for 6 months. Combining both studies, 251 patients were allocated to control (n=127) or intervention (n=124) across 11 countries. The primary endpoint was change in glycated hemoglobin from baseline. Mean glycated hemoglobin at baseline was similar in both groups. In the intention-to-treat population, the mean glycated hemoglobin profile improved in the intervention group but remained unchanged in the control group (0.5% difference between groups; 95% confidence interval, 0.1% to 0.8%; P=0.006). Serum triglyceride, very-low-density lipoprotein, and apolipoprotein B levels also improved in the intervention group. Deaths and serious adverse events, including several related to extracellular fluid volume expansion, increased in the intervention group, however. These data suggest that a low-glucose dialysis regimen improves metabolic indices in diabetic patients receiving peritoneal dialysis but may be associated with an increased risk of extracellular fluid volume expansion. Thus, use of glucose-sparing regimens in peritoneal dialysis patients should be accompanied by close monitoring of fluid volume status.