Screening for diabetes with HbA1c: Test performance of HbA1c compared to fasting plasma glucose among Chinese, Malay and Indian community residents in Singapore

Prediabetes and diabetes in India: An HbA1c based epidemiology study

BACKGROUND

The relentless rise in Type 2 diabetes mellitus (T2DM) and prediabetes presents a complex challenge to India's healthcare system. This study analyses the prevalence and trends of these conditions in adults across Indian states using laboratory data collected during 2023.

METHODS

HbA1c values from 19,66,449 samples from adults alongside demographic and geographic details were retrospectively analysed. Data were stratified by state, age, and gender, and evaluated against national statistics parameters such as food consumption and socio-economic status.

RESULTS

Substantial regional variation was seen across the country where 22.25% of the tested population was considered having prediabetes, and 27.18% with diabetes. Odisha had the highest rates, while J&K reported the lowest. Gender-specific trends indicate an increase in prevalence of diabetes among males compared to females. Age-wise data stratification show a significant burden of prediabetes and diabetes in the economically productive age groups. Correlations between disease prevalence and state-specific grain consumption were observed, suggesting dietary influences.

CONCLUSIONS

The reported prevalence of prediabetes and diabetes higher than previous studies highlights the importance of regular screening. The use of HbA1c for estimation as a long-term average blood sugar marker helps to identify previously undiagnosed diabetes. The correlation of prevalence with food production underscores the importance of diet in disease management.

Influence of High-Altitude Residential History on Optimal HbA1c Cutoff for Detecting Abnormal Glucose Metabolism

Aims: To explore the influence of recent high-altitude residential history on the optimal cutoff of glycosylated hemoglobin (HbA1c) for detecting abnormal glucose metabolism. Methods: The study included 505 self-reported healthy Han participants of age 18-65 years, recruited in Chengdu and categorized based on recent (within 3 months) high-altitude (>2,500 m) residential history. The 1999 WHO criteria was used as the gold standard for defining prediabetes and diabetes. HbA1c test performance was assessed using receiver operating characteristic curve, with the optimal cutoff determined by Maximum Youden index. Propensity score matching with 0.02 calipers and nearest neighbor method was used to balance confounding factors between groups. Results: Of the participants, 238 (47.13%) were populations with recent high-altitude residential history (HA group), and 267 (52.87%) were low-altitude dwellers (LA group). The HA group had slightly higher HbA1c levels (p > 0.05) and higher erythrocyte and hemoglobin levels (p < 0.05), compared to the LA group. Weak correlations between prediabetes and HbA1c levels were observed in the HA group (rs = 0.21, p < 0.05) and the LA group (rs = 0.07, p = 0.25). The optimal cutoff for the detection of diabetes was 6.5% (area under the curve [AUC] 0.94) in the HA group and 5.9% (AUC 0.97) in the LA group, which remained unchanged after adjustment for confounders. Conclusions: The optimal cutoff of HbA1c for the detection of diabetes in populations with recent history of living at high altitude was higher than that in general populations living at low altitude, and the diagnostic value of HbA1c for prediabetes was also inadequate.

An incidental finding of a hemoglobin E variant in a diabetic patient with an abnormal glycated hemoglobin level: a case report

BACKGROUND

Glycated hemoglobin is a well-known marker for evaluating long-term glycemic control. However, the accuracy of glycated hemoglobin measurement can be affected by the presence of hemoglobin variants, which makes the determination and interpretation of glycated hemoglobin values in terms of glycemic control not only difficult but also misleading. Here we present the first ever case of a patient with type 2 diabetes with hemoglobin E from Nepal, diagnosed incidentally because of spurious glycated hemoglobin levels.

CASE PRESENTATION

A 45-year-old Hindu Mongolian female with a history of type 2 diabetes for around 9 years but not very compliant with follow-ups was referred to our facility for plasma fasting and postprandial blood glucose levels and glycated hemoglobin. Fasting and postprandial blood sugars were found to be high. A consistent very low glycated hemoglobin by two different high-performance liquid chromatography (HPLC) methods compelled us to call the patient for a detailed clinical history and for the records of investigations done in the past. The patient has been a known case of type 2 diabetes for around 9 years and presented irregularly for follow-up visits. Around 4 years ago, she presented to a healthcare facility with fatigue, severe headaches, pain in the abdomen, discomfort, and dizziness for a couple of months, where she was shown to have high blood glucose. She was referred to a tertiary-level hospital in Kathmandu, where she was prescribed metformin 500 mg once daily (OD). Due to her abnormal hemoglobin A1c reports, she was then sent to the National Public Health Laboratory for repeat investigations. Her blood and urine investigations were sent. Complete blood count findings revealed high red blood cell and white blood cell counts, a low mean corpuscular volume, and a high red cell distribution width-coefficient of variation. Other parameters, including serum electrolytes, renal function tests, liver function tests, and urine routine examinations, were within normal limits. A peripheral blood smear revealed microcytic hypochromic red cells with some target cells. Hemoglobin electrophoresis showed a very high percentage of hemoglobin E, a very low percentage of hemoglobin A2, and normal proportions of hemoglobin A and hemoglobin F. A diagnosis of homozygous hemoglobin E was made, and family screening was advised.

CONCLUSIONS

Clinicians should be aware of the limitations of glycated hemoglobin estimation by ion exchange high-performance liquid chromatography in patients with hemoglobin E and other hemoglobin variants. If the clinical impression and glycated hemoglobin test results do not match, glycated hemoglobin values should be determined with a second method based on a different principle, and glycemic status should be confirmed through alternative investigations, preferably those that are not influenced by the presence of hemoglobin variants (for example, boronate affinity chromatography, fructosamine test, glycated albumin test, the oral glucose tolerance test, continuous glucose monitoring, etc.). Consistent or even doubtful results should also raise the suspicion of a hemoglobin variant, which should be confirmed through further evaluation and investigations.

WhatsApp-based intervention for people with type 2 diabetes: A randomized controlled trial

Diabetes mellitus is a metabolic disease characterized by prolonged elevated blood glucose levels. Diabetes self-management education and support programs are widely used in western countries. The impact of social media education and support interventions such as a WhatsApp-based program and the nurses' role in supporting and implementing this self-management program unclear. Using a WhatsApp-based program, we evaluated the effects of a 6-week program in improving self-efficacy and education among people with type 2 diabetes mellitus in Saudi Arabia. Eligible participants (n = 80) were recruited with the support of nurses into a randomized controlled trial and randomly assigned into self-management intervention and control groups. The intervention group (n = 40) received the self-management program support and the usual care. The control group (n = 40) received only the usual care with nurses' support. Results from generalized estimating equation analysis showed a significant increase in self-efficacy, self-management, and education in the WhatsApp-based intervention support group compared with the control group at 6 and 12 weeks (follow-up). Implementing the program via social media improves self-efficacy. The use of social media platforms should be promoted for global diabetes management.

Association of Glutathione Peroxidase 3 (GPx3) and miR-196a with Carbohydrate Metabolism Disorders in the Elderly

The escalating prevalence of carbohydrate metabolism disorders (CMDs) prompts the need for early diagnosis and effective markers for their prediction. Hyperglycemia, the primary indicator of CMDs including prediabetes and type 2 diabetes mellitus (T2DM), leads to overproduction of reactive oxygen species (ROS) and oxidative stress (OxS). This condition, resulting from chronic hyperglycemia and insufficient antioxidant defense, causes damage to biomolecules, triggering diabetes complications. Additionally, aging itself can serve as a source of OxS due to the weakening of antioxidant defense mechanisms. Notably, previous research indicates that miR-196a, by downregulating glutathione peroxidase 3 (GPx3), contributes to insulin resistance (IR). Additionally, a GPx3 decrease is observed in overweight/obese and insulin-resistant individuals and in the elderly population. This study investigates plasma GPx3 levels and miR-196a expression as potential CMD risk indicators. We used ELISA to measure GPx3 and qRT-PCR for miR-196a expression, supplemented by multivariate linear regression and receiver operating characteristic (ROC) analysis. Our findings included a significant GPx3 reduction in the CMD patients (n = 126), especially in the T2DM patients (n = 51), and a decreasing trend in the prediabetes group (n = 37). miR-196a expression, although higher in the CMD and T2DM groups than in the controls, was not statistically significant, potentially due to the small sample size. In the individuals with CMD, GPx3 levels exhibited a negative correlation with the mass of adipose tissue, muscle, and total body water, while miR-196a positively correlated with fat mass. In the CMD group, the analysis revealed a weak negative correlation between glucose and GPx3 levels. ROC analysis indicated a 5.2-fold increased CMD risk with GPx3 below 419.501 ng/mL. Logistic regression suggested that each 100 ng/mL GPx3 increase corresponded to a roughly 20% lower CMD risk (OR = 0.998; 95% CI: 0.996-0.999; p = 0.031). These results support the potential of GPx3 as a biomarker for CMD, particularly in T2DM, and the lack of a significant decline in GPx3 levels in prediabetic individuals suggests that it may not serve reliably as an early indicator of CMDs, warranting further large-scale validation.

Discrepancy in diagnoses of diabetes and prediabetes using fasting plasma glucose and glycosylated hemoglobin and the underdiagnosis by ICD-10 coding: data from a tertiary hospital in Thailand

Background

Early detection of prediabetes and diabetes better prevents long-term health complications. FPG and HbA1c levels are some common laboratory tests utilized as tools to diagnose diabetes and prediabetes, but the agreement rate between these two diagnostic tests varies, which could lead to underdiagnosis and thus undertreatment. This study aimed to analyze the agreement rate between FPG and HbA1c, as well as the physicians' accuracy of using these results to make a prediabetes or diabetes diagnosis through ICD-10 coding at a tertiary care hospital in Bangkok, Thailand.

Methods

A cross-sectional descriptive study was conducted using secondary data collected in a tertiary hospital's check-up clinic from August 16, 2019 to June 30, 2022 to study the prevalence and diagnosis of diabetes and prediabetes, determined through FPG and HbA1c laboratory results. We analyzed the two laboratory tests' diagnosis agreement rate and the physicians' accuracy of diagnosing diabetes and prediabetes in ICD-10 coding using the FPG and HbA1c results.

Results

Among 8,024 asymptomatic participants, the period prevalence diagnosed through laboratory results was 5.8% for diabetes and 19.8% for prediabetes. Diabetes and prediabetes prevalence based on laboratory data differs from that of ICD-10 coding data. Specifically, 79.6% of diabetes patients and 32.3% of prediabetes patients were coded using the ICD-10 coding system. 4,094 individuals had both FPG and HbA1c data. The agreement rate for diagnosing diabetes and prediabetes between the two laboratory results is 89.5%, with Kappa statistics of 0.58. Using only one of the two laboratory results would have missed a substantial number of patients.

Conclusion

Our findings highlight screening test discrepancies and underdiagnosis issues that impede diagnostic accuracy enhancement and refined patient management strategies. Early diagnoses of prediabetes and diabetes, especially before symptoms arise, could increase health consciousness in individuals, thereby enabling the implementation of lifestyle modifications and prevention of serious health complications. We emphasize the importance of diagnosing these conditions using both FPG and HbA1c, along with subsequent accurate ICD-10 coding. Even though some hospitals lack certified HbA1c testing, we suggest enhancing the availability of HbA1c testing, which could benefit many people in Thailand.Clinical trial registration:https://www.thaiclinicaltrials.org, identifier [TCTR20230824003].

Hyperglycemia and glucose variability are associated with worse survival in mechanically ventilated COVID-19 patients: the prospective Maastricht Intensive Care Covid Cohort

BACKGROUND

Data on hyperglycemia and glucose variability in relation to diabetes mellitus, either known or unknown in ICU-setting in COVID-19, are scarce. We prospectively studied daily glucose variables and mortality in strata of diabetes mellitus and glycosylated hemoglobin among mechanically ventilated COVID-19 patients.

METHODS

We used linear-mixed effect models in mechanically ventilated COVID-19 patients to investigate mean and maximum difference in glucose concentration per day over time. We compared ICU survivors and non-survivors and tested for effect-modification by pandemic wave 1 and 2, diabetes mellitus, and admission HbA1c.

RESULTS

Among 232 mechanically ventilated COVID-19 patients, 21.1% had known diabetes mellitus, whereas 16.9% in wave 2 had unknown diabetes mellitus. Non-survivors had higher mean glucose concentrations (ß 0.62 mmol/l; 95%CI 0.20-1.06; ß 11.2 mg/dl; 95% CI 3.6-19.1; P = 0.004) and higher maximum differences in glucose concentrations per day (ß 0.85 mmol/l; 95%CI 0.37-1.33; ß 15.3; 95%CI 6.7-23.9; P = 0.001). Effect modification by wave, history of diabetes mellitus and admission HbA1c in associations between glucose and survival was not present. Effect of higher mean glucose concentrations was modified by pandemic wave (wave 1 (ß 0.74; 95% CI 0.24-1.23 mmol/l) ; (ß 13.3; 95%CI 4.3-22.1 mg/dl)) vs. (wave 2 (ß 0.37 (95%CI 0.25-0.98) mmol/l) (ß 6.7 (95% ci 4.5-17.6) mg/dl)).

CONCLUSIONS

Hyperglycemia and glucose variability are associated with mortality in mechanically ventilated COVID-19 patients irrespective of the presence of diabetes mellitus.

Measures of carbohydrate quality and their association with diet quality and cardiometabolic health outcomes in Singapore middle-aged and older adults

BACKGROUND AND AIMS

Carbohydrate quality may play a key role in cardiometabolic health and disease risk. This study aimed to assess the dietary carbohydrate quality of the free-living middle-aged and older adults in Singapore, and its association with overall diet quality and cardiometabolic health.

METHODS AND RESULTS

This cross-sectional study examined the diet and cardiometabolic disease risk indicators of middle-aged and older adults in Singapore (n = 104). Dietary carbohydrate quality was assessed as the pass and fail rate of the population to four measures of carbohydrate quality: (i) dietary fiber recommended daily allowance (RDA), (ii) whole-grain recommendation, (iii) free sugar recommendation, and (iv) carbohydrate metrics. The association between each carbohydrate quality measure and diet quality, as well as cardiometabolic health, was assessed. Except for free sugar recommendation, the carbohydrate quality of the population was found to be poor with a low adherence (20-36%) to three measures. Subjects meeting these measures had generally higher intakes of fiber, protein, and most micronutrients compared with subjects who failed. Meeting different variants of the carbohydrate metrics was associated with 60% lower odds of pre-hypertensive blood pressure (p = 0.037; p = 0.047), and meeting the dietary fiber RDA was associated with lower waist circumference (p = 0.021).

CONCLUSION

An improvement in carbohydrate quality is warranted among free-living middle-aged and older adults in Singapore. Not all measures of carbohydrate quality were equally effective in preserving overall diet quality; the carbohydrate metrics and dietary fiber RDA can be identified as effective measures in relation to cardiometabolic disease risk.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ CLINICAL TRIAL REGISTRATION: NCT03554954, 13 Sept. 2018.

Association of salivary alpha-2-macroglobulin with glycemia and glycated hemoglobin in type 2 diabetes mellitus: a systematic review and meta-analysis study

BACKGROUND

Chronically elevated alpha-2-macroglobulin (A2MG) in the blood has been correlated with diabetes and the HbA1c profile; however, no systematic review has been conducted to evaluate the association of A2MG salivary levels and glycemia or HbA1c levels in diabetes mellitus type 2 (DM2) patients.

OBJECTIVE

To evaluate whether A2MG salivary levels are related to the glycemia or HbA1c levels in DM2 patients.

DESIGN AND SETTING

Systematic review developed at Universidade Federal de Uberlândia (UFU), Brazil.

METHODS

Eight databases were used as research sources. The eligibility criteria included studies that reported data regarding mean salivary A2MG and the correlation between glycemia and/or HbA1c levels of DM2 subjects (uncontrolled and well-controlled) and non-diabetic subjects. The risk of bias of the studies selected was assessed using the Joanna Briggs Institute (JBI) critical appraisal tools for use in JBI systematic reviews. Pooled correlation coefficients were estimated using the Hunter-Schmidt method. Study estimates were weighted according to their sample size, and heterogeneity was calculated using the chi-square statistic.

RESULTS

Four studies on DM2 patients were included in this systematic review after careful analysis of 1482 studies. Three studies compared A2MG with HbA1c and glycemia. Overall, the correlation between A2MG and HbA1c was strong (r = 0.838). In contrast, the correlation between A2MG and glycemia was low (r = 0.354).

CONCLUSION

The strong association between HbA1C and salivary A2MG suggests that this salivary protein has the potential to be a surrogate for HbA1C, if corroboratory further evidence is obtained through large-scale studies.

Diabetes Prevalence and Associated Risk Factors among Women in a Rural District of Nepal Using HbA1c as a Diagnostic Tool: A Population-Based Study

Given the scarcity of data on diabetes prevalence and associated risk factors among women in rural Nepal, we aimed to examine this, using glycated hemoglobin (HbA1c) as a diagnostic tool. A cross-sectional survey addressing reproductive health and non-communicable diseases was conducted in 2012–2013 among non-pregnant, married women in Bolde, a rural district of Nepal. HbA1c ≥ 6.5% (48 mmol/mol) was used as diagnostic criterion for diabetes, a cut-off of 7.0% (53 mmol/mol) was used to increase the specificity. HbA1c was measured in 757 women (17–86 years). The prevalence of diabetes and prediabetes was 13.5% and 38.5%, respectively. When using 7.0% as a cut-off, the prevalence of diabetes was 5.8%. Aging, intake of instant noodles and milk and vegetarian food (ns) were associated with increased risk for diabetes. Waist circumference was higher among women with diabetes, although not significant. The women were uneducated (87.6%), and only 12% had heard about diabetes. In conclusion, we observed a higher prevalence of diabetes and prediabetes than anticipated among rural, Nepalese women. The increased risk was mainly attributed to dietary factors. In contrast to most previous studies in Nepal, we used HbA1c as diagnostic criterion.

Concordance in incidence of diabetes among persons with prediabetes detected using either oral glucose tolerance test or glycated haemoglobin

AIMS

To study the concordance in the incidence of type 2 diabetes (T2DM) between cohorts with prediabetes, selected either by oral glucose tolerance test (OGTT) or glycosylated haemoglobin (HbA1c) at two years in a real world situation.

METHODS

Two cohorts with impaired glucose tolerance (IGT) were selected from the non-interventional arm of the Indian diabetes prevention programmes; a group selected by using OGTT (Cohort 1, n = 498), another selected based on the HbA1c criterion (Cohort 2, n = 504). Clinical and biochemical data collected for 24 months at 6 monthly intervals were used in assessing the cumulative incidence of T2DM using the respective diagnostic criteria. Intra and inter group comparisons were analysed using appropriate statistical tests. A multiple logistic regression analysis was used to identify the variables significantly associated with the incidence of diabetes.

RESULTS

Incidence of diabetes in both cohorts were similar at 12 and 24 months with either of the two criteria (25.3% with glucose and 27.5% with HbA1c, p = 0.41 at 24 months). The multivariate analysis confirmed the results. Only baseline waist circumference was positively associated with the incidence.

CONCLUSION

Both OGTT and HbA1c have similar utility and validity in identifying persons with IGT. Persons identified with either of the criterion had similar incidence of T2DM among Asian Indians.

Influence of red blood cell indices on HbA1c performance in detecting dysglycaemia in a Singapore preconception cohort study

Abnormalities of red blood cell (RBC) indices may affect glycated haemoglobin (HbA1c) levels. We assessed the influence of haemoglobin (Hb) and mean corpuscular volume (MCV) on the performance of HbA1c in detecting dysglycaemia among reproductive aged women planning to conceive. Women aged 18-45 years (n = 985) were classified as normal (12 ≤ Hb ≤ 16 g/dL and 80 ≤ MCV ≤ 100 fL) and abnormal (Hb < 12 g/dL and/or MCV < 80 fL). The Area Under the Receiver Operating Characteristic (AUROC) curve was used to determine the performance of HbA1c in detecting dysglycaemic status (prediabetes and diabetes). There were 771 (78.3%) women with normal RBC indices. The AUROCs for the normal and abnormal groups were 0.75 (95% confidence interval 0.69, 0.81) and 0.80 (0.70, 0.90), respectively, and were not statistically different from one another [difference 0.04 (- 0.16, 0.08)]. Further stratification by ethnicity showed no difference between the two groups among Chinese and Indian women. However, Malay women with normal RBC indices displayed lower AUROC compared to those with abnormal RBC indices (0.71 (0.55, 0.87) vs. 0.98 (0.93, 1.00), p = 0.002). The results suggest that the performance of HbA1c in detecting dysglycaemia was not influenced by abnormal RBC indices based on low Hb and/or low MCV. However, there may be ethnic variations among them.

Human SHC-transforming protein 1 and its isoforms p66shc: A novel marker for prediabetes

AIMS

Prediabetes is a multifactorial condition. Current guidelines for diabetes screening recommend either the use of glycated hemoglobin (HbA1c), or blood glucose level (BGL). This research aimed to identify if p66shc a component of the Human SHC-Transforming Protein 1 (Shc1), a mitochondrial associated oxidative stress biomarker, is significantly altered in patients with elevated BGL. Furthermore, we evaluated if inflammatory and oxidative stress markers, such as p66shc, are a useful addition to the regularly used biomarkers to increase sensitivity for identification of prediabetes.

METHODS

All participants attended the Diabetic Health Screening at Charles Sturt University (CSU), Australia. The cross-sectional clinical study collected demographic and clinical variables from 346 participants and classified into control or prediabetes based on fasting BGL. Blood and urine samples were analyzed for oxidative stress and inflammation markers. Logistic regression was used to compare multidimensional diagnostic models for prediabetes, including p66shc/Shc1, to the current HbA1c-only model in terms of sensitivity, specificity and predictive accuracy. Significance was set at P ≤ 0.05.

RESULTS

A significant decrease of p66shc/Shc1 was determined in prediabetes compared to controls (P ≤ 0.05). HbA1c testing resulted in an accuracy of 62%, while adding p66shc and triglycerides increased predictive accuracy to 88.05%. When HbA1c was omitted and Shc1 was combined with 8-hydroxy-2'-deoxyguanosine (8-OHdG) and monocyte chemo-attractant protein-1 (MCP-1), a predictive accuracy of 89.5% was achieved.

CONCLUSION

Our findings showed a major improvement of sensitivity to identify prediabetes by including oxidative stress and inflammatory biomarkers underlining beneficial diagnostic information, which most likely improves prevention and early treatment options in prediabetes.

Agriophyllum Oligosaccharides Ameliorate Diabetic Insulin Resistance Through INS-R/IRS/Glut4-Mediated Insulin Pathway in db/db Mice and MIN6 Cells

We have previously reported that Agriophyllum oligosaccharides (AOS) significantly enhance glycemic control by increasing the activation of insulin receptor (INS-R), insulin receptor substrate-2 (IRS-2), phosphatidylinositol 3 kinase (PI3K), protein kinase B (AKT), peroxisome proliferator-activated receptor (PPAR)-γ, and glucose transporter 4 (Glut4) proteins in hepatic tissues. However, the effect of glucose control by AOS on the regulation of pancreatic tissues in db/db mice and MIN6 cells remains to be determined. An oral dose of AOS (380 or 750 mg/kg) was administered to type-2 diabetic db/db mice for 8 weeks to determine whether AOS regulates glucose by the INS-R/IRS/Glut4-mediated insulin pathway. Meanwhile, the effects of AOS on glucose uptake and its related signaling pathway in MIN6 cells were also investigated. The results showed that the random blood glucose (RBG) level in the AOS-treated group was lower than that in the control group. AOS reduced the levels of glycated hemoglobin (HbA1c) and free fatty acid (FFA) and significantly improved the pathological changes in the pancreatic tissues in db/db mice. Moreover, immunohistochemical analysis revealed that the expression of INS-R, IRS-1, IRS-2, and Glut4 was increased in the AOS-treated group than in the model group. Further, in vitro experiments using MIN6 cells showed that AOS regulated INS-R, IRS-1, IRS-2, and Glut4 protein and mRNA levels and attenuated insulin resistance and cell apoptosis. The results of both in vitro and in vivo experiments were comparable. Ultra-performance liquid chromatography coupled with time-of-flight mass spectrometric analysis of AOS with precolumn derivatization with 3-amino-9-ethylcarbazole (AEC) tentatively identified five types of sugars: glucose, lactose, rutinose, glucuronic acid, and maltotriose. Our present study clearly showed that AOS is efficacious in preventing hyperglycemia, possibly by increasing insulin sensitivity and improving IR by regulating the INS-R/IRS/Glut4 insulin signal pathway. Therefore, AOS may be considered as a potential drug for diabetes treatment.

Discordance between Fasting Plasma Glucose (FPG) and HbA1c in Diagnosing Diabetes and Pre-diabetes in The Malaysian Cohort

OBJECTIVE

In this present study, we aim to evaluate the accuracy of the HbA1c relative to fasting plasma glucose (FPG) in the diagnosis of diabetes and pre-diabetes among The Malaysian Cohort (TMC) participants.

METHODOLOGY

FPG and HbA1c were taken from 40,667 eligible TMC participants that have no previous history of diabetes, aged between 35-70 years and were recruited from 2006 - 2012. Participants were classified as normal, diabetes and pre-diabetes based on the 2006 World Health Organization (WHO) criteria. Statistical analyses were performed using ANOVA and Chi-square test, while Pearson correlation and Cohen's kappa were used to examine the concordance rate between FPG and HbA1c.

RESULTS

The study samples consisted of 16,224 men and 24,443 women. The prevalence of diabetes among the participants was 5.7% and 7.5% according to the FPG and HbA1c level, respectively. Based on FPG, 10.6% of the participants had pre-diabetes but this increased to 14.2% based on HbA1c (r=0.86; P<0.001). HbA1c had a sensitivity of 58.20 (95% CI: 56.43, 59.96) and a specificity of 98.59 (95% CI: 98.46, 98.70).

CONCLUSION

A higher prevalence of pre-diabetes and diabetes was observed when using HbA1c as a diagnosis tool, suggesting that it could possibly be more useful for early detection. However, given that HbA1c may also have lower sensitivity and higher false positive rate, several diagnostic criteria should be used to diagnose diabetes accurately.

Community-based educational interventions for prevention of type II diabetes: a global systematic review and meta-analysis

PURPOSE

Our objective was to estimate the change in community-based education interventions throughout the world that may effectuate in risk parameters of type II diabetes (T2D), including the diabetes incidence rate, fasting blood glucose, hemoglobin A1C, body mass index, waist circumference, and systolic and diastolic blood pressure.

METHODS

A comprehensive search for globally eligible studies was conducted on PubMed, Embase, ProQuest, CINAHL nursing & allied health source, Cochrane Library, Google Scholar, conference proceedings, and reference lists. Data were extracted using JBI standardized data extraction tool. The primary outcome variables were diabetes incidence rate, fasting blood sugar (FBS), hemoglobin A1c (HbAlc), body mass index (BMI), waist circumference (WC), systolic/diastolic blood pressure (s/d BP). Random-effects meta-analysis and sub-group analyses were conducted.

RESULTS

Nineteen interventional studies were included in the review, and ten studies were pooled in the meta-analysis (n = 16,106, mean age = 41.5 years). The incidence rate of T2D was reported in three trials, within which the risk of developing T2D was reduced by 54.0% in favor of community-based educational interventions, (RR = 0.54, 95% CI = 0.38-0.75; p < 0.001). In eleven (n = 11,587) and six (n = 6416) studies, the pooled mean differences were - 0.33 (95% CI: - 0.45 to - 0.20, p < 0.0001) and - 0.15 (95% CI: - 0.28 to - 0.03, p < 0.0001) for FBS and HbA1c levels, respectively. Positive significant effects were observed on reducing BMI [pooled mean difference = - 0.47 (95% CI: - 0.66 to - 0.28), I² = 95.7%, p < 0.0001] and WC [pooled mean difference = - 0.66 (95% CI: - 0.89 to - 0.43), I² = 97.3%, p < 0.0001]. The use of theoretical frameworks was found to provide a 48.0% change in fasting blood sugar.

CONCLUSIONS

Based on a comprehensive data collection of about 16,106 participants and reasonable analyses, we conclude that educational interventions may reduce diabetes incidence by 54.0%, particularly through reductions in fasting blood glucose, body mass index, and waist circumference. The diabetes risk parameters may favorably improve irrespective of the duration of intervention, at as low as 6 months. The application of theoretical frameworks while designing educational interventions is also encouraged.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018115877.

Establishment of the SingHealth Diabetes Registry

Purpose

To describe the inception and structure of the SingHealth Diabetes Registry (SDR) as well as the methodology used to set up the registry. The SDR was established to facilitate systematic and standardized data collection for diabetes mellitus within Singapore Health Services (SingHealth), which is an Academic Medical Center (AMC) and Singapore's largest group of healthcare institutions. The diabetes casemix and outcome variables within the registry cohort are also provided.

Materials and Methods

The SDR is built from SingHealth's electronic medical records (EMR) and clinical databases. It covers all individuals aged 18 and above with diabetes mellitus, excluding those with pre-diabetes. Cases are annually ascertained using criteria that include diagnosis codes, prescription records and laboratory test records. Data collection of casemix and outcome variables for the period 2013 to 2019 is complete.

Results

The SDR stands at 208,102 ascertained individuals, distributed across 8 healthcare sites within the AMC. The cohort is broadly reflective of the local gender and ethnic compositions but has a high proportion of older individuals with a mean age of 65.8 ± 13.7 years. Majority (>99%) have type 2 diabetes mellitus, with multiple other comorbidities (hypertension 84.1%, hyperlipidemia 86.2%, established cardiovascular disease 34.1%). At present, majority of individuals are able to meet key process indicators and 52.7% have a mean HbA1c of <7% (53 mmol/mol). Areas of potential improvement include increasing eye and foot screening rates, as well as glycemic control for the 19.5% of individuals with mean HbA1c >8% (64 mmol/mol).

Conclusion

The SDR is a large-scale, comprehensive, and representative diabetes registry that incorporates EMR data across the primary and hospital-based care continuum, in a major AMC in Singapore. The SDR has identified areas of improvement in diabetes processes and outcomes. It will support future quality assessment and improvements in diabetes care.

Dual mechanisms of a Sri Lankan traditional polyherbal mixture in the improvement of pancreatic beta cell functions and restoration of lipoprotein alterations in streptozotocin induced diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional polyherbal preparations have been utilized in Sri Lanka since ancient times and have gained a wide acceptance throughout the country. Although an extensive body of evidence supports the use of traditional herbal mixtures in the treatment of diabetes mellitus, only a few polyherbal mixtures have been subjected to systematic scientific investigations and their mechanisms for long-term glucose control remain unclear. In general, scientific evaluations of the effectiveness of antidiabetic formulations which are prescribed by traditional practitioners have received great attention, and therefore uncovering their mechanism of action would be beneficial.

AIM

The aim of the present study was to investigate the therapeutic efficacy, in terms of antidiabetic and antihyperlipidaemic activities, of a well-known traditional polyherbal mixture composed of leaves of Murraya koenigii L., -cloves of Allium sativum L., - fruits of Garcinia quaesita Pierre and seeds of Piper nigrum L. in streptozotocin induced diabetic rats.

MATERIALS AND METHODS

Equal amounts from each of the above plant parts (100 g) were mixed together and extracted into cold water, hot water (3 h, refluxed) and water-acetone (1:1) separately. Dose response study of cold water, hot water, and water-acetone extracts of the polyherbal mixture at three selected doses of 0.5 g/kg, 1.0 g/kg and 1.5 g/kg was conducted in streptozotocin (STZ) induced diabetic rats. Based on the dose response data, hot water and water-acetone extracts at the therapeutic dose of 1.0 g/kg were administered to STZ induced diabetic rats (n = 6/group) daily for 30 days in the long-term study. Glibenclamide (0.5 mg/kg) was used as the positive control. Glycaemic parameters, pancreatic β cell restoration, and lipid profile were evaluated in diabetic rats treated with the plant extract mixture. HPLC fingerprints of hot water and water-acetone extracts of the polyherbal mixture were compared with those of extracts of individual plants with the respective solvents, in the standardisation protocol.

RESULTS

The hot water and water-acetone extracts were shown to be active in the dose response study and 1.0 g/kg was selected for the long term study. Treatment with the hot water and water-acetone extracts of the polyherbal mixture and glibenclamide significantly lowered the glycated haemoglobin by 19%, 26%, and 43%, respectively, at the end of the intervention (p < 0.05). The serum insulin concentration was significantly increased (p < 0.05) upon the plant treatment, corroborating the evidence of β-cell restoration in the pancreas of H and E stained sections. Moreover, the above extracts reported an impressive restoration of lipoproteins in diabetic rats compared to the diabetic control rats. The homeostatic assessment of β-cell functions (HOMA-β) was also improved in rats treated with the hot water and water-acetone extracts of the polyherbal mixture. The HPLC fingerprints of the polyherbal mixture and the individual plants showed shifts in some peaks and formation of new peaks.

CONCLUSION

The results revealed that the aforementioned polyherbal mixture possesses potent antihyperglycaemic and antihyperlipidaemic effects with considerable restoration of pancreatic β-cells, justifying the traditional use of the mixture in diabetes associated dyslipidaemia.

Curative Effect of Catechin Isolated from Elaeagnus Umbellata Thunb. Berries for Diabetes and Related Complications in Streptozotocin-Induced Diabetic Rats Model

In this study, catechin (CTN) isolated from Elaeagnus umbellata was evaluated for in vitro antioxidant potential and inhibition of carbohydrate digestive enzymes (α-amylase and α-glucosidase). The compound was also tested for its in vivo antidiabetic potential using Sprague-Dawley rats as experimental animals. The effects of various doses of catechin in STZ (Streptozotocin) induced diabetic rats on fasting blood glucose level, body weight, lipid parameters, hepatic enzymes, and renal functions were evaluated using the reported protocols. The CTN exhibited the highest percent antioxidant for free radical scavenging activity against DPPH and ABTS free radicals, and inhibited the activity of carbohydrate digestive enzymes (with percent inhibition values: 79 ± 1.5% α-amylase and 80 ± 1.1% α-glucosidase). Administration CTN and standard glibenclamide significantly decreased the fasting blood glucose level and increased the body weight in STZ-induced diabetic rats. CTN significantly decreased the different lipid parameters, hepatic, and renal function enzyme levels along with Hb1c level in diabetic rats, while significantly increasing the high-density lipoprotein (HDL) level with values comparable to the standard glibenclamide. Further, the altered levels of glutathione and lipid peroxides of liver and kidney tissues were restored (by CTN) to levels similar to the control group. CTN significantly increased the antioxidant enzyme activities, total content of reduced glutathione, and reduced the malondialdehyde (MDA) level in rat liver and kidney tissues homogenates, and also corrected the histopathological abnormalities, suggesting its antioxidant potential.

Genome-Wide Association for HbA1c in Malay Identified Deletion on SLC4A1 that Influences HbA1c Independent of Glycemia

CONTEXT

Glycated hemoglobin A1c (HbA1c) level is used to screen and diagnose diabetes. Genetic determinants of HbA1c can vary across populations and many of the genetic variants influencing HbA1c level were specific to populations.

OBJECTIVE

To discover genetic variants associated with HbA1c level in nondiabetic Malay individuals.

DESIGN AND PARTICIPANTS

We conducted a genome-wide association study (GWAS) analysis for HbA1c using 2 Malay studies, the Singapore Malay Eye Study (SiMES, N = 1721 on GWAS array) and the Living Biobank study (N = 983 on GWAS array and whole-exome sequenced). We built a Malay-specific reference panel to impute ethnic-specific variants and validate the associations with HbA1c at ethnic-specific variants.

RESULTS

Meta-analysis of the 1000 Genomes imputed array data identified 4 loci at genome-wide significance (P < 5 × 10-8). Of the 4 loci, 3 (ADAM15, LINC02226, JUP) were novel for HbA1c associations. At the previously reported HbA1c locus ATXN7L3-G6PC3, association analysis using the exome data fine-mapped the HbA1c associations to a 27-bp deletion (rs769664228) at SLC4A1 that reduced HbA1c by 0.38 ± 0.06% (P = 3.5 × 10-10). Further imputation of this variant in SiMES confirmed the association with HbA1c at SLC4A1. We also showed that these genetic variants influence HbA1c level independent of glucose level.

CONCLUSION

We identified a deletion at SLC4A1 associated with HbA1c in Malay. The nonglycemic lowering of HbA1c at rs769664228 might cause individuals carrying this variant to be underdiagnosed for diabetes or prediabetes when HbA1c is used as the only diagnostic test for diabetes.

Diagnostic accuracy of tests for type 2 diabetes and prediabetes: A systematic review and meta-analysis

AIM

This systematic review aimed to ascertain the diagnostic accuracy (sensitivity and specificity) of screening tests for early detection of type 2 diabetes and prediabetes in previously undiagnosed adults.

METHODS

This systematic review included published studies that included one or more index tests (random and fasting tests, HbA1c) for glucose detection, with 75-gram Oral Glucose Tolerance Test (or 2-hour post load glucose) as a reference standard (PROSPERO ID CRD42018102477). Seven databases were searched electronically (from their inception up to March 9, 2020) accompanied with bibliographic and website searches. Records were manually screened and full text were selected based on inclusion and exclusion criteria. Subsequently, data extraction was done using standardized form and quality assessment of studies using QUADAS-2 tool. Meta-analysis was done using bivariate model using Stata 14.0. Optimal cut offs in terms of sensitivity and specificity for the tests were analysed using R software.

RESULTS

Of 7,151 records assessed by title and abstract, a total of 37 peer reviewed articles were included in this systematic review. The pooled sensitivity, specificity, positive (LR+) and negative likelihood ratio (LR-) for diagnosing diabetes with HbA1c (6.5%; venous sample; n = 17 studies) were 50% (95% CI: 42-59%), 97.3% (95% CI: 95.3-98.4), 18.32 (95% CI: 11.06-30.53) and 0.51 (95% CI: 0.43-0.60), respectively. However, the optimal cut-off for diagnosing diabetes in previously undiagnosed adults with HbA1c was estimated as 6.03% with pooled sensitivity of 73.9% (95% CI: 68-79.1%) and specificity of 87.2% (95% CI: 82-91%). The optimal cut-off for Fasting Plasma Glucose (FPG) was estimated as 104 milligram/dL (mg/dL) with a sensitivity of 82.3% (95% CI: 74.6-88.1%) and specificity of 89.4% (95% CI: 85.2-92.5%).

CONCLUSION

Our findings suggest that at present recommended threshold of 6.5%, HbA1c is more specific and less sensitive in diagnosing the newly detected diabetes in undiagnosed population from community settings. Lowering of thresholds for HbA1c and FPG to 6.03% and 104 mg/dL for early detection in previously undiagnosed persons for screening purposes may be considered.

Management of periodontal disease in patients with diabetes- good clinical practice guidelines: A joint statement by Indian Society of Periodontology and Research Society for the Study of Diabetes in India

There is a huge body of literature suggesting an association and a bidirectional relationship between periodontal disease and diabetes. Diabetes and periodontal diseases are both chronic diseases with a high prevalence. Dentists/periodontists, in their daily clinical practice, very often attend to diabetes patients with diverse oral health conditions and cater to their dental treatment needs. Safe and effective periodontal therapy in this population requires a broad understanding of diabetes, medical management of diabetes, and essential modifications to dental/periodontal therapy that may be required. This paper describes a joint statement put forth by the Indian Society of Periodontology and the Research Society for the Study of Diabetes in India aiming to provide expert consensus and evidence-based guidelines for optimal clinical management of periodontal conditions in diabetes patients or patients at risk for diabetes. Although this paper is not envisioned to be a comprehensive review of this topic, it intends to provide the guidelines for dental professionals and periodontists.

Prediction of type 2 diabetes mellitus using fasting plasma glucose and HbA1c levels among individuals with impaired fasting plasma glucose: a cross-sectional study in Thailand

OBJECTIVES

About 11%-30% of individuals with impaired fasting plasma glucose (IFG) have type 2 diabetes mellitus (T2DM), diagnosed by the 75 g oral glucose tolerance test (75 g OGTT). This study investigated (1) the prevalence and cut-off levels for fasting plasma glucose (FPG) and glycated haemoglobin A1c (HbA1c) in IFG individuals that most effectively predict the presence of T2DM diagnosed by a 75 g OGTT; (2) the predictors associated with T2DM; and (3) the pathophysiological characteristics of patients with IFG.

MATERIALS AND METHODS

A single-centre, cross-sectional study was conducted in a primary care setting. A standard 75 g OGTT was performed on 123 subjects with IFG. Their beta-cell function and insulin resistance were calculated through plasma glucose and insulin levels monitored during the 75 g OGTT.

RESULTS

In the IFG subjects, the prevalence of T2DM using the 2-hour postload plasma glucose (2hPG) criterion was 28.5%. Pre-diabetes and normal glucose metabolism were found in 48.7% and 22.8%, respectively, by 75 g OGTT. An HbA1c level ≥6.0% or FPG ≥5.9 mmol/L were the optimal cut-off thresholds for the prediction of the presence of T2DM. HbA1c had a sensitivity of 76.7% and specificity of 55.7% (95% CI 57.7% to 90.1% and 95% CI 43.3% to 67.6%, respectively), while FPG had a sensitivity of 85.7% and specificity of 23.9% (95% CI 69.7% to 95.2% and 95% CI 15.4% to 34.1%, respectively). The presence of metabolic syndrome, a higher HbA1c and higher FPG levels were associated with the risk of T2DM in the Thai IFG population.

CONCLUSIONS

Almost one-third of the people with IFG had T2DM diagnosed by the 2hPG criterion. HbA1c was more effective than FPG in predicting the presence of T2DM in the IFG subjects. IFG individuals with HbA1c≥6.0% or FPG≥5.9 mmol/L should be advised to undergo a 75 g OGTT to detect T2DM earlier than otherwise.

A prospective observational prevalence study of elevated HbA1c among elective surgical patients

Type 2 Diabetes Mellitus (DM) is a chronic disease with high prevalence worldwide. Using glycated haemoglobin (HbA1c) as a surrogate for potential pre-DM and DM conditions, our primary objective was to determine the HbA1c epidemiology in non-cardiac elective surgical patients in Singapore. Our secondary aim was to identify risk factors associated with elevated HbA1c. We conducted a prospective, observational single-centre study in adult patients. HbA1c screening was performed. Patient demographics and comorbidities were recorded. Patients were divided into those with HbA1C ≤ 6.0% and HbA1C ≥ 6.1%. Regression analyses were performed to identify associated factors. Subgroup analysis was performed comparing patients with HbA1C ≥ 6.1% and HbA1C ≥ 8.0%. Of the 875 patients recruited, 182 (20.8%) had HbA1c ≥ 6.1%, of which 32 (3.7%) had HbA1c ≥ 8%. HbA1C ≥ 6.1% was associated with Indian ethnicity [1.07 (1.01-1.13), p = 0.023], BMI > 27.5 [1.07 (1.02-1.11), p = 0.002], higher preoperative random serum glucose [1.03 (1.02-1.04), p < 0.001], pre-existing diagnosis of DM [1.85 (1.75-1.96), p < 0.001] and prediabetes [1.44 (1.24-1.67), p < 0.001], and peripheral vascular disease [1.30 (1.10-1.54), p = 0.002]. HbA1c ≥ 8% had an additional association with age > 60 years [0.96 (0.93-0.99), p = 0.017]. The prevalence of elevated HbA1c is high among the surgical population. Targeted preoperative HbA1c screening for at-risk elective surgical patients reduces cost, allowing focused use of healthcare resources.

Development and validation of a screening model for diabetes mellitus in patients with periodontitis in dental settings

OBJECTIVES

To identify predictors in patient profiles and to develop, internally validate, and calibrate a screening model for diabetes mellitus (DM) in patients with periodontitis in dental settings MATERIALS AND METHODS: The study included 204 adult patients with periodontitis. Patients' socio-demographic characteristics, general health status, and periodontal status were recorded as potential predictors. The diabetic status was considered the outcome, classified into no DM, prediabetes (pre-DM), or DM. Multinomial logistic regression analysis was used to develop the model. The performance and clinical values of the model were determined.

RESULTS

Seventeen percent and 47% of patients were diagnosed with DM and pre-DM, respectively. Patients' age, BMI, European background, cholesterol levels, previous periodontal treatment, percentage of the number of teeth with mobility, and with gingival recession were significantly associated with the diabetic status of the patients. The model showed a reasonable calibration and moderate to good discrimination with area under the curve (AUC) values of 0.67 to 0.80. The added predictive values for ruling in the risk of DM and pre-DM were 0.42 and 0.11, respectively, and those for ruling it out were 0.05 and 0.17, respectively.

CONCLUSIONS

Predictors in patient profiles for screening of DM and pre-DM in patients with periodontitis were identified. The calibration, discrimination, and clinical values of the model were acceptable.

CLINICAL RELEVANCE

The model may well assist clinicians in screening of diabetic status of patients with periodontitis. The model can be used as a reliable screening tool for DM and pre-DM in patients with periodontitis in dental settings.

Glycated hemoglobin (HbA1c) as diagnostic criteria for diabetes: the optimal cut-off points values for the Pakistani population; a study from second National Diabetes Survey of Pakistan (NDSP) 2016-2017

AIM

Glycated hemoglobin (HbA1c) cut-off values as diagnostic tool in diabetes and prediabetes with its concordance to oral glucose tolerance test (OGTT) in Pakistani population.

METHODOLOGY

Data for this substudy was obtained from second National Diabetes Survey of Pakistan (NDSP) 2016-2017. With this survey, 10 834 individuals were recruited and after excluding known subjects with diabetes, 6836 participants fulfilled inclusion criteria for this study. Demographic, anthropometric and biochemical parameters were obtained. OGTT was used as standard diagnostic tool to screen population and HbA1c for optimal cut-off values. Participants were categorized into normal glucose tolerance (NGT), newly diagnosed diabetes (NDD) and prediabetes.

RESULTS

Out of 6836 participants, 4690 (68.6%) had NGT, 1333 (19.5%) had prediabetes and 813 (11.9%) had NDD by OGTT criteria with median (IQR) age of 40 (31-50) years. Optimal HbA1c cut-off point for identification of diabetes and prediabetes was observed as 5.7% ((AUC (95% CI)=0.776 (0.757 to 0.795), p<0.0001)) and 5.1% ((AUC (95% CI)=0.607 (0.590 to 0.624), p<0.0001)), respectively. However, out of 68.6% NGT subjects identified through OGTT, 24.1% and 9.3% participants were found to have prediabetes and NDD, respectively by using HbA1c criteria. By using both OGTT and HbA1c criteria, only 7.9% and 7.3% were observed as prediabetes and diabetes, respectively.

CONCLUSION

Findings from second NDSP demonstrated disagreement between findings of OGTT and HbA1c as diagnostic tool for Pakistani population. As compared with international guidelines, HbA1c threshold for prediabetes and NDD were lower in this part of world. HbA1c as diagnostic tool might require ethnic or regional-based modification in cut-off points, validated by relevant community-based epidemiological surveys.

Demographic Associations of Diabetes Status by Both Fasting Plasma Glucose Concentration and Glycated Hemoglobin in a Community Survey in Galle District, Sri Lanka

Diagnostic tools used in detecting individuals with diabetes mellitus (DM) include fasting plasma glucose (FPG), glycated hemoglobin (HbA1C), and oral glucose tolerance test (OGTT). The present study was aimed to determine the demographic associations of diabetes status by both tests (FPG and HbA1C) in Galle district, Sri Lanka. 147 adults (30-60 years) who are having FPG ≥ 126 mg/dL underwent demographic evaluations and testing for HbA1C. Group 01 (diabetes status diagnosed by both tests) and group 2 (diabetes status diagnosed only by FPG) were compared using independant sample t-test and chi-square test. Logistic regression was used to study the association between the demographic factors and the diabetes status by both tests. Of the 147 study subjects, 38.1% were males, 61.9% were females, and 63.3% had a family history of diabetes among first-degree relatives (FDR). Mean age, body mass index (BMI), waist circumference (WC), FPG, and HbA1C of the participants were 48.4 ± 7.2 years, 25.1 ± 4.0 kg/m2, 88.8 ± 9.0 cm, 139.4 ± 30.1 mg/dL, and 6.4 ± 0.7%, respectively. The prevalence of diabetes based on both tests was 55.1%. There is a significant difference in mean BMI and WC while no significant differences in mean age between groups 01 and 02. No association was seen between gender and diabetes status (X 2(1) = 0.086, p=0.770), while a significant difference was observed between DM among FDR and diabetes status (X 2(1) = 33.215, p < 0.001). Significance of odds of having diabetes by both tests with rising BMI (OR = 1.97, CI 1.15-3.36, p=0.013) and DM among FDR (OR = 7.95, CI 3.54-17.88, p=0.000) was seen. We conclude rising BMI and having DM among FDR are strongly associated with diabetes status diagnosed by both tests of FPG and HbA1C in community screening.

Erythrocytosis and Performance of HbA1c in Detecting Diabetes on an Oxygen-Deficient Plateau: A Population-based Study

CONTEXT

The hemoglobin A1c (HbA1c) test is a standard test for diabetes screening and diagnosis.

OBJECTIVE

To evaluate A1c performance for diabetes screening in high-altitude polycythemia compared to a population with a high proportion of people living in an oxygen-deficient environment.

DESIGN

A population-based epidemiological survey was conducted.

SETTING

The cities Lhasa and Shigatse were selected. Volunteers were recruited through educational advertisements about diabetes.

PARTICIPANTS

A total of 1401 Tibetan adults without known diabetes.

INTERVENTIONS

Oral glucose tolerance test (OGTT), HbA1c, and complete blood cell count were performed. Hemoglobin A1c was evaluated using high-performance liquid chromatography, and serum glucose level, using the hexokinase method.

MAIN OUTCOME MEASURES

World Health Organization criteria were used to define diabetes and prediabetes. Hemoglobin A1c test performance was evaluated using receiver operating characteristic analysis.

RESULTS

The participants' mean age was 44.3 ± 15.0 years; 33.3% of the participants were men and 38.6% lived in urban areas. The prediabetes and diabetes prevalence rates were 7.5% and 3.6%, respectively. The optimal HbA1c cutoff for detecting diabetes was 46 mmol/mol (6.4%), with a sensitivity and specificity of 60.8% and 93.6%, respectively. The cutoff for detecting diabetes was 6.7% (50 mmol/mol) in subjects with high-altitude polycythemia (HAPC). The relationship between red blood cell (RBC) counts and HbA1c was significant (P < 0.001), while there was no correlation between hemoglobin (Hb) and HbA1c (P = 0.085). Multiple linear regression analysis showed that after adjusting for age and fasting serum glucose or 2-hour OGTT (OGTT2h) serum glucose, RBC count and not Hb level was an independent risk factor for HbA1c (β = 0.140, P < 0.001).

CONCLUSIONS

The optimal HbA1c cutoff for detecting diabetes was 46 mmol/mol (6.4%) in Tibet. Red blood cell count was an independent risk factor for elevated HbA1c, and HAPC may affect the predictive ability of HbA1c.

Antiphospholipid antibodies in patients with dysglycaemia: A neglected cardiovascular risk factor?

BACKGROUND

Cardiovascular disease is a serious complication in patients with dysglycaemia, defined as either type 2 diabetes or impaired glucose tolerance. Research focusing on the identification of potential markers for atherothrombotic disease in these subjects is warranted. The antiphospholipid syndrome is a common acquired prothrombotic condition, defined by a combination of thrombotic events and/or obstetric morbidity and positivity of specific antiphospholipid antibodies. Available information on antiphospholipid antibodies in dysglycaemia is scarce.

OBJECTIVE

This study investigates the association between antiphospholipid antibodies and dysglycaemia.

PATIENTS/METHODS

The PAROKRANK (periodontitis and its relation to coronary artery disease) study included 805 patients, investigated 6-10 weeks after a first myocardial infarction, and 805 matched controls. Participants without known diabetes (91%) underwent an oral glucose tolerance test. Associations between antiphospholipid antibodies (anti-cardiolipin and anti-β2 glycoprotein-I IgG, IgM and IgA) and dysglycaemia were analysed.

RESULTS

In total, 137 (9%) subjects had previously known type 2 diabetes and 371 (23%) newly diagnosed dysglycaemia. Compared with the normoglycaemic participants, those with dysglycaemia had a higher proportion with first myocardial infarction (61% vs 45%, p < 0.0001) and were more often antiphospholipid antibody IgG positive (8% vs 5%; p = 0.013). HbA1c, fasting glucose and 2-h glucose were significantly associated to antiphospholipid antibody IgG. Odds ratios (ORs) were 1.04 (95% confidence interval [CI] 1.02-1.06), 1.14 (95% CI 1.00 - 1.27) and 1.12 (95% CI 1.04 - 1.21), respectively, after adjustments for age, gender and smoking.

CONCLUSIONS

This study reports an association between antiphospholipid antibody IgG positivity and dysglycaemia. Further studies are needed to verify these findings and to investigate if antithrombotic therapy reduces vascular complications in antiphospholipid antibody positive subjects with dysglycaemia.

Cross-sectional study of the association between long working hours and pre-diabetes: 2010-2017 Korea national health and nutrition examination survey

OBJECTIVE

Long working hours have been shown to raise the risk of various health outcomes. However, epidemiological evidence has shown inconsistent result in relation to type 2 diabetes mellitus (T2DM) and the association between long working hours and pre-diabetes among non-diabetic adults remains largely unexplored. We thus aimed to investigate whether long working hours were linked with pre-diabetes as determined by glycated haemoglobin (HbA1c) level.

DESIGN

Cross-sectional survey.

PARTICIPANTS

This study included 6324 men and 4001 women without diabetes from the 2010 to 2017 Korean National Health and Nutrition Examination Survey.

PRIMARY OUTCOME MEASURES

The study outcome of interest was pre-diabetes, defined as HbA1c values 5.7% to 6.4% RESULTS: Logistic regression was performed to obtain the ORs for pre-diabetes according to categories of work hour (40 hours/week, 41 to 52 hours/week, >52 hours/week), after adjusting for relevant covariates. Of the 10 325 eligible participants, 2261 (34.4%) men and 1317 (31.0%) women had pre-diabetes. No statistically significant relationship was found for women. In men, extended working hours (>52 hours per week) was associated with an increased likelihood of pre-diabetes, after adjustment for age, educational attainment, monthly household income, lifestyle related factors, perceived stress, family history of diabetes, hypertension, hypercholesterolaemia and other covariates (adjusted OR=1.22; 95% CI 1.03 to 1.46). In the subgroup analysis by occupational categories, the association was only apparent among men in blue-collar worker groups.

CONCLUSION

Extended working hours were significantly related to pre-diabetes in men, with no statistically significant association observed for women. Further subgroup analysis by occupational categories revealed that the increased odds of pre-diabetes associated with long working hours was only apparent among male workers of blue-collar occupations and shift workers.