Relationship between glycated hemoglobin and glucose concentrations in the adult Galician population: selection of optimal glycated hemoglobin cut-off points as a diagnostic tool of diabetes mellitus

Aims/hypothesisTo analyze the relationship between glucose and glycated hemoglobin (HbA_1c) in the adult Galician population, evaluate the use of HbA_1c for the screening and diagnosis of diabetes, and calculate the diagnostic threshold required for this purpose.MethodsWe analyzed data on 2848 subjects (aged 18–85 years) drawn from a study undertaken in 2004 to assess the prevalence of diabetes in Galicia. For study purposes, diabetes was defined using the criteria recommended in 2002. Participants were classified into four glucose-based groups. The relationship between glucose and HbA_1c was described using linear regression models, generalized additive models and Spearman's correlation. Diagnostic capacity was assessed, and optimal HbA_1c cut-off points were calculated as a diabetes marker using the receiver operating characteristic curve.ResultsPrevalence of pre-diabetes, unknown diabetes and known diabetes was 20.86, 3.37 and 4.39%, respectively. The correlations between HbA_1c and fasting glucose were higher than those obtained for HbA_1c and glycemia at 2 h of the oral glucose overload (0.344 and 0.270, respectively). Taking glucose levels as the gold standard, a greater discriminatory capacity was obtained for HbA_1c (area under de cruve: 0.839, 95% confidence intervals: 0.788–0.890). Based on the study criteria, the optimal minimum and maximum HbA_1c values were 5.9% and 6.7%, respectively.Conclusions/interpretationHbA_1c did not prove superior to glycemia for diagnosis of diabetes in the adult Galician population, and cannot therefore be used to replace the oral glucose tolerance test for screening and diagnosis purposes. Indeed, determination of glucose is essential to verify the diagnosis in the majority of cases.     

A 24-Week,Prospective, Randomized,Open-Label,Treat-To-Target Pilot Study of Obese Type 2 Diabetes Patients with Severe Insulin Resistance to Assess the Addition of Exenatide on the Efficacy of U-500 Regular Insulin Plus Metformin

ObjectiveTo compare the efficacy of 500 U/mL (U-500) regular insulin + metformin with U-500 regular insulin + metformin + exenatide in improving glycemic control in patients with severely insulin-resistant type 2 diabetes mellitus (T2DM).MethodsThirty patients with T2DM and severe insulin resistance were screened, and 28 were randomized to regular insulin U-500 + metformin or the GLP-1 analog exenatide, U-500, and metformin. Glycated hemoglobin (HbA_1c) levels, body weight, and insulin doses were documented at baseline and at 3 and 6 months. The number and severity hypoglycemic episodes were noted.ResultsThere were 7 males and 7 females in each group (U-500 + metformin and U-500 + metformin + exenatide). Overall, U-500 insulin + metformin, either alone or with the addition of exenatide, resulted in a significant improvement in HbA_1c in both groups, with no significant difference between the 2 groups. There was no meaningful weight change in those utilizing exenatide. Those on U-500 insulin and metformin alone had a tendency toward some weight gain. No severe hypoglycemia occurred during the study period. Symptomatic hypoglycemia was more common in the group on exenatide, but this occurred in only 5 patients, and the clinical significance of this is uncertain. Insulin dosage changes on U-500 regular insulin were variable but tended to be lower in those subjects on exenatide.ConclusionsU-500 regular insulin + metformin is effective for the treatment of T2DM patients with severe insulin resistance. The addition of exenatide may ameliorate potential weight gain but provides no additional improvement in glycemia. (Endocr Pract. 2014;20:1143-1150)     

Patients Achieving Good Glycemic Control (HBA1c <7%) Experience A Lower Rate of Hypoglycemia With Insulin Degludec Than with Insulin Glargine: A Meta-Analysis of Phase 3A Trials

Objective: Meta-analysis to compare hypoglycemia rates of basal insulin degludec (IDeg) with insulin glargine (IGlar) in patients with diabetes achieving good glycemic control (hemoglobin A_1c [HbA_1c] <7% at end of trial).Methods: In a preplanned meta-analysis, patient data from 7 randomized, treat-to-target, 26- or 52-week trials in patients with type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM) who administered IDeg (n = 2,899) or IGlar (n = 1,431) once daily were analyzed. Using a negative binomial regression model, this meta-analysis compared hypoglycemia rates in patients achieving HbA_1c <7% at end of trial with IDeg (n = 1,347) and IGlar (n = 697).Results: In all trials, IDeg was noninferior to IGlar in HbA_1c reduction from baseline. At end of trial, 2,044 patients (T2DM, n = 1,661; T1DM, n = 383) achieved HbA_1c <7%. The overall confirmed hypoglycemia rate, defined as plasma glucose <56 mg/dL or severe hypoglycemia if requiring assistance, was significantly lower with IDeg versus IGlar (estimated rate ratio [ERR] IDeg:IGlar, 0.86; 95% confidence interval [CI], 0.76 to 0.98). The nocturnal confirmed hypoglycemia rate, defined as occurring between midnight and 6:00 am, was significantly lower with IDeg (ERR, 0.63; 95% CI, 0.52 to 0.77). In the maintenance period (16 weeks onward when average insulin dose and glycemic levels stabilized), the overall confirmed hypoglycemia rate was significantly lower (ERR, 0.79; 95% CI, 0.68 to 0.92) and the nocturnal confirmed hypoglycemia rate was significantly lower (ERR, 0.57; 95% CI, 0.45 to 0.72) with IDeg versus IGlar.Conclusion: Patients with T1DM and T2DM achieved HbA_1c <7% with significantly lower rates of overall and nocturnal confirmed hypoglycemia with IDeg versus IGlar. The lower hypoglycemia rate with IDeg was more pronounced in the maintenance period.Abbreviations: ERR = estimated rate ratio; HbA_1c = hemoglobin A_1c; IDeg = insulin degludec; IGlar = insulin glargine; NPH = Neutral Protamine Hagedorn; PG = plasma glucose; T1DM = type 1 diabetes mellitus; T2DM = type 2 diabetes mellitus     

Falsely Decreased Hba1c in A Type 2 Diabetic Patient Treated with Dapsone

ObjectiveTo discuss a case of a falsely low hemoglobin A_1c (HbA_1c) in a transplant patient treated with dapsone and its implications. HbA_1c is widely used as a measure of glycemic control in diabetic patients. With the increasing transplant population, it is important to be mindful of medications used in this population that can affect HbA_1c and to use other measures of glycemic control to guide treatment decisions.MethodsWe present details of the case and review the relevant literature.ResultsA 61-year-old patient received a liver transplant in 2012 and subsequently was noted to have a falling HbA_1c despite evidence of hyperglycemia based on fingerstick glucose and fructosamine measurements. Review of the medical records revealed that the discordance between HbA_1c and fingerstick glucose levels developed after initiation of dapsone therapy. Dapsone may lead to a falsely low HbA_1c via several mechanisms. Upon cessation of dapsone therapy, the patient’s HbA_1c returned to pre-dapsone levels.ConclusionIt is important to be aware of medications commonly used in transplant patients that may lead to a falsely low HbA_1c level so that incorrect treatment decisions are not made. Fructosamine correlates with HbA_1c and can be used as a measure of glycemic control in transplant patients when HbA_1c cannot be used. (Endocr Pract. 2014;20:e229-e232)     

Mass spectrometry based characterization of Hb Beckman variant in a falsely elevated HbA1c sample

Glycated hemoglobin (HbA_1c) is a ‘gold standard’ biomarker for assessing the glycemic index of an individual. HbA_1c is formed due to nonenzymatic glycosylation at N-terminal valine residue of the β-globin chain. Cation exchange based high performance liquid chromatography (CE–HPLC) is mostly used to quantify HbA_1c in blood sample. A few genetic variants of hemoglobin and post-translationally modified variants of hemoglobin interfere with CE–HPLC-based quantification, resulting in its false positive estimation. Using mass spectrometry, we analyzed a blood sample with abnormally high HbA_1c (52.1%) in the CE–HPLC method. The observed HbA_1c did not corroborate the blood glucose level of the patient. A mass spectrometry based bottom up proteomics approach, intact globin chain mass analysis, and chemical modification of the proteolytic peptides identified the presence of Hb Beckman, a genetic variant of hemoglobin, in the experimental sample. A similar surface area to charge ratio between HbA_1c and Hb Beckman might have resulted in the coelution of the variant with HbA_1c in CE–HPLC. Therefore, in the screening of diabetes mellitus through the estimation of HbA_1c, it is important to look for genetic variants of hemoglobin in samples that show abnormally high glycemic index, and HbA_1c must be estimated using an alternative method.     

Sputum Glucose and Glycemic Control in Cystic Fibrosis-Related Diabetes: A Cross-Sectional Study

Cystic fibrosis-related diabetes affects up to half of cystic fibrosis patients and is associated with increased mortality and more frequent pulmonary exacerbations. However, it is unclear to what degree good glycemic control might mitigate these risks and clinical outcomes have not previously been studied in relation to glucose from the lower airways, the site of infection and CF disease progression. We initially hypothesized that diabetic cystic fibrosis patients with glycosylated hemoglobin (HbA_1c) > 6.5% have worse pulmonary function, longer and more frequent exacerbations and also higher sputum glucose levels than patients with HbA_1c ≤ 6.5% or cystic fibrosis patients without diabetes. To test this, we analyzed spontaneously expectorated sputum samples from 88 cystic fibrosis patients. The median sputum glucose concentration was 0.70 mM (mean, 4.75 mM; range, 0-64.6 mM). Sputum glucose was not correlated with age, sex, body mass index, diabetes diagnosis, glycemic control, exacerbation frequency or length, or pulmonary function. Surprisingly, sputum glucose was highest in subjects with normal glucose tolerance, suggesting the dynamics of glycemic control, sputum glucose and pulmonary infections are more complex than previously thought. Two-year mean HbA_1c was positively correlated with the length of exacerbation admission (p < 0.01), and negatively correlated with measures of pulmonary function (p < 0.01). While total number of hospitalizations for exacerbations were not significantly different, subjects with an HbA_1c > 6.5% were hospitalized on average 6 days longer than those with HbA_1c ≤ 6.5% (p < 0.01). Current clinical care guidelines for cystic fibrosis-related diabetes target HbA_1c ≤ 7% to limit long-term microvascular damage, but more stringent glycemic control (HbA_1c ≤ 6.5%) may further reduce the short-term pulmonary complications.     

Fructosamine Is a Useful Indicator of Hyperglycaemia and Glucose Control in Clinical and Epidemiological Studies – Cross-Sectional and Longitudinal Experience from the AMORIS Cohort

Context

Fructosamine is a glycemic biomarker which may be useful for indication and control of diabetes respectively.

Objective

The objective of the study was to evaluate fructosamine as an indicator of hyperglycaemia and glucose control in subjects with diabetes.

Design, Setting & Patients

From the AMORIS cohort, subjects with serum glucose, fructosamine and HbA_1c from the same examination were studied cross-sectionally and longitudinally (n = 10,987; 5,590 overnight-fasting). The guidelines of the American Diabetes Association were followed for classification of prediabetes and diabetes. Separate analyses were performed in patients with a newly detected or a known diagnosis of type 1 or type 2 diabetes respectively.

Results

All three biomarkers were strongly correlated. With regard to the association between fructosamine and HbA_1c Pearson linear correlation coefficients in the range of 0.67–0.75 were observed in fasting and non-fasting subjects with type 1 or type 2 diabetes. Analyses of glucose control in fasting patients with type 2 diabetes having all three biomarkers measured at three separate occasions within on average 290 days of the index examination showed similar trends over time for glucose, fructosamine and HbA_1c. Discrimination of subjects with and without diabetes across the range of fructosamine levels was good (area under curve (AUC) 0.91–0.95) and a fructosamine level of 2.5 mmol/L classified subjects to diabetes with a sensitivity of 61% and a specificity of 97%.

Conclusions

Fructosamine is closely associated with HbA_1c and glucose respectively and may be a useful biomarker of hyperglycaemia and glucose control in clinical and epidemiological studies.     

Assessment of AACE/ACE Recommendations for Initial Dual Antihyperglycemic Therapy Using the Fixed-Dose Combination of Sitagliptin and Metformin Versus Metformin

ObjectiveThe American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) diabetes algorithm recommends a stratified approach to initial therapy to achieve a glycated hemoglobin (HbA_1c) goal of <6.5% in patients with type 2 diabetes mellitus (T2DM) who have inadequate glycemic control. Data from a double-blind study in drug-naïve T2DM patients comparing initial monotherapy with metformin (MET) with initial dual therapy with a fixed-dose combination of sitagliptin and MET (SITA/MET FDC) was used to determine AACE/ACE HbA_1c goal attainment in these treatment groups.MethodsA total of 1,250 patients (mean baseline HbA_1c = 9.9%) were randomized 1:1 to SITA/MET FDC 50/500 mg twice daily (b.i.d.) or MET 500 mg b.i.d. for 18 weeks. SITA/MET FDC and MET were uptitrated over 4 weeks to 50/1,000 mg b.i.d. and 1,000 mg b.i.d., respectively.ResultsAt week 18, a higher percentage of patients receiving SITA/MET FDC had HbA_1c levels <6.5% and <7% than those receiving MET alone within each of the 3 AACE/ACE HbA_1c categories (6.5-7.5%, >7.5-9.0%, and >9.0%). Of patients with a baseline HbA_1c >7.5-9.0% who initiated SITA/MET FDC, 48.6% achieved an HbA_1c <6.5% at week 18 compared with 23.1% of patients who initiated MET monotherapy (P<.001). In patients with a baseline HbA >9.0%, 24.0% on SITA/MET FDC achieved an HbA_1c <6.5% compared with 12.8% on MET alone (P<.001).ConclusionIn T2DM patients with a baseline HbA_1c >7.5-9.0%, substantially more achieved the HbA_1c goal of <6.5% with initial dual therapy (SITA/MET FDC) than with initial monotherapy (MET), which is in agreement with the AACE/ACE diabetes algorithm.(Endocr Pract. 2013;19:751-757)     

Association of HbA1c values with mortality and cardiovascular events in diabetic dialysis patients. The INVOR study and review of the literature

Background

Improved glycemic control reduces complications in patients with diabetes mellitus (DM). However, it is discussed controversially whether patients with diabetes mellitus and end-stage renal disease benefit from strict glycemic control.

Methods

We followed 78 patients with DM initiating dialysis treatment of the region of Vorarlberg in a prospective cohort study applying a time-dependent Cox regression analysis using all measured laboratory values for up to more than seven years. This resulted in 880 HbA_1c measurements (with one measurement every 3.16 patient months on average) during the entire observation period. Non-linear P-splines were used to allow flexible modeling of the association with mortality and cardiovascular disease (CVD) events.

Results

We observed a decreased mortality risk with increasing HbA_1c values (HR = 0.72 per 1% increase, p = 0.024). Adjustment for age and sex and additional adjustment for other CVD risk factors only slightly attenuated the association (HR = 0.71, p = 0.044). A non-linear P-spline showed that the association did not follow a fully linear pattern with a highly significant non-linear component (p = 0.001) with an increased risk of all-cause mortality for HbA_1c values up to 6–7%. Causes of death were associated with HbA_1c values. The risk for CVD events, however, increased with increasing HbA_1c values (HR = 1.24 per 1% increase, p = 0.048) but vanished after extended adjustments.

Conclusions

This study considered the entire information collected on HbA_1c over a period of more than seven years. Besides the methodological advantages our data indicate a significant inverse association between HbA_1c levels and all-cause mortality. However, for CVD events no significant association could be found.     

The Relationship Between Breakfast Skipping,Chronotype, and Glycemic Control in Type 2 Diabetes

Breakfast skipping is associated with obesity and an increased risk of type 2 diabetes. Later chronotypes, individuals who have a preference for later bed and wake times, often skip breakfast. The aim of the study was to explore the relationships among breakfast skipping, chronotype, and glycemic control in type 2 diabetes patients. We collected sleep timing and 24-h dietary recall from 194 non-shift-working type 2 diabetes patients who were being followed in outpatient clinics. Mid-sleep time on free days (MSF) was used as an indicator of chronotype. Hemoglobin A1C (HbA_1C) values were obtained from medical records. Hierarchical linear regression analyses controlling for demographic, sleep, and dietary variables were computed to determine whether breakfast skipping was associated with HbA_1C. Additional regression analyses were performed to test if this association was mediated by chronotype. There were 22 participants (11.3%) who self-reported missing breakfast. Breakfast skippers had significantly higher HbA_1C levels, higher body mass indices (BMI), and later MSF than breakfast eaters. Breakfast skipping was significantly associated with higher HbA_1C values (B?=?0.108, p?=?0.01), even after adjusting for age, sex, race, BMI, number of diabetes complications, insulin use, depressive symptoms, perceived sleep debt, and percentage of daily caloric intake at dinner. The relationship between breakfast skipping and HbA_1C was partially mediated by chronotype. In summary, breakfast skipping is associated with a later chronotype. Later chronotype and breakfast skipping both contribute to poorer glycemic control, as indicated by higher HbA_1C levels. Future studies are needed to confirm these findings and determine whether behavioral interventions targeting breakfast eating or sleep timing may improve glycemic control in patients with type 2 diabetes.     

HbA1c Alone Is a Poor Indicator of Cardiometabolic Risk in Middle-Aged Subjects with Pre-Diabetes but Is Suitable for Type 2 Diabetes Diagnosis: A Cross-Sectional Study

Objectives

Glycated haemoglobin A_1c (HbA_1c) measurement is recommended as an alternative to fasting plasma glucose (FPG) for the diagnosis of pre-diabetes and type 2 diabetes. However, evidence suggests discordance between HbA_1c and FPG. In this study we examine a range of metabolic risk features, pro-inflammatory cytokines, acute-phase response proteins, coagulation factors and white blood cell counts to determine which assay more accurately identifies individuals at increased cardiometabolic risk.

Materials and Methods

This was a cross-sectional study involving a random sample of 2,047 men and women aged 46-73 years. Binary and multinomial logistic regression were employed to examine risk feature associations with pre-diabetes [either HbA_1c levels 5.7-6.4% (39-46 mmol/mol) or impaired FPG levels 5.6-6.9 mmol/l] and type 2 diabetes [either HbA_1c levels >6.5% (>48 mmol/mol) or FPG levels >7.0 mmol/l]. Receiver operating characteristic curve analysis was used to evaluate the ability of HbA_1c to discriminate pre-diabetes and diabetes defined by FPG.

Results

Stronger associations with diabetes-related phenotypes were observed in pre-diabetic subjects diagnosed by FPG compared to those detected by HbA_1c. Individuals with type 2 diabetes exhibited cardiometabolic profiles that were broadly similar according to diagnosis by either assay. Pre-diabetic participants classified by both assays displayed a more pro-inflammatory, pro-atherogenic, hypertensive and insulin resistant profile. Odds ratios of having three or more metabolic syndrome features were also noticeably increased (OR: 4.0, 95% CI: 2.8-5.8) when compared to subjects diagnosed by either HbA_1c (OR: 1.4, 95% CI: 1.2-1.8) or FPG (OR: 3.0, 95% CI: 1.7-5.1) separately.

Conclusions

In middle-aged Caucasian-Europeans, HbA_1c alone is a poor indicator of cardiometabolic risk but is suitable for diagnosing diabetes. Combined use of HbA_1c and FPG may be of additional benefit for detecting individuals at highest odds of type 2 diabetes development.     

Patient-Led Versus Physician-Led Titration of Insulin Glargine in Patients with Uncontrolled Type 2 Diabetes: A Randomized Multinational Atlas Study

ObjectiveSelf-adjustment of insulin dose is commonly practiced in Western patients with type 2 diabetes but is usually not performed in Asian patients. This multinational, 24-week, randomized study compared patient-led with physician-led titration of once-daily insulin glargine in Asian patients with uncontrolled type 2 diabetes who were on 2 oral glucose-lowering agents.MethodsPatient-led (n = 275) or physician-led (n = 277) subjects followed the same dose-titration algorithm guided by self-monitored fasting blood glucose (FBG; target, 110 mg/dL [6.1 mmol/L]). The primary endpoint was change in mean glycated hemoglobin (HbA_1c) at week 24 in the patient-led versus physician-led titration groups.ResultsPatient-led titration resulted in a significantly higher drop in HbA_1c value at 24 weeks when compared with physician-led titration (− 1.40% vs. − 1.25%; mean difference, − 0.15; 95% confidence interval, − 0.29 to 0.00; P = .043). Mean decrease in FBG was greatest in the patient-led group (− 2.85 mmol/L vs. − 2.48 mmol/L; P = .001). The improvements in HbA_1c and FBG were consistent across countries, with similar improvements in treatment satisfaction in both groups. Mean daily insulin dose was higher in the patient-led group (28.9 units vs. 22.2 units; P < .001). Target HbA_1c of < 7.0% without severe hypoglycemia was achieved in 40.0% and 32.9% in the patient-led and physician-led groups, respectively (P = .086). Severe hypoglycemia was not different in the 2 groups (0.7%), with an increase in nocturnal and symptomatic hypoglycemia in the patient-led arm.ConclusionPatient-led insulin glargine titration achieved near-target blood glucose levels in Asian patients with uncontrolled type 2 diabetes who were on 2 oral glucose-lowering drugs, demonstrating that Asian patients can self-uptitrate insulin dose effectively when guided. (Endocr Pract. 2015;21:143-157)     

Glycemia Management and Cardiovascular Risk in Type 2 Diabetes: An Evolving Perspective

ObjectiveTo review recent glycemia trials focused on reducing cardiovascular disease (CVD) risk in patients with type 2 diabetes and to describe how the results of these studies have altered our approach to the management of glycemia in patients with diabetes.MethodsResults of some of the previous as well as recent trials, including the Action to Control Cardiovascular Risk in Diabetes (ACCORD), Action in Diabetes and Vascular Disease (ADVANCE), and Veterans Affairs Diabetes Trial (VADT), are reviewed.ResultsThe results demonstrate that the establishment of glycemia (hemoglobin A1c) goals in patients with type 2 diabetes aimed at reducing CVD events is complex, should be highly individualized, and should probably be varied depending on the duration of diabetes as well as the presence or absence of CVD and microvascular complications.ConclusionResults of the ACCORD, ADVANCE, and VADT studies have considerably increased our knowledge and refined our approach to establishing glycemia goals in patients with type 2 diabetes. In patients with recently recognized diabetes with no prior CVD events, glycemic control to normal or near-normal levels appears to be effective in preventing CVD events and mortality. In patients with established diabetes (8 to 10 or more years) and recognized CVD, however, glycemic control to normal or near-normal levels does not reduce the risk of further CVD events or mortality. Importantly, strict control of all known risk factors for CVD and microvascular complications by aggressive management of hypertension, dyslipidemia, and glycemia, use of aspirin, and cessation of smoking in patients with type 2 diabetes has proved to be highly beneficial. (Endocr Pract. 2008;14:639-643)     

Glycemic Control After Hospital Discharge in Insulin-Treated Type 2 Diabetes: A Randomized Pilot Study of Daily Remote Glucose Monitoring

ObjectiveLittle is known about glycemic control in type 2 diabetes patients treated with insulin in the high-risk period between hospital discharge and follow-up. We sought to assess the impact of remote glucose monitoring on postdischarge glycemic control and insulin titration.MethodsWe randomly assigned 28 hospitalized type 2 diabetes patients who were discharged home on insulin therapy to routine specialty care (RSC) or RSC with daily remote glucose monitoring (RGM). We compared the primary outcome of mean blood glucose and exploratory outcomes of hypoglycemia/hyperglycemia rates, change in hemoglobin A_1c and glycated albumin, and insulin titration frequency between groups.ResultsMean blood glucose was not significantly different between the treatment arms (144 ± 34 mg/dL in the RSC group and 172 ± 41 mg/dL in the RGM group; not significant), nor were there significant differences in any of the other measures of glycemia during the month after discharge. Hypoglycemia (glucometer reading < 60 mg/dL) was common, occurring in 46% of subjects, with no difference between groups. In as-treated analysis, insulin dose adjustments (29% with an increase and 43% with decrease in insulin dose) occurred more frequently in the patients who used RGM (average of 2.8 vs. 1.2 dose adjustments; P = .03).ConclusionIn this pilot trial in insulin-treated type 2 diabetes, RGM did not affect glycemic control after hospital discharge; however, the high rate of hypoglycemia in the postdischarge transition period and the higher frequency of insulin titration in patients who used RGM suggest a safety role for such monitoring in the transition from hospital to home. (Endocr Pract. 2015;21:115-121)     

Efficacy and Safety of Linagliptin in Black/African American Patients with Type 2 Diabetes: A 6-Month,Randomized, Double-Blind,Placebo-Controlled Study

ObjectiveAlthough black/African American individuals are disproportionately affected by type 2 diabetes, there is scant clinical trial information available on antidiabetes therapies in this group. We compared linagliptin with placebo in black/African American adults who were treatment-naïve or receiving one oral antidiabetes drug.MethodsOf 226 patients randomized to 24 weeks’ linagliptin 5 mg/day or placebo, 208 had baseline and at least one on-treatment glycated hemoglobin (HbA_1c) measurement. Mean baseline HbA_1c was 8.6% in the linagliptin group (n = 98) and 8.68% in the placebo group (n = 110). The primary outcome was change in HbA_1c from baseline to week 24.ResultsBy week 24, mean HbA_1c changes were − 0.84% with linagliptin and − 0.25% with placebo (treatment difference, − 0.58%; P < .001), and more patients in the linagliptin group achieved HbA_1c < 7.0% (26.8% vs. 8.3%; P = .001) or an HbA_1c reduction ≥ 0.5% (54.1% vs. 30.0%; P < .001). Mean weight loss was − 1.1 kg in both groups. During the treatment period, 8 of 98 linagliptingroup patients and 17 of 110 placebo-group patients required rescue therapy (odds ratio, 0.5; P = .14). For postprandial glucose, values were available for few patients (11 placebo, 10 linagliptin), and thus the between-group difference was associated with wide confidence intervals (CIs) (difference, − 1.97 mg/dL; 95% CI, − 53.80 to 49.86; P = .94). In the overall study population, a similar proportion of patients in both groups had adverse events (58.5% vs. 61.7%); most events were mild or moderate and considered unrelated to study drug. Investigator-defined hypoglycemia was rare (3 linagliptin-group patients and 1 placebogroup patient), with no severe events (requiring external assistance).ConclusionThis study confirms that linagliptin is efficacious and well tolerated in black/African American patients with type 2 diabetes. (Endocr Pract. 2014;20: 412-420)     

Treatment of Type 2 Diabetes Mellitus With Orally Administered Agents: Advances in Combination Therapy

ObjectiveTo discuss the effects and clinical benefit provided by combining various orally administered antidiabetic drugs (OADs) for the treatment of type 2 diabetes and to examine the advantages of single-tablet combinations with respect to targeting hyperglycemia and adherence.MethodsA review of randomized controlled trials that studied OAD combinations for the treatment of type 2 diabetes was conducted by using search terms in PubMed.ResultsReported data have documented that OAD combination therapies have additional benefits over monotherapy in terms of glycemic efficacy. Results from randomized controlled trials on a range of OAD combinations have demonstrated differences in safety and efficacy. The use of single-tablet OAD combinations has been shown to improve adherence in patients.ConclusionThe development of single-tablet OAD combinations that can address all aspects of glycemia with a favorable tolerability profile has the potential to help patients manage their glycemic control more effectively and to minimize the risk of long-term diabetes-related complications. In addition, single-tablet combinations of agents offer improved convenience for patients as well as potential cost benefits. Thus, they represent an important treatment option for type 2 diabetes. (Endocr Pract. 2009;15:750-762)     

Gender differences in self-rated health,quality of life,quality of care,and metabolic control in patients with diabetes

Background: Because the projected increase in the number of diabetic patients is expected to strain the capabilities of health care providers worldwide, we are challenged to find ways of reducing the burden of diabetes. Maintaining and improving health-related quality of life (QoL) for diabetic patients may be viewed as public health goals.Objective: The aim of this cross-sectional study was to compare different aspects of health, QoL, and quality of care (QoC) between men and women with diabetes as a basis for planning and managing diabees care.Methods: All patients in 2 age groups (aged 20–30 years [younger age group] and aged 50–60 years [middle-aged group]) who were registered with the Department of Endocrinology, Metabolism, and Diabetes at Karolinska University Hospital, Stockholm, Sweden, in October 2004, were recruited for a survey. Questions were included about self-rated health (SRH), QoL, QoC, diabetes-related worries, occupational status, physical activity level, living arrangements, and educational background. Glycosylated hemoglobin (HbA_1c) values were obtained from medical records.Results: Of the 223 eligible patients (109 men, 114 women) in the younger age group, 49 men and 74 women responded to the questionnaire; of the 300 eligible patients (170 men, 130 women) in the middle-aged group, 120 men and 93 women responded. Middle-aged women rated their mental well-being and QoL as worse compared with men (P < 0.001 and P < 0.05, respectively). In both age groups, women reported more diabetes-related worries and less ability to cope (P < 0.05 for the younger age group and P < 0.001 for the middle-aged group for both variables), thus the differences were more marked for middleaged women. Although there were no gender differences in metabolic control, middle-aged women reported less satisfaction with diabetes care (P < 0.001). Higher HbA_1c was related to worse SRH in both men and women when analyzing the age groups together (P < 0.05). This association was most prominent in young women, in whom having more diabetes-related worries was also related to higher HbA_1c (P < 0.01).Conclusion: In this study, women with diabetes appeared to have worse QoL and mental well-being compared with men with diabetes. Therefore, identifying strategies to improve SRH and QoL among diabetic patients, especially among women, is of great importance.     

Trace elements,oxidative stress and glycemic control in young people with type 1 diabetes mellitus

Trace elements and oxidative stress are associated with glycemic control and diabetic complications in type 1 diabetes mellitus. In this study, we analyzed the levels of serum copper, zinc, superoxide dismutase (SOD) activity, and malondialdehyde (MDA) and urinary MDA and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in 33 type 1 diabetic patients with optimal and suboptimal glycemic control (HbA_1C < 9.0%) and 40 patients with poor glycemic control (HbA_1C ≥ 9%) and 27 age- and sex-matched non-diabetic controls to evaluate the differences between these markers in different glycemic control states. Diabetic patients, especially poor-glycemic-control subjects (HbA_1C ≥ 9%), exhibited significantly lower levels of serum zinc and increased levels of serum copper (and, therefore, increased serum copper-to-zinc ratios), serum SOD, blood MDA, and urinary MDA and 8-OHdG, relative to non-diabetic subjects. Furthermore, significant correlations existed in these patients between the serum copper, serum copper-to-zinc ratio, and urinary MDA (all p < 0.001) and the levels of urinary 8-OHdG (p = 0.007) and HbA_1C. Our results suggest that high serum copper levels and oxidative stress correlate with glycemic control. Therefore, strict glycemic control, decreased oxidative stress, and a lower copper concentration might prevent diabetic complications in patients with type 1 diabetes mellitus.     

Markedly Low Hemoglobin A1c in a Patient with an Unusual Presentation of ß-Thalassemia Minor

ObjectiveTo describe very low hemoglobin A_1c levels in a patient with type 2 diabetes mellitus and an unusual presentation of β-thalassemia minor.MethodsWe present the clinical and laboratory findings of the study patient.ResultsA 64-year-old African American man with type 2 diabetes mellitus was referred to the endocrinology clinic with a hemoglobin A_1c level of 1.6% despite elevated blood glucose concentrations. A red blood cell survival study with chromium-51 revealed that he had a reduced erythrocyte life span less than 25% of normal. He also had a markedly elevated reticulocyte count ranging from 236 to 534 x 10³/μL (reference range, 25-75 x 103/μL). The laboratory findings, which are not characteristic of ß-thalassemia minor, could be the cause of the markedly low hemoglobin A_1c in this patient.ConclusionsAlthough rare, when associated with marked erythrocyte turnover, β-thalassemia minor can lead to a severe reduction in HbA_1c levels. In this scenario, glycemic control is best assessed by measuring fructosamine. (Endocr Pract. 2010;16:89-92)