Cardiovascular autonomic neuropathy in type 2 diabetes mellitus patients with peripheral artery disease

OBJECTIVE

To evaluate possible associations between cardiovascular autonomic dysfunction and peripheral artery disease (PAD) in patients with type 2 diabetes mellitus.

RESEARCH DESIGN AND METHODS

In this cross-sectional study, 67 patients with type 2 diabetes were included. PAD was identified by Doppler ultrasonography: systolic ankle-brachial pressure index <0.9. Cardiovascular autonomic function, besides five conventional cardiovascular autonomic function tests, was assessed by heart rate variability (HRV; 24-h ambulatory ECG recording) in time and frequency domains (spectral analyses) and three dimensional return maps. Power spectral analyses (PSA) were quantified in low frequency (LF), high frequency (HF), and very low frequency.

RESULTS

Patients with PAD (n = 30) had longer diabetes duration, higher systolic blood pressure (BP), waist-to-hip ratio, HbA1C test, and urinary albumin excretion (UAE) than patients without PAD. Most HRV indices in time domain were lower in patients with than without PAD. These patients also had lower PSA indices (LF=0.19±0.07 vs. 0.29±0.11 n.u.; LF/HF ratio=1.98±0.9 vs. 3.35±1.83; P< 0.001) and indices of sympathetic (three-dimensional return map: P1-night 61.7±9.4 vs. 66.8±9.7; P=0.04) and vagal (24-h P2 54.5±15.2 vs. 62.7±2.9; P< 0.02) activities (arbitrary units) than patients without PAD. Multivariate logistic regression analyses, adjusted for systolic BP, DM duration, HbA1C test, and UAE, confirmed the associations between impaired autonomic modulation and PAD, except for P1 index.

CONCLUSION

In conclusion, patients with type 2 diabetes with PAD had lower HRV indices than patients without PAD, reflecting a dysfunction of cardiovascular autonomic modulation.

Evidence-based clinical use of insulin premixtures

Brazil is expected to have 19.6 million patients with diabetes by the year 2030. A key concept in the treatment of type 2 diabetes mellitus (T2DM) is establishing individualized glycemic goals based on each patient's clinical characteristics, which impact the choice of antihyperglycemic therapy. Targets for glycemic control, including fasting blood glucose, postprandial blood glucose, and glycated hemoglobin (A1C), are often not reached solely with antihyperglycemic therapy, and insulin therapy is often required. Basal insulin is considered an initial strategy; however, premixed insulins are convenient and are equally or more effective, especially for patients who require both basal and prandial control but desire a more simplified strategy involving fewer daily injections than a basal-bolus regimen. Most physicians are reluctant to transition patients to insulin treatment due to inappropriate assumptions and insufficient information. We conducted a nonsystematic review in PubMed and identified the most relevant and recently published articles that compared the use of premixed insulin versus basal insulin analogues used alone or in combination with rapid-acting insulin analogues before meals in patients with T2DM. These studies suggest that premixed insulin analogues are equally or more effective in reducing A1C compared to basal insulin analogues alone in spite of the small increase in the risk of nonsevere hypoglycemic events and nonclinically significant weight gain. Premixed insulin analogues can be used in insulin-naïve patients, in patients already on basal insulin therapy, and those using basal-bolus therapy who are noncompliant with blood glucose self-monitoring and titration of multiple insulin doses. We additionally provide practical aspects related to titration for the specific premixed insulin analogue formulations commercially available in Brazil.

Effect of different types of self-management education in patients with diabetes

Education plays an important role in diabetes mellitus (DM) treatment, as it enables patients to manage their disease. There is a wide range of tested educational interventions, and, to date, no universal model that can be standardized and recognized as effective for all individuals with the disease has been defined. This article aims to review the effect of different types of educational interventions for self-management of glycemic control in patients with DM type 2, in addition to define general recommendations for this treatment strategy.

Association study of sorbitol dehydrogenase -888G>C polymorphism with type 2 diabetic retinopathy in Caucasian-Brazilians

Diabetic retinopathy (DR) is a common chronic complication of diabetes and remains the leading cause of blindness in working-aged people. Hyperglycemia increases glucose flux through the polyol pathway, in which aldose reductase converts glucose into intracellular sorbitol, which is subsequently converted to fructose by sorbitol dehydrogenase (SDH). The accelerated polyol pathway triggers a cascade of events leading to retinal vascular endothelial dysfunction and the eventual development of DR. Polymorphisms in the gene encoding aldose reductase have been consistently associated with DR. However, only two studies have analyzed the relationship between polymorphisms in the gene encoding SDH (SORD) and DR. In this case-control study, we investigated whether the -888G > C polymorphism (rs3759890) in the SORD gene is associated with the presence or severity of DR in 446 Caucasian-Brazilians with type 2 diabetes (241 subjects with and 205 subjects without DR). The -888G > C polymorphism was also examined in 105 healthy Caucasian blood donors, and the genotyping of this polymorphism was carried out by real-time PCR. The genotype and allele frequencies of the -888G > C polymorphism in patients with type 2 diabetes were similar to those of blood donors (G allele frequency = 0.16 in both groups of subjects). Similarly, the genotype and allele frequencies in patients with DR or the proliferative form of DR were similar to those of patients without this complication (P > 0.05 for all comparisons). Thus, our findings suggest that the -888G > C polymorphism in the SORD gene is not involved in the pathogenesis of DR in type 2 diabetes.

The role of the uncoupling protein 1 (UCP1) on the development of obesity and type 2 diabetes mellitus

It is well established that genetic factors play an important role in the development of both type 2 diabetes mellitus (DM2) and obesity, and that genetically susceptible subjects can develop these metabolic diseases after being exposed to environmental risk factors. Therefore, great efforts have been made to identify genes associated with DM2 and/or obesity. Uncoupling protein 1 (UCP1) is mainly expressed in brown adipose tissue, and acts in thermogenesis, regulation of energy expenditure, and protection against oxidative stress. All these mechanisms are associated with the pathogenesis of DM2 and obesity. Hence, UCP1 is a candidate gene for the development of these disorders. Indeed, several studies have reported that polymorphisms -3826A/G, -1766A/G and -112A/C in the promoter region, Ala64Thr in exon 2 and Met299Leu in exon 5 of UCP1 gene are possibly associated with obesity and/or DM2. However, results are still controversial in different populations. Thus, the aim of this study was to review the role of UCP1 in the development of these metabolic diseases.

Impact of adjuvant chemotherapy in completely resected stage IIIA non-small cell lung cancer

AIM

Outcome of patients with locally advanced non-small-cell lung cancer (NCSLC) is generally poor, with five-year survival rate of only 23%, when patients are treated with surgery only. The presentation of positive adjuvant therapy trials in NSCLC has changed clinical practice, doubling the number of patients with completely resected NSCLC referred for adjuvant chemotherapy since 2004. Furthermore, few large studies described a large number of stage III patients in non-Asiatic patients and they showed controversial results about survival in completely resected stage IIIA NSCLC. The objective of this study was to evaluate the impact of adjuvant chemotherapy in completely resected stage IIIA NCSLC, administered on a routine basis, outside clinical trials.

METHODS

This is a retrospective study of patients with stage IIIA NCSLC treated between 1990 and 2008, and included in a continuous, consecutive database. Inclusion criteria were: age >18 years, complete surgical resection, and pathologically confirmed as stage IIIA. The following clinical data were obtained: age, gender, performance status, histological type, chemotherapy regimens, status at last follow-up and hospital where the treatment occurred. Kaplan-Meier's method was used to determine actuarial survival. Differences in survival were determined by Breslow and log rank analyses.

RESULTS

According to these inclusion criteria, 415 patients were considered for the present study. The median follow-up time of all patients was 38.2 months. The adjuvant chemotherapeutic treatment affected survival significantly (P <0.001). Also the type of chemotherapeutic treatment affected survival (P ≤0.001).

CONCLUSION

Cisplatin-based adjuvant chemotherapy was beneficial in patients who had a completed resected stage IIIA carcinoma.

A novel model-based meta-analysis to indirectly estimate the comparative efficacy of two medications: an example using DPP-4 inhibitors, sitagliptin and linagliptin, in treatment of type 2 diabetes mellitus

OBJECTIVES

To develop a longitudinal statistical model to indirectly estimate the comparative efficacies of two drugs, using model-based meta-analysis (MBMA). Comparison of two oral dipeptidyl peptidase (DPP)-4 inhibitors, sitagliptin and linagliptin, for type 2 diabetes mellitus (T2DM) treatment was used as an example.

DESIGN

Systematic review with MBMA.

DATA SOURCES

MEDLINE, EMBASE, http://www.ClinicalTrials.gov, Cochrane review of DPP-4 inhibitors for T2DM, sitagliptin trials on Food and Drug Administration website to December 2011 and linagliptin data from the manufacturer.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Double-blind, randomised controlled clinical trials, ≥12 weeks' duration, that analysed sitagliptin or linagliptin efficacies as changes in glycated haemoglobin (HbA1c) levels, in adults with T2DM and HbA1c >7%, irrespective of background medication. MODEL DEVELOPMENT AND APPLICATION: A Bayesian model was fitted (Markov Chain Monte Carlo method). The final model described HbA1c levels as function of time, dose, baseline HbA1c, washout status/duration and ethnicity. Other covariates showed no major impact on model parameters and were not included. For the indirect comparison, a population of 1000 patients was simulated from the model with a racial composition reflecting the average racial distribution of the linagliptin trials, and baseline HbA1c of 8%.

RESULTS

The model was developed using longitudinal data from 11 234 patients (10 linagliptin, 15 sitagliptin trials), and assessed by internal evaluation techniques, demonstrating that the model adequately described the observations. Simulations showed both linagliptin 5 mg and sitagliptin 100 mg reduced HbA1c by 0.81% (placebo-adjusted) at week 24. Credible intervals for participants without washout were -0.88 to -0.75 (linagliptin) and -0.89 to -0.73 (sitagliptin), and for those with washout, -0.91 to -0.76 (linagliptin) and -0.91 to -0.75 (sitagliptin).

CONCLUSIONS

This study demonstrates the use of longitudinal MBMA in the field of diabetes treatment. Based on an example evaluating HbA1c reduction with linagliptin versus sitagliptin, the model used seems a valid approach for indirect drug comparisons.

Prediction of cardiovascular events, diabetic nephropathy, and mortality by albumin concentration in a spot urine sample in patients with type 2 diabetes

AIMS

To analyze in a random urine spot the predictive value of urinary albumin concentration (UAC) for cardiovascular events, diabetic nephropathy (DN), and death in patients with type 2 diabetes.

METHODS

In this cohort, urinary albumin (immunoturbidimetry) was measured as 24-h urinary albumin excretion (UAE) and, in a random spot urine, as UAC and albumin:creatinine ratio (ACR). Primary outcomes were: 1) cardiovascular events, 2) DN defined as a composite outcome [macroalbuminuria and/or decreased glomerular filtration rate (GFR) <60 ml/min/1.73 m²], and 3) death.

RESULTS

A total of 199 type 2 diabetic patients, aged 59.9 ± 9.9 years, were followed for 6.1 ± 2.7 years. UAC ≥14.4 mg/l, as determined by ROC curve, predicted DN and prediction for this and other outcomes were compared with traditional microalbuminuria cutoffs for ACR and UAE. The outcomes frequency was: cardiovascular events = 26.4%, DN = 31.7% (23.5% decreased GFR; 13.6% macroalbuminuria) and death = 8.50%. In Cox analyses, UAC ≥14 mg/l increased the risk (hazard ratio, HR) for cardiovascular events 3.25 times (95% CI 1.43-7.38; P = 0.005), 4.30 for DN composite outcome (95% CI 2.22-8.32; P <0.001), and 5.51 for death (95% CI 1.16-26.22; P = 0.032). Corresponding HRs of ACR ≥30 mg/g were: 2.89 (95% CI 1.29-6.45; P = 0.009) for cardiovascular events, 4.67 (95% CI 2.34-9.34; P <0.001) for DN composite outcome and 5.07 (95% CI 1.01-24.88; P = 0.049) for death. HRs of UAE ≥30 mg/24-h were: 2.20 (95% CI 2.08-2.49; P = 0.030) for cardiovascular events, 6.76 (95% CI 3.32-13.77; P <0.001) for DN composite outcome, and 2.47 (95% CI 0.72-8.42; P = 0.150) for death.

CONCLUSIONS

In conclusion, random UAC ≥14 mg/l predicted cardiovascular events, diabetic nephropathy, and mortality just as well as ACR. UAC may be used to assess cardiovascular and renal risks in patients with type 2 diabetes.

Pré-diabetes: diagnóstico, avaliação de complicações crônicas e tratamento

O diabetes melito do tipo 2 (DM2) é responsável por 90% dos casos de diabetes e está associado a complicações micro e macrovasculares de elevada morbimortalidade. Os indivíduos com maior risco de desenvolvimento de DM incluem aqueles com glicemia de jejum alterada (GJA) e tolerância diminuída à glicose (TDG) e especialmente aqueles com as duas condições combinadas. Esses indivíduos fazem parte de um grupo hoje conhecido como pré-diabetes. Aproximadamente 25% dos indivíduos com pré-diabetes desenvolverão DM2 em três a cinco anos. A hiperglicemia, na ausência de DM, também foi associada ao aumento no risco de doença cardiovascular. Estudos demonstraram que mudanças no estilo de vida e intervenções medicamentosas são efetivas em retardar ou prevenir o DM2 em pacientes com pré-diabetes. GJA e TDG estão associadas ao desenvolvimento de DM2 e, apesar das controvérsias, a maioria dos estudos epidemiológicos reforça a importância dessas duas condições também no desenvolvimento de doença micro e macrovascular. Assim, intervenções em pacientes com pré-diabetes são importantes na prevenção primária do DM2 e de suas complicações crônicas.

Glucose tolerance status is a better predictor of diabetes and cardiovascular outcomes than metabolic syndrome: a prospective cohort study

BACKGROUND

To evaluate the importance of oral glucose tolerance test (OGTT) in predicting diabetes and cardiovascular disease in patients with and without Metabolic Syndrome from a population treated in a primary care unit.

RESEARCH DESIGN AND METHODS

A prospective cohort study was conducted with subjects regularly attending the primary care unit of Hospital de Clínicas de Porto Alegre. Participants underwent a 75 g OGTT. Metabolic syndrome definition was based on the criteria of IDF/AHA/NHLBI-2010.

RESULTS

Participants mean age was 61 ± 12 years (males: 38%; whites: 67%). Of the 148 subjects included, 127 (86%) were followed for 36 ± 14 months, 21 (14%) were lost. Subjects were classified into four groups based on baseline OGTT: 29% normal (n = 43), 28% impaired fasting glucose (IFG; n = 42), 26% impaired glucose tolerance (IGT; n = 38), and 17% diabetes (n = 25). Metabolic syndrome prevalence was lower in normal group (28%), intermediate in IFG (62%) and IGT (65%) groups, and higher among subjects with diabetes (92%; P <0.001). Incidence of diabetes increased along with the stages of glucose metabolism disturbance (normal: 0%, IFG: 16%, IGT: 28%; P = 0.004). No patient with normal OGTT developed diabetes, regardless metabolic syndrome presence. Diabetes at baseline was the major determinant of cardiovascular disease occurrence (normal: 0%, IFG: 4%, IGT: 0%, diabetes: 24%; P = 0.001). In Cox-regression analysis, only the 2 h OGTT results were associated with diabetes (OR = 1.03; 95%CI 1.01-1.06; P <0.001) and cardiovascular disease development (OR = 1.013; 95%CI 1.002-1.025; P = 0.024).

CONCLUSIONS

In this sample of subjects undergoing diabetes screening, the OGTT predicted diabetes and cardiovascular disease more effectively than the metabolic syndrome status.

Humidification of inspired gases during mechanical ventilation

Humidification of inspired gas is mandatory for all mechanically ventilated patients to prevent secretion retention, tracheal tube blockage and adverse changes occurring to the respiratory tract epithelium. However, the debate over "ideal" humidification continues. Several devices are available that include active and passive heat and moisture exchangers and hot water humidifiers Each have their advantages and disadvantages in mechanically ventilated patients. This review explores each device in turn and defines their role in clinical practice.

Clinical features of patients with type 2 diabetes mellitus and hepatitis C infection

The objective of the present cross-sectional study was to assess the prevalence and the clinical and laboratory features of hepatitis C virus (HCV)-positive patients with type 2 diabetes mellitus (DM) attending either an outpatient clinic or hemodialysis units. Serologic-HCV testing was performed in 489 type 2 DM patients (303 outpatients and 186 on dialysis). A structured assessment of clinical, laboratory and DM-related complications was performed and the patients were then compared according to HCV infection status. Mean patient age was 60 years; HCV positivity (HCV+) was observed in 39 of 303 (12.9%) outpatients and in 34 of 186 (18.7%) dialysis patients. Among HCV+ patients, 32 were men (43.8%). HCV+ patients had higher serum levels of aspartate aminotransferase (0.90 ± 0.83 vs 0.35 ± 0.13 μKat/L), alanine aminotransferase (0.88 ± 0.93 vs 0.38 ± 0.19 μKat/L), gamma-glutamyl transferase (1.57 ± 2.52 vs 0.62 ± 0.87 μKat/L; P < 0.001), and serum iron (17.65 ± 6.68 vs 14.96 ± 4.72 μM; P = 0.011), and lower leukocyte and platelet counts (P = 0.010 and P < 0.001, respectively) than HCV-negative (HCV-) patients. HCV+ dialysis patients had higher diastolic blood pressure than HCV- patients (87.5 ± 6.7 vs 81.5 ± 6.0 mmHg; P = 0.005) and a lower prevalence of diabetic retinopathy (75 vs 92.7%; P = 0.007). In conclusion, our study showed that HCV is common among subjects with type 2 DM but is not associated with a higher prevalence of chronic diabetic complications.

Endothelin-1 and endothelin a receptor immunoreactivity is increased in patients with diabetic nephropathy

BACKGROUND

Endothelin-1 (ET-1) is associated with progression of renal disease, acting as a vasoconstrictor and growth factor for mesangial cells. ET-1 and endothelin A receptor (ET-RA) might have a role in the development of diabetic nephropathy (DN). The aims of this study were to determine ET-1 and ET-RA expressions in patients with DN and to correlate these expressions with renal function and proteinuria.

MATERIALS AND METHODS

This is a cross-sectional study comprising 13 patients with type 2 diabetes mellitus and DN, 10 patients with proteinuric IgA nephropathy, and 13 samples of normal kidney from tumor nephrectomies. Demographic and selected data were collected from medical charts. The distribution and intensity of ET-1 and ET-RA immunostaining in renal biopsies were determined by immunohistochemistry and these correlated with the estimated glomerular filtration rate (eGFR) and proteinuria.

RESULTS

Patients with DN and IgA nephropathy on biopsy had markedly increased staining for ET-1 in endothelial cells of glomerular and peritubular capillaries when compared with controls (p < 0.001). ET-RA staining was also more intense and more diffuse in DN and IgA nephropathy than in controls (p = 0.019) and was restricted to tubular epithelial cells. A positive correlation was observed between ET-1 expression and proteinuria (r = 0.634, p = 0.027), but both ET-1 and ET-RA expressions did not correlate with eGFR.

CONCLUSION

In this preliminary report, the higher expressions of ET-1 and ET-RA found in both DN and IgA nephropathy suggest a potential role for the endothelin system in DN as well as in other nondiabetic glomerular diseases.

The role of uncoupling protein 2 (UCP2) on the development of type 2 diabetes mellitus and its chronic complications

It is well established that genetic factors play an important role in the development of type 2 diabetes mellitus (DM2) and its chronic complications, and that genetically susceptible subjects can develop the disease after being exposed to environmental risk factors. Therefore, great efforts have been made to identify genes associated with DM2. Uncoupling protein 2 (UCP2) is expressed in several tissues, and acts in the protection against oxidative stress; in the negative regulation of insulin secretion by beta cells, and in fatty acid metabolism. All these mechanisms are associated with DM2 pathogenesis and its chronic complications. Therefore, UCP2 is a candidate gene for the development of these disorders. Indeed, several studies have reported that three common polymorphisms in UCP2 gene are possibly associated with DM2 and/or obesity. Only a few studies investigated these polymorphisms in relation to chronic complications of diabetes, with inconclusive results.

The rs7204609 polymorphism in the fat mass and obesity-associated gene is positively associated with central obesity and microalbuminuria in patients with type 2 diabetes from Southern Brazil

OBJECTIVE

Single nucleotide polymorphisms (SNPs) in the fat mass and obesity-associated (FTO) gene, especially the common rs9939609 (A/T) SNP, are associated with body mass index (BMI), diabetes, and metabolic syndrome (MetS). MetS is highly prevalent in patients with type 2 diabetes and has been associated with chronic diabetic complications. Therefore, the aim of this study was to evaluate possible associations of the scarcely investigated rs7204609 (C/T) polymorphism, as well as the rs9939609 (A/T) polymorphism, with MetS and chronic diabetic complications in type 2 diabetic patients from Southern Brazil.

DESIGN

This was a cross-sectional study.

PATIENTS AND METHODS

A total of 236 patients with type 2 diabetes (age: 60.0 ± 10.3 years; diabetes duration: 12.7 ± 8.2 years; 53.4% women) were genotyped for the FTO rs7204609 and rs9939609 polymorphisms (ABI PRISM 7000 Real-Time PCR System). Patients underwent clinical, laboratory, and nutritional evaluation. MetS was defined according to the 2009-Joint Interim Statement.

RESULTS

Carriers of C allele of the rs7204609 polymorphism (CT/CC genotypes, n = 35) were at increased risk for the presence of MetS (odds ratio [OR] = 4.56; 95% CI: 1.04 to 19.9), elevated waist circumference (OR = 8.66; 95% CI: 1.12 to 66.7), BMI: ≥ 30 kg/m(2) (OR = 3.71; 95% CI: 1.71 to 8.02), and microalbuminuria (OR = 2.30; 95% CI: 1.08 to 4.88), adjusted for gender and diabetes duration (P < .05 for all models). The rs9939609 polymorphism was not associated with MetS, elevated waist circumference or BMI, or diabetic complications. Daily energy and nutrient intakes did not differ according to the presence of the polymorphisms.

CONCLUSIONS

The C allele of the rs7204609 polymorphism in the FTO gene increased the chance for the presence of MetS, especially central obesity, and microalbuminuria, independently of energy and nutrient intakes in this sample of type 2 diabetic patients from Southern Brazil.

Efficacy and safety of topiramate on weight loss: a meta-analysis of randomized controlled trials

Topiramate was associated with weight loss in clinical trials. We summarize the evidence on the efficacy and safety of topiramate in the treatment of overweight/obesity. The databases Medline, Embase, and Cochrane were searched. Randomized controlled studies with at least 16 weeks of duration that report the effect of topiramate on weight loss and adverse events were eligible for inclusion. Ten studies were included (3320 individuals). Patients treated with topiramate lost an average of 5.34 kg (95% confidence interval [95%CI]-6.12 to -4.56) of additional weight as compared with placebo. According to meta-regression analysis, treatment duration and dosage were associated with the efficacy of topiramate treatment. Evaluating trials using topiramate 96-200 mg day(-1) , the weight loss was higher in trials with >28 weeks of duration (-6.58 kg [95%CI -7.48 to -5.68]) than in trials with ≤28 weeks (-4.11 kg [95%CI -4.92 to -3.30]). Data of 6620 individuals were available for adverse events evaluation and those more frequently observed were paraesthesia, taste impairment and psychomotor disturbances. The odds ratio for adverse events leading to topiramate withdrawal was 1.94 (95%CI 1.64-2.29) compared with the control group. In conclusion, topiramate might be a useful adjunctive therapeutic tool in the treatment of obesity as long as proper warnings about side effects are considered.

Pituitary gland metastasis from renal cell carcinoma presented as a non-functioning macroadenoma

Metastatic tumors involving the pituitary gland are an uncommon finding and occur in up to 1% of all pituitary tumor resections. A 74-year-old man had progressive vision deterioration, over the 30 days prior to consultation. He did not complain of headache or polyuria, but referred to intestinal constipation. Five years ago, he underwent a right radical nephrectomy for renal cell carcinoma, followed by chemotherapy and radiotherapy for lung and parotid metastases. On ophthalmologic examination, there was a left abducens nerve palsy and bitemporal hemianopia. Magnetic resonance imaging demonstrated a sellar mass with suprasellar cistern extension compressing the optic chiasm. Endocrinological evaluation revealed central adrenal and gonadal insufficiencies. The patient underwent a transsphenoidal tumor resection that revealed renal cell carcinoma. This case illustrates that metastatic pituitary lesions can mimic typical symptoms and signs of pituitary macroadenoma. Furthermore, clinical diabetes insipidus, a common finding of pituitary metastases, can be absent.

Hypertension is the metabolic syndrome component most strongly associated with microvascular complications and coronary artery calcification in Type 1 diabetes

AIM

To evaluate the association of metabolic syndrome (MetS) and its individual components with microvascular complications and coronary artery calcification (CAC) in patients with Type 1 diabetes.

MATERIAL/SUBJECTS AND METHODS

Cross-sectional study included 261 patients with Type 1 diabetes. Patients were assessed regarding the presence of MetS according to National Cholesterol Education Program (NCEP) criteria. CAC score was measured in a subset of 100 patients without known cardiovascular disease.

RESULTS

The prevalence of MetS was 13.4% according to the NCEP criteria. Microvascular complications and CAC were more frequent in patients with MetS. In a multiple logistic regression analysis, MetS remained associated with nephropathy [OR: 6.33 (95% CI 2.54-15.77), p<0.001], but not with retinopathy and CAC. Among the MetS components, hypertension was associated with presence of retinopathy [OR: 4.04 (95% CI 1.65- 9.90), p=0.002], nephropathy [OR: 5.92 (95% CI 2.42-14.4), p<0.001] and CAC [OR: 2.97 (95% CI 1.06-8.30), p=0.03].

CONCLUSIONS

Hypertension was the only MetS component associated with retinopathy, nephropathy and the presence of CAC. Hypertension was better associated with CAC than MetS itself.

HbA(1c) measurement for the diagnosis of diabetes: is it enough?

AIM

To analyse the performance of HbA(1c) in diagnosing Type 2 diabetes based on fasting plasma glucose and/or 2-h plasma glucose measurements after a 75-g oral glucose tolerance test.

METHODS

This is a study of diagnostic test accuracy in individuals referred to the Clinical Pathology Department for oral glucose tolerance testing. After fasting overnight, HbA(1c), fasting plasma glucose and 2-h plasma glucose were measured. The receiver operating characteristic curve was used to evaluate the diagnostic performance of HbA(1c).

RESULTS

Four hundred and ninety-eight subjects (195 male, mean age 56 years) were enrolled and 115 (23.1%) were diagnosed with diabetes according to glucose-based methods and only 56 (11.2%) individuals were identified by HbA(1c) ≥ 6.5% (48 mmol/mol) (sensitivity 20.9%, specificity 95.3%). There is poor agreement between the newly recommended criterion and the current glucose-based diagnostic criteria (κ = 0.217; P < 0.001), probably because the diagnostic methods identify different populations of patients. Adding a glucose-based method into an algorithm, as proposed by the UK Department of Health, improved HbA(1c) performance.

CONCLUSIONS

HbA(1c) ≥ 6.5% (48 mmol/mol) showed limited sensitivity to diabetes diagnosis, although with high specificity. The results suggest that this cut-off point would not be enough to diagnose diabetes. Its use as the sole diabetes diagnostic test should be interpreted with caution to assure the correct classification of diabetic individuals.

[Macrovascular diabetic complications: clinical characteristics, diagnosis and management]

Diabetes mellitus (DM) is an independent risk factor for coronary heart disease, stroke, peripheral arterial disease and heart failure, which are the main causes of death in these patients. Moreover, patients with DM and cardiovascular disease have a worse prognosis than nondiabetics, present lower short-term survival, higher risk of recurrence of the disease and a worse response to the treatments proposed. In the last decades, diagnostic and therapeutic progress had already shown benefits concerning cardiovascular risk reduction in these patients, but their absolute mortality risk is still twice that of non-diabetic patients. Because of this, the adoption of intensive treatment, with strict cardiovascular risk factor control, is a priority. The present study presents the main clinical characteristics and also the practical approach for screening, diagnosis and treatment of patients with diabetic macrovascular disease.

Alogliptin added to insulin therapy in patients with type 2 diabetes reduces HbA(1C) without causing weight gain or increased hypoglycaemia

AIMS

To assess the efficacy and safety of alogliptin added to insulin in patients with type 2 diabetes inadequately controlled with insulin alone or combined with metformin.

METHODS

In this 26-week, double-blind, placebo-controlled study, 390 patients were randomized to receive alogliptin 12.5 mg (n = 131), alogliptin 25 mg (n = 129) or placebo (n = 130) once daily, as add-on to stable insulin therapy with or without metformin. The primary endpoint was change in haemoglobin A(1C) (HbA(1C)) at week 26.

RESULTS

At week 26, mean HbA(1C) changes from the mean baseline value of 9.3% were significantly greater for alogliptin 12.5 mg (-0.63 +/- 0.08%) and alogliptin 25 mg (-0.71 +/- 0.08%) than placebo (-0.13 +/- 0.08%; p < 0.001). Significantly greater proportions of patients receiving alogliptin 12.5 or 25 mg than placebo had HbA(1C) decreases of > or =0.5, > or =1.0 and > or =1.5%. Insulin doses remained unchanged, and there were no differences in the proportions of patients experiencing hypoglycaemia among placebo (24%), alogliptin 12.5 mg (27%) and alogliptin 25 mg (27%). Mean weight increases from baseline at week 26 were similar for placebo (0.6 +/- 0.2 kg), alogliptin 12.5 mg (0.7 +/- 0.2 kg) and alogliptin 25 mg (0.6 +/- 0.2 kg). Incidences of overall adverse events, and of gastrointestinal, dermatological and infection-related events, were similar among groups.

CONCLUSIONS

Adding alogliptin to previous insulin therapy (with or without metformin) significantly improved glycaemic control in patients with type 2 diabetes inadequately controlled on insulin, without causing weight gain or increasing the incidence of hypoglycaemia. Further studies are warranted to explore the role of alogliptin added to optimized basal insulin regimens.

Diabetic retinopathy is associated with early autonomic dysfunction assessed by exercise-related heart rate changes

Diabetic retinopathy has been associated with cardiac autonomic dysfunction in both type 1 and type 2 diabetes mellitus (DM) patients. Heart rate (HR) changes during exercise testing indicate early alterations in autonomous tonus. The aim of the present study was to investigate the association of diabetic retinopathy with exercise-related HR changes. A cross-sectional study was performed on 72 type 2 and 40 type 1 DM patients. Autonomic dysfunction was assessed by exercise-related HR changes (Bruce protocol). The maximum HR increase, defined as the difference between the peak exercise rate and the resting rate at baseline, and HR recovery, defined as the reduction in HR from the peak exercise to the HR at 1, 2, and 4 min after the cessation of the exercise, were determined. In type 2 DM patients, lower maximum HR increase (OR = 1.62, 95%CI = 1.03-2.54; P = 0.036), lower HR recovery at 2 (OR = 2.04, 95%CI = 1.16-3.57; P = 0.012) and 4 min (OR = 2.67, 95%CI = 1.37-5.20; P = 0.004) were associated with diabetic retinopathy, adjusted for confounding factors. In type 1 DM, the absence of an increase in HR at intervals of 10 bpm each during exercise added 100% to the odds for diabetic retinopathy (OR = 2.01, 95%CI = 1.1-3.69; P = 0.02) when adjusted for DM duration, A1c test and diastolic blood pressure. In conclusion, early autonomic dysfunction was associated with diabetic retinopathy. The recognition of HR changes during exercise can be used to identify a high-risk group for diabetic retinopathy.

The efficacy and safety of saxagliptin when added to metformin therapy in patients with inadequately controlled type 2 diabetes with metformin alone

OBJECTIVE

This 24-week trial assessed the efficacy and safety of saxagliptin as add-on therapy in patients with type 2 diabetes with inadequate glycemic control with metformin alone.

RESEARCH DESIGN AND METHODS

This was a randomized, double-blind, placebo-controlled study of saxagliptin (2.5, 5, or 10 mg once daily) or placebo plus a stable dose of metformin (1,500-2,500 mg) in 743 patients (A1C > or =7.0 and < or =10.0%). Efficacy analyses were performed using an ANCOVA model using last observation carried forward methodology on primary (A1C) and secondary (fasting plasma glucose [FPG] and postprandial glucose [PPG] area under the curve [AUC]) end points.

RESULTS

Saxagliptin (2.5, 5, and 10 mg) plus metformin demonstrated statistically significant adjusted mean decreases from baseline to week 24 versus placebo in A1C (-0.59, -0.69, and -0.58 vs. +0.13%; all P < 0.0001), FPG (-14.31, -22.03, and -20.50 vs. +1.24 mg/dl; all P < 0.0001), and PPG AUC (-8,891, -9,586, and -8,137 vs. -3,291 mg . min/dl; all P < 0.0001). More than twice as many patients achieved A1C <7.0% with 2.5, 5, and 10 mg saxagliptin versus placebo (37, 44, and 44 vs. 17%; all P < 0.0001). beta-Cell function and postprandial C-peptide, insulin, and glucagon AUCs improved in all saxagliptin treatment groups at week 24. Incidence of hypoglycemic adverse events and weight reductions were similar to those with placebo.

CONCLUSIONS

Saxagliptin once daily added to metformin therapy was generally well tolerated and led to statistically significant improvements in glycemic indexes versus placebo added to metformin in patients with type 2 diabetes inadequately controlled with metformin alone.