Eberhard Standl

Secondary prevention of macrovascular events in patients with type 2 diabetes in the PROactive Study (PROspective pioglitAzone Clinical Trial In macroVascular Events): a randomised controlled trial

BACKGROUND Patients with type 2 diabetes are at high risk of fatal and non-fatal myocardial infarction and stroke. There is indirect evidence that agonists of peroxisome proliferator-activated receptor gamma (PPAR gamma) could reduce macrovascular complications. Our aim, therefore, was to ascertain whether pioglitazone reduces macrovascular morbidity and mortality in high-risk patients with type 2 diabetes. METHODS We did a prospective, randomised controlled trial in 5238 patients with type 2 diabetes who had evidence of macrovascular disease. We recruited patients from primary-care practices and hospitals. We assigned patients to oral pioglitazone titrated from 15 mg to 45 mg (n=2605) or matching placebo (n=2633), to be taken in addition to their glucose-lowering drugs and other medications. Our primary endpoint was the composite of all-cause mortality, non fatal myocardial infarction (including silent myocardial infarction), stroke, acute coronary syndrome, endovascular or surgical intervention in the coronary or leg arteries, and amputation above the ankle. Analysis was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN NCT00174993. FINDINGS Two patients were lost to follow-up, but were included in analyses. The average time of observation was 34.5 months. 514 of 2605 patients in the pioglitazone group and 572 of 2633 patients in the placebo group had at least one event in the primary composite endpoint (HR 0.90, 95% CI 0.80-1.02, p=0.095). The main secondary endpoint was the composite of all-cause mortality, non-fatal myocardial infarction, and stroke. 301 patients in the pioglitazone group and 358 in the placebo group reached this endpoint (0.84, 0.72-0.98, p=0.027). Overall safety and tolerability was good with no change in the safety profile of pioglitazone identified. 6% (149 of 2065) and 4% (108 of 2633) of those in the pioglitazone and placebo groups, respectively, were admitted to hospital with heart failure; mortality rates from heart failure did not differ between groups. INTERPRETATION Pioglitazone reduces the composite of all-cause mortality, non-fatal myocardial infarction, and stroke in patients with type 2 diabetes who have a high risk of macrovascular events.

Effect of Sitagliptin on Cardiovascular Outcomes in Type 2 Diabetes

BACKGROUND Data are lacking on the long-term effect on cardiovascular events of adding sitagliptin, a dipeptidyl peptidase 4 inhibitor, to usual care in patients with type 2 diabetes and cardiovascular disease. METHODS In this randomized, double-blind study, we assigned 14,671 patients to add either sitagliptin or placebo to their existing therapy. Open-label use of antihyperglycemic therapy was encouraged as required, aimed at reaching individually appropriate glycemic targets in all patients. To determine whether sitagliptin was noninferior to placebo, we used a relative risk of 1.3 as the marginal upper boundary. The primary cardiovascular outcome was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina. RESULTS During a median follow-up of 3.0 years, there was a small difference in glycated hemoglobin levels (least-squares mean difference for sitagliptin vs. placebo, -0.29 percentage points; 95% confidence interval [CI], -0.32 to -0.27). Overall, the primary outcome occurred in 839 patients in the sitagliptin group (11.4%; 4.06 per 100 person-years) and 851 patients in the placebo group (11.6%; 4.17 per 100 person-years). Sitagliptin was noninferior to placebo for the primary composite cardiovascular outcome (hazard ratio, 0.98; 95% CI, 0.88 to 1.09; P<0.001). Rates of hospitalization for heart failure did not differ between the two groups (hazard ratio, 1.00; 95% CI, 0.83 to 1.20; P=0.98). There were no significant between-group differences in rates of acute pancreatitis (P=0.07) or pancreatic cancer (P=0.32). CONCLUSIONS Among patients with type 2 diabetes and established cardiovascular disease, adding sitagliptin to usual care did not appear to increase the risk of major adverse cardiovascular events, hospitalization for heart failure, or other adverse events. (Funded by Merck Sharp & Dohme; TECOS ClinicalTrials.gov number, NCT00790205.).

Pioglitazone Use and Heart Failure in Patients With Type 2 Diabetes and Preexisting Cardiovascular Disease Data from the PROactive Study (PROactive 08)

OBJECTIVE— PROspective pioglitAzone Clinical Trial In macroVascular Events (PROactive) enrolled patients with type 2 diabetes and preexisting cardiovascular disease. These patients were at high risk for heart failure, so any therapeutic benefit could potentially be offset by risk of associated heart failure mortality. We analyzed the heart failure cases to assess the effects of treatment on morbidity and mortality after reports of serious heart failure. RESEARCH DESIGN AND METHODS— PROactive was an outcome study in 5,238 patients randomized to pioglitazone or placebo. Patients with New York Heart Association Class II–IV heart failure at screening were excluded. A serious adverse event of heart failure was defined as heart failure that required hospitalization or prolonged a hospitalization stay, was fatal or life threatening, or resulted in persistent significant disability or incapacity. Heart failure risk was evaluated by multivariate regression. RESULTS— More pioglitazone (5.7%) than placebo patients (4.1%) had a serious heart failure event during the study (P = 0.007). However, mortality due to heart failure was similar (25 of 2,605 [0.96%] for pioglitazone vs. 22 of 2,633 [0.84%] for placebo; P = 0.639). Among patients with a serious heart failure event, subsequent all-cause mortality was proportionately lower with pioglitazone (40 of 149 [26.8%] vs. 37 of 108 [34.3%] with placebo; P = 0.1338). Proportionately fewer pioglitazone patients with serious heart failure went on to have an event in the primary (47.7% with pioglitazone vs. 57.4% with placebo; P = 0.0593) or main secondary end point (34.9% with pioglitazone vs. 47.2% with placebo; P = 0.025). CONCLUSIONS— Although the incidence of serious heart failure was increased with pioglitazone versus placebo in the total PROactive population of patients with type 2 diabetes and macrovascular disease, subsequent mortality or morbidity was not increased in patients with serious heart failure.

Postprandial Hyperglycemia and Glycemic Variability: Should we care?

The aim of this article is to evaluate the pros and cons of a specific impact of postprandial hyperglycemia and glycemic variability on the—mainly cardiovascular (CV)—complications of diabetes, above and beyond the average blood glucose (BG) as measured by HbA1c or fasting plasma glucose (FPG). The strongest arguments in favor of this hypothesis come from impressive pathophysiological studies, also in the human situation. Measures of oxidative stress and endothelial dysfunction seem to be especially closely related to glucose peaks and even more so to fluctuating high and low glucose concentrations and can be restored to normal by preventing those glucose peaks or wide glucose excursions. The epidemiological evidence, which is more or less confined to postprandial hyperglycemia and postglucose load glycemia, is also rather compelling in favor of the hypothesis, although certainly not fully conclusive as there are also a number of conflicting results. The strongest cons are seen in the missing evidence as derived from randomized prospective intervention studies targeting postprandial hyperglycemia longer term, i.e., over several years, and seeking to reduce hard CV end points. In fact, several such intervention studies in men have recently failed to produce the intended beneficial outcome results. As this evidence by intervention is, however, key for the ultimate approval of a treatment concept in patients with diabetes, the current net balance of attained evidence is not in favor of the hypothesis here under debate, i.e., that we should care about postprandial hyperglycemia and glycemic variability. The absence of a uniformly accepted standard of how to estimate these parameters adds a further challenge to this whole debate.

Oral glucose tolerance test is needed for appropriate classification of glucose regulation in patients with coronary artery disease: a report from the Euro Heart Survey on Diabetes and the Heart

Background: Patients with coronary artery disease (CAD) and abnormal glucose regulation (AGR) are at high risk for subsequent cardiovascular events, underlining the importance of accurate glucometabolic assessment in clinical practice. Objective: To investigate different methods to identify glucose disturbances among patients with acute and stable coronary heart disease. Methods: Consecutive patients referred to cardiologists were prospectively enrolled at 110 centres in 25 countries (n = 4961). Fasting plasma glucose (FPG) and glycaemia 2 h after a 75-g glucose load were requested in patients without known glucose abnormalities (n = 3362). Glucose metabolism was classified according to the World Health Organization and American Diabetes Association (ADA; 1997, 2004) criteria as normal, impaired fasting glucose (IFG), impaired glucose tolerance (IGT) or diabetes. Results: Data on FPG and 2-h post-load glycaemia were available for 1867 patients, of whom 870 (47%) had normal glucose regulation, 87 (5%) had IFG, 591 (32%) had IGT and 319 (17%) had diabetes. If classification had been based on the ADA criterion from 1997, the proportion of misclassified (underdiagnosed) patients would have been 39%. The ADA 2004 criterion would have overdiagnosed 8% and underdiagnosed 33% of the patients, resulting in a total misclassification rate of 41%. For ethical concerns and practical reasons, oral glucose tolerance test (OGTT) was not conducted in 1495 of eligible patients. These patients were more often women, had higher age and waist circumference, and were therefore more likely to have AGR than those who were included. A model based on easily available clinical and laboratory variables, including FPG, high-density lipoprotein cholesterol, age and the logarithm of glycated haemoglobin A1c, misclassified 44% of the patients, of whom 18% were overdiagnosed and 26% were underdiagnosed. Conclusion: An OGTT is still the most appropriate method for the clinical assessment of glucometabolic status in patients with coronary heart disease.

Prediction of Type 1 Diabetes Postpartum in Patients With Gestational Diabetes Mellitus by Combined Islet Cell Autoantibody Screening: A Prospective Multicenter Study

Women with gestational diabetes mellitus (GDM) have a considerable risk of developing diabetes later in life. To determine the predictive value of autoantibody markers in gestational diabetic pregnancy for the development of type 1 diabetes postpartum, we tested 437 patients with GDM (289 women treated with diet only [GDM-A] and 148 requiring insulin treatment during pregnancy [GDM-B]) for antibodies to islet cells (ICAs), GAD (GADAs), and tyrosine phosphatase ICA512/IA-2 (IA2As). We prospectively followed them with repeated oral glucose tolerance tests and antibody determinations for up to 7 years postpartum (mean, 1.6 years; range, 0–7.2 years). The cumulative risk of diabetes up to 5 years postpartum was 17% (95% CI 12–22%). The risk of type 1 diabetes was 3% (2–5%) by 9 months and 7% (4–9%) 2 years after delivery. At delivery, 8.5% of all patients were ICA+, 9.5% were GADA+, 6.2% were IA2A+, and 18.1% were positive for at least one antibody (12.6% for GDM-A vs. 30.4% for GDM-B, P < 0.0001). During follow-up, GADAs persisted in 75%, ICAs in 35%, and IA2As in 30% of the subjects positive for the respective marker at delivery. By 2 years postpartum, 29% (19–39%) of patients positive for at least one antibody developed type 1 diabetes, compared with 2% (1–4%) of antibody-negative patients (P < 0.0001). Thereby, the risk for type 1 diabetes 2 years postpartum increased with the number of antibodies present at delivery from 17% (6–28%) for one antibody, to 61% (30–91%) for two antibodies, and to 84% (55–100%) for 3 antibodies. Risk of progression to type 1 diabetes postpartum was also associated with the status of parity. Women with one or more pregnancies before the index pregnancy had a higher risk for type 1 diabetes 2 years after delivery (14.7% [4.9.–24.5%]) than women having their first (i.e., index) pregnancy (5% [2.9–7.1%]) (P < 0.006). A comparison of different prediction strategies showed that single antibody screening with GADA yielded the highest sensitivity of 63% (45–75%), compared with ICA (48% [31–65%]) and IA2A (34% [13–47%]). Combined screening with two autoantibodies increased sensitivity to 74% (58–90%) and 75% (60–92%) when using GADA plus ICA or GADA plus IA2A, respectively. Screening with all three markers improved sensitivity further to 82% (67–100%). β-cell autoantibodies determined at delivery in women with GDM are highly predictive for the development of type 1 diabetes postpartum. Autoantibody screening in pregnant women with GDM from populations at high risk for type 1 diabetes should therefore be considered to allow early diagnosis and appropriate therapy.

Association Between Sitagliptin Use and Heart Failure Hospitalization and Related Outcomes in Type 2 Diabetes Mellitus: Secondary Analysis of a Randomized Clinical Trial.

IMPORTANCE Previous trial results have suggested that dipeptidyl peptidase 4 inhibitor (DPP4i) use might increase heart failure (HF) risk in type 2 diabetes mellitus (T2DM). The DPP4i sitagliptin has been shown to be noninferior to placebo with regard to primary and secondary composite atherosclerotic cardiovascular (CV) outcomes in the Trial Evaluating Cardiovascular Outcomes With Sitagliptin (TECOS). OBJECTIVE To assess the association of sitagliptin use with hospitalization for HF (hHF) and related outcomes. DESIGN, SETTING, AND PARTICIPANTS TECOS was a randomized, double-blind, placebo-controlled study evaluating the CV safety of sitagliptin vs placebo, each added to usual antihyperglycemic therapy and CV care among patients with T2DM and prevalent atherosclerotic vascular disease. The median follow-up was 2.9 years. The setting was 673 sites in 38 countries. Participants included 14 671 patients with T2DM and atherosclerotic vascular disease. The study dates were December 2008 through March 2015. INTERVENTIONS Patients were randomized to sitagliptin vs placebo added to standard care. MAIN OUTCOMES AND MEASURES Prespecified secondary analyses compared the effect on hHF, hHF or CV death, and hHF or all-cause death composite outcomes overall and in prespecified subgroups. Supportive analyses included total hHF events (first plus recurrent) and post-hHF death. Meta-analyses evaluated DPP4i effects on hHF and on hHF or CV death. RESULTS Of 14 671 patients, 7332 were randomized to sitagliptin and 7339 to placebo. Hospitalization for HF occurred in 3.1% (n = 228) and 3.1% (n = 229) of the sitagliptin and placebo groups, respectively (unadjusted hazard ratio, 1.00; 95% CI, 0.83-1.19). There was also no difference in total hHF events between the sitagliptin (n = 345) and placebo (n = 347) groups (unadjusted hazard ratio, 1.00; 95% CI, 0.80-1.25). Post-hHF all-cause death was similar in the sitagliptin and placebo groups (29.8% vs 28.8%, respectively), as was CV death (22.4% vs 23.1%, respectively). No heterogeneity for the effect of sitagliptin on hHF was observed in subgroup analyses across 21 factors (P > .10 for all interactions). Meta-analysis of the hHF results from the 3 reported DPP4i CV outcomes trials revealed moderate heterogeneity (I2 = 44.9, P = .16). CONCLUSIONS AND RELEVANCE Sitagliptin use does not affect the risk for hHF in T2DM, both overall and among high-risk patient subgroups. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00790205.

Alpha-glucosidase inhibitors 2012 – cardiovascular considerations and trial evaluation

Alpha-glucosidase inhibitors have been available for clinical use for about 20 years. They have shown reasonably good efficacy comparable to other oral blood glucose lowering drugs and in some parts of the world are the most commonly prescribed oral diabetes medication, especially in Asian countries. Unlike as has been observed with some other blood glucose lowering agents, however, no adverse signals of potential cardiovascular harm have emerged in relation to their use. On the contrary, significant beneficial cardiovascular outcome results have been observed in the post-hoc analyses of randomised placebo-controlled trials with the alpha-glucosidase inhibitor acarbose. Targeting mainly postprandial hyperglycaemia, alpha-glucosidase inhibitors favourably affect several cardiovascular risk factors, such as obesity, hypertension and high glycaemic variability with little to no risk for hypoglycaemia. Furthermore, acarbose favourably affects endothelial dysfunction and carotid intima media thickening in humans and, in animal models, improves cardiac interstitial fibrosis and hypertrophy of cardiomyocytes. The ultimate determination of the cardiovascular effects of alpha-glucosidase inhibitors in terms of clinical outcomes awaits the results of ongoing long-term, randomised, placebo-controlled trials.

Guidelines on diabetes, pre-diabetes and cardiovascular diseases

The Task Force on Diabetes and Cardiovascular diseases of the European Society of Cardiology and of the European Association for the Study of Diabetes. European Heart Journal (2007) 28, 88-136.

Reduced Myocardial 123I-Metaiodobenzylguanidine Uptake in Newly Diagnosed IDDM Patients

123I-labeled metaiodobenzylguanidine (123I-MIBG) scintigraphy is a novel technique for the assessment of cardiac sympathetic dysinnervation. To evaluate defects of the cardiac autonomic nervous system at the onset of IDDM, this technique together with conventional electrocardiogram (ECG)-based cardiac reflex tests and measurement of the QT interval was applied to 22 newly diagnosed metabolically stabilized IDDM patients without myocardial perfusion abnormalities (99mTc-labeled methoxyisobutylisonitrile scintigraphy) and 9 matched control subjects. Seventeen diabetic patients (77%), but none of the control subjects, were observed to have a reduced global myocardial uptake of 123I-MIBG. In contrast, only two diabetic patients (9%) demonstrated an ECG-based cardiac autonomic neuropathy (two or more of five age-related cardiac reflex tests abnormal) (P < 0.001). In newly diagnosed IDDM patients, the uptake of 123I-MIBG was reduced more in the posterior myocardial region compared with the lateral and apical region (P < 0.01, P = 0.03). The septal myocardial region exhibited a smaller uptake than the lateral myocardial region (P = 0.02). The maximum/minimum 30:15 ratio correlated with the global, anterior, lateral, and septal myocardial uptake of 123I-MIBG (P < 0.05, P < 0.05, P < 0.01, P < 0.05). A correlation between global and regional myocardial 123IMIBG uptake and HbAlc or QT interval was not observed. Newly diagnosed metabolically stabilized IDDM patients without myocardial perfusion defects show evidence of cardiac sympathetic dysinnervation, as indicated by a reduction of 123I-MIBG uptake, at a significant higher proportion than ECG-based cardiac autonomic neuropathy. Furthermore, they present with regional differences of myocardial 123I-MIBG uptake.