Prävalenz unentdeckter Glukosestoffwechselstörungen in der invasiven und interventionellen Kardiologie: „Silent diabetes“ im Herzkatheterlabor

Comparison of oral glucose tolerance test and HbA1c in detection of disorders of glucose metabolism in patients with acute stroke

Background

Diabetes is an increasingly important risk factor for ischemic stroke and worsens stroke prognosis. Yet a large proportion of stroke patients who are eventually diabetic are undiagnosed. Therefore, it is important to have sensitive assessment of unrecognized hyperglycaemia in stroke patients.

Design

Secondary outcome analysis of a randomized controlled trial focussing on parameters of glucose metabolism and detection of diabetes and prediabetes in patients with acute ischemic stroke (AIS).

Methods

A total of 130 consecutively admitted patients with AIS without previously known type 2 diabetes mellitus (T2DM) were screened for diabetes or prediabetes as part of secondary outcome analysis of a randomized controlled trial that tested lifestyle intervention to prevent post-stroke cognitive decline. Patients had the oral glucose tolerance test (OGTT) and glycated hemoglobin (HbA1c) measurements in the second week after stroke onset and after 1 year. The detection rates of diabetes and prediabetes based on the OGTT or HbA1c values were compared.

Results

By any of the applied tests at the second week after stroke onset 62 of 130 patients (48%) had prediabetes or T2DM. Seventy-five patients had results from both tests available, the OGTT and HbA1c; according to the OGTT 40 (53.3%) patients had normal glucose metabolism, 33 (44%) had prediabetes, two (2.7%) T2DM. In 50 (66.7%) patients the HbA1c results were normal, 24 (32%) in the prediabetic and one (1.3%) in the diabetic range. The detection rate for disorders of glucose metabolism was 10% higher (absolute difference; relative difference 29%) with the OGTT compared with HbA1c. After 1 year the detection rate for prediabetes or T2DM was 7% higher with the OGTT (26% relative difference).

The study intervention led to a more favourable evolution of glycemic status after 1 year.

Conclusion

The OGTT is a more sensitive screening tool than HbA1c for the detection of previously unrecognized glycemic disorders in patients with acute stroke with an at least a 25% relative difference in detection rate. Therefore, an OGTT should be performed in all patients with stroke with no history of diabetes.

Trial registrationhttp://clinicaltrials.gov. Unique identifier: NCT01109836.

The Pathogenesis of Diabetes Mellitus by Oxidative Stress and Inflammation: Its Inhibition by Berberine

A substantial knowledge on the pathogenesis of diabetes mellitus (DM) by oxidative stress and inflammation is available. Berberine is a biologically active botanical that can combat oxidative stress and inflammation and thus ameliorate DM, especially type 2 DM. This article describes the potential of berberine against oxidative stress and inflammation with special emphasis on its mechanistic aspects. In diabetic animal studies, the modified levels of proinflammatory cytokines and oxidative stress markers were observed after administering berberine. In renal, fat, hepatic, pancreatic and several others tissues, berberine-mediated suppression of oxidative stress and inflammation was noted. Berberine acted against oxidative stress and inflammation through a very complex mechanism consisting of several kinases and signaling pathways involving various factors, including NF-κB (nuclear factor-κB) and AMPK (AMP-activated protein kinases). Moreover, MAPKs (mitogen-activated protein kinases) and Nrf2 (nuclear factor erythroid-2 related factor 2) also have mechanistic involvement in oxidative stress and inflammation. In spite of above advancements, the mechanistic aspects of the inhibitory role of berberine against oxidative stress and inflammation in diabetes mellitus still necessitate additional molecular studies. These studies will be useful to examine the new prospects of natural moieties against DM.

[Percutaneous coronary intervention versus bypass surgery in patients with diabetes and multivessel coronary disease. Coronary revascularization after FREEDOM]

Is coronary revascularization required in a patient with chronic stable coronary artery disease or can optimized medical therapy (OMT) alone be a sufficient alternative? This question has been controversially discussed for non-diabetics as well as for diabetics since the COURAGE and BARI 2D trials. According to our present knowledge, a patient will benefit from coronary revascularization only when either a non-invasive test method, such as single photon emission computed tomography (SPECT) or positron emission tomography (PET) myocardial scintigraphy, stress echocardiography or stress nuclear magnetic resonance imaging, can detect relevant, objective evidence of ischemia >10% of the left ventricular myocardium or when a pathological fractional flow reserve (FFR) <0.80 can be measured in an invasive procedure for an angiographically detectable coronary stenosis. If similar relevant ischemia can be non-invasively or invasively objectified in a patient with chronic stable multivessel coronary artery disease, the often controversially discussed question arises particularly in diabetics whether a percutaneous coronary intervention (PCI) with implantation of drug-eluting stents or coronary artery bypass surgery should be favored. The FREEDOM study (Future Revascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multivessel Disease), published in November 2012, was the first prospective randomized study to examine this issue in diabetic patients with multivessel coronary artery disease. Despite a higher rate of stroke in the surgical cohort, after an average follow-up time of 3.8 years a significant prognostic advantage in favor of bypass surgery was detected for a combined primary endpoint of all-cause mortality, nonfatal myocardial infarction and nonfatal stroke. Thus, in the new ESC guidelines on diabetes, pre-diabetes and cardiovascular diseases developed with the EASD of the European Society of Cardiology and published in 2013, coronary bypass surgery has a class I, level of evidence A recommendation for patients with diabetes mellitus, chronic stable multivessel coronary disease and a synergy between PCI with taxus and cardiac surgery (SYNTAX) score >22. The decision for or against a PCI/stent implantation or coronary bypass surgery in a diabetic patient with chronic stable multivessel coronary artery disease should therefore be made with the patient only after a detailed informed consent discussion and comprehensive explanation of both treatment options. In controversial cases, particularly with an equivocal SYNTAX score around 22, relevant comorbidities or anticipated method-specific complications, a one-stage ad hoc intervention during the diagnostic coronary angiography should be rejected in favor of a two-stage procedure with prior discussion of both treatment options in the heart team comprising noninvasive cardiologists, interventional cardiologists and cardiac surgeons.