Antiplatelet therapy for every diabetic person?

Factors associated with stroke, myocardial infarction, ischemic heart disease, unstable angina, or mortality in patients from real world clinical practice with newly-diagnosed type 2 diabetes and early glycemic control

OBJECTIVES

The objective of this study was to identify factors associated with stroke, myocardial infarction (MI), all-cause mortality, or a diagnosis of ischemic heart disease (IHD) or unstable angina (UA), among patients newly-diagnosed with type 2 diabetes (T2DM) with no recent history of cardiovascular (CV) events who rapidly achieve and maintain HbA_1c ≤8.0%.

METHODS

Data were obtained from the Clinical Practice Research Datalink (CPRD) from January 1990 to December 2012. A nested case-control design was used with Cox proportional hazards analysis. Cases were identified by the first occurrence of stroke, MI, IHD, UA, or death within 5 years after HbA_1c ≤ 8.0% was first reached (index date) following T2DM diagnosis. Controls were selected using a risk-set sampling approach and were matched 4:1 to cases using index date, exposure time, age, gender, and HbA_1c at index date.

RESULTS

A total of 11,426 T2DM patients met the inclusion criteria for cases. Of these, 5,261 experienced a CV event. Stroke was the most frequent CV event (40%), followed by IHD (29%), MI (22%), and UA (9%). Mean HbA1c ≥7.0% over the length of exposure (vs 6.5 to <7.0%) was associated with an increased risk of stroke, MI, and IHD. The use of anti-platelet medications at baseline was also associated with increased risk of stroke (HR = 1.82 [CI = 1.60-2.06]), MI (HR = 1.67 [CI = 1.38-2.03]), and IHD (HR = 1.85 [CI = 1.57-2.17]). Mean HbA1c < 6.0% was associated with increased risk of stroke (HR = 1.29 [CI = 1.02-1.63]) and IHD (HR = 1.65 [CI = 1.25-2.19]). Use of nitrate medications at baseline was associated with increased risk of MI (HR = 2.83 [CI = 2.24-3.57]), IHD (HR = 4.32 [CI = 3.57-5.22]), and UA (HR = 10.38 [CI = 7.67-14.03]).

CONCLUSIONS

Early and sustained HbA_1c control between 6.5 and <7.0% appears to be an important modifiable factor that helps reduce CV risk in patients with newly-diagnosed T2DM in real-world clinical practice.

Refining Long-Term Prediction of Cardiovascular Risk in Diabetes - The VILDIA Score

Cardiovascular risk assessment in patients with diabetes relies on traditional risk factors. However, numerous novel biomarkers have been found to be independent predictors of cardiovascular disease, which might significantly improve risk prediction in diabetic patients. We aimed to improve prediction of cardiovascular risk in diabetic patients by investigating 135 evolving biomarkers. Based on selected biomarkers a clinically applicable prediction algorithm for long-term cardiovascular mortality was designed. We prospectively enrolled 864 diabetic patients of the LUdwigshafen RIsk and Cardiovascular health (LURIC) study with a median follow-up of 9.6 years. Independent risk factors were selected using bootstrapping based on a Cox regression analysis. The following seven variables were selected for the final multivariate model: NT-proBNP, age, male sex, renin, diabetes duration, Lp-PLA2 and 25-OH vitamin D3. The risk score based on the aforementioned variables demonstrated an excellent discriminatory power for 10-year cardiovascular survival with a C-statistic of 0.76 (P < 0.001), which was significantly better than the established UKPDS risk engine (C-statistic = 0.64, P < 0.001). Net reclassification confirmed a significant improvement of individual risk prediction by 22% (95% confidence interval: 14–30%) compared to the UKPDS risk engine (P < 0.001). The VILDIA score based on traditional cardiovascular risk factors and reinforced with novel biomarkers outperforms previous risk algorithms.

Platelets, diabetes and myocardial ischemia/reperfusion injury

Mechanisms underlying the pathogenesis of ischemia/reperfusion injury are particularly complex, multifactorial and highly interconnected. A complex and entangled interaction is also emerging between platelet function, antiplatelet drugs, coronary diseases and ischemia/reperfusion injury, especially in diabetic conditions. Here we briefly summarize features of antiplatelet therapy in type 2 diabetes (T2DM). We also treat the influence of T2DM on ischemia/reperfusion injury and how anti-platelet therapies affect post-ischemic myocardial damage through pleiotropic properties not related to their anti-aggregating effects. miRNA-based signature associated with T2DM and its cardiovascular disease complications are also briefly considered. Influence of anti-platelet therapies and different effects of healthy and diabetic platelets on ischemia/reperfusion injury need to be further clarified in order to enhance patient benefits from antiplatelet therapy and revascularization. Here we provide insight on the difficulty to reduce the cardiovascular risk in diabetic patients and report novel information on the cardioprotective role of widely used anti-aggregant drugs.

Neutrophil-derived S100 calcium-binding proteins A8/A9 promote reticulated thrombocytosis and atherogenesis in diabetes

Platelets play a critical role in atherogenesis and thrombosis-mediated myocardial ischemia, processes that are accelerated in diabetes. Whether hyperglycemia promotes platelet production and whether enhanced platelet production contributes to enhanced atherothrombosis remains unknown. Here we found that in response to hyperglycemia, neutrophil-derived S100 calcium-binding proteins A8/A9 (S100A8/A9) interact with the receptor for advanced glycation end products (RAGE) on hepatic Kupffer cells, resulting in increased production of IL-6, a pleiotropic cytokine that is implicated in inflammatory thrombocytosis. IL-6 acts on hepatocytes to enhance the production of thrombopoietin, which in turn interacts with its cognate receptor c-MPL on megakaryocytes and bone marrow progenitor cells to promote their expansion and proliferation, resulting in reticulated thrombocytosis. Lowering blood glucose using a sodium-glucose cotransporter 2 inhibitor (dapagliflozin), depleting neutrophils or Kupffer cells, or inhibiting S100A8/A9 binding to RAGE (using paquinimod), all reduced diabetes-induced thrombocytosis. Inhibiting S100A8/A9 also decreased atherogenesis in diabetic mice. Finally, we found that patients with type 2 diabetes have reticulated thrombocytosis that correlates with glycated hemoglobin as well as increased plasma S100A8/A9 levels. These studies provide insights into the mechanisms that regulate platelet production and may aid in the development of strategies to improve on current antiplatelet therapies and to reduce cardiovascular disease risk in diabetes.

Aspirin for primary prevention of cardiovascular and all-cause mortality events in diabetes: updated meta-analysis of randomized controlled trials

AIMS

To evaluate the benefits and harms of aspirin for the primary prevention of cardiovascular disease and all-cause mortality events in people with diabetes by conducting a systematic review and meta-analysis.

METHODS

Randomized controlled trials of aspirin compared with placebo (or no treatment) in people with diabetes with no history of cardiovascular disease were identified from MEDLINE, EMBASE, Web of Science, the Cochrane Library and a manual search of bibliographies to November 2015. Study-specific relative risks with 95% CIs were aggregated using random effects models.

RESULTS

A total of 10 randomized trials were included in the review. There was a significant reduction in risk of major adverse cardiovascular events: relative risk of 0.90 (95% CI 0.81-0.99) in groups taking aspirin compared with placebo or no treatment. Limited subgroup analyses suggested that the effect of aspirin on major adverse cardiovascular events differed by baseline cardiovascular disease risk, medication compliance and sex (P for interaction for all > 0.05).There was no significant reduction in the risk of myocardial infarction, coronary heart disease, stroke, cardiovascular mortality or all-cause mortality. Aspirin significantly reduced the risk of myocardial infarction for a treatment duration of ≤ 5 years. There were differences in the effect of aspirin by dosage and treatment duration on overall stroke outcomes (P for interaction for all < 0.05). There was an increase in risk of major or gastrointestinal bleeding events, but estimates were imprecise and not significant.

CONCLUSIONS

The emerging data do not clearly support guidelines that encourage the use of aspirin for the primary prevention of cardiovascular disease in adults with diabetes who are at increased cardiovascular disease risk.

Disordered haematopoiesis and athero-thrombosis

Atherosclerosis, the major underlying cause of cardiovascular disease, is characterized by a lipid-driven infiltration of inflammatory cells in large and medium arteries. Increased production and activation of monocytes, neutrophils, and platelets, driven by hypercholesterolaemia and defective high-density lipoproteins-mediated cholesterol efflux, tissue necrosis and cytokine production after myocardial infarction, or metabolic abnormalities associated with diabetes, contribute to atherogenesis and athero-thrombosis. This suggests that in addition to traditional approaches of low-density lipoproteins lowering and anti-platelet drugs, therapies directed at abnormal haematopoiesis, including anti-inflammatory agents, drugs that suppress myelopoiesis, and excessive platelet production, rHDL infusions and anti-obesity and anti-diabetic agents, may help to prevent athero-thrombosis.

Diabetes mellitus as risk factor for atrial fibrillation hospitalization: Incidence and outcomes over nine years in a region of Northern Italy

AIMS

Diabetes mellitus (DM) and atrial fibrillation (AF) are worldwide public health challenges and major causes of death and cardiovascular events. The association between DM and AF is controversial in literature and data on outcomes of individuals with both diseases have not been evaluated in population studies. We tested the hypothesis that DM is independently associated to AF hospitalization and assessed the risk of stroke and mortality in people with both conditions.

METHODS

We conducted a population-based cohort-study of DM patients and their corresponding controls identified in a administrative health database of the Lombardy Region. Both cohorts were followed for nine years. A multivariable Cox proportional-hazards-regression model was used to estimate the hazard ratio (HR) for first hospitalization for AF and for clinical outcomes.

RESULTS

Out of 9,061,258 residents, 285,428 (3.14%) DM subjects were identified, mean age 65.8±15 years, 49% were women. The cumulative incidence of AF in DM was 10.4% vs. 7.4% in non-DM. DM was a risk factor for AF (HR 1.32, 95% CI 1.30-1.34; p<0.0001). Oral anticoagulants were prescribed in 34.8% of DM patients with AF. DM associated with AF, presented the highest HR for stroke: 2.63; 95% CI 2.47-2.80 and for total death, HR 2.41; 95% CI 2.36-2.47.

CONCLUSIONS

In this population study, DM was an independent risk factor for AF hospitalization. DM patients with AF had the highest risk of stroke and total mortality. Early identification of AF and a structured plan to optimize the comprehensive management of DM and AF patients is mandatory.

Achievement of cardiometabolic goals among diabetic patients in Spain. A nationwide population-based study

BACKGROUND

No previous study has reported a comprehensive assessment of the attainment of cardiometabolic goals in the diabetic population of a European country. We examined the achievement of cardiometabolic goals among diabetics in Spain.

METHODS AND FINDINGS

A cross-sectional survey was performed in 2008-2010 among 12,077 individuals representative of the Spanish population aged ≥18 years. Information on cardiometabolic characteristics was collected at the participants' homes through structured questionnaires, physical examination, and fasting blood samples. Attainment of cardiometabolic goals was evaluated according to the most well-known guidelines. A total of 834 individuals had diabetes (fasting serum glucose ≥126 mg/dl, or glycosylated hemoglobin ≥6.5%,) or were being treated with oral antidiabetic drugs or insulin). Among diabetic patients, 661 (79.2%) were aware of their condition. Among the aware diabetic patients, only 11.4% had neither general (body mass index <25 kg/m(2)) nor abdominal obesity (waist circumference ≤102 cm in men and ≤88 cm in women), 8.6% consumed <7% of calories daily from saturated fats, and 41.1% achieved the recommendation on weekly physical activity. About 71% had glycosylated hemoglobin <7%, 22% had blood pressure <130/80 mmHg, and 36% reached the LDL-cholesterol goal of <100 mg/dl. Although a large proportion of aware diabetic individuals received lifestyle medical advice, only 38% of overweight individuals and 20% of daily smokers were offered a specific strategy for weight loss or quitting smoking, respectively.

CONCLUSIONS

In a European country with universal healthcare coverage, achievement of many cardiometabolic goals, in particular lifestyle, among aware diabetic individuals is poor. This suggests a need for improvement in both clinical guidelines' implementation and patients' adherence.

Primary and secondary prevention of cardiovascular disease in diabetes with aspirin

Diabetes is associated with an increased cardiovascular risk. The role for aspirin in diabetes is of high clinical interest. Guidelines recommend that primary prevention of cardiovascular disease (CVD) in diabetes with aspirin should be based on the individual risk for CVD. New mechanistic studies suggest that enhanced platelet turnover may partly contribute to the fact the primary prevention studies found unequivocal results in diabetes. There is initial evidence that a potential future modification of dosages in diabetes may counteract the enhancement in platelet turnover in diabetes. The use of aspirin in diabetic patients for secondary prevention of CVD is supported by key evidence. The aim of the review is to present recent studies on aspirin for prevention of CVD in diabetes and to highlight its role also in view of new mechanistic and clinical studies with aspirin. Novel aspects of aspirin, e.g. its potential role for the prevention of cancer, are also presented.

Metformin use among individuals at risk for type 2 diabetes

Excess total and cardiovascular morbidity and mortality remain very high among those with type 2 diabetes versus those without diabetes. Clinical trials to lower blood glucose have been disappointing probably because the participants were too late in the natural history of diabetes and already had extensive vascular disease. Insulin resistance measured simply by elevated fasting blood insulin is an early marker of β-cell stress and peripheral insulin resistance. Metformin will prevent development of diabetes among patients with impaired fasting glucose but only for the short term. Metformin reduces risk of coronary heart disease. The drug is safe, low cost, and may also prevent cancer. The combination of diet and exercise followed by metformin in the early phase of "insulin resistance" may reduce or delay both atherosclerosis and arteriosclerosis complications associated with diabetes. Preventive therapy must begin much earlier than before clinical diagnosis of diabetes and aim to initially lower blood insulin levels or insulin resistance.

Statins but not aspirin reduce thrombotic risk assessed by thrombin generation in diabetic patients without cardiovascular events: the RATIONAL trial

BACKGROUND

The systematic use of aspirin and statins in patients with diabetes and no previous cardiovascular events is controversial. We sought to assess the effects of aspirin and statins on the thrombotic risk assessed by thrombin generation (TG) among patients with type II diabetes mellitus and no previous cardiovascular events.

METHODOLOGY/PRINCIPAL FINDINGS

Prospective, randomized, open, blinded to events evaluation, controlled, 2×2 factorial clinical trial including 30 patients randomly allocated to aspirin 100 mg/d, atorvastatin 40 mg/d, both or none. Outcome measurements included changes in TG levels after treatment (8 to 10 weeks), assessed by a calibrated automated thrombogram. At baseline all groups had similar clinical and biochemical profiles, including TG levels. There was no interaction between aspirin and atorvastatin. Atorvastatin significantly reduced TG measured as peak TG with saline (85.09±55.34 nmol vs 153.26±75.55 nmol for atorvastatin and control groups, respectively; p = 0.018). On the other hand, aspirin had no effect on TG (121.51±81.83 nmol vs 116.85±67.66 nmol, for aspirin and control groups, respectively; p = 0.716). The effects of treatments on measurements of TG using other agonists were consistent.

CONCLUSIONS/SIGNIFICANCE

While waiting for data from ongoing large clinical randomized trials to definitively outline the role of aspirin in primary prevention, our study shows that among diabetic patients without previous vascular events, statins but not aspirin reduce thrombotic risk assessed by TG.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00793754.