Low-dose aspirin and vitamin E in people at cardiovascular risk: a randomised trial in general practice. Collaborative Group of the Primary Prevention Project

Meta-analysis: low-dose intake of vitamin E combined with other vitamins or minerals may decrease all-cause mortality

It has been suggested that vitamin E alone or combined with other vitamins or minerals can prevent oxidative stress and slow oxidative injury-related diseases, such as cardiovascular disease and cancer. A comprehensive search of PubMed/MEDLINE, EMBASE and the Cochrane Library was performed. Relative risk was used as an effect measure to compare the intervention and control groups. A total of 33 trials were included in the meta-analysis. Neither vitamin E intake alone (RR=1.01; 95% CI, 0.97 to 1.04; p=0.77) nor vitamin E intake combined with other agents (RR=0.97; 95% CI, 0.89 to 1.06; p=0.55) was correlated with all-cause mortality. Subgroup analyses revealed that low-dose vitamin E supplementation combined with other agents is associated with a statistically significant reduction in all-cause mortality (RR=0.92; 95% CI, 0.86 to 0.98; p=0.01), and vitamin E intake combined with other agents is associated with a statistically significant reduction in mortality rates among individuals without probable or confirmed diseases (RR=0.92; 95% CI, 0.86 to 0.99; p=0.02). Neither vitamin E intake alone nor combined with other agents is associated with a reduction in all-cause mortality. But a low dose (<400 IU/d) of vitamin E combined with other agents is correlated with a reduction in all-cause mortality, and vitamin E intake combined with other agents is correlated with a reduction in the mortality rate among individuals without probable or confirmed diseases.

Supplementation with vitamin E alone is associated with reduced myocardial infarction: a meta-analysis

BACKGROUND AND AIMS

Previous meta-analyses of interventional trials with vitamin E provided negative results but it remains unclear if this vitamin has some influence on cardiovascular events when supplemented alone. The aim of this study was to compare the effect of vitamin E alone or in combination with other antioxidants on myocardial infarction.

METHODS AND RESULTS

Pubmed, ISI Web of Science, SCOPUS and Cochrane database were searched without language restrictions. We investigated randomized clinical trials studying the effect of vitamin E supplementation on myocardial infarction. Sixteen randomized controlled trials of vitamin E treatment were analyzed in this meta-analysis. The dose range for vitamin E was 33-800IU. Follow-up ranged from 0.5 to 9.4 years. Compared to controls, vitamin E given alone significantly decreased myocardial infarction (3.0% vs 3.4%) (random effects R.R.: 0.82; 95% C.I., 0.70-0.96; p = 0.01). This effect was driven by reduction of fatal myocardial infarction (random effects R.R.: 0.84; 95% C.I., 0.73-0.96; p = 0.01).

CONCLUSIONS

When supplemented alone, vitamin E reduces myocardial infarction in interventional trials while it appears ineffective when associated with other antioxidants.

Lack of effect of aspirin in primary CV prevention in type 2 diabetic patients with nephropathy: results from 8 years follow-up of NID-2 study

The risk-to-benefit ratio for the use of low dose of aspirin in primary cardiovascular (CV) prevention in patients with diabetes mellitus remains to be clarified. We assessed the effect of aspirin on risk of CV events in type 2 diabetic patients with nephropathy, in order to verify the usefulness of Guidelines in clinical practice. We carried out a prospective multicentric study in 564 patients with type 2 diabetic nephropathy free of CV disease attending outpatient diabetes clinics . A total of 242 patients received antiplatelet treatment with aspirin 100 mg/day (group A), and 322 were not treated with antiplatelet drugs (group B). Primary end point was the occurrence of total major adverse cardio-vascular events (MACE). Secondary end points were the relative occurrence of fatal MACE. The average follow-up was 8 years. Total MACE occurred in 49 patients from group A and in 52 patients from group B. Fatal MACE occurred in 22 patients from group A and in 20 from group B; nonfatal MACE occurred in 27 patients from group A and in 32 patients from group B. Kaplan-Meier analysis did not show a statistically significant difference of cumulative MACE between the two groups. A not statistically significant difference in the incidence of both fatal (p = 0.225) and nonfatal CV events (p = 0.573) between the two groups was observed. These results were confirmed after adjustment for confounders (HR for MACE 1.11, 95 % CI 0.91-1.35). These findings suggest that low dose of aspirin is ineffective in primary prevention for patients with nephropathy.

A systematic review of aspirin in primary prevention: is it time for a new approach?

Background and Objectives

While evidence in support of aspirin use in secondary prevention is well documented, the role of aspirin in primary prevention remains unclear. We conducted a systematic literature review to evaluate aspirin use in cardiovascular disease (CVD) and cancer primary prevention, and consider whether aspirin’s role is set to become more clearly defined based on past and prospective studies.

Data Sources

Utilizing PubMed, the reviewers identified appropriate Medical Subject Headings (MeSH) terms to establish CVD-based studies, cancer-based studies, and studies on adherence.

Study Eligibility Criteria

Date restrictions of May 31, 2008 to May 31, 2013 were applied to capture the most robust meta-analyses and randomized controlled trials. Websites of relevant EU and US scientific societies were used to identify the key guidelines for aspirin use in primary prevention of CVD, and ClinicalTrials.gov was used to establish future or ongoing trials.

Results

Evidence in support of aspirin prophylaxis is conflicting, though some meta-analyses have underlined potential benefit in reducing cardiovascular events. Despite this apparent benefit, bleeding risk with aspirin is consistently higher versus control, and remains a concern. A reduction of cancer incidence and mortality after a least 3 and 5 years treatment, respectively, is also apparent with aspirin.

Conclusion

Available data on aspirin in primary prevention suggest a modest benefit for patients at high risk of CVD, and a promising benefit for those at risk of cancer. Future studies should help to elucidate whether the benefit of aspirin outweighs risk in appropriate patient groups.

Prophylactic use of aspirin: systematic review of harms and approaches to mitigation in the general population

A careful assessment of benefits and harms is required to assess suitability of aspirin as a prophylactic public health measure. However, comprehensive population-level data on harms are lacking. We collected and synthesized age and sex-specific data on harms relevant to aspirin use in average-risk individuals aged 50 years or older. We conducted systematic literature searches to identify baseline rates of gastrointestinal (GI) bleeding, peptic ulcer, major extra-cranial bleeding, and case-fatality rates due to GI bleeding or peptic ulcer in general population. The magnitude of aspirin-associated increase, the prevalence and attributable risk of Helicobacter pylori infection on these events in aspirin users was also assessed. Baseline rates of major extracranial bleeding events and GI complications increase with age; an almost threefold to fourfold increase is observed from age 50-54 to 70-74 years. Low or standard-dose aspirin use increases GI bleeding events by 60% leading to an annual excess of 0.45 and 0.79 GI bleeding events per 1,000 women and men aged 50-54 years respectively. 5-10% of major GI complications are fatal; a clear age dependence--higher fatality in older individuals, is seen. Eradication of H. pylori infection before aspirin use could reduce the incidence of upper GI complications by 25-30%. GI complications are increased by about 60% due to aspirin use but are fatal only in a very small proportion of individuals younger than 70 years of age. Major bleeding events that are comparable in severity to cancer or CVD, are infrequent. Screening and eradication of H. pylori infection could substantially lower aspirin-related GI harms.

Dietary compliance, dietary supplementation and traditional remedy usage of type 2 diabetic patients with and without cardiovascular disease

This analytical cross-sectional study examined the nutrient intakes, dietary compliance, dietary supplementation and traditional remedy usage in type 2 diabetes mellitus (T2DM) patients from selected tertiary hospitals in multi-racial Malaysia. We compared the different characteristics of T2DM patients with and without cardiovascular disease (CVD). Socio-demographic status, dietary intakes, dietary supplementation, traditional remedy use, medical history, anthropometric measurements and clinical characteristics were obtained from face-to-face interviews. A total of 313 patients who were treated for T2DM participated in this study, in which 36.1% of them had CVD. The mean age of study subjects was 55.7 ± 9.2 years; mean diabetes duration was 10.1 ± 8.1 years; 52.1% were females; and 47.0% were Malays. The mean total energy intake of the subjects was 1674 ± 694 kcal/day, and patients with CVD consumed higher total calories (p = 0.001). Likewise, the mean carbohydrate, protein and total fat intake of CVD patients were significantly higher than non-CVD patients (p < 0.05), while mean intakes of cholesterol, fibre, minerals and all vitamins were comparable between CVD and non-CVD patients. Regardless of CVD status, a notably high proportion of the subjects did not meet the recommendations of the Medical Nutrition Therapy Guidelines for Type 2 Diabetes for total energy, carbohydrate, protein, total fat, and fibre intakes. Meanwhile, 52.4% used at least one dietary supplement and 12.1% took single traditional remedy or in various combinations. Traditional remedies and supplement intake did not differ between CVD and non-CVD subjects. It is suggested that T2DM patients should be educated based on their personalized dietary intake, dietary supplementation and traditional remedy usage. The recommendations for T2DM patients shall be met to achieve the optimal metabolic goals and minimize the potential diabetic complications.

The role of aspirin in the prevention of cardiovascular disease

Aspirin therapy is well-accepted as an agent for the secondary prevention of cardiovascular events and current guidelines also define a role for aspirin in primary prevention. In this review, we describe the seminal trials of aspirin use in the context of current guidelines, discuss factors that may influence the effectiveness of aspirin therapy for cardiovascular disease prevention, and briefly examine patterns of use. The body of evidence supports a role for aspirin in both secondary and primary prevention of cardiovascular events in selected population groups, but practice patterns may be suboptimal. As a simple and inexpensive prophylactic measure for cardiovascular disease, aspirin use should be carefully considered in all at-risk adult patients, and further measures, including patient education, are necessary to ensure its proper use.

Aspirin for primary prevention of cardiovascular events: meta-analysis of randomized controlled trials and subgroup analysis by sex and diabetes status

OBJECTIVE

To evaluate the benefits and harms of aspirin for the primary prevention of CVD and determine whether the effects vary by sex and diabetes status.

METHODS

We searched Medline, Embase, and Cochrane databases for randomized controlled trials comparing the effects of aspirin with placebo or control in people with no pre-existing CVD. Two investigators independently extracted data and assessed the study quality. Analyses were performed using Stata version 12.

RESULTS

Fourteen trials (107,686 participants) were eligible. Aspirin was associated with reductions in major cardiovascular events (risk ratio, 0.90; 95% confidence interval, 0.85-0.95), myocardial infarction (0.86; 0.75-0.93), ischemic stroke (0.86; 0.75-0.98) and all-cause mortality (0.94; 0.89-0.99). There were also increases in hemorrhagic stroke (1.34; 1.01-1.79) and major bleeding (1.55; 1.35-1.78) with aspirin. The number needed to treat to prevent 1 major cardiovascular event over a mean follow-up of 6.8 years was 284. By comparison, the numbers needed to harm to cause 1 major bleeding is 299. In subgroup analyses, pooled results demonstrated a reduction in myocardial infarction among men (0.71; 0.59-0.85) and ischemic stroke among women (0.77; 0.63-0.93). Aspirin use was associated with a reduction (0.65; 0.51-0.82) in myocardial infarction among diabetic men. In meta-regression analyses, the results suggested that aspirin therapy might be associated with a decrease in stroke among diabetic women and a decrease in MI among diabetic men and risk reductions achieved with low doses (75 mg/day) were as large as those obtained with higher doses (650 mg/day).

CONCLUSIONS

The use of low-dose aspirin was beneficial for primary prevention of CVD and the decision regarding an aspirin regimen should be made on an individual patient basis. The effects of aspirin therapy varied by sex and diabetes status. A clear benefit of aspirin in the primary prevention of CVD in people with diabetes needs more trials.

Aspirin therapy in primary cardiovascular disease prevention: a position paper of the European Society of Cardiology working group on thrombosis

Although the use of oral anticoagulants (vitamin K antagonists) has been abandoned in primary cardiovascular prevention due to lack of a favorable benefit-to-risk ratio, the indications for aspirin use in this setting continue to be a source of major debate, with major international guidelines providing conflicting recommendations. Here, we review the evidence in favor and against aspirin therapy in primary prevention based on the evidence accumulated so far, including recent data linking aspirin with cancer protection. While awaiting the results of several ongoing studies, we argue for a pragmatic approach to using low-dose aspirin in primary cardiovascular prevention and suggest its use in patients at high cardiovascular risk, defined as ≥2 major cardiovascular events (death, myocardial infarction, or stroke) projected per 100 person-years, who are not at increased risk of bleeding.

A short-term effect of low-dose aspirin on major hemorrhagic risks in primary prevention: a case-crossover design

BACKGROUND

Very few studies have examined the risk of short-term adverse hemorrhage of low-dose aspirin use in primary prevention. This case-crossover study examined the transient effect of low-dose aspirin use on major hemorrhagic risks.

METHODS

A representative database of 1,000,000 patients randomly sampled from the Taiwan's National Health Insurance Research Database in 2000 was analyzed. The study cohort consisted of a total of 501,946 individuals, aged 30-95 years old, at risk of a major bleeding event in 2000. A case-crossover study was used to retrieve data on 10,905 incident patients with major hemorrhagic complications (3,781 cerebral and 7,124 gastrointestinal) and prescribed low-dose aspirin (≤300 mg/day) from 2000-2008. A 56-day time window (∼2 months) was used as the case period for which the odds ratio (OR) was estimated using the ratio of patients exposed during the 56-day case period only (1-56 days before the index date) compared to its corresponding 56-day control period only (57-112 days before the index date).

RESULTS

Four hundred eighty-nine (4.5%) of the 10,905 hemorrhagic patients had used low-dose aspirin during the 56-day case only period; 294 (2.7%) of the same patients had used low-dose aspirin during control only period. Low-dose aspirin use increase the risk of developing a major hemorrhage 1.33-fold (95% CI = 1.13-1.55, P<0.0001). Significance was found prominent in 4,453 non-hypertensive and non-diabetic subjects (Adjusted odds ratio = 1.88, 95% CI = 1.21-2.91).

CONCLUSION

Transient low-dose aspirin use increases risk for major hemorrhagic events in Han Chinese.

Use of coronary artery calcium testing to guide aspirin utilization for primary prevention: estimates from the multi-ethnic study of atherosclerosis

BACKGROUND

Aspirin for the primary prevention of coronary heart disease (CHD) is only recommended for individuals at high risk for CHD although the majority of CHD events occur in individuals who are at low to intermediate risk.

METHODS AND RESULTS

To estimate the potential of coronary artery calcium (CAC) scoring to guide aspirin use for primary prevention of CHD, we studied 4229 participants from the Multi-Ethnic Study of Atherosclerosis who were not on aspirin at baseline and were free of diabetes mellitus. Using data from median 7.6-year follow-up, 5-year number-needed-to-treat estimations were calculated by applying an 18% relative CHD reduction to the observed event rates. This was contrasted to 5-year number-needed-to-harm estimations based on the risk of major bleeding reported in an aspirin meta-analysis. Results were stratified by a 10% 10-year CHD Framingham Risk Score (FRS). Individuals with CAC≥100 had an estimated net benefit with aspirin regardless of their traditional risk status (estimated 5-year number needed to treat of 173 for individuals <10% FRS and 92 for individuals ≥10% FRS, estimated 5-year number needed to harm of 442 for a major bleed). Conversely, individuals with zero CAC had unfavorable estimations (estimated 5-year number needed to treat of 2036 for individuals <10% FRS and 808 for individuals ≥10% FRS, estimated 5-year number needed to harm of 442 for a major bleed). Sex-specific and age-stratified analyses showed similar results.

CONCLUSIONS

For the primary prevention of CHD, Multi-Ethnic Study of Atherosclerosis participants with CAC≥100 had favorable risk/benefit estimations for aspirin use while participants with zero CAC were estimated to receive net harm from aspirin.

Impact of inflammation on anti-oxidative effects of vitamin E-coated membrane dialyzer in patients on chronic hemodialysis

Hemodialysis (HD) with the use of vitamin E-coated membrane (VEM) dialyzers is shown to exert anti-inflammatory and antioxidative effects in patients with end-stage renal disease on HD. However, the association of baseline inflammatory status with the antioxidative effects of VEM has not been investigated thus far. Thirty-five stable end-stage renal disease patients treated with VEM for 6 months were enrolled in the present prospective, observational cohort study. For the previous 3 months minimum, 17 (48%) patients were dialyzed with a cellulose, eight (23%) patients with a hemophane, and 10 (29%) patients with a polysulfone 1.2 to 1.5 m(2) hollow fiber dialyzer. The effects of treatment on oxidized low-density lipoprotein (oxLDL) were stratified according to half percentiles of baseline serum logC-reactive protein and interleukin-6, and the association between treatment goal, arbitrarily defined as a minimum 30% decrease in baseline oxLDL, was assessed with the use of logistic regression analysis. The higher C-reactive protein and interleukin-6 half percentiles were independently and additively associated with a higher odds ratio for achieving treatment goal. Adjustment for baseline oxLDL, age, sex, HD duration, smoking, and body mass index did not attenuate the odds ratios, whereas the history of diabetes, as primary renal disease, significantly decreased the odds ratio for achieving treatment goal. Increased baseline C-reactive protein and interleukin-6 are independent, additive factors associated with the effect of VEM on oxLDL in HD patients.

Vitamin E-gene interactions in aging and inflammatory age-related diseases: implications for treatment. A systematic review

Aging is a complex biological phenomenon in which the deficiency of the nutritional state combined with the presence of chronic inflammation and oxidative stress contribute to the development of many age-related diseases. Under this profile, the free radicals produced by the oxidative stress lead to a damage of DNA, lipids and proteins with subsequent altered cellular homeostasis and integrity. In young-adult age, the cell has a complex efficient system to maintain a proper balance between the levels of free radicals and antioxidants ensuring the integrity of cellular components. In contrast, in old age this balance is poorly efficient compromising cellular homeostasis. Supplementation with Vitamin E can restore the balance and protect against the deteriorating effects of oxidative stress, progression of degenerative diseases, and aging. Experiments in cell cultures and in animals have clearly shown that Vitamin E has a pivotal role as antioxidant agent against the lipid peroxidation on cell membranes preserving the tissue cells from the oxidative damage. Such a role has been well documented in immune, endothelial, and brain cells from old animals describing how the Vitamin E works both at cytoplasmatic and nuclear levels with an influence on many genes related to the inflammatory/immune response. All these findings have supported a lot of clinical trials in old humans and in inflammatory age-related diseases with however contradictory and inconsistent results and even indicating a dangerous role of Vitamin E able to affect mortality. Various factors can contribute to all the discrepancies. Among them, the doses and the various isoforms of Vitamin E family (α,β,γ,δ tocopherols and the corresponding tocotrienols) used in different trials. However, the more plausible gap is the poor consideration of the Vitamin E-gene interactions that may open new roadmaps for a correct and personalized Vitamin E supplementation in aging and age-related diseases with satisfactory results in order to reach healthy aging and longevity. In this review, this peculiar nutrigenomic and/or nutrigenetic aspect is reported and discussed at the light of specific polymorphisms affecting the Vitamin E bioactivity.

Regulatory metabolites of vitamin E and their putative relevance for atherogenesis

Vitamin E is likely the most important antioxidant in the human diet and α-tocopherol is the most active isomer. α-Tocopherol exhibits anti-oxidative capacity in vitro, and inhibits oxidation of LDL. Beside this, α-tocopherol shows anti-inflammatory activity and modulates expression of proteins involved in uptake, transport and degradation of tocopherols, as well as the uptake, storage and export of lipids such as cholesterol. Despite promising anti-atherogenic features in vitro, vitamin E failed to be atheroprotective in clinical trials in humans. Recent studies highlight the importance of long-chain metabolites of α-tocopherol, which are formed as catabolic intermediate products in the liver and occur in human plasma. These metabolites modulate inflammatory processes and macrophage foam cell formation via mechanisms different than that of their metabolic precursor α-tocopherol and at lower concentrations. Here we summarize the controversial role of vitamin E as a preventive agent against atherosclerosis and point the attention to recent findings that highlight a role of these long-chain metabolites of vitamin E as a proposed new class of regulatory metabolites. We speculate that the metabolites contribute to physiological as well as pathophysiological processes.

Reactive oxygen species in vascular biology: role in arterial hypertension

The cellular metabolism of oxygen generates potentially deleterious reactive oxygen species, including superoxide anion, hydrogen peroxide and hydroxyl radical. Under normal physiologic conditions, the rate and magnitude of oxidant formation is balanced by the rate of oxidant elimination. However, an imbalance between pro-oxidants and antioxidants results in oxidative stress, which is the pathogenic outcome of the overproduction of oxidants that overwhelms the cellular antioxidant capacity. There is growing evidence that increased oxidative stress and associated oxidative damage are mediators of vascular injury in cardiovascular pathologies, including hypertension, atherosclerosis and ischemia-reperfusion. This development has evoked considerable interest because of the possibilities that therapies targeted against reactive oxygen intermediates by decreasing the generation of reactive oxygen species and/or by increasing availability of antioxidants may be useful in minimizing vascular injury. This review focuses on the vascular actions of reactive oxygen species, the role of oxidative stress in vascular damage in hypertension and the therapeutic potential of modulating oxygen radical bioavailability in hypertension. In particular, the following topics will be highlighted: chemistry and sources of reactive oxygen species, antioxidant defense mechanisms, signaling events mediated by reactive oxygen species, role of reactive oxygen species in hypertension and the putative therapeutic role of antioxidants in cardiovascular disease.

Optimizing the use of aspirin for cardiovascular prevention

This article describes the mechanism of action, pharmacokinetics, and pharmacodynamics of aspirin at doses used for cardiovascular prevention and provides specific management recommendations for optimal use in clinical practice. The paper highlights practical aspects related to antiplatelet therapy, including the optimal dose of aspirin, concomitant treatment with other NSAIDs, and strategies for the prevention of gastrointestinal toxicity. Specifically, we revise the benefits and hazards in different clinical settings to help the clinician in the decision-making process for individuals who have different risks for cardiovascular and gastrointestinal bleeding events.

Circulating levels of linoleic acid and HDL-cholesterol are major determinants of 4-hydroxynonenal protein adducts in patients with heart failure

OBJECTIVE

Measurements of oxidative stress biomarkers in patients with heart failure (HF) have yielded controversial results. This study aimed at testing the hypothesis that circulating levels of the lipid peroxidation product 4-hydroxynonenal bound to thiol proteins (4HNE-P) are strongly associated with those of its potential precursors, namely n-6 polyunsaturated fatty acids (PUFA).

METHODS AND RESULTS

Circulating levels of 4HNE-P were evaluated by gas chromatography-mass spectrometry in 71 control subjects and 61 ambulatory symptomatic HF patients along with various other clinically- and biochemically-relevant parameters, including other oxidative stress markers, and total levels of fatty acids from all classes, which reflect both free and bound to cholesterol, phospholipids and triglycerides. All HF patients had severe systolic functional impairment despite receiving optimal evidence-based therapies. Compared to controls, HF patients displayed markedly lower circulating levels of HDL- and LDL-cholesterol, which are major PUFA carriers, as well as of PUFA of the n-6 series, specifically linoleic acid (LA; P=0.001). Circulating 4HNE-P in HF patients was similar to controls, albeit multiple regression analysis revealed that LA was the only factor that was significantly associated with circulating 4HNE-P in the entire population (R (2)=0.086; P=0.02). In HF patients only, 4HNE-P was even more strongly associated with LA (P=0.003) and HDL-cholesterol (p<0.0002). Our results demonstrate that 4HNE-P levels, expressed relative to HDL-cholesterol, increase as HDL-cholesterol plasma levels decrease in the HF group only.

CONCLUSION

Results from this study emphasize the importance of considering changes in lipids and lipoproteins in the interpretation of measurements of lipid peroxidation products. Further studies appear warranted to explore the possibility that HDL-cholesterol particles may be a carrier of 4HNE adducts.

Aspirin in primary prevention of cardiovascular disease and cancer: a systematic review of the balance of evidence from reviews of randomized trials

Background

Aspirin has been recommended for primary prevention of cardiovascular disease (CVD) and cancer, but overall benefits are unclear. We aimed to use novel methods to re-evaluate the balance of benefits and harms of aspirin using evidence from randomised controlled trials, systematic reviews and meta-analyses.

Methods and Findings

Data sources included ten electronic bibliographic databases, contact with experts, and scrutiny of reference lists of included studies. Searches were undertaken in September 2012 and restricted to publications since 2008. Of 2,572 potentially relevant papers 27 met the inclusion criteria. Meta-analysis of control arms to estimate event rates, modelling of all-cause mortality and L'Abbé plots to estimate heterogeneity were undertaken. Absolute benefits and harms were low: 60-84 major CVD events and 34-36 colorectal cancer deaths per 100,000 person-years were averted, whereas 46-49 major bleeds and 68-117 gastrointestinal bleeds were incurred. Reductions in all-cause mortality were minor and uncertain (Hazard Ratio 0.96; 95% CI: 0.90-1.02 at 20 years, Relative Risk [RR] 0.94, 95% CI: 0.88-1.00 at 8 years); there was a non-significant change in total CVD (RR 0.85, 95% CI: 0.69-1.06) and change in total cancer mortality ranged from 0.76 (95% CI: 0.66-0.88) to 0.93 (95% CI: 0.84-1.03) depending on follow-up time and studies included. Risks were increased by 37% for gastrointestinal bleeds (RR 1.37, 95% CI: 1.15-1.62), 54%-66% for major bleeds (Rate Ratio from IPD analysis 1.54, 95% CI: 1.30-1.82, and RR 1.62, 95% CI: 1.31-2.00), and 32%-38% for haemorrhagic stroke (Rate Ratio from IPD analysis 1.32; 95% CI: 1.00-1.74; RR 1.38; 95% CI: 1.01-1.82).

Conclusions

Findings indicate small absolute effects of aspirin relative to the burden of these diseases. When aspirin is used for primary prevention of CVD the absolute harms exceed the benefits. Estimates of cancer benefit rely on selective retrospective re-analysis of RCTs and more information is needed.

Use of antiplatelet agents in patients with atherosclerotic disease

Platelets play a key role in the initiation of hemostatic mechanisms during vascular injury. When contemplating prescription of antiplatelet agents (APAs) for patients as primary prevention for cardiovascular events, the physician should carefully weigh the potential benefits of cardiovascular risk reduction with the likelihood of harm, related mostly to hemorrhagic complications. The role of APAs in secondary prevention of atherosclerosis and coronary artery disease is well established, however, optimal duration of therapy and intensity of patient treatment are not settled and probably need to be individualized per patient. We describe the data emerging from contemporary trials on the efficacy and safety of the use of oral APAs in various patient subpopulations. We also discuss the advantages and potential roles of new APAs during and following acute coronary syndromes, percutaneous coronary interventions, and symptomatic atherosclerosis. We propose certain strategies and directions for future research to enhance the safety and efficacy prevention by optimizing the beneficial effects of APAs along with other contemporary treatment modalities of primary and secondary prevention.

Investigation of the in vivo antioxidative activity of Cynara scolymus (artichoke) leaf extract in the streptozotocin-induced diabetic rat

The in vivo antioxidant activity of a quantified leaf extract of Cynara scolymus (artichoke) was studied. The aqueous artichoke leaf extract (ALE), containing 1.5% caffeoylquinic acid with chlorogenic acid being most abundant (0.30%), and luteolin-7-O-glucoside as major flavonoid (0.15%), was investigated by evaluating the effect on different oxidative stress biomarkers, after 3 wk oral supplementation in the streptozotocin-induced diabetic rat model. Apart from two test groups (0.2 g ALE/kg BW/day and 1 g ALE/kg BW/day, where BW is body weight), a healthy control group, untreated oxidative stress group, and vitamin E treated group (positive control) were included. A 0.2 g/kg BW/day of ALE decreased oxidative stress: malondialdehyde and 8-hydroxydeoxyguanosine levels significantly diminished, whereas erythrocyte glutathione levels significantly increased. A 1.0 g/kg BW/day ALE did not show higher antioxidant activity.

Low-dose aspirin and upper gastrointestinal bleeding in primary versus secondary cardiovascular prevention: a population-based, nested case-control study

BACKGROUND

The benefit-risk profile of low-dose aspirin in primary prevention of cardiovascular disease is unclear. We sought to quantify upper gastrointestinal bleeding (UGIB) risk associated with low-dose aspirin in secondary versus primary prevention patients.

METHODS AND RESULTS

We performed a population-based nested case-control study using The Health Improvement Network (THIN) Database between 2000 and 2007. We identified 2049 cases of UGIB and 20,000 controls, frequency-matched to the cases on age, sex, and calendar year, who were subdivided into primary (without previous cardiovascular disease) and secondary (with previous cardiovascular disease) prevention populations. We estimated the relative risk of UGIB associated with the use of low-dose aspirin by multivariate logistic regression. The UGIB risk in patients taking low-dose aspirin relative to nonusers was significantly higher in the primary (adjusted relative risk, 1.90; 95% confidence interval, 1.59-2.26) than in the secondary (relative risk, 1.40; 95% confidence interval, 1.14-1.72; P value for the difference=0.0014) prevention cohort. However, as the baseline risk of UGIB was lower in the primary than in the secondary prevention cohort, numbers needed to harm per 1 year of low-dose aspirin use were 601 and 391 for primary and secondary prevention, respectively.

CONCLUSIONS

The relative risk of UGIB in patients taking low-dose aspirin is higher when used for primary than for secondary cardiovascular disease prevention, but this difference is more than compensated by the lower baseline risk in the primary prevention population. Such estimates are important for an assessment of the net clinical benefit in primary prevention.

What is an appropriate blood pressure goal for the elderly: review of recent studies and practical recommendations

Hypertension is common in the elderly, and isolated systolic hypertension is responsible for the majority of hypertension in this population. Hypertension in the elderly can be attributed to numerous structural and functional changes to the vasculature that develop with advancing age. Increased systolic blood pressure is associated with adverse outcomes, including stroke, cardiovascular disease, and death. Some studies demonstrate an inverse relationship between cardiovascular outcomes and diastolic blood pressure whereas other studies show a J-shaped or U-shaped association between blood pressure and outcomes. The complex J-shaped association coupled with the unique characteristics of elderly patients have led to much debate and confusion regarding the treatment of hypertension in this population. Clinical trials indicate a benefit to therapy in older adults, and there appears to be no age threshold above which antihypertensive therapy should be withheld. Treatment of hypertension in elderly patients is further complicated by increased susceptibility to brain hypoperfusion with orthostatic hypotension as well as the risk of drug–drug interactions. We recommend a systolic blood pressure goal of <140 mmHg in patients less than 80 years of age and a systolic blood pressure goal of 140–150 mmHg in patients 80 years of age or older. Reduction of blood pressure is probably more important than the specific agent used and initiation of drug therapy with an angiotensin converting enzyme inhibitor, angiotensin receptor blocker, calcium channel blocker, or diuretic are all reasonable options, and the decision should be individualized based on underlying comorbidities.

A review of the mechanisms and effectiveness of dietary polyphenols in reducing oxidative stress and thrombotic risk

Dietary sources of polyphenols, which are derivatives and/or isomers of flavones, isoflavones, flavonols, catechins and phenolic acids, possess antioxidant properties and therefore might be important in preventing oxidative-stress-induced platelet activation and attenuating adverse haemostatic function. Free radicals, including reactive oxygen and nitrogen species, promote oxidative stress, leading to platelet hyperactivation and the risk of thrombosis. The consumption of antioxidant/polyphenol rich foods might therefore impart anti-thrombotic and cardiovascular protective effects via their inhibition of platelet hyperactivation or aggregation. Most commonly-used anti-platelet drugs such as aspirin block the cyclooxygenase (COX)-1 pathway of platelet activation, similar to the action of antioxidants with respect to neutralising hydrogen peroxide (H2 O2 ), with a similar effect on thromboxane production via the COX-1 pathway. Polyphenols also target various additional platelet activation pathways (e.g. by blocking platelet-ADP, collagen receptors); thus alleviating fibrinogen binding to platelet surface (GPIIb-IIIa) receptors, reducing further platelet recruitment for aggregation and inhibiting platelet degranulation. As a result of the ability of polyphenols to target additional pathways of platelet activation, they may have the potential to substitute or complement currently used anti-platelet drugs in sedentary, obese, pre-diabetic or diabetic populations who can be resistant or sensitive to pharmacological anti-platelet therapy.

Study design of ASPirin in Reducing Events in the Elderly (ASPREE): a randomized, controlled trial

Cost-effective strategies to maintain healthy active lifestyle in aging populations are required to address the global burden of age-related diseases. ASPREE will examine whether the potential primary prevention benefits of low dose aspirin outweigh the risks in older healthy individuals. Our primary hypothesis is that daily oral 100 mg enteric-coated aspirin will extend a composite primary endpoint termed 'disability-free life' including onset of dementia, total mortality, or persistent disability in at least one of the Katz Activities of Daily Living in 19,000 healthy participants aged 65 years and above ('US minorities') and 70 years and above (non-'US minorities'). ASPREE is a double-blind, randomized, placebo-controlled trial of oral 100mg enteric-coated acetyl salicylic acid (ASA) or matching placebo being conducted in Australian and US community settings on individuals free of dementia, disability and cardiovascular disease (CVD) events. Secondary endpoints are all-cause and cause specific mortality, fatal and non-fatal cardiovascular events, fatal and non-fatal cancer (excluding non-melanoma skin cancer), dementia, mild cognitive impairment, depression, physical disability, and clinically significant bleeding. To 20 September 2013 14,383 participants have been recruited. Recruitment and study completion are anticipated in July 2014 and December 2018 respectively. In contrast to other aspirin trials that have largely focused on cardiovascular endpoints, ASPREE has a unique composite primary endpoint to better capture the overall risk and benefit of aspirin to extend healthy independent lifespan in older adults in the US and Australia.

Vitamin E serum levels and bleeding risk in patients receiving oral anticoagulant therapy: a retrospective cohort study

Background

Hemorrhagic risk assessment is a crucial issue in patients with nonvalvular atrial fibrillation (NVAF) who are receiving oral anticoagulant therapy (OAT). Our aim was to analyze the relationship between vitamin E, which possesses anticoagulant properties, and bleeding events in NVAF patients.

Methods and Results

In this retrospective observational study we analyzed baseline serum cholesterol‐adjusted vitamin E (vit E/chol) levels in 566 consecutive patients (59% males, mean age 73.6 years) receiving OAT followed up for a mean time of 22 months. Mean time in therapeutic INR range (TTR) was 64%. The overall incidence rate of any bleeding event was 9.2/100 person‐years. Compared to patients who did not bleed, those who experienced bleeding events (n=92, 73 minor and 15 major bleedings and 4 cerebral hemorrhages according to International Society on Thrombosis and Haemostasis [ISTH] ) classification) showed a significant difference for history of coronary heart disease (P=0.039), HAS‐BLED score (P=0.002), and vit E/chol levels (P<0.001). Higher vit E/chol serum levels were found in patients who bled compared to those who did not (5.27±1.93 versus 4.48±1.97 μmol/cholesterol; P<0.001), with a progressive increase from minor (5.16±1.91 μmol/mmol cholesterol, P=0.006) to major bleedings (5.72±2.0 μmol/mmol cholesterol, P=0.008). A Cox proportional hazard model demonstrated that serum vit E/chol quartiles (global P=0.0189) and HAS‐BLED scores (P=0.005) predicted bleeding events.

Conclusions

In a NVAF population being treated with warfarin, serum vitamin E predicted hemorrhagic events. Further study is necessary to see if the relationship between serum levels of vitamin E and bleeding is still maintained with the use of new anticoagulants.

Clinical Trial Registration

URL: ClinicalTrials.gov. Unique identifier NCT01882114.

The role of oxidized low-density lipoproteins in atherosclerosis: the myths and the facts

The oxidative modification hypothesis of atherosclerosis, which assigns to oxidized low-density lipoproteins (LDLs) a crucial role in atherosclerosis initiation and progression, is still debated. This review examines the role played by oxidized LDLs in atherogenesis taking into account data derived by studies based on molecular and clinical approaches. Experimental data carried out in cellular lines and animal models of atherosclerosis support the proatherogenic role of oxidized LDLs: (a) through chemotactic and proliferating actions on monocytes/macrophages, inciting their transformation into foam cells; (b) through stimulation of smooth muscle cells (SMCs) recruitment and proliferation in the tunica intima; (c) through eliciting endothelial cells, SMCs, and macrophages apoptosis with ensuing necrotic core development. Moreover, most of the experimental data on atherosclerosis-prone animals benefiting from antioxidant treatment points towards a link between oxidative stress and atherosclerosis. The evidence coming from cohort studies demonstrating an association between oxidized LDLs and cardiovascular events, notwithstanding some discrepancies, seems to point towards a role of oxidized LDLs in atherosclerotic plaque development and destabilization. Finally, the results of randomized clinical trials employing antioxidants completed up to date, despite demonstrating no benefits in healthy populations, suggest a benefit in high-risk patients. In conclusion, available data seem to validate the oxidative modification hypothesis of atherosclerosis, although additional proofs are still needed.

Molecular aspects of the cardioprotective effect of exercise in the elderly

Aging is a well-recognized risk factor for several different forms of cardiovascular disease. However, mechanisms by which aging exerts its negative effect on outcome have been only partially clarified. Numerous evidence indicate that aging is associated with alterations of several mechanisms whose integrity confers protective action on the heart and vasculature. The present review aims to focus on the beneficial effects of exercise, which plays a pivotal role in primary and secondary prevention of cardiovascular diseases, in counteracting age-related deterioration of protective mechanisms that are crucially involved in the homeostasis of cardiovascular system. In this regard, animal and human studies indicate that exercise training is able: (1) to improve the inotropic reserve of the aging heart through restoration of cardiac β-adrenergic receptor signaling; (2) to rescue the mechanism of cardiac preconditioning and angiogenesis whose integrity has been shown to confer cardioprotection against ischemia and to improve post-myocardial infarction left ventricular remodeling; (3) to counteract age-related reduction of antioxidant systems that is associated to decreased cellular resistance to reactive oxygen species accumulation. Moreover, this review also describes the molecular effects induced by different exercise training protocols (endurance vs. resistance) in the attempt to better explain what kind of exercise strategy could be more efficacious to improve cardiovascular performance in the elderly population.

Cardiovascular Pharmacology Core Reviews

Acetylsalicylic acid, or aspirin, is perhaps the most well-studied drug in human history, but controversy persists regarding both optimal dose and its use in the primary prevention of atherothrombotic events. This article reviews the following: the effect of aspirin upon the cyclooxygenase pathway; clinical trials of aspirin for both secondary and primary prevention; prospective and retrospective studies of aspirin dose; the potential interaction between aspirin and ticagrelor; and the concept of aspirin resistance. It concludes with a review of major society guidelines regarding aspirin and offers a perspective on the evidence-based use of aspirin in clinical practice.

Meta-regression analyses, meta-analyses, and trial sequential analyses of the effects of supplementation with beta-carotene, vitamin A, and vitamin E singly or in different combinations on all-cause mortality: do we have evidence for lack of harm?

Background and Aims

Evidence shows that antioxidant supplements may increase mortality. Our aims were to assess whether different doses of beta-carotene, vitamin A, and vitamin E affect mortality in primary and secondary prevention randomized clinical trials with low risk of bias.

Methods

The present study is based on our 2012 Cochrane systematic review analyzing beneficial and harmful effects of antioxidant supplements in adults. Using random-effects meta-analyses, meta-regression analyses, and trial sequential analyses, we examined the association between beta-carotene, vitamin A, and vitamin E, and mortality according to their daily doses and doses below and above the recommended daily allowances (RDA).

Results

We included 53 randomized trials with low risk of bias (241,883 participants, aged 18 to 103 years, 44.6% women) assessing beta-carotene, vitamin A, and vitamin E. Meta-regression analysis showed that the dose of vitamin A was significantly positively associated with all-cause mortality. Beta-carotene in a dose above 9.6 mg significantly increased mortality (relative risk (RR) 1.06, 95% confidence interval (CI) 1.02 to 1.09, I² = 13%). Vitamin A in a dose above the RDA (> 800 µg) did not significantly influence mortality (RR 1.08, 95% CI 0.98 to 1.19, I² = 53%). Vitamin E in a dose above the RDA (> 15 mg) significantly increased mortality (RR 1.03, 95% CI 1.00 to 1.05, I² = 0%). Doses below the RDAs did not affect mortality, but data were sparse.

Conclusions

Beta-carotene and vitamin E in doses higher than the RDA seem to significantly increase mortality, whereas we lack information on vitamin A. Dose of vitamin A was significantly associated with increased mortality in meta-regression. We lack information on doses below the RDA.

Background

All essential compounds to stay healthy cannot be synthesized in our body. Therefore, these compounds must be taken through our diet or obtained in other ways [1]. Oxidative stress has been suggested to cause a variety of diseases [2]. Therefore, it is speculated that antioxidant supplements could have a potential role in preventing diseases and death. Despite the fact that a normal diet in high-income countries may provide sufficient amounts of antioxidants [3,4], more than one third of adults regularly take antioxidant supplements [5,6].

Cardiovascular and upper gastrointestinal bleeding consequences of low-dose acetylsalicylic acid discontinuation

It was the aim of this study to investigate whether low-dose acetylsalicylic acid (ASA) therapy for secondary cardiovascular prevention should continue, despite the risk of gastrointestinal bleeding. We aimed to make a clinically meaningful benefit-risk assessment regarding the cardiovascular and gastrointestinal consequences of ASA discontinuation.This case-control study usedThe Health Improvement Network UK primary care database to identify patients aged 50-84 years during 2000-2007 with a first ASA prescription for secondary cardiovascular prevention (N = 39,513). New cases of non-fatal myocardial infarction (MI)/coronary death (n = 1,222), ischaemic stroke (IS)/transient ischaemic attack (TIA) (n = 673) and upper gastrointestinal bleeding (UGIB) (n = 169) were identified after a mean follow-up of 3.2, 3.4 and 4.0 years, respectively. ASA discontinuers before the index date were identified. Attributable risks associated with ASA discontinuation were calculated and National Institute for Health and Clinical Excellence annual economic data were used to estimate healthcare costs. The cumulative incidences of non-fatal MI/coronary death, IS/TIA and UGIB among ASA discontinuers within the first year of follow-up were 17, 11 and 1.6 per 1,000 persons, respectively. This corresponds to eight extra cardiovascular events, and a reduction of 0.4 UGIB events per year compared with current ASA users. Extrapolating to the UK population aged over 50 years, avoiding discontinuation of ASA could prevent 12,786 coronary and 7,672 cerebrovascular events/year, at the expense of 1023 extra UGIB events, saving approximately £100 million/year. In conclusion, preventing patients with cardiovascular disease from discontinuing ASA could result in substantial clinical and economic gains.

Vitamin E in the prevention of cardiovascular disease: the importance of proper patient selection

Vitamin E is a naturally occurring fat-soluble antioxidant which has been proposed as a treatment for both primary and secondary protection against cardiovascular (CV) events. Promising data from observational epidemiological studies associating higher vitamin E dietary intake with lower risk of CV events have not been validated in randomized controlled clinical trials assessing the effect of vitamin E on CV outcomes. While the pendulum of medical opinion has swung to suggest that high dose vitamin E supplements have no place in the treatment and prevention of CV disease, new data is emerging that allows identification of a specific target population for this treatment, namely patients with diabetes mellitus and the haptoglobin genotype 2-2. This review details the scientific basis and clinical evidence related to the effect of vitamin E on CV outcomes, and the importance of proper patient selection in gaining therapeutic benefit from this intervention.

Patient selection and vitamin E treatment in diabetes mellitus

In diabetes, there is an increase in oxidative stress due to elevated glucose levels in the plasma. High glucose promotes glycosylation, of both plasma and cellular proteins, which particularly affects the endothelial-cell lining of the blood vessel wall and interferes with its normal function. Thus, diabetes mellitus patients suffer from a higher incidence of cardiovascular complications such as atherosclerosis as compared with the nondiabetic population. Haptoglobin (Hp) is a plasma protein that binds free hemoglobin and prevents heme-iron mediated oxidation. There are three different types of Hp, which differ in their antioxidant ability. Several clinical studies have shown that the Hp 2-2 genotype is associated with higher incidence of cardiovascular diseases among diabetics. Vitamin E, a low-cost, easy-to-use antioxidant, was found to decrease the risk of developing cardiovascular diseases in Hp 2-2 diabetic patients. This review summarizes several studies that show the importance of vitamin E supplementation in a specific subgroup of patients, diabetic individuals carrying the Hp 2-2 genotype.

Plasma and dietary antioxidant status as cardiovascular disease risk factors: a review of human studies

Extensive evidence has demonstrated that many antioxidants such as vitamin C, vitamin E, carotenoids and polyphenols have protective effects in preventing cardiovascular disease (CVD), a chronic disease that is mediated by oxidative stress and inflammation. This review focuses on evidence from prospective cohort studies and clinical trials in regard to the associations between plasma/dietary antioxidants and cardiovascular events. Long-term, large-scale, population-based cohort studies have found that higher levels of serum albumin, bilirubin, glutathione, vitamin E, vitamin C, and carotenoids were associated with a lower risk of CVD. Evidence from the cohort studies in regard to dietary antioxidants also supported the protective effects of dietary vitamin E, vitamin C, carotenoids, and polyphenols on CVD risk. However, results from large randomized controlled trials did not support long-term use of single antioxidant supplements for CVD prevention due to their null or even adverse effects on major cardiovascular events or cancer. Diet quality indexes that consider overall diet quality rather than single nutrients have been drawing increasing attention. Cohort studies and intervention studies that focused on diet patterns such as high total antioxidant capacity have documented protective effects on CVD risk. This review provides a perspective for future studies that investigate antioxidant intake and risk of CVD.

Molecular basis of cardioprotective effect of antioxidant vitamins in myocardial infarction

Acute myocardial infarction (AMI) is the leading cause of mortality worldwide. Major advances in the treatment of acute coronary syndromes and myocardial infarction, using cardiologic interventions, such as thrombolysis or percutaneous coronary angioplasty (PCA) have improved the clinical outcome of patients. Nevertheless, as a consequence of these procedures, the ischemic zone is reperfused, giving rise to a lethal reperfusion event accompanied by increased production of reactive oxygen species (oxidative stress). These reactive species attack biomolecules such as lipids, DNA, and proteins enhancing the previously established tissue damage, as well as triggering cell death pathways. Studies on animal models of AMI suggest that lethal reperfusion accounts for up to 50% of the final size of a myocardial infarct, a part of the damage likely to be prevented. Although a number of strategies have been aimed at to ameliorate lethal reperfusion injury, up to date the beneficial effects in clinical settings have been disappointing. The use of antioxidant vitamins could be a suitable strategy with this purpose. In this review, we propose a systematic approach to the molecular basis of the cardioprotective effect of antioxidant vitamins in myocardial ischemia-reperfusion injury that could offer a novel therapeutic opportunity against this oxidative tissue damage.

The aspirin controversy in primary prevention

PURPOSE OF REVIEW

Apparently conflicting meta-analysis results have led to renewed debate about the role of aspirin for the primary prevention of cardiovascular disease. We review the results of meta-analyses comparing aspirin with placebo or no aspirin for the primary prevention of cardiovascular disease and critically evaluate whether aspirin provides a net benefit.

RECENT FINDINGS

The results of four independently conducted meta-analyses between 2009 and 2012 involving between 95 000 and 102 621 individuals at low risk of cardiovascular disease are consistent with the results of the 2002 Antithrombotic Trialists' Collaboration meta-analysis, which found that aspirin reduces cardiovascular events primarily by reducing nonfatal myocardial infarction (MI). There is no convincing evidence that aspirin reduces cardiovascular mortality, but estimates from all of the meta-analyses suggest a modest reduction in all-cause mortality. Aspirin reduces ischaemic stroke but increases haemorrhagic stroke and major bleeding.

SUMMARY

The meta-analysis results consistently indicate that, in individuals at low risk for cardiovascular disease, aspirin reduces the risk of MI at the cost of an increase in major bleeding and produces a modest nominally significant reduction in total mortality. These results suggest that recommendations for primary prevention with aspirin should be individualized, taking into account the balance between benefits and risks and individual values and preferences.

Aspirin Half Maximal Inhibitory Concentration Value on Platelet Cyclooxygenase1 in Severe Type-2 Diabetes Mellitus is not Significantly Different from that of Healthy Individuals

It is implicated that diabetic patients are more resistant to aspirin therapy than patients with other diseases or healthy individuals. We evaluated the inhibitory effects of aspirin on aggregation and the cyclooxygenase activity of platelets of 10 patients with severe type-2 diabetes mellitis (DM) and compared the results with those of healthy individuals. Although platelet aggregation had a tendency to be more resistant to aspirin with the DM group, there was no significant difference in half maximal inhibitory concentration 50 values of aspirin on the cyclooxygenase activity between the patients with DM and healthy individuals. Thus, the residual platelet aggregability uninhibited by aspirin appears to be independent of the cyclooxygenase activity. Since adenosine diphosphate (ADP) receptor blocking almost completely inhibited the residual platelet aggregability, it is suggested that hyperreactivity to ADP is more prevalent in patients with DM.

n-3 fatty acids in patients with multiple cardiovascular risk factors

BACKGROUND

Trials have shown a beneficial effect of n-3 polyunsaturated fatty acids in patients with a previous myocardial infarction or heart failure. We evaluated the potential benefit of such therapy in patients with multiple cardiovascular risk factors or atherosclerotic vascular disease who had not had a myocardial infarction.

METHODS

In this double-blind, placebo-controlled clinical trial, we enrolled a cohort of patients who were followed by a network of 860 general practitioners in Italy. Eligible patients were men and women with multiple cardiovascular risk factors or atherosclerotic vascular disease but not myocardial infarction. Patients were randomly assigned to n-3 fatty acids (1 g daily) or placebo (olive oil). The initially specified primary end point was the cumulative rate of death, nonfatal myocardial infarction, and nonfatal stroke. At 1 year, after the event rate was found to be lower than anticipated, the primary end point was revised as time to death from cardiovascular causes or admission to the hospital for cardiovascular causes.

RESULTS

Of the 12,513 patients enrolled, 6244 were randomly assigned to n-3 fatty acids and 6269 to placebo. With a median of 5 years of follow-up, the primary end point occurred in 1478 of 12,505 patients included in the analysis (11.8%), of whom 733 of 6239 (11.7%) had received n-3 fatty acids and 745 of 6266 (11.9%) had received placebo (adjusted hazard ratio with n-3 fatty acids, 0.97; 95% confidence interval, 0.88 to 1.08; P=0.58). The same null results were observed for all the secondary end points.

CONCLUSIONS

In a large general-practice cohort of patients with multiple cardiovascular risk factors, daily treatment with n-3 fatty acids did not reduce cardiovascular mortality and morbidity. (Funded by Società Prodotti Antibiotici and others; ClinicalTrials.gov number, NCT00317707.).

Reactive oxygen species and the cardiovascular system

Ever since the discovery of free radicals, many hypotheses on the deleterious actions of reactive oxygen species (ROS) have been proposed. However, increasing evidence advocates the necessity of ROS for cellular homeostasis. ROS are generated as inherent by-products of aerobic metabolism and are tightly controlled by antioxidants. Conversely, when produced in excess or when antioxidants are depleted, ROS can inflict damage to lipids, proteins, and DNA. Such a state of oxidative stress is associated with many pathological conditions and closely correlated to oxygen consumption. Although the deleterious effects of ROS can potentially be reduced by restoring the imbalance between production and clearance of ROS through administration of antioxidants (AOs), the dosage and type of AOs should be tailored to the location and nature of oxidative stress. This paper describes several pathways of ROS signaling in cellular homeostasis. Further, we review the function of ROS in cardiovascular pathology and the effects of AOs on cardiovascular outcomes with emphasis on the so-called oxidative paradox.

The aspirin cardiovascular/gastrointestinal risk calculator--a tool to aid clinicians in practice

BACKGROUND

Assessment of both GI and CV risks vs. the benefits of low-dose aspirin for individual patients can be difficult in clinical practice.

AIM

To develop a tool to estimate CV and GI risks to facilitate the clinical decision-making process.

METHODS

We constructed risk-ratio estimations and determined the incidence of CV events and upper GI complications according to the presence of different risk factors. For upper GI complications we assumed a baseline incidence of 1 case/1000-persons-year, a twofold increased risk with low-dose aspirin, and estimated a 60% GI risk reduction with proton pump inhibitors (PPI) co-therapy and a 60% risk reduction with H. pylori eradication in patients with a history of peptic ulcer.

RESULTS

The calculator can be found at http://www.asariskcalculator.com. In patients with low CV risk the number of GI complications induced by low-dose aspirin may be greater than the number of CV events prevented. In patients with high CV risk, low-dose aspirin is recommended, but the number of GI complications induced may still overcome the CV events saved. The use of PPI reduces the number of complication events induced by low-dose aspirin, but the number of CV events saved may still be offset by the number of GI complications induced in patients at very high GI risk.

CONCLUSIONS

There are many clinical situations where the number of potential upper GI complications induced by low-dose aspirin may exceed the number of potentially prevented CV events. A risk calculator should guide physicians in choosing appropriate therapy and maximise the aspirin benefit.

Reinitiating aspirin therapy for primary prevention of cardiovascular events in a patient post-aspirin-induced upper gastrointestinal bleed: a case report and review of literature

OBJECTIVE

To describe a case of continued aspirin use for primary prevention of a cardiovascular event in a patient post-aspirin-induced upper gastrointestinal (GI) bleed and evaluate published evidence to determine whether reinitiating aspirin therapy for this patient was appropriate.

CASE SUMMARY

A 65-year-old man had been taking chronic low-dose (81 mg/day) aspirin therapy since 2002 for primary prevention of a cardiovascular event. He developed an upper GI bleed with lowered hemoglobin (9 mg/dL) and hematocrit (26.3%) after concomitantly taking 2 doses of naproxen (220 mg each). An objective causality assessment with the Naranjo probability scale revealed a probable adverse reaction of an upper GI bleed associated with concomitant naproxen and aspirin use. No further naproxen was taken. Aspirin was discontinued and pantoprazole was started, with resolution of the bleeding. Aspirin was restarted 2.5 months after pantoprazole was initiated, and no further bleeding occurred.

DISCUSSION

Upper GI bleeds associated with aspirin therapy are well described in the literature. The management of cardiovascular event prophylaxis after a GI bleed is often controversial; consensus in regard to the optimal method of management does not exist. We evaluated GI protection strategies for patients with a history of aspirin-induced GI bleeding requiring cardiovascular prophylaxis. We found that the benefit of aspirin for the primary prevention of cardiovascular events needs to be carefully balanced with the risks associated with its use. The current literature supports that the best approach to prevent recurrent aspirin-induced GI bleeding is to administer a proton pump inhibitor with aspirin therapy.

CONCLUSIONS

The benefit of aspirin for primary prevention of cardiovascular events needs to be carefully balanced with the risks associated with its use. Based on the current literature, the best approach to preventing recurrent aspirin-induced GI bleeds is to administer a proton pump inhibitor concomitantly with aspirin therapy.

Efficacy of vitamin and antioxidant supplements in prevention of cardiovascular disease: systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To assess the efficacy of vitamin and antioxidant supplements in the prevention of cardiovascular diseases.

DESIGN

Meta-analysis of randomised controlled trials.

DATA SOURCES AND STUDY SELECTION

PubMed, EMBASE, the Cochrane Library, Scopus, CINAHL, and ClinicalTrials.gov searched in June and November 2012. Two authors independently reviewed and selected eligible randomised controlled trials, based on predetermined selection criteria.

RESULTS

Out of 2240 articles retrieved from databases and relevant bibliographies, 50 randomised controlled trials with 294,478 participants (156,663 in intervention groups and 137,815 in control groups) were included in the final analyses. In a fixed effect meta-analysis of the 50 trials, supplementation with vitamins and antioxidants was not associated with reductions in the risk of major cardiovascular events (relative risk 1.00, 95% confidence interval 0.98 to 1.02; I(2)=42%). Overall, there was no beneficial effect of these supplements in the subgroup meta-analyses by type of prevention, type of vitamins and antioxidants, type of cardiovascular outcomes, study design, methodological quality, duration of treatment, funding source, provider of supplements, type of control, number of participants in each trial, and supplements given singly or in combination with other supplements. Among the subgroup meta-analyses by type of cardiovascular outcomes, vitamin and antioxidant supplementation was associated with a marginally increased risk of angina pectoris, while low dose vitamin B(6) supplementation was associated with a slightly decreased risk of major cardiovascular events. Those beneficial or harmful effects disappeared in subgroup meta-analysis of high quality randomised controlled trials within each category. Also, even though supplementation with vitamin B(6) was associated with a decreased risk of cardiovascular death in high quality trials, and vitamin E supplementation with a decreased risk of myocardial infarction, those beneficial effects were seen only in randomised controlled trials in which the supplements were supplied by the pharmaceutical industry.

CONCLUSION

There is no evidence to support the use of vitamin and antioxidant supplements for prevention of cardiovascular diseases.