Low-Dose Aspirin for Primary Prevention of Cardiovascular Events in Patients With Diabetes: A Meta-Analysis

Interventions for primary prevention of cardiovascular disease: umbrella review of systematic reviews

Background

Cardiovascular diseases are the leading cause of death globally. The aim of this overview of systematic reviews was to compare the effectiveness of different pharmacological and non-pharmacological interventions for the primary prevention of cardiovascular disease.

Methods

A structured search of the Cochrane Database of Systematic Reviews, MEDLINE, EMBASE and the Database of Abstracts of Reviews of Effects archive was conducted to find systematic reviews that reported the effect of various pharmacological and non-pharmacological interventions for the primary prevention of cardiovascular disease from inception to March 2021. References of included studies were also checked. The included systematic reviews' methodological quality was assessed using the Assessment of Multiple Systematic Reviews 2 instrument (range, 0-16). The outcomes of each included review's meta-analysis were extracted and described narratively.

Results

This study analysed 95 systematic reviews, including 41 on non-pharmacological interventions and 54 on pharmacological interventions for cardiovascular health. The majority of the reviews focused on lipid-lowering interventions (n = 25) and antiplatelet medications (n = 21), followed by nutritional supplements, dietary interventions, physical activity, health promotion and other interventions. Only 1 of the 10 reviews addressing cardiovascular mortality showed a potential benefit, while the others found no effect. Antiplatelets were found to have a beneficial effect on all-cause mortality in 2 out of 12 meta-analyses and on major cardiovascular disease events in 8 out of 17 reviews. Lipid-lowering interventions showed beneficial effects on cardiovascular disease mortality, all-cause mortality and major cardiovascular disease events in varying numbers of the reviews. Glucose-lowering medications demonstrated significant benefits for major cardiovascular events, coronary heart disease events and mortality. However, the combination of dietary interventions, physical activities, nutritional supplements and polypills showed little or no significant benefit for major cardiovascular outcomes or mortality.

Future work and limitations

More research is needed to determine whether the effect of treatment varies depending on population characteristics. The findings of this review should be interpreted with caution because the majority of studies of non-pharmacological interventions compare primary prevention with usual care, which may include recommended pharmacological treatment in higher-risk patients (e.g. statins and/or antihypertensive medications, etc.). In addition, randomised controlled trial evidence may be better suited to the study of pharmacological interventions than dietary and lifestyle interventions.

Conclusions

This umbrella review captured the variability in different interventions on randomised controlled trial evidence on interventions for primary prevention of cardiovascular disease and identified areas that may benefit from further research. Specifically, this review focused on randomised controlled trial evidence on interventions for primary prevention of cardiovascular disease. Researchers may use these findings as a resource to direct new intervention studies and network meta-analyses to compare the efficacy of various interventions based on these findings.

Funding

This article presents independent research funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment (HTA) programme as award number 17/148/05.

Evaluating the Efficacy and Safety of Aspirin for Primary Cardiovascular Prevention in Asian Patients with Type 2 Diabetes: A Population-Based and Propensity Score-Matched Study

The risk of developing cardiovascular disease is significantly higher for individuals with diabetes compared to those without. Aspirin has been widely used for primary prevention in diabetic patients. However, evidence is limited in the Asian population. We aimed to compare the effectiveness and safety of aspirin versus placebo for primary cardiovascular prevention in the Asian population with type 2 diabetes. In this study, we performed propensity score matching with non-aspirin users from January 2006 to December 2015 (n = 37,095 in each group after matching, PSM). We analyzed the incidence risk of all-cause mortality, composite cardiovascular events, and hospitalized major bleeding. The propensity score-matched (PSM) cohort of patients who received aspirin within one year of diabetes diagnosis was compared with the non-aspirin diabetic (DM) cohort. Baseline characteristics were balanced between the two groups. The median follow-up duration was 78 months. Aspirin users exhibited a slightly but significantly lower rate of all-cause mortality (HR: 0.92; 95% CI: 0.87 to 0.96). However, they also had a significantly higher composite cardiovascular risk (HR: 1.34; 95% CI: 1.28-1.40), including non-fatal acute myocardial infarction (HR: 1.33; 95% CI: 1.18 to 1.50), non-fatal ischemic stroke (HR: 1.38; 95% CI: 1.30 to 1.45), heart failure (HR: 1.18; 95% CI: 1.09 to 1.27), and coronary revascularization (HR: 1.94; 95% CI: 1.73 to 2.17). Aspirin users also faced a significantly higher risk of hospitalized major bleeding (HR: 1.08; 95% CI: 1.03 to 1.14). The presence of one or more additional risk factors did not influence the effectiveness and safety outcomes of aspirin, according to stratified analysis. In conclusion, in this real-world Asian diabetic population, aspirin was associated with a significantly lower mortality risk but also with higher risks of cardiovascular events and hospitalized bleeding. Aspirin may not play a role in the primary prevention of cardiovascular disease in such patients, regardless of additional risk factors.

Evaluation of prophylaxis in primary prevention with acetylsalicylic acid in people with diabetes: A scoping review

BACKGROUND

The efficacy and safety of acetylsalicylic acid (ASA) prophylaxis for the primary prevention of atherosclerotic cardiovascular disease (ACVD) remain controversial in people with diabetes (DM) without ACVD, because the possible increased risk of major bleeding could outweigh the potential reduction in the risk of mortality and of major adverse cardiovascular events (MACE) considered individually or together.

OBJECTIVE

To evaluate the overall risk-benefit of ASA prophylaxis in primary prevention in people with DM and to compare the recommendations of the guidelines with the results of the meta-analyses (MA) and systematic reviews (SR).

MATERIAL AND METHODS

We searched Medline, Google Scholar, Embase, and the Cochrane Library for SR and MA published from 2009 to 2020 which compared the effects of ASA prophylaxis versus placebo or control followed up for at least one year in people with DM without ACVD. Heterogeneity among the randomized clinical trials (RCT) included in the SR and MA was assessed. Cardiovascular outcomes of efficacy (all-cause mortality [ACM], cardiovascular mortality [CVM], myocardial infarction [MI], stroke and MACE) and of safety (major bleeding events [MBE], major gastrointestinal bleeding events [MGIBE], and intracranial and extracranial bleeding) were shown.

RESULTS

The recommendations of 12 guidelines were evaluated. The results of 25 SR and MA that included a total of 20 RCT were assessed. None of the MA or SR showed that ASA prophylaxis decreased the risk of ACM, CVM or MI. Only two of the 19 SR and MA that evaluated ischemic stroke showed a decrease in the stroke risk (mean 20.0% [SD±5.7]), bordering on statistical significance. Almost half of the MA and SR showed, bordering on statistical significance, a risk reduction for the MACE composite endpoint (mean 10.5% [SD±3.3]). The significant increases in MGIBE risk ranged from 35% to 55%. The significant increases in the risk of MBE and extracraneal bleeding were 33.4% (SD±14.9) and 54.5% (SD±0.7) respectively.

CONCLUSION

The overall risk-benefit assessment of ASA prophylaxis in primary prevention suggests that it should not be applied in people with DM.

[Cardiovascular preventive recommendations. PAPPS 2020 update]

The recommendations of the semFYC's Program for Preventive Activities and Health Promotion (PAPPS) for the prevention of cardiovascular diseases (CVD) are presented. The following sections are included: Epidemiological review, where the current morbidity and mortality of CVD in Spain and its evolution as well as the main risk factors are described; Cardiovascular (CV) risk tables and recommendations for the calculation of CV risk; Main risk factors such as arterial hypertension, dyslipidemia and diabetes mellitus, describing the method for their diagnosis, therapeutic objectives and recommendations for lifestyle measures and pharmacological treatment; Indications for antiplatelet therapy, and recommendations for screening of atrial fibrillation. The quality of testing and the strength of the recommendation are included in the main recommendations.

Recommendation of Aspirin-Guide App and Physicians Clinical Decision of Aspirin Use to Prevent CVD Among Diabetic Patients, Is there any Differences?

OBJECTIVE

This study aims to identify the prevalence of aspirin use among type 2 diabetic (T2DM) patients and assess the concordance in aspirin use among these patients as prescribed by physicians and as recommended by the Aspirin-Guide app.

METHODS

A total of 301 T2DM patients from King Khalid University Hospital in Riyadh, Saudi Arabia participated in this cross-sectional study. Patient's electronic medical records through eSihi system were reviewed and all data included in the free online and mobile app called Aspirin-Guide were collected in a specially designed data checklist.

RESULT

The prevalence of aspirin use was more common in patients who were in the age group of 51 to 59 and male participants' with T2DM. Males were nearly twice more likely to use aspirin compared to females (P = 0.001). Based on recommendations from the Aspirin-Guide app, 26% of the patients who were on aspirin (N = 51) were not eligible for aspirin therapy, while 37.7% (N = 40) of the patients eligible for aspirin therapy had not been put on aspirin by their physicians (P = 0.039). Male sex (P = 0.003), use of statins (P = 0.001), and being advised to use aspirin (P = 0.041), were significantly associated with aspirin use in T2DM patients.

CONCLUSION

There was a significant difference in the proportion of patients currently on aspirin as prescribed by their physicians and those eligible for aspirin therapy as per the Aspirin-Guide app. The use of an app to uniformized aspirin use among eligible patients should be based on up-to-date guidelines and account for patient acceptability and willingness to commence treatment.

Low-Dose Aspirin for the Primary Prevention of Cardiovascular Disease in Diabetic Individuals: A Meta-Analysis of Randomized Control Trials and Trial Sequential Analysis

Background: Evidence of low-dose aspirin as the primary prevention strategy for cardiovascular disease (CVD) in diabetes are unclear. This study was designed to evaluate the effect of low-dose aspirin use for the primary prevention of CVD in diabetes. Methods: We collected randomized controlled trials of low-dose aspirin for the primary prevention of CVD in adults with diabetes lasting at least 12 months from Medline, Embase, and the Cochrane Library up to 10 November 2018. Two reviewers extracted data and appraised the reporting quality according to a predetermined protocol (CRD4201811830). This review was conducted using Cochrane standards, trial sequential analysis, and the Grading of Recommendation. The primary outcomes were major adverse cardiovascular events (MACE, including non-fatal myocardial infarction, ischemia stroke, and cardiovascular death) and an incidence of major hemorrhage (major intracranial hemorrhage and major gastrointestinal bleeding). Results: In this primary prevention (number = 29,814 participants) meta-analysis, low-dose aspirin use reduced the risk of MACE by 9% and increased the risk of major hemorrhage by 24%. The benefits were only observed in subjects of age ≥ 60 years while reducing the same risk of MACE. In efficacy, it reduced the risk of stroke but not myocardial infarction. No increase in all-cause mortality or cardiovascular death was observed. Conclusions: We suggested the use of low-dose aspirin as the primary prevention strategy for CVD in diabetes, particularly in an older population. The absolute benefits were largely counterbalanced by the bleeding hazard.

Aspirin for Primary Cardiovascular Risk Prevention and Beyond in Diabetes Mellitus

Daily administration of low-dose aspirin has proved to be beneficial in preventing recurrent cardiovascular events. However, the role of aspirin for primary prevention in patients with no overt cardiovascular disease is more controversial. In fact, in lower risk patients, the modest benefit in reducing serious vascular events can be offset by the increased risk of bleeding, including intracranial and gastrointestinal hemorrhage. Diabetes mellitus has been associated with a substantially increased risk of both first and recurrent atherothrombotic events, which makes aspirin therapy of potential value in these subjects. Moving from general aspects of aspirin pharmacology and specific issues in diabetes mellitus, this article reviews the literature on the topic of aspirin for primary prevention in general, and in subjects with diabetes mellitus in particular, to culminate with arguments pro and con and a practical risk-based algorithm for aspirin initiation in daily practice.

Aspirin for primary prevention of cardiovascular disease in patients with diabetes: A meta-analysis

AIMS

Aspirin use for primary prevention of cardiovascular disease (CVD) is controversial, especially in patients with diabetes. The objective of this meta-analysis was to evaluate aspirin's safety and efficacy for primary prevention of CVD [fatal or nonfatal myocardial infarction (MI), fatal or nonfatal stroke, angina, transient ischemic attack (TIA), peripheral artery disease (PAD) and revascularization] in patients with diabetes.

METHODS

A literature search was conducted using the terms cardiovascular disease, aspirin, diabetes mellitus to identify trials of patients with diabetes who received aspirin for primary prevention of CVD. Study sample size, and ischemic and bleeding events were extracted and analyzed using RevMan 5.2.7.

RESULTS

In total, 6 studies (n=10,117) met criteria. Aspirin doses ranged from 100mg every other day to 650mg daily. Follow-up ranged from 3.6 to 10.1years. In patients with diabetes, there was no difference between aspirin and placebo with respect to the risk of all cause mortality (OR 0.93, 95% CI 0.81-1.06), or individual atherosclerotic events compared to placebo. There were no differences in bleeding (OR 2.53, 95% CI 0.77-8.34), GI bleeding (OR 2.14, 95% CI 0.63-7.33) or hemorrhagic stroke rates (OR 0.90, 0.34-2.33) between groups.

CONCLUSIONS

It remains unclear whether aspirin may reduce the occurrence of a first atherosclerotic event or mortality in patients with diabetes. More research on this use of aspirin in patients with diabetes is required to supplement currently available research.

Drugs for Primary Prevention of Atherosclerotic Cardiovascular Disease: An Overview of Systematic Reviews

IMPORTANCE

The Million Hearts initiative emphasizes ABCS (aspirin for high-risk patients, blood pressure [BP] control, cholesterol level management, and smoking cessation). Evidence of the effects of drugs used to achieve ABCS has not been synthesized comprehensively in the prevention of primary atherosclerotic cardiovascular disease (ASCVD).

OBJECTIVE

To compare the efficacy and safety of aspirin, BP-lowering therapy, statins, and tobacco cessation drugs for fatal and nonfatal ASCVD outcomes in primary ASCVD prevention.

EVIDENCE REVIEW

Structured search of the Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (DARE), Health Technology Assessment Database (HTA), MEDLINE, EMBASE, and PROSPERO International Prospective Systematic Review Trial Register to identify systematic reviews published from January 1, 2005, to June 17, 2015, that reported the effect of aspirin, BP-lowering therapy, statin, or tobacco cessation drugs on ASCVD events in individuals without prevalent ASCVD. Additional studies were identified by searching the reference lists of included systematic reviews, meta-analyses, and health technology assessment reports. Reviews were selected according to predefined criteria and appraised for methodologic quality using the Assessment of Multiple Systematic Reviews (AMSTAR) tool (range, 0-11). Studies were independently reviewed for key participant and intervention characteristics. Outcomes that were meta-analyzed in each included review were extracted. Qualitative synthesis was performed, and data were analyzed from July 2 to August 13, 2015.

FINDINGS

From a total of 1967 reports, 35 systematic reviews of randomized clinical trials were identified, including 15 reviews of aspirin, 4 reviews of BP-lowering therapy, 12 reviews of statins, and 4 reviews of tobacco cessation drugs. Methodologic quality varied, but 30 reviews had AMSTAR ratings of 5 or higher. Compared with placebo, aspirin (relative risk [RR], 0.90; 95% CI, 0.85-0.96) and statins (RR, 0.75; 95% CI, 0.70-0.81) reduced the risk for ASCVD. Compared with placebo, BP-lowering therapy reduced the risk for coronary heart disease (RR, 0.84; 95% CI, 0.79-0.90) and stroke (RR, 0.64; 95% CI, 0.56-0.73). Tobacco cessation drugs increased the odds of continued abstinence at 6 months (odds ratio range, 1.82 [95% CI, 1.60-2.06] to 2.88 [95% CI, 2.40-3.47]), but the direct effects on ASCVD were poorly reported. Aspirin increased the risk for major bleeding (RR, 1.54; 95% CI, 1.30-1.82), and statins did not increase overall risk for adverse effects (RR, 1.00; 95% CI, 0.97-1.03). Adverse effects of BP-lowering therapy and tobacco cessation drugs were poorly reported.

CONCLUSIONS AND RELEVANCE

This overview demonstrates high-quality evidence to support aspirin, BP-lowering therapy, and statins for primary ASCVD prevention and tobacco cessation drugs for smoking cessation. Treatment effects of each drug can be used to enrich discussions between health care professionals and patients in primary ASCVD prevention.

Temporal Trends and Outcomes of Patients Undergoing Percutaneous Coronary Interventions for Cardiogenic Shock in the Setting of Acute Myocardial Infarction: A Report From the CathPCI Registry

OBJECTIVES

The purpose of this study was to examine the temporal trends in demographics, clinical characteristics, management strategies, and in-hospital outcomes in patients with acute myocardial infarction complicated by cardiogenic shock (CS-AMI) who underwent percutaneous coronary intervention (PCI) from the Cath-PCI Registry (2005 to 2013).

BACKGROUND

The authors examined contemporary use and outcomes of PCI in patients with CS-AMI.

METHODS

The authors used the Cath-PCI Registry to evaluate 56,497 patients (January 2005 to December 2013) undergoing PCI for CS-AMI. Temporal trends in clinical variables and outcomes were assessed.

RESULTS

Compared with cases performed from 2005 to 2006, CS-AMI patients receiving PCI from 2011 to 2013 were more likely to have diabetes, hypertension, dyslipidemia, previous PCI, dialysis, but less likely to have chronic lung disease, peripheral vascular disease, or heart failure within 2 weeks (p < 0.01). Between 2005 and 2006 to 2011 and 2013, intra-aortic balloon pump use decreased (49.5% to 44.9%; p < 0.01), drug-eluting stent use declined (65% to 46%; p < 0.01), and the use of bivalirudin increased (12.6% to 45.6%). Adjusted in-hospital mortality; increased (27.6% in 2005 to 2006 vs. 30.6% in 2011 to 2013, adjusted odds ratio: 1.09, 95% confidence interval: 1.005 to .173; p = 0.04) for patients who were managed with an early invasive strategy (<24 h from symptoms).

CONCLUSIONS

Our study shows that despite the evolution of medical technology and use of contemporary therapeutic measures, in-hospital mortality in CS-AMI patients who are managed invasively continues to rise. Additional research and targeted efforts are indicated to improve outcomes in this high-risk cohort.

Aspirin in the prevention of cardiovascular events in patients with diabetes

Diabetes imparts a substantial increased risk for cardiovascular disease-related mortality and morbidity. Because of this, current medical guidelines recommend prophylactic treatment with once-daily, low-dose aspirin (acetylsalicylic acid) for primary and secondary prevention of cardiovascular (CV) events in high-risk patients. However, only modest reductions in CV events and mortality have been observed with once-daily aspirin treatment in patients with diabetes, including patients with a previous CV event, perhaps because of disparity between aspirin pharmacokinetics and diabetes-related platelet abnormalities. Once-daily aspirin irreversibly inactivates platelets for only a short duration (acetylsalicylic acid half-life, approximately 15-20 minutes), after which time newly generated, active platelets enter the circulation and weaken aspirin's effect. Platelets from patients with diabetes are more reactive and are turned over more rapidly than platelets from normal individuals; the short inhibitory window provided by once-daily aspirin may therefore be insufficient to provide 24-h protection against CV events. Alternative conventional aspirin regimens (e.g. higher daily dose, twice-daily dosing, combination with clopidogrel) and newer formulations (e.g. 24-h, extended-release) have been proposed to overcome the apparent limited efficacy of conventional aspirin in patients with diabetes; however, tolerability concerns and limited clinical efficacy data need to be taken into account when considering the use of such regimens.

Screening for Abnormal Blood Glucose and Type 2 Diabetes Mellitus: U.S. Preventive Services Task Force Recommendation Statement

DESCRIPTION

Update of the 2008 U.S. Preventive Services Task Force (USPSTF) recommendation on screening for diabetes in asymptomatic adults.

METHODS

The USPSTF reviewed the evidence on screening for impaired fasting glucose, impaired glucose tolerance, and type 2 diabetes in asymptomatic, nonpregnant adults who are at average or high risk for diabetes and its complications.

POPULATION

This recommendation applies to adults aged 40 to 70 years seen in primary care settings who do not have symptoms of diabetes and are overweight or obese.

RECOMMENDATION

The USPSTF recommends screening for abnormal blood glucose as part of cardiovascular risk assessment in adults aged 40 to 70 years who are overweight or obese. Clinicians should offer or refer patients with abnormal blood glucose to intensive behavioral counseling interventions to promote a healthful diet and physical activity. (B recommendation).

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.

Guidelines for the primary prevention of stroke: a statement for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated statement is to provide comprehensive and timely evidence-based recommendations on the prevention of stroke among individuals who have not previously experienced a stroke or transient ischemic attack. Evidence-based recommendations are included for the control of risk factors, interventional approaches to atherosclerotic disease of the cervicocephalic circulation, and antithrombotic treatments for preventing thrombotic and thromboembolic stroke. Further recommendations are provided for genetic and pharmacogenetic testing and for the prevention of stroke in a variety of other specific circumstances, including sickle cell disease and patent foramen ovale.

Contemporary treatment strategies for Type 2 diabetes-related macrovascular disease

Type 2 diabetes mellitus poses a major challenge to healthcare providers in the coming years as its prevalence increases across the globe. The disease doubles the risk of cardiovascular morbidity and mortality, with 70% of sufferers dying from a cardiac cause. Large clinical trials of current glucose-lowering therapies for Type 2 diabetes have shown no benefit in reducing the risk of macrovascular events. Blood pressure control, angiotensin-converting enzyme inhibitor therapy and improvement of dyslipidemia with statins have proven benefit in reducing cardiovascular risk in Type 2 diabetes. A growing understanding of the importance of pathological processes including endothelial dysfunction, abnormal growth factor biology, oxidative stress, dysregulation of adipokines and deficient vascular repair and regeneration in insulin-resistant states promises new treatments to combat the problem.

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.

Myocardial infarction and gastro-intestinal bleeding risks associated with aspirin use among elderly individuals with type 2 diabetes

INTRODUCTION

The benefit of aspirin in primary prevention of myocardial infarction and the associated gastro-intestinal bleeding risks have not been well established in the elderly population with diabetes.

METHODS

Using Quebec administrative databases, we conducted two nested case-control analyses within a cohort of individuals aged ≥ 66 years newly treated with an oral antidiabetes drug between 1998 and 2003. The 28,067 individuals had no cardiovascular disease recorded in the database in the year prior cohort entry. They had not used prescribed aspirin, antiplatelet, or anticoagulant drugs, and were not hospitalized for gastro-intestinal bleeding in the year prior cohort entry. The odds of myocardial infarction and gastro-intestinal bleedings were compared between individuals who were current, past, or non-users of aspirin.

RESULTS

There were 1101 (3.9%) cases of myocardial infarction. Compared to non-users, neither aspirin users (OR 0.89; 95% CI 0.71-1.13) nor aspirin past users (0.81; 0.62-1.06) showed a statistically significant lower risk of myocardial infarction. There were 373 (1.3%) cases of gastro-intestinal bleeding. Current users of aspirin had about a 2-fold greater risk of gastro-intestinal bleeding compared to non-users (2.19; 1.53-3.13).

CONCLUSIONS

Our results suggest that individual assessment of bleeding risk and cardiovascular risk is mandatory among elderly people with diabetes before introducing aspirin therapy.

Management of cardiovascular disease risk factors in older adults with type 2 diabetes mellitus: 2002-2012 literature review

Type 2 diabetes mellitus (DM) is one of the most common chronic conditions in older adults and is often accompanied by comorbidities and geriatric syndromes. The management of cardiovascular disease risk factors in older adults with DM is important to clinicians. The literature was reviewed from 2002 to 2012 to provide an American Geriatrics Society expert panel with an evidence base for updating and making new recommendations for improving the care of older adults with type 2 DM. This review includes only the domains of the management of blood pressure, lipid control, glycemic control, and use of aspirin. Over the last 10 years, new randomized controlled trials (RCT) designed to study different blood pressure treatment targets did not find evidence that intensive systolic blood pressure control (<130 mmHg) resulted in lower rates of myocardial infarction and mortality than less-intensive control. There are risks of side effects with achieving systolic blood pressure of less than 120 mmHg. Lipid-lowering statins are effective in reducing cardiovascular events in middle-aged and older adults, but data on niacin and fibrates is limited. Trials of statins and other lipid-lowering agents do not evaluate the cardiovascular effects on outcomes from treating lipids to different low-density lipoprotein cholesterol targets. No RCTs of lipid-lowering drugs enrolled significant numbers of adults aged 80 and older with or without DM. Three major RCTs that investigated intensive glycemic control did not find reductions in primary cardiovascular endpoints, and one study reported greater mortality with glycosylated hemoglobin of less than 6%. Two recently published RCTs were designed to study the cardiovascular benefits of aspirin use by individuals with DM. Neither trial found significantly fewer primary cardiovascular endpoints with aspirin than in control groups. Overall, RCTs enrolled few adults aged 80 and older or with significant comorbidities. More research is needed for clinicians to effectively customize care to older adults with DM because of heterogeneity in health status, comorbidities, duration of disease, frailty and functional status, and differences in life expectancy.

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.

Acetylsalicylic acid for primary prevention of cardiovascular diseases in older patients with diabetes: do the benefits overcome the risks?

Cardiovascular diseases (CVDs) represent a huge health burden for older patients with diabetes. Acetylsalicylic acid (ASA) has long been used as a cardioprotective agent in primary and secondary prevention of CVD. However, there are important issues regarding the benefits and risks of ASA therapy in primary prevention of CVDs, for the older group in general and for individuals of all ages with diabetes. In this review, we summarize the benefits and risks related to ASA therapy by outlining the evidence for older patients and for patients with diabetes. There appear to be significant gaps in knowledge. The balance of benefits and risks is not well defined but ASA treatment seems to be unfavorable in many older patients.

Aspirin for primary prevention of cardiovascular events in the elderly: current status and future directions

The role of aspirin in the secondary prevention of occlusive cardiovascular events has now been well established. Given this, aspirin in primary prevention has been the focus of several large trials and subsequent meta-analyses over the past 3 decades, and yet the issue remains controversial. Recent studies in populations with high baseline risk - such as diabetics and those with asymptomatic peripheral arterial disease - have not found the expected benefits of aspirin on cardiovascular endpoints, which contrasts with earlier studies that reported a reduced relative risk for outcomes such as myocardial infarction and ischaemic stroke, but not for mortality. Furthermore, in healthy populations, the absolute risk reduction conferred by aspirin is small and needs to be balanced against the risk of a major haemorrhage. Older adults have a higher risk for cardiovascular events and therefore might represent the group in which aspirin for primary prevention could deliver the greatest absolute benefit, yet at the same time, the elderly bear an increased vulnerability to major haemorrhage, including haemorrhagic stroke. It is also not known whether older adults experience the same risk reduction from aspirin as middle-aged individuals. The current evidence base does not sufficiently clarify whether aspirin for primary prevention confers a meaningful net benefit in the elderly.

Should diabetes still be considered a coronary artery disease equivalent?

Diabetes is well established as a cardiovascular risk factor and is currently regarded as a coronary artery disease equivalent. However, some recent data have contradicted the concept. We review the currently available data and usefulness or otherwise of this concept. While the concept of coronary artery disease equivalence has served to highlight the importance of diabetes as a risk factor, it has a number of problems. We propose that it would be more useful to consider diabetes as a myocardial infarction risk equivalent. This is not only more precise and in line with the literature but also conveys better the message that patients with diabetes and one or more previous myocardial infarction(s) are at even higher risk.

Effect of aspirin dose on mortality and cardiovascular events in people with diabetes: a meta-analysis

OBJECTIVES

Pharmacologic evidence suggests adequate antiplatelet activity in diabetic patients requires >100 mg aspirin daily, yet recent trials have used ≤100 mg daily. This meta-analysis explored the relationship between aspirin dose and prevention of cardiovascular events.

DATA SOURCES

Six electronic databases were searched using database-appropriate terms for aspirin, diabetes, and comparative study from inception until February 2010.

REVIEW METHODS

Randomized controlled trials and cohort studies comparing aspirin to no antiplatelet therapy were included if they reported cardiovascular events as pre-specified outcomes, aspirin dose, and number of diabetic patients. Studies were stratified by daily aspirin dose (≤100 mg; 101-325 mg; >325 mg) and pooled risk ratios (RR) were calculated using random effects models. All-cause mortality was the primary outcome of interest. Cardiovascular-related mortality, myocardial infarction, and stroke were secondary outcomes.

RESULTS

Data for diabetic patients were available from 21 studies (n = 17,522). Overall, 1,172 (15.4%) of 7,592 aspirin users and 1,520 (18.4%) of 8,269 controls died (p = 0.31). The pooled RRs were 0.89 (95% CI: 0.72-1.10; p = 0.27) from 13 studies using ≤100 mg (I(2) = 64%); 0.89 (95% CI: 0.61-1.30; p = 0.55) from four studies using 101-325 mg (I(2) = 83%); and 0.96 (95% CI: 0.85-1.08; p = 0.50) from eight studies using >325 mg (I(2) = 0%). Aspirin use was associated with a significantly lower risk of mortality (RR: 0.82; 95% CI: 0.69-0.98; p = 0.03) in 13 secondary prevention studies (I(2) = 27%), whereas aspirin use in seven primary prevention studies (I(2) = 0%) was not (RR: 1.01; 95% CI 0.85-1.19; p = 0.94). A substantial amount of heterogeneity was observed amongst studies in all outcomes. Although inclusion of cohort studies was a major source of heterogeneity, stratification by study design did not reveal a significant dose-response relationship.

CONCLUSIONS/INTERPRETATION

This summary of available data does not support an aspirin dose-response effect for prevention of cardiovascular events in diabetic patients. However, the systematic review identified an important gap in randomized controlled trial evidence for using 101-325 mg aspirin daily in diabetes.