Randomised trial of prophylactic daily aspirin in British male doctors

Development of a standardized definition for clinically significant bleeding in the ASPirin in Reducing Events in the Elderly (ASPREE) trial

Background

Bleeding is the major risk of aspirin treatment, especially in the elderly. A consensus definition for clinically significant bleeding (CSB) in aspirin primary prevention trials is lacking in the literature.

Methods

This paper details the development, modification, application, and quality control of a definition for clinically significant bleeding in the ASPirin in Reducing Events in the Elderly (ASPREE) trial, a primary prevention trial of aspirin in 19,114 community-dwelling elderly men and women. In ASPREE a confirmed bleeding event needed to meet criteria both for substantiated bleeding and clinical significance. Substantiated bleeding was defined as: 1) observed bleeding, 2) a reasonable report of symptoms of bleeding, 3) medical, nursing or paramedical report, or 4) imaging evidence. Bleeding was defined as clinically significant if it: 1) required transfusion of red blood cells, 2) required admission to the hospital for >24 h, or prolonged a hospitalization, with bleeding as the principal reason, 3) required surgery to stop the bleeding, or 4) resulted in death. Bleeding sites were subclassified as upper gastrointestinal, lower gastrointestinal, intracranial (hemorrhagic stroke, subarachnoid hemorrhage, subdural hematoma, extradural hematoma, or other), or other sites. Potential events were retrieved from medical records, self-report or notification from treating doctors. Two reviewers adjudicated each event using electronic adjudication software, and discordant cases were reviewed by a third reviewer. Adjudication rules evolved to become more strictly defined as the trial progressed and decision rules were added to assist with frequent scenarios such as post-operative bleeding.

Conclusions

This paper provides a detailed methodologic description of the development of a standardized definition for clinically significant bleeding and provides a benchmark for development of a consensus definition for future aspirin primary prevention trials.

Trial registration

ASPREE is registered on the International Standard Randomized Controlled Trial Number Register (ISRCTN83772183) and on clinicaltrials.gov (NCT01038583).

Application and impact of run-in studies

BACKGROUND

A run-in phase is often employed prior to randomization in a clinical trial to exclude non-adherent patients, placebo responders, active drug non-responders, or patients who do not tolerate the active drug. This may impact the generalizability of trial results.

OBJECTIVE

To determine if clinical outcomes differed between randomized controlled trials with run-in phases compared with randomized controlled trials of the same medication without run-in phases.

DESIGN, PARTICIPANTS

From 2006 to 2014, the Food and Drug Administration approved 258 new medications. Sitaglitpin, saxagliptin, linagliptin, and alogliptin were among the only drugs with a common mechanism of action that each had multiple clinical trials, some of which had run-in phases and some of which did not. We identified all published randomized controlled trials for these four medications from MEDLINE and EMBASE as well as prior systematic reviews.

MAIN MEASURES

We extracted key measures of medication efficacy (reduction in hemoglobin A1C) and safety (serious adverse events) from qualifying trials. Study results were pooled for each medication using random effects meta-analysis.

KEY RESULTS

We identified 106 qualifying trials for DPP4 inhibitors, of which 88 had run-in phases and 18 did not. The average run-in phase duration was 4.0 weeks (range 1-21), and 73% of run-in phases administered placebo rather than active drug. The reduction in hemoglobin A1C compared to baseline was similar for trials with and without run-in phases (0.70%, 95% confidence interval [CI] 0.65-0.75 vs 0.76%, 95% CI 0.69-0.84, p = 0.27). The proportion of patients with serious adverse events was also similar for trials with and without run-in phases (4%, 95% CI: 3-5% vs 3%, 95% CI: 1-4%, p = 0.35).

CONCLUSION

Trials with run-in phases provided similar estimates for medication efficacy and safety compared to trials without run-in phases. Because run-in phases are costly and time-consuming, these results call their utility into question for clinical trials of short duration.

Effects of daily aspirin on cancer incidence and mortality in the elderly Japanese

BACKGROUND

Long-term follow-up of studies to investigate preventive effects of aspirin on arterial thrombosis indicate that aspirin reduces the incidence and mortality of some cancers in Western populations.

OBJECTIVES

To explore the effects of aspirin on cancer incidence and mortality in the elderly Japanese.

PATIENTS/METHODS

Patients aged 60 to 85 years, presenting with hypertension, dyslipidemia, or diabetes mellitus (n = 14 601, 7297 in the aspirin group and 7304 in the no-aspirin group) participated the Japanese Primary Prevention Project (JPPP), a multicenter, open-label, randomized, parallel-group trial. A subanalysis of JPPP was performed to analyze the incidence of newly diagnosed cancer and death related to cancer.

RESULTS

The cumulative incidence of newly diagnosed cancer was 5.60% (4.65-6.64%) in the aspirin group and 4.14% (3.67-4.66%) in the no-aspirin group. The hazard ratio for newly diagnosed cancer was 1.24 (1.06-1.46), and the cancer incidence was significantly higher in the aspirin group. The cumulative cancer mortality was 1.96% (1.65-2.31%) in the aspirin group and 1.87% (1.56-2.22%) in the no-aspirin group, with no statistically significant difference. The Fine and Gray model suggested that the difference in the incidence of newly diagnosed cancer between the two groups decreased year by year.

CONCLUSIONS

Low-dose aspirin use did not reduce the cancer incidence or cancer mortality during a 5-year-average study period in the elderly Japanese. The cancer incidence in the aspirin group might decrease, however, to less than that in the no-aspirin group after the study period. Aspirin use might have led to earlier cancer diagnosis in our study.

Meta-analysis of aspirin use and risk of lung cancer shows notable results

Aspirin is a promising agent for chemoprevention of lung cancer. We assessed the association of aspirin use and the development of lung cancer, with a focus on heterogeneity between studies. Databases were searched for relevant studies until September 2014. Studies evaluating the relationship of aspirin use and incidence of lung cancer were considered. Relative risks (RR) were extracted and a pooled estimate was calculated. Heterogeneity was assessed by the I measure, random-effects models, and finite-mixture models. Sources of heterogeneity were investigated using a meta-regression. A decreased risk of lung cancer was found including 20 studies [RR=0.87, 95% confidence interval (CI): 0.79-0.95] on the basis of a random-effects model. Strong heterogeneity was observed (τ=0.0258, I=74.4%). As a result, two subpopulations of studies were identified on the basis of a mixture model. The first subpopulation (42%) has an average RR of 0.64. The remaining subpopulation (58%) shows an RR of 1.04. Different results were found for case-control (RR=0.74, 95% CI: 0.60-0.90) and cohort studies (RR=0.99, 95% CI: 0.93-1.06) in a stratified analysis. In a subgroup analysis, use of aspirin was associated with a decreased risk of non-small-cell lung cancer in case-control studies (RR=0.74; 95% CI: 0.58-0.94). At first glance, our meta-analysis shows an average protective effect. A second glance indicates that there is strong heterogeneity. This leads to a subpopulation with considerable benefit and another subpopulation with no benefit. For further investigations, it is important to identify populations that benefit from aspirin use.

Migraine with aura and persistent foramen ovale

The association between migraine with aura and persistent foramen ovale (PFO), as well as other right-to-left shunts, is described. A hypothesis that might explain this association is discussed. Observational studies suggested that when a PFO is closed patients who have migraine with aura are usually improved. The Migraine Intervention with STARFlex Technology (MIST) Trial was a randomised double-blind trial in patients with severe intractable migraine with aura and a moderate-large PFO that compared implantation of STARFlex devices with the intention of closing their PFO versus a sham procedure. It was hoped that the trial would demonstrate whether PFO closure would cure migraine. A series of problems in design and execution of the trial are discussed.

Antithrombotic effect and mechanism of Rubus spp. Blackberry

The compounds of Rubus spp. Blackberry (RSB) were isolated and identified by a bioassay-guided method, and their antithrombotic effects and mechanism were investigated with the acute blood stasis rat model. The RSB extract was evaluated by activated partial thromboplastin time (APTT), thrombin time (TT), prothrombin time (PT), and fibrinogen (FIB) assays in vitro. Results indicated that RSB extract exhibited anticoagulant activity. In addition to compounds 1 and 6, the other compounds also exhibited anticoagulant activity in vitro. Therefore, the in vivo antithrombosis effects of RSB extract were investigated by measuring whole blood viscosity (WBV), plasma viscosity (PV), APTT, PT, TT, and FIB. Meanwhile, the levels of thromboxane B2 (TXB₂), 6-keto prostaglandin F1α (6-keto-PGF1α), endothelial nitric oxide synthase (eNOS) and ET-1 (endothelin-1) were measured. Results suggested that RSB extract had inhibitory effects on thrombus formation, and its antithrombotic effects were associated with the regulation of vascular endothelium active substance, activation of blood flow and an anticoagulation effect.

Reduced platelet aggregation in women after intercourse: a possible role for the cyclooxygenase pathway

We hypothesise that molecules in the cyclooxygenase pathway affect platelet activity when seminal fluid (SF) is present. We considered the influence of SF on platelet aggregation in women, and believe that the prostanoids in SF signalling are significant. Thirty-one female subjects were studied, 20 of whom were sexually active. Male partners were given either aspirin or indomethacin to inhibit cyclooxygenase. The 6-keto prostaglandin F1α (6-keto PGF1α) and prostaglandin E metabolite (PGE-M) in SF were measured by competitive assay. Platelets and prostanoids were evaluated in women, periodically, before and after intercourse. The platelets were tested with adenosine diphosphate (ADP) and arachidonic acid (AA). To block the interaction between the uterus and SF, some couples used condoms. We found that the 6-keto prostaglandin F1α in urine at 2 hours post-intercourse (1418.75 pg/mL, Std 688.39) was greater than pre-intercourse (772.68 pg/mL, Std 116.54). Post-intercourse, a transient decrease in platelet aggregation was observed in women whose partners did not use condoms. Averages for platelet aggregation were 20.16% with ADP, and more significantly, 37.79% with AA after 2 hours. In contrast, couples using condoms showed no changes, averaging 64.02% with ADP and 72.06% with AA. Women whose partners were taking aspirin or indomethacin also showed no changes. SF from men taking aspirin or indomethacin led to no reduction in platelet aggregometry in their partners. These results indicate that in cases of exposure to SF, the transient change in women's platelet activity could be related to the cyclooxygenase pathway.

Aspirin for Primary Prevention

Aspirin reduces the risk of nonfatal myocardial infarction and stroke, and the risk of colorectal cancer. Aspirin increases the risk of gastrointestinal and intracranial bleeding. The best available evidence supports initiating aspirin in select populations. In 2016, the US Preventive Services Task Force recommended initiating aspirin for the primary prevention of both cardiovascular disease and colorectal cancer among adults ages 50 to 59 who are at increased risk for cardiovascular disease. Adults 60 to 69 who are at increased cardiovascular disease risk may also benefit. There remains considerable uncertainty about whether younger and older patients may benefit.

Epidemiology in diabetes mellitus and cardiovascular disease

As one of the leading causes of death in the USA, diabetes mellitus (DM) has become an epidemic over the past few decades. Despite the high prevalence of diagnosed DM, close to half of all people with DM are unaware of their disease. The risk of type 2 DM is determined by interplay of genetic and metabolic factors. Patients with type 2 DM have a higher risk of death from cardiovascular causes compared with their nondiabetic counterparts, and the mortality rate of DM associated cardiovascular disease is different among ethnicity groups and sex groups. Because of its adverse effect on people's health, DM also imposes an economic burden on individuals and households affected, as well as on the healthcare system. Current guidelines for cardiovascular disease prevention have focused on lifestyle management, blood pressure control, lipid control, blood glucose control, antiplatelet agent use, and tobacco use cessation.

The Dutch SCORE-based risk charts seriously underestimate the risk of cardiovascular disease

INTRODUCTION

Dutch cardiovascular disease (CVD) prevention guidelines recommend the use of modified SCORE risk charts to estimate 10-year risk of fatal and nonfatal CVD (myocardial infarction, cerebrovascular disease and congestive heart failure). This combined risk is derived from the SCORE mortality risk using multipliers. These multipliers have been shown to underestimate overall CVD risk. We aimed to compare the current Dutch risk charts with charts that estimate a broader range of clinically relevant CVD using updated multipliers.

METHODS

We constructed new risk charts for 10-year CVD using updated, recently published multipliers from the EPIC-Norfolk study, based on ratios of fatal CVD to clinically relevant CVD (fatal plus nonfatal CVD requiring hospitalisation for ischaemic heart disease, cardiac failure, cerebrovascular disease, peripheral artery disease, and aortic aneurysm). Our primary outcome was the proportion of the three risk categories, i. e. 'high risk' (>20% 10-year risk), 'intermediate risk' (10-19%) and 'low risk' (<10%) in the new risk charts as compared with the current risk charts.

RESULTS

Applying the updated fatal CVD/clinical CVD multipliers led to a marked increase in the high-risk categories (109 (27%) vs. 244 (61%), (p < 0.001)), an absolute increase of 229%. Similarly, the number of low-risk categories decreased (190 (48%) vs. 81 (20%) (p < 0.001)).

CONCLUSION

The current Dutch risk charts seriously underestimate the risk of clinical CVD, even in the first 10 years. Even when analyses are restricted to CVD events that required hospitalisation, true 10-year risks are more than double the currently estimated risks. Future guidelines may be revised to reflect these findings.

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The effectiveness of aspirin for migraine prophylaxis: a systematic review

CONTEXT AND OBJECTIVE:

Many researchers have suggested that aspirin prevents migraines. However, the evidence is unclear. The aim of this study was to analyze the available evidence on the effect of aspirin as a migraine prophylactic.

DESIGN AND SETTING:

Systematic review, conducted at the Pontifícia Universidade Católica do Paraná, Brazil, and at the University of São Paulo, Brazil.

METHODS:

We performed electronic searches in the databases of MEDLINE/PubMed, Embase, WEB OF SCIENCE, the World Health Organization, CENTRAL and OpenGrey, and we also searched manually for interventional studies published before April 2016 that compared the effects of aspirin with a control, in adults. Two authors independently extracted data on the publication, population recruited, intervention (aspirin dosage, follow-up and combined treatment) and main outcomes (frequency, severity and duration of migraine). We evaluated the quality of the studies using the Cochrane risk-of-bias tool.

RESULTS:

Our search retrieved 1,098 references, of which 8 met the selection criteria for this systematic review. The total population was 28,326 participants (18-64 years old); most (96%) were men. The dosage varied from 50 to 650 mg/day across the studies. The risk of bias was generally low or unclear. The only outcome for which most of the studies included (6/8) reported a significant reduction was frequency of migraine, which was reduced at an aspirin dosage of at least 325 mg/day.

CONCLUSION:

Aspirin can reduce the frequency of migraines. However, the optimal dosage is unclear.

Systematic review with meta-analysis: the comparative effectiveness of aspirin vs. screening for colorectal cancer prevention

BACKGROUND

Both aspirin use and screening with flexible sigmoidoscopy or guaiac faecal occult blood testing (FOBT) may reduce mortality from colorectal cancer, but comparative effectiveness of these interventions is unknown.

AIM

To compare aspirin to guaiac FOBT screening with regard to incidence and mortality of colorectal cancer in a network meta-analysis.

METHODS

We searched Medline, EMBASE and the COCHRANE central register (CENTRAL) for relevant randomised trials identified until 31 October 2015. Randomised trials in average-risk populations that reported colorectal cancer mortality, colorectal cancer incidence, or both, with a minimum follow-up of 2 years, and more than 100 randomised individuals were included. Three investigators independently extracted data. We calculated relative risks [RR with 95% predictive intervals (PrIs)] for the comparison of the interventions by frequentist network meta-analyses.

RESULTS

The effect of aspirin on colorectal cancer mortality was similar to FOBT (RR 1.03; 95% PrI 0.76-1.39) and flexible sigmoidoscopy (RR 1.16; 95% PrI 0.84-1.60). Aspirin was more effective than FOBT (RR 0.36; 95% PrI 0.22-0.59) and flexible sigmoidoscopy (RR 0.37; 95% PrI 0.22-0.62) in preventing death from or cancer in the proximal colon. Aspirin was equally effective as screening in reducing colorectal cancer incidence, while flexible sigmoidoscopy was superior to FOBT (RR 0.84; 95% PrI 0.72-0.97).

CONCLUSIONS

Low-dose aspirin seems to be equally effective as flexible sigmoidoscopy or guaiac FOBT screening to reduce colorectal cancer incidence and mortality, and more effective for cancers in the proximal colon. A randomised comparative effectiveness trial of aspirin vs. screening is warranted.

The Benefit and Safety of Aspirin for Primary Prevention of Ischemic Stroke: A Meta-Analysis of Randomized Trials

Background: Although aspirin is effective in the secondary prevention of stroke among men and women, its use in primary prevention remains controversial. We conducted a meta-analysis of randomized trials to evaluate the benefit and safety of aspirin for the primary prevention of ischemic stroke. Methods: We searched three electronic databases (Medline, the Cochrane Central Register of Controlled Trials, and Embase) for articles published before August 1st, 2016. Randomized trials reporting the effect of aspirin on the primary prevention of ischemic stroke and its side effects (hemorrhagic stroke and severe gastrointestinal bleeding) were included. We used a fixed-effect model to quantify the effect of aspirin on the primary prevention of stroke when the heterogeneity was low, or else applied the random-effect model. Results: Fourteen randomized trials were included. Overall, aspirin use was associated with a decreased risk of ischemic stroke compared with non-aspirin use (OR: 0.83, 95% CI: 0.74-0.93, P = 0.45). In subgroup analyses, the effect of aspirin on ischemic stroke in apparently healthy adults remained significant (OR: 0.83, 95% confidence interval: 0.74-0.94, I² = 22%, P = 0.28); while in patients with cardiovascular diseases there was no difference in the risk of ischemic stroke between aspirin and non-aspirin groups (OR: 0.75, 95% confidence interval: 0.44-1.29, P = 0.46). As for adverse effects, the prophylactic use of aspirin potentially increased the risk of serious bleeding events in a population of apparently healthy individuals and in patients with previous cardiovascular diseases. Conclusion: This meta-analysis of randomized trials indicated that both the apparently healthy adults and patients with cardiovascular diseases will derive little protective benefit from aspirin considering the increased risk of severe bleeding events.

Systematic Review and Meta-Analysis of Randomised Trials to Ascertain Fatal Gastrointestinal Bleeding Events Attributable to Preventive Low-Dose Aspirin: No Evidence of Increased Risk

BACKGROUND

Aspirin has been shown to lower the incidence and the mortality of vascular disease and cancer but its wider adoption appears to be seriously impeded by concerns about gastrointestinal (GI) bleeding. Unlike heart attacks, stroke and cancer, GI bleeding is an acute event, usually followed by complete recovery. We propose therefore that a more appropriate evaluation of the risk-benefit balance would be based on fatal adverse events, rather than on the incidence of bleeding. We therefore present a literature search and meta-analysis to ascertain fatal events attributable to low-dose aspirin.

METHODS

In a systematic literature review we identified reports of randomised controlled trials of aspirin in which both total GI bleeding events and bleeds that led to death had been reported. Principal investigators of studies in which fatal events had not been adequately described were contacted via email and asked for further details. A meta-analyses was then performed to estimate the risk of fatal gastrointestinal bleeding attributable to low-dose aspirin.

RESULTS

Eleven randomised trials were identified in the literature search. In these the relative risk (RR) of 'major' incident GI bleeding in subjects who had been randomised to low-dose aspirin was 1.55 (95% CI 1.33, 1.83), and the risk of a bleed attributable to aspirin being fatal was 0.45 (95% CI 0.25, 0.80). In all the subjects randomised to aspirin, compared with those randomised not to receive aspirin, there was no significant increase in the risk of a fatal bleed (RR 0.77; 95% CI 0.41, 1.43).

CONCLUSIONS

The majority of the adverse events caused by aspirin are GI bleeds, and there appears to be no valid evidence that the overall frequency of fatal GI bleeds is increased by aspirin. The substantive risk for prophylactic aspirin is therefore cerebral haemorrhage which can be fatal or severely disabling, with an estimated risk of one death and one disabling stroke for every 1,000 people taking aspirin for ten years. These adverse effects of aspirin should be weighed against the reductions in vascular disease and cancer.

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 Use for the Primary Prevention of Cardiovascular Disease in the Elderly

OBJECTIVE

This article aims to use the available evidence assessing aspirin for primary prevention of cardiovascular (CV) events in the elderly to determine its appropriate use.

DATA SOURCES

A literature search of clinical trials and meta-analyses was conducted using MEDLINE and PubMed with the search terms aspirin, bleeding, CV events, elderly, geriatrics, hemorrhage, myocardial infarction (MI), primary prevention, and stroke.

STUDY SELECTION/DATA EXTRACTION

Twelve hundred fourteen (1,214) articles were initially found, and 55 were reviewed. These articles assessed the use of aspirin for primary prevention of CV events. Only trials comparing aspirin with placebo, a non-antiplatelet, or a non-anticoagulant were included in this review. Of the articles reviewed, 10 met the stated criteria.

DATA SYNTHESIS

It is well documented that the risk of CV events increases as patients age. Primary prevention of these events with aspirin may be beneficial in some patients. Currently, a specific recommendation for the use of aspirin for primary prevention in the geriatric population is not available. This paper reviews the available evidence for primary prevention of CV disease. This population is under-represented in the literature, making it challenging to apply the study findings.

CONCLUSION

Aspirin may be considered for the primary prevention of CV events in the elderly population. Because of the lack of data in patients 80 years of age and older, it is difficult to make a decision on the initiation of aspirin therapy in this population. Additional research is necessary to better balance the risk versus benefit of this treatment option.

Randomized controlled trials: who fails run-in?

BACKGROUND

Early identification of participants at risk of run-in failure (RIF) may present opportunities to improve trial efficiency and generalizability.

METHODS

We conducted a partial factorial-design, randomized, controlled trial of calcium and vitamin D to prevent colorectal adenoma recurrence at 11 centers in the United States. At baseline, participants completed two self-administered questionnaires (SAQs) and a questionnaire administered by staff. Participants in the full factorial randomization (calcium, vitamin D, both, or neither) received a placebo during a 3-month single-blinded run-in; women electing to take calcium enrolled in a two-group randomization (calcium with vitamin D, or calcium alone) and received calcium during the run-in. Using logistic regression models, we examined baseline factors associated with RIF in three subgroups: men (N = 1606) and women (N = 301) in the full factorial randomization and women in the two-group randomization (N = 666).

RESULTS

Overall, 314/2573 (12 %) participants failed run-in; 211 (67 %) took fewer than 80 % of their tablets (poor adherence), and 103 (33 %) withdrew or were uncooperative. In multivariable models, 8- to 13-fold variation was seen by study center in odds of RIF risk in the two largest groups. In men, RIF decreased with age (adjusted odds ratio [OR] per 5 years 0.85 [95 % confidence interval, CI; 0.76-0.96]) and was associated with being single (OR 1.65 [95 % CI; 1.10-2.47]), not graduating from high school (OR 2.77 [95 % CI; 1.58-4.85]), and missing SAQ data (OR 1.97 [1.40-2.76]). Among women, RIF was associated primarily with health-related factors; RIF risk was lower with higher physical health score (OR 0.73 [95 % CI; 0.62-0.86]) and baseline multivitamin use (OR 0.44 [95 % CI; 0.26-0.75]). Women in the 5-year colonoscopy surveillance interval were at greater risk of RIF than those with 3-year follow-up (OR 1.91 [95 % CI; 1.08-3.37]), and the number of prescription medicines taken was also positively correlated with RIF (p = 0.03). Perceived toxicities during run-in were associated with 12- to 29-fold significantly increased odds of RIF.

CONCLUSIONS

There were few common baseline predictors of run-in failure in the three randomization groups. However, heterogeneity in run-in failure associated with study center, and missing SAQ data reflect potential opportunities for intervention to improve trial efficiency and retention.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00153816 . Registered September 2005.

Aspirin dosing in cardiovascular disease prevention and management: an update

Aspirin has been in use for prevention and management of cardiovascular diseases for several decades. Clinical and epidemiological literature suggests that while net benefits of aspirin in primary prevention of CVDs are less clear, the benefits of aspirin in acute scenarios and secondary prevention settings are well established. However, its optimum dosing requirements have been up for debate especially in various settings of acute coronary syndrome and stable ischemic heart disease. The role of clinician in stratifying individual risk score to achieve net clinical benefit is an important determinant of initiating aspirin therapy. The purpose of this article is to review association of aspirin and CVD in general, and to review its dosing regimens in acute settings as well as primary and secondary prevention as suggested by various established guidelines. We also aim to provide the readers an update on recent changes and current evidence based practice trends.

Citric Acid Enhances the Antithrombotic Effect of Aspirin in Many Aspirin-Resistant Subjects

This study had three objectives: (1) to determine the frequency of high platelet aggregators in a consecutive series of 268 apparently healthy volunteers who presented to our Center; (2) to assess the inhibitory effect of aspirin (ASA) on these high aggregators; (3) to determine, in a double-blind trial, whether or not the addition of citric acid (CTA) to ASA would increase its inhibitory effect in subjects who had a suboptimal response to aspirin alone. A platelet aggregation-scoring methodology developed for turbidimetric platelet aggregometry was used to quantify baseline aggregation and medicinal effects. We define a high aggregator as one whose unmedicated PA score is ≥30. We define the response of a high aggregator to ASA as poor if the medicated PA score stays at ≥30. We found that 58 of 268 apparently healthy unmedicated volunteers (22%) had PA scores ≥30. and that 27 of these (47%) had a poor response to 325 mg ASA, with an average drop in their PA scores from 49.5 ± 13.1 to 41.1 ± 8.6 (16%). Twenty-five of these 27 people were enrolled in the double-Mind study comparing the effect of ASA and ASA + CTA on platelet aggregability. Of these high aggregators who had a poor response to ASA, 12 of 25 (50%) had a good response to 162.5 mg of ASA plus 162.5 mg of CTA, with an average drop of their PA scores from 46.7 ± 13.2 to 22.0 ± 5.2 (53%). CTA alone had no effect on the PA score, which was similar to the control placebo. Our data suggest that a 1:1 combination of ASA and CTA may offer significantly greater protection agairtst arterial thrombotic events than ASA alone in subjects who respond poorly to ASA. Key Words: Platelet aggregation—Antithrombotic medication—Thrombosis.

Platelets as Predictors of Vascular Risk: Is There a Practical Index of Platelet Activity?

Activated platelets play a role in the pathogenesis of coronary heart disease (CHD). Following activation, platelets change shape, aggregate, and release several bioactive substances. The aim of this review is to identify if there is a simple and cost-effective method that indicates platelet activation and predicts the risk of CHD and vascular events. The rationale for identifying high-risk patients is to reduce their risk of vascular events by administering appropriate and effective antiplatelet treatment, like aspirin, clopidogrel, or combination regimens. Many laboratory tests estimating platelet activity have been described. Some are relatively simple, such as spontaneous or agonist-induced platelet aggregation. Other tests include measuring the mean platelet volume (MPV) or plasma soluble P-selectin levels. Some more complex tests include flow cytometry to determine platelet GP Ilb/Illa receptors, platelet surface P-selectin, plateletmonocyte aggregates, and microparticles. Only few prospective studies assessed the predictive value of platelet activation in healthy individuals. Although the MPV seems an 'easy method, there are insufficient data supporting its ability to predict the risk of a vascular event in healthy adults. Platelet aggregation, in whole blood or in platelet-rich plasma was not consistently predictive of vascular risk. Soluble P-selectin measurement is a promising method but it needs further evaluation. Flow cytometry methods are costly, time-consuming, and need specialized equipment. Thus, they are unlikely to be useful in estimating the risk in large numbers of patients. There is as yet no ideal test for the detection of platelet activation. Each currently available test has merits and disadvantages. Simple methods such as the MPV and the determination of platelet release products need further evaluation.

Primary Prevention of Coronary Heart Disease in the Elderly

OBJECTIVE:

To review relevant literature supporting the use of antihypertensive agents, lipid-lowering agents (i.e., statins), and aspirin therapy for the primary prevention of coronary heart disease (CHD) in an elderly patient population (age ≥65 y).

DATA SOURCES:

A MEDLINE search (1988–January 2003) was conducted.

STUDY SELECTION AND DATA EXTRACTION:

Primary and tertiary literature involving the uses of antihypertensives, statins, and aspirin therapy in the elderly were reviewed.

DATA SYNTHESIS:

Mortality due to CHD in the US population has decreased 40–50% over the last 30 years; however, CHD remains the leading cause of morbidity and mortality in elderly persons. As the population continues to age, the number of older adults eligible for primary prevention will rise. The American Heart Association clinical practice guidelines for the primary prevention of CHD were updated in 2002; however, they are based on findings from clinical trials that enrolled predominantly middle-aged white men. The recommendations for elderly individuals are predominantly extrapolated from subgroup analyses of randomized clinical trials or cohort studies. This literature suggests that elderly persons are candidates for primary prevention measures and experience reductions in coronary events when treated with appropriate therapies.

CONCLUSIONS:

Data suggest that use of antihypertensives, statins, and aspirin therapy in the elderly appears effective to an extent similar to, and often greater than, that observed in younger patients. We believe these agents should be prescribed to all appropriate high-risk elderly patients. Ongoing and future studies will more clearly elucidate the benefits of primary prevention therapy, particularly in persons ≥75 years of age.

Platelets and Cardiovascular Disease

Platelets play an important, but often under-recognized role in cardiovascular disease. For example, the normal response of the platelet can be altered, either by increased pro-aggregatory stimuli or by diminished anti-aggregatory substances to produce conditions of increased platelet activation/aggregation and occur in active cardiovascular disease states both on a chronic (e.g. stable angina pectoris) and acute basis (e.g. acute myocardial infarction). In addition, platelet hyperaggregability is also associated with the risk factors for coronary artery disease (e.g. smoking, hypertension, and hypercholesterolaemia). Finally, the utility of an increasing range of anti-platelet therapies in the management of the above disease states further emphasizes the pivotal role platelets play in the pathogenesis of cardiovascular disease. This paper provides a comprehensive overview of the normal physiologic role of platelets in maintain homeostasis, the pathophysiologic processes that contribute to platelet dysfunction in cardiovascular disease and the associated role and benefits of anti-platelet therapies.

Cost-effective recruitment methods for a large randomised trial in people with diabetes: A Study of Cardiovascular Events iN Diabetes (ASCEND)

Background

Clinical trials require cost-effective methods for identifying, randomising, and following large numbers of people in order to generate reliable evidence. ASCEND (A Study of Cardiovascular Events iN Diabetes) is a randomised ‘2 × 2 factorial design’ study of aspirin and omega-3 fatty acid supplements for the primary prevention of cardiovascular events in people with diabetes; this study used central disease registers and a mail-based approach to identify, randomise, and follow 15,000 people. In collaboration with UK consultants and general practitioners (GPs), researchers identified potentially eligible people with diabetes from centrally held registers (e.g. for retinopathy screening) and GP-held disease registers. Permission was obtained under section 251 of the National Health Service Act 2006 (previously section 60 of the NHS act 2001) to allow invitation letters to be generated centrally in the name of the holder of the register. In addition, with the collaboration of the National Institutes for Health Research (NIHR) Diabetes and Primary Care Research Networks (DRN and PCRN), general practices sent pre-assembled invitation packs to people with a diagnosis of diabetes. Invitation packs included a cover letter, screening questionnaire (with consent form), information leaflet, and a Freepost envelope. Eligible patients entered a 2-month, pre-randomisation, run-in phase on placebo tablets and were only randomised if they completed a randomisation form and remained willing and eligible at the end of the run-in. Follow-up is ongoing, using mail-based approaches that are being supplemented by central registry data.

Results

Information on approximately 600,000 people listed on 58 centrally held diabetes registers was obtained, and 300,188 potentially eligible patients were invited to join the study. In addition, 785 GP practices mailed invitations to 120,875 patients. A further 2,340 potential study participants were identified via other routes. In total, 423,403 people with diabetes were invited to take part; 26,462 entered the 2-month, pre-randomisation, run-in phase; and 15,480 were randomised.

Conclusion

If sufficient numbers of potentially eligible patients can be identified centrally and the trial treatments do not require participants to attend clinics, the recruitment and follow-up of patients by mail is feasible and cost-effective. Wider use of these methods could allow more, large, randomised trials to be undertaken successfully and cost-effectively.

Trial registration

Current Controlled Trials, ISRCTN60635500, registered on 14 July 2005

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1354-9) contains supplementary material, which is available to authorized users.

Which Aspirin Dose and Preparation Is Best for the Long-Term Prevention of Cardiovascular Disease and Cancer? Evidence From a Systematic Review and Network Meta-Analysis

The evidence base on aspirin in primary prevention suggests that it can reduce significantly the risk of cardiovascular disease (CVD) events and cancer, especially colorectal, albeit increasing bleeding. There is, however, uncertainty on the optimal aspirin dose and preparation for primary prevention. We thus aimed to review main sources of evidence informing on daily dosage and preparation of aspirin for primary prevention of CVD and cancer. We collected and elaborated aspirin effectiveness and safety data from U.S. Preventive Services Task Force reports on aspirin in primary prevention, distinguishing average daily dose in <100mg, 100mg, and >100mg. The following preparations were also systematically compared: enteric coated, controlled release, non-coated, or otherwise unspecified. Fixed-effect pairwise and network meta-analytic models were run in a frequentist framework. Eleven randomized trials were shortlisted, enrolling 104,101 subjects, followed for a median of 60months. At pairwise analysis, aspirin was associated with significant reductions in death and CVD events, non-significant reductions in cancer death or incidence, and significant increases in the risk of intracranial and gastrointestinal (GI) bleeding. An average daily dose of 100mg had the highest probability of reducing death, cancer death, and cancer incidence, whereas higher doses seemed superior for reducing CVD events, and 100mg or less daily proved better tolerated. Coated preparations appeared more beneficial for death, cancer death, cancer incidence, and GI bleeding, whereas controlled release preparations appeared better for CVD events and non-coated ones for intracranial bleeding. In conclusion, an average daily dose of 100mg of coated aspirin seems more likely to confer favorable preventive effects on death and cancer, with higher doses more appealing for CVD prevention and lower doses better tolerated.

Percutaneous closure of patent foramen ovale in migraine with aura, a randomized controlled trial

AIMS

Migraine with aura and patent foramen ovale (PFO) are associated. The Percutaneous Closure of PFO in Migraine with Aura (PRIMA) trial is a multicentre, randomized trial to investigate the effect of percutaneous PFO closure in patients refractory to medical treatment.

METHODS

Migraine with aura patients and PFO who were unresponsive to preventive medications were randomized to PFO closure or medical treatment. Both groups were given acetylsalicylic acid 75-100 mg/day for 6 months and clopidogrel 75 mg/day for 3 months. The primary endpoint was reduction in monthly migraine days during months 9-12 after randomization compared with a 3-month baseline phase before randomization. The committee reviewing the headache diaries were blinded to treatment assignment.

RESULTS

One hundred and seven patients were randomly allocated to treatment with an Amplatzer PFO Occluder (N = 53) or control with medical management (N = 54). The trial was terminated prematurely because of slow enrolment. Eighty-three patients (40 occluder, 43 control) completed 12-month follow-up. Mean migraine days at baseline were 8 (±4.7 SD) in the closure group and 8.3 (±2.4) in controls. The primary endpoint was negative with -2.9 days after PFO closure vs. -1.7 days in control group (P = 0.17). Patent foramen ovale closure caused five adverse events without permanent sequelae.

CONCLUSION

In patients with refractory migraine with aura and PFO, PFO closure did not reduce overall monthly migraine days.

A long-term risk-benefit analysis of low-dose aspirin in primary prevention

BACKGROUND

The long-term risk-benefit effect of occasional and regular use of low-dose aspirin (≤ 100 mg per day) in primary prevention of vascular diseases and cancers was calculated.

METHODS

One representative database of 1 000 000 participants from Taiwan's National Health Insurance scheme in 1997-2000 was used. The potential study subjects were those aged 30-95 years, were found not to have been prescribed aspirin before 1 January 2000, but to have first been prescribed low-dose aspirin (≤ 100 mg per day) after that date and were followed up to 31 December 2009. Participants prescribed low-dose aspirin < 20% during the study period were considered occasional users and those prescribed ≥ 80% regular users. After the propensity score matching, rate differences of haemorrhage, ischaemia and cancer between these users were calculated their net clinical risk.

RESULTS

A total of 1720 pairs were analysed. During the study period, haemorrhage and ischaemia occurred in 25 (1·45%) and 67 participants (3·90%) in occasional users and 69 (4·01%) and 100 participants (5·81%) in regular users, whereas cancer occurred in 32 participants (1·86%) in occasional users and 26 participants (1·51%) in regular users. The crude and adjusted net clinical risks of low-dose aspirin use between the two frequency of users (≥ 80% vs. < 20%) were 4·12% (95% CI = 2·19%, 6·07%; P < 0·001) and 3·93% (95% CI = 2·01%, 5·84%; P < 0·001).

CONCLUSIONS

A long-term regular use of low-dose aspirin might not be better than occasional use in the primary prevention against major vascular diseases and cancer.

Preventing cardiovascular disease in patients with diabetes: use of aspirin for primary prevention

Diabetics are at high risk for atherosclerotic cardiovascular disease (ASCVD) and are considered a coronary heart disease risk equivalent. The utility of aspirin in primary prevention of ASCVD in diabetic patients has been widely studied and is still debated. Overall, the current evidence suggests a modest benefit for reduction in ASCVD events with the greatest benefit among those with higher baseline risk, but at the cost of increased risk of gastrointestinal bleeding. Diabetic patients at higher risk (with 10-year ASCVD risk >10 %) are generally recommended for aspirin therapy if bleeding risk is felt to be low. A patient-provider discussion is recommended before prescribing aspirin therapy. Novel markers such as coronary artery calcium scores and high-sensitivity C-reactive protein may help refine ASCVD risk prediction and guide utility for aspirin therapy. This article will review the literature for the most up-to-date studies evaluating aspirin therapy for primary prevention of ASCVD in patients with diabetes.

Update on Prevention of Cardiovascular Disease in Adults With Type 2 Diabetes Mellitus in Light of Recent Evidence: A Scientific Statement From the American Heart Association and the American Diabetes Association

Cardiovascular disease risk factor control as primary prevention in patients with type 2 diabetes mellitus has changed substantially in the past few years. The purpose of this scientific statement is to review the current literature and key clinical trials pertaining to blood pressure and blood glucose control, cholesterol management, aspirin therapy, and lifestyle modification. We present a synthesis of the recent literature, new guidelines, and clinical targets, including screening for kidney and subclinical cardiovascular disease for the contemporary management of patients with type 2 diabetes mellitus.

Update on Prevention of Cardiovascular Disease in Adults With Type 2 Diabetes Mellitus in Light of Recent Evidence: A Scientific Statement From the American Heart Association and the American Diabetes Association

Cardiovascular disease risk factor control as primary prevention in patients with type 2 diabetes mellitus has changed substantially in the past few years. The purpose of this scientific statement is to review the current literature and key clinical trials pertaining to blood pressure and blood glucose control, cholesterol management, aspirin therapy, and lifestyle modification. We present a synthesis of the recent literature, new guidelines, and clinical targets, including screening for kidney and subclinical cardiovascular disease for the contemporary management of patients with type 2 diabetes mellitus.

Estimated 10-year cardiovascular mortality seriously underestimates overall cardiovascular risk

OBJECTIVE

The European Society of Cardiology's prevention guideline suggests that the risk of total (fatal plus non-fatal) cardiovascular disease (CVD) may be calculated from the risk of CVD mortality using a fixed multiplier (3×). However, the proposed multiplier has not been validated. We investigated the ratio of total CVD to CVD mortality in a large population-based cohort.

METHODS

CVD mortality and total CVD (fatal plus non-fatal CVD requiring hospitalisation) were analysed using Kaplan-Meier estimates among 24 014 men and women aged 39-79 years without baseline CVD or diabetes mellitus in the prospective population-based European Prospective Investigation of Cancer and Nutrition-Norfolk cohort. CVD outcomes included death and hospitalisations for ischaemic heart disease, heart failure, cerebrovascular disease, peripheral artery disease or aortic aneurysm. The main study outcome was the ratio of 10-year total CVD to 10-year CVD mortality stratified by age and sex.

RESULTS

Ten year CVD mortality was 3.9% (900 CVD deaths, 95% CI 3.6% to 4.1%); the rate of total CVD outcomes was 21.2% (4978 fatal or non-fatal CVD outcomes, 95% CI 20.7% to 21.8%). The overall ratio of total CVD to CVD mortality was 5.4. However, we found major differences in this ratio when stratified by gender and age. In young women (39-50 years), the ratio of total CVD to CVD mortality was 28.5, in young men (39-50 years) 11.7. In the oldest age group, these ratios were considerably lower (3.2 in women and 2.4 in men aged 75-79 years).

CONCLUSIONS

The relationship between 10-year total CVD and CVD mortality is dependent on age and sex, and cannot be estimated using a fixed multiplier. Using CVD mortality to estimate total CVD risk leads to serious underestimation of risk, particularly in younger age groups, and particularly in women.

Antiplatelet therapy as a modulator of stroke aetiology: a meta-analysis

AIMS

Antiplatelet therapy reduces the incidence of ischaemic stroke. Platelet-mediated thrombosis contributes variably to the major subtypes of stroke as defined by the TOAST criteria: large artery atherosclerosis (LAA), cardioembolic (CE) and small vessel occlusion (SVO). The effect of antiplatelet therapy on the incidence of each subtype is unknown and is the subject of this meta-analysis.

METHODS

Electronic databases were searched for articles comparing the effect of antiplatelet therapy on the incidence of stroke according to aetiological subtype. Studies containing subjects prescribed anticoagulant therapy or solely investigating subjects with atrial fibrillation were excluded. Pooled odds ratios (ORs) were calculated using a fixed effects model.

RESULTS

Nine studies were included (n = 5739). In patients who had an ischaemic stroke, pre-event antiplatelet therapy was associated with significantly decreased incidence of LAA (OR 0.88, 95% CI 0.79, 0.99; P = 0.026), increased incidence of CE (OR 1.23, 95% CI 1.08, 1.41; P = 0.002) and no effect on SVO (OR 0.99, 95% CI 0.88, 1.11; P = 0.806). Concordant non-significant trends were observed in primary prevention populations (n = 751): LAA (OR 0.81, 95% CI 0.57, 1.15; P = 0.240), CE (OR 1.29, 95% CI 0.89, 1.87; P = 0.179) and SVO (OR 0.99, 95% CI 0.73, 1.36; P = 0.970). Subgroup analysis of aspirin monotherapy (n = 3786) demonstrated a significant reduction in LAA (OR 0.87, 95% CI 0.76, 1.00; P = 0.046), but non-significant effects on the incidence of CE (OR 1.17, 95% CI 0.99, 1.39; P = 0.068) and SVO (OR 1.04, 95% CI 0.91, 1.20; P = 0.570). Probability of publication bias was low (P > 0.05).

CONCLUSIONS

Antiplatelet therapy preferentially reduces the incidence of LAA stroke compared with CE and SVO subtypes.

High-risk type-2 diabetes mellitus patients, without prior ischemic events, have normal blood platelet functionality profiles: a cross-sectional study

Background

Patients with type 2 diabetes mellitus (DM) display a predisposition for vascular disease. Platelets taken from vasculopathic diabetic patients, show enhanced stimuli-induced activation and aggregation responses. Aspirin remains the cornerstone antiplatelet agent for secondary prevention of vascular complications among diabetic patients, yet evidence of its efficacy and safety in primary prevention are conflicting. Our aim was to assess whether high risk diabetic patients, without previous ischemic events, have abnormal platelet functionality profiles.

Methods

The study included 82 diabetic patients and 86 matched non-diabetic patients without prior ischemic events nor treatment with anti-platelet medications. Blood samples were analyzed for platelet markers of activation, turnover and leukocyte-platelet interactions.

Results

Our final analysis included 122 males (74 %), with a mean age of 61 years. Mean platelet volume (MPV) was similar between the diabetic patients and controls (9.2 fL for both). Following activation, PAC-1 binding and P-selectin expression were found comparable between the diabetic patients and controls (83 % versus 81 % and 76 % versus 74 %, respectively). Leukocyte-platelet aggregates (LPAs) were similar between the diabetic patients and controls (18 % versus 17 %, respectively). Neutrophil-platelet aggregates (NPAs) and monocyte-platelet aggregates (MPAs) were also found similar in the diabetic patients and controls. Elevated fasting plasma glucose was associated with increased LPAs rates.

Conclusions

High risk type-2 diabetes mellitus patients, without prior ischemic events, have normal blood platelet functionality profiles.

Statins and aspirin: do they really work in women?

Cardiovascular disease continues to be the most common cause of mortality in women in the USA. As a result, greater emphasis has been placed on preventive measures. Studies examining the role of aspirin and HMG-CoA reductase inhibitors (statins) have shown important clinical differences in men versus women in the preventive realm. This has led to inconsistent recommendations by guideline committees and clinicians alike. This review presents a summary of the past and current guidelines. In addition, important clinical trials influencing current era practice are also discussed. Both strengths and limitations of these studies are described in detail, along with recommendations regarding future directions and the scope of aspirin and statin use for primary and secondary prevention of cardiovascular disease.

How to Understand Patent Foramen Ovale Clinical Significance - Part II: Therapeutic Strategies in Cryptogenic Stroke

In the first part of this review, we reminded that patent foramen ovale (PFO) is a slit or tunnel-like passage in the interatrial septum occurring in approximately 25% of the population and that a number of conditions have been linked to its presence, the most important being cryptogenic stroke (CS) and migraine. We have also shown how, in the setting of neurological events, it is not often clear whether the PFO is pathogenically-related to the index event or an incidental finding, and therefore we thought to provide some useful key points for understanding PFO clinical significance in a case by case evaluation. The controversy about PFO pathogenicity has consequently prompted a paradigm shift of research interest from medical therapy with antiplatelets or anticoagulants to percutaneous transcatheter closure, in secondary prevention. Observational data and meta-analysis of observational studies previously suggested that PFO closure with a device was a safe procedure with a low recurrence rate of stroke, as compared to medical therapy. However, so far, published randomized controlled trials (CLOSURE I^®, RESPECT^® and PC Trial^®) have not shown the superiority of PFO closure over medical therapy. Thus, the optimal strategy for secondary prevention of paradoxical embolism in patients with a PFO remains unclear. Moreover, the latest guidelines for the prevention on stroke restricted indications for PFO closure to patients with deep vein thrombosis and high-risk of its recurrence. Given these recent data, in the second part of the present review, we aim to discuss today treatment options in patients with PFO and CS, providing an updating on patients’ management.

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.

"Migraine side effect" and stroke recurrence in late follow-up after transcatheter patent foramen ovale closure as secondary prevention of cryptogenic thromboembolism

INTRODUCTION

Patent foramen ovale (PFO) is associated with cryptogenic strokes, recurrent transient neurologic deficits, sleep apnea, decompression illness and migraines with aura.

AIM

We verify cryptogenic embolism recurrence after transcatheter PFO closure in patients younger than 55 years old, and determine the prevalence of migraine with aura before and after PFO closure.

MATERIAL AND METHODS

We sent a questionnaire concerning the recurrence of stroke or transient ischemic attack (TIA) and the presence of migraine symptoms before and after PFO closure to 224 consecutive patients (mean age 40.9 ±9 years; 103 men; 108 patients < 40 years old, 116 patients 40-55 years old) after successful PFO transcatheter closure as secondary prevention of cryptogenic embolism.

RESULTS

The mean follow-up period was 37.8 ±32.5 (median 27) months. Stroke or TIA recurred in 6 patients (2.6%), all of whom were over 40 years old at the time of closure. The median time of recurrence was 24 months. Two patients (0.89%) died, but the deaths were not related to the device nor to thromboembolism. Migraine occurred in the study group before closure in 68 (30.4%) patients. After the procedure 55 (80.9%) reported improvement or disappearance of migraine symptoms.

CONCLUSIONS

Recurrent strokes after PFO closure are rare, and they occur more often in patients over 40 years old at the time of closure. The PFO closure results in migraine subsiding or symptoms noticeably ameliorating.