Low-dose Aspirin In Primary Prevention Research Articles

Evaluating Aspirin’s Efficacy for Primary Prevention in Cardiovascular and Cerebrovascular Disease: Insights from a Nationwide Cohort Study

The effectiveness of aspirin for the primary prevention of cerebro-cardiovascular diseases in Koreans remains unclear. Therefore, we evaluated the preventive effects of low-dose aspirin (equal or less than 100 mg) on cerebro-cardiovascular events. We conducted a retrospective cohort study using the National Sample Cohort dataset. From the 1,106,580 individuals eligible in 2004, we selected 200 individuals (47% male and 22.5% aged 65 or older) who consistently received low-dose aspirin from 2004 to 2013 for inclusion in the aspirin cohort. Participants for the control cohort, who did not use aspirin, were selected through propensity score matching based on variables. We compared the incidences of endpoints (acute myocardial infarction, cerebral infarction, gastrointestinal hemorrhage, and cerebral hemorrhage) between the aspirin group and the non-aspirin group over the 9-year follow-up period. There was no significant difference in the incidence rates of acute myocardial infarction, cerebral infarction, gastrointestinal hemorrhage, or cerebral hemorrhage between the aspirin and non-aspirin groups. Low-dose aspirin for primary prevention in Koreans did not reduce myocardial or cerebral infarctions and did not increase the risk of gastrointestinal or cerebral hemorrhage. Therefore, we suggest that aspirin for primary prevention should be used cautiously and tailored to the individual’s baseline cardiovascular risk.

Pharmacist-Led Deprescribing of Aspirin in Older People in an Outpatient Setting.

Background In 2019, the American College of Cardiology and American Heart Association updated their joint guidelines stating low-dose aspirin should not be used on a routine basis for primary prevention of atherosclerotic cardiovascular disease (ASCVD) among people older than 70 years of age because of increased bleeding risk.1 In addition to these updated guidelines, a statement released by the US Preventive Services Task Force in April 2022 recommends against the initiation of low-dose aspirin for primary prevention of cardiovascular disease in people 60 years of age or older.² Despite these updated recommendations, aspirin continues to be a common medication older patients take, providing an opportunity for a clinical pharmacist deprescribing intervention. Objective To identify the role of a pharmacist-led aspirin deprescribing intervention within a safety-net health system in the outpatient setting. Methods This project included patients 70 years of age and older who had aspirin listed as an active medication without documented ASCVD. This project assessed aspirin deprescribing rates, time spent on pharmacist outreach, and reasons for patient and/or provider refusal to discontinue aspirin. Results One hundred thirty-one eligible patients were contacted. Of those, 78 (60%) patients discontinued aspirin after speaking with the pharmacist, and 8 patients discontinued aspirin after a clinical pharmacist recommendation to the patient's primary care provider (PCP). The median time spent on outreach was approximately eight minutes. Of the 6 patients who consented to the project but declined to discontinue aspirin therapy based on pharmacist intervention, 5 preferred to discuss the issue with their PCP, while 1 patient was told by an outside provider to take aspirin. Conclusion Results indicate the successful impact a clinical pharmacist may have in deprescribing aspirin in a high-risk population. These data may also suggest that an active and intentional approach to deprescribing is likely to be more effective than a written recommendation to providers.

Low-dose aspirin for prevention of cardiovascular mortality in patients with type 2 diabetes and chronic kidney disease: A real-world nationwide cohort study.

Cardiovascular mortality risk is elevated among patients with diabetes and concurrent chronic kidney disease. However, controversy surrounds the use of aspirin for primary prevention within this population. This study aims to assess the effectiveness and safety of low-dose aspirin for primary prevention in patients with diabetes and pre-end-stage renal disease. This was a retrospective population-based cohort study using the National Health Insurance Research Database in Taiwan. The study included adults with type 2 diabetes who were enrolled in the pre-end-stage renal disease pay-for-performance program and had no atherosclerotic cardiovascular disease. We used propensity score analysis to control baseline characteristics between the two groups. Clinical outcomes including cardiovascular mortality, all-cause mortality, major bleeding, and renal disease progression were compared between patients who first received aspirin and those who did not. Between January 2012 and December 2015, a total of 2,155 low-dose aspirin users and 6,737 nonaspirin users were identified. Following propensity score adjustment, aspirin use exhibited a comparable risk of cardiovascular death compared with nonaspirin users (adjusted hazard ratio [aHR] 1.12; 95% confidence interval [CI] 0.65-1.95; P = 0.681). The risk of all-cause mortality was similar between the two groups (aHR 1.07; 95% CI 0.92-1.24; P = 0.385). Similar risks were observed in terms of major bleeding and renal disease progression. In patients with diabetes and pre-end-stage renal disease who lacked atherosclerotic cardiovascular disease, low-dose aspirin did not demonstrate a reduction in mortality. These findings do not support the use of aspirin for primary prevention in this high-risk population.

Association of low-dose aspirin use for primary prevention with self-reported kidney stones prevalence: a cross-sectional study.

To investigate the association between low-dose aspirin use for primary prevention and self-reported kidney stones prevalence in the 40-79years old population. We conducted a cross-sectional study based on the United States population data from the National Health and Nutrition Examination Survey 2011-2018. Baseline demographical and clinical data were collected. The univariate and multivariate regression was performed to identify confounding factors and assess the relationship between aspirin use for primary prevention and the prevalence of self-reported kidney stones. A propensity-score matching was used to identify patients with similar baseline characteristics to adjust for the bias caused by confounding factors. A total of 10,256 low-dose aspirin-use participants were included in this study. 10.4% of participants reported a history of kidney stones, and 18.5% reported a continuous use of low-dose prophylactic aspirin. Multivariate logistic regression analysis showed that low-dose preventive aspirin use had significantly increased the odds of self-reported kidney stones (OR = 1.245; 95% CI: 1.063-1.459; p = 0.007). In subgroup analysis, this finding was primarily limited to males (OR = 1.311), non-hypertensive participants (OR = 1.443), diabetic participants (OR = 1.380), and older (60 ≤ Age < 80) (OR = 1.349). The propensity-score matched analyses supported this result after adjusting for the bias caused by potential confounders (OR = 1.216; 95% CI: 1.011-1.462; p = 0.038). In this study, there exists a significant relationship between low-dose aspirin for primary prevention and self-reported kidney stones, primarily among males, no hypertensive participants, diabetics, or older adults. Further studies are needed to elucidate the mechanisms underlying these findings in the future.

Low-Dose Aspirin for Primary Prevention of Cardiovascular Events Comparing East Asians With Westerners: A Meta-Analysis

BackgroundEast Asians have shown different risk profiles for both thrombophilia and bleeding than Western counterparts. ObjectivesThe authors sought to evaluate the effect of low-dose aspirin for primary prevention between these populations. MethodsWe searched randomized clinical trials (RCTs) for intervention with low-dose aspirin (≤100 mg once daily) in participants without symptomatic cardiovascular disease until December 31, 2021. The number of events between the arms was extracted for analysis. Pooled risk ratios (RRs) and risk differences (RDs) were analyzed in each population. Outcomes included a major adverse cardiovascular event (MACE), cardiovascular death, myocardial infarction, stroke, and major bleeding (intracranial hemorrhage and major gastrointestinal bleeding). ResultsTwo RCTs included 17,003 East Asians, and 9 RCTs had 117,467 Western participants. Aspirin treatment showed a similar effect in reducing the MACE rate (RR of East Asians: 0.87; 95% CI: 0.71-1.05; RR of Westerners: 0.90; 95% CI: 0.85-0.95) (Pinteraction = 0.721). In contrast, the risk of major bleeding during aspirin vs control was greater in the East Asian population (RR: 2.48; 95% CI: 1.86-3.30) compared with the Western population (RR: 1.45; 95% CI: 1.26-1.66) (Pinteraction = 0.001), which was driven by more frequent gastrointestinal bleeding (RR of East Asians: 3.29; 95% CI: 2.26-4.80 vs RR of Westerners: 1.56; 95% CI: 1.29-1.88) (Pinteraction < 0.001). The net RDs (RD of MACE plus RD of major bleeding) were 8.04 and 0.72 per 1,000 persons in East Asian and Western participants, indicating 124 and 1,389 of the net number needed to harm, respectively. ConclusionsLow-dose aspirin for primary prevention in East Asians must be cautiously prescribed because of the increased risk of major bleeding relative to Western counterparts.

Aspirin for primary prevention of cardiovascular disease in women.

Aspirin use for primary prevention of cardiovascular disease is controversial. Low-dose aspirin may be considered for primary prevention in women on an individualized basis for those aged 40 to 59 years with a 10-year cardiovascular risk of 10% or more and without increased bleeding risk. Low-dose aspirin for primary prevention is not advised for low-risk women or women aged 60 years or older.

USPSTF concludes daily aspirin may hurt more than help, especially for older adults

USPSTF concludes daily aspirin may hurt more than help, especially for older adults

USPSTF updates recommendations on aspirin and CVD

New evidence is reshaping the role of low-dose aspirin in primary prevention. More selective decisions are now urged.

Benefits and Risks Associated with Low-Dose Aspirin Use for the Primary Prevention of Cardiovascular Disease: A Systematic Review and Meta-Analysis of Randomized Control Trials and Trial Sequential Analysis.

The role of aspirin in cardiovascular primary prevention remains controversial. Moreover, evidence for the potential benefits of aspirin in patients with high cardiovascular risk remains limited. The aim of this study was to explore the role of low-dose aspirin in primary prevention. The PubMed, EMBASE, Cochrane Library, and ClinicalTrials.gov databases were searched for randomized clinical trials (RCTs) from the date of inception to August 2021. The efficacy outcomes were major adverse cardiovascular events (MACE), myocardial infarction (MI), ischemic stroke (IS), all-cause mortality, and cardiovascular mortality, whereas safety outcomes were major bleeding, intracranial hemorrhage, and gastrointestinal (GI) bleeding. Subgroup analyses were based on different cardiovascular risks and diabetes statuses. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were calculated using the fixed- and random-effects models, and trial sequential analysis (TSA) was conducted to determine the robustness of the results. A total of 10 RCTs fulfilled the inclusion criteria. The use of aspirin was associated with a significant reduction in the risk of MACE (RR 0.89, 95% CI 0.84-0.93), MI (RR 0.86, 95% CI 0.78-0.95), and IS (RR 0.84, 95% CI 0.76-0.93); however, aspirin also increased the risk of safety outcomes, i.e. major bleeding (RR 1.42, 95% CI 1.26-1.60), intracranial hemorrhage (RR 1.33, 95% CI 1.11-1.59), and GI bleeding (RR 1.91, 95% CI 1.44-2.54). Subgroup analyses revealed that in the absence of a statistically significant interaction, a trend toward a net benefit of lower incidence of cardiovascular events (number needed to treat of MACE: high risk: 682 vs. low risk: 2191) and lesser risk of bleeding events (number needed to harm of major bleeding: high risk: 983 vs. low risk: 819) was seen in the subgroup of high cardiovascular risk. Meanwhile, the greater MACE reduction was also detected in the high-risk group of diabetes or nondiabetes patients. Furthermore, a post hoc subgroup analysis indicated a significant rate reduction in patients aged ≤70 years but not in patients aged >70 years. TSA confirmed the benefit of aspirin for MACE up to a relative risk reduction of 10%. The current study demonstrated that the cardiovascular benefits of low-dose aspirin were equally balanced by major bleeding events. In addition, the potential beneficial effects might be seen in the population ≤70 years of age with high cardiovascular risk and no increased risk of bleeding.

Low-dose aspirin for primary prevention of adverse pregnancy outcomes in twin pregnancies: an observational cohort study based on propensity score matching

BackgroundSince the effectiveness of low-dose aspirin (LDA) in twin pregnancies is uncertain, we aimed to preliminarily assess whether LDA is beneficial in preventing preeclampsia in twin pregnancies.MethodsThis study is an observational study in two hospitals in China. Among 932 women, 277 in the First Affiliated Hospital of Chongqing Medical University were routinely treated with aspirin (100 mg daily) from 12 to 16 weeks to 35 weeks of gestational age, while 655 in Chongqing Health Center for Women and Children were not taking aspirin during pregnancy. We followed each subject and the individual details were recorded.ResultsLDA significantly reduced the risk of preeclampsia (RR 0.48; 95% CI 0.24–0.95) and preterm birth 34 weeks (RR 0.50; 95% CI 0.29–0.86) and showed possible benefits to lower the rate of SGA babies (RR 0.74; 95% CI 0.55–1.00). Moreover, the risk of postpartum hemorrhage was not increased by LDA (RR 0.89; 95% CI 0.35–2.26).ConclusionsTreatment with low-dose aspirin in twin pregnancies could offer some protection against adverse pregnancy outcomes in the absence of significantly increased risk of postpartum hemorrhage.Trial registrationChinese Clinical Trial Registry (ChiCTR); ChiCTR-OOC-16008203, Retrospectively registered date: April 1st, 2016;

Low-dose aspirin for primary prevention of cardiovascular disease: Trends in use patterns among African American adults in Minnesota, 2015–2019

Cardiovascular disease (CVD) disproportionately affects African Americans. Aspirin has long been recommended to reduce cardiovascular events. However, national guideline changes in 2016 limited the aspirin recommended population and several clinical trials questioning the utility of primary prevention aspirin were published in 2018. In light of the recent guidelines and study findings, we investigated primary prevention aspirin use among urban African American adults. Using three cross-sectional surveys, we collected data from self-identified African Americans with no CVD in 2015, 2017 and 2019, querying information on CVD risk factors, health behaviors and beliefs, and aspirin use. Poisson regression modeling was used to estimate age- and risk-factor adjusted aspirin prevalence, trends and associations. A total of 1491 African Americans adults, ages 45–79, were included in this analysis; 61% were women. There was no change in age- and risk factor-adjusted aspirin use over the 3 surveys for women (37%, 34% and 35% respectively) or men (27%, 25%, 30% respectively). However, fewer participants believed aspirin was helpful in 2019 compared to 2015—75% versus 84% (p < 0.001). Aspirin discussions with a health care practitioner were highly associated with aspirin use (adjusted RR 2.97, 95% CI 2.49–3.54) and aspirin use was 2.56 times higher (adjusted RR 95% CI 2.17–3.03) in respondents who agreed that people close to them thought they should take aspirin compared with those who disagreed or did not know. Despite major changes in national guidelines, overall primary prevention aspirin use did not significantly change in these African American samples from 2015 to 2019.

A community-based group randomized trial to increase aspirin use for primary prevention of cardiovascular disease: Study protocol and baseline results for the “Ask About Aspirin” initiative

BackgroundUSPSTF evidence-based recommendations for the use of low-dose aspirin for primary prevention of cardiovascular disease were published in 2009. We describe a statewide campaign using innovative methods to educate the public and health communities about appropriate aspirin use. Methods/designThe “Ask About Aspirin” initiative is designed to lower the number of first heart attacks and strokes in the State of Minnesota by promoting the appropriate use of low dose aspirin. A health system intervention combined with an aspirin awareness media campaign will be evaluated in a pragmatic group randomized controlled trial including 267 primary care clinics within 84 health systems over a four year period. Matched pairs of geographic territories will be randomized to intervention (12 territories) or control (12 territories). The primary outcome of appropriate aspirin use will be measured at the individual level, by community-based telephone surveys of 100 participants in each of the 24 geographically determined clusters. DiscussionWe briefly describe the rationale for the interventions being studied, as well as the major design choices. Rigorous research designs such as the one described here are necessary to determine whether evidence-based recommendations can be effectively disseminated in multiple health systems. Trial registrationClinicalTrials.gov: NCT02607917.

Low-dose Aspirin for Primary Prevention of Cardiovascular Events in Postmenopausal Women with Type-2 Diabetes: The Prescriptive Approach in the Real World.

Background:The long-term efficacy of low-dose aspirin for primary prevention of cardiovascular (CV) events in postmenopausal women with type-2 diabetes is controversial. Therefore, it is recommended only on an individual basis, recommendation of grade C.Methods:We enrolled 275 consecutive postmenopausal women with type-2 diabetes, without an increased bleeding risk and without preexisting CV disease as coronary artery disease, stroke, and peripheral vascular disease, but with a high risk assessed by score >10%, aged 60–69 years. All were receiving aspirin (75–100 mg daily), aspirin group (AG). 170 postmenopausal women with type-2 diabetes and without preexisting cardiovascular (CV) disease, but not on aspirin treatment, despite a high risk assessed by score >10%, were control group (CG). Mean age was 66 ± 4 years for AG and 65 ± 7 years for CG. Our goal was to identify the prevalence of low-dose aspirin prescriptions in these populations according to different clinical conditions.Results:Women with only high risk were 41/275 (15%) on AG and 72/170 (42.3%) on CG, Chi-squared 41, Odds ratio 0.2, c.i. 95%, P < 0.0001. Women affected by metabolic syndrome were 105/275 (38.1%) on AG and 47/170 (27.6%) on CG, Chi-squared 5.1, Odds ratio 1.6, c.i. 95%, P < 0.02. Women affected by metabolic cardiomyopathy were 111/275 (40.3%) on AG and 44/170 (25.9%) on CG, Chi-squared 8, Odds ratio 1.8, c.i. 95%, P < 0.004. Women affected by diabetic cardiomyopathy were 18/275 (6.6%) on AG and 7/170 (4.2%) on CG, Chi-squared 1.2, Odds ratio 16, c.i. 95%, P < 0.2 n.s.Conclusions:Low-dose aspirin in our population is prescribed preferentially in postmenopausal women with type-2 diabetes when affected by metabolic syndrome or metabolic cardiomyopathy, at the opposite women with only high risk have lower chance to receive aspirin.

Caution Regarding Low-Dose Aspirin for Primary Prevention of Cardiovascular Events.

According to this study.

A Practical Approach to Low-Dose Aspirin for Primary Prevention

A Practical Approach to Low-Dose Aspirin for Primary Prevention

Aspirin for primary prevention of cardiovascular disease in diabetes.

Aspirin for primary prevention of cardiovascular disease in diabetes.

Low-Dose Aspirin for Primary Prevention of Cardiovascular Events in Elderly Japanese Patients with Atherosclerotic Risk Factors: Subanalysis of a Randomized Clinical Trial (JPPP-70).

This post hoc subanalysis of the randomized Japanese Primary Prevention Project investigated whether once-daily low-dose aspirin versus no aspirin reduced the risk of cardiovascular events (CVEs) in patients aged ≥ 70years with atherosclerotic risk factors. Patients aged < 70years (young-old) or ≥ 70years (old) with hypertension, dyslipidemia, or diabetes participated between 2005 and 2007. Patients were randomized 1:1 to receive 100mg enteric-coated aspirin once daily or no aspirin plus standard of care. The primary outcome was a composite of death from cardiovascular causes plus nonfatal stroke and nonfatal myocardial infarction. The secondary outcome was a composite of the primary outcome plus transient ischemic attack, angina pectoris, and arteriosclerotic disease requiring medical or surgical intervention. Old (n = 7971) and young-old (n = 6493) patients were followed up for a median 5.02years. Aspirin did not reduce the risk of primary (hazard ratio [HR] 0.92 [95% confidence interval {CI} 0.74-1.16]; P = 0.50) or secondary (0.85 [0.70-1.04]; P = 0.11) outcomes in patients aged ≥ 70years. In old men with high-density lipoprotein < 40mg/dL, treatment with low-dose aspirin was associated with a reduction in the incidence of the primary endpoint compared with the group not receiving aspirin (10/260 vs 22/250; HR 0.44 [95% CI 0.20-0.93]; P = 0.03). This subgroup was also found to contain significant larger proportions of patients with elevated body mass index, patients with diabetes mellitus, and smokers (P < 0.001). Old patients also showed differences in bleeding outcomes. Serious extracranial hemorrhage requiring transfusion or hospitalization occurred significantly more frequently in the aspirin-treated group than in the non-aspirin-treated group (35 [0.88%] vs 18 [0.45%]; HR 1.96 [1.11-3.46]; P = 0.020). Gastrointestinal hemorrhage occurred significantly more frequently in the aspirin-treated group than the non-aspirin-treated group (63 [1.58%] vs 18 [0.45%]; relative risk [RR] 3.5 [2.08-5.90]; P < 0.0001). Cerebral hemorrhage (intracranial hemorrhage) tended to occur more frequently in the aspirin-treated group than the non-aspirin-treated group (22 [0.55%] vs 11 [0.28%]; RR 2.01 [0.97-4.14]; P = 0.058). Cerebral hemorrhage occurred significantly more frequently in old patients than in young-old patients (33 [0.41%] vs 10 [0.15%]; HR 2.7 [1.34-5.53]; P = 0.0055). Gastrointestinal hemorrhage occurred in a slightly higher proportion of old patients compared with young-old patients (81 [1.02%] vs 53 [0.82%]; RR 1.2 [0.88-1.76]; P = 0.21). Aspirin did not reduce the risk of the primary or secondary outcomes in old patients. Aspirin treatment may have reduced CVEs within a high CVE risk elderly population subgroup. Aspirin treatment in such a group requires caution, because of the increased risk of intracranial hemorrhage, severe extracranial hemorrhage requiring hospitalization or transfusion, and gastrointestinal bleeding in old patients receiving aspirin therapy. The study is registered at ClinicalTrials.gov [NCT00225849].

Antithrombotic Agents and Cancer.

Platelet activation is the first response to tissue damage and, if unrestrained, may promote chronic inflammation-related cancer, mainly through the release of soluble factors and vesicles that are rich in genetic materials and proteins. Platelets also sustain cancer cell invasion and metastasis formation by fostering the development of the epithelial-mesenchymal transition phenotype, cancer cell survival in the bloodstream and arrest/extravasation at the endothelium. Furthermore, platelets contribute to tumor escape from immune elimination. These findings provide the rationale for the use of antithrombotic agents in the prevention of cancer development and the reduction of metastatic spread and mortality. Among them, low-dose aspirin has been extensively evaluated in both preclinical and clinical studies. The lines of evidence have been considered appropriate to recommend the use of low-dose aspirin for primary prevention of cardiovascular disease and colorectal cancer by the USA. Preventive Services Task Force. However, two questions are still open: (i) the efficacy of aspirin as an anticancer agent shared by other antiplatelet agents, such as clopidogrel; (ii) the beneficial effect of aspirin improved at higher doses or by the co-administration of clopidogrel. This review discusses the latest updates regarding the mechanisms by which platelets promote cancer and the efficacy of antiplatelet agents.

ASS-Primärprophylaxe bei Diabetikern ohne Effekt

Saito Y et al. Low-Dose Aspirin for Primary Prevention of Cardiovascular Events in Patients With Type 2 Diabetes Mellitus: 10-Year Follow-Up of a Randomized Controlled Trial. Circulation 2017; 135: 659–670

Low-Dose Aspirin for Primary Prevention of Cardiovascular Events in Patients With Type 2 Diabetes Mellitus: 10-Year Follow-Up of a Randomized Controlled Trial.

The long-term efficacy and safety of low-dose aspirin for primary prevention of cardiovascular events in patients with type 2 diabetes mellitus are still inconclusive. The JPAD trial (Japanese Primary Prevention of Atherosclerosis With Aspirin for Diabetes) was a randomized, open-label, standard care-controlled trial examining whether low-dose aspirin affected cardiovascular events in 2539 Japanese patients with type 2 diabetes mellitus and without preexisting cardiovascular disease. Patients were randomly allocated to receive aspirin (81 or 100 mg daily; aspirin group) or no aspirin (no-aspirin group) in the JPAD trial. After that trial ended in 2008, we followed up with the patients until 2015, with no attempt to change the previously assigned therapy. Primary end points were cardiovascular events, including sudden death, fatal or nonfatal coronary artery disease, fatal or nonfatal stroke, and peripheral vascular disease. For the safety analysis, hemorrhagic events, consisting of gastrointestinal bleeding, hemorrhagic stroke, and bleeding from any other sites, were also analyzed. The primary analysis was conducted for cardiovascular events among patients who retained their original allocation (a per-protocol cohort). Analyses on an intention-to-treat cohort were conducted for hemorrhagic events and statistical sensitivity. The median follow-up period was 10.3 years; 1621 patients (64%) were followed up throughout the study; and 2160 patients (85%) retained their original allocation. Low-dose aspirin did not reduce cardiovascular events in the per-protocol cohort (hazard ratio, 1.14; 95% confidence interval, 0.91-1.42). Multivariable Cox proportional hazard model adjusted for age, sex, glycemic control, kidney function, smoking status, hypertension, and dyslipidemia showed similar results (hazard ratio, 1.04; 95% confidence interval, 0.83-1.30), with no heterogeneity of efficacy in subgroup analyses stratified by each of these factors (all interaction P>0.05). Sensitivity analyses on the intention-to-treat cohort yielded consistent results (hazard ratio, 1.01; 95% confidence interval, 0.82-1.25). Gastrointestinal bleeding occurred in 25 patients (2%) in the aspirin group and 12 (0.9%) in the no-aspirin group (P=0.03), and the incidence of hemorrhagic stroke was not different between groups. Low-dose aspirin did not affect the risk for cardiovascular events but increased risk for gastrointestinal bleeding in patients with type 2 diabetes mellitus in a primary prevention setting. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00110448.