Dataset Information

Association of Aspirin Use for Primary Prevention With Cardiovascular Events and Bleeding Events: A Systematic Review and Meta-analysis.

ABSTRACT:

Importance

The role for aspirin in cardiovascular primary prevention remains controversial, with potential benefits limited by an increased bleeding risk.

Objective

To assess the association of aspirin use for primary prevention with cardiovascular events and bleeding.

Data sources

PubMed and Embase were searched on Cochrane Library Central Register of Controlled Trials from the earliest available date through November 1, 2018.

Study selection

Randomized clinical trials enrolling at least 1000 participants with no known cardiovascular disease and a follow-up of at least 12 months were included. Included studies compared aspirin use with no aspirin (placebo or no treatment).

Data extraction and synthesis

Data were screened and extracted independently by both investigators. Bayesian and frequentist meta-analyses were performed.

Main outcomes and measures

The primary cardiovascular outcome was a composite of cardiovascular mortality, nonfatal myocardial infarction, and nonfatal stroke. The primary bleeding outcome was any major bleeding (defined by the individual studies).

Results

A total of 13 trials randomizing 164 225 participants with 1 050 511 participant-years of follow-up were included. The median age of trial participants was 62 years (range, 53-74), 77 501 (47%) were men, 30 361 (19%) had diabetes, and the median baseline risk of the primary cardiovascular outcome was 9.2% (range, 2.6%-15.9%). Aspirin use was associated with significant reductions in the composite cardiovascular outcome compared with no aspirin (57.1 per 10 000 participant-years with aspirin and 61.4 per 10 000 participant-years with no aspirin) (hazard ratio [HR], 0.89 [95% credible interval, 0.84-0.95]; absolute risk reduction, 0.38% [95% CI, 0.20%-0.55%]; number needed to treat, 265). Aspirin use was associated with an increased risk of major bleeding events compared with no aspirin (23.1 per 10 000 participant-years with aspirin and 16.4 per 10 000 participant-years with no aspirin) (HR, 1.43 [95% credible interval, 1.30-1.56]; absolute risk increase, 0.47% [95% CI, 0.34%-0.62%]; number needed to harm, 210).

Conclusions and relevance

The use of aspirin in individuals without cardiovascular disease was associated with a lower risk of cardiovascular events and an increased risk of major bleeding. This information may inform discussions with patients about aspirin for primary prevention of cardiovascular events and bleeding.

SUBMITTER: Zheng SL

PROVIDER: S-EPMC6439678 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:BackgroundCurrent evidence from randomized controlled trials on statins for primary prevention of cardiovascular disease (CVD) in older people, especially those aged > 75 years, is still lacking. We conducted a systematic review and meta-analysis of observational studies to extend the current evidence about the association of statin use in older people primary prevention group with risk of CVD and mortality.MethodsPubMed, Scopus, and Embase were searched from inception until March 18, 2021. We included observational studies (cohort or nested case-control) that compared statin use vs non-use for primary prevention of CVD in older people aged ≥ 65 years; provided that each of them reported the risk estimate on at least one of the following primary outcomes: all cause-mortality, CVD death, myocardial infarction (MI), and stroke. Risk estimates of each relevant outcome were pooled as a hazard ratio (HR) with a 95% confidence interval (CI) using the random-effects meta-analysis model. The quality of the evidence was rated using the GRADE approach.ResultsTen observational studies (9 cohorts and one case-control study; n = 815,667) fulfilled our criteria. The overall combined estimate suggested that statin therapy was associated with a significantly lower risk of all-cause mortality (HR: 0.86 [95% CI 0.79 to 0.93]), CVD death (HR: 0.80 [95% CI 0.78 to 0.81]), and stroke (HR: 0.85 [95% CI 0.76 to 0.94]) and a non-significant association with risk of MI (HR 0.74 [95% CI 0.53 to 1.02]). The beneficial association of statins with the risk of all-cause mortality remained significant even at higher ages (> 75 years old; HR 0.88 [95% CI 0.81 to 0.96]) and in both men (HR: 0.75 [95% CI: 0.74 to 0.76]) and women (HR 0.85 [95% CI 0.72 to 0.99]). However, this association with the risk of all-cause mortality remained significant only in those with diabetes mellitus (DM) (HR 0.82 [95% CI 0.68 to 0.98]) but not in those without DM. The level of evidence of all the primary outcomes was rated as "very low."ConclusionsStatin therapy in older people (aged ≥ 65 years) without CVD was associated with a 14%, 20%, and 15% lower risk of all-cause mortality, CVD death, and stroke, respectively. The beneficial association with the risk of all-cause mortality remained significant even at higher ages (> 75 years old), in both men and women, and in individuals with DM, but not in those without DM. These observational findings support the need for trials to test the benefits of statins in those above 75 years of age.

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