Intended for healthcare professionals

Student Research explained

Meta-analysis: aspirin for patients with diabetes

BMJ 2010; 341 doi: (Published 10 August 2010) Cite this as: BMJ 2010;341:c4103
  1. Mamas A Mamas, clinical lecturer in cardiology12,
  2. Ludwig Neyses, professor of medicine and cardiology12
  1. 1Manchester Heart Centre, Manchester Royal Infirmary, Manchester
  2. 2Manchester Academic Health Science Centre, University of Manchester, Manchester

Can aspirin be used as a primary prevention for cardiovascular events?

The paper

  • “Aspirin for primary prevention of cardiovascular events in people with diabetes: meta-analysis of randomised controlled trials” by Giorgia De Berardis and colleagues (BMJ 2009;339:b4531, doi:10.1136/bmj.b4531).


  • Objectives—To evaluate the benefits and harms of low dose aspirin in people with diabetes and no cardiovascular disease.

  • Design—Meta-analysis of randomised controlled trials.

  • Data sources—Medline (1966-November 2008), the Cochrane central register of controlled trials (Cochrane Library 2008; issue 4), and reference lists of retrieved articles.

  • Review methods—Randomised trials of aspirin compared with placebo or no aspirin in people with diabetes and no pre-existing cardiovascular disease were eligible for inclusion. Data on major cardiovascular events (death from cardiovascular causes, non-fatal myocardial infarction, non-fatal stroke, and all cause mortality) were extracted and pooled with a random effect model. Results are reported as relative risks with 95% confidence intervals.

  • Results—Of 157 studies in the literature searches, six were eligible (10 117 participants). When aspirin was compared with placebo there was no statistically significant reduction in the risk of major cardiovascular events (five studies, 9584 participants; relative risk 0.90, 95% confidence interval 0.81 to 1.00), cardiovascular mortality (four studies, n=8557, 0.94; 0.72 to 1.23), or all cause mortality (four studies, n=8557; 0.93, 0.82 to 1.05). Significant heterogeneity was found in the analysis for myocardial infarction (I2=62.2%; P=0.02) and stroke (I2=52.5%; P=0.08). Aspirin significantly reduced the risk of myocardial infarction in men (0.57, 0.34 to 0.94) but not in women (1.08, 0.71 to 1.65; P for interaction=0.056). Evidence relating to harms was inconsistent.

  • Conclusions—A clear benefit of aspirin in the primary prevention of major cardiovascular events in people with diabetes remains unproved. Sex may be an important effect modifier. Toxicity is to be explored further.

Why do the study?

Aspirin is one of the most commonly …

View Full Text

Log in

Log in through your institution


* For online subscription