Background: The present study was aimed at determining whether the sporadic intake of acetylsalicylic acid (ASA) shows a protective effect on the appearance or attenuation of coronary disease events.
Methods: The analysis was based on articles found in EMBASE, MEDLINE and the Cochrane Library. Scientific rigour was further assessed. We looked for original articles with clinical trial, cohorts, and case-control or cross-sectional study designs, where the effect could be assessed by the odds ratio (OR).
Results: A meta-analysis showed a protective effect of sporadic ASA intake on the prevention of acute myocardial infarction (OR for fixed effects = 0.75, CI 95%, 0.63-0.88, p < 0.0006), which was more important in men than in women, and on the prevention of cardiovascular mortality (OR for fixed effects = 0.61, CI 95%, 0.59-0.64, p < 0.0001). However, overall mortality was found to be higher in those groups receiving the drug (OR for fixed effects = 1.20, CI 95%, 1.05-1.37, p = 0.0006). None of these effects was significant when performing a random effect analysis. ASA also attenuated acute coronary syndromes (OR for fixed effects = 0.34, CI 95%, 0.26-0.45, p < 0.0001).
Conclusions: These results suggest that the sporadic intake of ASA may have a protective particularly in men and attenuating effect on acute myocardial infarction, in addition to playing a role in preventing cardiovascular mortality but not overall mortality. Further studies to confirm these effects are warranted.