Gout and Risk of Myocardial Infarction: A Systematic Review and Meta-Analysis of Cohort Studies

Introduction
A high incidence of myocardial infarction among patients with gout has been suggested by several observational studies. We performed a meta-analysis to evaluate the association between gout and the risk of myocardial infarction.
Materials and Methods
The PubMed and Embase databases were searched from inception to October 2014 for cohort studies that evaluating the association between gout and the risk of myocardial infarction. Summary estimates were derived using a random-effects model and reported as relative risks (RRs) with 95% confidence intervals (CIs).
Results
Five studies involving 8,656,413 participants with a total of 1000 MI events were included. Overall, gout was associated with an increased risk of myocardial infarction (RR 1.45; 95% CI, 1.19–1.75; p<0.001), and the association referred to non-fatal myocardial infarction (RR 1.29; 95% CI, 1.19–1.39; p <0.001) but not fatal myocardial infarction (RR 1.11; 95% CI, 0.96–1.28; p = 0.174). The increased risk was observed in both women (RR 1.62; 95% CI, 1.18–2.21; p = 0.003) and men (RR 1.45; 95% CI, 1.21–1.74; p <0.001). Stratified analysis revealed a gradual increase in myocardial infarction risk with a younger age of gout onset (age 20–44 years old (RR 2.82; 95% CI, 1.38–5.79; p = 0.05); 45–69 years old (RR 1.85; 95% CI, 1.22–2.82; p = 0.04); ≥70 years old (RR 1.52; 95% CI, 1.22–1.88; p <0.001)).
Conclusion
This meta-analysis suggests that patients with gout have an increased risk of myocardial infarction.