Risk of incident cardiovascular events in patients with rheumatoid arthritis: a meta-analysis of observational studies

Objective To determine the magnitude of the risk of incident cardiovascular disease (CVD; fatal and non-fatal), including acute myocardial infarction (MI), cerebrovascular accidents (CVA) and congestive heart failure (CHF), in patients with rheumatoid arthritis (RA) compared to the general population through a meta-analysis of controlled observational studies. Methods The authors searched the Medline, Embase, LILACS and Cochrane databases from their inception to June 2011. Observational studies meeting the following criteria were included: (1) prespecified RA criteria; (2) predefined CVD criteria for incident CVD (MI, CVA or CHF); (3) a comparison group; and (4) RR estimates, 95% CI or data for calculating them. The authors calculated the pooled RR using the random-effects model and tested for heterogeneity using the bootstrap version of the Q statistic. Results Fourteen studies comprising 41 490 patients met the inclusion criteria. Overall, there was a 48% increased risk of incident CVD in patients with RA (pooled RR 1.48 (95% CI 1.36 to 1.62)). The risks of MI and CVA were increased by 68% (pooled RR 1.68 (95% CI 1.40 to 2.03)) and 41% (pooled RR 1.41 (95% CI 1.14 to 1.74)). The risk of CHF was assessed in only one study (RR 1.87 (95% CI 1.47 to 2.39)). Significant heterogeneity existed in all main analyses. Subgroup analyses showed that inception cohort studies were the only group that did not show a significantly increased risk of CVD (pooled RR 1.12 (95% CI 0.97 to 1.65)). Conclusions Published data indicate that the risk of incident CVD is increased by 48% in patients with RA compared to the general population. Sample and cohort type influenced the estimates of RR.