Inflammatory bowel disease is not a risk factor for cardiovascular disease mortality: results from a systematic review and meta-analysis

OBJECTIVES: Inflammation in general, and C-reactive protein (CRP) in particular, are closely associated with atherosclerosis. Similarly, the risk of cardiovascular (CV) disease is increased in several systemic inflammatory diseases. The purpose of this study was to examine whether inflammatory bowel disease (IBD) increases CV mortality, an indirect surrogate for CV disease incidence. METHODS: A systematic review of studies on CV mortality rates in patients with IBD published between 1965 and 2006 was performed. Studies were included for analysis if they reported data on CV-disease-specific standardized mortality ratios (SMRs) for Crohn's disease (CD) and/or ulcerative colitis (UC). A meta-analysis of SMRs from included studies was performed. RESULTS: The review ultimately included 11 studies. Overall there were 4,532 patients with CD and 9,533 patients with UC. SMR point estimates ranged from 0.7 to 1.5 for patients with CD and 0.6-1.1 for patients with UC. There was not a statistically significant increase in CV SMR for either CD or UC in any study. However, two studies demonstrated a statistically significant decrease in CV SMR for UC. Finally, the meta-SMR for CD was 1.0 (95% CI 0.8-1.1) and the meta-SMR for UC was 0.9 (95% CI 0.8-1.0). CONCLUSIONS: IBD is not associated with increased CV mortality. Although CV mortality is a suboptimal surrogate for CV disease incidence, this finding provides indirect evidence against an association between IBD and CV disease.