A meta-analysis of circulating homocysteine levels in subjects with versus without abdominal aortic aneurysm.

The aim of this paper was to summarize the present evidence for an association between circulating total homocysteine (tHcy) levels and abdominal aortic aneurysm (AAA) presence, we performed a meta-analysis. MEDLINE and EMBASE were searched through December 2013. Search terms included homocysteine, hyperhomocysteinemia, hyperhomocysteinaemia, and abdominal aortic aneurysm. Eligible studies were case-control or population-screening studies reporting circulating tHcy levels in cases with AAA and subjects without AAA. For each study, data regarding plasma or serum tHcy levels in both the AAA and control groups were used to generate standardized mean differences (SMDs) and 95% confidence intervals (CIs). Further, adjusted and unadjusted odds ratios (ORs) with 95% CI of AAA incidence for subjects with hyperhomocysteinemia were extracted. Of 42 potentially relevant articles screened initially, 9 eligible studies enrolling 1643 cases with AAA and 5460 subjects without AAA were identified and included. A pooled analysis demonstrated significantly greater circulating tHcy levels in the AAA than control group (SMD, 0.58; 95% CI, 0.36 to 0.79; P<0.00001). Another pooled analysis demonstrated a statistically significant 3.1-fold increase in AAA incidence for subjects with hyperhomocysteinemia (OR, 3.07; 95% CI, 1.59 to 5.92; P=0.0008). In conclusion, greater circulating tHcy levels are associated with AAA presence.