Anemia and mortality in acute coronary syndromes: A systematic review and meta-analysis.
Am Heart J. 2013 Feb;165(2):143-153.e5
Authors: Lawler PR, Filion KB, Dourian T, Atallah R, Garfinkle M, Eisenberg MJ
BACKGROUND: Anemia is a common comorbidity among patients with acute coronary syndromes (ACS) and may adversely affect cardiovascular outcomes in these patients. We conducted a systematic review and meta-analysis to examine the association between anemia and mortality among patients with ACS.
METHODS: We systematically searched MEDLINE to identify cohort studies and secondary analyses of randomized controlled trials examining the association between anemia and all-cause mortality among patients with ACS. Data were aggregated at 4 follow-up times (inhospital, 30 days, 1 year, and maximal available follow-up) using random-effects meta-analysis models.
RESULTS: Twenty-seven studies met the inclusion criteria, involving 233,144 patients. Anemia was present in 44,519 (19.1%) of these patients. Anemic patients were generally older and had a higher prevalence of comorbidities including diabetes mellitus, congestive heart failure, cerebrovascular disease, and history of major bleeding. Anemia was associated with an increased risk of crude all-cause mortality (relative risk 2.08, 95% CI 1.70-2.55) and reinfarction (relative risk 1.25, 95% CI 1.02-1.53) at maximal available follow-up. When adjusted risk ratios from individual studies' multivariable regression analyses were pooled, the magnitude of the associated mortality risk was attenuated but remained significant at maximal follow-up (hazard ratio 1.49, 95% CI 1.23-1.81). Clinically and statistically significant increases in mortality were observed as early as at 30 days post-ACS and persisted at 1 year.
CONCLUSIONS: Anemia in patients with ACS is independently associated with a significantly increased risk of early and late mortality.
PMID: 23351816 [PubMed - in process]