title: Renin-angiotensin system inhibitors linked to anemia: a systematic review and meta-analysis.
abstract: BACKGROUND
  The objective of this meta-analysis was to evaluate the risk of anemia in patients who received renin-angiotensin system (RAS) inhibitors.
  
  
  METHODS
  A literature search was performed using MEDLINE, EMBASE, and Cochrane Database of Systematic Reviews from inception through November, 2014. Studies that reported relative risks, odd ratios or hazard ratios comparing the anemia risk in patients who received angiotensin-converting-enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) vs. those who did not were included. We performed the prespecified sensitivity analysis including only only studies with confounder adjusted analysis. Pooled risk ratios (RRs) and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method.
  
  
  RESULTS
  Seven studies (2 cohort and 5 cross-sectional studies) with 29,061 patients were included in the analysis to assess the risk of anemia and the RAS inhibitors use. The pooled RR of anemia in patients receiving ACEIs was 1.56 (95% CI, 1.40-1.73, I(2) = 17%). When meta-analysis was limited only to studies with confounder adjusted analysis, the pooled RR of anemia in patients using ACEIs was 1.57 (95% CI, 1.43-1.73, I(2) = 0%) The pooled RR of anemia in patients receiving ARBs was 1.60 (95% CI, 1.27-2.00, I(2) = 39%). The meta-analysis of studies with confounder adjusted analysis demonstrated the pooled RR of anemia in patients using ARBs of 1.59 (95% CI, 1.38-1.83, I(2) = 0%).
  
  
  CONCLUSIONS
  Our meta-analysis demonstrates an association between anemia and the use of RAS inhibitors. Hematological parameters should be monitored in patients treated with RAS inhibitors.
authors.affiliation: From the Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, USA, wcheungpasitporn@gmail.com.
authors.forename: W
authors.initials: W
authors.lastname: Cheungpasitporn
authors.affiliation: From the Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: C
authors.initials: C
authors.lastname: Thongprayoon
authors.affiliation: Department of Internal Medicine, Chulalongkorn University, Bangkok, Thailand and.
authors.forename: T
authors.initials: T
authors.lastname: Chiasakul
authors.affiliation: Department of Internal Medicine, MetroWest Medical Center, Framingham, MA, USA.
authors.forename: S
authors.initials: S
authors.lastname: Korpaisarn
authors.affiliation: From the Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: S B
authors.initials: SB
authors.lastname: Erickson
mesh_terms: D000740:Anemia / Q000139:chemically induced*; D057911:Angiotensin Receptor Antagonists / Q000009:adverse effects*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects*; D002318:Cardiovascular Diseases / Q000150:complications; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D016030:Kidney Transplantation / Q000009:adverse effects; D008297:Male
chemical_list: D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors