title: Renin-angiotensin system blockade for the risk of cancer and death.
abstract: BACKGROUND
  The effects of renin-angiotensin system blockade with angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II type 1 receptor blockers (ARBs) on cancer remain inconsistent.
  
  
  METHODS
  We searched existing databases from 1960 to August 2015, for randomised controlled trials and observational studies (case-control studies and cohort studies) of ARB/ACEI therapy with a minimal one year of follow-up. Outcomes were incidence and mortality of cancer.
  
  
  RESULTS
  We included 14 randomised controlled trials and 17 observational studies of 3,957,725 participants (350,329 ARB/ACEI users). The users had a lower incidence of cancer in the observational studies (RR 0.82, 95% CI 0.73-0.93) but not in the randomised controlled trials (RR 1.00, 95% CI 0.92-1.08). The protection persisted for lung cancer (RR 0.85, 95% CI 0.75-0.97) but not for other sites of cancer. The relative risk of cancer associated with renin-angiotensin system blockade was reduced along with time of follow-up. Mortality reduction with ARB/ACEI was marginally significant in the observational studies (RR 0.71, 95% CI 0.55-0.93) but not in the randomised controlled trials (RR 0.99, 95% CI 0.89-1.09).
  
  
  CONCLUSIONS
  The significant benefits of renin-angiotensin system blockade observed in case-control studies and cohort studies might diminish in randomised controlled trials. Clinical design, site of cancer and duration of follow-up may affect the clinical outcomes.
authors.affiliation: Center for Diabetic Systems Medicine, Guilin Medical University, China Department of Pathology, Affiliated Hospital of Guilin Medical University, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Shen
authors.affiliation: Center for Diabetic Systems Medicine, Guilin Medical University, China.
authors.forename: Yan-Mei
authors.initials: YM
authors.lastname: Huang
authors.affiliation: Center for Diabetic Systems Medicine, Guilin Medical University, China.
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.affiliation: Department of Rheumatology and Immunology, Affiliated Hospital of Guilin Medical University, China.
authors.forename: Xue-Zhi
authors.initials: XZ
authors.lastname: Hong
authors.affiliation: Department of Anesthetics, Affiliated Hospital of Guilin Medical University, China.
authors.forename: Xin-Nan
authors.initials: XN
authors.lastname: Song
authors.affiliation: Center for Diabetic Systems Medicine, Guilin Medical University, China.
authors.forename: Xia
authors.initials: X
authors.lastname: Zou
authors.affiliation: Center for Diabetic Systems Medicine, Guilin Medical University, China.
authors.forename: Yan-Hong
authors.initials: YH
authors.lastname: Pan
authors.affiliation: Center for Diabetic Systems Medicine, Guilin Medical University, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Ling
authors.affiliation: Center for Diabetic Systems Medicine, Guilin Medical University, China.
authors.forename: Min-Hui
authors.initials: MH
authors.lastname: Zhu
authors.affiliation: Center for Diabetic Systems Medicine, Guilin Medical University, China.
authors.forename: Xiao-Xi
authors.initials: XX
authors.lastname: Zhang
authors.affiliation: Center for Diabetic Systems Medicine, Guilin Medical University, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Sui
authors.affiliation: Center for Diabetic Systems Medicine, Guilin Medical University, China zhaohailu9@126.com zhaohailu@yahoo.com.
authors.forename: Hai-Lu
authors.initials: HL
authors.lastname: Zhao
mesh_terms: D047228:Angiotensin II Type 1 Receptor Blockers / Q000627:therapeutic use; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D006801:Humans; D009369:Neoplasms / Q000188:drug therapy* / Q000401:mortality*; D064887:Observational Studies as Topic; D017594:Publication Bias; D016032:Randomized Controlled Trials as Topic; D012084:Renin-Angiotensin System; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors
keywords: Angiotensin-converting enzyme inhibitors; angiotensin II receptor blockers; angiotensin-receptor blocker; cancer; renin–angiotensin system