title: Relationship between the use of statins and patient survival in colorectal cancer: a systematic review and meta-analysis.
abstract: BACKGROUND
  Studies have indicated that statins influence the risks and mortality rates of several types of solid tumors. However, the association between statin use and survival in patients with colorectal cancer (CRC) remains unclear.
  
  
  METHODS
  We searched the PubMed and Embase databases for relevant studies published up to September 2014 that assessed statin use and CRC prognosis. The primary outcomes were overall survival (OS) and cancer-specific survival (CSS). The secondary outcomes were disease-free survival (DFS) and recurrence-free survival (RFS). Hazard ratios (HRs) and 95% confidence intervals (CIs) were extracted and pooled with Mantel-Haenszel random-effect modeling. All statistical tests were two-sided.
  
  
  RESULTS
  Four studies on post-diagnosis statin therapy and five studies on pre-diagnosis statin use were included in our meta-analysis of 70,608 patients. Compared with the non-users, the patients with post-diagnosis statin use gained survival benefits for OS (HR 0.76; 95% CI: 0.68 to 0.85, P<0.001) and CSS (HR 0.70; 95% CI: 0.60 to 0.81, P<0.001). In addition, we observed that pre-diagnosis statin use prolonged the survival of patients with CRC for OS (HR 0.70; 95% CI: 0.54 to 0.91, P=0.007) and CSS (HR 0.80; 95% CI: 0.74 to 0.86, P<0.001). However, we did not observe a survival benefit for DFS (HR 1.13; 95% CI: 0.78 to 1.62, P=0.514) or RFS (HR 0.98; 95% CI: 0.36 to 2.70, P=0.975) in the CRC patients with post-diagnosis statin use.
  
  
  CONCLUSIONS
  Statin use before or after cancer diagnosis is related to reductions in overall and cancer-specific mortality in colorectal cancer survivors.
authors.affiliation: Department of Pharmacy, Anhui Provincial Children's Hospital, Hefei, Anhui Province, China.
authors.forename: Heping
authors.initials: H
authors.lastname: Cai
authors.affiliation: Department of Pharmacy, Anhui Provincial Children's Hospital, Hefei, Anhui Province, China.
authors.forename: Gongwu
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Department of Pharmacy, Changhai Hospital, Second Military Medical University, Shanghai, China.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Pharmacy, Anhui Provincial Children's Hospital, Hefei, Anhui Province, China.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Luo
authors.affiliation: Department of General Surgery, Lianyungang Oriental Hospital, Lianyun District, Lianyungang City, Jiangsu Province, China.
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Zhou
mesh_terms: D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000188:drug therapy*; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D017594:Publication Bias; D016019:Survival Analysis
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors