title: Lovastatin lowers the risk of breast cancer: a population-based study using logistic regression with a random effects model.
abstract: BACKGROUND
  Laboratory studies have demonstrated statin-induced apoptosis of cancer cells, including breast cancer cells, and evidence is accumulating on the mechanism of statin-induced apoptosis. However, despite numerous epidemiological studies, no consensus has been reached regarding the relationship between statin use and breast cancer risk.
  
  
  METHODS
  This retrospective case-control study enrolled 4332 breast cancer patients and 21,660 age-matched controls registered in the National Health Insurance program of Taiwan, which covers approximately 99% of the population. The study cases were women for whom a diagnosis of breast cancer (ICD-9-CM code 174.X) had been recorded in LHID2005 between January 1, 2004 and December 31, 2010. A logistic regression model was adjusted for potential confounding factors, including the level of urbanization, and the Charlson Comorbidity Index was applied to assess potential comorbidities. We also considered possible bias caused by random urbanization, because nutrition and lifestyle factors are related to breast cancer incidence.
  
  
  RESULTS
  Our results showed that lovastatin was associated with a lower risk of breast cancer (adjusted OR 0.596; 95% CI 0.497-0.714;p< 0.001), and atorvastatin exhibited a protective tendency against breast cancer (adjusted OR 0.887; 95% CI 0.776-1.013;p< 0.077).
  
  
  CONCLUSIONS
  Although no consensus has been established regarding the relationship between statin use and breast cancer risk, our study indicated that lovastatin is a potential chemopreventive agent against breast cancer. Further detailed research is warranted.
authors.affiliation: Department of Family Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.
authors.forename: Rimi
authors.initials: R
authors.lastname: Murakami
authors.affiliation: Division of Plastic Surgery, Department of Surgery, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.|Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.|Evidence-Based Medicine Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.|Cochrane Taiwan, Taipei Medical University, Taipei, Taiwan.
authors.forename: Chiehfeng
authors.initials: C
authors.lastname: Chen
authors.affiliation: School of Public Health, Taipei Medical University, Taipei, Taiwan.|Department of Leisure Industry and Health Promotion, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan.
authors.forename: Shu-Yu
authors.initials: SY
authors.lastname: Lyu
authors.affiliation: Department of Family Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.
authors.forename: Ching-En
authors.initials: CE
authors.lastname: Lin
authors.affiliation: Evidence-Based Medicine Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.
authors.forename: Pei-Chuan
authors.initials: PC
authors.lastname: Tzeng
authors.affiliation: Department of Family Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.
authors.forename: Tzu-Feng
authors.initials: TF
authors.lastname: Wang
authors.affiliation: Department of Family Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.
authors.forename: Juei-Chin
authors.initials: JC
authors.lastname: Chang
authors.affiliation: Department of Family Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.
authors.forename: Ying-Hua
authors.initials: YH
authors.lastname: Shieh
authors.affiliation: Graduate Institute of Management of Technology, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: I-Fan
authors.initials: IF
authors.lastname: Chen
authors.affiliation: Institute of Management of Technology, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Shihping Kevin
authors.initials: SK
authors.lastname: Huang
authors.affiliation: Evidence-Based Medicine Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.|Department of Mathematics, Soochow University, 70 Linhsi Road, Shihlin, Taipei, Taiwan.
authors.forename: Hui-Wen
authors.initials: HW
authors.lastname: Lin
keywords: Atorvastatin; Breast neoplasms; Fluvastatin; Lovastatin; Pravastatin; Simvastatin