title: Long term antihypertensive drug use and prostate cancer risk: A 9-year population-based cohort analysis.
abstract: BACKGROUND
  Recent findings from clinical trials have indicated inconsistent associations between angiotensin II receptor blockers and the risk of cancer incidence. Furthermore, the relationship between antihypertensive drugs and prostate cancer in hypertensive patients remains unclear.
  
  
  METHODS
  From Taiwan's national health insurance database, we identified 80,299 patients diagnosed with hypertension in 2001 and matched with 321,916 subjects without hypertension by age, income, urbanization level, and index day. A total of 684 hypertensive patients without antihypertensive drug use (drug non-user subcohort) were also matched (1:4) with 2736 patients on antihypertensive medication (drug subcohort) using the same criteria. Each subject in the two study groups was followed up for a maximum of nine years, during which death was considered a competing event when performing the stratified Fine and Gray regression hazards model for the estimation of prostate cancer risk for the cohorts. Uptake of antihypertensive prescription was considered a time-dependent variable.
  
  
  RESULTS
  Our findings indicate that patients with hypertension are at significantly increased risk for prostate cancer incidence when compared to their matched non-hypertensive counterparts (sHR=6.80, 95% CI=1.97-23.44, p=0.0024). Among hypertensive patients, those with long term antihypertensive drug use are not at elevated risk of developing prostate cancer relative to non-users of antihypertensive drugs (1-5 year vs. non-user sHR=0.99, 95% CI=0.32-3.05; >5 year vs. non-user sHR=0.88, 95% CI=0.34-2.26).
  
  
  CONCLUSIONS
  Hypertension is considered a risk factor for prostate cancer. However, long term uptake of antihypertensive medication in male hypertensive patients should not be a concern for the development of prostate cancer.
authors.affiliation: Division of General Medicine, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan; Division of Cardiovascular Medicine, Department of Internal Medicine, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Pei-Ying
authors.initials: PY
authors.lastname: Pai
authors.affiliation: Department of Health Services Administration, China Medical University, Taichung, Taiwan.
authors.forename: Vivian Chia-Rong
authors.initials: VC
authors.lastname: Hsieh
authors.affiliation: Graduate Institute of Public Health, China Medical University, Taichung, Taiwan.
authors.forename: Chang-Bi
authors.initials: CB
authors.lastname: Wang
authors.affiliation: Department of Urology, China Medical University Hospital, Taichung, Taiwan; School of Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Hsi-Chin
authors.initials: HC
authors.lastname: Wu
authors.affiliation: Graduate Institute of Biostatistics, China Medical University, Taichung, Taiwan; Biostatistics Center, China Medical University, Taichung, Taiwan.
authors.forename: Wen-Miin
authors.initials: WM
authors.lastname: Liang
authors.affiliation: Graduate Institute of Public Health, China Medical University, Taichung, Taiwan; Epidemiology and Biostatistics Center, Changhua Christian Hospital, Changhua, Taiwan.
authors.forename: Yu-Jun
authors.initials: YJ
authors.lastname: Chang
authors.affiliation: Department of Nursing, College of Medicine and Nursing, Hungkuang University, Taichung, Taiwan. Electronic address: tnwu@sunrise.hk.edu.tw.
authors.forename: Trong-Neng
authors.initials: TN
authors.lastname: Wu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000009:adverse effects* / Q000627:therapeutic use; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000209:etiology; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology; D013997:Time Factors
chemical_list: D000959:Antihypertensive Agents
keywords: Antihypertensive drugs; Hypertension; Prostate cancer