title: Angiotensin receptor blockers and risk of cancer: cohort study among people receiving antihypertensive drugs in UK General Practice Research Database.
abstract: OBJECTIVE
  To investigate whether there is an association between use of angiotensin receptor blockers and risk of cancer.
  
  
  METHODS
  Cohort study of risk of cancer in people treated with angiotensin receptor blockers compared with angiotensin converting enzyme (ACE) inhibitors. Effects were explored with time updated covariates in Cox models adjusted for age, sex, body mass index (BMI), diabetes and metformin/insulin use, hypertension, heart failure, statin use, socioeconomic status, alcohol, smoking, and calendar year. Absolute changes in risk were predicted from a Poisson model incorporating the strongest determinants of risk from the main analysis.
  
  
  METHODS
  UK primary care practices contributing to the General Practice Research Database.
  
  
  METHODS
  377,649 new users of angiotensin receptor blockers or ACE inhibitors with at least one year of initial treatment.
  
  
  METHODS
  Adjusted hazard ratios for all cancer and major site specific cancers (breast, lung, colon, prostate) by exposure to angiotensin receptor blockers and by cumulative duration of use.
  
  
  RESULTS
  Follow-up ended a median of 4.6 years after the start of treatment; 20,203 cancers were observed. There was no evidence of any increase in overall risk of cancer among those ever exposed to angiotensin receptor blockers (adjusted hazard ratio 1.03, 95% confidence interval 0.99 to 1.06, P = 0.10). For specific cancers, there was some evidence of an increased risk of breast and prostate cancer (1.11, 1.01 to 1.21, P = 0.02; and 1.10, 1.00 to 1.20, P = 0.04; respectively), which in absolute terms corresponded to an estimated 0.5 and 1.1 extra cases, respectively, per 1000 person years of follow-up among those with the highest baseline risk. Longer duration of treatment did not seem to be associated with higher risk (P>0.15 in each case). There was a decreased risk of lung cancer (0.84, 0.75 to 0.94), but no effect on colon cancer (1.02, 0.91 to 1.16).
  
  
  CONCLUSIONS
  Use of angiotensin receptor blockers was not associated with an increased risk of cancer overall. Observed increased risks for breast and prostate cancer were small in absolute terms, and the lack of association with duration of treatment meant that non-causal explanations could not be excluded.
authors.affiliation: Department of Non-Communicable Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK. krishnan.bhaskaran@lshtm.ac.uk
authors.forename: Krishnan
authors.initials: K
authors.lastname: Bhaskaran
authors.forename: Ian
authors.initials: I
authors.lastname: Douglas
authors.forename: Stephen
authors.initials: S
authors.lastname: Evans
authors.forename: Tjeerd
authors.initials: T
authors.lastname: van Staa
authors.forename: Liam
authors.initials: L
authors.lastname: Smeeth
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D057911:Angiotensin Receptor Antagonists / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000453:epidemiology; D015984:Causality; D015331:Cohort Studies; D003627:Data Interpretation, Statistical; D005194:Family Practice / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D016347:Medical Records Systems, Computerized / Q000706:statistics & numerical data; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology*; D016016:Proportional Hazards Models; D011471:Prostatic Neoplasms / Q000453:epidemiology; D012307:Risk Factors; D006113:United Kingdom / Q000453:epidemiology; D055815:Young Adult
chemical_list: D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents