title: Benzodiazepine Use and Risk of Developing Alzheimer's Disease or Vascular Dementia: A Case-Control Analysis.
abstract: BACKGROUND
  Previous observational studies have associated benzodiazepine use with an increased risk of dementia. However, limitations in the study methods leave questions unanswered regarding the interpretation of the findings.
  
  
  METHODS
  A case-control analysis was conducted using data from the UK-based Clinical Practice Research Datalink (CPRD). A total of 26,459 patients aged ≥65 years with newly diagnosed Alzheimer's disease (AD) or vascular dementia (VaD) between 1998 and 2013 were identified and matched 1:1 to dementia-free controls on age, sex, calendar time, general practice, and number of years of recorded history. Adjusted odds ratios (aORs) were calculated with 95% confidence intervals (CIs) of developing AD or VaD in relation to previous benzodiazepine use, stratified by duration and benzodiazepine type.
  
  
  RESULTS
  The aOR (95% CI) of developing AD for those who started benzodiazepines <1 year before diagnosis was 2.20 (1.91-2.53), and fell to the null for those who started between 2 and <3 years before [aOR 0.99 (0.84-1.17)]. The aOR (95% CI) of developing VaD for those who started benzodiazepines <1 year before diagnosis was 3.30 (2.78-3.92), and fell close to the null for those who started between 3 and <4 years before [aOR 1.16 (0.96-1.40)]. After accounting for benzodiazepine use initiated during this prodromal phase, long-term use of benzodiazepines was not associated with an increased risk of developing AD [aOR 0.69 (0.57-0.85)] or VaD [aOR 1.11 (0.85-1.45)].
  
  
  CONCLUSIONS
  After taking a prodromal phase into consideration, benzodiazepine use was not associated with an increased risk of developing AD or VaD.
authors.affiliation: Basel Pharmacoepidemiology Unit, Division of Clinical Pharmacy and Epidemiology, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland.|Hospital Pharmacy, University Hospital Basel, Basel, Switzerland.
authors.forename: Patrick
authors.initials: P
authors.lastname: Imfeld
authors.affiliation: Basel Pharmacoepidemiology Unit, Division of Clinical Pharmacy and Epidemiology, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland.
authors.forename: Michael
authors.initials: M
authors.lastname: Bodmer
authors.affiliation: Boston Collaborative Drug Surveillance Program, Boston University School of Public Health, Lexington, MA, USA.
authors.forename: Susan S
authors.initials: SS
authors.lastname: Jick
authors.affiliation: Basel Pharmacoepidemiology Unit, Division of Clinical Pharmacy and Epidemiology, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland. christoph.meier@usb.ch.|Hospital Pharmacy, University Hospital Basel, Basel, Switzerland. christoph.meier@usb.ch.|Boston Collaborative Drug Surveillance Program, Boston University School of Public Health, Lexington, MA, USA. christoph.meier@usb.ch.
authors.forename: Christoph R
authors.initials: CR
authors.lastname: Meier
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000139:chemically induced*; D001569:Benzodiazepines / Q000009:adverse effects*; D016022:Case-Control Studies; D015140:Dementia, Vascular / Q000139:chemically induced*; D005260:Female; D006801:Humans; D008297:Male; D012307:Risk Factors
chemical_list: D001569:Benzodiazepines