title: Health Canada Warning on Citalopram and Escitalopram--Its Effects on Prescribing in Consultation-Liaison Psychiatry.
abstract: BACKGROUND
  Reports have suggested that citalopram and escitalopram may prolong the QTc interval, leading Health Canada to issue a warning to limit their dosages in 2012. Little is known about the effects of this warning and similar ones (e.g., by the Food and Drug Administration) on antidepressant prescribing in inpatients with acute medical illness, who are theoretically at high risk of QTc prolongation. The main objective of our study is to examine the effect of the Health Canada warning on citalopram/escitalopram prescribing patterns in the consultation-liaison (C-L) psychiatry setting.
  
  
  METHODS
  We performed a retrospective cohort study including 275 randomly selected inpatients with medical illness assessed by the psychiatric C-L team of a large Canadian academic hospital between 2008 and 2014. We grouped patients based on whether they were assessed by the C-L team before or after the citalopram Health Canada warning. Our primary outcome was change in citalopram/escitalopram prescribing patterns.
  
  
  RESULTS
  We found that of patients seen before the Health Canada warning, a significantly higher number were prescribed citalopram/escitalopram (44.1% vs. 22.3%, χ(2) = 14.835, p < 0.001), even after controlling for confounders. However, the percentage of patients using a citalopram/escitalopram dose exceeding those recommended by the Health Canada warning was similar in both groups (8.9% vs. 12.1%, χ(2) = 0.233, p = 0.63).
  
  
  CONCLUSIONS
  Overall, C-L psychiatrists were less likely to prescribe citalopram/escitalopram following the Health Canada warning, which did not translate into safer dosing. Clinicians should not avoid prescribing citalopram/escitalopram appropriately in medically vulnerable inpatients when benefits outweigh disadvantages.
authors.affiliation: Geri-PARTy Research Group, Department of Psychiatry, Jewish General Hospital, McGill University, Montreal, Canada.
authors.forename: André
authors.initials: A
authors.lastname: Do
authors.affiliation: Geri-PARTy Research Group, Department of Psychiatry, Jewish General Hospital, McGill University, Montreal, Canada.
authors.forename: Saeid
authors.initials: S
authors.lastname: Noohi
authors.affiliation: Geri-PARTy Research Group, Department of Psychiatry, Jewish General Hospital, McGill University, Montreal, Canada.
authors.forename: Dominique
authors.initials: D
authors.lastname: Elie
authors.affiliation: Geri-PARTy Research Group, Department of Psychiatry, Jewish General Hospital, McGill University, Montreal, Canada.
authors.forename: Artin A
authors.initials: AA
authors.lastname: Mahdanian
authors.affiliation: Geri-PARTy Research Group, Department of Psychiatry, Jewish General Hospital, McGill University, Montreal, Canada.
authors.forename: Ching
authors.initials: C
authors.lastname: Yu
authors.affiliation: Geri-PARTy Research Group, Department of Psychiatry, Jewish General Hospital, McGill University, Montreal, Canada.
authors.forename: Marilyn
authors.initials: M
authors.lastname: Segal
authors.affiliation: Geri-PARTy Research Group, Department of Psychiatry, Jewish General Hospital, McGill University, Montreal, Canada.
authors.forename: Karl J
authors.initials: KJ
authors.lastname: Looper
authors.affiliation: Geri-PARTy Research Group, Department of Psychiatry, Jewish General Hospital, McGill University, Montreal, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada. Electronic address: soham.rej@mail.mcgill.ca.
authors.forename: Soham
authors.initials: S
authors.lastname: Rej
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018687:Antidepressive Agents, Second-Generation / Q000008:administration & dosage / Q000009:adverse effects*; D001145:Arrhythmias, Cardiac / Q000139:chemically induced*; D002170:Canada; D015283:Citalopram / Q000008:administration & dosage / Q000009:adverse effects*; D015331:Cohort Studies; D004348:Drug Labeling; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D011570:Psychiatry; D012017:Referral and Consultation; D012189:Retrospective Studies
chemical_list: D018687:Antidepressive Agents, Second-Generation; D015283:Citalopram