title: Treatment patterns of venous thromboembolism in a real-world population: the Q-VTE study cohort.
abstract: BACKGROUND
  Few studies have assessed treatment patterns of acute venous thromboembolism (VTE) in a real-world population. We aimed to describe anticoagulant treatment patterns for acute VTE using healthcare databases of Québec, Canada.
  
  
  METHODS
  We used linked healthcare databases of the province of Québec, Canada to identify all incident cases of deep vein thrombosis (DVT) and pulmonary embolism (PE) between 2000 and 2009. We formed two patient cohorts, one with definite cases (definite VTE cohort, N=40,776) and the other including cases with definite or probable VTE (any VTE cohort, N=54,803) that were followed until death, end of health coverage, or end of study (December 31, 2009).
  
  
  RESULTS
  In the definite cohort, 73.6% of subjects were dispensed an anticoagulant following the diagnosis of VTE. Of those who were dispensed a vitamin K antagonist (VKA), median duration of use was 61days (interquartile range 89). VKA initiation was more likely in patients with pulmonary embolism than deep vein thrombosis alone (HR 1.62, 95% CI (1.58-1.66)). Among outpatients, those managed initially in the outpatient setting were less likely to initiate VKA therapy (HR 0.75, 95% CI (0.68-0.77)), while those requiring admission to hospital for VTE management were more likely to initiate (HR 1.81, 95% CI (1.76-1.87)). Findings were similar in the any VTE cohort.
  
  
  CONCLUSIONS
  Our study describes VTE treatment patterns in a real-world setting and suggests that there may be important gaps. These may include significant numbers of patients who did not initiate oral anticoagulant therapy, particularly in the outpatient setting, and shorter duration of oral anticoagulant use than recommended.
authors.affiliation: Centre for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada. Electronic address: vicky.tagalakis@mcgill.ca.
authors.forename: Vicky
authors.initials: V
authors.lastname: Tagalakis
authors.affiliation: Centre for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada.
authors.forename: Valérie
authors.initials: V
authors.lastname: Patenaude
authors.affiliation: Centre for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada.
authors.forename: Susan R
authors.initials: SR
authors.lastname: Kahn
authors.affiliation: Centre for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada; Department of Epidemiology and Biostatistics, McGill University, Montréal, Québec, Canada.
authors.forename: Samy
authors.initials: S
authors.lastname: Suissa
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D011655:Pulmonary Embolism / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology; D011792:Quebec / Q000453:epidemiology; D054556:Venous Thromboembolism / Q000150:complications / Q000188:drug therapy* / Q000453:epidemiology; D014812:Vitamin K / Q000037:antagonists & inhibitors*; D055815:Young Adult
chemical_list: D000925:Anticoagulants; D014812:Vitamin K
keywords: Anticoagulants; Deep vein thrombosis; Pulmonary embolism; Treatment patterns; Venous thromboembolism