title: Life expectancy of HIV-positive individuals on combination antiretroviral therapy in Canada.
abstract: BACKGROUND
  We sought to evaluate life expectancy and mortality of HIV-positive individuals initiating combination antiretroviral therapy (ART) across Canada, and to consider the potential error introduced by participant loss to follow-up (LTFU).
  
  
  METHODS
  Our study used data from the Canadian Observational Cohort (CANOC) collaboration, including HIV-positive individuals aged ≥18 years who initiated ART on or after January 1, 2000. The CANOC collaboration collates data from eight sites in British Columbia, Ontario, and Quebec. We computed abridged life-tables and remaining life expectancies at age 20 and compared outcomes by calendar period and patient characteristics at treatment initiation. To correct for potential underreporting of mortality due to participant LTFU, we conservatively estimated 30% mortality among participants lost to follow-up.
  
  
  RESULTS
  9997 individuals contributed 49,589 person-years and 830 deaths for a crude mortality rate of 16.7 [standard error (SE) 0.6] per 1000 person-years. When assigning death to 30% of participants lost to follow-up, we estimated 1170 deaths and a mortality rate of 23.6 [SE 0.7] per 1000 person-years. The crude overall life expectancy at age 20 was 45.2 [SE 0.7] and 37.5 [SE 0.6] years after adjusting for LTFU. In the LTFU-adjusted analysis, lower life expectancy at age 20 was observed for women compared to men (32.4 [SE 1.1] vs. 39.2 [SE 0.7] years), for participants with injection drug use (IDU) history compared to those without IDU history (23.9 [SE 1.0] vs. 52.3 [SE 0.8] years), for participants reporting Aboriginal ancestry compared to those with no Aboriginal ancestry (17.7 [SE 1.5] vs. 51.2 [SE 1.0] years), and for participants with CD4 count <350 cells/μL compared to CD4 count ≥350 cells/μL at treatment initiation (36.3 [SE 0.7] vs. 43.5 [SE 1.3] years). Life expectancy at age 20 in the calendar period 2000-2003 was lower than in periods 2004-2007 and 2008-2012 in the LTFU-adjusted analyses (30.8 [SE 0.9] vs. 38.6 [SE 1.0] and 54.2 [SE 1.4]).
  
  
  CONCLUSIONS
  Life expectancy and mortality for HIV-positive individuals receiving ART differ by calendar period and patient characteristics at treatment initiation. Failure to consider LTFU may result in underestimation of mortality rates and overestimation of life expectancy.
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, Canada. sophie_patterson@sfu.ca.|Faculty of Health Sciences, BLU 9512, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6, Canada. sophie_patterson@sfu.ca.
authors.forename: Sophie
authors.initials: S
authors.lastname: Patterson
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, Canada. angela.cescon@gmail.com.|Northern Ontario School of Medicine, Sudbury, Ontario, Canada. angela.cescon@gmail.com.
authors.forename: Angela
authors.initials: A
authors.lastname: Cescon
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, Canada. hsamji@cfenet.ubc.ca.
authors.forename: Hasina
authors.initials: H
authors.lastname: Samji
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, Canada. keithjchan@gmail.com.
authors.forename: Keith
authors.initials: K
authors.lastname: Chan
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, Canada. wzhang@cfenet.ubc.ca.
authors.forename: Wendy
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Dalla Lana School of Public Health, University of Toronto, Toronto, Canada. janet@raboud.net.|Division of Infectious Diseases, University Health Network, Toronto, Canada. janet@raboud.net.
authors.forename: Janet
authors.initials: J
authors.lastname: Raboud
authors.affiliation: Ontario HIV Treatment Network, Toronto, Canada. aburchell@ohtn.on.ca.
authors.forename: Ann N
authors.initials: AN
authors.lastname: Burchell
authors.affiliation: The Ottawa Hospital Division of Infectious Diseases, University of Ottawa, Ottawa, Canada. ccooper@ottawahospital.on.ca.
authors.forename: Curtis
authors.initials: C
authors.lastname: Cooper
authors.affiliation: Faculty of Medicine, McGill University, Montreal, Canada. marina.klein@mcgill.ca.|The Montreal Chest Institute, McGill University Health Centre, Montreal, Canada. marina.klein@mcgill.ca.
authors.forename: Marina B
authors.initials: MB
authors.lastname: Klein
authors.affiliation: Ontario HIV Treatment Network, Toronto, Canada. sean.rourke@utoronto.ca.
authors.forename: Sean B
authors.initials: SB
authors.lastname: Rourke
authors.affiliation: Faculty of Medicine, University of Toronto, Toronto, Canada. mona.loutfy@wchospital.ca.|Maple Leaf Medical Clinic, Toronto, Canada. mona.loutfy@wchospital.ca.|Women's College Research Institute, Toronto, Canada. mona.loutfy@wchospital.ca.
authors.forename: Mona R
authors.initials: MR
authors.lastname: Loutfy
authors.affiliation: Clinique Medicale l'Actuel, Montreal, Canada. nmachouf@lactuel.ca.
authors.forename: Nima
authors.initials: N
authors.lastname: Machouf
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, Canada. jmontaner@cfenet.ubc.ca.|Faculty of Medicine, University of British Columbia, Vancouver, Canada. jmontaner@cfenet.ubc.ca.
authors.forename: Julio S G
authors.initials: JS
authors.lastname: Montaner
authors.affiliation: Faculty of Medicine, McGill University, Montreal, Canada. chris.tsoukas@muhc.mcgill.ca.
authors.forename: Chris
authors.initials: C
authors.lastname: Tsoukas
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, Canada. robert_hogg@sfu.ca.|Faculty of Health Sciences, BLU 9512, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6, Canada. robert_hogg@sfu.ca.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Hogg
mesh_terms: D000293:Adolescent; D000328:Adult; D044966:Anti-Retroviral Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001955:British Columbia / Q000453:epidemiology; D002170:Canada / Q000453:epidemiology; D004359:Drug Therapy, Combination; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000453:epidemiology*; D006679:HIV Seropositivity / Q000188:drug therapy / Q000453:epidemiology; D015497:HIV-1; D006801:Humans; D008017:Life Expectancy; D059012:Lost to Follow-Up; D008297:Male; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D011792:Quebec / Q000453:epidemiology; D055815:Young Adult
chemical_list: D044966:Anti-Retroviral Agents