title: Health care services utilization stratified by virological and immunological markers of HIV: evidence from a universal health care setting.
abstract: OBJECTIVE
  The aim of the study was to determine rates of utilization of in-patient, out-patient and laboratory services stratified by virological and immunological markers of HIV disease among patients on antiretroviral treatment in British Columbia, Canada.
  
  
  METHODS
  We estimated resource utilization for in-patient visits, out-patient visits, and laboratory tests among patients initiating antiretroviral treatment between 1 April 1994 and 31 December 2000, with follow-up to 31 March 2001. Resource use was stratified by CD4 cell count and plasma HIV viral load (pVL) at the time of utilization and rates per 100 patient-years were calculated for each health care resource.
  
  
  RESULTS
  A total of 2718 patients were included in our analyses. The overall rates of in-patient visits, out-patient visits, and laboratory tests were 902, 3001 and 840 per 100 patient-years, respectively. Utilization was higher for patients with low CD4 cell counts and high pVLs when compared with patients with high CD4 cell counts and low pVLs.
  
  
  CONCLUSIONS
  Patients with low CD4 cell counts and high pVLs had the highest use of health care services. Regular follow-up with health care providers in an out-patient setting, allowing for proper monitoring and maintenance of HIV care, is important in minimizing unnecessary and potentially costly in-patient care.
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, St Paul's Hospital, Vancouver, Canada.
authors.forename: E F
authors.initials: EF
authors.lastname: Druyts
authors.forename: B
authors.initials: B
authors.lastname: Yip
authors.forename: V D
authors.initials: VD
authors.lastname: Lima
authors.forename: T A
authors.initials: TA
authors.lastname: Burke
authors.forename: D
authors.initials: D
authors.lastname: Lesovski
authors.forename: K A
authors.initials: KA
authors.lastname: Fernandes
authors.forename: C W
authors.initials: CW
authors.lastname: McInnes
authors.forename: C A
authors.initials: CA
authors.lastname: Rustad
authors.forename: J S G
authors.initials: JS
authors.lastname: Montaner
authors.forename: R S
authors.initials: RS
authors.lastname: Hogg
mesh_terms: D000328:Adult; D023241:Antiretroviral Therapy, Highly Active / Q000706:statistics & numerical data*; D001955:British Columbia / Q000453:epidemiology; D018791:CD4 Lymphocyte Count; D005260:Female; D015658:HIV Infections / Q000453:epidemiology* / Q000276:immunology / Q000821:virology; D015497:HIV-1; D006297:Health Services Accessibility / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data*; D055815:Young Adult