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PharmacoEconomics

, Volume 33, Issue 3, pp 243–253 | Cite as

Costs of Health Resource Utilization Among HIV-Positive Individuals in British Columbia, Canada: Results From a Population-Level Study

  • Bohdan Nosyk
  • Viviane Lima
  • Guillaume Colley
  • Benita Yip
  • Robert S. Hogg
  • Julio S. G. Montaner
Original Research Article

Abstract

Background

Through delayed HIV disease progression, highly active antiretroviral therapy (HAART) may reduce direct medical costs, thus at least partially offsetting therapy costs. Recent findings regarding the secondary preventive benefits of HAART necessitate careful consideration of funding allocations for HIV/AIDS care. Our objective is to estimate non-HAART direct medical costs at different levels of disease progression and over time in British Columbia, Canada.

Methods

We considered the population of individuals with HIV/AIDS within a set of linked disease registries and health administrative databases (N = 11,836) from 1996 to 2010. Costs of hospitalization, physician billing, diagnostic testing and non-HAART medications were calculated in 2010 Canadian dollars. Effects of covariates on quarterly costs were assessed with a two-part model with logit for probability of non-zero costs and a generalized linear model (GLM). Net effects of CD4 strata on direct non-HAART medical costs were evaluated over time during the study period.

Results

Compared with person-quarters in which CD4 >500/mm3, costs were Can$185 (95 % confidence interval [CI] 132–239) greater for CD4 350–500/mm3, Can$441 (95 % CI 366–516) greater for CD4 200–350/mm3 and Can$1,173 (95 % CI 1,051–1,294) greater when CD4 <200/mm3. Prior to HIV care initiation, individuals incurred costs Can$385 (95 % CI 283–487) greater than in periods with CD4 >500/mm3. Hospitalization comprised the majority of the increment in costs amongst those with no measured CD4. Evaluated at CD4 state conditional means, those with CD4 <200/mm3 incurred quarterly costs of Can$5,781 (95 % CI 4,716–6,846) versus Can$1,307 (95 % CI 1,154–1,460; p < 0.001) for CD4 ≥500/mm3 in 2010.

Conclusion

Non-HAART direct medical costs were substantially lower for individuals during periods of sustained virologic suppression and high CD4 count. HIV treatment and prevention evaluations require detailed health resource use data to inform funding allocation decisions.

Keywords

British Columbia Health Resource Utilization Physician Billing Medical Service Plan Sustained Virologic Suppression 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

We acknowledge Dr. Jean Nachega for methodological guidance as well as all BC Ministry of Health and Vancouver Coastal Health Decision Support Staff involved in data access and procurement, including Monika Lindegger, Clinical Prevention Services, BC Centre for Disease Control; Elsie Wong, Public Health Agency of Canada; Al Cassidy, BC Ministry of Health Registries and Joleen Wright and Karen Luers, Vancouver Coastal Health decision support. This study was funded by the BC Ministry of Health-funded ‘Seek and treat for optimal prevention of HIV & AIDS’ pilot project. Bohdan Nosyk and Viviane Lima are Michael Smith Foundation for Health Research scholars, and Viviane Lima also holds a CIHR New Investigator award.

Funding

This study was funded by the BC Ministry of Health, as well as through an Avant-Garde Award (No. 1DP1DA026182) from the National Institute of Drug Abuse, at the US National Institutes of Health.

Conflicts of interest

Dr. Julio Montaner has received grants from Abbott, Biolytical, Boehringer Ingelheim, Bristol-Myers Squibb, Gilead Sciences, Janssen, Merck and ViiV Healthcare. He is also is supported by the Ministry of Health Services and the Ministry of Healthy Living and Sport, from the Province of British Columbia; through a Knowledge Translation Award from the Canadian Institutes of Health Research (CIHR); and through an Avant-Garde Award (No. 1DP1DA026182) from the National Institute of Drug Abuse, at the US National Institutes of Health. He has also received support from the International AIDS Society, United Nations AIDS Program, World Health Organization, National Institute on Drug Abuse, National Institutes of Health Research–Office of AIDS Research, National Institute of Allergy & Infectious Diseases, The United States President’s Emergency Plan for AIDS Relief (PEPfAR), Bill & Melinda Gates Foundation, French National Agency for Research on AIDS & Viral Hepatitis (ANRS), Public Health Agency of Canada. All other authors have no conflicts of interest to declare.

Authors’ Contributions

BN conceived the study design, led the econometric analysis and wrote the first draft of the article. VDL, BY and GC all contributed to the analysis. RSH and JSGM contributed to the study design and secured access to the data. All authors provided critical reviews and ultimately approved the submitted draft of the manuscript. BN had full access to the data and is the guarantor for the overall content of the manuscript.

Supplementary material

40273_2014_229_MOESM1_ESM.docx (38 kb)
Supplementary material 1 (DOCX 38 kb)

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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Bohdan Nosyk
    • 1
    • 2
  • Viviane Lima
    • 1
    • 3
  • Guillaume Colley
    • 1
  • Benita Yip
    • 1
  • Robert S. Hogg
    • 1
    • 2
  • Julio S. G. Montaner
    • 1
    • 3
  1. 1.BC Centre for Excellence in HIV/AIDS, St. Paul’s Hospital, Providence HealthcareVancouverCanada
  2. 2.Faculty of Health SciencesSimon Fraser UniversityVancouverCanada
  3. 3.Division of AIDS, Department of MedicineUniversity of British ColumbiaVancouverCanada

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