HIV costs: individual and population perspectives

teaser

EJ Beck
MB BS BMedSci MSc
PhD DHMSA DIC
DLSHTM FAFPHM FFPHM
Coordinator and Director NPMS-HHC
Coordination and Analytic Centre
Chelsea & Westminster
Hospital Trust
London, UK
Honorary Consultant in Public Health Medicine
Public Health Laboratory Service
Colindale, UK
Associate Professor
Joint Departments of Epidemiology
Biostatistics and Occupational Health
McGill University
Specialist in Public Health
Direction de la Santé Publique de Montreal-Centre
Hôpital Géneral de Montréal
Montreal, Canada
E:[email protected]

The introduction of highly active antiretroviral therapy (HAART) into routine clinical practice has had a profound impact on disease progression in HIV-infected individuals, resulting in dramatic reductions in HIV-related morbidity and mortality.(1–7) Despite side-effects(8) and problems with resistance to antiretroviral therapy (ART),(9–11) increasing numbers of people with HIV are receiving treatment across the world.(12) Improved treatment, combined with the continued transmission of HIV, has resulted in increasing numbers of individuals living with HIV around the world.(13)

ART was first introduced into routine clinical practice in 1987. Although AZT monotherapy has limited effectiveness, it was a cost-effective intervention. (14) In subsequent years, other nucleoside reverse transcriptase inhibitors (NRTIs) were developed, as were the protease inhibitors (PIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs), all of which have been introduced into clinical practice. While treatment with dual therapy commenced in 1994/95, triple therapy was put on the therapeutic map in 1996, when the results of the first efficacy trials on 2NRTIs + 1PI became available. Subsequently, firstline combinations of 2NRTIs + 1NNRTI have become more popular, especially in Europe, but many central issues, such as which is the optimal starting drug combination and when it should be initiated, are yet to be resolved. The development and introduction of nucleotide reverse transcriptase inhibitors and fusion inhibitors has increased the therapeutic options available to practitioners still further, and new compounds from existing classes of drugs are also being produced.

Individual cost of HIV service provision
The cost of these drugs and their impact on health budgets have been longstanding topics of discussion, (14–16) but since 1996 the rising costs of HIV drugs have become an especially persistent concern.(17,18) In the UK, after the introduction of HAART in 1996, people with AIDS (CDC Stage C) continued to use hospital inpatient services most intensively.(19,20) However, their use of inpatient services decreased over time, while asymptomatic patients (CDC Stage A) and patients with symptomatic non-AIDS (CDC Stage B) used more outpatient services.

The cost of treating asymptomatic individuals and people with symptomatic non-AIDS has not changed substantially in the UK since 1996 (see Table 1a), though HAART has increased the annual costs for these patient groups when compared with the period before 1996.(15,16) The annual costs for treating AIDS patients in the UK have decreased by £2,000 (£1 ≈ €1.45) since 1996, which is in part due to a reduction in the use of inpatient facilities with an increased use of outpatient services. On the whole, increased expenditure on HAART has been offset by a decrease in inpatient-related costs, a phenomenon observed earlier in the epidemic,(6,15,21) as well as in other industrialised countries.(22) Drug costs may, however, increase further with the introduction of new classes of drugs and the increasing need for the use of salvage therapy or Mega-HAART.(23)

[[HPE08_table1_49]]

Based on the annual direct costs by stage of HIV infection and the average time HIV-infected people spent in respective stages of HIV infection while using health services,(1) the average nondiscounted lifetime costs(24) for treatment with 2NRTIs + 1NNRTI was £135,420 (range £59,973–184,030), compared with £181,613 (range £82,093 –240,119) for treatment and care with 2NRTIs + 2PIs.

Population costs of HIV service provision
The estimated number of HIV-infected individuals who used NHS services during the study period increased from 13,400 in 1996 to 17,981 in 1999 – a 25% increase over four years.(21,25,26) During the same time period, estimated annual direct population costs increased from £209m (£176m–£253m) to £266m (£226m–£321m; see Table 1b). As with any illness, HIV infection also generates indirect costs.(27) Estimates of indirect costs in 1999 varied between  £53m and £133m.(28) If a public sector perspective is adopted and disability-related unemployment payments are included, costs estimates ranged from 28% to 34% of total direct costs, assuming a 100% loss in production; if a 50% loss of production is assumed, indirect costs estimates ranged between 20% and 25% of direct costs. From a societal perspective, which excludes disability-related unemployment payments, indirect costs estimates varied between 22% and 27% of total direct costs, assuming a 100% loss of production, and between 13% and 16% of total direct costs when assuming a 50% loss of production (see Table 1c).(28)

As HAART is more cost-effective than dual or monotherapy(29,30) and the number of newly diagnosed HIV-infected people has continued to increase in England(11) and many other countries, the number of HIV-infected people needing to use medical services is also likely to continue to increase,(28) with a resultant requirement for additional resources to maintain or improve existing standards of care.(28)

Future implications
Changes in therapeutic and diagnostic interventions are likely to remain an important feature of the management of HIV infection, with potentially profound implications for the provision of HIV services. Therefore multicentre information systems are being set up in various countries to monitor prospectively the effectiveness, efficiency, equity and acceptability of HIV service provision.(31)

In the UK, the National Prospective Monitoring System on the use, cost and outcome of HIV service provision in UK hospitals–HIV Health Economics Collaboration (NPMS–HHC) arose from a need for reliable information about existing patterns of service use, costs and outcomes that could be used to improve local, regional and national services within budgetary constraints in pursuit of “value for money” and quality in service provision for people with HIV infection.(28,32) The need for such data has not diminished (Kinghorn: personal communication; 2003). Data collected include the use of services, drug treatment, severity of HIV infection when services are used,(33) occurrence of disease progression or death and the type of opportunistic illnesses,(6) the cost of service provision,(33 )and views on the acceptability of services provided by those who use these services.(34) Analyses and feedback occur at aggregate and clinic-specific levels.(32)

Similar surveillance systems have been established in France (DMI 2) and the Netherlands (Dutch HIV Monitoring Foundation), and are being established in Canada (RISQ and HIIP).(35–38) Unlike the UK system, the surveillance systems being developed in these countries are being financed through public funds.(32) All of these systems collect data in a standardised format prospectively in participating HIV clinics.

Given that most randomised controlled trials of new drugs or drug combinations currently use small sample populations, often utilising surrogate markers as endpoints, and therefore are of relatively short duration, and given the problems of sideeffects and viral resistance associated with the longterm use of HAART, observational databases are likely to become more and more important to assess the effectiveness and cost of these drugs, and their various combinations, within routine clinical settings.(18,31) Apart from being potentially useful for direct patient management, data collected through such schemes provide reliable and contemporary information on the impact of interventions at clinic level, as well as providing comparative information for policy formulation and evaluation at regional, national and international levels.

References

1. Beck EJ, Mandalia S, Parmar D, et al, for the NPMS-HHC Steering Group. Reduced HIV disease progression and mortality due to combination anti-retroviral therapy in English NPMS-HHC clinics. 13th International AIDS Conference, Durban, South Africa; 9–14 July 2000. Poster TuPeC3331.
2. Walsh JC, Jones CD, Barnes EA, et al. AIDS 1998;12:613-8.
3. Palella FJ, Delaney KM, Moorman AC, et al. N Engl J Med 1998;338:853-60.
4. Hammer SM, Katzenstein DA, Hughes MD, et al, for the AIDS Clinical Trial  Group Study 175 Study Team. N Engl J Med 1996;335:1081-90.
5. Autrran B, Carcelain G, Tubiana R, et al. Effects of antiretroviral therapy on immune reconstitution. 6th Conference on Retroviruses and Opportunistic Infections, Chicago, USA; 31 Jan–4 Feb 1999.Abs S44.
6. Beck EJ, Mandalia S, Williams I, et al, for the NPMS Steering Group. AIDS 1999;13:2157-64.
7. Hogg RS, Heath KA, Yip B et al. JAMA 1998;279:450-4.
8. Mandalia S, Parmar D, Fisher M, et al, on behalf of the NPMS-HHC Steering Group. HIV Med 2002;3:254-62.
9. Little SJ. BMJ 2001;322:1074-5.
10. UK Collaborative Group on Monitoring the Transmission of HIV Drug Resistance. BMJ 2001;322:1087-8.
11. Hirsch MS. N Engl J Med 2002;347:438-9.
12. HIV and STD Division, Communicable Disease Surveillance Centre. AIDS/HIV quarterly surveillance tables: cumulative UK data to the end March 2001. Colindale: PHLS AIDS Centre; 2001. Table 3a.
13. UNAIDS. Report on the global HIV/AIDS epidemic – 2002. Geneva: UNAIDS; 2002.
14. Beck EJ, Kupek EJ, Petrou S, et al. Int J STD AIDS 1996;7:507-12.
15. Beck EJ, Kennelly J, McKevitt C, et al. AIDS 1994;8:367-77.
16. Beck EJ, Whitaker L, Kennelly J, et al. AIDS 1994;8:379-84.
17. Curtis H. J HIV Comb Ther 1997;2:27-8.
18. Beck EJ. J HIV Comb Ther 1997;2:29-32.
19. PHLS AIDS Centre. AIDS Surveillance and HIV Death Clinical Report Form. London: PHLS, Communicable Disease Surveillance Centre; 1993.
20. Beck EJ, Mandalia S, Parmar D, et al, for the NPMS-HHC Steering Group. Use and cost of HIV service provision in English NPMS-HHC sites. Year 2001 report: aggregate analyses, January 1996 – December 2000. London: NPMS-HHC Coordinating and Analytic Centre; 2001.
21. Beck EJ, Pozniak A, Molesworth A, et al, for the NPMS Steering Group. Int J STD AIDS 1999;10:357-62.
22. Beck EJ, Miners AH, Tolley K. Pharmacoeconomics 2001;19:13-39.
23. Youle M. Int J STD & AIDS 2001;12:286-93
24. Parsonage M, Neuberger H. Health Econ 1992;1:71-6.
25. Neil Macdonald (Coordinator for the Survey of Prevalent Diagnosed HIV Infections, PHLS HIV and STI Centre), personal communications 2001: 1998 SOPHID data.
26. 1999 SOPHID data. Available from URL: http://www.phls.co.uk/facts/HIV/ HivSophidsummaries.ppt (accessed 4/6/2001).
27. Mullins CD, Whitelaw G, Cooke JL, Beck EJ. Clin Ther 2000;22:1333-45.
28. Beck EJ, Mandalia S. Br J Sex Med 2003; (in press).
29. Trueman P, Youle M, Sabin CA, et al. HIV Clinical Trials 2000;1:27-35.
30. Miners AH, Sabin CA, Trueman P, et al. HIV Medicine 2001;2:52-8.
31. Beck EJ, Miners AH. Effectiveness and efficiency in the delivery of HIV services: economic and related considerations. In: Gazzard B, Johnson M, Miles A, editors. The effective management of HIV disease. London: Aesculapius Medical Press; 2001. p.113-38.
32. Beck EJ, Mandalia S. The cost of HIV treatment and care in England since HAART: part 2. Br J Sex Med 2003; (in press).
33. Beck EJ, Tolley K, Power A, et al, for the NPMS Steering Group. Pharmacoeconomics 1998;14:639-52.
34. Beck EJ, Griffith R, Fitzpatrick R, et al. AIDS Care 1999;11:331-43.
35. Direction des Hospitaux, Mission SIDA. DMI2: an information system built around the patient. Paris, France: INSERM – SC4, Ministere de la Sante et de  ‘action Humanitaire; 1993.
36. De Wolf F, Lange JMA, Bossuyt PMM, et al, for the Athena Project. Monitoring of HIV- 1 infection in the Netherlands. Amsterdam: Stichting HIV Monitoring, Natec, AMC; 2001.
37. Beck EJ, P Robillard P, Coté P, et al. Réseau Informatique de Sida au Québec. Montreal, Canada: Unité Maladies Infectieuses, Direction de la santé publique, Regie Regionale de la Sante et Des Services Sociaux De Montreal-Centre; 2001.
38. Available from URL: http://www.ohtn. on.ca/hiipfacts.html (accessed 29/9/2001).