Trends in antiretroviral treatment use and treatment response in three Australian states in the first decade of combination antiretroviral treatment

Abstract

Objectives: To determine if there were any differences in antiretroviral treatment (ART) use across the three eastern states of Australia, New South Wales (NSW), Victoria and Queensland, during the period 1997 to 2006.

Methods: We used data from a clinic-based cohort, the Australian HIV Observational Database (AHOD), to determine the proportion of HIV-infected patients on ART in selected clinics in each state and the proportion of treated patients with an undetectable viral load. Data from the national Highly Specialised Drugs program and AHOD were used to estimate total numbers of individuals on ART and the proportion of individuals living with HIV on ART nationally and by state. Data from the HIV Futures Survey and the Gay Community Periodic Survey were used to determine the proportion of community-based men who have sex with men on ART. The proportion of patients with primary HIV infection (PHI) who commenced ART within 1 year of diagnosis was obtained from the Acute Infection and Early Disease Research Program (AIEDRP) CORE01 protocol and Primary HIV and Early Disease Research: Australian Cohort (PHAEDRA) cohorts.

Results: We estimated that the numbers of individuals on ART increased from 3181 to 4553 in NSW, 1309 to 1926 in Victoria and 809 to 1615 in Queensland between 2000 and 2006. However, these numbers may reflect a lower proportion of individuals living with HIV on ART in NSW compared with the other states (37% compared with 49 and 55% in 2000). We found similar proportions of HIV-positive men who have sex with men participants were on ART in all three states over the study period in the clinic-based AHOD cohort (81-92%) and two large, community-based surveys in Australia (69-85% and 49-83%). Similar proportions of treated patients had an undetectable viral load across the three states, with a consistently increasing trend over time observed in all states. We found that more PHI patients commenced treatment in the first year following HIV diagnosis in NSW compared with Victoria; however, the sample size was very small.

Conclusions: For the most part, patterns of ART use were similar across NSW, Victoria and Queensland using a range of available data from cohort studies, community surveys and national prescription databases in Australia. However, there may be a lower proportion of individuals living with HIV on ART in NSW compared with the other states, and there is some indication of a more aggressive treatment approach with PHI patients in NSW compared with Victoria.

Figures

FIGURE 1. Antiretroviral treatment (ART) use (%) among patients under follow up in AHOD* by year and state.

*Only patients with male homosexual contact reported as their HIV exposure. Legend: Open circles = NSW, closed squares = Victoria and closed triangles = Queensland.

FIGURE 2. Undetectable viral load (%) among patients in AHOD* by antiretroviral treatment (ART) status, year and state.

*Only patients with male homosexual contact reported as their HIV exposure. Legend: Open circles = NSW patients on ART, closed circles = NSW patients off ART, closed squares = Victorian patients on ART, open squares = Victorian patients off ART, closed triangles = Queensland patients on ART and open triangles = Queensland patients off ART.

Figure 3. Estimated percentage of individuals living with HIV on antiretroviral treatment (ART) annually in Australia and by state

Legend: Open circles = NSW, closed squares = Victoria and closed triangles = Queensland, crosses = Australia.

Figure 4. Treatment status of patients recruited to the primary HIV infection cohorts

Legend: Black represents patients who commenced ART within one year of their first positive ELISA test; diagonal lines represent patients who commenced ART more than one year after their first positive ELISA test; and white represents patients who have not commenced ART.

Figure 5. Self reported current antiretroviral treatment (ART) use (%) among participants in the HIV Futures Survey* by state and year.

*Only patients reporting male homosexual contact. Legend: Open circles = NSW, closed squares = Victoria and closed triangles = Queensland.

Figure 6. Self reported combination antiretroviral treatment (ART) use (%) among participants in the Gay Community Periodic Survey by state and year.

*Only patients reporting male homosexual contact. Legend: Open circles = NSW, closed squares = Victoria and closed triangles = Queensland.