Early initiation of antiretroviral therapy for people newly diagnosed with HIV infection in Australia: trends and predictors, 2004–2015

OBJECTIVES: To determine trends in and predictors of early treatment for people newly diagnosed with human immunodeficiency virus (HIV) infection in Australia. DESIGN, SETTING: Retrospective cohort analysis of routinely collected longitudinal data from 44 sexual health clinics participating in the Australian Collaboration for Coordinated Enhanced Sentinel Surveillance (ACCESS) program. PARTICIPANTS: Patients diagnosed with HIV infections, January 2004 - June 2015. MAIN OUTCOME MEASURES: Commencement of antiretroviral therapy within 6 months of HIV diagnosis (early treatment); demographic, clinical, and risk group characteristics of patients associated with early treatment; trends in early treatment, by CD4+ cell count at diagnosis. RESULTS: 917 people were diagnosed with HIV infections, their median age was 34 years (interquartile range [IQR]: 27-43 years), and 841 (92%) were men; the median CD4+ cell count at diagnosis was 510 cells/μL (IQR, 350-674 cells/μL). The proportion of patients who received early treatment increased from 17% (15 patients) in 2004-06 to 20% (34 patients) in 2007-09, 34% (95 patients) in 2010-12, and 53% (197 patients) in 2013-15 (trend, P < 0.001). The probability of early treatment, which increased with time, was higher for patients with lower CD4+ cell counts and higher viral loads at diagnosis. CONCLUSIONS: The proportion of people newly diagnosed with HIV in sexual health clinics in Australia who received treatment within 6 months of diagnosis increased from 17% to 53% during 2004-2015, reflecting changes in the CD4+ cell count threshold in treatment guidelines. Nevertheless, further strategies are needed to maximise the benefits of treatment to prevent viral transmission and morbidity.