What can viral suppression indicators tell us? Monitoring progress towards improvement in HIV care for those newly diagnosed in Queensland, Australia

Abstract

Background: Shortening the time to viral suppression after HIV diagnosis reduces morbidity and transmission. Current treatment commencement indicators do not include the more relevant clinical and public health outcome of viral suppression. With this study, we explored a recently proposed process indicator for HIV care quality, the percentage of newly diagnosed individuals achieving early viral suppression, and investigated risk factors for non-suppression in Queensland, Australia. Methods and materials: We constructed a retrospective cohort of Queensland state-wide surveillance data for newly diagnosed people with HIV, 2014–2018. Percentage of newly diagnosed people achieving viral suppression, viral load <200 copies/mL, within 3- and 6-months of diagnosis was calculated overall and annually by demographic, clinical, and risk groups. Risk factors associated with non-suppression were identified using univariable logistic regression. Results: Of 1,006 individuals diagnosed with HIV: 90% were male, 95% had at least one viral load test at or following diagnosis. Individuals averaged 1.8 (range: 1–5) and 2.5 (1–8) tests within 3- and 6-months of diagnosis, respectively. The likelihood of newly diagnosed persons achieving viral suppression increased year-on-year (p < 0.001); within 3-months from 19.6% in 2014 to 58.8% in 2018, and 6-months from 46.9% to 82.2%. Viral suppression was more common among older age-groups and individuals with lower CD4 counts (<350 cell/μL) at diagnosis, and lower among those with another BBV or STI pre/at diagnosis, and injecting drug users (IDUs). The largest year-on-year improvements were among older age-groups and men who have sex with men who were also IDUs. Risk factors for non-suppression included: CD4+ count ≥350 cells/μL (OR 3-months: 1.5, 95% CI: 1.1–2.0; 6-months: 1.6, 1.2–2.4) or unknown (OR 3-months: 15.5, 4.7–51.5; 6-months: 4.7, 2.5–8.9), and recent acquisition (OR 3- and 6-months: 1.3, 1.0–1.8, 1.0–1.7). STI infection pre/at diagnosis was a risk factor at 6-months (OR 1.4, 1.1–1.9). Conclusion: We found increasing viral suppression following HIV diagnosis between 2014 and 2018 in our cohort. This is likely to be related to health service and monitoring improvements. These are important metrics for HIV control, improving our understanding of year-to-year progress for population groups and enabling non-suppression risk factors to be understood and addressed.