Trends in detectable viral load by calendar year in the Australian HIV observational database

Background Recent papers have suggested that expanded combination antiretroviral treatment (cART) through lower viral load may be a strategy to reduce HIV transmission at a population level. We assessed calendar trends in detectable viral load in patients recruited to the Australian HIV Observational Database who were receiving cART. Methods Patients were included in analyses if they had started cART (defined as three or more antiretrovirals) and had at least one viral load assessment after 1 January 1997. We analyzed detectable viral load (>400 copies/ml) in the first and second six months of each calendar year while receiving cART. Repeated measures logistic regression methods were used to account for within and between patient variability. Rates of detectable viral load were predicted allowing for patients lost to follow up. Results Analyses were based on 2439 patients and 31,339 viral load assessments between 1 January 1997 and 31 March 2009. Observed detectable viral load in patients receiving cART declined to 5.3% in the first half of 2009. Predicted detectable viral load based on multivariate models, allowing for patient loss to follow up, also declined over time, but at higher levels, to 13.8% in 2009. Conclusions Predicted detectable viral load in Australian HIV Observational Database patients receiving cART declined over calendar time, albeit at higher levels than observed. However, over this period, HIV diagnoses and estimated HIV incidence increased in Australia

Sexually Transmitted Infections:associations in persons with HIV on treatment.

Established HIV-infection, when associated with other sexually transmissible infections (STI), interacts with them in a number of different ways. To investigate some of these associations, we established a sub-cohort of ten sexual health clinics within a much larger prospective longitudinal cohort of HIV-positive people mostly on antiretroviral treatment (ART), the Australian HIV Observational Database (AHOD). The clinics collected additional data on STI diagnoses and treatments.Preliminary analysis (2005-11) showed a high incidence of four STI, namely, infectious syphilis, chlamydia, gonorrhoea, and genital warts. These were the first measurements of STI incidence among persons being treated for HIV in Australia. Predictive factors for an STI diagnosis (2010-2013) included age less than 30 years and being MSM, (similar to other cohorts) . We also found a history of prior STI as a risk factor for future STI diagnosis. This had not previously been described in HIV-positive populations, although it is an intuitive finding. Risk factors assist targetting of health promotion efforts. Our study of individuals in AHOD (2010-2015) followed for over 2,000 person-years, included many thousands of viral load measurements. We found no elevation in viral loads before, during, or after episodes of four STI. Our findings add to a convincing body of data that point toward the reduction of viral load by ART having a greater effect on HIV transmission than STI and their treatment.Being diagnosed with an STI in the first 5 years of follow-up (2010-2015) was not a risk factor for later detectable viral loads, measured in the following 3 years (2015-2018). Therefore, it does not necessarily follow that extra vigilance is required in individuals with STI, with respect to HIV-management, to ensure long-term viral suppression.Finally, we investigated the feasibility of using treatment records as surrogate markers for infectious syphilis and gonorrhea, in populations where consistent diagnosis data may be problematic. Overall, the number of treatments in 2010-2015 exceeded the number of diagnoses by a small amount, and risk factors were generally similar. We recommend further exploration of this concept