Risk of high-level viraemia in HIV-infected patients on successful antiretroviral treatment for more than 6 months.

OBJECTIVES: According to the Swiss Federal Commission for HIV/AIDS, HIV-infected patients on successful antiretroviral treatment have a negligible risk of transmitting HIV sexually. We estimated the risk that patients considered to have an undetectable viral load (VL) are actually viraemic. METHODS: A Danish, population-based nationwide cohort study of HIV-infected patients with VL <51 HIV-1 RNA copies/mL for more than 6 months was carried out for the study period 2000-2008. The observation time was calculated from 6 months after the first VL <51 copies/mL to the last measurement of VL or the first VL >50 copies/mL. The time at risk of transmitting HIV sexually was calculated as 50% of the time from the last VL <51 copies/mL to the subsequent VL if it was >1000 copies/mL. The outcome was the time at risk of transmitting HIV sexually divided by the observation time. RESULTS: We identified 2680 study subjects contributing 9347.7 years of observation time and 56.4 years of risk of transmitting HIV (VL>1000 copies/mL). In 0.6% [95% confidence interval (CI) 0.5-0.8%] of the overall observation time the patients had VL >1000 copies/mL. In the first 6 months this risk was substantially higher (7.9%; 95% CI 4.5-11.0%), but thereafter decreased and was almost negligible after 5 years (0.03%; 95% CI 0.0-0.2%). The risk was higher in injecting drug users, but otherwise did not differ between subgroups of patients. CONCLUSION: The risk of viraemia and therefore the risk of transmitting HIV sexually are high in the first 12 months of successful antiretroviral treatment, but thereafter are low.

Impact of hepatitis B virus co-infection on response to highly active antiretroviral treatment and outcome in HIV-infected individuals: a nationwide cohort study.

BACKGROUND: The impact of chronic hepatitis B virus (HBV) infection on viral suppression, immune recovery and mortality in HIV-1 infected patients on highly active antiretroviral treatment (HAART) is a matter of debate. The impact of HBeAg status is unknown. METHODS: This prospective cohort study included all adult Danish HIV-1 infected patients who started HAART between 1 January 1995 and 1 December 2006 (3180 patients). Patients were classified as chronic HBV-infected (6%), HBV-negative (87%) or HBV-unknown (7%). HBV-positive patients were divided into HBeAg-positive or -negative (3.0 vs. 2.6%). Study endpoints were viral load, CD4 cell count and mortality. RESULTS: HBV co-infection had no impact on response to HAART regarding viral suppression or immune recovery. HBV co-infection was associated with several outcomes: overall mortality [mortality rate ratio (MRR) 1.5; 95% confidence interval (CI) 1.1-2.1], liver-related mortality (MRR 4.0; 95% CI 1.6-9.9) and AIDS-related deaths (MRR 1.7; 95% CI 1.0-3.0). The presence of HBeAg did not influence patients' response to HAART. CONCLUSIONS: In HIV patients, chronic HBV infection has no impact on response to HAART concerning viral load and increase in CD4 cell count. However, co-infected patients have an increased mortality compared to HIV-monoinfected patients.