Prevalence and clinical correlates of HIV viremia ('blips') in patients with previous suppression below the limits of quantification.

OBJECTIVE: To examine the prevalence and clinical correlates of subsequently measurable viremia in HIV-infected patients who have achieved viral suppression below the limits of quantification (< 50 copies/ml). DESIGN: Non-randomized dynamic cohort study of ambulatory HIV patients in nine HIV clinics in eight cities. PATIENTS: Patients had two consecutive HIV-1 RNA levels < 50 copies/ml (minimum, 2 months apart) that were followed by at least two more viral level determinations while remaining on the same antiretroviral therapy (ART) between January 1997 and June 2000 (median 485 days). Transiently viremic patients were defined having a subsequently measurable viremia but again achieved suppression < 50 copies/ml. RESULTS: Of the 448 patients, 122 (27.2%) had transient viremia, 19 (4.2%) had lasting low-level viremia and 33 (7.4%) had lasting high-level viremia (defined as 50-400 and > 400 copies/ml, respectively). Only 16 (13.1%) of those who had transient viremia later had persistent viremia > 50 copies/ml. The occurrence of transient viremia did not vary with whether the patient was ART-naive or experienced (P = 0.31), or currently taking protease inhibitors or not (P = 0.08). On consistent ART, the median percentage increase in CD4 cell count was statistically different between subgroups of our cohort (Kruskal-Wallis, P = 0.002). CONCLUSIONS: Transiently detectable viremia, usually 50-400 copies/ml, was frequent among patients who had two consecutive HIV-1 RNA levels below the limits of quantification. In this analysis, such viremia did not appear to affect the risk of developing lasting viremia. Caution is warranted before considering a regimen as 'failing' and changing medications.

Influence of coinfection with hepatitis C virus on morbidity and mortality due to human immunodeficiency virus infection in the era of highly active antiretroviral therapy.

To ascertain the impact of hepatitis C virus (HCV) infection on human immunodeficiency virus (HIV) disease progression and associated death in the era of highly active antiretroviral therapy (HAART), we examined mortality rates, the presence of other diseases, and antiretroviral use in an observational cohort of 823 HIV-infected patients with and without HCV coinfection during the period of January 1996 through June 2001. Analyses were used to compare patient characteristics, comorbid conditions, and survival durations in HIV-infected and HIV-HCV-coinfected patients. HIV-HCV-coinfected persons did not have a statistically greater rate of acquired immunodeficiency syndrome or of renal or cardiovascular disease, but they did have more cases of cirrhosis and transaminase elevations. There were proportionately more deaths in the HIV-HCV-coinfected group. Age, baseline CD4+ cell count, and duration of HAART were significantly associated with survival, but HCV infection was not. HAART use was a strong predictor of increased duration of survival, suggesting that treatment is more important to survival than is HCV coinfection status.