13th Annual Conference of the British HIV Association 29 March–1 April 2007, Brighton, UK

PREDICTORS OF CLINICAL PROGRESSION AMONG HIV-1 POSITIVE PATIENTS STARTING HAART WITH CD4+ T-CELL COUNT ≥200/mm³

HIV Med 2007; 8(Suppl. 1):4 (abstract no. O16)

Carlo Torti¹, Carmine Tinelli², Giuseppe Lapadula¹, Franco Maggiolo³, Salvatore Casari⁴, Fredy Suter³, Lorenzo Minoli⁵, Chiara Pezzoli¹, Massimo Di Pietro⁶, Guglielmo Migliorino⁷, Eugenia Quiros-Roldan¹, Nicoletta Ladisa⁸, Laura Sighinolfi⁹, Francesca Gatti¹, Annalisa De Silvestri² and Giampiero Carosi^1
1University of Brescia, Brescia, Italy, ²Service of Biostatistics, IRCCS S. Matteo, Pavia, Italy, ³Ospedali Riuniti, Bergamo, Italy, ⁴Spedali Civili, Brescia, Italy, ⁵IRCCS S. Matteo, Pavia, Italy, ⁶S.M. Annunziata Hosp., Florence, Italy, ⁷Ospedale di Circolo, Busto Arsizio, Italy, ⁸Policlinico, Bari, Italy, ⁹S. Anna Hosp., Ferrara, Italy

BACKGROUND: Predictors of long-term clinical outcomes (either baseline or follow-up factors) among patients starting therapy with high CD4+ T-cell counts are largely unexplored.

OBJECTIVE:: To investigate risk factors of new AIDS defining events (ADE) and deaths in patients who initiated HAART at CD4+ T-cell count ≥200/mm³.

METHODS: Prospective observational cohort study. HIV-infected patients who initiated triple drug antiretroviral combinations between 1996 and 2002 and had a minimum of 1 month of follow-up were studied. Both baseline and time-updated variables were tested for prediction of ADE and deaths using Cox regression models.

RESULTS: A total of 896 HIV-infected patients initiated treatment with CD4+ T- cell count ≥200/mm³ in the stated period. After a median follow-up of 5.2 years, incidence of new ADE was 1.6 (95% CI 1.2–2) per 100 person-years of follow-up. Higher HIV-RNA (per 1 log₁₀ copies/mL increase, HR 1.5; 95% CI 1.1–2.1; P<0.009), occurrence of ADE prior to HAART initiation (HR 3; 95% CI 1.5–6.1; P<0.003) and longer delay from HIV diagnosis to antiretroviral therapy (per 1 year increase, HR 1.05; 95% CI 1.01–1.1; P<0.021) were predictors of ADE/death, independently from CD4+ T-cell count before treatment. Moreover, longer proportion of follow-up time spent with CD4+ T-cell count <200/mm³ (per 10 percent-points increase, HR 1.3; 95% CI 1.1–1.4; P<0.001) or without treatment (per 10% points increase, HR 1.1; 95% CI 1.04–1.3; P<0.006) were independently associated with higher risk of ADE/ death, whereas higher percentage of follow-up with CD4+ T-cell count >500/mm³ was protective (per 10% points increase, HR 0.8; 95% CI 0.77–0.9; P<0.002). A CD4+ T-cell count <350/mm³ before HAART initiation was associated with higher risk of ADE/death (HR 2.1; 95% CI 1.2–3.7; P<0.021), independently from other baseline factors. However, in the model including both baseline and time-updated factors, CD4+ T-cell count ≥350/mm³ at baseline was no longer significantly associated with the outcome (HR 1.4; 95% CI 0.8–2.4; P<0.297).

CONCLUSION: Maintenance of high CD4+ T-cell count and continuity of antiretroviral treatment were correlated with free-of-disease survival, independently from the CD4+ T-cell count at starting treatment however it was ≥200/mm³ in all patients. Patients who started treatment with CD4+ T-cell count ≥350/mm³ had better outcome, independently from other factors assessed at baseline, but not when viro-immunological and clinical evolutions were taken into account. Randomized controlled studies are urgently needed to clarify the optimal time to start HAART.

2007-03-29
O16

Copyright © 2007 - British HIV Association (BHIVA) Reproduction of this abstract (other than one copy for personal reference) must be cleared through the BHIVA Organising Secretariat 1 Mountview Court, 310 Friern Barnet Lane, London N20 0LD