Interruption of antiretroviral therapy in chronically HIV-infected patients

BACKGROUND AND OBJECTIVE: To describe the immunological, virological and clinical outcomes of HIV-infected patients who stop antiretroviral therapy (ART) and to identify the factors related to durability. PATIENTS AND METHOD: Retrospective study of patients who interrupt therapy after six months without clinical events, level of CD4+ >= 500 cells/mu l and HIV RNA >= 5.000 copies/ml (3,7 log(10)). RESULTS: In October 2004, 44 patients were included, 32 (72%) of them were stables after one year of ART cessation (group A) and 12 (28%) patients had to restart therapy due to a decreased CD4+ count < 300 cells/mu l (group B). Both groups were compared. CD4 cell count nadir (414 cells/mu l [199] versus 171 cells/mu l [107]; p = 0.000) and CD4+ count level at time of ART stop (920 [302] cells/mu l versus 633 cells/mu l [177] p = 0.004) showed differences with statistical significance. The most important CD4+ count fall was observed at third month after stopping ART; 588 cells/mu l (288) on group A and 382 cells/mu l (167) on group B. The mean time without ART was 27 months on group A and 7 months on group B. Two patients had acute retroviral syndrome, and one had Pneumocystis jiroveci pneumonia. Cholesterol levels were 199 mg/dl (42) and triglycerides 257 mg/dl (271) on ART and during interruption decreased to 155 (38) and 165 (122) mg/dl respectively. After multivariate analysis, a CD4+ count nadir > 200 cells/mu l (p = 0,0005; OR = 0,12; 95% CI, 0.036-0,398) and a CD4+ count at time of ART stop > 800 cells/mu l (p = 0104; OR: 0,11; Cl 95%: 0,015-0,936) were independently related to durability of therapy interruption. CONCLUSIONS: Prolonged discontinuation of ART guided by CD4+ response causes a low morbi-mortality. The cell count CD4+ nadir and the CD4+ count at time of ART cessation are protective factors of durability. An improvement of metabolic parameters is observed during the discontinuation of ART.