Transient rebounds of low-level viraemia among HIV-infected patients under HAART are not associated with virological or immunological failure.

OBJECTIVE

To analyse whether blips are associated with a higher risk of virological or immunological failure than persistent undetectable viraemia (UND) among HIV-infected patients receiving HAART.

DESIGN

Retrospective cohort study.

SUBJECTS

Patients with blips or UND were selected from a prospective cohort of 330 patients under HAART for over 48 weeks. Blips were defined as detectable viraemia up to a maximum of 1000 copies/ml preceded by two consecutive visits and followed by one visit showing undetectable viraemia. Patients were included according to the following criteria: i) Blip group: patients that showed transient relapses of viraemia; ii) UND group: patients who had achieved UND on HAART before 24 weeks of therapy and that sustained viral suppression for four consecutive visits.

MAIN OUTCOME MEASURES

Virological and immunological failure.

RESULTS

Thirty seven (11%) and 65 (20%) patients showed blips and persistent UND, respectively. Virological failure was observed in three (8.1%) patients in the blip group and 11 (16.9%) patients in the UND group (P=0.25). The time to virological failure was shorter in the UND group (P=0.12). The rates of virological failure and the time to virological failure were similar between both groups after excluding patients with compliance <95%. The time to immunological failure was also similar in both groups (P=0.5). In a Cox model, only the use of saquinavir hard gel-based regimens was independently associated with the time to virological and immunological failure.

CONCLUSION

Patients under HAART with transient low-level viraemia are not at an increased risk of developing virological or immunological failure.