Haemoglobin and anaemia in the SMART study

Background: Data from randomized trials on the development of anaemia after interruption of therapy are not well-described. Methods: A total of 2,248 patients from the SMART study were included. We used Cox proportional hazards models to investigate development of new (≤12 mg/dl for females and ≤14 mg/dl for males) or worsening (≤8 mg/dl if anaemic at randomization) anaemia and Poisson regression analyses to explore the relationship between anaemia and the development of AIDS, death or non-AIDS events. Results: Overall, 759 patients developed new or worsening anaemia: 420/1,106 (38.0%) in the drug conservation (DC) arm and 339/1127 (30.1%) in the viral suppression (VS) arm (P<0.0001). At 4 months after randomization, patients in the DC arm had a significantly increased risk of developing new or worsening anaemia (adjusted relative hazard 1.56, 95% CI 1.28-1.89). Currently anaemic patients had an increased incidence of AIDS (adjusted incidence rate ratio [IRR] 2.31, 95% CI 1.34-3.98), death (adjusted IRR 2.19, 95% CI 1.23-3.87) and non-AIDS events (adjusted IRR 2.98, 95% CI 2.01-4.40) compared to non-anaemic patients. Conclusions: Patients who interrupted combination antiretroviral therapy had a higher risk of new or worsening anaemia. Anaemic patients had a higher incidence of AIDS, non-AIDS defining events or deaths, possibly due to deteriorating health and subclinical disease.