Prognostic Importance of Anaemia in HIV Type-1-Infected Patients Starting Antiretroviral Therapy: Collaborative Analysis of Prospective Cohort Studies

Background In HIV type-1-infected patients starting highly active antiretroviral therapy (HAART), the prognostic value of haemoglobin when starting HAART, and of changes in haemoglobin levels, are not well defined. Methods We combined data from 10 prospective studies of 12,100 previously untreated individuals (25% women). A total of 4,222 patients (35%) were anaemic: 131 patients (1.1%) had severe (<8.0 g/dl), 1,120 (9%) had moderate (male 8.0–<11.0 g/dl and female 8.0–<10.0 g/ dl) and 2,971 (25%) had mild (male 11.0–<13.0 g/dl and female 10.0–<12.0 g/dl) anaemia. We separately analysed progression to AIDS or death from baseline and from 6 months using Weibull models, adjusting for CD4 + T-cell count, age, sex and other variables. Results During 48,420 person-years of follow-up 1,448 patients developed at least one AIDS event and 857 patients died. Anaemia at baseline was independently associated with higher mortality: the adjusted hazard ratio (95% confidence interval) for mild anaemia was 1.42 (1.17–1.73), for moderate anaemia 2.56 (2.07–3.18) and for severe anaemia 5.26 (3.55–7.81). Corresponding figures for progression to AIDS were 1.60 (1.37–1.86), 2.00 (1.66–2.40) and 2.24 (1.46–3.42). At 6 months the prevalence of anaemia declined to 26%. Baseline anaemia continued to predict mortality (and to a lesser extent progression to AIDS) in patients with normal haemoglobin or mild anaemia at 6 months. Conclusions Anaemia at the start of HAART is an important factor for short- and long-term prognosis, including in patients whose haemoglobin levels improved or normalized during the first 6 months of HAART.