Background:  Zidovudine (ZDV) is known to cause anemia, and there has been concern about its use in areas endemic for malaria and other causes of anemia. The Kisumu Breastfeeding Study (KiBS) is an ongoing single arm, phase 2b clinical trial to evaluate safety, tolerance, and utility of ZDV, lamivudine and nevirapine or nelfinavir from 34 weeks’ gestation through 6 months’ post-partum to reduce mother-to-child transmission (MTCT) among HIV-infected breastfeeding women in a resource-limited setting. Participants receive prenatal folate, iron, as well as intermittent preventive treatment with sulphadoxine-pyrimethamine and insecticide-treated bed-nets for malaria prevention. In addition, they receive treatment for common illnesses throughout the study.

Methods:  We determined prevalence of anemia at baseline (33 weeks’ gestation), delivery, and periodically until 18 months’ post-partum. Hemoglobin (Hb) was categorized using NIH DAIDS criteria Grade 1-2 (≤9.4 g/dL ≤7.0 g/dL), grade 3 or 4 (<7.0 g/dL). ZDV was discontinued for persistent hemoglobin <7.0 g/dL where no other cause was established. Blood was collected in EDTA, and hemoglobin measured using Beckman Coulter Counter.

Results:  Between July 2003 and August 2006, 303 women were screened; 5 (1.6%) were excluded because their hemoglobin was <7.0 g/dL; and 254 started the intervention. Median age was 25 years (range 17 to 41 years), median CD4 at enrolment = 392 cells/mm³ (range 43 to 1193), 48 (19%) had advanced HIV (ie, CD4 <200 or WHO stage 3/4). During the intervention, 13 (5.1%) developed grade 3 or 4 anemia of which 7 (2 with advanced HIV) were attributed to and required discontinuation of ZDV after a median duration of 10 weeks (range 4 to 26 weeks). At 6 months post-partum, 209 participants were still taking ART, 197 (94%) still on ZDV. The table demonstrates the percentage of women sampled by disease status and hemoglobin level.
Conclusions:  Grade 1-2 anemia was prevalent using U.S. norms at baseline in women with both advanced and earlier HIV disease. Few participants developed grade 3-4 anemia during 7 months on a HAART regimen with ZDV. Both groups showed significant improvement in hemoglobin levels while receiving routine care and treatment for causes of anemia.

Percentage of Women by Hb Category/Grade