Progression of non-anemic macrocytosis to anemia in HIV-positive persons receiving zidovudine-containing regimens in a resource-limited setting

Background Non-anemic macrocytosis is frequently observed among HIV-positive persons treated with zidovudine in resource-limited settings. Although zidovudine-associated anemia is well recognized, the probability and predictors of progression from non-anemic macrocytosis to anemia are still unknown. Methods A retrospective cohort study was conducted among HIV-positive persons receiving zidovudine-containing antiretroviral therapy (ART) with non-anemic macrocytosis. Kaplan-Meier and Cox regression analyses were used to determine the probability and predictive factors of progression from non-anemic macrocytosis to anemia, respectively. Results Of 318 HIV-positive persons, 59.4% were male; mean age was 44.3 years. The median follow-up duration was 5.8 years. The probabilities of progression to anemia at 1, 3 and 4 years were estimated at 9.4, 17.3 and 21.3%, respectively. Almost all anemia was mild asymptomatic. Duration of zidovudine use [hazard ratio (HR) = 1.141; 95% confidence interval (CI),1.036-1.256; p = .007], CD4 count prior to start zidovudine [HR = 0.991; 95%CI,0.982-0.999; p = .038], and hematocrit level at development of macrocytosis [HR = 0.683; 95%CI,0.541-0.861; p = .001] were significant factors to predict progression to anemia. Conclusion Non-anemic macrocytosis in HIV-positive persons receiving zidovudine-containing ART can progress to anemia. Longer duration of zidovudine use, lower CD4 cell counts at ART initiation, and lower hematocrit level at development of macrocytosis are predictive factors for progression to anemia.