Figure 1.

Multivariable-adjusted Cox proportional-hazards analysis of neurocognitive impairment as a function of anemia. This analysis included 799 CHARTER (CNS HIV Antiretroviral Therapy Effects Research) study participants who were neurocognitively normal at baseline and had longitudinal follow-up and data from 2545 visits. Global deficit scores (GDS) obtained after the baseline visit were adjusted for practice effects. Time-dependent, Cox proportional-hazards regression models were adjusted for age, sex, race/ethnicity, highly active antiretroviral therapy (on or off), nadir CD4⁺ T-cell count, zidovudine use, mean corpuscular volume at baseline, premorbid IQ (Wide-Range Achievement Test III score), and non–human immunodeficiency virus–related comorbid conditions at entry.