Figure 1.

Association of tumor necrosis factor α (TNF-α) level with viral load set point, CD4⁺ T-cell count, and early human immunodeficiency virus type 1 (HIV-1) disease progression. A and B, TNF-α and interferon γ (IFN-γ) levels were measured in study subjects and compared to the viral load set point (A) and CD4⁺ T-cell count (B) at the time of testing, using Spearman rank correlation analysis. Nominal unadjusted 2-sided P values are presented. C, The TNF-α level was significantly higher (as determined by the Mann–Whitney test) in subjects with a CD4⁺ T-cell count of <500 cells/mm³. D and E, Log-rank analysis was used to determine the interval between testing and reaching the end points of a CD4⁺ T-cell count of <500 cells/mm³ (D) and initiation of antiretroviral therapy (ART; E) Subjects were categorized as having a high or low TNF-α level, IFN-γ level, or CD4⁺ T-cell count, by using the mean value as a cutoff; the median value was used as a cutoff for viral load due to the logarithmic distribution. A P value of <.05 is considered statistically significant.