Sex, race, and geographic region influence clinical outcomes following primary HIV-1 infection

Abstract

Background: It is unknown whether sex and race influence clinical outcomes following primary human immunodeficiency virus type 1 (HIV-1) infection.

Methods: Data were evaluated from an observational, multicenter, primarily North American cohort of HIV-1 seroconverters.

Results: Of 2277 seroconverters, 5.4% were women. At enrollment, women averaged .40 log₁₀ fewer copies/mL of HIV-1 RNA (P < .001) and 66 more CD4(+) T cells/μL (P = .006) than men, controlling for age and race. Antiretroviral therapy (ART) was less likely to be initiated at any time point by nonwhite women and men compared to white men (P < .005), and by individuals from the southern United States compared to others (P = .047). Sex and race did not affect responses to ART after 6 months (P > .73). Women were 2.17-fold more likely than men to experience >1 HIV/AIDS-related event (P < .001). Nonwhite women were most likely to experience an HIV/AIDS-related event compared to all others (P = .035), after adjusting for intravenous drug use and ART. Eight years after diagnosis, >1 HIV/AIDS-related event had occurred in 78% of nonwhites and 37% of whites from the southern United States, and 24% of whites and 17% of nonwhites from other regions (P < .001).

Conclusions: Despite more favorable clinical parameters initially, female HIV-1-seroconverters had worse outcomes than did male seroconverters. Elevated morbidity was associated with being nonwhite and residing in the southern United States.

Figure 1.

Linear model of baseline human immunodeficiency virus (HIV) RNA concentration (A) and CD4⁺ T cell count (B) as a function of age, race, and sex. Viral load was lower (P < .001) and CD4⁺ T cell count was higher (P = .005) in women than in men. Combining sexes, viral load was higher in Hispanics (P = .007) and whites (P < .001) compared with individuals of other races, whereas white individuals had higher CD4⁺ T cell counts than did black (P = .02) and Hispanic (P = .02) individuals. Other race/ethnicity pairwise differences were not statistically significant.

Figure 2.

Extended Cox proportional hazards model of time to initiation of antiretroviral therapy (ART) in acute (A) and recent (B) human immunodeficiency virus (HIV) infection. All race sex pairwise comparisons are statistically significant (P < .04) except that for nonwhite women versus nonwhite men (P = .08).

Figure 3.

Kaplan-Meier curves for time to human immunodeficiency virus (HIV)–related (A) and AIDS-defining events (B) by sex and race, and time to HIV-related and AIDS-defining events by region (C). Nonwhite women were more likely to experience >1 HIV-related (P < .001) (A) and AIDS-defining illness (P = .007) (B) than all others over the entire period of study follow-up. For HIV-related events, significant pairwise comparisons included nonwhite women versus white women (P < .001), nonwhite women versus nonwhite men (P = .02), nonwhite women versus white men (P < .001), white women versus white men (P < .001), and nonwhite men versus white men (P = .02). For AIDS-defining illnesses, nonwhite women were significantly more likely to experience >1 event than were white women (P = .02). Other pairwise comparisons were not statistically different. Geographic region combined with race significantly impacted likelihood of HIV- and/or AIDS-related events (C). Regions outside of the southern United States, including international regions, were combined because there were similar and not significant differences among them in terms of morbidity. Nonwhites and whites in the southern United States were significantly more likely to experience >1 HIV- and/or AIDS-related event than both race categories from all other regions (P < .001). No significant differences were seen between whites and nonwhites within the category “all other regions” (P = .2). Removal of international sites from the analysis did not substantively change the results in any way.