Rapid disease progression in HIV-1 subtype C-infected South African women

Abstract

Background: Whereas human immunodeficiency virus (HIV) subtype B-infected individuals generally progress to AIDS within 8-10 years, limited data exist for other clades, especially from Africa. We investigated rates of HIV disease progression of clade C-infected South African women.

Methods: Prospective seroincidence cohorts in KwaZulu-Natal were assessed for acute HIV infection monthly (n = 245) or every 3 months (n = 594) for up to 4 years. Rapid disease progression was defined as CD4 decline to <350 cells/µL by 2 years postinfection. Serial clinical and laboratory assessments were compared using survival analysis and logistic regression models.

Results: Sixty-two women were identified at a median of 42 days postinfection (interquartile range, 34-59), contributing 282 person-years of follow-up. Mean CD4 count dropped by 39.6% at 3 months and 46.7% at 6 months postinfection in women with preinfection measurements. CD4 decline to <350 cells/µL occurred in 31%, 44%, and 55% of women at 1, 2, and 3 years postinfection, respectively, and to <500 cells/µL in 69%, 79%, and 81% at equivalent timepoints. Predictors of rapid progression were CD4 count at 3 months postinfection (hazard ratio [HR], 2.07; 95% confidence interval [CI], 1.31-3.28; P = .002), setpoint viral load (HR, 3.82; 95% CI, 1.51-9.67; P = .005), and hepatitis B coinfection (HR, 4.54; 95% CI, 1.31-15.69; P = .017). Conversely, presence of any of HLAB*1302, B*27, B*57, B*5801, or B*8101 alleles predicted non-rapid progression (HR, 0.19; 95% CI, .05-.74; P = .016).

Conclusions: Nearly half of subtype C-infected women progressed to a CD4 count <350 cells/µL within 2 years of infection. Implementing 2013 World Health Organization treatment guidelines (CD4 count <500 cells/µL) would require most individuals to start antiretroviral therapy within 1 year of HIV infection.

Keywords: HIV disease progression; acute HIV infection; subtype C; viral load; women.