Incident Sexually Transmitted Infection As a Biomarker for High-risk Sexual Behavior After Diagnosis of Acute HIV

Background: Sexually transmitted infection (STI) diagnosis after diagnosis of acute HIV infection (AHI) indicates ongoing high-risk sexual behavior and possible risk of HIV transmission. We assessed predictors of STI acquisition and the effect of time since care entry on STI incidence in patients with AHI in care and receiving consistent risk-reduction messaging.

Methods: Data on incident gonorrhea, chlamydia, trichomoniasis, primary/secondary syphilis, demographic, and clinical risk factors were abstracted from medical charts for patients diagnosed as having AHI and engaged in care. Poisson regression models using generalized estimating equations were fit to estimate incidence rates (IRs), IR ratios, and robust 95% confidence intervals.

Results: Among 185 patients with AHI, 26 (14%) were diagnosed as having at least 1 incident STI over 709.4 person-years; 46 STIs were diagnosed during follow-up (IR, 6.8/100 person-years). The median time from HIV care entry to first STI diagnosis was 609 days (range, 168-1681 days). Men who have sex with men (P = 0.03), a shorter time between presentation to medical care and AHI diagnosis (P = 0.06), and STI diagnosis before AHI diagnosis (P = 0.0003) were predictors of incident STI. Sexually transmitted infection IR greater than 1 year after entering care was double that of patients in care 1 year or less (IR ratio, 2.0; 95% confidence interval, 0.8-4.9). HIV viral load was above the limits of detection within 1 month of 11 STI diagnoses in 6 patients (23.1%) (median, 15,898 copies/mL; range, 244-152,000 copies/mL).

Conclusions: Despite regular HIV care, STI incidence was high among this primarily young, men who have sex with men AHI cohort. Early antiretroviral initiation may decrease HIV transmission given ongoing risk behaviors despite risk-reduction messaging.