Background: After HIV diagnosis and linkage to care, achieving and sustaining viral load (VL) suppression has implications for patient outcomes and secondary HIV prevention. We evaluated factors associated with expeditious VL suppression and cumulative VL burden among patients establishing outpatient HIV care.
Methods: Patients initiating HIV medical care from January 2007 to October 2010 at the University of Alabama at Birmingham and University of Washington were included. Multivariable Cox proportional hazards and linear regression models were used to evaluate factors associated with time to VL suppression (<50 copies/mL) and cumulative VL burden, respectively. Viremia copy-years, a novel area under the longitudinal VL curve measure, was used to estimate 2-year cumulative VL burden from clinic enrollment.
Results: Among 676 patients, 63% achieved VL <50 copies per milliliter in a median 308 days. In multivariable analysis, patients with more time-updated "no show" visits experienced delayed VL suppression (hazard ratio = 0.84 per "no show" visit, 95% confidence interval = 0.76 to 0.92). In multivariable linear regression, visit nonadherence was independently associated with greater cumulative VL burden (log(10) viremia copy-years) during the first 2 years in care (Beta coefficient = 0.11 per 10% visit nonadherence, 95% confidence interval = 0.04 to 0.17). Across increasing visit adherence categories, lower cumulative VL burden was observed (mean ± standard deviation log(10) copy × years/mL); 0%-79% adherence: 4.6 ± 0.8; 80%-99% adherence: 4.3 ± 0.7; and 100% adherence: 4.1 ± 0.7 log(10) copy × years/mL, respectively (P < 0.01).
Conclusions: Higher rates of early retention in HIV care are associated with achieving VL suppression and lower cumulative VL burden. These findings are germane for a test and treat approach to HIV prevention.