Effect of once-daily FDC treatment era on initiation of cART

OBJECTIVES Combination antiretroviral therapy (cART) is associated with increased survival among HIV-infected persons. Yet, no research to date has examined whether introduction of once-daily fixed-dosed combinations (FDC) affects the likelihood of cART initiation. We aimed to determine whether implementation of once-daily FDC regimens was associated with changes to cART initiation. We also identified clinical, treatment regimen, and provider characteristics possibly associated with cART initiation. STUDY DESIGN Retrospective observational analysis. METHODS We queried electronic medical records between July 1999-June 2006 to identify incident cases of detectable HIV infection in antiretroviral-naïve adults. Cox regression with time-dependent covariates was used to examine the effects of once-daily FDC era, clinical, provider, and treatment regimen characteristics on cART initiation. RESULTS Once-daily FDC availability did not change the likelihood of cART initiation, but other characteristics were associated with an increased likelihood: AIDS diagnosis, above-median daily pill consumption, and 16+ yrs of physician HIV experience. Decreased likelihood of cART initiation was associated with CD4 201-350 cells/μL, HIV RNA < 100,000 copies/mL, and with CD4 > 350 cells/μL (any HIV RNA level), compared to CD4 ≤ 200 cells/μL. CONCLUSION Availability of once-daily FDC-based regimens did not affect likelihood of cART initiation. Patient clinical characteristics appear to be more important predictors of cART initiation.