Role of emergency departments in HIV screening in Barcelona (Spain) and impact of a targeted opt-in strategy for HIV testing

BackgroundUndiagnosed HIV-infected patients are mainly responsible for viral transmission in Western countries. Emergency departments (EDs) could represent a strategic point in healthcare systems to uncover HIV infection.ObjectiveThis study aimed to analyze the time trends of HIV testing in EDs in Barcelona (Spain) and investigate if EDs have changed HIV screening patterns after the implementation of a targeted opt-in strategy for HIV testing.DesignThis is a quasiexperimental (pre/post) study.Setting and participantsMonthly HIV tests performed by Microbiology Departments of four hospitals in Barcelona were recorded over 78 months, classified as ordered by ED or at other healthcare levels. Monthly ED attendances were compiled, along with new HIV diagnoses.InterventionImplementation of an opt-in strategy to test every ED patient with targeted conditions (community-acquired pneumonia, herpes zoster, mononucleosis syndrome, chemsex, postexposure prophylaxis, sexually transmitted diseases) in addition to other classical reasons for HIV testing.Outcome measures and analysisDetermination of trends over time in HIV screening and new diagnoses in EDs during the 60-month preintervention and 18-month postimplementation periods, and estimation of the impact of intervention using interrupted time series analyses.Main resultsA total of 659 885 HIV tests were performed, with 11 442 (1.7%) being ordered by EDs (0.29% of ED comers were tested), and 287 new HIV diagnoses made (positivity rate: 2.8%). During the preintervention period, HIV testing increased over time (overall and in EDs), new HIV diagnoses in EDs remained stable, and the rate of positive HIV tests decreased. The intervention increased the monthly average of HIV tests ordered in the ED by 106 (95% CI = 86-125), proportion of ED comers screened by 0.075% (95% CI = 0.032-0.118), and proportion of HIV tests made in Barcelona performed by EDs by 0.728% (95% CI = 0.424-1.032), but had no impact on new HIV diagnoses and rate of positive HIV tests in the EDs.ConclusionIn the last years, HIV screening in Barcelona increased, with EDs having a significant and increasing role in the overall HIV testing in Barcelona. The implementation of a targeted opt-in strategy for HIV screening in EDs increased the number of HIV tests performed, but not the number of HIV diagnoses made in EDs.