Disengagement and reengagement of HIV continuum of care in a single center cohort in northern Italy

Background: Despite the progress in HIV care, adherence to follow up remains critical. Disengagement impairs the benefit of HIV care and the increasing number of data that associates failed retention with worse outcomes has led public health institutions to consider retention in care as a new tool to fight against HIV pandemic. Objective: The aim of this retrospective, observational study was to estimate the burden of disengagement and reengagement in care in our HIV cohort and to identify the characteristics of our LTFU and reengaged patients. Moreover, we build our cascade of care to explore how closely our center aligned with the "90-90-90" targets. Methods: From the local electronic database we extracted all HIV-infected patients with at least one contact with HIV Clinic between 2012 and 2018 excluding deceased and transferred patients. Our definition of LTFU was based on the lack of any visit during at least 1 year after the last visit. Patients re-engaged were defined as those firstly considered as LTFU patients who subsequently were newly linked to HIV care. Results: About 8% of patients were lost to follow up during the period of study, with a rate of less than 2% per year and 14.1% of them were re-engaged in care. The cascade of care shows, among HIV cases diagnosed between 2011 and 2018, 86.7% patients retained in care, 94.1% of whom were on cART and 95.6% of whom were virologically suppressed. A higher attrition was found among infections diagnosed since 2011 than before 2011, such as women, patients coming from foreign countries and those with poor virological control. Conclusions: The retention rate found in our cohort is high and is in accordance with the 90-90-90 strategy. Nevertheless, understanding disengagement and re-engagement determinants is important to strengthen retention in care in the most fragile population.