Loss to follow-up and re-linkage to care in a single cohort study: who do we re-link to care?

Purpose: Describe the HIV-infected patients lost to follow-up (LTFU) at our Centre and identify variables that might predict a subsequent re-linkage to care (RLTC). Method: We conducted a single center, retrospective study including patients followed at the Infectious Diseases Clinic of San Martino Policlinic Hospital, Genoa. LTFU was defined as missing appointments for both visits and exams for≥12 months. All patients LTFU during the year 2015, who were already in care at the beginning of the previous year, were included. All RLTC up to December 2018 were registered. Data were retrieved through medical records and the electronic MedInfo database. The possible association of different variables with RLTC was assessed through univariable logistic regression model. Results: Sixty-three patients were enrolled, of whom 32 (50.8%) re-entered care. Median time between LTFU and RLTC was 1 year (range 1–3 years). Median viral load at RLTC was 46.5 copies/mL (IQR 0–1500 copies/mL). Seventeen patients (53.1%) had undetectable viral load (HIV RNA<50 copies/mL) at RLTC. Other characteristics of the two populations are illustrated in table 1. At univariable logistic regression, only age showed a statistically significant association with RLTC (OR 0.9; 95% CI 0.9–1.0; p=0.033). No multivariable analysis was performed due to the small sample size. Conclusion: To maintain linkage to care is crucial in the cascade of care of HIV-infected patients. Half of the patients we LTFU in 2015 re-entered care after a median time of 1 year; half of them had an undetectable viral load upon re-linkage, testifying that they carried on antiretroviral treatment despite the apparent LTFU. Younger age was the only factor we found could predict the re-entrance in care. Limitations to the interpretability of our data stem from the small sample size and the retrospective design of the study, with a consistent amount of missing data.