Developing and validating a clinical risk score to predict losses in the PISCIS cohort of people with HIV.

Background: People lost to follow-up (LTFU) from HIV care have an increased risk of worse health. The objective of this study is to create and validate a risk score to predict LTFU among PLWH in Catalonia and the Balearic Islands.

Methods: 6661 PLWH were included. LTFU were those without contact with HIV care for 12 months or more. Logistic regression models were used to assess the role of independent factors on LTFU. The validation included a 10-fold iteration to predict the performance of the regression model and the Area under the ROC Curve (AUC). Regression coefficients were rounded and summed to construct the score.

Results: Determinants of LTFU included being younger than 34 years (OR: 1.80, CI, 1.44-2.23), not having been born in Spain (OR: 1.32, 1.11-1.58), men who inject drugs (OR: 2.10, 1.38-3.19), having a detectable viral load (OR: 3.14, 2.47-3.99), and ≤2.5 years since HIV diagnosis (OR: 3.84, 3.10-4.75). The validation of determinants resulted in a mean AUC of 0.69 and the risk-score revealed that 28.8% had a medium and 3.4% a high risk of LTFU respectively.

Conclusions: Findings can be used to prevent LTFU in HIV care.