Impact of COVID-19 on Substance Use Disorder Treatment: Examining the Influence of In-Person and Telehealth Intervention on Outcomes Using Real-World Data.

: The COVID-19 health crisis challenged healthcare systems around the world, leading to restrictions in access to face-to-face healthcare services, and forcing rapid adaptation to telehealth services. At present, there is a gap in the functioning of this adaptation in drug-dependence centres. The present study analyses, over four years, care indicators on the care modality (face-to-face vs. hybrid), the patient profile and the impact on retention in treatment. : Retrospective observational study with data collected between 14 March 2019 and 21 June 2023. The electronic health records of 44,930 patients were analysed according to different moments and selected based on the different health measures imposed by the COVID-19 pandemic. Patients were classified according to whether they received an in-person or hybrid intervention. Bivariate statistics and logistic regression analysis were applied. : The trend over time shows an increase in the number of patients seen in addiction centres. However, no notable changes within the in-person care modality and a modest increase in telehealth services are observed. Telehealth is primarily used among patients with opiate addiction, as well as with those with comorbid mental disorders. Logistic regression analysis shows that patients in a hybrid modality are more likely to remain in treatment. : Results show that hybrid care is associated with higher patient retention rates. Despite this, different profiles are mostly treated with in-person interventions rather than hybrid modalities. Future studies should explore how to generalise personalised hybrid care among SUD patients considering factors such as patients' educational level, employment status or accessibility to mental health services.