Hybrid And In-Person Care for Dual Diagnosis Patients: Utilization Patterns and Impact on Dropout Across COVID-19 Public Health Periods

BACKGROUND: The COVID-19 pandemic prompted a rapid expansion of telehealth services in patients with substance use disorders (SUD) and comorbid mental health conditions (dual diagnosis). However, evidence on the effectiveness and utilization of hybrid care (combining in-person and telehealth modalities) in this population remains limited. OBJECTIVE: This study aims to analyze the use of a hybrid treatment (telehealth and in-person treatment) among patients with dual pathology across three distinct periods-before, during, and after COVID-19-related public health measures-and to assess the impact of hybrid care on treatment dropout rates. METHODS: A retrospective observational study was conducted using electronic health records (EHR) from 6,365 outpatients diagnosed with SUD and comorbid mental disorders, between March 2018 and September 2023. Patients were classified by treatment modality (in-person vs. hybrid) and period of care. Bivariate statistics and Cox regression analyses were performed to identify predictors of treatment dropout, accounting for demographic and clinical variables. RESULTS: Hybrid care utilization increased significantly during the pandemic and remained elevated post-pandemic. Women and patients with opioid use disorder were more likely to receive hybrid care. Patients receiving hybrid therapy had significantly lower dropout rates and longer treatment durations. Also, patients in coordinated care (addiction and mental health centers) show lower rates of dropout. Cox regression confirmed that hybrid care was the strongest predictor of reduced treatment dropout across all periods. CONCLUSIONS: Hybrid care models enhance treatment retention among dual diagnosis patients, underscoring the need to maintain and optimize telehealth options for this high-risk group even beyond pandemic-related restrictions.