Primary care app engagement was limited, with differences by substance type

BACKGROUND: Patient engagement with digital therapeutics for substance use disorder (SUD) in primary care remains poorly understood. We analyzed engagement in routine care and whether specific types of substance use are associated with greater engagement. METHODS: This real-world observational study analyzed 83 primary care patients prescribed reSET® or reSET-O®, US Food and Drug Administration-authorized digital therapeutics for SUD. Substance types (unhealthy alcohol, cannabis, and other drug use) were identified from routine health screens and clinical diagnoses. The primary outcome was progression through four engagement cascade milestones: app activation, user guide completion, completion of ≥  one module, and treatment completion. Vendor logfiles provided weekly module counts. Logistic regression evaluated associations between substance use and engagement, adjusting for age and sex. RESULTS: Overall, 50.6% of patients activated the app, 45.8% completed the guide, 38.6% completed ≥  one module, and 13.3% met the vendor-defined treatment completion criterion. Among those who activated it, the median number of modules completed was 4 (interquartile range 1-32); half of module users stopped by week 4. Unhealthy alcohol use was associated with higher odds of app activation, user guide completion, and completion of ≥  one module (adjusted odds ratios [95% confidence intervals] = 2.84 [1.10-7.66], 3.48 [1.32-9.82], and 3.67 [1.32-11.26], respectively). Cannabis and other drug use were not associated with engagement milestones. CONCLUSIONS: Engagement with prescription-based digital therapeutics in primary care varies by substance type and is concentrated in the first month of use. Overall, engagement remains limited. Future research should validate these findings and refine engagement strategies.