Incidence and Determinants of COVID-19 in Patients Seeking Treatment for Substance Use Disorder: A Patient-Based Linkage Study.

This study did not find higher cumulative incidence of COVID-19 infection among people with SUD in Catalonia in 2020, despite the clinical vulnerability of this population and their social disadvantage. However, differences were seen in the cumulative incidence of COVID-19 according to the substance for which treatment was sought. For example, those with alcohol dependence had a higher rate than those dependent on heroin. Further studies are needed to determine the factors contributing to these differences.