Multimorbidity, psychoactive substance use and psychological distress among acute medically ill patients: a cross-sectional study.

Multimorbidity was associated with psychoactive medicinal drug and risky alcohol use, and psychological distress. Substance use was widespread, with alcohol and psychoactive medicinal drugs most frequently combined. Monitoring substance use among multimorbid patients is necessary to develop tailored treatments, and reduce burden on the healthcare system.