Prevalence of substance use and substance use disorder in medically ill patients: A cross-sectional, hospital-based study from India.

Background Untreated co-occurring substance use and substance use disorders (SUDs) in patients with medical conditions may be associated with unfavourable medical outcomes. Understanding the prevalence of substance use and SUDs among patients admitted to hospital for medical illness may help in developing appropriate strategies to manage SUDs in this population and improve the outcomes of medical illness. We assessed the prevalence of substance use and SUDs among patients admitted for medical illnesses and the association between substance use and medical illness. Methods This cross-sectional study was done in an in-patient setting in a multidisciplinary teaching medical institution in India. Using systematic sampling, adult patients admitted in various departments for at least 24 hours were interviewed using standard instruments by psychiatrists trained in the study methodology. Results Two hundred and ninety patients participated. Their mean (SD) age was 42.2 (15.6) years. One hundred and nine participants (37.6%) reported lifetime use of any psychoactive substance, with tobacco being the most common substance used (91, 31.4%), followed by alcohol (69, 23.8%) and cannabis (12, 4.1%). Lifetime alcohol use was significantly associated with diseases of the circulatory system. Lifetime use of any substance or of alcohol, and current use of any substance or tobacco were significantly associated with injuries, poisoning and other consequences of external causes. Conclusions A large proportion of patients hospitalized for medical illness reported the use of psychoactive substances or had SUDs. The use of some of these substances was also associated with injuries as well as diseases of the circulatory system.