Potential Risk Factors of Drug-Related Problems in Hospital-Based Mental Health Units: A Systematic Review

Introduction Reducing the occurrence of drug-related problems is a global health concern. In mental health hospitals, drug-related problems are common, leading to patient harm, and therefore understanding their potential risk factors is key for guiding future interventions designed to minimise their frequency. Objective The aim of this systematic review was to explore the potential risk factors of drug-related problems in mental health inpatient units. Methods Six databases were searched between 2000 and 2021 to identify studies that investigated the potential risk factors of drug-related problems in adults hospitalised in mental health inpatient units. Data extraction was performed by two authors independently and Allan and Barker’s criteria were used for study quality assessment. Studies were categorised based on drug-related problem types and potential risk factors were stratified as patient, medication, and hospital related. Results A total of 22 studies were included. Studies mostly originated in Europe (n = 19/22, 86.4%), and used a multivariable logistic regression to identify potential risk factors (n = 13, 59%). Frequently investigated factors were patient age (n = 14/22), sex (n = 14/22) and the number of prescribed medications (n = 14/22). Of these, increasing the number of prescribed medications was the only factor consistently reported to be significantly associated with the occurrence of most types of drug-related problems (n = 11/14). Conclusions A variety of patient, medication and hospital-related potential risk factors of drug-related problems in mental health inpatient units were identified. These factors could guide the development of interventions to reduce drug-related problems such as pharmaceutical screening tools to identify high-risk patients for timely interventions. Future studies could test a wider range of possible factors associated with drug-related problems using standardised approaches. Clinical Trial Registration PROSPERO: CRD42021279946.