Emergency Department Use, Hospitalization, and Their Sociodemographic Determinants among Patients with Substance-Related Disorders: A Worldwide Systematic Review and Meta-Analysis.

Background: Identifying the determinants of emergency department (ED) use and hospitalization among patients with substance-related disorders (SRD) can help inform healthcare services and case management regarding their unmet health needs and strategies to reduce their acute care. Objectives: The present study aimed to identify sociodemographic characteristics, type of used drug, and risky behaviors associated with ED use and hospitalization among patients with SRD. Methods: Studies in English published from January 1st, 1995 to April 30th, 2022 were searched from PubMed, Scopus, Cochrane Library, and Web of Science to identify primary studies on ED use and hospitalization among patients with SRD. Results: Of the 17,348 outputs found, a total of 39 studies met the eligibility criteria. Higher ED use and hospitalization among patients with SRD were associated with a history of homelessness (ED use: OR = 1.93, 95%CI = 1.32-2.83; hospitalization: OR = 1.53, 95%CI = 1.36-1.73) or of injection drug use (ED use: OR = 1.34, 95%CI = 1.13-1.59; hospitalization: OR = 1.42, 95%CI = 1.20-1.69). Being female (OR = 1.24, 95%CI = 1.14-1.35), using methamphetamine (OR = 1.99, 95%CI = 1.24-3.21) and tobacco (OR = 1.25, 95%CI = 1.11-1.42), having HIV (OR = 1.70, 95%CI = 1.47-1.96), a history of incarceration (OR = 1.90, 95%CI = 1.27-2.85) and injury (OR = 2.62, 95%CI = 1.08-6.35) increased ED use only, while having age over 30  years (OR = 1.40, 95%CI = 1.08-1.81) and using cocaine (OR = 1.60, 95%CI = 1.32-1.95) increased hospitalization only among patients with SRD. Conclusions: The finding outline the necessity of developing outreach program and primary care referral for patients with SRD. Establishing a harm reduction program, incorporating needle/syringe exchange programs, and safe injection training with the aim of declining ED use and hospitalization, is likely be another beneficial strategy for patients with SRD.