Predictors of clinical severity in subjects attending the Emergency Department for substance use: a ten-year cross-sectional study.

Abstract Objective Substance-related referrals to the Emergency Department (ED) are rising. Multiple substance use is frequent, and psychiatric patients represent a high-risk population. Our study aimed at identifying risk factors for increased severity in ED attendances for substance use. Methods We retrospectively evaluated consecutive patients attending the ED over ten years for substance-related problems, subdivided according to the triage code as having a life-threatening (LT), potentially life-threatening (P-LT), and non-life-threatening (N-LT) condition. Results Substance/drug intake for deliberate self-harm was a risk factor for being classified as LT compared to both P-LT (OR = 6.357; p ≤ 0.001) and N-LT (OR = 28.19; p ≤ 0.001). Suicide attempts (OR = 4.435; p = 0.022) and multiple substance use (OR = 1.513; p = 0.009) resulted as risk factors for P-LT, compared to N-LT. Psychiatric diagnosis (OR = 1.942; p = 0.042) and multiple substance use (OR = 1.668; p = 0.047) were risk factors for being classified as LT rather than N-LT. Conclusions In our sample, self-harming overdoses were the strongest risk factor for highest overall severity in a real-world setting. Psychiatric disorders and multiple substance use also increased the risk for greater severity at presentation. Substance use worsens patients' clinical picture and management, suggesting the need for consultation-liaison psychiatry services in emergency contexts and highlighting the role of EDs as key sites for identification and early intervention.