Characteristics of Unidentified Patients: Clinical, Structural, and Social Challenges in a Public Hospital

Unidentified patients pose challenges in emergency care due to missing clinical history and identification, impacting patient safety and decision-making. Despite known risks, little is understood about this group in middle-income countries.

To describe the epidemiological profile and the clinical, structural, and social challenges that influence the care of unidentified patients in a public teaching hospital.

This retrospective cohort study was conducted from January 2019 to December 2022 in the emergency department (ED) of a public teaching hospital in Belo Horizonte, Brazil. Data from unidentified patients were extracted from electronic medical records, including demographics, admission reasons, risk classification, clinical management, outcomes, and hospital length of stay. Multivariate logistic regression was used to identify factors associated with adverse outcomes, adjusting for clinical and sociodemographic variables.

Among 2,425 unidentified ED admissions, 332 cases were sampled using a finite population correction formula. Of these, 81.6% were male; median age was 32 years (interquartile range 26-43). Main admission causes were physical assault (39.8%), falls (20.5%), and road traffic collisions (10.8%); 69.9% were triaged as very urgent. Only 29.2% were identified before discharge; time as unidentified ranged from 0 to 411 days (median 1 day). Remaining unidentified beyond one day was strongly associated with adverse outcomes (odds ratio 8.56; 95% confidence interval 5.0-14.6; p < .001).

Delayed identification was associated with adverse outcomes, but causality cannot be inferred. Early identification initiatives should be combined with broader strategies to address underlying risks and ensure continuity of care.