A National Dataset Analysis of older adults in emergency department observation units

Background: Emergency Department (ED) Observation Units (Obs Units) are prevalent in the US, but little is known regarding older adults in observation. Our objective was to describe the Obs Units nationally and observation patients with specific attention to differences in care with increasing age. Design: This is an analysis of 2010–2013 data from the National Hospital Ambulatory Medical Care Survey (NHAMCS), a national observational cohort study including ED patients. Weighted means are presented for continuous data and weighted percent for categorical data. Multivariable logistic regression was used to identify variables associated with placement in and admission from observation. Results: The number of adult ED visits varied from 100 million to 107 million per year and 2.3% of patients were placed in observation. Adults ≥65 years old made up a disproportionate number of Obs Unit patients, 30.6%, compared to only 19.7% of total ED visits (odds ratio 1.5 (95% CI 1.5–1.6), adjusting for sex, race, month, day of week, payer source, and hospital region). The overall admission rate from observation was 35.6%, ranging from 31.3% for ages 18–64 years to 47.5% for adults ≥85 years old (p < 0.001). General symptoms (e.g., nausea, dizziness) and hypertensive disease were the most common diagnoses overall. Older adults varied from younger adults in that they were frequently observed for diseases of the urinary system (ICD-9 590-599) and metabolic disorders (ICD-9 270-279). Conclusions: Older adults are more likely to be cared for in Obs Units. Older adults are treated for different medical conditions than younger adults.