Epidemiology, clinical profile, and outcomes of older patients with active cancer attending at Spanish emergency departments (EDEN-56 study)

BACKGROUND: Older adults with active cancer are increasing, clinically complex emergency department (ED) population, but large multicenter European data are limited. OBJECTIVE: To describe the epidemiology, baseline characteristics, diagnoses, and outcomes of older patients with active cancer attending Spanish EDs, and assess whether associations between active cancer and short-term outcomes varied with age and sex. DESIGN, SETTING, AND PARTICIPANTS: Secondary analysis of the Emergency Department and Elder Needs retrospective multicenter registry, including all patients aged greater than or equal to 65 years attending 52 Spanish EDs during 1-7 April 2019. Patients with and without active cancer were compared. Annualized incidence was extrapolated overall, by sex, and by age. Age-related patterns were modeled using restricted cubic splines. OUTCOME AND ANALYSIS: ED length of stay, hospitalization, length of hospitalization, and index-episode death. Age-by-cancer and age-by-sex interactions were assessed in unadjusted and multivariable models. MAIN RESULTS: Among 25 557 older ED patients, 4701 (18.4%) had active cancer. The estimated annualized incidence of ED presentations was 10 885 per 100 000 inhabitants aged greater than or equal to 65 years [95% confidence interval (CI): 10 576-11 200], higher in men (annualized rate ratio: 1.80, 95% CI: 1.70-1.91) and in the mid-to-late 80s. Patients with cancer had more severe comorbidity (58.9 vs. 12.9%), polypharmacy (26.6 vs. 21.3%), and walking handicaps (31.5 vs. 28.2%). Malignancy accounted for only 7.7% of ED diagnoses in the cancer group; infections, heart failure, and respiratory conditions were frequent. Active cancer was associated with longer median ED stay (4.0 vs. 3.3 h; adjusted difference: 0.3, 95% CI: 0.1-0.4), higher hospitalization [32.5 vs. 24.0%; adjusted odds ratio (OR): 1.34, 95% CI: 1.25-1.44], longer median hospitalization (7.5 vs. 6.9 days; adjusted difference: 0.5, 0.1-0.9), and higher index-episode mortality (5.5 vs. 2.5%; adjusted OR: 2.12, 95% CI: 1.81-2.50). Age significantly modified ED length of stay, hospitalization, and mortality, with significantly different age-related changes between patients with and without cancer. Among patients with cancer, age-related trajectories did not significantly differ by sex. CONCLUSION: Active cancer is common among older ED patients and associated with substantial resource use and worse short-term outcomes. These associations vary with age, supporting multidimensional assessment beyond chronological age or cancer status alone.