Clinical and sociodemographic factors associated with frequent use of emergency services by persons of advanced age in Paris: a nested case-control study.

Objective: To identify clinical and sociodemographic characteristics of frequent use of emergency departments by persons of advanced age.
Methods: Nested case-control study in a cohort of patients aged 75 years or older attending 3 hospital emergency departments (EDs) in Paris between January 1, 2018, and December 31, 2019. The index date was defined by the last visit during the study period. Frequency was defined as making 4 or more visits to an ED during the year prior to the index date. Controls were patients who visited an ED fewer than 4 times. We first analyzed sociodemographic factors related to frequent use and then randomly selected a convenience sample of 300 patients (150 frequent users and 150 in the non-frequent users) stratified by hospital. In this sample we analyzed clinical factors associated with frequent use. The statistical analysis included multivariate logistical regression models.
Results: A total of 29 009 patients of advanced age visited the 3 EDs; 1241 (4.3%; 95% CI, 4.1%-4.5%) were frequent users in the year prior to their index date. Independent factors associated with frequent visiting were older age (odds ratio [OR], 1.03; 95% CI, 1.02-1.04); male sex (OR, 1.15; 95% CI, 1.02-1.29); the presence of comorbidities, eg, a history of falls (OR, 2.42; 95% CI, 1.27-4.70), stroke (OR, 4.07 (95% CI, 1.84-9.69), or cognitive decline (OR, 2.53; 95% CI, 1.20-5.45); loss of autonomy (OR, 2.70; 95% CI, 1.38-5.41); and medications, eg, diuretics (OR, 2.10; 95% CI, 1.09-4.11) or benzodiazepines (OR, 2.27; 95% CI, 1.07-5.00).
Conclusions: Frail elderly patients with more comorbid conditions are at higher risk for frequent use of emergency departments. These patients should be identified early so that management of their conditions can be adjusted.