Anaphylaxis in emergency department patients 50 or 65 years or older

Anaphylaxis is a potentially life-threatening allergic reaction commonly managed in the emergency department (ED). Data describing patients 50 or 65 years or older with anaphylaxis are limited.

To describe the presentation and management of patients with anaphylaxis who were 50 or 65 years or older and to compare these findings with those of younger patients.

A consecutive cohort study of patients presenting to an ED with approximately 80,000 visits per year was conducted. Patients who met diagnostic criteria for anaphylaxis from April 2008 to June 2010 were included. Data were collected on suspected causes, signs and symptoms, management, ED disposition, and follow-up.

The study included 220 patients. Food was the most common suspected cause of anaphylaxis for patients younger than 50 (42.2%) or 65 years (38.5%) but was much less common in patients 50 (14.8%, P < .001) or 65 years or older (14.3%, P = .01). Cardiovascular symptoms were more likely to occur in older patients (≥50 years old, 55.6% vs 30.1%, P < .001; ≥65 years old, 64.3% vs 32.3%, P = .002). Patients 50 or 65 years or older were less likely to be dismissed home directly from the ED (≥50 years old, 35.2% vs 56.6%, P = .006; ≥65 years old, 32.1% vs 54.2%, P = .03) and were less likely to be prescribed self-injectable epinephrine (≥50 years old, 40.7% vs 63.3%, P = .004; ≥65 years old, 32.1% vs 61.5%, P = .003).

In ED patients presenting with anaphylaxis, age of 50 or 65 years or older is associated with a decreased likelihood of food-induced anaphylaxis, increased likelihood of experiencing cardiovascular symptoms, decreased dismissal to home directly from the ED, and decreased prescriptions for self-injectable epinephrine.