Physician adherence to anaphylaxis guidelines among different age groups in emergency departments: 20-Year observational study.

Background: Anaphylaxis is an acute and serious allergic reaction. Little is known about physician adherence to anaphylaxis guidelines among patients across different age groups.

Objective: To investigate real-world physician adherence to anaphylaxis guidelines among children, adults, and older adults in emergency departments.

Methods: This study retrospectively analyzed all consecutive patients with anaphylaxis who presented to 2 emergency departments at 2 branches of the largest tertiary hospital in Taiwan, between 2001 and 2020. Patients who met the diagnostic criteria for anaphylaxis were enrolled and grouped by age: children (<18 years), adults (18-64 years), and older adults (≥65 years).

Results: We enrolled 771 patients with anaphylaxis (159 children, 498 adults, and 114 older adults). Intramuscular epinephrine was administered in 294 cases (38.1%). There was a significant age-group difference in the rate of intramuscular epinephrine administration (46.5% in children, 37.3% in adults, and 29.8% in older adults; P trend = .004). When stratified by severity, 14.3% of older adults with moderate reactions received intramuscular epinephrine, whereas 35.2% of adults and 55.3% of children received intramuscular epinephrine (P trend < .001), whereas such difference was not found in patients with severe reactions. Upon discharge from emergency departments, 15.3% received allergist referral (52.2% in children, 6.6% in adults, and 1.8% in older adults; P trend < .001); 12.5% received education on avoidance of triggers (18.9%, 11.4%, and 7.9%; P trend = .01), and 16.1% received education on alarm symptoms (21.4%, 15.1%, and 13.2%; P trend = .05).

Conclusion: The real-world physician adherence to anaphylaxis guidelines remains suboptimal in emergency departments, particularly among older adults. Physician continuing education is needed to improve the gap between anaphylaxis guidelines and clinical practice.