Characteristics of patients who visited emergency departments for headache in South Korea: A descriptive cross-sectional study

Objective: This study aimed to describe the characteristics of adult patients who visit emergency departments (EDs) for non-traumatic headache in South Korea.Background: Little is known about East Asian patients who visit EDs for headache.Methods: This observational, descriptive, cross-sectional study retrospectively analyzed 2019 National Emergency Department Information System data, including age, sex, co-occurring fever, symptom duration, insurance type, transportation mode, ED level, triage level, ED visit time, specialist consultations at the ED, disposition from the ED, and outcomes. The proportion of patients with a life-threatening secondary headache and the diagnostic codes were investigated.Results: A total of 227,288 patients were observed in this study, accounting for 2.2% (227,288/10,238,360) of all ED visits. Females (63.1%; 143,493/227,288) visited EDs more than males, and patients aged 50-60 years (21.0%; 47,637/227,288) visited most frequently. A total of 61.5% (93,789/151,494) of ED visits were within 24 h after headache onset, and 57.6% (131,056/227,288) of visits were assigned to non-urgent triage levels. The most frequent discharge codes were "R51: Headache (not better specified)" from the ED and ward, and "I60: Subarachnoid hemorrhage" from the intensive care unit. The rate of migraine diagnosis was 7.2% (16,471/227,288). A total of 3.1% (7153/227,288) of patients were diagnosed with life-threatening secondary headaches, most commonly subarachnoid hemorrhage (1.2%; 2744/227,288) and cerebral infarction (0.6%; 1341/227,288).Conclusions: In South Korea, the characteristics of patients who visited the ED for non-traumatic headache were not very different from those in existing studies; however, patients tended to visit EDs early and be classified as non-urgent, and emergency physicians tended to enter the diagnosis code "R51: Headache (not better specified)", resulting in a much lower rate of migraine diagnoses. Non-urgent early visitors coded with "R51" may include those who have not yet been diagnosed with primary headache and have not been treated, but who need further research.