Racial Differences in Neuroimaging Utilization and Secondary Headache Diagnosis in the Emergency Department

Purpose: Headache is among the most common reasons for patients to seek evaluation in the Emergency Department (ED). Growing evidence suggests that neuroimaging decisions may differ across racial and ethnic groups due to systemic and implicit biases in emergency care. This study aimed to evaluate racial differences in neuroimaging utilization by modality among adults presenting to the ED with headache.

Methods/Materials: Using the Medical Information Mart for Intensive Care IV (MIMIC-IV) database, we conducted a retrospective review of adult ED encounters with a chief complaint of headache. Encounters were stratified by self-identified race. Imaging utilization was categorized as no imaging, MRI, CT without contrast, CT with contrast, or CT angiography (CTA). Diagnoses were classified as primary or secondary headaches. We compared imaging patterns and diagnostic outcomes by race using Chi-square analysis, with standardized residuals calculated to determine which groups contributed most to observed differences.

Results: Significant racial variation was observed in both neuroimaging modality and headache diagnosis between races. MRI and CTA imaging were performed at higher rates in white patients (standardized residual +3.45 and +5.25, respectively), who were less likely to receive no imaging (–3.91) compared to other races. In contrast, Black (+3.11) and Hispanic (+2.45) patients were significantly more likely to undergo no imaging and less likely to receive MRI (–2.27 and –3.17, respectively) or CTA (–4.65 and –2.44). When evaluating outcomes, 46.1 % of White, 43.8 % of Hispanic, 44.0 % of Black, 56.2 % of Asian, and 44.1 % of “Other” patients were diagnosed with a secondary cause of headache. The higher rate among Asian patients (P < 0.0001) persisted independent of imaging type.

Conclusions: Significant racial differences were observed in both neuroimaging utilization and diagnoses of secondary headache among ED patients. White patients more often underwent MRI or CTA, whereas Black and Hispanic patients were imaged less frequently despite similar diagnostic yield. Asian patients exhibited the highest rate of secondary headache diagnoses, a difference that persisted across imaging types.