Acute Headache Management and Emergency Department Throughput: A Multicenter Retrospective Analysis

Headache is a common presentation to the emergency department (ED), requiring both accurate diagnosis and efficient management. Although consensus guidelines exist, real-world treatment practices and their associations with operational outcomes remain variable. We evaluated the association between acute headache management strategies-including medications, diagnostic imaging, and consultations-and ED length of stay (LOS), using both unadjusted and multivariable-adjusted analyses.

We conducted a multicenter retrospective observational study using data from 79,527 adult ED encounters for headache across 22 EDs in the southwestern and upper Midwestern United States between 2018 and 2024. The primary outcome was ED LOS. Secondary outcomes included LOS differences associated with medication classes, imaging modalities, procedures, and specialty consultations. Length of stay differences by treatment strategy were compared using Mann-Whitney U testing. We performed multivariable linear regression and quantile regression (median) adjusting for age, sex, Emergency Severity Index level, disposition, imaging, procedures, consultations, site, and year. Encounters were classified by headache type (primary, secondary, or unspecified) using discharge diagnosis codes, and stratified analyses were performed.

Primary headache encounters comprised 19.4% of the cohort (n = 15,413), secondary headache 14.0% (n = 11,147), and unspecified headache 66.6% (n = 52,967). The overall median LOS was 183 minutes (interquartile range [IQR], 119-276). In unadjusted analyses, nonsteroidal anti-inflammatory drug (NSAID) (median 180 vs 185 minutes; P = .42) and triptan administration (177 vs 183 minutes; P = .49) were not associated with longer LOS. In contrast, antiseizure medications (+136 minutes; P < .001), intravenous magnesium (+101 minutes; P < .001), opioids (+89 minutes; P < .001), and benzodiazepines (+72 minutes; P < .001) were associated with the longest LOS. In multivariable-adjusted analysis (R² = .40), antiseizure medications (adjusted coefficient +85.1 min; 95% CI, 76.0-94.3), admission (+71.1 minutes; 95% CI, 68.3-73.8), and magnetic resonance imaging (+125.9 minutes; 95% CI, 119.8-131.9) were most strongly associated with longer LOS. Stratified analyses showed primary headaches had shorter median LOS (153 minutes; IQR, 105-224) than secondary (204 minutes; IQR, 126-317) or unspecified headaches (189 minutes; IQR, 123-282), with consistent medication-LOS associations across subgroups (Kruskal-Wallis H = 1,476.85, P < .001; all pairwise comparisons P < .001 after Bonferroni correction).

In this multicenter retrospective study, most pharmacologic and diagnostic interventions-aside from NSAIDs and triptans-were associated with longer ED LOS, even after adjusting for patient and clinical covariates. These associations likely reflect both direct treatment effects and confounding by indication. Prospective studies are needed to evaluate whether standardized protocols can improve ED throughput while maintaining care quality.