Evaluating the study design and criteria used for status migrainosus research: A systematic review

The goal of this study was to synthesize the evidence on how "status migrainosus" is defined in research studies in comparison to established International Classification of Headache Disorders (ICHD) criteria.

Current ICHD-3 criteria define status migrainosus as a headache attack occurring in a patient with a history of migraine with or without aura that is typical of previous attacks except for its duration (>72 h) and severity (debilitating). Despite the ICHD criteria, there are varying inclusion criteria noted in studies enrolling patients with status migrainosus. With this diagnostic uncertainty, there remains difficulty in studying this patient population.

This systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Ovid MEDLINE, Ovid EMBASE, All Evidence-Based Medicine Reviews, the Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform were searched with the end search date of August 29, 2025. We included studies that were original research focused on status migrainosus, published in English after January 1, 1988, and also included diagnostic criteria to define this condition. The abstracts and full texts were screened by independent reviewers, with a third independent reviewer remaining available to settle disputes. There were 45 studies that underwent full text review, with 19 of these studies included. Data extraction was conducted recording the criteria used to define status migrainosus, headache characteristics, and goals of each study.

We identified four common domains among studies of status migrainosus, including use of ICHD criteria, headache duration, symptom severity, and treatment response. Reference to ICHD criteria was variable, with only 68% (13/19) of studies specifying an edition of ICHD criteria applied in recruiting or studying patients with status migrainosus. The majority of studies (16/19; 84%) used a headache duration greater than 72 h to define status migrainosus. The use of symptom severity with "debilitating" or "severe" was present in 63% (12/19) of studies and depended on the edition of ICHD criteria that was referenced. Treatment response was rarely used as a condition in defining status migrainosus, with only 15% (3/19) of studies utilizing this stipulation in diagnostic criteria.

The results of this systematic review show inconsistent application of ICHD criteria in research studies focusing on status migrainosus. These inconsistencies lead to ambiguity in how status migrainosus is defined in the research setting and limit the ability to replicate or compare studies. Guidelines outlining best practices for research of status migrainosus are necessary. For prospective studies, consistent utilization of ICHD criteria is necessary, with potential need to revise these criteria to better reflect the clinical realities of this entity. For retrospective studies, implementation of a standardized International Classification of Diseases code for status migrainosus would be of benefit to improve diagnostic clarity because the current codes are lengthy, cumbersome, and unclear.