Canadian Headache Society criteria for the diagnosis of acute migraine headache in the ED--do our patients meet these criteria?

Introduction: We previously reported that many patients who present to the ED with "migraine" headache do not meet the International Headache Society criteria (IHSC) for the diagnosis of acute migraine. Objective The aim of the study was to compare the frequency for which ED patients with migraine headache meet the Canadian Headache Society criteria (CHSC) vs the IHSC.
Methods: This was a prospective, observational study, performed at a community ED. Consecutive patients who presented to study authors with a chief complaint of headache were enrolled. Historical/clinical data were collected on a standardized form. Ninety-five percent confidence intervals (95% CIs) were calculated and Fisher exact test was used as appropriate.
Results: One hundred eighty-nine patients were enrolled in this study. Mean age was 38 years. Females comprised 69% of patients. Thirty-seven percent of patients had prior ED visits for headaches. A positive family history of migraines was present in 35% of patients. Diagnostic imaging was previously performed in 44 of the enrollees to evaluate the cause of their headaches. A total of 43 (23%) patients had a prior diagnosis of migraine. Overall CHSC was met in 18% of patients, compared with 15% of patients who met IHSC. Discharge diagnosis of migraine was made in 41% of patients. Of these patients, 33% met CHSC and 28% met IHSC (P=.30). For patients with discharge diagnosis of migraine, 33% of females and 36% of males fit CHSC (P=.53), whereas 26% and 36% met IHSC (P=.34), respectively. For patients with a prior diagnosis of migraine, 32% met CHSC and 26% met IHSC (P=.24). Patients with a prior diagnosis of migraine and/or a discharge diagnosis of migraine met CHSC 31% (95% CI, 22%-40%) of the time vs 25% for the IHSC (95% CI, 16%-34%) (P=.26). Four patients without a discharge and/or previous diagnosis of migraine met CHSC; 3 met IHSC.
Conclusions: In our study population, only a minority of patients with headache who have prior diagnosis and/or ED diagnosis of migraine headache met CHSC. The utility of CHSC and/or IHSC to standardize ED patients for headache research may be limited.