Key concepts of migraine postdrome: a qualitative study to develop a post-migraine questionnaire.
OBJECTIVE
To understand migraine postdrome by directly interviewing migraine patients with postdrome symptoms. To document these symptoms, as well as impacts, as a prelude to developing a postdrome migraine questionnaire.


BACKGROUND
Migraine attacks are traditionally divided into 4 phases. Of these, the postdrome is the least studied, and no patient-reported outcomes to assess symptoms and impacts of this migraine phase have been published.


METHODS
Qualitative concept elicitation focus groups were conducted with 34 patients in 3 geographically diverse US cities to elicit the symptoms and burden of migraine postdrome. Data elicited from focus groups were coded using Atlas.ti software to facilitate identification of concepts and terminologies of migraine postdrome. A draft questionnaire was developed based on the symptoms and impacts of migraine postdrome described by patients. Cognitive debriefing interviews were conducted with 15 patients in Connecticut and Chicago to confirm content validity, relevance, and comprehension.


RESULTS
Patients defined the onset of postdrome as when they no longer experienced the migraine pain. Postdrome was often described as "[being] or [feeling] wiped out" and "headache hangover." The symptoms most frequently reported by the patients who participated in the focus groups and included in the draft post-migraine questionnaire were: tiredness, difficulty concentrating, weakness, dizziness, lightheadedness, and decreased energy. Patients also reported decreased activity level as a result of experiencing postdrome symptoms. Postdrome symptoms were reported to impact the ability to work, to affect family interactions and social life, and to cause cognitive impairment. A preliminary questionnaire measuring severity and duration of symptoms and severity of impacts of the post-migraine experience, with an 11-point (0 to 10) response scale, was developed. This preliminary questionnaire was tested for content validity, relevance, and comprehension using cognitive debriefing interviews. All patients reported that the questionnaire was relevant to their condition. Irrelevant and redundant items such as body tension and annoyance were eliminated.


CONCLUSIONS
Migraine postdrome is debilitating for those who experience it. Concept elicitation and cognitive debriefing research support the relevance of the items in the post-migraine questionnaire. Future research will provide evidence of the post-migraine questionnaire's psychometric properties and interpretation guidelines.