To describe differences in within-person patterns of cardinal migraine-associated symptoms across the phases of the migraine cycle.
Cardinal migraine-associated symptoms can impose significant disability and are a central focus of clinical care and research, but little is known about how they unfold across the full migraine cycle from the patient perspective. As a part of the Migraine Clinical Outcome Assessment System (MiCOAS) project, qualitative interviews were undertaken to elicit a description of symptom occurrence by migraine phase. We applied a novel analytic framework to these data to examine within-person patterns of migraine-related symptoms.
Forty individuals with self-reported, medically diagnosed migraine were screened to confirm diagnosis before participating in semi-structured interviews. Interviews explicitly probed symptoms by headache phase using standardized open-ended questions. Responses were transcribed and coded using content and thematic analysis methods. Within-person patterns of symptom endorsement were described across migraine phases (pre-headache, headache, post-headache, interictal) for specific cardinal symptoms (nausea/vomiting, photophobia, and phonophobia) using descriptive statistics (n, %) and innovative conditional branching pattern analyses with tree diagrams.
Participants were 77.5% female and 67.5% white with an average age of 44. Participants varied greatly in their specific within-person symptom patterns across phases. Although results showed that the most common pattern entailed symptoms exclusively occurring during both pre-headache and headache phases, this pattern applied to a minority of individuals (nausea/vomiting: 27.5%[n=11]; photophobia: 40%[n=16]; phonophobia 27.5%[n=11]). Symptoms were regularly reported in the pre-headache phase without being endorsed in the headache phase (nausea/vomiting: 17.5%[n=7]; photophobia: 12.5%[n=5]; phonophobia 20.0%[n=8]).
There were common within-person patterns of symptom endorsement across phases that may support potential patient phenotypes. However, results also suggested heterogeneity in the patient experience and potential shortcomings of focusing solely on the headache phase. Findings highlight the importance of leveraging patient-centered research to better inform clinical practice and research.