Abstract
Background Migraine is a neurological disease involving recurrent attacks of moderate-to-severe and disabling head pain. Worsening of pain with routine physical activity during attacks is a principal migraine symptom; however, the frequency, individual consistency, and correlates of this symptom are unknown. Given the potential of this symptom to undermine participation in daily physical activity, an effective migraine prevention strategy, further research is warranted. This study is the first to prospectively evaluate (a) frequency and individual consistency of physical activity-related pain worsening during migraine attacks, and (b) potential correlates, including other migraine symptoms, anthropometric characteristics, psychological symptoms, and daily physical activity. Methods Participants were women (n = 132) aged 18-50 years with neurologist-confirmed migraine and overweight/obesity seeking weight loss treatment in the Women's Health and Migraine trial. At baseline, participants used a smartphone diary to record migraine attack occurrence, severity, and symptoms for 28 days. Participants also completed questionnaires and 7 days of objective physical activity monitoring before and after diary completion, respectively. Patterning of the effect of physical activity on pain was summarized within-subject by calculating the proportion (%) of attacks in which physical activity worsened, improved, or had no effect on pain. Results Participants reported 5.5 ± 2.8 (mean ± standard deviation) migraine attacks over 28 days. The intraclass correlation (coefficient = 0.71) indicated high consistency in participants' reports of activity-related pain worsening or not. On average, activity worsened pain in 34.8 ± 35.6% of attacks, had no effect on pain in 61.8 ± 34.6% of attacks and improved pain in 3.4 ± 12.7% of attacks. Few participants (9.8%) reported activity-related pain worsening in all attacks. A higher percentage of attacks where physical activity worsened pain demonstrated small-sized correlations with more severe nausea, photophobia, phonophobia, and allodynia (r = 0.18 - 0.22, p < 0.05). Pain worsening due to physical activity was not related to psychological symptoms or total daily physical activity. Conclusions There is large variability in the effect of physical activity on pain during migraine attacks that can be accounted for by individual differences. For a minority of participants, physical activity consistently contributed to pain worsening. More frequent physical activity-related pain worsening was related to greater severity of other migraine symptoms and pain sensitivity, which supports the validity of this diagnostic feature. Study protocol ClinicalTrials.govIdentifier: NCT01197196.