Background While pain intensity during migraine headache attacks is known to be a determinant of interference with daily activities, no study has evaluated: (a) the pain intensity-interference association in real-time on a per-headache basis, (b) multiple interference domains, and (c) factors that modify the association. Methods Participants were 116 women with overweight/obesity and migraine seeking behavioral treatment to lose weight and decrease headaches in the Women's Health and Migraine trial. Ecological momentary assessment, via smartphone-based 28-day headache diary, and linear mixed-effects models were used to study associations between pain intensity and total- and domain-specific interference scores using the Brief Pain Inventory. Multiple factors (e.g. pain catastrophizing (PC) and headache management self-efficacy (HMSE)) were evaluated either as independent predictors or moderators of the pain intensity-interference relationship. Results Pain intensity predicted degree of pain interference across all domains either as a main effect (coeff = 0.61-0.78, p < 0.001) or interaction with PC, allodynia, and HMSE ( p < 0.05). Older age and greater allodynia consistently predicted higher interference, regardless of pain intensity (coeff = 0.04-0.19, p < 0.05). Conclusions Pain intensity is a consistent predictor of pain interference on migraine headache days. Allodynia, PC, and HMSE moderated the pain intensity-interference relationship, and may be promising targets for interventions to reduce pain interference.
Keywords: Migraine; ecological momentary assessment; obesity; pain intensity; pain interference.