Objective.—To provide a multidimensional assessment of the extent of functional impairment during an acute migraine attack, and of the improvement in functioning in response to treatment, using 4 concurrently administered scales: the 7-item work productivity questionnaire (PQ-7), the functional assessment in migraine (FAIM) activities and participation (FAIM-A&P) subscale, the FAIM-impact of migraine on mental functioning (FAIM-IMMF) subscale, and the traditional 4-point global functional impairment scale (FIS).
Methods.—Outpatients with an International Classification of Headache Disorders diagnosis of migraine were randomized to double-blind treatment of a single attack with either oral eletriptan 20 mg (n = 192) once-daily, eletriptan 40 mg (N = 213) once-daily, or placebo (n = 208). Patients were encouraged to take study medication as soon as they were sure they were experiencing a typical migraine headache, after the aura phase (if present) had ended. Patients with moderate-to-severe functional impairment were identified on each of the 4 disability scales, and 2-hour functional response was compared between treatments.
Results.—At baseline, the PQ-7 and FAIM-IMMF items that assessed ability to perform tasks requiring concentration, sustained work or attention, and ability to think quickly or spontaneously, were especially sensitive to the effects of mild headache pain, with 27% to 48% of patients (n = 92-112) reporting moderate-to-severe impairment. Only 11.3% of patients (n = 112) reported this level of impairment due to mild pain on the FIS. Functional response at 2 hours was significantly higher on eletriptan 40 mg versus placebo on the FAIM-A&P (63% vs 36%; n = 218; P < .0001); on the PQ-7 (56% vs 34%; n = 116; P= .0052); and on the FAIM-IMMF (50% vs 34%; n = 215; P= .017). These rates were all lower than the functional response rates on the FIS for eletriptan 40 mg (75%) and eletriptan 20 mg (70%) versus placebo (45%; P < .001).
Conclusions.—In this exploratory analysis, use of multidimensional scales was found to provide a sensitive measure of headache-related functional impairment, especially for detecting clinically meaningful cognitive effects, and for detecting drug versus placebo differences.