Health state utilities for migraine based on attack frequency: a time trade-off study

This study aims to evaluate health state utilities for migraine based on attack frequency from a mixed population sample consisting of migraineurs and non-migraineurs. A cross-sectional questionnaire survey was designed to measure health-related quality of life (HRQOL) in migraine without aura by time trade-off method (TTO). A convenience sample of university students and staff was recruited regardless of having ever experienced migraine or not. Subjects were asked to elicit two hypothetical health states characterised by different migraine frequencies ('m': two migraines lasting 4 h each month and 'w': each week) within two hypothetical lifetime frames (20 years left to live/lives until the age of 80 years). Utilities were calculated for the four tasks (U20m, U80m, U20w, U20w) and compared amongst subgroups. Overall 180 respondents were included in the analysis. Mean age was 25.6 years (SD 6.4), 128 (71%) were female and 110 (61%) were self-reported migraineurs. Mean utilities for two migraines each month were U20m = 0.84 (SD 0.26) and U80m = 0.89 (SD 0.14), and for each week were U20w = 0.79 (SD 0.27) and U80w = 0.83 (SD 0.17), respectively. Self-reported migraineurs and females attached higher mean utilities for U80m and older respondents for U20m, respectively (p < 0.05). To our knowledge, this is the first study that provides HRQOL results measured by TTO methodology for migraine. Utility loss ranged from 0.1 to 0.2 depending on attack frequency. HRQOL impairment of having two migraine attacks per week was found similar to living with low back pain (0.77-0.79).