Does health-related quality of life differ between people with relapse onset and progressive onset Multiple Sclerosis?

Background: Multiple Sclerosis (MS) can be categorised as relapse onset MS (ROMS) and progressive onset MS (PROMS). We aimed to examine if health-related quality of life (in terms of health state utilities [HSUs] and dimensional scores) differed by onset type, in which health dimensions the differences were most pronounced, and whether these differences remained when stratified by disability severity. Methods: We estimated HSUs and the unique composite 'super-dimension' and 'individual dimension' scores (crude, age, sex, disease duration and disease modifying therapies use adjusted; and stratified by onset type and disability severity) for a sample of 1577 participants in the Australian MS Longitudinal Study, using the Assessment of Quality of Life (AQoL)-8D. Results: Adjusted mean overall HSU of PROMS was 0.55, 0.07 lower than ROMS. Adjusted mean physical and psychosocial super-dimension scores for PROMS were 0.51 and 0.28, 0.07 and 0.06 lower than for ROMS, respectively. For the individual health dimensions, the largest difference was seen in independent living (-0.12), followed by relationships (-0.07), and self-worth (-0.07). Whilst HSUs and dimensional scores were negatively associated with increasing disability severity in both onset types, estimates by disability severity did not differ between the two cohorts. Conclusions: Our study provides a comprehensive assessment of the effects of MS onset type on the overall and disability-severity specific HRQoL scores using a detailed preferentially sensitive AQoL-8D instrument. While overall HRQoL was substantially lower in PROMS than in ROMS, the mean HRQoL values for each disability level did not differ by onset type, indicating that future health economic models can use the same HSU inputs for both onset types.