Changes in Neurologic Disability and Health-Related Quality of Life Utility Over 8 Years in Patients with Multiple Sclerosis (P1.389)

Background: Understanding the effectiveness and cost-effectiveness of MS treatments requires better evidence of the relation between changes in neurological disability and changes on utility measures of patient-reported health-related quality of life (HRQoL). The Expanded Disability Status Scale (EDSS) remains the primary measure of MS-related neurologic disability. The Health Utilities Index Mark III (HUI3) is a validated HRQoL utility measure for MS patients. Objective: To evaluate the impact of changes in EDSS on the HUI3 in a representative clinic-attending MS sample over 8 years. Methods: From 2006-2014, the EDSS and HUI3 were collected for 2,036 patients attending the Dalhousie MS Research Unit; the sole MS care clinic and provider of disease-modifying therapies in Nova Scotia, Canada. A series of multilevel growth curve models examined changes in HUI3 in relation to changes in EDSS, controlling for sex, age, and education. EDSS scores were examined in raw form and with various EDSS endpoints. Relapsing-remitting (RRMS) and secondary-progressive (SPMS) patients were modeled separately. Results: We examined 11098 visits. At baseline assessment, 77[percnt] of the sample was female; average age was 46 years. On average, HUI3 declined 0.3[percnt] in RRMS patients and 0.6[percnt] in SPMS per year. Baseline EDSS and age were associated with lower HUI3 (p < 0.001). Within-person increases in EDSS by 1 point were associated with significant decreases in HUI3 (RRMS: 2.2[percnt], SPMS: 7.6[percnt]). Separate models examining EDSS endpoints indicated that reaching specific disability endpoints had a large impact on HUI3. For example, for RRMS patients, reaching EDSS 6 during the period of observation was associated with a 20[percnt] decline in HUI3; for SPMS this decline was 14[percnt]. Conclusions: Our findings illustrate that if MS treatments can delay disability progression they have the potential to substantially impact HRQoL utility. Such data are necessary for comparative cost-effectiveness analyses and resource allocation policies. Disclosure: Dr. Fisk has nothing to disclose. Dr. Armstrong has received research support from Canadian Consortium on Neurodegeneration in Ageing. Dr. Bhan has received personal compensation from Biogen Idec, EMD Serono, Genzyme, Novartis, Roche and Teva. Dr. Trudy Lorraine Campbell has received personal compensation for activities with Biogen Idec Canada, Teva Canada Innovation, EMD Serono, Genzyme, and Novartis as a traveler. Dr. Stadnyk has nothing to disclose. Dr. Marrie has received research support from the Canadian Institutes of Health Research, Multiple Sclerosis Society of Canada, National Multiple Sclerosis Society, Rx & D Health Research Foundation, Research Manitoba and sanofi-aventis.