Measuring the health-related quality of life in Australians with multiple sclerosis using the assessment of quality of life-8-dimension (AQoL-8D) multi-attribute utility instrument

Abstract

Background: Health-related quality of life (HRQoL) has not been assessed in Australians with multiple sclerosis (MS) using a preferentially sensitive multi-attribute utility instrument.

Objectives: To assess HRQoL and to quantify the impact of disability on health state utility values (HSUVs), and the physical and psychosocial health of people with MS using the Assessment of Quality of Life-8-Dimension (AQoL-8D) instrument.

Methods: We estimated HSUVs and the unique composite individual and super dimensional (physical and psychosocial) scores of the AQoL-8D for a large, representative sample (n=1,577) of Australians with MS. The estimates were compared to Australian general population norms and broken down by disability severity, classified as no disability (Expanded Disability Status Scale [EDSS] level: 0), mild (EDSS: 1-3.5), moderate (EDSS: 4-6) and severe (EDSS: 6.5-9.5). A multivariable regression model adjusted the association between MS disability severity and HSUVs for age, sex, MS onset type, DMTs usage status, and MS duration.

Results: Mean overall HSUV at 0.61 (95% confidence interval [CI]: 0.60-0.62) was 0.18 units lower than the Australian population norm. HSUV decreased with increasing disability severity: 0.81 (95% CI: 0.80-0.83), 0.65 (95% CI: 0.63-0.67), 0.54 (95% CI: 0.52-0.56) and 0.48 (95% CI: 0.46-0.50) for no, mild, moderate and severe disability, respectively. The mean Physical super-dimension score of 0.57 (95% CI: 56-0.58) was 0.21 units lower than the Australian norm and the Psychosocial super-dimension of 0.33(95% CI: 32-0.34) was 0.16 units lower. Lower HRQoL was primarily driven by reduced scores on Independent living (-0.23), Pain (-0.15), Relationships (-0.13), Coping (-0.12), and Self-worth (-0.12).

Conclusions: MS impacts all aspects of HRQoL. Effective pain management and support to maintain independent living, relationships, and self-worth can significantly improve the HRQoL of people with MS. Early diagnosis and affordable access to effective treatments to slow or prevent disability accumulation may also be helpful.

Keywords: AQoL-8D; Health state utility values (HSUVs); Health-related quality of life (HRQoL); Multiple sclerosis; Patient-reported outcomes.