Effect of impairment on health-related quality of life in people with multiple sclerosis: association of functional systems and EQ-5D-5L index values in a cross-sectional study

IntroductionMultiple sclerosis (MS) results in physical and cognitive impairments that negatively affect health-related quality of life (HRQoL). It is unknown to what extent the impact of MS-related impairments on HRQoL are reflected in the association of Expanded Disability Status Scale (EDSS) Functional Systems (FS) scores and EQ-5D-5L index values.MethodsThis cross-sectional, single-center cohort study recruited people with MS (pwMS) attending an outpatient clinic at a German university hospital. Impairment was assessed via FS scores during routine visits. HRQoL was measured with EQ-5D-5L index values. The association of each FS score with EQ-5D-5L index values and the additive effect of all FS on EQ-5D-5L index values was modeled with multivariate linear regression (MLR).ResultsAnalyzing 115 participants, unadjusted MLR of single FS revealed that brainstem, pyramidal, cerebellar, sensory, and cerebral/cognitive dysfunctions were significantly associated with lower HRQoL. In MLR of all FS adjusted for covariates, a one standard deviation decrease in cognitive function was significantly associated with a 6% reduction in HRQoL.ConclusionDysfunctions in FS contribute to a decrease in HRQoL. Cognitive dysfunction was identified to maintain negative association with HRQoL after adjustment for covariates, and routinely assessed FS scores appeared useful indicators to identify pwMS who may benefit from comprehensive cognitive evaluations. This study adds to the growing body of evidence emphasizing the crucial role of cognitive function in HRQoL of pwMS and highlights the need for effective screening and therapeutic strategies.