Association between Disability, Cognition, Fatigue, EQ-5D-3L Domains, and Utilities Estimated with Different Western European Value Sets in Patients with Multiple Sclerosis.

OBJECTIVES

To assess the association between fatigue, cognition, domains of the EuroQol five-dimensional questionnaire (EQ-5D-3L), disability, and utilities estimated with several Western European value sets in patients with multiple sclerosis (MS).

METHODS

Data from a multinational, cross-sectional, observational study of patients with MS (N = 16,808) conducted in 16 European countries were used. Health-related quality of life data were collected through the EQ-5D-3L, and fatigue and cognitive difficulties were self-assessed on a 10-point visual analogue scale. Associations were assessed using Pearson correlation and multivariate regression model.

RESULTS

Symptoms of fatigue and cognitive difficulties were present in 90% and 70% of patients at all levels of disability, respectively, and thus only weakly correlated to disability. Problems in the EQ-5D-3L domains were common even at mild disability levels. Mobility, usual activities, and pain issues were experienced by 80% to 90% of patients with moderate and high levels of disability. Mobility, usual activities, and self-care were strongly correlated to disability. Disability, MS type, fatigue, and cognition were associated with utility in regression models, although the coefficients of fatigue and cognition were small.

CONCLUSIONS

The strong relationship of disability with utility was confirmed. Despite this, fatigue and cognitive difficulties were associated with utility estimated with different European value sets.