Background and Objectives: objective measures of disability and neurological impairmentare used to search for disease activity and monitor disease evolution in multiple sclerosis (MS). These are sometimes in disagreement with subjective quality-of-life measures. We aimed to establish the relations between the Multiple Sclerosis Quality of Life instrument (MSQOL-54) and objective measures of neurological impairment. Materials and Methods: 107 patients with MS were evaluated with the Single Digit Modalities Test (SDMT) for cognition, Nine Holes Peg Test (9HPT) for upper limb function, 25 Feet Walk Test (25FWT) for gait, and EDSS for global disability in a cohort study. Age and education level were recorded as sociodemographic factors. Results: the median EDSS was 3.5 (IQR 2.5); average SDMT score was 30.38 ± 13.54; and 9HPT speed was significantly higher for the dominant upper limb (0.3 ± 0.1 pegs/s versus 0.28 ± 0.11 pegs/s) (p = 0.016). The mental health composite score of the MSQOL-54 correlated with the SDMT, education level, and EDSS. Education level correlated with cognition and quality of life. The physical health composite score of the MSQOL-54 correlated with motor-function parameters and with SDMT. The motor-function parameters correlated well among themselves. A linear regression model found an important influence of SDMT and education level on the mental health composite score of the MSQOL-54. Although the linear regression model predicting the physical health composite score from physical disability parameters was statistically sound, none of the determinants had a significant individual influence. Conclusions: the subscores of the MSQOL-54 correlated well with the objective parameters. The strongest correlations were those with the cognitive function. Correlations with physical disability were less powerful, probably reflecting their indirect and more limited influence on quality of life compared to cognition and perception of disability.
Keywords: 25FWT; 9HPT; MSQOL-54; SDMT; cognition; disability evaluation; education; multiple sclerosis; quality of life; walking speed.