Improvement of quality of life and its relationship with neuropsychiatric outcomes in patients with multiple sclerosis starting treatment with natalizumab: A 3-year follow-up multicentric study

Background: Health-related quality of life (HRQoL) is impaired in multiple sclerosis (MS) but can be improved by disease-modifying therapies such as natalizumab. However, the predictive factors and neuropsychiatric correlates of HRQoL improvement are unknown. Methods: In this study, 48 patients with relapsing-remitting MS were included in a 3-year open-label, single group, multicenter, clinical trial (NCT01392872). HRQoL was measured by the disease-specific MusiQoL questionnaire, together with physical disability, cognition, fatigue, anxiety and depression scores at baseline, 6 months, 12 months, 18 months and 36 months after starting natalizumab therapy. Results: Compared to baseline, global HRQoL, as measured with the index of the MusiQoL, was significantly increased 6 months after the beginning of natalizumab therapy, with medium effect-size (58.6 +/- 16.2 vs 69.8 +/- 18.9, p < 0.001, Cohen's d = 0.63). This improvement was maintained over time for up to 3 years and mainly concerned activity of daily living, psychological well-being, symptoms and coping (p < 0.001 for every dimensions). The variation of global HRQoL after 3 years was negatively correlated with the variation of fatigue score (r = 0.44, p = 0.015). Furthermore, a higher fatigue score at baseline was correlated with improvement in global HRQoL 3 years afterwards (r = 0.34, p = 0.041), independently of age, educational level, disease duration and disability at baseline (beta = 2.45, p = 0.020). Disability at baseline, cognitive impairment, anxiety and depression failed to predict or correlate with global HRQoL improvement in multivariate analyses. Conclusion: Natalizumab improved HRQoL quickly and sustainably in patients with relapsing-remitting MS. In terms of HRQoL, natalizumab seems to benefit mostly patients with more marked fatigue at baseline.