Baseline characteristics of the first patients included in the OFSEP high definition cohort and relationship between quality of life and patients' characteristics

International audienceContext: The OFSEP registry in multiple sclerosis (MS) recently proposed a high-definition (HD) cohort to better appreciate the causal factors of disease progression and develop reliable predictive tools to help in medical decision making and informing patients at different key moments in the disease course.Objectives: To describe the characteristics of the first patients included in the HD cohort and to analyse their cross-sectional relationship with quality of life (QoL) measures.Methods: MS patients are followed annually. Data collection includes OFSEP core minimal clinical data, MFSC, brain MRI, comorbidities, serum biomarkers and patient-reported outcomes including QoL. Inclusions in the HD cohort started in July 2018. Patients were described according to demographic, clinical and therapeutic characteristics at inclusion. Several QoL indicators were available: the visual analogue scale (VAS) of the EQ5D-5L, the physical (PCS) and mental (MCS) component summary scores of the SF12, and the summary index of the MuSiQoL. Associations between patients’ characteristics and QoL indicators were analysed with multiple linear regression (p< 0.05 was considered as significant).Results: In March 2019, 621 patients were included, mainly women (73%), with an age at inclusion of 43±11 years and disease duration of 12±9 years. Disease course was relapsing-remitting (80%), secondary (12%) and primary progressive (8%). Majority of patients had a low disability (EDSS [0-2.5], 57%; [3-3.5], 12%; [4-5.5], 18.2%; [6-7], 13%). Twenty two percent were untreated; others were mainly treated with natalizumab (22%), fingolimod (14%) and rituximab (10%). In multivariate analysis, VAS was significantly lower in patients with progressive course and high levels of EDSS. The same correlations were observed for the PCS, which was additionally higher in first line treated patients. Regarding the MusiQoL, its level was significantly lower in patients with high levels of EDSS. In contrast, MCS was higher for EDSS [0-2.5] and lower for [4-5.5].Discussion: The first patients included in the HD cohort had a low disability and were mostly treated with second line drugs. A low QoL was associated to higher EDSS but not to disease activity; clinical course and treatment were associated with some scales but not for others. The relationship observed between QoL and disability validates the usefulness of the QoL collection of data in the perspective of a patient-centred research program