Background: Studies have reported an association between socioeconomic status and disability progression in multiple sclerosis (MS), but findings using the pre-MS individual socioeconomic status are missing.
Objective: The objective was to investigate the association between education level and disability progression.
Methods: All Observatoire Français de la Sclérose en Plaques (OFSEP) patients with MS clinical onset over 1960-2014, and aged ⩾25 years at MS onset were included. Education level was classified into four categories from low (primary/secondary school) to very high (master/doctoral degree). Time from MS onset to EDSS 4.0 was studied using flexible parametric survival models adjusted for age, period, and center, and stratified by phenotype (relapsing multiple sclerosis (RMS) and primary progressive multiple sclerosis (PPMS)) and sex.
Results: A total of 11,586 patients were included (women/men ratio = 2.5; age = 36.7 ± 8.6 years; follow-up duration 16.7 ± 9.3 years; 86.4% RMS). For women with RMS, the risk of reaching the outcome at 5 years was inversely associated with the education level (Hazard Ratio medium: 0.74 (0.63-0.87), high: 0.51 (0.43-0.62), very high: 0.39 (0.30-0.50) vs low). Results were similar for men. In PPMS, the risk was significantly different between the extreme groups (very high vs low) for women (0.45 (0.28-0.75)) and men (0.54 (0.32-0.91)), but no gradient was evident.
Conclusion: Our study showed a strong association between education level and disability progression, regardless of sex and phenotype.
Keywords: Multiple sclerosis; disability progression; observational study; social inequities.