Socioeconomic deprivation increases the risk of disability in multiple sclerosis patients

Background: Little is known about the association between the socioeconomic status (SES) and disability risk of patients with Multiple Sclerosis (MS). Objective: The aim of this study was to assess the influence of low SES, otherwise known as socioeconomic deprivation, on the disability risk of MS patients. Methods: 4498 patients with a relapsing MS disease onset between 1982 and 2017 were included from the databases of three MS expert centres (Caen, Rouen, Lille) of the French Observatory for MS (OFSEP). Sociodemographic and clinical data of 3641 patients were used for the analysis. The EDI (European Deprivation Index), an ecological and composite indicator was used to assess the level of socioeconomic deprivation. Comparisons of time to reach EDSS 4 and EDSS 6, chosen as disability milestones, according to EDI quintiles were performed by Kaplan-Meier analysis. Cox proportional hazard models were also conducted to assess the risk according to EDI quintiles with adjustment to sex, MS type and age at disease onset. Results: In the study population (n = 3641), most patients were women (71.9%; n = 2664). The mean age at disease onset was 32.2 years (SD = 9.7). 1684 (46%) patients reached EDSS 4 and 1005 (28%) reached EDSS 6. The risk of reaching EDSS 4 and EDSS 6 in more socioeconomically deprived patients (EDI Q5) was independently higher than in the less socioeconomically deprived patients (EDI Q1) (HR = 1.37 95%CI [1.15-1.64]) to reach EDSS 4 and (HR = 1.42 95%CI [1.13-1.75]) to reach EDSS 6. Conclusions: In this study, socioeconomic deprivation was significantly associated to the disability risk in MS patients. Better knowledge of socioeconomic disparities in MS may help adapt care to settings and improve the quality of care given to patients in the future.