Therapeutic Adherence of Multiple Sclerosis Patients

Multiple sclerosis is a chronic and progressive disease that affects young adults (between 20 and 40 years old), impacting significantly the patients quality of life. The adherence to therapy affects the long-term functional clinical course (lower risk of relapses, reduction in disability progression and quality of life). The non-adherence rate to therapy in multiple sclerosis is estimated at 40%. The main identified causes of non-adherence are: forgetting to take treatment and adverse effects of drugs. Sociocognitive models as the Theory of Planned Behaviour (TPB) have been developed to help to understand and predict health-related behaviours. This model postulates that the intention to adopt a behaviour is one of the major determinants in the context of health. This intention comes from three independent elements : * Personal positive or negative attitudes towards the behaviour, * Social expectations or entourage perception (subjective norms), * Difficulty in accomplishing this behaviour (perceived control) Multiple sclerosis adherence to therapy studies have mainly focused on somatic variables (physical disability, illness duration, type of treatment) and some clinical variables (cognitive impairment, fatigue, depression). The few studies that have examined the multiple sclerosis therapeutic adherence determinants have mainly taken a one-dimensional perspective, such as perceived control. In the FELSA-SEP study, the role of sociocognitive factors (norms and beliefs, perceived threat to disease and health behaviours) and interpersonal factors (social support, patient-doctor relationship) will be explored.