[Neuropsychological evaluation and psychopathology of multiple sclerosis]

Cognitive and psychiatric disorders have long been described in MS. However, these symptoms were only well evaluated starting about fifteen years ago. More recently, there has been renewed interest in cognitive and psychiatric assessment in MS, especially due to the emergence of new therapies for the disease. Psychiatric symptoms mainly include depression and anxiety. Depression is generally moderate, but there is a risk of suicide that is clearly higher than in the general population. Depression is not correlated with the duration of symptoms, type of disease or level of disability. Mild elation and pathological laughing and crying can be associated and are more frequent in case of severe disease. Bipolar affective disorders and alexithymia are more rare. The question of premorbid personality has been questioned for depression but not confirmed. It has been suspected for bipolar affective disorders. Cognitive disorders are observed in 40 to 65% of the cases at any period of the disease. They mainly include an impairment of working and long-term memory, executive functions and attention whereas global intellectual efficiency is impaired later. While cognitive disorders can be observed early in the course of the disease, there is no correlation with the level of disability or duration of the disease. Progressive MS and especially secondary progressive then primary progressive forms are more subject to cognitive deficits than relapsing remitting MS. For a similar cognitive impairment, progression could be a negative factor for the disease course. Cognitive and psychiatric assessment of patients can be discussed on the basis of why, how and when. Psychiatric assessment is not particularly difficult when there are psychiatric complaints, but cognitive assessment should be explained to the patients and justified when there is no complaint. However, detection of cognitive deficits would lead to better patient management. Psychiatric assessment will mainly use controlled or open interviews and assessment scales to evaluate the level of depression and/or anxiety. For cognitive assessment, short-term batteries focusing on the main dysfunctions are recommended. Psychometric evaluation should not be performed during a period of relapse, hospitalization or immediately after starting drug therapy for depression or anxiety. The cognitive evaluation should be explained to the patient and should include a parallel assessment by a psychologist well trained in MS. The evaluations will be adapted to the situation and the goals. Early interviews evaluate the psychopathological profile that can then be reevaluated during each consultation. Cognitive assessment is mainly proposed in case of interferon therapy, spontaneous complaints of the patient or abnormal difficulties in daily life or occupational activities. In all cases, patient management requires a multidisciplinary approach.