Relationship between neuropsychiatric symptoms and cognition in multiple sclerosis: A systematic review

The results of previous research on the relationship between neuropsychiatric symptoms and cognition in multiple sclerosis (MS) have been mixed. The aim of this systematic review was to examine the evidence on the relationship between neuropsychiatric symptoms and different cognitive domains in adult (≥18 years) MS patients. A literature search was conducted in the Ovid Medline, PsycInfo, Scopus, and Web of Science databases. A total of 4,216 nonduplicate records were identified, and after screening, 37 studies met the inclusion criteria and were included in the systematic review. Higher levels of depressive symptoms were related to deficits in processing speed, verbal memory, executive functions, visuospatial functions, and attention in MS patients. Symptoms of anxiety were not consistently related to any of the cognitive functions, but the relationship to deficits in visual memory received a minimal amount of support. Higher levels of apathy were most clearly associated with impairment in executive functions, but the association with deficits in visuospatial functions, visual memory, working memory, and processing speed was also supported. The results indicate that more neuropsychiatric symptoms, especially depressive symptoms and apathy, are associated with cognitive dysfunction in MS patients. These results can be utilized in the clinical examination and treatment planning of MS patients.