Ruth Ann Marrie, MD, PhD, a professor in the Department of Internal Medicine, Section of Neurology, and Department of Community Health at the University of Manitoba, and colleagues cited estimates that cognitive impairment occurs in 40% to 70% of persons with MS. While previous studies have suggested that depression influences cognition in MS, they note that findings have been inconsistent, and that there has been little investigation of such effect from anxiety in MS and in other IMID without direct CNS involvement.
"We aimed to examine the association of anxiety and depression on cognitive function in MS, and to determine whether the effects of anxiety and depression on cognition in MS were similar to those observed in inflammatory bowel disease (IBD) and rheumatoid arthritis (RA), and in individuals with anxiety and depressive disorders without an IMID," investigators wrote.
That said, they recognized the challenges of disentangling the role of anxiety symptoms on cognitive function in patients with major depression.
In an accompanying editorial, Anthony Feinstein, MD, PhD, of the Department of Psychiatry at Sunnybrook and Women's College Health Science Centre in Toronto, CA, and colleagues elaborated on the challenges in assessing multiple aspects of mentation, and commended the investigators for "an innovative approach that extends our understanding of the association between cognitive abnormalities and symptoms of depression and anxiety."