Symptom overlap in anxiety and multiple sclerosis

Background: The validity of self-rated anxiety inventories in people with multiple sclerosis (pwMS) is unclear. However, the appropriateness of self-reported depression scales has been widely examined. Given somatic symptom overlap between depression and MS, research emphasises caution when using such scales. Objective: This study evaluates symptom overlap between anxiety and MS in a group of 33 individuals with MS, using the Beck Anxiety Inventory (BAI). Methods: Participants underwent a neurological examination and completed the BAI. Results: A novel procedure using hierarchical cluster analysis revealed three distinct symptom clusters. Cluster one ('wobbliness' and 'unsteady') grouped separately from all other BAI items. These symptoms are well-recognised MS-related symptoms and we question whether their endorsement in pwMS can be considered to reflect anxiety. A modified 19-item BAI (mBAI) was created which excludes cluster one items. This removal reduced the number of MS participants considered 'anxious' by 21.21% (low threshold) and altered the level of anxiety severity for a further 27.27%. Conclusion: Based on these data, it is suggested that, as with depression measures, researchers and clinicians should exercise caution when using brief screening measures for anxiety in pwMS.