Anti-cholinergic medications for bladder dysfunction worsen cognition in persons with multiple sclerosis

Bladder dysfunction is common in persons with MS (PwMS), often due to detrusor muscle overactivity. Anticholinergic medications are considered the first line treatment for bladder dysfunction and are known to worsen cognition in healthy older adults and in persons with dementia. Yet, it is not known if these medications have the same effect on PwMS. Thus, the Objective of this prospective matched-cohort study was to determine if anticholinergic medications affect objective measures of cognition in PwMS. We recruited PwMS starting either oxybutynin or tolterodine (cases). Cases and controls were tested with the Brief International Cognitive Assessment for MS (BiCAMS) battery prior to starting anticholinergic medications and 12 weeks later. The primary outcome was change on the Symbol Digit Modalities Test (SDMT) between groups; secondary outcomes were changes on the other BiCAMS measures. Analysis of Covariance with baseline measures as covariates to assess the significance of between group differences was performed at 12 weeks. Forty eight PwMS starting anticholinergic medications and 21 matched PwMS controls were recruited. There was a significant difference (p < 0.001) in the change on the cognitive measures over 12 weeks between groups. The controls demonstrated improvement, consistent with practice effect, while the cases remained unchanged. This study demonstrates that anticholinergic medications may have a negative effect on cognition in PwMS; further confirmatory studies are needed.