Cognition, Fatigue, and Health-related Quality of Life in Multiple Sclerosis: Exploring the Role of Polypharmacy and Anticholinergic Medication Burden

Abstract

OBJECTIVE: Recent evidence suggests that polypharmacy, or the daily use of multiple medications, is common among individuals with multiple sclerosis (MS). Some medications have anticholinergic properties that increase risk of adverse effects such as sedation and impaired cognition. No study has examined the use of anticholinergic rating scales in MS. We explored the relationships between polypharmacy, anticholinergic burden, fatigue, cognition, and health-related quality of life in a group of individuals with MS. METHODS: The sample included 90 patients with MS. Participants completed objective cognitive evaluation as well as measures of self-reported cognition, fatigue, health-related quality of life. Participants also provided information about comorbidities and use of lifestyle-related substances. A list of participants’ medications was obtained at the time of testing, from which we determined polypharmacy status and anticholinergic burden. RESULTS: Approximately 44% of the MS sample had polypharmacy. The number of daily medications was negatively correlated with cognitive performance, rs = -0.45, p < .001. Additionally, the Drug Burden Index (DBI) accounted for additional variance in cognitive performance beyond that explained by age, education, MS disease duration, and comorbidities, ΔR2 = .12, F(5, 84) = 7.84, p < .001. Polypharmacy and anticholinergic burden indices did not predict fatigue or HRQoL when accounting for relevant covariates such as disability and mood symptoms. The Anticholinergic Cognitive Burden (ACB) scale explained roughly 5% of variance in perceived cognition above and beyond disease characteristics and mood symptoms. CONCLUSIONS: Tools like the DBI and ACB may assist in prediction of objective and perceived difficulties with cognition in adults with MS. Results suggest that researchers should account for polypharmacy and anticholinergic medication effects when evaluating fatigue and cognition in MS. Similarly, clinicians and patients should carefully weigh the costs and benefits of prescribing multiple medications, as these may contribute to iatrogenic problems with cognition, fatigue, and HRQoL.