Association of patient-reported cognitive impairment with quality of life and employment in multiple sclerosis

Background:Cognition is frequently affected in persons with multiple sclerosis (MS). Cognitive impairment (CI) is associated with decreased quality of life (QOL) and employment status. Yet, CI assessed using patient-reported outcome measures is not as well studied and is thought to be influenced by other symptoms. Health Utilities Index 3 (HUI3) is a multi-attribute health-status classification system that assesses 8 different single attributes, including cognition. Methods:The North American Consortium of Multiple Sclerosis (NARCOMS) Registry, a voluntary, self-report registry for persons with MS, Spring 2019 survey collected the HUI3 and self-reported assessment of health-related QOL (RAND-12), cognitive status, depression, fatigue, disability, employment, disease-modifying therapy use, and sociodemographic data. We assessed the relationship between patient-reported cognitive CI from the HUI3 (HUI-C), QOL, and employment while adjusting for factors previously associated with the outcomes. For employment outcomes, the cohort was limited to participants 65 years of age or younger. Results: Of the 6,227 respondents, 56.4 % reported cognitive difficulty with the HUI-C. After adjusting for multiple covariates, cognitive difficulty was associated with 1.2 point lower physical QOL for each 0.1 decrease in HUI-C (p < 0.0001). Mental QOL decreased by 2 points for each 0.1 decrease in HUI-C (p < 0.0001). Cognitive difficulty was associated with a 10 % decreased odds of employment in the multivariable model (p < 0.0001). Discussion: Patient-reported CI was associated with lower health-related and vocational outcomes for MS patients, even after accounting for age, income, depression, fatigue, and disability associated with cognition. The HUI-C is a single attribute score derived from the HUI3 that may facilitate the evaluation of CI in MS.