In a study of 635 patients with multiple sclerosis, cognitive impairment was the strongest predictor of unemployment.
AMSTERDAM—Among patients with multiple sclerosis (MS), cognitive impairment may double the risk of unemployment, according to study results presented by Mark Gudesblatt, MD, Director of the Comprehensive MS Care Center at South Shore Neurologic Associates and Chief of Neurology at Brookhaven Memorial Hospital Medical Center in New York. Dr. Gudesblatt spoke at the 5th Joint Triennial Congress of the European Committee for Treatment and Research in Multiple Sclerosis/Americas Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS/ACTRIMS).
“Cognitive domain functions in all patients with MS were largely reduced, but unemployed patients showed a greater reduction of all cognitive domains relative to the employed patients,” he said. “Cognitive status predicted the likelihood of unemployment more strongly than did Expanded Disability Status Scale (EDSS) scores or disease duration.”
Examining the Associations
Previous research has indicated that patients with MS have high rates of unemployment—and that these may be correlated with cognitive factors, according to Dr. Gudesblatt. “Cognition in patients with MS may be impaired, but the nature, degree, and onset of impairment can be quite difficult to determine clinically,” he added. He noted that clinicians do not routinely assess cognitive function in this population and that the EDSS—which is largely insensitive to cognition—is the routine standard of MS care in trials.
Dr. Gudesblatt and colleagues examined the relationships between cognition, employment, EDSS status, and disease duration in MS. The researchers performed a cross-sectional, retrospective analysis of 635 patients with the disease at a single site in the United States. They categorized patients as employed or unemployed based on self-reports, excluding patients who were students or retired. Patients were assigned to one of four categories based on EDSS scores, and their disease durations were categorized as short (less than five years), medium (between five and 10 years), or long (greater than 10 years).
A validated, computerized battery was used to assess patients’ cognitive function. Their performance in seven cognitive domains—memory, executive function, visual-spatial processing, verbal function, attention, information processing, and motor skills—was assessed through “index” scores adjusted for age and education. The average of all seven scores was considered to be their Global Cognitive Score.
Importance of Assessing Cognition
The patients had a mean age of 45.9 and a mean education level of 14.5 years. Seventy-seven percent were female, and 50% were unemployed. Sixty-eight percent of patients had EDSS scores of 0 to 2.5, 12% had scores of 3 to 4.5, 13% had scores of 5 to 6.5, and 8% had scores of 7 or higher. Thirty-one percent had short disease durations, 35% had medium disease durations, and 34% had long disease durations.
The patients’ risk of unemployment was increased 2.09-fold by cognitive impairment, 1.53-fold by longer disease duration, and 1.46-fold by higher EDSS score. Gender was not significantly associated with unemployment.
Although there were associations between unemployed status and impairment in each of the seven cognitive domains, those associations were strongest in the cognitive domains most affected in MS—executive function, attention, motor skills, and information processing. About 20% of employed patients and 40% of unemployed patients had three or more cognitive domains greater than one standard deviation below average.
These findings highlight the importance of cognitive testing in patients with MS, said Dr. Gudesblatt. “Objective, examiner-independent, multidomain assessment of cognitive function may be an important, useful adjunct to EDSS, neurologic examination, and neuroimaging in routine MS care—and, perhaps, in clinical trials,” he said. “Much like MRI analysis, cognition should be routinely and objectively evaluated in all patients with MS and not left to a vague clinical impression.”
—Jack Baney