Clinical challenges: Managing cognitive dysfunction in multiple sclerosis

Cognitive impairment affects an estimate 40-65% of all people living with multiple sclerosis (MS), and there are often deleterious effects on a person’s ability to earn a living, to treat their disease and to perform the usual activities of daily living.

“MS has been shown to affect information processing speed, visuospatial learning, working memory and verbal fluency, even in the early stages of the disease”, Kathy Zackowski, PhD, OTR, Senior Director of patient management, care and rehabilitation research for the National MS Society, said MedPage today. “The presence and extent of cognitive dysfunction in people with MS varies depending on several factors, including disease progression, disease duration, age and disability.”

Cognitive impairment affects about a third of patients with clinically isolated syndrome, about half of patients with relapsing-remitting MS (RRMS), and 80-90% of those with progressive MS, said John DeLuca, PhD, senior vice president of research and training at the Kessler Foundation in East Hanover, New Jersey, dedicated to helping people with disabilities regain their functions and achieve maximum independence

Most recent from the National MS Society (2018) guidelines recommend early baseline cognitive screening for adult and pediatric patients at least once a year, using the same instrument each year, or more frequently if necessary, Zackowski noted:, is sensitive to changes in mental status during clinical relapses, while other clinical tests such as the Expanded Disability Status Scale may show no change. “

However, “most MS clinics in the United States do not provide any objective assessment of cognitive impairment, which is crucial in relation to self-assessment,” she explained.

Regarding patients who may be most at risk, DeLuca said that “the evidence of cognitive impairment early in the disease is a huge predictor of cognitive decline down the road, as is the presence of loss of volume of gray matter. In patients newly diagnosed or with early-onset MS, these should be your benchmarks for more closely monitoring their cognitive progress. “

Sarah Morrow, MD, director of the London MS Clinic at the University of Western Ontario, agreed that early identification of cognitive symptoms is important: be careful, “she said. MedPage today. “We ask about changes in their cognitive health and MS with each visit.”

“In our clinic, our pilot study of a self-administered computer rehabilitation program, Cogmed working memory trainingsuggested that it improved attention / working memory and had the potential to improve mood in people with MS, ”Morrow said.

Another pilot study randomly assigned 61 people with MS to mindfulness meditation training, computerized adaptive cognitive training (ACT), or a control group on a waiting list. The researchers reported that not only did mindfulness significantly improve processing speed regardless of baseline cognitive state, compared to ACT and control groups, the team was able to extrapolate based on the early data to suggest that l Mindfulness training can also help MS patients regulate negative emotions. .

The guidelines advise annual screening for depression, and Morrow noted that it can be difficult to separate cognitive symptoms from mood symptoms, especially depression and anxiety. Mood symptoms, which can cause people with MS to experience subjective feelings of cognitive impairment, have also been correlated with poor performance on cognitive tests, she added: “What is not clear, that’s if it’s a cause-and-effect relationship. “

DeLuca explained that depression could have a dampening or demotivating side effect on cognition – possibly due to a structural problem in the brain that can also affect cognition, “he said.

Treatment approaches

There is not yet a “gold standard” treatment for cognitive impairment in MS, as there is limited evidence that disease-modifying therapies are effective in treating cognitive dysfunction, noted DeLuca and colleagues. authors in a recent review. On the other hand, a large body of data indicates that cognitive rehabilitation as an inexpensive, low-risk, and effective treatment approach.

Unfortunately, however, cognitive rehabilitation for people with MS is not funded in the United States or Canada, making these programs inaccessible to patients without private insurance, Morrow noted. “We recommend that people with MS continue to perform cognitively stimulating tasks, such as reading, puzzles, playing cards, etc. “

“There is a lot of evidence that cognitive reserve protects against cognitive decline in people with MS,” she continued. “We also recommend exercise. There is weak evidence that exercise helps cognition in people with MS, but it is certainly beneficial for many other aspects of health as well.”

DeLuca noted that impaired processing speed is the most common cognitive impairment in people with MS and has been the target of a growing number of interventional studies.

In the review, he and his coauthors described small studies of several promising home computerized cognitive rehabilitation programs. For example, BrainHQ significantly improved composite cognition scores compared to placebo, and was associated with “impressive” patient compliance in all studies.

Besides, COGNI-TRACK, which provides personalized working memory exercises, has been associated in a small randomized clinical trial with post-treatment improvement in learning and memory, verbal fluency, attention, concentration and processing speed – with the improved processing speed maintained 6 months later, the team noted.

The authors of a search update on the Can do MS website, Abbey J. Hughes, PhD, of Johns Hopkins Medicine in Baltimore, and Pamela H. Miller, MA, CCC-SLP, speech-language pathologist in Denver and consultant for Can Do MS programs, praised the effectiveness of the (recently filed ) Kessler Foundation-Modified history memory technique.

The 10-session memory rehabilitation program combines visualization training and “context training” to improve verbal learning and memory, and according to a review has been shown to be effective in three separate studies, including one brain imaging study which showed increased activity in regions of the brain involved in learning and memory, noted Hughes and Miller.

They added that MS studies also suggest “significant promise” for Attention processing training to improve attention, and RehaCom to improve general cognitive abilities.

“The challenge of cognitive rehabilitation may be finding the right specialist to refer patients to, that is, with experience in MS as well as cognitive rehabilitation,” DeLuca said. “It doesn’t mean we’re out of the woods, it means we need to put in more effort. Data supports cognitive rehabilitation. It’s time to give our dementia MS patients the right treatment. ‘they deserve.”


“The best way to make exercise effective is to make it into a prescribed treatment, and we’re a long way from that because we don’t know the best exercise or the best duration,” DeLuca noted. “The evidence has been mixed, in large part due to methodologically weak studies.”

Zackowski said that while more studies are needed, there is nonetheless “growing evidence that physical exercise, including aerobic training, resistance training and balance training. , can be used to positively manage cognitive disorders associated with MS “.

Some data shows more cognitive benefits with aerobic exercise than with strength training activities, DeLuca noted. “The work we’ve done on the exercise suggests that it must be difficult, and if that challenge is a bit more aerobic, that’s a good thing. And just like harder cognitive exercises have a greater effect, physical effort is [similarly] important.”

In a 2020 study, High-intensity interval training has shown potentially greater effects on fitness and cognition – especially verbal memory – compared to moderate continuous exercise, DeLuca noted. A post-hoc analysis of the results showed significantly greater effects on verbal learning in participants with MS who had impaired cognition compared to intact cognition.

Research into the use of drugs for cognitive problems in people with MS is ongoing, but the data to date is mixed, he said. “It may take 2 years to show an effect and it is small, but drugs could be considered for a patient with cognitive problems at the onset of the disease.”

Given the complexity of being human, there is no better approach, DeLuca said. “Ultimately, there will be three approaches to managing cognitive impairment: medication, exercise, and some elements of cognitive rehabilitation.”

Last updated on November 01, 2021

  • Kate Kneisel is a freelance medical journalist based in Belleville, Ontario.


DeLuca, Morrow and Zackowski did not report any conflicts of interest.

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