Do you ever walk into a room and forget why you went in there? Or struggle to find the right words in a conversation? More than half of people living with multiple sclerosis (MS) experience cognitive problems, and some may wonder whether MS can lead to dementia. In fact, there is some evidence that people with MS may have a higher risk for developing dementia.

Symptoms of dementia can overlap with some of the cognitive problems associated with MS, and it may be difficult to tell the two apart. That said, memory loss and other forms of cognitive impairment (reduced ability to think clearly) don’t necessarily mean you have dementia. In this article, we’ll look at what studies revealed about the potential connections between MS and dementia, and we’ll discuss ways to help keep your brain as healthy as possible as you age.

What Is Dementia?

Dementia refers to a broad category of symptoms that affect thinking, memory, and social interactions and that are severe enough to affect your daily life. It’s important to know that dementia itself does not refer to a specific disease. Many conditions can cause dementia, including Alzheimer’s disease and Parkinson’s disease. Other types of dementia include Lewy body, frontotemporal, and vascular dementia.

Typical symptoms of dementia include memory loss or difficulty with one or more of the following:

• Communication or the ability to find the right words
• Visual-spatial tasks, such as getting lost in your own neighborhood
• Problem solving
• Planning and organizing
• Coordination and motor function
• Orientation, such as being confused about what time or day it is, or where you are
• Decision-making
• Understanding complicated tasks

Sometimes, behavioral and psychological symptoms are a part of dementia. These can include:

• Personality changes
• Socially inappropriate behavior
• Agitation
• Depression or anxiety
• Paranoid behavior
• Hallucinations

It is often a family member or caregiver who first notices these symptoms, along with memory problems.

Symptoms of memory loss may be reversible, depending on their cause. In many situations, based on the main symptoms and the area that is affected, your doctor can figure out what is causing dementia.

Dementia vs. Alzheimer’s Disease

In older adults, dementia is most commonly a result of Alzheimer’s disease. In this condition, proteins called beta-amyloid and tau build up in the brain. This causes abnormalities that get worse over time. Eventually, the brain shrinks and brain cells die. This process is known as brain atrophy. Alzheimer’s disease causes the progressive symptoms of dementia, and this results in a slow and steady decrease in thinking skills, memory, and social abilities. Additionally, Alzheimer’s typically affects older adults: Over 70 percent of people with Alzheimer’s are 75 or older, according to Mayo Clinic.

Memory loss is the hallmark of Alzheimer’s disease. Over time, this defining symptom worsens, and loved ones will typically notice the change. Other symptoms of dementia also may appear.

Does MS Cause Dementia or Alzheimer’s?

MS causes cognitive changes, but it does not cause Alzheimer’s, as these are two different diseases. That said, it is possible for a person to have both. A 2022 study found an increase in Alzheimer’s rates among people with MS at both younger (45 to 64) and older (65 and up) ages. A 2024 study that considered clinical and laboratory characteristics noted that people with MS had a lower risk of Alzheimer’s. Because both diseases can cause issues with cognitive function, it can be difficult for researchers to determine the exact cause and mechanism. More research on the association between MS and Alzheimer’s is needed.

It’s also possible to have both MS and a different disease that causes dementia. One prevalence study found that in one clinic, 22 percent of people with MS qualified as having possible dementia. Their cognitive impairments consisted mostly of memory problems and slowed thinking. When Alzheimer’s disease causes dementia in a person with MS, the impairment usually affects more aspects and is usually severe.

Another neuroscience study found that people with MS had a 50 percent higher risk of dementia compared to those without MS. The study followed a large group of veterans with MS for roughly 10 years, highlighting the importance of early testing for dementia in general.

Cognitive Symptoms in MS

Cognitive symptoms that affect learning, memory, and reasoning are aspects of MS that were first described in the medical community in 1849. Studies have shown that between 50 percent and 66 percent of people with MS experience some form of cognitive impairment. These cognitive impairments often involve memory problems, slowed information processing, difficulty with attention, and challenges with visual and spatial awareness.

Neurology research has shown that the length of time a person has had MS isn’t a reliable indicator of whether they experience cognitive changes. Also, the severity of cognitive deficits doesn’t seem to be related to the severity of physical symptoms or physical disability, and lesions (damaged areas of nerve tissue) aren’t present on MRI scans of white matter (nerve networks) in the brain. Secondary progressive MS, a subtype of MS, seems to be associated more closely with cognitive decline than other types of MS.

Cognitive Symptoms of MS vs. Dementia

Some people living with MS experience mild cognitive impairment, also known as brain fog, and others may meet the criteria to be diagnosed with dementia. But the main difference between the cognitive symptoms of MS and apparent dementia is how severe the symptoms are. Even though a substantial percentage of people with MS have cognitive impairment, this symptom tends to be on the mild side and involve difficulty remembering information and remaining focused on a task.

That said, the cognitive symptoms of MS have high variability and sometimes they can seriously affect routines and quality of life. It’s important to keep in mind that aging, fatigue, and depression, which are often associated with MS and some medications, can also result in cognitive deficits.

One member of MyMSTeam shared, “I forget words, and I’m hesitant to talk for fear of embarrassing myself. I’m also afraid someone will think I have some form of dementia.”

“I’ve been struggling with brain fog for 11 years,” wrote another member. “MS was suggested but never pursued because the MRI didn't show enough evidence. I am 68 now and fighting dementia-like symptoms. I’ve had multiple disconnected mystery symptoms for all that time. … No one ever connected them before.”

Treatment for MS Cognitive Symptoms

MS treatment is based on the use of disease-modifying drugs that can help reduce disease activity and slow down the disease’s progression. These drugs could also help prevent the development of cognitive changes by keeping disease activity low. However, although there are a number of medications available to treat certain types of dementia, none have been shown to be successful in treating MS-related cognitive symptoms once those symptoms are established. Research on cognitive rehabilitation (an intervention to improve skills like thinking and memory with practice) continues to grow, and it may show promise for individuals with MS. Yoga has been shown to improve MS-related fatigue, which can be a cause of cognitive dysfunction in MS.

When To Talk to Your Doctor

If you or your loved one has new problems with memory impairment or other dementia symptoms, check with your primary care doctor or neurologist as soon as possible. Sometimes it can feel embarrassing to tell your health care team about new difficulties with memory or performing daily activities, but it’s important to be honest about them. Some causes of memory loss are reversible, so it’s important to get a proper diagnosis and treatment quickly.

If your doctor is concerned about cognitive problems that resemble dementia, they may order blood tests, brain imaging, and possibly neuropsychological testing to determine the right diagnosis and treatment plan.

Tips for Keeping Your Brain Healthy

If you are living with MS, keeping your brain healthy is important no matter what your age. There are a number of steps you can take to keep your mind active, reduce certain risk factors, and slow memory loss.You might consider:

• Regularly getting exercise that’s possible for you
• Getting enough sleep
• Following a nutritious, balanced diet such as a Mediterranean-style eating pattern
• Keeping up connections with friends, loved ones, and others
• Giving your brain a workout by reading, doing puzzles, and playing games
• Protecting your brain health with regular blood pressure, blood sugar, and cholesterol checks

Talk With Others Who Understand

MyMSTeam is the social network for people with MS and their loved ones. On MyMSTeam, more than 216,000 members come together to ask questions, give advice, and share their stories with others who understand life with MS.

Are you living with MS and worried about dementia? Do you have any favorite strategies to help keep your brain sharp? Share your experience in the comments below, or start a conversation by posting on your Activities page.