Do you ever walk into a room and forget why you went in there? Struggle to find the right words in a conversation? Or have trouble remembering something you just learned?

More than half of people living with multiple sclerosis (MS) experience cognitive changes that can affect memory, attention, and thinking. These changes may make you wonder whether MS is connected to dementia.

Some research suggests people with MS may have a higher risk of developing dementia, although results vary across studies. Symptoms of dementia can overlap with some cognitive problems linked to MS, which can make the two hard to tell apart.

That said, memory loss and other cognitive changes don’t always mean dementia. In this article, we’ll look at possible connections between multiple sclerosis and dementia, including Alzheimer’s disease, and ways to help support brain health.

Does MS Cause Dementia or Alzheimer’s?

MS can cause cognitive changes, but that doesn’t mean a person has Alzheimer’s. MS and Alzheimer’s are different diseases, although it’s possible to have both. Research on the connection between MS and dementia has had mixed results.

A large 2022 study found that adults with MS had a higher incidence of Alzheimer’s disease and related dementia than adults without MS, especially at ages 45 to 64. A 2025 review of 10 studies also found that people with MS had a higher risk of dementia than people without MS.

However, a 2024 study reported less Alzheimer’s-related amyloid buildup in people with MS. The findings suggest that people with MS may have a lower risk of Alzheimer’s disease, although more research is needed.

Overall, the evidence is still mixed. People with MS may have a higher risk of dementia overall, but the connection between MS and Alzheimer’s disease is less clear.

Cognitive Symptoms in MS

Cognitive symptoms affect skills such as learning, memory, attention, and reasoning. Some people may notice cognitive changes as an early symptom of MS.

These problems often involve memory issues, slowed information processing, difficulty with attention, and challenges with visual and spatial awareness (how a person perceives space and distance).

In MS, the severity of cognitive problems doesn’t always match the severity of a person’s physical symptoms or disability. Cognitive changes in MS may be linked to lesions in the brain or brain atrophy (shrinkage).

Cognitive problems are generally more common and more severe in progressive forms of MS. This includes both secondary progressive MS and primary progressive MS.

Some people living with MS describe cognitive symptoms as brain fog. Brain fog is an informal way to describe trouble with thinking, focus, memory, or processing information.

“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.”

Cognitive Symptoms of MS vs. Dementia

Cognitive problems in MS are often mild, while dementia symptoms typically get worse over time and interfere with daily life.

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

• Communication or finding the right words
• Visual-spatial tasks, such as getting lost in a familiar place
• Problem-solving
• Planning and organizing
• Orientation, such as being confused about the time, day, or place
• Decision-making
• Understanding complicated tasks

Behavioral and psychological symptoms may also be part of dementia. These can include:

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

Some of these symptoms can overlap with cognitive changes caused by MS. However, dementia is more likely to worsen over time and affect a person’s ability to function independently.

Symptoms in both conditions can have a major effect on everyday life. They can affect work, relationships, and daily routines.

A 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.”

Treatment for MS Cognitive Symptoms

Disease-modifying drugs can help reduce MS disease activity and slow disease progression. Some research suggests they may also help preserve cognitive function, but their effects on cognition are still being studied. Medications haven’t been shown to consistently improve MS-related cognitive symptoms.

Research suggests cognitive rehabilitation may help improve thinking and memory skills in people with MS.

There are several medications available to treat symptoms of dementia, but no treatment can fully stop the condition from getting worse.

When To Talk to Your Doctor

If you or a loved one has new memory problems or other dementia symptoms, talk with your primary care doctor or neurologist. It can feel embarrassing to bring up changes in your memory, but being honest helps your care team look for possible causes.

Symptoms that look like dementia may sometimes improve if another treatable issue is causing them. For example, some medicines, vitamin deficiencies, thyroid problems, infections, or other health conditions can cause symptoms that look like dementia. This is one reason it’s important to talk with a doctor about new or worsening symptoms.

If your doctor is concerned about dementia or another condition, they may order blood tests, brain imaging, cognitive testing, or neuropsychological testing.