People with multiple sclerosis are more likely to have OCD than others. Research says this may be linked with inflammation and stress levels.

Multiple sclerosis (MS) is a serious medical condition that affects the brain and nerves. It can have both physical and mental effects.

Mental health challenges can arise from the stress and uncertainty of living with MS. Certain mental health issues may be due to MS-related nerve damage, which can affect how you feel and react.

Some researchers believe MS can lead to OCD by affecting certain brain areas involved in behavior. We look at what the science says.

Research says that OCD occurs more often than expected in people with MS. For example, a small 2021 study found that over 30% of people with MS also had OCD.

This is higher than usual, given that MS only affects 0.03% of people, and OCD affects 2% of the population (although rates are rising for both conditions).

And, a small 2012 study reported that 16.1% of people with MS also had OCD. The researchers also found that OCD was linked with higher levels of disability, how long the person had MS, and the involvement of sensory and motor nerves.

Some researchers believe that similar biological and mental processes could drive both OCD and MS:

  • Inflammation. High levels of inflammation in the brain is a key feature of both conditions. This inflammation can damage neurons and sensitive areas of the brain that affect behavior.
  • Stress. OCD and MS flares often occur during times of stress. Previous life trauma may contribute to these stress levels.
  • Autoimmune factors. MS is an autoimmune disease, where the body mistakenly attacks its own cells. A 2022 study has suggested that autoimmune factors may contribute to OCD.

Symptoms

Multiple sclerosis (MS) is a serious medical condition that affects the brain and nervous system. The immune system attacks the nerves, damaging the protective layer of myelin that surrounds them. This disrupts nerve signals between the brain and body.

The physical and mental symptoms can include:

  • numbness
  • tingling
  • pain
  • mood changes
  • fatigue
  • memory problems
  • vision problems

Obsessive-compulsive disorder (OCD) is a mental health condition where you experience intrusive, unwanted thoughts (obsessions) and a drive to perform certain routines repeatedly (compulsions) to deal with these thoughts. These symptoms cause much distress and interfere with your daily activities.

Experts aren’t exactly sure what causes OCD, but according to the National Institute of Mental Health, some of the main factors may include genetics, brain structure, and stressful life events.

Since OCD is more common in people with MS, is it possible that MS can cause OCD? No research has directly shown that MS can cause OCD, but some evidence exists in mice.

A 2018 study found that mice with autoimmune encephalitis (AE), a disease similar to MS, groomed themselves much more frequently than mice without AE.

To see if AE was causing this behavior, the researchers removed a type of immune cell called TH17 cells from the mice. These cells are present in the blood and brain of people with MS and could play a key role in the disease process. When the researchers removed the cells, the excess grooming stopped.

Taking it a step further, the researchers then transplanted the TH17 cells from the mice with AE into mice without AE. These mice went on to develop the same obsessive behavior.

While this suggests that factors involved in MS could potentially cause symptoms of OCD, it’s not possible to say if this is the case for humans. The researchers used a mouse model and although AE is similar to MS, it isn’t the same disease, so these results may not apply to MS in humans.

The severity of OCD symptoms tends to fluctuate over time. Flare-ups tend to happen during times of anxiety or stress, and people may rely on compulsions to help them cope with the stress. Stress can also lead to MS flare-ups.

Many stressful events can activate OCD symptoms, including:

  • moving house
  • changing jobs
  • relationship difficulties
  • physical illness
  • death of a loved one
  • bullying

MS is associated with various mental health challenges along with its physical effects. OCD is more common in people with MS. This may be because of shared factors like inflammation and life stress.

It’s too early to say whether MS can cause OCD. A mouse study suggests that immune cells linked with MS may contribute to OCD-like behaviors, but more research is needed to see if this is the case in humans. Such research may provide valuable insight into improving treatment for both conditions.