Functional neurological symptom disorder: What to know

FND, also known as conversion disorder, is a complicated syndrome that causes neurological symptoms without a visible structural abnormality in the nervous system. Although the actual reason is unknown, stress is thought to be a crucial factor.

FND affects 4–12 persons per 100,000, according to the Journal of Psychiatry and Neuroscience.

FND is more common in adolescents and adults than it is in children. People who live in rural areas and military people may be more susceptible to FND than other individuals.

When to consult a physician

If a person has any of the signs and symptoms of FND, they should see a doctor, especially because the symptoms might be confused with those of other medical illnesses. Early intervention may be necessary in these circumstances to resolve the underlying issue.

Untreated FND can lead to more problems or debilitation, thus early management is key.

neurological symptom disorder

Causes

FND’s specific cause is unknown.

According to one idea, FND is caused by an “internal struggle,” and the symptoms are the body’s attempt to deal with the stress.

For example, someone who believes violence is immoral yet feels compelled to react aggressively in the face of a distressing circumstance may have numbness in their arms or legs as a method of repressing the urge to punch or kick.

FND can, however, develop in the absence of stress, depression, or other psychological causes in some people.

Certain research has found that functional connectivity in key regions of the brain, particularly those that govern muscles and senses, has been found to be reduced in patients with FND. This is a sign that the body has lost control of its bodily movements or behaviors.

  • speech problems
  • tremors or spasms
  • vision problems, such as loss of vision or double vision
  • weakness or paralysis in the limbs
  • fainting
  • jerky movements
  • numbness, tingling, or pain, often on one side of the body
  • problems walking, or gait disorder
  • seizures

Duration and intensity of symptoms

Symptoms may appear and disappear, or they may last for a long time. Their severity and placement can differ.

Symptoms may disappear in a short period of time in certain circumstances. However, in some cases, they might last for months or even years, impairing a person’s ability to work and do daily tasks.

The symptoms of FND can be as debilitating as those of multiple sclerosis or Parkinson’s disease, according to FND Hope, a non-profit patient advocacy organization for persons with FND.

Risk factors

The following are some of the factors that may enhance your chances of acquiring FND:

  • distressing life events
  • childhood traumas
  • dissociative disorders
  • personality disorders
  • having a family member with FND

Diagnosis

FND is difficult to diagnose because the symptoms are not caused by an underlying medical condition and might mirror the symptoms of a variety of other illnesses. Doctors should not rule out FND because tests for other diseases have come up negative.

In many circumstances, a diagnosis will entail both a neurologist and a psychiatrist. A neurologist can rule out underlying neurological disorders, while a psychiatrist can rule out alternative psychiatric causes and confirm a FND diagnosis.

Although there is no standard test for FND, the following tests are widely used to diagnose it:

A health evaluation and physical examination

A doctor will take note of any symptoms and inquire about life changes, traumas, and major stressors. They may also ask for a complete medical and family history.

Functional tests may be performed by a doctor to assess a person’s reflexes, balance, and bodily motions.

Imaging tests

X-rays and MRI scans can help determine whether your symptoms are caused by a brain injury or neurological abnormality.

Electroencephalogram scans can discover disorders connected with the brain’s electrical activity, such as epilepsy, by tracking brain waves.

DSM criteria

A psychiatrist will establish a diagnosis based on the diagnostic criteria outlined in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5)

To be diagnosed with FND, people must:

  • have one or more symptoms that interfere with their movement or senses and are not under their control.
  • won’t be able to link their symptoms to drug usage or a physical or neurological condition.
  • find that their symptoms cause substantial distress or issues socializing, at work, or in other areas of their lives, or that their symptoms are severe enough to warrant medical attention.

Common misdiagnoses

Because of the symptoms of FND, it’s possible that doctors will misdiagnose it.

According to a 2005 study, the rate of misdiagnosis for FND has averaged at 4% since 1970. According to another study, 41% of people with uncommon disorders have received an inaccurate diagnosis at least once.

The following are people of common FND misdiagnoses:

  • myasthenia gravis, a muscle weakness disorder
  • neurological disorders affecting the central nervous system, such as epilepsy, multiple sclerosis, polyneuropathy, and Parkinson’s disease
  • a spinal cord injury
  • stroke
  • Guillain-Barré syndrome, a rare autoimmune disorder characterized by muscle weakness and pain
  • HIV or AIDS
  • health anxiety, a psychological condition characterized by excessive thoughts about having an undiagnosed illness
  • lupus, an autoimmune disease with symptoms including fatigue and joint pain

Treatment

Symptoms in some people with FND can go away without medication, especially once they’ve been assured that their symptoms aren’t caused by a more serious condition.

Treatments, on the other hand, may be beneficial for persons suffering from:

  • symptoms that are slow to resolve
  • recurrent symptoms
  • co-occurring psychological conditions
  • severe FND symptoms

Doctors usually advise a mix of treatments. The following therapies are available:

  • Transcranial magnetic stimulation (TMS): Magnetic fields are used to activate specific parts of the brain in this treatment. TMS may be beneficial for people with FND, according to some reports, however there is limited data at this time.
  • Lifestyle changes: Some people with FND may benefit from activities that reduce stress and anxiety, such as yoga, meditation, and progressive muscle relaxation. Stress can be reduced by eating a well-balanced diet, getting adequate sleep, cultivating strong relationships, and keeping a high quality of life.
  • Psychotherapy: Working with a psychotherapist or psychologist can help people with FND caused by a stressful or traumatic experience or an underlying mental health condition. Cognitive behavioral therapy is used by some people with FND.
  • Physical therapy: Physical therapy can help people with FND’s physical symptoms such restricted movement, muscle weakness, and pain.
  • Medication: Antidepressants or antianxiety medications may be used to treat the stress or anxiety that contributed to the development of FND.

Conclusion

Symptoms vary in duration and severity from person to person. The symptoms are usually not life threatening, but complications can be debilitating and lower a person’s quality of life.

Many people with FND recover after they are assured that their symptoms are not caused by a physical condition or acute illness.

Some people, however, may endure continuous symptoms, recurrence symptoms, or the emergence of new symptoms at a later time, especially if they:

  • symptoms are not stress-related
  • symptoms include tremors or seizures
  • there are co-occurring psychological conditions
  • they delay treatment
  • symptoms develop slowly
  • symptoms do not improve quickly

Sources:

  • https://rarediseases.info.nih.gov/diseases/6191/conversion-disorder
  • https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC6306282/
  • https://rarediseases.org/rare-diseases/fnd/
  • https://www.medicalnewstoday.com/articles/318534
  • https://fndhope.org/fnd-guide/symptoms/
  • https://www.ncbi.nlm.nih.gov/pubmed/27385746
  • https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4815435/
  • https://www.ncbi.nlm.nih.gov/pubmed/21795652
  • https://www.bmj.com/content/early/2004/12/31/bmj.38628.466898.55