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Fatal Familial Insomnia

What is fatal familial insomnia (FFI)?

Fatal familial insomnia (FFI) is a neurogenerative disease that belongs to a group called prion diseases, which are caused by infectious proteins. FFI mostly affects the thalamus, the part of the brain that controls the sleep-wake cycle. It is also called the relay center of the brain because it helps different parts of the brain communicate. Its characteristic symptom is insomnia that gets progressively worse and leads to significant mental and physical deterioration. Symptoms usually first occur during the middle of life, typically between age 32 and 62. Because it is so rare, the exact prevalence of this disorder is unknown.

What are the symptoms of FFI?

  • Sudden insomnia that gets worse over time
  • Rapidly worsening dementia
  • Vivid dreaming
  • Lack of appetite
  • Weight loss
  • Too high or low body temperature
  • Anxiety
  • Depression
  • Panic attacks
  • Phobia
  • High blood pressure
  • Uncoordinated movement
  • Erectile dysfunction
  • Vision problems
  • Intense confusion
  • Hallucinations
Near the end of the course of the disease, the dementia may progress to the point that the person may not be able to walk or talk. The insomnia can reach a point where the patient is completely unable to sleep.

What causes FFI?

FFI is a neurogenerative disease, a disease that over time leads to fewer neurons, or nerve cells. The reduction of nerve cells in the thalamus causes FFI’s symptoms. FFI is inherited as an autosomal dominant trait. Human traits are inherited from one’s father and mother. They each contribute a gene, which interacts with the other. In dominant disorders, only a single copy of the mutated gene is needed for the disease to appear. FFI occurs because of a mutation in the PRNP gene. In rare cases, FFI can occur in people who have no family history of it, meaning the mutation happens spontaneously.

How is FFI diagnosed?

FFI can be diagnosed with:
  • Recording characteristic symptoms
  • Detailed recording of patient history
  • Clinical evaluation
  • Specialized testing
  • Molecular genetic testing
  • Sleep study
  • PET scan

What are the treatments for FFI?

Currently, there are no effective treatments for FFI, but researchers are searching for treatment and a cure. Symptomatic treatment that can help includes:
  • Anti-seizure medications
  • Psychosocial support
  • Genetic counseling

Where can I find out more about FFI?

Fatal Familial Insomnia Articles