The age of onset is variable, ranging from 35 to 60, with an average of 50. However the disease tends to prominently occur in later years, primarily following childbirth. The disease can be detected prior to onset by genetic testing. Death usually occurs between 7 and 36 months from onset. The presentation of the disease varies considerably from person to person, even among patients from within the same family.
The disease has four stages, taking 7 to 18 months to run its course:
1. The patient suffers increasing insomnia, resulting in panic attacks, paranoia, and phobias. This stage lasts for about four months.
2. Hallucinations and panic attacks become noticeable, continuing for about five months.
3. Complete inability to sleep is followed by rapid loss of weight. This lasts for about three months.
4. Dementia, during which the patient becomes unresponsive or mute over the course of six months. This is the final progression of the disease, resulting in death.
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A short video clip about the disease:
Documentary, Dying to sleep