Editing Fatal insomnia (section)

==Signs and symptoms==
The disease has four stages:<ref>{{cite web|url=http://www.world-of-lucid-dreaming.com/fatal-familial-insomnia.html|title=Dying To Sleep: Fatal Familial Insomnia (FFI) | vauthors = Turner R |website=www.world-of-lucid-dreaming.com |access-date=22 March 2018}}</ref>

# Characterized by worsening [[insomnia]], resulting in [[panic attack]]s, [[paranoia]], and [[phobia]]s. This stage lasts for about four months.
# [[Hallucination]]s and panic attacks become noticeable, continuing for about five months.
# Complete inability to [[sleep]] is followed by rapid loss of [[weight]]. This lasts for about three months.
# [[Dementia]], during which the person becomes unresponsive or mute over the course of six months, is the final stage of the disease, after which death follows.
Clinically, FFI manifests with a disordered sleep-wake cycle, [[dysautonomia]], motor disturbances, and neuropsychiatric disorders.

Other symptoms include profuse sweating, [[miosis]] (pinpoint pupils), sudden entrance into [[menopause]] or [[impotence]], neck stiffness, and [[high blood pressure|elevation of blood pressure]] and heart rate. The sporadic form of the disease often presents with [[Diplopia|double vision]]. Prolonged constipation is common as well. As the disease progresses, the person becomes stuck in a state of pre-sleep limbo, or [[hypnagogia]], which is the state just before sleep in healthy individuals. During these stages, people commonly and repeatedly move their limbs as if they were  dreaming.<ref name="Cortelli et al.">{{cite journal | vauthors = Cortelli P, Gambetti P, Montagna P, Lugaresi E | title = Fatal familial insomnia: clinical features and molecular genetics | journal = Journal of Sleep Research | volume = 8 | issue = Suppl 1 | pages = 23–29 | date = June 1999 | pmid = 10389103 | doi = 10.1046/j.1365-2869.1999.00005.x | s2cid = 24399165 }}</ref>

The age of onset is variable, ranging from 13 to 60 years, with an average of 50.<ref>{{cite web |title=Episode 25: Fatal Insomnia |url=https://www.obscuracrimepodcast.com/podcast/2018/10/10/episode-25-fatal-insomnia |website=Obscura: A True Crime Podcast}}</ref> The disease can be detected prior to onset by genetic testing.<ref>{{cite magazine | vauthors = Max DT |title=The Secrets of Sleep |url=https://www.nationalgeographic.com/magazine/article/sleep |magazine=National Geographic |volume=217 |issue=5 |date=May 2010 |page=74 }}</ref> Death usually occurs between 6–36 months from onset. The presentation of the disease varies considerably from person to person, even among people within the same family; in the sporadic form, for example, sleep problems are not commonly reported and early symptoms are [[ataxia]], cognitive impairment, and double vision.<ref>{{Cite web|url=https://www.merckmanuals.com/en-ca/professional/neurologic-disorders/prion-diseases/fatal-insomnia|title = Fatal Insomnia - Neurologic Disorders}}</ref>