Cedars-Sinai hospital's report on the syndrome report that it is extremely rare.
It effect long term DAILY users of marijuana , long term meaning at least twenty years of consistent use.
The syndrome in those who meet this criteria effect only one in three of those asking to be checked for it, more often than not the same symptoms come from reckless overeating after smoking and suffering "the munchies"
Pretty much a scare piece, you're more likely to develop the same symptoms from heavy drinking of alcohol or eating spicy food under the same circumstances.