Kendall Jenner has shared details of a mysterious health issue.

Model and reality television alumni, Kendall Jenner, has admitted to suffering a mysterious health issue in a preview for the latest episode of Keeping Up With The Kardashians. 

The 20 year old shared that she’s been having unusual sleep struggles for some time.

“I wake up in the middle of the night and I can’t move,” she explained.

In the episode teaser, Kendall makes a phone call to mother and manager Kris Jenner in search of answers.

“I think you’ve just got anxiety,” Kris says.

“Everyone says I’m fine, but I don’t feel fine,” Kendall replies.

Current statistics suggest around 14 per cent of all adult Australians are affected by an anxiety disorder, according to Sane Australia.

American resources such as the National Institute of Mental Health estimate anxiety disorders affect around 18 per cent of the American population.

Sadly, women are more likely to be afflicted than men.

Kris's guess about Kendall's mystery illness may sound a little flippant, but anxiety disorders can cause serious issues if symptoms are left untreated.

@esteelauder #KJ4EL #EsteeModel

A photo posted by Kendall (@kendalljenner) on May 5, 2016 at 3:42pm PDT

The Daily Mail reported the above outtake was filmed in the lead up to the European Fashion Weeks. Kendall was noticeably missing from the Paris, London and Milan catwalks.

Vogue explained her absences at the time with the presumption the model was purposely missing shows in an attempt to raise her demand.

"Don’t be surprised if Jenner appears at only one or two more shows this season. In keeping herself scarce, she’s doing the smartest thing a model can do: creating a demand for her services," they wrote.

People reported Kendall has previously admitted to suffering from the rare condition of trypophobia.

“Anyone who knows me knows that I have really bad trypophobia,” she wrote on her website and app. (Post continues after gallery.)

“Trypophobics are afraid of tiny little holes that are in weird patterns. Things that could set me off are pancakes, honeycomb or lotus heads (the worst). It sounds ridiculous but so many people actually have it!” she said.

“I can’t even look at little holes – it gives me the worst anxiety. Who knows what’s in there?"

The full story behind what's affecting Kendall will hopefully be explained on the next episode of KUWTK airing this Sunday at 9pm, US time.