Ashton Kutcher reveals he battled a 'rare form of vasculitis' and is 'lucky to be alive'

Ashton Kutcher says he's "lucky to be alive” after revealing a battle with an autoimmune disorder that impacted his ability to see, hear and walk.

The 44-year-old actor spoke about having vasculitis in an exclusive clip for Access Hollywood from an upcoming episode of National Geographic’s “Running Wild with Bear Grylls: The Challenge.”

“Like two years ago, I had this weird, super rare form of vasculitis, that like knocked out my vision, it knocked out my hearing, it knocked out like all my equilibrium," Kutcher told Bear Grylls.

The "That '70s Show" alum said it took a year for his senses to recover.

“You don’t really appreciate it, until it’s gone,” Kutcher said, “Until you go, ‘I don’t know if I’m ever going to be able to see again, I don’t know if I’m ever going to be able to hear again, I don’t know if I’m ever going to be able to walk again.’”

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Vasculitis refers to inflammation of blood vessels which can cause restricted blood flow, according to the Mayo Clinic. There are many types of vasculitis, and most of them are rare. The condition can be short term or long lasting, the clinic also notes.

Kutcher told Grylls the situation taught him a lesson in perseverance.

“The minute you start seeing your obstacles as things that are made for you, to give you what you need, then life starts to get fun, right? You start surfing on top of your problems instead of living underneath them," Kutcher said.

The actor clarified in a tweet Monday that he's "fully recovered."

"All good. Moving on. See you at the 2022 NY Marathon," he added.

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Kutcher also tries to maintain an optimistic mentality when grappling with worldly events like climate woes and the war in Ukraine. His wife, Mila Kunis, was born in Ukraine.

"It’s just easy to get trapped in the news cycles," Kutcher told USA TODAY in July. "We've got these machines in our pockets that want to send us notifications. ... And they’re going to show you the most aggressive news stories, because that’s what causes you to engage with them."

Kutcher said it's important to remember to put phones away and remember the majority of people don't have extreme views.

"So it’s easy to get pessimistic," Kutcher said. "The majority of people aren’t engaging in extreme behavior. They just want to have good happy lives and take care of their kids. And that is something to be extraordinarily optimistic about."

Kutcher’s episode of “Running Wild with Bear Grylls: The Challenge,” airs Monday night on National Geographic.

Contributing: Marco della Cava

This article originally appeared on USA TODAY: Ashton Kutcher reveals he had vasculitis, rare autoimmune disorder