190530 Ashton Kutcher
Ashton Kutcher Image Credit: Reuters

For about a year, Ashton Kutcher had difficulty seeing, hearing and walking.

The actor revealed his battle with vasculitis — an autoimmune disease that inflames the blood vessels — in an upcoming episode of National Geographic’s “Running Wild With Bear Grylls: The Challenge.” According to a clip of the episode, Kutcher spoke of his health struggles while hiking through a thick forest with adventurer Bear Grylls, the show’s host.

“You don’t really appreciate it until it’s gone, until you go, ‘I don’t know if I’m ever gonna be able to see again. I don’t know if I’m gonna be able to hear again, I don’t know if I’m going to be able to walk again,’” said Kutcher, who is known for his roles in “That ‘70s Show” and “The Butterfly Effect.”

“I’m lucky to be alive,” he added.

In the preview, Grylls called Kutcher’s experience with vasculitis “a terrifying journey,” but one that made the actor strong and resilient. “What do they say in survival? Storms make you stronger, and I think he is living proof of that,” Grylls added.

It is not clear which type of vasculitis Kutcher suffered from — severity and length vary by type — or what triggered his case, but most types of the condition are considered rare. Those who have vasculitis often suffer from swelling of the blood vessels that reduces blood flow and may lead to tissue damage.

The most common symptoms include fever, headache and fatigue; depending on the body parts affected, the ailment can also cause ringing in the ears, numbness in the extremities and bleeding in the lungs. Complications from vasculitis can be as severe as blindness or aneurysms.

The causes of vasculitis aren’t fully understood, but medication and infections have been triggers in some cases. The condition can be “short term” or “long lasting,” according to the Mayo Clinic. Corticosteroids are usually prescribed to vasculitis patients to help manage inflammation, though the side effects of long-term steroid use can be significant.

The mystery surrounding the autoimmune disease deepened during the coronavirus pandemic. Health authorities in New York City and in the United Kingdom warned last year of a possible link between COVID-19 and Kawasaki disease, a kind of vasculitis that mainly occurs in young children. The US Centers for Disease Control and Prevention said researchers are trying to learn more about what might trigger the onset of Kawasaki disease, and doctors cautioned against drawing hasty connections.

Complications from the disease killed comedy director, writer and actor Harold Ramis in 2014. Ramis, who appeared in a long list of comedy classics like “Ghostbusters” and “Groundhog Day,” had to relearn how to walk after being stricken with the ailment and died three years after a relapse, the Chicago Tribune reported.