Glenn shared a photos of himself in a hospital bed at the Intermountain Medical Center in Murray, Utah.
As of Monday, the 36-year-old singer said that he didn't know what caused the stroke and only noticed a medical problem when he couldn't see clearly out of his right eye. He waited a day before seeing an ophthalmologist, who told Glenn that he had "retinal edema" and needed to go to a hospital.
"It wasn’t just an eye floater like I’d presumed and hoped. He informed me I had had a stroke, and that I should immediately go to the hospital. There I was admitted and began a series of tests, every cardiology and neurological test they could do, my last test being (Monday) morning," Glenn wrote.
People older than 65 are much more likely to have a stroke than younger adults. Around 10% of strokes happen to people who are younger than 45, according to Standford Medical Center.
Glenn urged his fans to seek medical treatment if they do not feel well.
"If you ever feel or experience something in your body that feels off, please don’t wait to get it checked out. You always assume it can’t happen to you, until it does," he wrote.
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