The music icon added that she plans to return to stage one day, "even if I have to crawl"
When Céline Dion started experiencing the debilitating symptoms of what would doctors would later understand as the effects of the rare autoimmune and neurological disorder stiff-person syndrome, she had to find a way to move forward.
"I went on stage and I started to sound more nasal," the legendary music star recalled to Hoda Kotb in a NBC News interview previewed on the Today show on Tuesday, June 11. "I could say, 'it's a little cold starting' or 'it's the third show in a row.' 'You're working too hard.' But the thing is, it was different. I started to feel like the body was more rigid."
Dion was on the 2008 Taking Chances World Tour at the time. It was a stop in Germany when her health issues came to ahead. "I said to my assistants and to my people, 'I don't know if I can do the show,' " she said. "I was very, very, very scared. And then you panic, and the more you panic, the more you spasm."
Related: Céline Dion Describes the Effect Stiff-Person Syndrome Has on Her Voice: 'Like Somebody's Strangling You'
Those spasms are one of the key conditions of stiff-person syndrome, alongside things like slurred speech and double vision. The painful muscle contractions can become so severe that patients can lose their ability to walk or speak. In Dion's case, she said "it's like somebody is strangling you. It's like somebody is pushing your larynx/pharynx."
"When I try to breathe, my lungs are fine. It's what's in front of my lungs that's so rigid," Dion explains in her new Prime Video documentary I Am: Céline Dion, footage of which aired on Today.
Afraid to disappoint her fans, Dion powered through her health troubles on the Taking Chances World Tour. She told Kotb she "compensated" by adjusting the songs to a different register.
"We lowered the songs a little bit with the keys," Dion said, noting that she relied on "hope" to carry her through. "I did my very best because my fans accepted my invitation and I did not know what to tell them. 'I will do my best tonight?' No. You're going to give your all or you don't come at all."
Related: Céline Dion Reveals Why She Shared Stiff-Person Syndrome Diagnosis: 'Lying for Me, the Burden Was Too Much'
Though Dion still received praise from concertgoers, she knew she wasn't 100%. "Everybody [said], 'You look pristine,' " Dion remembered. But I was not controlling [my voice] anymore and I want to be controlling."
Eventually, after over a decade of testing and canceling both a planned Las Vegas residency and tour dates in late 2021 and 2022, Dion was given her official diagnosis. She'd go public with her health issues in December 2022, when she announced in an Instagram video that she was postponing a number of performances.
Her new documentary chronicles the Grammy-winning icon as she grapples with her rare disorder and fights to get back on stage. She told Kotb that she plans on making that return no matter what.
"I spent all my life in the music industry being a performer and loving every moment of it. This passion will never go away," said Dion. "I'm going to go back on stage, even if I have to crawl, even if I have to talk with my hands. I will. I will. ... Not just because I have to or I need to, but because I want to. I miss it."
Related: Céline Dion Says Her Sons Fuel Her to Fight Stiff-Person Syndrome: 'They Already Lost a Parent' (Exclusive)
And while Dion has that drive insider her, she tells PEOPLE she finds strength in (and for) sons René-Charles, 23, and 13-year-old twins Nelson and Eddy -- whom she shared with husband René Angélil before his death from throat cancer in 2016.
"I let them know, 'You lost your dad, [but] mom has a condition and it's different. I'm not going to die,' " Dion recalls in PEOPLE's latest cover story (on stands Friday, June 14). "'It's something that I'm going to learn to live with.' "
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Dion's interview with Kotb will air in full on Tuesday, June 11, at 10 p.m. ET. I Am: Céline Dion premieres on Prime Video on June 25.
