Muhammad Ali‘s latest hospital visit is more serious than was expected, officials said.
The 74-year-old boxing legend was hospitalized on Thursday with respiratory issues, his rep told PEOPLE, noting that Ali was in “fair condition” and expected to have a “brief” stay at the hospital.
However, sources familiar with his condition told the Associated Press that Ali’s respiratory issues are complicated by his Parkinson’s disease; the star was diagnosed with the disorder in the 80s.
The sources, who asked to remain anonymous, said Ali’s current condition is concerning to his family members because it seems to be more serious than his previous hospital stays.
Ali was hospitalized in January 2015 for follow-up care after suffering a severe urinary tract infection.
Doctors first believed the infection was a mild case of pneumonia when the former heavyweight champ was hospitalized in December 2014.
“He’s such a fighter, still, when at times he seems weak and not able to handle it,” she said. “He comes through stronger than ever. He’s still fighting regardless and I love my dad for that.”