MEXICO CITY — Apple co-founder Steve Wozniak remained hospitalized Thursday in Mexico City for “medical issues” while in the city to speak at a business conference, said a source close to the conference, who spoke on condition of anonymity because they were not were authorized to speak about the event.

Wozniak, 73, was scheduled to speak at the World Business Forum in Mexico City, a two-day gathering considered the world’s premier management event. Other advertised speakers included Carly Fiorina, the former CEO of Hewlett-Packard, and Muhammad Yunus, a microfinance pioneer who won the Nobel Peace Prize.

The gregarious Wozniak, who co-founded Apple with the late Steve Jobs in 1976, was scheduled to be the closing speaker at the conference on Wednesday afternoon.

Wozniak had a “medical issue” shortly before he was due to arrive at the event, said the source, who declined to specify what the issue was.

“My understanding at this time is that he is stable,” the source said, adding that information about his status had come from family members.

ABC Santa Fe Hospital, where Wozniak was taken, said it would not release any information.

Wozniak left Apple in 1985 to pursue a number of other interests, but remained an ardent advocate for the company and a technology evangelist. More recently, he has pursued many other interests, including competing on “Dancing With The Stars” in 2009 and serving as a judge on an online video show called “Unicorn Hunters,” which evaluates the ideas of entrepreneurs competing to build startups, potentially worth $1 billion or more.

While working on other startups, Wozniak also helped keep alive the memory of his longtime friend Jobs, who died of cancer in 2011.