Image copyright Getty Images Image caption Biden’s weight loss and blood clot problems have worried his supporters in recent months
Barack Obama says it was unusual for Barack Obama to require regular hospital visits and a total of 30 sessions with doctors after he became president.
Speaking on the US political site The Upshot, he revealed that his health was a focal point of his 2016 visit to Chapel Hill, North Carolina.
Biden’s health had been monitored closely, and his unusual gait and throat clearing suggested that something was seriously wrong.
He had a blood clot that would eventually cause a stroke, but he is now close to 100% recovered.
Mr Obama did not mention the 18-hour overnight stay in hospital, but said: “Barack, like all of us, will get sick.
“What was unusual was we were monitoring it very closely. We were taking him to hospital on a regular basis just because of concern.”
Mr Obama also said that any concerns of ill health were never at the forefront of Barack Obama’s mind.
“If you think about it, it doesn’t really matter whether you’re healthy,” he said.
“Being president of the United States is a tough job. You’re out there every day dealing with day-to-day issues, it takes a toll.
“And it’s no different for him or for myself.”
He added: “I was always concerned about whether he was well enough to do the job.”
Biden and Obama are in a good place, but both have a lot to look forward to, he said.
“So I think they both are in good health. I’m as impressed by his mind as I am his heart. He is a pretty sharp guy.”