Legendary singer Tony Bennett is battling Alzheimer’s disease, his family has revealed publicly for the first time.

The 18-time Grammy winner’s condition was first reported Monday morning in AARP the Magazine. Bennett, 94, was diagnosed with Alzheimer’s in 2016, his family said.

Alzheimer’s disease is a progressive neurologic disorder and the most common cause of dementia. Memory loss related to the disease may include recent events, family members’ names and everyday objects. 

Bennett’s wife, Susan Benedetto, says Bennett, whose career began in the 1940s, is not in any pain, can still recognize family members and has not exhibited the sort of mood swings sometimes associated with Alzheimer’s. But the crooner is not always sure what is happening around him and some objects, such as a fork or house keys, can seem mysterious to him, Susan told AARP. 

He also still rehearses twice a week at his Manhattan apartment and remembers all the lyrics. 

"No cue cards," Benedetto said in a separate interview with CBS News. "He sings for about an hour or 75 minutes. Sings the whole show because if somebody calls up and says, 'Hey, there’s a theater, you can come sing,' he’ll be ready."

His wife said Bennett is his most lucid when he’s singing.

"He's devoted his whole life to the great American songbook," Susan told CBS News. "And now the songbook is saving him."

Susan said it was Bennett himself who first noticed there was a problem. After he couldn’t remember the names of the musicians he was performing with during a 2015 show, he asked to see a doctor. He was diagnosed with Alzheimer’s shortly after.

But today, the "I Left My Heart in San Francisco" singer doesn’t recognize there is anything wrong with him, his wife said.

Dr. Gayatri Devi, the New York neurologist who diagnosed Bennett, told AARP that the singer "brought an amazingly versatile brain" and has some "cognitive issues, but multiple other areas of his brain are still resilient and functioning well. He is doing so many things, at 94, that many people without dementia cannot do. He really is the symbol of hope for someone with a cognitive disorder."

Susan said Bennett’s doctor believes there is no reason to think that he will drastically decline.

Bennett’s family decided to break their silence about his condition because they knew he couldn’t do interviews to promote his forthcoming second album with Lady Gaga, which they began recording two years after his diagnosis. Susan and Bennett’s son/manager, Danny, were eager for people to hear it and enjoy what could be Bennett’s last record., 

"He always likes to say he’s in the business of making people feel good," Susan told CBS News. "And so he never wanted the audience to know if he had a problem, but obviously, as things have progressed, it becomes more and more obvious when you interact with Tony that there’s something up."