Actor Alan Alda announces he has been battling Parkinson's disease since 2015

Six-time Emmy-award winner Alan Alda announced that he has Parkinson’s disease - and has been battling the disorder since he was diagnosed in 2015.

Alda, best known for starring in the American comedy-drama M*A*S*H as combat doctor Hawkeye Pierce, revealed his diagnosis in an interview with CBS This Morning, where he discussed the “full life” he’s lived since then.

“I was diagnosed three-and-a-half years ago and I’ve had a full life since then,” the 82-year-old said. “I’ve acted, I’ve given talks, I help at the Alda Centre for Communicating Science at Stony Brook, I’ve started this new podcast.”

The award-winning actor decided to reveal his diagnosis after he noticed during a TV appearance that his thumb was twitching.

“I thought it’s probably only a matter of time before somebody does a story about this from a sad point of view, but that’s not where I am,” he said.

On the 82-year-old’s new podcast Clear+Vivid, he explores the various ways in which people communicate - a key to greater understanding, according to Alda.

It was the podcast - and his dedication to his communication centre which teaches acting techniques and communication skills - that encouraged Alda to publicly reveal his diagnosis.

Although he admits that in the very beginning there is fear, he said you have to remember it hasn’t “happened to you. You still have things you can do,” revealing that he engages in boxing and tennis lessons multiple times a week. He also marches to "Sousa music because marching to music is good for Parkinson's."

Parkinson’s is a neurodegenerative disorder that results in loss of control over “motor” functions. Symptoms, which can develop over years, typically include body tremors and difficulty walking.

The disease affects 10 million people worldwide, according to the Parkinson’s Foundation.

By revealing his own battle, Alda wants others diagnosed with Parkinson’s to maintain hope and “keep moving” - while putting his own mind at ease.

“I’m not going to worry,” the 82-year-old said. “It hasn’t stopped my life at all. I’ve had a richer life than I’ve had up until now.”