Parkinson's disease: What to know about Neil Diamond's diagnosis

Neil Diamond announced Tuesday that he is retiring from touring due to his recent diagnosis of Parkinson's disease.

"The onset of the disease has made it difficult to travel and perform on a large scale basis," a spokesperson said, according to CBS Los Angeles. "Based on his doctors' advice, the third leg of Diamond's 50th Anniversary tour, set to land in Australia and New Zealand this March, has been cancelled."

The Rock and Roll Hall of Famer, known for numerous hits including "Sweet Caroline," ''America," ''Love on the Rocks" and "Hello Again," was on his 50th anniversary tour and cancelled dates in Australia and New Zealand for March.

Diamond turns 77 on Wednesday and will get the lifetime achievement award at Sunday's Grammy Awards.

What is Parkinson's disease?

Parkinson's disease is a disorder of the central nervous system that affects movement, often causing tremors.

Estimates vary, but about 50,000 people are diagnosed with Parkinson's in the United States each year and about half a million people have the disease, according to the National Institutes for Health.

While a tremor is perhaps the most recognizable symptom of Parkinson's, the disease can also cause stiffness, slowed movement and speech changes.

What causes Parkinson's disease?

The cause of Parkinson's is unknown but scientists believe several factors play a role, including genetics, environmental triggers and other health conditions.

According to the Mayo Clinic, researchers have identified specific genetic mutations associated with Parkinson's disease, though these are rare unless many family members are affected by the disease.

The presence of Lewy bodies -- clumps of specific abnormal proteins -- also appear to be markers of Parkinson's disease. Scientists are working to better understand their relationship to the disease.

Additionally, research has also shown that exposure to toxins, including herbicides and pesticides, may slightly increase the risk of Parkinson's.

Men are also more likely to develop Parkinson's than women. People typically develop the disease around 60 or older.

How is Parkinson's treated?

Currently, there is no known cure for Parkinson's disease, but a variety of medications can provide relief from symptoms.

Parkinson's is a both a chronic and progressive disease, meaning it persists over a long period of time and symptoms grow worse over time. Some people become severely disabled, while others may experience only minor motor disruptions. At this time, doctors are unable to predict which symptoms will affect an individual or how intense they will be throughout a person's life.