Robin Williams was in the early stages of Parkinson’s Disease — but was not ready to share that information publicly — when he took his own life, his wife said Thursday in a statement, adding that he died with his sobriety “intact.”

Parkinson’s is a degenerative central nervous system disorder that causes tremors, stiffness and slowing of movement over time, and severe depression — for which Williams had been seeking treatment — is one of its most common psychiatric symptoms. Michael J. Fox and Muhammad Ali both suffer from Parkinson’s, which can be controlled to varying degrees by medication.

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The entire statement, from Susan Schneider:

Robin spent so much of his life helping others. Whether he was entertaining millions on stage, film or television, our troops on the frontlines, or comforting a sick child — Robin wanted us to laugh and to feel less afraid.

Since his passing, all of us who loved Robin have found some solace in the tremendous outpouring of affection and admiration for him from the millions of people whose lives he touched. His greatest legacy, besides his three children, is the joy and happiness he offered to others, particularly to those fighting personal battles.

Robin’s sobriety was intact and he was brave as he struggled with his own battles of depression, anxiety as well as early stages of Parkinson’s Disease, which he was not yet ready to share publicly.

It is our hope in the wake of Robin’s tragic passing, that others will find the strength to seek the care and support they need to treat whatever battles they are facing so they may feel less afraid.

The revelation in part helps explain why someone as vibrant, beloved and successful as Williams would choose to take his own life.

It also completes the profile of a group whose risk for suicide has spiked alarmingly in recent years: Middle-aged white men at the end of a successful career who have a history of chronic depression, substance abuse — and a serious medical condition.

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