Robin Williams was in the early stages of Parkinson’s disease when he took his own life in his San Francisco-area home earlier this week.  His wife Susan Schneider said that he as not ready to share that in public yet, and it's not known how long ago the diagnosis was made.

Williams was also dealing with anxiety and depression, which he had been quite open about over the years, but Schneider insisted her husband’s persistent demon – his sobriety – was “intact”.

“His greatest legacy, besides his three children, is the joy and happiness he offered to others, particularly to those fighting personal battles,” Ms Schneider said in a statement.  “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.”

Parkinson’s is a degenerative neurological disorder which afflicts some five million people, and whose cause is known.  Symptoms can include tremors and other uncontrollable movements, impaired balance and co-ordination, and a decline in speech and intellectual functions. 

The 63-year old actor and comedian was found by his assistant on Monday.  Authorities said the cause of death was asphyxia due to hanging.