Stan Bowles, the former England and QPR forward, has been diagnosed with Alzheimer's disease.
The 66-year-old was recently voted the London club's greatest ever player by supporters.
A statement released by Bowles' family on his Facebook page on Saturday read: "We are writing this on behalf of our father Stanley Bowles.
"We would like it to be known that our father has unfortunately developed a form of Alzheimer's. Consequently he finds it extremely difficult to sign autographs etc.
"We would be grateful for anyone who comes into contact with our father to show some understanding of his condition.
"We have, on behalf of our father, been grateful that fans still show interest in him and would be grateful that anything regarding him is played low key.
"We will continue his Facebook page and hope you will continue to share your memories. Thanking you in anticipation".
Bowles, capped five times by England, began his career at Manchester City before going on to play for Bury, Crewe, Carlisle and then QPR.
He then had stints at Nottingham Forest and Leyton Orient before ending his career in 1984 after a three-year stint at Brentford.
QPR tweeted: "The thoughts of everyone at the club are with Stan Bowles following confirmation that he has developed a form of Alzheimer's."
