The writer, broadcaster and agony aunt failed to recover after undergoing emergency intestinal surgery in May, PA reports.
Claire passed away yesterday in hospital near her home in Harrow, north-west London. She is survived by her husband of 53 years Des, her three children and four grandchildren.
Des said: "I have lost my best friend and my soulmate. I am immensely proud of her. Through her own approach to life she enabled people to talk about their problems in a way that was unique.
"Right up until her death she was being consulted by both politicians and the medical profession about the best way to provide the health services the nation deserved and nothing mattered to her more than that. Her death leaves a vacancy which will not be filled."
Over the weekend, the former nurse and patients' rights campaigner told her family that she wanted her last words to be: "Tell David Cameron that if he screws up my beloved NHS I'll come back and bloody haunt him."
Claire will be given a humanist funeral service for close friends and family only.
