Columbian author Gabriel García Márquez is suffering from dementia and can no longer write, his younger brother has revealed.

The 85-year-old won the Nobel prize in 1982 and is best known for novels including One Hundred Years of Solitude and  Love in the Time of Cholera. During a lecture in Cartagena, Jaime García Márquez told students that Gabriel, “is doing well physically, but he has been suffering from dementia for a long time.”

The author contracted lymphatic cancer in 1999 and his brother believes cancer treatment has accelerated his mental decline.

“Dementia runs in our family and he’s now suffering the ravages prematurely due to the cancer that put him almost on the verge of death,” Jamie said of his brother last week. “Chemotherapy saved his life, but it also destroyed many neurons, many defenses and cells and accelerated the process.”

Jaime said that he tried to keep his brother’s condition a secret, but decided to make the condition public in order to put an end to damaging rumours.

Jaime said: “The fact is there are lots of comments. Some are true but they’re always filled with morbid details. Sometimes you get the sense they’d rather he were dead, as if his death were some great news.”

He said that while his brother calls regularly to ask very simple questions, “he still has the humor, joy and enthusiasm that he has always had.”

García Márquez’s last novel, Memoirs of My Melancholy Whores, was published in 2007. The book, a short love story about a 90 year old man and a young prostitute, received mixed reviews.

Although he has not published anything in five years, he was said to be writing the second part of his autobiography, Living to Tell the Tale. Jamie told assembled students that he did not think his brother would be able to finish that book.

“Unfortunately, I don’t think that’ll be possible, but I hope I’m wrong,” he said.