BEST-SELLING author and former Bucks Free Press reporter Terry Pratchett has revealed his Alzheimer's disease is causing him to cut down on public appearances.

The popular novelist, who was born and raised in Beaconsfield, left a message for his fans, on www.paulkidby.com, the website of his illustrator.

He said: "I shall very soon be on medication that in theory should blow some of the cobwebs away and I hope my typing speed and accuracy will improve.

"I regret to say that I'm even cutting down on answering fan mail because my typing is so slow."

Despite the news, the website shows the author of the Discworld is due to attend an engagement this month to celebrate 25 years since the release of the series.

He also said that he will be setting up a fund so that fans can donate to Alzheimer's Research Trust.

In December the writer announced he was suffering from a rare form of early onset Alzheimer's disease.

He worked as a reporter and sub-editor at the Bucks Free Press during the 60s and 70s, before embarking on a career as a novelist.