Sir Terry Pratchett has announced he will not attend a conference this summer as a result of his Alzheimer's.
The popular author was diagnosed with posterior cortical atrophy towards the end of 2007, which he has since referred to as "the embuggerance".
He made the announcement on his website, admitting he was "very sorry", but that "the embuggerance is finally catching up with me, along with other age-related ailments".
Sir Terry had been set to make an appearance at the International Discworld Convention in August in Manchester, but with "great reluctance", will no longer attend.
This is the first time the 66-year-old has not been able to be present at a UK convention. Since his diagnosis, he has been a keen supporter of research into cognitive decline, having contributed £500,000 towards this cause.
He was knighted for his services towards literature in 2009 and now, as a result of his condition, dictates his novels as opposed to typing them himself.
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