'I raged at God over this Alzheimer's.. but I've never felt so alive, I'm so angry' EXCLUSIVE: AUTHOR TERRY PRATCHETT ON HIS FIGHT.

Byline: By ALUN PALMER

EVERY morning, best-selling millionaire author Terry Pratchett sits in front of his computer and fights to recognise the letters in front of him.

His fingers hover over keys and moments pass as he searches to find the first letter of the day.

It is, he says with typical comic understatement, bloody annoying.

"But it will get worse," he admits. "How it will get worse I don't know. It's a struggle to type. If I let the auto-pilot take over it works and everything is fine. I have a good idea where most of the letters are, I just have to find them."

Four months ago Pratchett, whose fantasy Disc-world novels are loved by millions, was diagnosed with a rare form of early onset Alzheimer's Disease.

It hasn't stopped him working yet though. He has just finished one novel and started work on a new Discworld book called Unseen Academicals. And Sky is screening an adaptation of his book A Colour Of Magic starring David Jason and The Lord Of The Rings star Sean Astin at Easter.

Yesterday we revealed that Pratchett is giving pounds 500,000 to the Alzheimer's Research Trust charity to back its work in finding treatments. But he doesn't expect a cure to be found within his lifetime.

Each day, he admits, the Alzheimer's strips away his living self a bit at a time. In his first interview since diagnosis, the author, who has sold 55 million copies worldwide and who was Britain's best-selling author in the 90s, reveals: "The Alzheimer's at the moment is a nuisance. If it didn't get any worse that would be very good."

But although he seems relaxed and resigned to his fate, the 59-year-old has his darker moments too. "I raged at God and I don't believe in him. But I might change my mind as atheism lets him off the hook," he says. "I had this pure anger at everything... but I've never felt so alive."

Anger that he cannot die in his late 80s like his father. Anger at a government that makes it hard for sufferers to get Aricept, the one drug that may help the condition. And anger that so little research is done into a disease affecting 700,000 in the UK.

Aricept costs only pounds 2.50 a day and can slow the progression of the disease so sufferers can lead a normal life longer. But NHS rules say it should only be prescribed to those with more severe Alzheimer's.

At first Pratchett, whose ardent fans sometimes copy his trademark skull ring to exchange at their weddings and who is the UK's most shoplifted author, put his absent-mindedness down to "senior moments".

"People laugh about senior moments - about forgetting names and losing things," he says. "But it's like wearing a balaclava helmet under my skin."

At first doctors thought he'd had a mini-stroke. But a scan at Addenbrooke's hospital in Cambridge revealed he has a form of Alzheimer's in part of the brain rarely linked with the disease.

"Authors are self-obsessed, irritable, absentminded manic depressives. The range of things you associate with dementia you associate with writers - it was only with the tests last November that I knew I had it," he explains. His wife of 40 years, Lyn, and their daughter Rhianna, 32, have been by his side throughout, supporting him. "My first thought was, 'it could be worse, it could be my wife'," he says. "As a married man, that's how you think. My wife thought 'that's a relief, I thought it was a tumour'. But people survive tumours.

"Lyn has been wonderful. She watches me like a hawk. If I knock a spoon off the table she leaps, but I say 'It's OK, I've just knocked a spoon off the table. It's not the Alzheimer's'. She is very careful about what I eat. At the moment I need no more care than any husband."

And Pratchett has no plans to die yet. But euthanasia is something the humanist had accepted long before he was diagnosed. "My view is that when there is clearly no 'me' left, whatever else might be left, then painlessly disposing of the remnants would be a sensible idea," he says.

Since announcing he had the disease on his website, he has been inundated with support from fans and emails have flooded in from Alzheimer's sufferers sharing their experiences.

And despite his struggle Pratchett is determined to keep writing. Plots and characters still come easily to him.

The difficulty now is getting them from his mind on to the page. "My plan is to do two more books," he says. "I believe that should be possible and hope I will do more. But the moment it becomes physically difficult and too problematic then well...

"I have a nice house, nice garden and lovely places to walk. Maybe retirement isn't such a bad idea.

"If a fairy waved a magic wand and said that's it, you can stay at this level for a long time I would not feel hard done by. I could be here for another 20 years - you just don't know. If I could still be going to the pub in 20 years, that would be fine by me. There is everything to play for."

.AN auction of Sky's Colour Of Magic prop The Luggage, filled with books signed by Pratchett and the cast plus other memorabilia, is being held on eBay. All proceeds go to the Alzheimer's Research Trust.

pounds 11

the amount spent on research per person .. pounds 289 for cancer

25 MILLION

people worldwide with the disease

39,400

diagnosed with it every year in this country

5 YEARS

Patients live 5 to 7 years on average

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CAPTION(S):

GOTHIC: Pratchett's trademark skull ring; SPEAK OUT Millionaire author Terry Pratchett Picture: MIKE MOORE; PILLAR OF STRENGTH: With his wife of 40 years, Lyn; ME AND MY GIRL: With Rhianna