Here Katie, originally from Glasgow, talks about how cycling helped her take control of her life.
"With hindsight we know I developed epilepsy age three, but I wasn't diagnosed until nine, when I had my first full-blown seizure. Before then I had been having 'petit mal' auras.
The best way I can describe that is as a feeling of sheer fear. It's a bit like being on a ghost train and someone jumping out to give you a fright. But rather than that feeling spiking up and down, it goes up and remains at the same level.
"The day I had my first seizure I was walking upstairs into a classroom when I collapsed. Diagnosed with epilepsy, a lot of trial and error with medication followed. I was on the highest dose for my age group and the unpleasant side effects included nausea and fatigue.
"I had surgery when I was 14 to remove part of my temporal lobe. The operation was successful and afterwards I had five years seizure-free. I joined the police but two years into my career, aged 19, I had was it is termed a 'breakthrough seizure'.
"Epilepsy is a bespoke condition which varies from one person to another so it is difficult to pinpoint what triggered it. It may have been something lying dormant, almost like a volcanic eruption within the brain, then again it may not have been related to anything. Often we don't know why it happens, partly because neurology is still very much a baby science.
"As a result I had to leave the police and give up my driving licence. It meant I had to change direction, but I now see it as a blessing in disguise because otherwise I might not have discovered the freedom which comes from cycling. The bike has been fantastic for making a statement about the condition.
"There is still a stigma about epilepsy. That includes people thinking someone is drunk or on drugs and the belief that they aren't concentrating or staring into space at work while having absence seizures.
"Epilepsy is not a sexy condition and many people give it a wide berth. I have experienced prejudice in job interviews when I have disclosed I have the condition. It can be tough maintaining relationships too, as often people will say 'Cheerio' as soon as you mention it. I find that frustrating.
"I chose to do Race Across America because the solo category is one of the world's toughest endurance sporting events and seemed the perfect way to document my experiences.
"In 2008, aged 22, I was in a four-woman team cycling round the clock: we finished in eight days, six hours and 55 minutes. Next year I plan to do it again in a mixed team, followed by a solo attempt in 2014. To date there hasn't been a British woman complete Race Across America solo.
"Put it this way: if someone with epilepsy can cycle 3000 miles across America, why can't they have a desk job?"
For more information, visit www.epilepsy.org.uk. Katie's blog can be found at cyclingwithepilepsy.blogspot.com
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