If it has only been 6 years, and it was £80 then, it would mean that the prices have increased by 12% per year, which is high. I don't think inflation in the rest of the economy has been any where hear 12%.
So, either it wasn't £80 6 years ago, or the price hike is exorbitant, or (more likely) the tests and processes required have changed and the doctor is now required to expend more for the exam than before.