Alzheimer’s Disease can be passed to humans treated using hormones extracted from corpses, scientists have found.
Researchers have discovered that five people treated with human growth hormone (HGH) extracted from corpses received a tainted batch that led them to develop dementia.
The tainted supply was given to nearly 2,000 children of short stature in the UK over nearly 40 years between 1959 and 1995.
Use of the hormone to assist with growth was discontinued in 1995 after it was found to be a trigger of Creutzfeldt-Jakob Disease (CJD).
Scientists at University College London (UCL) have discovered that the same batch appears to have triggered Alzheimer’s in a number of those patients, one of whom developed symptoms as young as 38.
More than 1,800 people received the hormone between 1959 and 1995, and scientists from UCL believe that five of them – aged between 28 and 55 – developed symptoms of Alzheimer’s.
Researchers found those five were not at genetic risk of the condition, but study authors were keen to stress this does not mean Alzheimer’s can be “caught”.
Professor John Collinge, director of the UCL Institute of Prion Diseases and lead author of the study, said the study’s findings do not mean carers or relatives of Alzheimer’s patients can catch the disease.
He said: “We are not suggesting for a moment you can catch Alzheimer’s disease. You can’t catch it by being a carer or living with a husband or wife with the disease.”
“The patients we have described were given a specific and long-discontinued medical treatment which involved injecting patients with material now known to have been contaminated with disease-related proteins.”
Professor Collinge added that recognising the transmission in these “rare situations”, should allow scientists to review measures that might prevent accidental transmission in other medical settings.
The scientists initially discovered the transmission by accident in a separate study of people who died of CJD after receiving human growth hormone.
They found that four people had significant levels of amyloid beta protein – a substance that develops among brain cells and prevents them from communicating efficiently.
None of them developed dementia, but scientists believe they likely would have, had they not died from CJD.
The researchers were later able to get their hands on the original growth hormone they received from a Department of Health storeroom, and, after injecting mice with the substance, found they developed signs of Alzheimer’s.
They concluded that the hormone contained misfolded amyloid-beta proteins implicated in Alzheimer’s.
