By Stephen Hanks, Contributing Reporter

The Alzheimer’s disease research community received a jolt last Thursday when a new study revealed the possibility that Alzheimer’s might be transmitted to humans during certain medical procedures.

The recent findings of researchers from the University College London (UCL) and published in the September issue of Nature Magazine, suggest that people who died of Creutzfeldt-Jakob disease (CJD) — a rare but deadly neurodegenerative disease caused by the presence of an abnormally folded protein called a “prion” — contracted CJD decades after treatment with contaminated human growth-hormone (hGH).
Between 1958-1985, tens of thousands of people worldwide were treated with growth hormone that had been extracted from the pituitary glands of human cadavers that were contaminated with CJD prions.

During autopsy studies, the UCL team examined eight brains and found that in six there was evidence of the amyloid pathology (insoluble fibrous protein) that is associated with Alzheimer’s and other diseases such as Parkinson’s and Huntington’s.

“This is the first evidence of real-world transmission of amyloid pathology,” UCL molecular neuroscientist John Hardy told Nature. “It is potentially concerning.”

The eight people analyzed in the autopsy study were between 36-51 when they died. None possessed any clinical symptoms or family history of Alzheimer’s, nor did they carry genes that predisposed them to Alzheimer’s or any other neurodegenerative diseases. Yet, in four of the six brains, the amyloid peptide was widespread.

When the researchers examined patients of similar age who had died of CJD or other prion diseases but who had not been treated with hGH, no evidence of amyloid pathology was observed.

Before anyone becomes concerned that they might contract Alzheimer’s by direct contact or through medical procedures, such as blood transfusions or contaminated surgical instruments, the UCL researchers said their findings are not conclusive and that people cannot get Alzheimer’s by coming into contact with people who have the disease.

“While the findings sound concerning, it’s important to remember that human-derived hormone injections are no longer used and were replaced with synthetic forms since the link to CJD was discovered in the 1980s," said Eric Karra, director of research at Alzheimer’s UK, in an article from the BBC.

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