A medical treatment last used in the mid-1980s appears to be linked to at least five cases of early Alzheimer’s disease in the United Kingdom, scientists say.
Researchers at University College London have been studying five Alzheimer’s cases linked to injections of human growth hormone that came from deceased donors, according to The BBC.
Researchers stressed that the findings do not mean Alzheimer’s is infectious, meaning you do not “catch” the disease from someone who has it.
In the five cases it’s believed a contaminated hormone may have been “seeded” or transmitted into the brain by certain procedures, The BBC reported.
The people in the study were all treated as children using cadaver-derived human growth hormone, or c-hGH, which was contaminated with brain proteins that are seen in Alzheimer’s disease.
Growth hormone is no longer taken from cadavers. Doctors use synthetic growth hormones now.
The people diagnosed were between ages 38 to 55 years old when they started having neurological symptoms.
Researchers said the unusually young age at which these patients developed symptoms suggests they did not have the usual Alzheimer’s which is associated with old age.
The use of the growth hormone was discontinued when some batches were found to have been contaminated with a different type of infectious protein which had caused a rare and fatal brain condition called Creutzfeldt-Jakob disease (CJD) in some people.
The article published in Nature Medicine suggests Alzheimer’s-related amyloid protein might be spread accidentally during medical and surgical procedures in the same way as CJD.
There have been no other reported cases of Alzheimer’s acquired from any other medical or surgical procedures.
Christopher Weber, director of global science initiatives at the Alzheimer’s Association, said while the study is disturbing, there is no risk to the general public.
“Alzheimer’s disease is not contagious,” Weber told NBC News. “You can’t catch Alzheimer’s by taking care of someone with Alzheimer’s. Alzheimer’s disease is not transmissible through the air, or by touching or being near someone with Alzheimer’s,” Webber said.
Lead author Professor John Collinge, director of the UCL Institute of Prion Diseases, told the BBC “There is no suggestion whatsoever that Alzheimer’s disease can be transmitted between individuals during activities of daily life or routine medical care.
“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.”