“Very rare” cases of transmissible Alzheimer’s disease identified

New research, published today in Nature Medicine, has identified five cases of Alzheimer’s disease believed to have arisen because of a medical treatment decades earlier. These individuals had all been treated as children with a type of human growth hormone extracted from pituitary glands from deceased donors (cadaver-derived human growth hormone or c-hGH). This treatment has been banned since the 1980s due to concerns that it was responsible for transmitting Creutzfeldt-Jakob Disease (CJD).

In their new study, researchers based at UCL and UCLH found that the growth hormone had the potential to contain fragments of amyloid – a hallmark protein of Alzheimer’s. Five people treated with this had gone on to develop symptoms of the disease, which was confirmed with diagnostic tests.

The team ruled out other potential causes of these symptoms, such as genes linked to young-onset Alzheimer’s, and whether having a growth hormone deficiency itself was linked to Alzheimer’s development.

“This transmission occurred following treatment with a now obsolete form of growth hormone, and involved repeated treatments with contaminated material, often over several years” said Dr Gargi Banerjee, an Alzheimer’s Research UK Clinical Research Fellow who was part of the study’s research team.