A study published in the journal nature medicine explored the possibility of human transmission of Alzheimer’s disease (AD) pathology through a medical procedure that has been discontinued decades ago. The group of English researchers investigated eight individuals who received childhood treatment with cadaver-derived pituitary growth hormone (c-hGH). Background of this recent investigation is previous research by the team where they reported on the human transmission of Aβ pathology and cerebral amyloid angiopathy in relatively young adults who had died of iatrogenic Creutzfeldt–Jakob disease after childhood treatment with c-hGH. In their most recent study, they reviewed eight individual cases who were treated with c-hGH some decades ago but did not develop Creutzfeldt–Jakob disease.
Five out of these eight individuals developed early-onset dementia between the ages of 38 and 55. In three of these cases, AD was already confirmed prior to the referral to the National Prion Clinic (The National Prion Clinic (NPC) forms part of the United Kingdom national referral system for suspected prion diseases). Each showed different symptoms, fitting the criteria for probable AD. Among the last three people studied; one showed symptoms of mild cognitive impairment; one had subjective cognitive symptoms and the other was asymptomatic. The time from c-hGH exposure until symptoms appeared was between 30 and 40 years. The researchers emphasize that AD caused by medical procedures is rare and there's no evidence of transmission through everyday activities. However, they suggest revisiting safety measures of medical procedures to prevent any accidental transmission.
