Medical Procedure in Childhood Linked to Alzheimer’s Disease Development, Study Finds
A groundbreaking study conducted by researchers from the National Hospital for Neurology and Neurosurgery in London has revealed a potential link between a medical procedure performed on children with growth-related disorders and the development of Alzheimer’s disease later in life. The study suggests that amyloid plaques, which are associated with Alzheimer’s disease, may have been transmitted through injections of a pituitary-derived growth hormone contaminated with brain proteins. While the medical procedure is no longer used due to safety concerns, this discovery raises questions about the possibility of Alzheimer’s disease being transmitted from one person to another.
The research focused on individuals who had received cadaver-derived pituitary growth hormone (c-hGH) between 1959 and 1985 in the United Kingdom. A total of 1,848 people were treated with c-hGH for various growth-related disorders originating in the pituitary gland. Among this population, eight cases were identified where patients exposed to amyloid-beta proteins through the injections developed dementia and biomarker changes consistent with Alzheimer’s disease in their 40s, much earlier than typical cases of dementia.
Amyloid plaques and neurofibrillary tangles of tau proteins are primary markers of Alzheimer’s disease and are believed to contribute to its progression. The study found that these patients not only developed amyloid plaques but also had traces of Creutzfeldt–Jakob disease (CJD) prions, which are known to cause a fatal degenerative neurodegenerative disorder. Previous studies by the same research group had shown that young adults who received c-hGH and later died of CJD also had amyloid deposits in their brains and blood vessels.
The study authors concluded that their research demonstrates the potential for iatrogenic, or acquired, forms of Alzheimer’s disease. They emphasized that while iatrogenic Alzheimer’s may be rare and there is no evidence of casual transmission between individuals in daily activities, it highlights the need to review measures to prevent accidental transmissions through other medical and surgical procedures.
Experts in the field have praised the study for providing real-world evidence of a theory that had previously only been demonstrated in animal experiments. Dr. Claudio Soto, a professor of neurology and director of the George and Cynthia Mitchell Center for Research in Alzheimer’s Disease and Related Brain Disorders at the University of Texas Medical School in Houston, stated that this study opens the door to the possibility of other types of transmission leading to the iatrogenic development of Alzheimer’s disease.
While injections of pituitary-derived growth hormones were discontinued decades ago due to safety concerns, the study raises questions about other potential modes of transmission. Dr. Brian Balin, director of the Center for Chronic Disorders of Aging at the Philadelphia College of Medicine, suggests that iatrogenic transmission of prion diseases has been shown to occur through contaminated surgical instruments. This raises the possibility of transmission through other means such as blood transfusions.
It is important to note that the study does not report that Alzheimer’s disease can be casually transmitted between people. Further research is needed to understand how contamination with amyloid proteins could progress to disease. Dr. Soto emphasizes that there is currently no evidence that people can “catch” Alzheimer’s disease. However, he points out that some prion diseases, such as Bovine Spongiform Encephalopathy (BSE) or “mad cow disease,” can be transmitted through blood.
This groundbreaking study sheds light on the potential for iatrogenic transmission of Alzheimer’s disease and calls for further research to better understand the mechanisms involved. While the medical procedure in question is no longer used, it raises important questions about the possibility of transmission through other medical and surgical procedures. The findings highlight the need for continued efforts to prevent accidental transmissions and protect public health.