A study published in Nature Medicine reveals Alzheimer's disease can be transmitted between humans through rare medical procedures.

Alzheimer's disease is believed to be acquired through the transmission of a harmful protein from deceased donors.

A few individuals who received human growth hormone from deceased individuals developed early-onset Alzheimer's disease due to contaminated proteins in the hormones.

The study supports the idea that Alzheimer's shares similarities with prion disease, which is caused by infectious proteins that misfold and spread within the brain.

The study documented the administration of human growth hormone derived from cadaver pituitary glands to a minimum of 1,848 patients in the UK from 1959 to 1985.

 The study also found that administering these hormone batches to mice resulted in the onset of a disease similar to Alzheimer's.

The researchers acknowledged the uncertainty regarding whether these patients would eventually exhibit symptoms of Alzheimer's disease.

The study's findings should prompt reassessment of preventive measures against inadvertent transmission through alternative medical or surgical procedures.