A teenager in China has been diagnosed with Alzheimer's disease, making him the youngest person in the world ever to receive such a diagnosis, according to a report by Science Alert. The boy, who was 19 at the time of diagnosis in 2022, was seen by neurologists at a memory clinic in China. He had first begun struggling with memory loss around the age of 17, with his condition gradually worsening over the following years.
Brain scans showed shrinkage in the hippocampus, the region of the brain responsible for memory, while tests of his cerebrospinal fluid revealed biomarkers consistent with Alzheimer's disease, the most common form of dementia, according to Science Alert.
Two years before being referred to the clinic, the teenager had begun finding it difficult to concentrate in class. Reading became a struggle, and he frequently could not recall events from the previous day or remember where he had left his belongings. His condition deteriorated to the point where he was unable to complete his secondary school education, though he remained able to live independently.
His memory test scores were dramatically below those of his peers, with his full-scale memory score 82 per cent lower and his immediate memory score 87 per cent lower than average.
What makes the case particularly baffling is that no genetic mutations typically linked to early-onset Alzheimer's were found, despite a thorough genome-wide search. None of his family members had any history of dementia either.
The previous youngest known Alzheimer's patient was 21 years old and carried a specific gene mutation called PSEN1, which causes toxic protein plaques to build up in the brain.
Neurologist Jianping Jia and colleagues, who published the case study in the Journal of Alzheimer's Disease, said the patient was "altering our understanding of the typical age of onset" of the condition. They called for further research into young-onset cases, describing it as one of the most challenging scientific questions of the future.
