Cats With Dementia Show Brain Changes Mirroring Alzheimer’s in Humans, Study Finds

Cats suffering from dementia experience brain changes strikingly similar to those seen
in people with Alzheimer’s disease, according to new research that could provide
scientists with a valuable model for studying the condition in humans.

The study, led by researchers at the University of Edinburgh, found a build-up of the
toxic protein amyloid-beta in the brains of affected cats – one of the defining hallmarks
of Alzheimer’s in humans. The protein accumulated within the synapses, the vital
junctions that connect brain cells and enable them to communicate.

Amyloid-beta is widely believed to play a key role in age-related brain decline. In
Alzheimer’s, its accumulation is linked to the progressive loss of synapses, a process
that strongly predicts memory loss and reduced cognitive function.

Scientists examined the brains of 25 cats of various ages that had died, including
several that had shown signs of dementia during life. The team used high-powered
microscopy to capture detailed images of the brain tissue, revealing clear amyloid-beta
deposits in the synapses of both older cats and those diagnosed with dementia.

Feline dementia, also known as cognitive dysfunction syndrome, is common in older
cats. Symptoms include increased vocalisation – often excessive meowing –
disorientation, changes in interaction with owners, and disrupted sleep patterns. These
behaviours bear a strong resemblance to the confusion, restlessness and memory loss
observed in people with Alzheimer’s disease.

Researchers say the findings not only deepen understanding of dementia in cats, but
also offer a non-invasive way to study the earliest changes in Alzheimer’s. By identifying
how amyloid-beta accumulates and disrupts communication between brain cells,
scientists hope to develop better treatments and prevention strategies for both species.

The study adds to growing evidence that age-related neurological diseases may share
common biological mechanisms across mammals, underscoring the value of veterinary
research in tackling some of the most challenging conditions in human medicine.