Domestic cats show age-related patterns of brain deterioration comparable to those in humans, possibly offering new opportunities for studying human ageing and related diseases, according to a new study.
Shorter lifespans of cats mean factors affecting ageing can be studied at a much faster rate in cats than in humans, scientists from the University of Bath in the UK, Auburn College of Veterinary Medicine in the US and National Veterinary School of Toulouse in France said.
Currently, research relies on laboratory animals, where diseases are artificially induced and lifespans are limited, the researchers said.
The team looked at 3,754 data points collected across humans, cats and other mammalian species, covering brain imaging, blood chemistry and disease-related patterns. The data points also pertained to behavioural milestones such as eye opening and the onset of playful behaviour.
“Cats may serve as valuable models for human ageing because there is some evidence that they can develop human-related ageing patterns,” the authors wrote in the study published in the journal Biology Open.
Structural magnetic resonance scans from pet and colony cats helped quantify age-related brain metrics during ageing, including overall shrinkage, expansion of the ventricles (the hollow spaces inside the brain filled with fluid), and other alterations.
“Cat and human brains exhibit similar age-related patterns of brain atrophy. We used common patterns of brain change and other health-related metrics to generate age alignments across the lifespan to late stages of life (eg an 80-year-old human equates to a 15-year-old cat),” the authors said.
The brain changes are found in conditions commonly associated with ageing. Both humans and older cats can develop age-related neurodegenerative changes later in life.
“It was interesting to see that cats show patterns of age-related brain atrophy similar to those observed in humans. These findings add to growing evidence that companion animals can provide valuable insights into ageing,” lead researcher and author Brier Rigby Dames, from the University of Bath, said.
The researchers developed a biological model based on measurable age-related changes, revealing that ageing in both the species does not progress at a constant rate but instead speeds up or slows down at different life stages.
The team found that a cat in its mid-teens corresponds to a human in their 80s.
Further, ageing patterns later in life align particularly closely between the two species and not all animals reach the equivalent of human old age, but domestic cats do.
Co-author Dr Ryan Gibson, a veterinary neurologist at Auburn University’s College of Veterinary Medicine, said cat owners are increasingly requesting advanced brain imaging for pets to diagnose disease, providing an opportunity to study ageing animals living alongside humans in real-world environments.
Rigby Dames said, “There’s potential to develop large-scale veterinary health databases for companion animals, analogous to human health databases such as the UK Biobank. These kinds of resources could enhance our ability to study ageing and disease using real-world clinical and owner-reported data collected across species."
