What does a healthy ageing cat look like?
Just as improved diet and medical care have resulted in increased life expectancy in humans, advances in nutrition and veterinary care have increased the life span of pet cats.
The result is a growing population of ageing cats; in the USA, for example, it is estimated that 20% of pet cats are 11 years of age or older.
According to the charity International Cat Care, cats reach the ‘geriatric’ life stage at the age of 15 (the equivalent of 76 years in human terms), but it is not unusual for them to live to late teens and even into their 20s (a cat becomes the equivalent of a centenarian at 21 years old). Fortunately, for these feline golden oldies, which are often cherished family members, it is now generally accepted that ‘healthy ageing’ is achievable; just as it is in humans where the field of ageing wellness is dedicated to optimising mental, social and physical wellbeing and function in older adults. What has been less well defined, however, is what healthy ageing actually looks like in a cat; in other words, what changes would be considered ‘normal for age’ (ie, physiological changes) as opposed to deteriorative changes.
The hair coat of older cats may take on a clumped and spiked appearance associated with a reduction in grooming activity.
To answer this question, a groundbreaking special issue of the international, peer-reviewed Journal of Feline Medicine and Surgery (JFMS) has been published devoted to the subject ‘feline healthy ageing’. Comprising two comprehensive systems-based reviews written by a distinguished group of experts, it collates information on common changes observed in cats in a wide range of health areas of interest – from musculoskeletal system health through to cognitive and behavioural health. The authors’ aim throughout has been to support health and wellbeing in the ageing animal.
As well as reviewing the available data in cats, the authors have discussed resources used in other species that have application in cats. For example, in terms of cognitive abilities, they define a healthy aged cat as one that shows none of the so-called ‘DISHA’ pattern of signs described in dogs; namely disorientation, interaction changes, sleep/wake disturbances, house-soiling and changes in activity. The authors have also developed new resources, such as serum biochemistry and complete blood count reference intervals specifically for mature to geriatric cats, which were generated from a population of over 600 healthy aged cats.
The impact of this work in defining healthy ageing is hoped to be two-fold. On the one hand providing, in a single resource, assessment criteria for use by veterinary practitioners seeking to provide the best care to their growing case load of ageing pet cats; on the other, providing a focal point for initiating future clinical research – for example, on the effects of specific interventions on ageing cats. There has been a paucity of research to date on feline ageing, but describing this project as ‘a long labour of love’, corresponding author, Dr Sally Perea, from Lewisburg, Ohio, USA, looks forward to a growing body of research and improved understanding in this area in future years.