Prevalence of Disease and Age-Related Behavioural Changes in Cats: Past and Present.

(1) Background: age-related changes in behaviour and health may be thought of as "normal" ageing; however, they can reflect under-diagnosed, potentially treatable, conditions. This paper describes the prevalence of age-related behavioural changes and disease in two UK cat populations at separate time-points. (2) Methods: owners of cats aged ≥11 years completed questionnaires in 1995 (cohort 1: = 1236), and from 2010-2015 (cohort 2: = 883). (3) Results: the most important behavioural changes in these cats were increased affection towards their owners (reported by 51.9% in 1995; 35.8% in 2010-2015), increased vocalisation (63.5%; 58.9%, respectively), particularly at night (32%; 43.6%), and house-soiling (29.3%; 55.8%). Most (79.4%; 81%) of the cats had visited a veterinary surgeon since becoming 11 years old. The main reasons, aside from vaccinations, were dental disease, renal disease and lower urinary tract disorders in 1995, and dental disease, renal disease and hyperthyroidism in 2010-2015. All major diagnoses were reported significantly more frequently in 2010-2015 than in 1995; behavioural changes were variably associated with these diseases. (4) Conclusion: elderly cats display age-related behavioural changes and develop diseases that may be under-diagnosed. Veterinarians need to ask owners about these behavioural changes, as they may signify manageable conditions rather than reflect "normal" ageing.