Periodontal disease is one of the most common conditions diagnosed in cats, affecting 13.9 percent of those presented to primary-care practices (O’Neill et al., 2014).
What do we currently know?
Gingivitis is inflammation of the gingiva. It is characterised by reddening and oedema of the tissue, which later progresses to visible ulceration with spontaneous bleeding (Reiter, 2018). It is the first and only reversible stage of periodontal disease and always precedes periodontitis, which affects the non-gingival components of the periodontium (the periodontal ligament, cementum and alveolar bone). Therefore, early detection and management of gingivitis is vital for preventing disease progression (Bellows et al., 2019).
Previously identified risk factors for gingivitis include breed and diet; however, this evidence is often limited
Previous research suggests the prevalence estimates of gingivitis in cats range from 8 to 73.2 percent (Vapalahti et al., 2016; Verhaert and Van Wetter, 2004). Previously identified risk factors for gingivitis include breed and diet; however, this evidence is often limited. Furthermore, previous research on feline gingivitis has primarily been carried out on cats living in a research environment, which may not be generalisable to companion cats (Williams et al., 2024).
What did the latest study do?
A new study by Jess Williams and colleagues at the University of Bristol, published in the Journal of Small Animal Practice, is the first to use prospectively collected data to estimate the prevalence of and risk factors for gingivitis in a cohort of domestic cats (Williams et al., 2024).
The researchers used data from a longitudinal study of 860 domestic cats that were aged up to six years and enrolled in the Bristol Cats Study. Data was derived from owner-completed questionnaires and veterinary surgeon-completed oral health (OH) scores. Veterinary surgeons identified a grade of severity for the periodontal disease using an oral health scorecard with a five-point scale. Gingivitis was defined as an OH grade of one or above.
Prevalence estimates for cats up to six years old were determined for different age groups. Potential risk factors, including cat signalment, diet and dental care, were assessed for association with gingivitis in cats aged three to four years. This is because enough cats were expected to have developed signs of gingivitis by this age, and a sufficient number of cats within the study cohort would have reached this age to provide sufficient statistical power.
What were the findings?
Gingivitis was a common condition in cats aged up to six years. Prevalence increased with age, from 24.5 percent in cats less than 12 months old and up to 56.3 percent in cats between five and six years old.
Odds of gingivitis in cats aged three to four years were higher in:
- Cats fed a wet-only or mixed wet/dry diet compared to those on a dry-only diet
- Cats not reported to hunt prey compared to reported hunters
- Cats reported to dribble while being stroked at the age of six months compared to reported non-dribblers
- Cats with orange variants in their coat colour compared to non-orange cats.
Sex was not found to be a risk factor for gingivitis, and the effect of neuter status could not be assessed as very few of the cats in the cohort were entire.
How does this compare to previous studies?
The finding that the odds of gingivitis were decreased if cats were fed only a dry diet is consistent with those found in previous studies (Buckley et al., 2011). Although diet recommendations can be given to owners by veterinary professionals, gingivitis shouldn’t be the sole consideration for dietary decisions as dry-only diets have been associated with an increased obesity risk and lower urinary tract disease (Williams et al., 2024).
Reasons for the association between dribbling when stroked at six months of age and the higher odds of gingivitis are unclear. This is also the first time that increased odds of gingivitis in cats with orange variants in their coat colour has been confirmed, although it has been anecdotally reported before. It could be that the X-linked O-locus responsible for orange coat colour variants in cats is linked to a predisposition to gingivitis, but this requires further research (Williams et al., 2024).
This is also the first time that increased odds of gingivitis in cats with orange variants in their coat colour has been confirmed, although it has been anecdotally reported before
The difference between the prevalence estimates in this study (24.5 to 56.3 percent) and those found in previous studies (8 percent by Vapalahti et al. (2016) and 73.2 percent by Verhaert and Van Wetter (2004)) may be due to different methods of diagnosis and reporting between the different studies. In particular, the study by Williams et al. only used data from conscious examinations, which may underestimate the true prevalence of gingivitis. The difference in age between studies may also impact prevalence estimates.
Limitations of the evidence
Limitations of the study were that:
- It only included cats that attended a veterinary practice and had an OH card completed by their veterinary surgeon
- There may have been variations between different veterinary surgeons in the OH assessment and scoring criteria
- There may have been a possible bias towards highly motivated cat owners who are more likely to complete annual health questionnaires
Take-home messages
Overall, this study confirms that the prevalence of gingivitis in cats increases with age. It also suggests that the odds of gingivitis in cats aged three to four years is higher in cats fed a wet-only or mixed wet/dry diet, as well as in cats not reported to hunt prey, cats reported to dribble while being stroked at the age of six months and cats with orange coats.
These findings can help veterinary surgeons identify cats at greater risk of gingivitis and advise owners on dietary and oral healthcare recommendations to protect against gingivitis
These findings can help veterinary surgeons identify cats at greater risk of gingivitis and advise owners on dietary and oral healthcare recommendations to protect against gingivitis. As even young cats may have signs of gingivitis, it is important to discuss and monitor dental health regularly and early on in a cat’s life, especially for those cats who may be more at risk.
