Prevalence and breed predisposition for thoracolumbar intervertebral disc disease in cats

Objectives The objective was to evaluate the prevalence and possible breed predilections for thoracolumbar intervertebral disc disease (IVDD) in cats. Methods Medical records and imaging studies of cats diagnosed with thoracolumbar IVDD between January 2008 and August 2014 were retrospectively reviewed and compared with the general hospital population. The association between type of IVDD (ie, intervertebral disc extrusion [IVDE] or intervertebral disc protrusion [IVDP]) and breed, age, sex, and duration and severity of clinical signs was also evaluated. Results Of 12,900 cats presented during the study period, 31 (0.24%) were diagnosed with IVDD, including 17 purebred and 14 non-purebred cats. Of all presented purebred cats, 0.52% were diagnosed with thoracolumbar IVDD. More specifically, 1.29% of all British Shorthairs and 1.83% of all presented Persians were diagnosed with IVDD. Compared with the general hospital population, purebred cats ( P = 0.0001), British Shorthairs ( P <0.0001) and Persians ( P = 0.0006) were significantly overrepresented with thoracolumbar IVDD. Affected purebred cats were younger than affected non-purebred cats ( P = 0.02). Of 31 cats with IVDD, 19 were diagnosed with IVDE and 12 with IVDP. Cats with IVDE had a significantly shorter duration of clinical signs ( P = 0.0002) and demonstrated more severe neurological deficits ( P = 0.04) than cats with IVDP. Conclusions and relevance Although thoracolumbar IVDD is an uncommon condition in cats, purebred cats, British Shorthairs and Persians, were overrepresented. It is currently unclear if this represents a true breed predisposition or a higher likelihood of owners of purebred cats seeking referral for advanced diagnostic imaging procedures.