Etiologic classification of seizures, signalment, clinical signs, and outcome in cats with seizure disorders: 91 cases (2000-2004).

To evaluate associations among etiologic classifications of seizures and signalment, clinical signs, and outcome in cats with various seizure disorders. Retrospective case series. 91 cats evaluated for seizure disorders at a veterinary teaching hospital from 2000 through 2004. Data regarding characteristics of the cats and their seizures were obtained from medical records. Seizures were classified as reactive, symptomatic, or idiopathic. Survival times were displayed as Kaplan-Meier curves, and differences between etiologic classifications were assessed by log-rank test. Over the 5-year period, the incidence of seizures among all cats evaluated at the hospital was 2.1%. Etiology was classified as reactive in 20 (22%) cats, symptomatic in 45 (50%), idiopathic or presumptive idiopathic in 23 (25%), and cardiac syncope in 3 (3%). Focal seizures with or without secondary generalization were recorded for 47 (52%) cats, and primary generalized seizures with or without status epilepticus were recorded for 44 (48%). Etiology was not associated with seizure type. However, mean age of cats with idiopathic seizures (3.5 years) was significantly lower than that of cats with reactive seizures (8.2 years) or symptomatic seizures (8.1 years). The 1-year survival rate for cats with idiopathic seizures (0.82) was longer than that for cats with reactive (0.50) or symptomatic (0.16) seizures. Seizure etiology was symptomatic or reactive in most cats. Underlying disease was not associated with seizure type. Cats with idiopathic seizures lived longer than did cats with reactive or symptomatic seizures but were also younger.