Just Ask the Expert: What is the lifespan of cats with hyperthyroidism?
Dr. Bruyette welcomes endocrinology questions from veterinarians and veterinary technicians.
Are there any studies, perhaps evaluating age and T4 or creatinine concentrations, that provide statistical comparisons of the lifespan of hyperthyroid cats with and without treatment?
Thomas McCoy, DVM
No data that I can find prospectively examines the lifespan of untreated hyperthyroid cats compared with the nonhyperthyroid cat population or attempts to compare the survival of untreated hyperthyroid cats with those that undergo treatment. Such studies would be hard to conduct given the safety and efficacy of the various treatment options, the recognized morbidity and mortality that can result from untreated or poorly controlled hyperthyroidism, and the ease of diagnosis and monitoring.
Ultimately, the decision to treat or not treat a cat with hyperthyroidism is left to the veterinarian and pet owner, who make an informed decision by taking into account multiple variables (e.g. age, concurrent illness and medications, severity of clinical signs, suitability or availability of various treatment options) and then deciding which course of action is in the patient's best interest.
David S. Bruyette, DVM, DACVIM
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