Survival times for cats with hyperthyroidism treated with iodine 131, methimazole, or both: 167 cases (1996–2003)

Milner, Rowan J.; Channell, Carla D.; Levy, Julie; Schaer, Michael

doi:10.2460/javma.228.4.559

Cited by 73 publications

(94 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…16, 17, 28 In other words, severe overt iatrogenic hypothyroidism is likely to both reduce GFR and increase serum creatinine concentrations to a greater extent than does subclinical hypothyroidism, in which serum T 4 concentrations remain within the lower end of the reference interval. The different resultant thyroid status after 131 I treatment in treated cats might explain the varied incidence of azotemia (15–49%) reported after treatment 7, 17, 29…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Efficacy of Low‐dose (2 millicurie) versus Standard‐dose (4 millicurie) Radioiodine Treatment for Cats with Mild‐to‐Moderate Hyperthyroidism

Lucy

Peterson

Randolph

et al. 2017

Veterinary Internal Medicne

127

View full text Add to dashboard Cite

BackgroundRadioiodine (131I) is effective treatment for hyperthyroidism in cats, but optimal dose to restore euthyroidism without inducing hypothyroidism is unclear. Treatment‐induced hypothyroidism can lead to azotemia and reduced duration of survival.ObjectiveTo compare efficacy and short‐term outcomes of low‐dose 131I versus higher, standard‐dose 131I as treatment for hyperthyroidism.AnimalsA total of 189 client‐owned cats undergoing 131I treatment for mild‐to‐moderate hyperthyroidism (serum T4 ≥ 4.0 μg/dL and <13.0 μg/dL).MethodsProspective, nonrandomized, cohort study comparing treatment with either low‐dose (2 mCi, n = 150) or standard‐dose (4 mCi, n = 39) 131I. Serum T4, thyroid‐stimulating hormone (TSH), and creatinine concentrations were measured after 1, 3, and 6 months to determine persistent hyperthyroidism, overt hypothyroidism (low T4, high TSH), subclinical hypothyroidism (normal T4, high TSH), and azotemia.ResultsThere was no significant difference in prevalence of cats with persistent hyperthyroidism between standard‐ and low‐dose treatment groups at 3 (0% versus 5.3%; P = .34) and 6 (0% versus 3.3%; P = .51) months. Overt (18% versus 1%; P = .0005) or subclinical (46% versus 21%; P = .004) hypothyroidism was more common in cats at 6 months after standard‐dose 131I. No difference in incidence of azotemia existed between groups, but cats treated with standard‐dose 131I had higher creatinine concentrations (P < .05) and higher percent rises in creatinine (P < .0001).Conclusions and Clinical ImportanceLow‐dose 131I is safe and effective for cats with mild‐to‐moderate hyperthyroidism, as evidenced by a cure rate of >95% with reduced frequency of iatrogenic hypothyroidism and azotemia.

show abstract

Section: Discussionmentioning

confidence: 99%

“…Treatment options include antithyroid drugs such as methimazole or carbimazole, iodine‐restricted diet, thyroidectomy, or radioactive iodine 3, 4, 5, 6. Radioiodine ( 131 I) is generally considered the optimal treatment for hyperthyroidism in cats because of its safety and efficacy 1, 5, 7, 8…”

mentioning

confidence: 99%

Efficacy of Low‐dose (2 millicurie) versus Standard‐dose (4 millicurie) Radioiodine Treatment for Cats with Mild‐to‐Moderate Hyperthyroidism

Lucy

Peterson

Randolph

et al. 2017

Veterinary Internal Medicne

127

View full text Add to dashboard Cite

show abstract

“…No sex or breed of animals predisposition exists for development of the disease (Milner et al 2006). A progressive, mild to severe weight loss coupled with normal to increased appetite, is consistent with feline hyperthyroidism (Peterson et al, 1983;Broussard et al, 1995).…”

Section: Historymentioning

confidence: 99%

“…Azotaemia is present in about 10% of the cases; an expected finding since chronic kidney disease is also common in elderly cats (Broussard et al, 1995;Plantiga et al, 2005). Less commonly, potassium coagulation parametres, serum folate and cobalamin may be affected (Randolph et al, 2006;Milner et al, 2006;Cook et al, 2011).…”

Section: Cardiovascular Manifestationsmentioning

confidence: 99%

Feline hyperthyroidism: diagnosis and treatment

Kasabalis

Soubasis

Petanides

2017

J Hellenic Vet Med Soc

View full text Add to dashboard Cite

Hyperthyroidism is a common endocrinopathy in cats older than 8 years, with no sex or breed predisposition. Benign adenomas and adenomatous hyperplasia of the thyroid gland is observed in the majority of cases. Symptoms reflect the effect of thyroid hormone excess in various systems, with weight loss, polyphagia, polyuria-polydipsia, cardiovascular and gastrointestinal abnormalities being common clinical manifestations. On clinical examination, there is frequently prominent thyroid enlargement. Common laboratory abnormal findings include increased activity of alkaline phosphatase and alanino-aminotransferase, hyperphosphataemia, azotaemia and decreased concentration of ionized calcium and creatinine. Definite diagnosis of the disease is based on the demonstration of increased blood concentration of thyroid hormones.Measurement of thyroxine concentration, alone or in conjunction with concentration of free thyroxine, is usually sufficient to reach a diagnosis. When diagnosis is uncertain, thyroid stimulating hormone, scintigraphy and dynamic function tests can be used. The possibility of concurrent diseases (e.g., renal failure, diabetes mellitus) must be investigated, as their presence has implications on diagnosis and treatment. Medical therapy, thyroidectomy, radionine therapy and low iodine diet are also valid options for treatment. Each has advantages and disadvantages that a clinician must take into consideration before instigating treatment. Prognosis for hyperthyroidism is favourable if no severe disease exists concurrently.

show abstract

“…3 Radioiodine is regarded as the gold standard treatment, with advantages including: (i) potential for curative treatment, with approximately 94% of cats cured following a single treatment, 4 (ii) efficacy independent of location and type of hyperfunctional thyroid tissue, (iii) longer median survival compared to cats treated with anti-thyroid drugs, (iv) superior cost effectiveness for cats surviving beyond one year following diagnosis compared with anti-thyroid drugs and (v) safety, with minimal adverse effects and no requirement for general anaesthesia or even sedation in most instances. [4][5][6][7][8] However, restricted accessibility and requirement for hospitalisation can represent potential barriers to radioiodine use. 7,9 Curative success of thyroidectomy is dependent on the location of hyperfunctional thyroid tissue, which is important as ectopic hyperfunctional thyroid has been reported in 4 to 23% of hyperthyroid cats.…”

Section: Introductionmentioning

confidence: 99%

Management and monitoring of hyperthyroid cats: a survey of Australian veterinarians

Kopecny¹,

Higgs

Hibbert

et al. 2016

Journal of Feline Medicine and Surgery

View full text Add to dashboard Cite

General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/pure/about/ebr-terms Method:An invitation to complete an online survey was sent to veterinarians in all states and territories of Australia. The survey comprised questions relating to management of hyperthyroidism, use of anti-thyroid drugs v radioiodine treatment v surgical thyroidectomy, in addition to demographic information for respondents. Results:A total of 546 clinicians completed the survey. The most commonly preferred treatments for long-term management of feline hyperthyroidism were anti-thyroid medications (305/546; 56%) and radioiodine (210/546; 38%), with substantially more respondents selecting radioiodine when cost was removed as a consideration (425/546; 78%). However, most respondents had treated or referred few cases for radioiodine (median 2). Most veterinarians (500/546; 92%) used anti-thyroid medications either long-term or prior to definitive treatment of hyperthyroidism. For medical management, 45% (244/546) of veterinarians used twice daily carbimazole. Half of respondents (274/546) aimed to 3 maintain the total T4 concentration anywhere within the laboratory reference interval (RI) in hyperthyroid cats without chronic kidney disease. Blood pressure monitoring was uncommon. Surgical thyroidectomy was rarely performed. Conclusions:Radioiodine was more frequently preferred by Australian veterinarians compared to those in the UK, likely associated with greater availability, reduced cost and shorter hospitalisation times in this jurisdiction, though anti-thyroid medications were the most frequently used treatment modality. Barriers remain to its utilisation, however, including perceived cost, misconceptions with regard to expected success rate and accessibility. Recent changes to recommendations on the management and monitoring of hyperthyroid cats do not appear to have been widely adopted by veterinarians at this time.

show abstract

Survival times for cats with hyperthyroidism treated with iodine 131, methimazole, or both: 167 cases (1996–2003)

Abstract: Results suggest that age, preexisting renal disease, and treatment type were associated with survival time in cats undergoing medical treatment of hyperthyroidism.

Cited by 73 publications

References 18 publications

Efficacy of Low‐dose (2 millicurie) versus Standard‐dose (4 millicurie) Radioiodine Treatment for Cats with Mild‐to‐Moderate Hyperthyroidism

Efficacy of Low‐dose (2 millicurie) versus Standard‐dose (4 millicurie) Radioiodine Treatment for Cats with Mild‐to‐Moderate Hyperthyroidism

Feline hyperthyroidism: diagnosis and treatment

Management and monitoring of hyperthyroid cats: a survey of Australian veterinarians

Contact Info

Product

Resources

About