Peer-reviewed veterinary case report
Body weight and muscle loss in cats with hyperthyroidism
By Peterson, M E et al.·Published in Journal of veterinary internal medicine·2016·Animal Endocrine Clinic, United States·View original on PubMed →
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Original publication title: Evaluation of Body Weight, Body Condition, and Muscle Condition in Cats with Hyperthyroidism.
- Species:
- cat
Plain-English summary
A group of 462 cats with hyperthyroidism (a condition that causes weight loss) were evaluated for body weight and muscle condition. Many of these cats were found to be thin or had lost muscle mass. After treatment, most cats gained weight and improved their body condition, but about 45% still showed some muscle wasting. This means that while treatment can help cats regain weight, some may not fully recover their muscle strength.
People also search for: cat hyperthyroidism symptoms · cat weight loss treatment · cat muscle wasting after hyperthyroidism
Abstract
BACKGROUND: The contribution of fat loss versus muscle wasting to the loss of body weight seen in hyperthyroid cats is unknown. OBJECTIVES: To investigate body weight, body condition score (BCS), and muscle condition score (MCS) in hyperthyroid cats. ANIMALS: Four hundred sixty-two cats with untreated hyperthyroidism, 117 of which were reevaluated after treatment. METHODS: Prospective cross-sectional and before-after studies. Untreated hyperthyroid cats had body composition evaluated (body weight, BCS, and MCS). A subset of these cats were reevaluated 3-12 months after treatment when euthyroid. RESULTS: Pretreatment body weight (median, 4.36 kg; IQR, 3.5 to 5.2 kg) was lower than premorbid weight (5.45 kg; IQR, 4.6 to 6.4 kg, P < .0001) recorded 1-2 years before diagnosis. 154 (35.3%) cats were thin or emaciated; 357 (77.3%) had loss of muscle mass. Cats showed increases in body weight (median, 4.1 kg to 5.0 kg), BCS (median, 3/5 to 3.5/5), and MCS (2/3 to 3/3) after treatment (P < .001), but mild-to-moderate muscle wasting persisted in 45% of treated cats. CONCLUSIONS AND CLINICAL IMPORTANCE: Most hyperthyroid cats lose body weight but maintain an ideal or overweight BCS, with only a third being underweight. As in human hyperthyroid patients, this weight loss is associated with muscle wasting, which affects >75% of hyperthyroid cats. Successful treatment leads to weight gain and increase of BCS in most cats, but almost half fail to regain normal muscle mass.
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Search related cases →Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/27667652/