Open AccessEffect of Feeding an Iodine‐Restricted Diet in Cats with Spontaneous Hyperthyroidism
Author(s) -
Hui T.Y.,
Bruyette D.S.,
Moore G.E.,
ScottMoncrieff J.C.
Publication year - 2015
Publication title -
journal of veterinary internal medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.356
H-Index - 103
eISSN - 1939-1676
pISSN - 0891-6640
DOI - 10.1111/jvim.13368
Subject(s) - cats , medicine , creatinine , reference range , iodine , blood urea nitrogen , endocrinology , urine specific gravity , body weight , zoology , renal function , urea , iodine deficiency , physiology , thyroid , urine , biology , biochemistry , chemistry , organic chemistry
Background Exclusive feeding of an iodine‐restricted diet has been proposed as a method for controlling clinical manifestations of hyperthyroidism in hyperthyroid cats. Objectives To determine the effect of feeding an iodine‐restricted diet on TT 4 concentrations and clinical signs in cats with spontaneous hyperthyroidism. Animals Forty‐nine client‐owned cats with spontaneous hyperthyroidism. Methods Retrospective case series. Hyperthyroid cats were exclusively fed a commercially available iodine‐restricted diet. Clinical response was assessed by change in weight and heart rate and serum TT 4, blood urea nitrogen (BUN), and creatinine concentrations at various times during dietary management (21–60 days, 60–180 days). Results Serum TT 4 normalized in 20/48 cats (42%) and 39/47 cats (83%) at 21–60 days and 61–180 days, respectively. Cats in which the TT 4 concentrations were still above reference range at 21–60 days had a significantly higher starting TT 4 than those that normalized their TT 4 levels during the same time period ( P = .038). Body weight did not significantly increase ( P = .34) nor heart rate decrease ( P = .64) during the study. There was a significant decrease in serum creatinine ( P = .028). Cats in the low reference range for serum TT 4 concentrations did not have a significant increase in body weight ( P = .41) nor creatinine ( P = .54) when compared to those with high reference range. Conclusions and Clinical Importance Restricted‐iodine diets were effective at maintaining serum TT 4 concentrations within reference ranges for a majority of cats with spontaneous hyperthyroidism over 1 year, although not all clinical signs of hyperthyroidism improved.