Risk factors for low plasma thyroxine and high plasma thyroid-stimulating hormone concentrations in dogs with non-thyroidal diseases

Abstract

The aim of the current study was to identify independent risk factors for thyroid axis alterations in dogs with non-thyroidal diseases. In this retrospective cross-sectional study, data and plasma samples from 207 dogs with non-thyroidal diseases was used. The involvement of various factors (disease severity, sex, age, breed, category and duration of disease, and medication) in the alteration of plasma thyroxine (T4) or thyroid-stimulation hormone (TSH) concentrations was analyzed using multivariate logistic regression. Among the 207 dogs analyzed, 99 (47.8%) had low plasma T4 concentrations, while 45 (21.7%) had high TSH concentrations. Intact male sex [odds ratio (OR), 3.25; 1.67–6.35; P <0.001], Labrador Retrievers (OR, 18.70; 2.32–151.00; P =0.006), moderate (OR, 2.39; 1.21–4.74; P =0.012) and severe diseases (OR, 6.84; 2.27–20.70; P <0.001) were associated with increased risk for low plasma T4 concentrations. Meanwhile, intact male (OR, 3.93; 1.51–10.30; P =0.005), spayed female (OR, 4.22; 1.59–11.20; P =0.004), older age (OR, 2.73; 1.28–5.84; P =0.009), and Miniature Dachshunds (OR, 5.39; 2.38–12.20; P <0.001) had increased risk for high plasma TSH concentrations. Disease severity had been determined as an independent risk factor for canine NTIS. In addition, sex, age and breed were also associated with thyroid axis alterations in dogs with non-thyroidal diseases.

Serum thyroxine and thyrotropin concentrations decrease with severity of nonthyroidal illness in cats and predict 30‐day survival outcome

“…[1][2][3]7,8 Similarly, several nonthyroidal illnesses suppress serum T 4 and T 3 to low concentrations in dogs. [9][10][11][12] In both humans and dogs, serum fT 4 concentrations, when measured by equilibrium dialysis, usually remain within the reference interval. [1][2][3]8 Most human patients with NTIS initially have normal serum TSH concentrations, but many will develop low TSH concentrations, especially those with severe illness.…”

“…9,10,17 In both human and dogs with NTIS, the finding of low serum T 4 or fT 4 concentrations, together with high TSH concentrations, complicates evaluation of thyroid function and increases the risk for misdiagnosis of primary hypothyroidism. [1][2][3]11,18 In both humans 3,[19][20][21][22][23] and dogs 10,12 with NTIS, development of low serum T 4 and T 3 concentrations increases the likelihood of death, a finding that might be useful as a prognostic indicator. Furthermore, in both humans and dogs, finding of low serum TSH concentrations has predicted mortality.…”

“…35,36 If cats with NTIS do occasionally develop high serum TSH concentrations, this finding could lead to an erroneous diagnosis of hypothyroidism, as reported in humans and dogs with NTIS. [1][2][3]11,18 We sought to better determine the effect of nonthyroidal illness on commonly used serum pituitary-thyroid function tests (T 4 , T 3 , fT 4 , TSH) in cats. Furthermore, we sought to determine the effect of severity of illness and disease category on serum thyroid hormone and TSH concentrations, as well as to examine whether abnormalities in any of these hormones could predict patient outcome and survival.…”

Improvement Effect of 5-Aminolevulinic Acid on Hyperlipidemia in Miniature Schnauzer Dogs: An Open Study in 5 Cases of One Pedigree

“…Case 1 had low FT4 levels, and cases 1 and 4 showed normal T4 but high TSH concentrations, indicating potential hypothyroidism or occasional thyroid axis alteration. 23 Pancreatitis might also be associated with hypertriglyceridemia in case 1, 3 because of the elevated lipase activity. The bodyweight of all cases decreased with 5-ALA treatment, and the mean (± SE) bodyweight (kg) was significantly lower after 3 (8.38 ± 0.17), 6 (7.82 ± 0.16), and 7 (7.38 ± 0.17) months, compared with that prior to treatment (9.04 ± 0.21, P < 0.01).…”

Recombinant human thyrotropin stimulation test in 114 dogs with suspected hypothyroidism: a cross‐sectional study

“…2019, Nishii et al . 2019). Furthermore, age‐ and breed‐specific reference intervals should be used when interpreting T4 concentration (Gonzalez & Kaleem Quadri 1988, Reimers et al .…”