Biological Variability in Serum Cortisol Concentration Post-adrenocorticotropic Hormone Stimulation in Healthy Dogs

A. Gal, K. Weidgraaf, J. P. Bowden, N. Lopez-Villalobos, N. J. Cave, J. P. Chambers, F. Castillo-Alcala

Research output: Contribution to journalArticle

Abstract

Background: The ACTH stimulation has low sensitivity for the diagnosis of hypercortisolism possibly as a result of biological and analytical variability. Hypothesis/Objectives: To report the components of biological and analytical variability in serum cortisol concentration post-ACTH stimulation ([cortisol]) in healthy dogs. Animals: Fourteen healthy harrier hound dogs. Methods: The data were extracted from a separate, prospective, randomized, double-blinded, controlled discovery study in which dogs treated with vehicle control and 4 different doses of cortisone acetate (CA) for 7 days had an ACTH stimulation test performed to confirm the dose-dependent effect of CA. The index of individuality (IoI), the critical difference between sequential measurements (CD), and the number of measurements required to assess the homeostatic set point (HSP) of [cortisol] with confidence intervals (CI) of 90 and 95% were estimated. Results: The IoI was equal to 1.1 and the CD was 3.3 μg/dL (92 nmol/L). The number of measurements required to assess the HSP of [cortisol] with CI of 90 and 95% were 3 and 15, respectively. Additionally, mean [cortisol] was higher in males than in females (13.3 ± 4 μg/dL [366 ± 114 nmol/L] vs. 11.5 ± 2.5 μg/dL [318 ± 65 nmol/L], respectively; P =.046). As expected, treatment with CA resulted in a dose-dependent suppression of [cortisol]. Conclusions and Clinical Importance: False-negative test results in hypercortisolism could occur when [cortisol] is outside of the individual's HSP and within the reference interval. The large CD emphasizes the importance of assessing clinically relevant parameters in the diagnosis and monitoring of HC.

Original languageEnglish (US)
Pages (from-to)711-716
Number of pages6
JournalJournal of veterinary internal medicine
Volume31
Issue number3
DOIs
StatePublished - May 1 2017
Externally publishedYes

Fingerprint

corticotropin
Adrenocorticotropic Hormone
cortisol
Hydrocortisone
Dogs
cortisone
dogs
Serum
Cushing syndrome
Cushing Syndrome
acetates
Individuality
confidence interval
dosage
Confidence Intervals
hounds
testing
monitoring
cortisone acetate
animals

Keywords

  • ACTH stimulation test
  • Canine
  • Cortisol
  • Critical difference
  • Index of individuality

ASJC Scopus subject areas

  • veterinary(all)

Cite this

Gal, A., Weidgraaf, K., Bowden, J. P., Lopez-Villalobos, N., Cave, N. J., Chambers, J. P., & Castillo-Alcala, F. (2017). Biological Variability in Serum Cortisol Concentration Post-adrenocorticotropic Hormone Stimulation in Healthy Dogs. Journal of veterinary internal medicine, 31(3), 711-716. https://doi.org/10.1111/jvim.14710

Biological Variability in Serum Cortisol Concentration Post-adrenocorticotropic Hormone Stimulation in Healthy Dogs. / Gal, A.; Weidgraaf, K.; Bowden, J. P.; Lopez-Villalobos, N.; Cave, N. J.; Chambers, J. P.; Castillo-Alcala, F.

In: Journal of veterinary internal medicine, Vol. 31, No. 3, 01.05.2017, p. 711-716.

Research output: Contribution to journalArticle

Gal, A, Weidgraaf, K, Bowden, JP, Lopez-Villalobos, N, Cave, NJ, Chambers, JP & Castillo-Alcala, F 2017, 'Biological Variability in Serum Cortisol Concentration Post-adrenocorticotropic Hormone Stimulation in Healthy Dogs', Journal of veterinary internal medicine, vol. 31, no. 3, pp. 711-716. https://doi.org/10.1111/jvim.14710
Gal, A. ; Weidgraaf, K. ; Bowden, J. P. ; Lopez-Villalobos, N. ; Cave, N. J. ; Chambers, J. P. ; Castillo-Alcala, F. / Biological Variability in Serum Cortisol Concentration Post-adrenocorticotropic Hormone Stimulation in Healthy Dogs. In: Journal of veterinary internal medicine. 2017 ; Vol. 31, No. 3. pp. 711-716.
@article{b6a3cb2585b44cd78a6b9326b402d85a,
title = "Biological Variability in Serum Cortisol Concentration Post-adrenocorticotropic Hormone Stimulation in Healthy Dogs",
abstract = "Background: The ACTH stimulation has low sensitivity for the diagnosis of hypercortisolism possibly as a result of biological and analytical variability. Hypothesis/Objectives: To report the components of biological and analytical variability in serum cortisol concentration post-ACTH stimulation ([cortisol]) in healthy dogs. Animals: Fourteen healthy harrier hound dogs. Methods: The data were extracted from a separate, prospective, randomized, double-blinded, controlled discovery study in which dogs treated with vehicle control and 4 different doses of cortisone acetate (CA) for 7 days had an ACTH stimulation test performed to confirm the dose-dependent effect of CA. The index of individuality (IoI), the critical difference between sequential measurements (CD), and the number of measurements required to assess the homeostatic set point (HSP) of [cortisol] with confidence intervals (CI) of 90 and 95{\%} were estimated. Results: The IoI was equal to 1.1 and the CD was 3.3 μg/dL (92 nmol/L). The number of measurements required to assess the HSP of [cortisol] with CI of 90 and 95{\%} were 3 and 15, respectively. Additionally, mean [cortisol] was higher in males than in females (13.3 ± 4 μg/dL [366 ± 114 nmol/L] vs. 11.5 ± 2.5 μg/dL [318 ± 65 nmol/L], respectively; P =.046). As expected, treatment with CA resulted in a dose-dependent suppression of [cortisol]. Conclusions and Clinical Importance: False-negative test results in hypercortisolism could occur when [cortisol] is outside of the individual's HSP and within the reference interval. The large CD emphasizes the importance of assessing clinically relevant parameters in the diagnosis and monitoring of HC.",
keywords = "ACTH stimulation test, Canine, Cortisol, Critical difference, Index of individuality",
author = "A. Gal and K. Weidgraaf and Bowden, {J. P.} and N. Lopez-Villalobos and Cave, {N. J.} and Chambers, {J. P.} and F. Castillo-Alcala",
year = "2017",
month = "5",
day = "1",
doi = "10.1111/jvim.14710",
language = "English (US)",
volume = "31",
pages = "711--716",
journal = "Journal of Veterinary Internal Medicine",
issn = "0891-6640",
publisher = "Wiley-Blackwell",
number = "3",

}

TY - JOUR

T1 - Biological Variability in Serum Cortisol Concentration Post-adrenocorticotropic Hormone Stimulation in Healthy Dogs

AU - Gal, A.

AU - Weidgraaf, K.

AU - Bowden, J. P.

AU - Lopez-Villalobos, N.

AU - Cave, N. J.

AU - Chambers, J. P.

AU - Castillo-Alcala, F.

PY - 2017/5/1

Y1 - 2017/5/1

N2 - Background: The ACTH stimulation has low sensitivity for the diagnosis of hypercortisolism possibly as a result of biological and analytical variability. Hypothesis/Objectives: To report the components of biological and analytical variability in serum cortisol concentration post-ACTH stimulation ([cortisol]) in healthy dogs. Animals: Fourteen healthy harrier hound dogs. Methods: The data were extracted from a separate, prospective, randomized, double-blinded, controlled discovery study in which dogs treated with vehicle control and 4 different doses of cortisone acetate (CA) for 7 days had an ACTH stimulation test performed to confirm the dose-dependent effect of CA. The index of individuality (IoI), the critical difference between sequential measurements (CD), and the number of measurements required to assess the homeostatic set point (HSP) of [cortisol] with confidence intervals (CI) of 90 and 95% were estimated. Results: The IoI was equal to 1.1 and the CD was 3.3 μg/dL (92 nmol/L). The number of measurements required to assess the HSP of [cortisol] with CI of 90 and 95% were 3 and 15, respectively. Additionally, mean [cortisol] was higher in males than in females (13.3 ± 4 μg/dL [366 ± 114 nmol/L] vs. 11.5 ± 2.5 μg/dL [318 ± 65 nmol/L], respectively; P =.046). As expected, treatment with CA resulted in a dose-dependent suppression of [cortisol]. Conclusions and Clinical Importance: False-negative test results in hypercortisolism could occur when [cortisol] is outside of the individual's HSP and within the reference interval. The large CD emphasizes the importance of assessing clinically relevant parameters in the diagnosis and monitoring of HC.

AB - Background: The ACTH stimulation has low sensitivity for the diagnosis of hypercortisolism possibly as a result of biological and analytical variability. Hypothesis/Objectives: To report the components of biological and analytical variability in serum cortisol concentration post-ACTH stimulation ([cortisol]) in healthy dogs. Animals: Fourteen healthy harrier hound dogs. Methods: The data were extracted from a separate, prospective, randomized, double-blinded, controlled discovery study in which dogs treated with vehicle control and 4 different doses of cortisone acetate (CA) for 7 days had an ACTH stimulation test performed to confirm the dose-dependent effect of CA. The index of individuality (IoI), the critical difference between sequential measurements (CD), and the number of measurements required to assess the homeostatic set point (HSP) of [cortisol] with confidence intervals (CI) of 90 and 95% were estimated. Results: The IoI was equal to 1.1 and the CD was 3.3 μg/dL (92 nmol/L). The number of measurements required to assess the HSP of [cortisol] with CI of 90 and 95% were 3 and 15, respectively. Additionally, mean [cortisol] was higher in males than in females (13.3 ± 4 μg/dL [366 ± 114 nmol/L] vs. 11.5 ± 2.5 μg/dL [318 ± 65 nmol/L], respectively; P =.046). As expected, treatment with CA resulted in a dose-dependent suppression of [cortisol]. Conclusions and Clinical Importance: False-negative test results in hypercortisolism could occur when [cortisol] is outside of the individual's HSP and within the reference interval. The large CD emphasizes the importance of assessing clinically relevant parameters in the diagnosis and monitoring of HC.

KW - ACTH stimulation test

KW - Canine

KW - Cortisol

KW - Critical difference

KW - Index of individuality

UR - http://www.scopus.com/inward/record.url?scp=85017552587&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85017552587&partnerID=8YFLogxK

U2 - 10.1111/jvim.14710

DO - 10.1111/jvim.14710

M3 - Article

C2 - 28407311

AN - SCOPUS:85017552587

VL - 31

SP - 711

EP - 716

JO - Journal of Veterinary Internal Medicine

JF - Journal of Veterinary Internal Medicine

SN - 0891-6640

IS - 3

ER -