The development of decision limits for the implementation of the GH-2000 detection methodology using current commercial insulin-like growth factor-I and amino-terminal pro-peptide of type III collagen assays

TY - JOUR

T1 - The development of decision limits for the implementation of the GH-2000 detection methodology using current commercial insulin-like growth factor-I and amino-terminal pro-peptide of type III collagen assays

AU - Erotokritou-Mulligan, Ioulietta

AU - Guha, Nishan

AU - Stow, Michael

AU - Bassett, E. Eryl

AU - Bartlett, Christiaan

AU - Cowan, David A.

AU - Soenksen, Peter H.

AU - Holt, Richard I. G.

PY - 2012/4

Y1 - 2012/4

N2 - Background: The GH-2000 project developed a method for detecting GH misuse based on the measurement of insulin-like growth factor-I (IGF-I) and the amino-terminal pro-peptide of type III collagen (P-III-NP). The objective of this study was to develop decision limits for the GH-2000 score to detect GH misuse in elite athletes using two currently available commercial assays for each analyte. Study design: Subjects: 404 male (mean age 23.9 yrs, range 12-37 yrs) and 94 female elite athletes (mean age 24.5 yrs, range 18-34 yrs) participated. Blood samples were collected according to World Anti-Doping Agency (WADA) guidelines at various sporting events including 238 samples collected as part of the UK Anti-Doping Testing Programme. Laboratory analysis: IGF-I was measured by Siemens Immulite IGF-I assay and Immunotech A15729 IGF-I IRMA. P-III-NP was measured by RIA-gnost P-III-P and the UniQ (TM) PIIINP RIA. Statistical analysis: The GH-2000 score decision limits were developed through the analysis of the elite athlete samples. Results: For males and females separately, the distributions of GH-2000 scores were consistent with Normal distributions. Using a specificity of 99.99% new decision limits were determined which included an allowance for uncertainty associated with calculations based on a finite sample size. One outlier was identified with results incompatible with normal physiology and tested positive with the current isoform GH test. Conclusions: We have developed decision limits using currently available commercial assays to measure IGF-I and P-III-NP in elite athletes. This should allow the introduction of a test for CH misuse based on the measurement of these GH sensitive biomarkers.

AB - Background: The GH-2000 project developed a method for detecting GH misuse based on the measurement of insulin-like growth factor-I (IGF-I) and the amino-terminal pro-peptide of type III collagen (P-III-NP). The objective of this study was to develop decision limits for the GH-2000 score to detect GH misuse in elite athletes using two currently available commercial assays for each analyte. Study design: Subjects: 404 male (mean age 23.9 yrs, range 12-37 yrs) and 94 female elite athletes (mean age 24.5 yrs, range 18-34 yrs) participated. Blood samples were collected according to World Anti-Doping Agency (WADA) guidelines at various sporting events including 238 samples collected as part of the UK Anti-Doping Testing Programme. Laboratory analysis: IGF-I was measured by Siemens Immulite IGF-I assay and Immunotech A15729 IGF-I IRMA. P-III-NP was measured by RIA-gnost P-III-P and the UniQ (TM) PIIINP RIA. Statistical analysis: The GH-2000 score decision limits were developed through the analysis of the elite athlete samples. Results: For males and females separately, the distributions of GH-2000 scores were consistent with Normal distributions. Using a specificity of 99.99% new decision limits were determined which included an allowance for uncertainty associated with calculations based on a finite sample size. One outlier was identified with results incompatible with normal physiology and tested positive with the current isoform GH test. Conclusions: We have developed decision limits using currently available commercial assays to measure IGF-I and P-III-NP in elite athletes. This should allow the introduction of a test for CH misuse based on the measurement of these GH sensitive biomarkers.

KW - Growth hormone

KW - Doping

KW - Test

KW - Insulin-like growth factor-I (IGF-I)

KW - Amino-terminal pro-peptide of type III collagen (P-III-NP)

KW - HORMONE ABUSE

KW - GH ABUSE

KW - IGF-I

KW - PROCOLLAGEN

KW - SPORT

KW - PROPEPTIDE

KW - MARKERS

U2 - 10.1016/j.ghir.2011.12.005

DO - 10.1016/j.ghir.2011.12.005

M3 - Article

SN - 1096-6374

VL - 22

SP - 53

EP - 58

JO - GROWTH HORMONE AND IGF RESEARCH

JF - GROWTH HORMONE AND IGF RESEARCH

IS - 2

M1 - N/A

ER -