TY - JOUR
T1 - Agreement between circulating IGF-I, IGFBP-1 and IGFBP-3 levels measured by current assays versus unavailable assays previously used in epidemiological studies
AU - Aneke-Nash, Chino S.
AU - Dominguez-Islas, Clara
AU - Bůžková, Petra
AU - Qi, Qibin
AU - Xue, Xiaonan
AU - Pollak, Michael
AU - Strickler, Howard D.
AU - Kaplan, Robert C.
N1 - Funding Information:
Funding Source: The project described was supported by the MSTP Training Grant, T32-GM007288 and by the National Center for Advancing Translational Sciences (NCATS), a component of the National Institutes of Health (NIH), through CTSA grant numbers UL1TR000086, TL1RR000087, and KL2TR000088. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIH. Additional support by contracts HHSN268201200036C, N01HC85239, N01 HC55222, N01HC85079, N01HC85080, N01HC85081, N01HC85082, N01HC85083, N01HC85086, and grant HL080295 from the National Heart, Lung, and Blood Institute (NHLBI), with additional contribution from the National Institute of Neurological Disorders and Stroke (NINDS). Additional support was provided by AG023629 from the National Institute on Aging [27]. A full list of principal CHS investigators and institutions can be found at http://www.chs-nhlbi.org.
Funding Information:
Funding Source: The project described was supported by the MSTP Training Grant, T32-GM007288 and by the National Center for Advancing Translational Sciences (NCATS), a component of the National Institutes of Health (NIH), through CTSA grant numbers UL1TR000086 , TL1RR000087 , and KL2TR000088 . Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIH. Additional support by contracts HHSN268201200036C , N01HC85239 , N01 HC55222 , N01HC85079 , N01HC85080 , N01HC85081 , N01HC85082 , N01HC85083 , N01HC85086 , and grant HL080295 from the National Heart, Lung, and Blood Institute (NHLBI) , with additional contribution from the National Institute of Neurological Disorders and Stroke (NINDS). Additional support was provided by AG023629 from the National Institute on Aging [27] . A full list of principal CHS investigators and institutions can be found at http://www.chs-nhlbi.org .
Publisher Copyright:
© 2015 Elsevier Ltd.
PY - 2016/2/1
Y1 - 2016/2/1
N2 - Objective: Levels of insulin-like growth factor (IGF) proteins are associated with the risk of cancer and mortality. IGF assays produced by Diagnostic Systems Laboratories (DSL) were widely used in epidemiological studies, were not calibrated against recommended standards and are no longer commercially available. Design: In a split sample study among 1471 adults participating in the Cardiovascular Health Study, we compared values obtained using DSL assays with alternative assays for serum IGF-I (Immunodiagnostic Systems, IDS), IGFBP-1 (American Laboratory Products Company, ALPCO) and IGFBP-3 (IDS). Results: Results were compared using kernel density estimation plots, quartile analysis with weighted kappa statistics and linear regression models to assess the concordance of data from the different assays. Participants had a mean age of 77 years. Results between alternative assays were strongly correlated (IGF-I, r = 0.93 for DSL versus IDS; log-IGFBP-1, r = 0.90 for DSL versus ALPCO; IGFBP-3, r = 0.92 for DSL versus IDS). Cross tabulations showed that participants were usually in the same quartile categories regardless of the assay used (overall agreement, 74% for IGF-I, 64% for IGFBP-1, 71% for IGFBP-3). Weighted kappa also showed substantial agreement between assays (kw, 0.78 for IGF-I, 0.69 for IGFBP-1, 0.76 for IGFBP-3). Regressions of levels obtained with DSL assays (denoted X) to alternative assays were, IGF-I: 0.52X + 15.2 ng/ml, log-IGFBP-1: 1.01X - 1.73 ng/ml IGFBP-3: 0.87X + 791.1 ng/ml. Serum values of IGF-I, IGFBP-1 and IGFBP-3 measured using alternative assays are moderately correlated. Conclusions: Care is needed in the interpretation of data sets involving IGF analytes if assay methodologies are not uniform.
AB - Objective: Levels of insulin-like growth factor (IGF) proteins are associated with the risk of cancer and mortality. IGF assays produced by Diagnostic Systems Laboratories (DSL) were widely used in epidemiological studies, were not calibrated against recommended standards and are no longer commercially available. Design: In a split sample study among 1471 adults participating in the Cardiovascular Health Study, we compared values obtained using DSL assays with alternative assays for serum IGF-I (Immunodiagnostic Systems, IDS), IGFBP-1 (American Laboratory Products Company, ALPCO) and IGFBP-3 (IDS). Results: Results were compared using kernel density estimation plots, quartile analysis with weighted kappa statistics and linear regression models to assess the concordance of data from the different assays. Participants had a mean age of 77 years. Results between alternative assays were strongly correlated (IGF-I, r = 0.93 for DSL versus IDS; log-IGFBP-1, r = 0.90 for DSL versus ALPCO; IGFBP-3, r = 0.92 for DSL versus IDS). Cross tabulations showed that participants were usually in the same quartile categories regardless of the assay used (overall agreement, 74% for IGF-I, 64% for IGFBP-1, 71% for IGFBP-3). Weighted kappa also showed substantial agreement between assays (kw, 0.78 for IGF-I, 0.69 for IGFBP-1, 0.76 for IGFBP-3). Regressions of levels obtained with DSL assays (denoted X) to alternative assays were, IGF-I: 0.52X + 15.2 ng/ml, log-IGFBP-1: 1.01X - 1.73 ng/ml IGFBP-3: 0.87X + 791.1 ng/ml. Serum values of IGF-I, IGFBP-1 and IGFBP-3 measured using alternative assays are moderately correlated. Conclusions: Care is needed in the interpretation of data sets involving IGF analytes if assay methodologies are not uniform.
KW - Diabetes
KW - Glycemic status
KW - Insulin-like growth factor
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U2 - 10.1016/j.ghir.2015.12.007
DO - 10.1016/j.ghir.2015.12.007
M3 - Article
C2 - 26774400
AN - SCOPUS:84958743286
SN - 1096-6374
VL - 26
SP - 11
EP - 16
JO - Growth Hormone and IGF Research
JF - Growth Hormone and IGF Research
ER -
