Reference intervals for insulin-like growth factor-1 (igf-i) from birth to senescence: results from a multicenter study using a new automated chemiluminescence IGF-I immunoassay conforming to recent international recommendations

Measurement of IGF-I is a cornerstone in diagnosis and monitoring of GH-related diseases, but considerable discrepancies exist between analytical methods. A recent consensus conference defined criteria for validation of IGF-I assays and for establishment of normative data. Our objectives were develo...

Full description

Saved in:
Bibliographic Details
Published in:The journal of clinical endocrinology and metabolism Vol. 99; no. 5; p. 1712
Main Authors: Bidlingmaier, Martin, Friedrich, Nele, Emeny, Rebecca T, Spranger, Joachim, Wolthers, Ole D, Roswall, Josefine, Körner, Antje, Obermayer-Pietsch, Barbara, Hübener, Christoph, Dahlgren, Jovanna, Frystyk, Jan, Pfeiffer, Andreas F H, Doering, Angela, Bielohuby, Maximilian, Wallaschofski, Henri, Arafat, Ayman M
Format: Journal Article
Language:English
Published: United States 01.05.2014
Subjects:
Adolescent
Adult
Aged
Aged, 80 and over
Aging - blood
Child
Child, Preschool
Female
Humans
Immunoassay - methods
Infant
Infant, Newborn
Insulin-Like Growth Factor I - analysis
Insulin-Like Growth Factor I - metabolism
Luminescent Measurements - methods
Male
Middle Aged
Reference Values
ISSN:1945-7197, 1945-7197
Online Access:Get more information
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Measurement of IGF-I is a cornerstone in diagnosis and monitoring of GH-related diseases, but considerable discrepancies exist between analytical methods. A recent consensus conference defined criteria for validation of IGF-I assays and for establishment of normative data. Our objectives were development and validation of a novel automated IGF-I immunoassay (iSYS; Immunodiagnostic Systems) according to international guidelines and establishment of method-specific age- and sex-adjusted reference intervals and analysis of their robustness. We conducted a multicenter study with samples from 12 cohorts from the United States, Canada, and Europe including 15 014 subjects (6697 males and 8317 females, 0-94 years of age). We measured concentrations of IGF-I as determined by the IDS iSYS IGF-I assay. A new IGF-I assay calibrated against the recommended standard (02/254) and insensitive to the 6 high-affinity IGF binding proteins was developed and rigorously validated. Age- and sex-adjusted reference intervals derived from a uniquely large cohort reflect the age-related pattern of IGF-I secretion: a decline immediately after birth followed by an increase until a pubertal peak (at 15 years of age). Later in life, values decrease continuously. The impact of gender is small, although across the lifespan, women have lower mean IGF-I concentrations. Geographical region, sampling setting (community or hospital based), and rigor of exclusion criteria in our large cohort did not affect the reference intervals. Using large cohorts of well-characterized subjects from different centers allowed construction of robust reference ranges for a new automated IGF-I assay. The strict adherence to recent consensus criteria for IGF-I assays might facilitate clinical application of the results.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
ObjectType-Undefined-3
ISSN:1945-7197
1945-7197
DOI:10.1210/jc.2013-3059