Abstrakt
Background: IGF1 is responsible for regulation of growth, metabolism and differentiation of human cells. IGFBP3 is the most abundant of the carrier proteins for IGFI in the blood.
IGF1/IGFBP3 molar ratio is an indicator of IGF1 bioavailability. We decided to create a file of reference ranges of IGF1, IGFBP3 and IGF1/IGFBPP3 ratio for the adult Czech population across the age spectrum.
Methods: We selected a group of 1022 subjects, 467 males and 555 females (ages 20-98 years), from several regions in the Czech Republic. The group consisted of blood donors and patients undergoing regular preventive examinations.
Serum levels of IGF1 and IGFBP3 were measured using the following radioimmunoassay kits: IRMA IGF1 (Immunotech, Marseille, France) and IRMA IGFBP3 (Immunotech, Prague, Czech Republic). The IGF1/IGFBP3 ratio was also calculated.
The following groups of patients were excluded: patients with diabetes, high blood glucose, high insulin levels, post-surgery patients, polymorbid patients, and subjects with oncological diseases. Subjects were divided into seven age-groups.
Changes in the levels of observed analytes in each decade across the age spectrum were evaluated. All statistical analyses were performed by SAS 9.3 (Statistical Analysis Software release 9.3; SAS Institute Inc., Cary, NC, USA).
Conclusion: Authors recommend using of a linear regression model based reference ranges for IGF1, IGFBP3 and IGF1/IGFBP3 ratio and using different reference ranges for genders.