R Tozzoli1, F D'Aurizio2, P Metus1, A Steffan3, C Mazzon4, M Bagnasco5. 1. Clinical Pathology Laboratory, Department of Laboratory Medicine, Azienda per l'Assistenza Sanitaria n. 5, Friuli Occidentale, Pordenone Hospital, Pordenone, Italy. 2. Institute of Clinical Pathology, Azienda Sanitaria Universitaria Integrata di Udine, Udine, Italy. federica.daurizio@asuiud.sanita.fvg.it. 3. Immunopathology and Tumor Biomarkers Laboratory, National Cancer Institute, Aviano Hospital, Aviano, Italy. 4. Endocrinology Unit, Department of Internal Medicine, Azienda per l'Assistenza Sanitaria n. 5, Friuli Occidentale, Pordenone Hospital, Pordenone, Italy. 5. Endocrinology and Autoimmunity Laboratory, Department of Internal Medicine, IRCCS Azienda Ospedaliera Universitaria San Martino-IST Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy.
Abstract
PURPOSE: Thyrotropin (TSH) is the most accurate marker of thyroid dysfunction in the absence of pituitary or hypothalamic disease. Studies on TSH reference intervals (RIs) showed wide inter-individual variability and prompted an intense debate about the best estimation of TSH RIs. DESIGN: We performed a population study on TSH RIs, using current data stored in the laboratory information system (LIS), at the Hospital Department of Laboratory Medicine, Pordenone (Italy), historically an area of mild-moderate iodine deficiency with a relatively high goiter prevalence. METHODS: 136,650 individuals constituted the final sample. A TSH immunoassay was performed on fasting serum samples with the Dimension Vista 1500 analyzer (Siemens Healthineers). We adopted the Kairisto's procedure to analyze TSH data downloaded by the LIS, applying the indirect strategy for deriving RIs. RESULTS: TSH RIs of the entire population were 0.32-3.36 mIU/L with a distribution skewed towards higher values. RIs were 0.26-3.61 mIU/L for females, and 0.32-3.01 mIU/L for males. Unlike other studies, TSH median levels progressively decreased from 0-4 to 85-104 years in the overall population, both in male and in female subgroups, showing an inverse correlation between TSH and age in all groups. CONCLUSIONS: This study is the first to analyze a high percentage (40%) of individuals from an ethnically homogenous Caucasian population. The results obtained emphasize the opportunity to define the TSH RIs according to age, gender and race, in addition to assay methods, and provide further insight about the possible role of iodine status.
PURPOSE: Thyrotropin (TSH) is the most accurate marker of thyroid dysfunction in the absence of pituitary or hypothalamic disease. Studies on TSH reference intervals (RIs) showed wide inter-individual variability and prompted an intense debate about the best estimation of TSH RIs. DESIGN: We performed a population study on TSH RIs, using current data stored in the laboratory information system (LIS), at the Hospital Department of Laboratory Medicine, Pordenone (Italy), historically an area of mild-moderate iodine deficiency with a relatively high goiter prevalence. METHODS: 136,650 individuals constituted the final sample. A TSH immunoassay was performed on fasting serum samples with the Dimension Vista 1500 analyzer (Siemens Healthineers). We adopted the Kairisto's procedure to analyze TSH data downloaded by the LIS, applying the indirect strategy for deriving RIs. RESULTS: TSH RIs of the entire population were 0.32-3.36 mIU/L with a distribution skewed towards higher values. RIs were 0.26-3.61 mIU/L for females, and 0.32-3.01 mIU/L for males. Unlike other studies, TSH median levels progressively decreased from 0-4 to 85-104 years in the overall population, both in male and in female subgroups, showing an inverse correlation between TSH and age in all groups. CONCLUSIONS: This study is the first to analyze a high percentage (40%) of individuals from an ethnically homogenous Caucasian population. The results obtained emphasize the opportunity to define the TSH RIs according to age, gender and race, in addition to assay methods, and provide further insight about the possible role of iodine status.
Authors: Annenienke C van de Ven; Romana T Netea-Maier; Johannes W Smit; Ron Kusters; Jos W J van der Stappen; Claudia J Pronk-Admiraal; Madelon M Buijs; Christian H H Schoenmakers; Stephan G A Koehorst; Monique J M de Groot; Fred C G J Sweep; Ad R M M Hermus; Martin den Heijer Journal: Thyroid Date: 2015-04-20 Impact factor: 6.568
Authors: T Bjoro; J Holmen; O Krüger; K Midthjell; K Hunstad; T Schreiner; L Sandnes; H Brochmann Journal: Eur J Endocrinol Date: 2000-11 Impact factor: 6.664
Authors: F Aghini-Lombardi; L Antonangeli; E Martino; P Vitti; D Maccherini; F Leoli; T Rago; L Grasso; R Valeriano; A Balestrieri; A Pinchera Journal: J Clin Endocrinol Metab Date: 1999-02 Impact factor: 5.958