TY - JOUR
T1 - Comparisons of immunoassay and mass spectrometry measurements of serum estradiol levels and their influence on clinical association studies in men
AU - Ohlsson, Claes
AU - Nilsson, Maria E.
AU - Tivesten, Åsa
AU - Ryberg, Henrik
AU - Mellström, Dan
AU - Karlsson, Magnus K.
AU - Ljunggren, Östen
AU - Labrie, Fernand
AU - Orwoll, Eric S.
AU - Lee, David M.
AU - Pye, Stephen R.
AU - O'Neill, Terence W.
AU - Finn, Joseph D.
AU - Adams, Judith E.
AU - Ward, Kate A.
AU - Boonen, Steven
AU - Bartfai, Gyorgy
AU - Casanueva, Felipe F.
AU - Forti, Gianni
AU - Giwercman, Aleksander
AU - Han, Thang S.
AU - Huhtaniemi, Ilpo T.
AU - Kula, Krzysztof
AU - Lean, Michael E J
AU - Pendleton, Neil
AU - Punab, Margus
AU - Vanderschueren, Dirk
AU - Wu, Frederick C W
AU - Vandenput, Liesbeth
AU - Petrone, Luisa
AU - Corona, Giovanni
AU - Borghs, Herman
AU - Slowikowska-Hilczer, Jolanta
AU - Walczak-Jedrzejowska, Renata
AU - Silman, Alan
AU - Steer, Philip
AU - Lage, Mary
AU - Castro, Ana I.
AU - Földesi, Imre
AU - Fejes, Imre
AU - Korrovitz, Paul
AU - Jiang, Min
PY - 2013/6
Y1 - 2013/6
N2 - Context: Immunoassay-based techniques, routinely used to measure serum estradiol (E2), are known to have reduced specificity, especially at lower concentrations,whencompared with the gold standard technique of mass spectrometry (MS). Different measurement techniques may be responsible for the conflicting results of associations between serum E2 and clinical phenotypes in men. Objective: Our objective was to compare immunoassay and MS measurements of E2 levels in men and evaluate associations with clinical phenotypes. Design and Setting: Middle-aged and older male subjects participating in the population-based Osteoporotic Fractures in Men (MrOS) Sweden study (n = 2599), MrOS US (n = 688), and the European Male Aging Study (n = 2908) were included. Main Outcome Measures: Immunoassay and MS measurements of serum E2 were compared and related to bone mineral density (BMD; measured by dual energy x-ray absorptiometry) and ankle-brachial index. Results: Within each cohort, serum E2 levels obtained by immunoassay and MS correlated moderately (Spearman rank correlation coefficient rS 0.53-0.76). Serum C-reactive protein (CRP) levels associated significantly (albeit to a low extent, rS = 0.29) with immunoassay E2 but not with MS E2 levels. Similar associations of immunoassay E2 and MS E2 were seen with lumbar spine and total hip BMD, independent of serum CRP. However, immunoassay E2, but not MS E2, associated inversely with ankle-brachial index, and this correlation was lost after adjustment for CRP. Conclusions: Our findings suggest interference in the immunoassay E2 analyses, possibly by CRP or a CRP-associated factor. Although associations with BMD remain unaffected, this might imply for a reevaluation of previous association studies between immunoassay E2 levels and inflammation-related outcomes. Copyright © 2013 by The Endocrine Society.
AB - Context: Immunoassay-based techniques, routinely used to measure serum estradiol (E2), are known to have reduced specificity, especially at lower concentrations,whencompared with the gold standard technique of mass spectrometry (MS). Different measurement techniques may be responsible for the conflicting results of associations between serum E2 and clinical phenotypes in men. Objective: Our objective was to compare immunoassay and MS measurements of E2 levels in men and evaluate associations with clinical phenotypes. Design and Setting: Middle-aged and older male subjects participating in the population-based Osteoporotic Fractures in Men (MrOS) Sweden study (n = 2599), MrOS US (n = 688), and the European Male Aging Study (n = 2908) were included. Main Outcome Measures: Immunoassay and MS measurements of serum E2 were compared and related to bone mineral density (BMD; measured by dual energy x-ray absorptiometry) and ankle-brachial index. Results: Within each cohort, serum E2 levels obtained by immunoassay and MS correlated moderately (Spearman rank correlation coefficient rS 0.53-0.76). Serum C-reactive protein (CRP) levels associated significantly (albeit to a low extent, rS = 0.29) with immunoassay E2 but not with MS E2 levels. Similar associations of immunoassay E2 and MS E2 were seen with lumbar spine and total hip BMD, independent of serum CRP. However, immunoassay E2, but not MS E2, associated inversely with ankle-brachial index, and this correlation was lost after adjustment for CRP. Conclusions: Our findings suggest interference in the immunoassay E2 analyses, possibly by CRP or a CRP-associated factor. Although associations with BMD remain unaffected, this might imply for a reevaluation of previous association studies between immunoassay E2 levels and inflammation-related outcomes. Copyright © 2013 by The Endocrine Society.
U2 - 10.1210/jc.2012-3861
DO - 10.1210/jc.2012-3861
M3 - Article
C2 - 23633197
SN - 1945-7197
VL - 98
SP - E1097-E1102
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
IS - 6
ER -