Comparisons of immunoassay and mass spectrometry measurements of serum estradiol levels and their influence on clinical association studies in men.
J Clin Endocrinol Metab
; 98(6): E1097-102, 2013 Jun.
Article
em En
| MEDLINE
| ID: mdl-23633197
ABSTRACT
CONTEXT Immunoassay-based techniques, routinely used to measure serum estradiol (E2), are known to have reduced specificity, especially at lower concentrations, when compared 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 ANDSETTING:
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 OUTCOMEMEASURES:
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.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Espectrometria de Massas
/
Imunoensaio
/
Estradiol
Tipo de estudo:
Risk_factors_studies
Limite:
Aged
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
J Clin Endocrinol Metab
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Suécia