Thyroid Function and High-Sensitivity C-Reactive Protein in Cross-Sectional Results from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil): Effect of Adiposity and Insulin Resistance. Issue 4 (2nd December 2016)

• Record Type: Journal Article
• Authors: Peixoto de Miranda, Érique José F.; Bittencourt, Márcio Sommer; Santos, Itamar S.; Lotufo, Paulo A.; Benseñor, Isabela M.
• Is Part Of: European thyroid journal. Volume 5:Issue 4(2016)
• Page Start: 240
• Page End: 246
• Publication Date: 2016-12-02
• Subjects: Obesity -- Cardiovascular risk factors -- Insulin resistance -- C-reactive protein -- Subclinical hypothyroidism -- Systemic inflammation -- Thyroid dysfunction; Thyroid gland -- Diseases -- Periodicals; Thyroid Diseases -- Periodicals; 612.44
• DOI: 10.1159/000448683
• Languages: English
• ISSNs: 2235-0640

Abstract

Abstract : Background: Subclinical hypothyroidism (SCH) is associated with an increased cardiovascular risk, but little information is available about its association with high-sensitivity C-reactive protein (hs-CRP). Objectives: This study aims to analyze the association between SCH and hs-CRP using baseline data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Methods: The study has a cross-sectional design. We included subjects with normal thyroid function (thyroid-stimulating hormone, TSH, 0.4-4.0 μIU/ml and normal free thyroxine, fT4, 10.3-24.45 pmol/l) and SCH (TSH >4.0 μIU/ml and normal fT4 ) who were evaluated for hs-CRP. We excluded individuals on medications that affect thyroid function and those who had prevalent cardiovascular disease. Multivariate linear regression evaluated hs-CRP and TSH as continuous variables, and logistic regression models assessed hs-CRP ≥19.05 nmol/l as the dependent variable and crescent quintiles of TSH as the independent variables adjusted for demographic and cardiovascular risk factors. Results: We included 12, 284 subjects with a median age of 50 years (interquartile range = 45-57); 6, 408 (52.2%) were female, 11, 589 (94.3%) were euthyroid, and 695 (5.7%) had SCH. Bivariate analyses of participants stratified into quintiles of TSH revealed differences according to hs-CRP but not the Framingham risk score. The fifth quintile of TSH was not associated with elevated hs-CRP, odds ratio = 1.11 (95% confidence interval = 0.98-1.26), p = 0.102, in a fully adjusted logistic model, also consistent with the linear model (β = 0.024, p = 0.145). Conclusions: TSH is not associated with hs-CRP. Obesity and insulin resistance are very important confounders in the study of the association between SCH and hs-CRP.