title: Relation of thyroid hormone abnormalities with subclinical inflammatory activity in patients with type 1 and type 2 diabetes mellitus.
abstract: Thyroid hormone (TH) abnormalities are common in patients with diabetes mellitus (DM). These thyroid hormone abnormalities have been associated with inflammatory activity in several conditions but this link remains unclear in DM. We assessed the influence of subclinical inflammation in TH metabolism in euthyroid diabetic patients. Cross-sectional study involving 258 subjects divided in 4 groups: 70 patients with T2DM and 55 patients with T1DM and two control groups of 70 and 63 non-diabetic individuals, respectively. Groups were paired by age, sex, and body mass index (BMI). We evaluated the association between clinical and hormonal variables [thyrotropin, reverse T3 (rT3), total and free thyroxine (T4), and triiodothyronine (T3)] with the inflammation markers C-reactive protein (hs-CRP), serum amyloid A (SAA), and interleukin-6 (IL-6). Serum T3 and free T3 were lower in patients with diabetes (all P < 0.001) compared to the control groups. Interleukin-6 showed positive correlations with rT3 in both groups (P < 0.05). IL-6 was independently associated to FT3/rT3 (B = -0.193; 95% CI -0.31; -0.076; P = 0.002) and FT4/rT3 (B = -0.107; 95% CI -0.207; -0.006; P = 0.039) in the T1DM group. In the T2DM group, SAA (B = 0.18; 95% CI 0.089; 0.271; P < 0.001) and hs-CRP (B = -0.069; 95% CI -0.132; -0.007; P = 0.03) predicted FT3 levels. SAA (B = -0.16; 95% CI -0.26; -0.061; P = 0.002) and IL6 (B = 0.123; 95% CI 0.005; 0.241; P = 0.041) were related to FT4/FT3. In DM, differences in TH levels compared to non-diabetic individuals were related to increased subclinical inflammatory activity and BMI. Altered deiodinase activity was probably involved. These findings were independent of sex, age, BMI, and HbA1c levels.
authors.affiliation: Division of Endocrinology, Clinical Medicine Department, Faculty of Medical Sciences, University of Campinas, UNICAMP, Rua Tessalia Vieira de Camargo, 126 - Barao Geraldo, CEP 13084-971, Campinas, Sao Paulo, Brazil.
authors.forename: Arnaldo
authors.initials: A
authors.lastname: Moura Neto
authors.affiliation: Division of Endocrinology, Clinical Medicine Department, Faculty of Medical Sciences, University of Campinas, UNICAMP, Rua Tessalia Vieira de Camargo, 126 - Barao Geraldo, CEP 13084-971, Campinas, Sao Paulo, Brazil.
authors.forename: Maria Candida Ribeiro
authors.initials: MC
authors.lastname: Parisi
authors.affiliation: Division of Internal Medicine, Clinical Medicine Department, Faculty of Medical Sciences, University of Campinas, Campinas, Sao Paulo, Brazil.
authors.forename: Sarah Monte
authors.initials: SM
authors.lastname: Alegre
authors.affiliation: Division of Endocrinology, Clinical Medicine Department, Faculty of Medical Sciences, University of Campinas, UNICAMP, Rua Tessalia Vieira de Camargo, 126 - Barao Geraldo, CEP 13084-971, Campinas, Sao Paulo, Brazil.
authors.forename: Elizabeth Joao
authors.initials: EJ
authors.lastname: Pavin
authors.affiliation: Division of Endocrinology, Clinical Medicine Department, Faculty of Medical Sciences, University of Campinas, UNICAMP, Rua Tessalia Vieira de Camargo, 126 - Barao Geraldo, CEP 13084-971, Campinas, Sao Paulo, Brazil.
authors.forename: Marcos Antonio
authors.initials: MA
authors.lastname: Tambascia
authors.affiliation: Division of Endocrinology, Clinical Medicine Department, Faculty of Medical Sciences, University of Campinas, UNICAMP, Rua Tessalia Vieira de Camargo, 126 - Barao Geraldo, CEP 13084-971, Campinas, Sao Paulo, Brazil. zantutw@fcm.unicamp.br.
authors.forename: Denise Engelbrecht
authors.initials: DE
authors.lastname: Zantut-Wittmann
mesh_terms: D000328:Adult; D058070:Asymptomatic Diseases; D002097:C-Reactive Protein / Q000378:metabolism; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000150:complications* / Q000453:epidemiology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications* / Q000453:epidemiology; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood / Q000150:complications* / Q000453:epidemiology; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D008875:Middle Aged; D000685:Serum Amyloid A Protein / Q000378:metabolism; D013959:Thyroid Diseases / Q000097:blood / Q000150:complications* / Q000453:epidemiology; D013960:Thyroid Function Tests; D013963:Thyroid Hormones / Q000097:blood*; D014285:Triiodothyronine, Reverse / Q000097:blood; D055815:Young Adult
chemical_list: C508600:IL6 protein, human; D015850:Interleukin-6; D000685:Serum Amyloid A Protein; D013963:Thyroid Hormones; D014285:Triiodothyronine, Reverse; D002097:C-Reactive Protein
keywords: Diabetes mellitus; Inflammation; Low T3; Non-thyroidal illness; Thyroid hormone metabolism