title: The Relationship Between Thyroid Function and the Prevalence of Type 2 Diabetes Mellitus in Euthyroid Subjects.
abstract: Thyroid hormones (THs) are primarily responsible for the regulation of energy balance and metabolism, suggesting that TH levels may contribute to the development of type 2 diabetes mellitus (T2DM). However, few studies have investigated the relationship between TH and T2DM in a general population. The aim of this study was to evaluate whether serum TH levels within the reference range are related to T2DM.
  
  
  
  A cross-sectional study (n = 15,296) was performed in Tianjin, China. Serum free triiodothyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH) levels were measured by chemiluminescence immunoassay, and T2DM was defined according to the American Diabetes Association criteria. Multiple logistic regression models were used to assess the sex-specific relationships between FT3, FT4, FT3/FT4 ratios, and TSH quintiles and T2DM.
  
  
  
  The prevalence of T2DM was 16.2% in males and 7.7% in females. In males, the multivariable-adjusted odds ratios (95% confidence interval) of T2DM for increasing quintiles of FT3, FT4, and FT3/FT4 ratios were 1.00, 0.75(0.63 to 0.89), 0.70(0.58 to 0.84), 0.63(0.52 to 0.76), 0.56(0.46 to 0.68; P for trend < 0.0001); 1.00, 1.05(0.87 to 1.27), 1.16(0.96 to 1.40), 1.09(0.90 to 1.31), 1.29(1.07 to 1.56; P for trend = 0.01); and 1.00, 0.69(0.58 to 0.83), 0.72(0.60 to 0.86), 0.59(0.48 to 0.71), and 0.55(0.46 to 0.66; P for trend < 0.0001), respectively. Similar results also were observed in females. In contrast, a strong negative correlation between TSH and T2DM was observed in males, but not in females.
  
  
  
  This study demonstrated that decreased FT3, FT3/FT4 ratios, and increased FT4 levels are independently related to a higher prevalence of T2DM in both males and females, and TSH is inversely related to T2DM in males only.
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Yeqing
authors.initials: Y
authors.lastname: Gu
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Huihui
authors.initials: H
authors.lastname: Li
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Xue
authors.initials: X
authors.lastname: Bao
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, 300070 Tianjin, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, 300070 Tianjin, China.
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Ge
authors.initials: G
authors.lastname: Meng
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Hongmei
authors.initials: H
authors.lastname: Wu
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Huanmin
authors.initials: H
authors.lastname: Du
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, 300070 Tianjin, China.
authors.forename: Hongbin
authors.initials: H
authors.lastname: Shi
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Yang
authors.initials: Y
authors.lastname: Xia
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Qian
authors.initials: Q
authors.lastname: Su
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Liyun
authors.initials: L
authors.lastname: Fang
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Fei
authors.initials: F
authors.lastname: Yu
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Huijun
authors.initials: H
authors.lastname: Yang
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Bin
authors.initials: B
authors.lastname: Yu
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, 300070 Tianjin, China.
authors.forename: Shaomei
authors.initials: S
authors.lastname: Sun
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, 300070 Tianjin, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Wang
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, 300070 Tianjin, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Zhou
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, 300070 Tianjin, China.
authors.forename: Qiyu
authors.initials: Q
authors.lastname: Jia
authors.affiliation: Department of Rehabilitation and Sports Medicine Tianjin Medical University, 300070 Tianjin, China; and.
authors.forename: Qi
authors.initials: Q
authors.lastname: Guo
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Hong
authors.initials: H
authors.lastname: Chang
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, 300070 Tianjin, China.
authors.forename: Guolin
authors.initials: G
authors.lastname: Wang
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.
authors.forename: Guowei
authors.initials: G
authors.lastname: Huang
authors.affiliation: Health Management Centre, Tianjin Medical University General Hospital, 300070 Tianjin, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Song
authors.affiliation: Nutritional Epidemiology Institute and School of Public Health, and.|Health Management Centre, Tianjin Medical University General Hospital, 300070 Tianjin, China.
authors.forename: Kaijun
authors.initials: K
authors.lastname: Niu
mesh_terms: D000328:Adult; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000453:epidemiology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012737:Sex Factors; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000503:physiopathology*; D013963:Thyroid Hormones / Q000097:blood*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood; D055815:Young Adult
chemical_list: D013963:Thyroid Hormones; D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine