title: Evaluation of the relationship between subclinical hypothyroidism and metabolic syndrome components among workers.
abstract: OBJECTIVE
  Both hyperthyroidism and overt hypothyroidism are associated with increased prevalence of metabolic syndrome and its components, while data on subclinical hypothyroidism is currently limited especially in working populations. The aim of this study was to examine the association between subclinical hypothyroidism and metabolic syndrome components in workers; and to evaluate whether there are differences by sex and occupation.
  
  
  METHODS
  A total of 1150 university employees (male - 792, female - 358) aged 30-60 years who came for an annual medical check-up were studied. Anthropometric measurements were taken, and blood pressure, fasting plasma glucose (FPG), lipid profiles, thyroid stimulating hormone (TSH), free thyroxin (FT4) and free triiodothyronine (FT3) levels were measured.
  
  
  RESULTS
  After adjustment for age and body mass index (BMI), TSH was positively associated with increased triglyceride (TG) levels (β = 0.108, p = 0.020) and FPG (β = 0.130, p = 0.006) in subclinical hypothyroid male workers. However, TSH was not associated (p > 0.05) with any component of metabolic syndrome (MS) in the euthyroid group. In females, TSH was not correlated with MS components in both euthyroid and subclinical hypothyroid groups. Furthermore, comparison by occupation showed higher TSH in subclinical hypothyroid male workers employed in administration (5.23 ± 0.52 mU/l) than those working as academics (5.12 ± 0.52 mU/l), which resulted in elevated systolic and diastolic blood pressure, FPG, total cholesterol, TG and high density lipoprotein cholesterol. In females, BMI, systolic and diastolic blood pressure, TG and FPG were significantly (p < 0.05) higher in subclinical hypothyroid administrators than those in academics.
  
  
  CONCLUSIONS
  Subclinical hypothyroidism was associated with metabolic syndrome components in male workers and not in females. Administration workers showed increased metabolic risks compared to academics. The findings suggest that the assessment of thyroid function in individuals with metabolic syndrome in the workplace may be favorable especially among men.
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.
authors.forename: Maureen Jepkorir
authors.initials: MJ
authors.lastname: Cheserek
authors.forename: Guirong
authors.initials: G
authors.lastname: Wu
authors.forename: Liye
authors.initials: L
authors.lastname: Shen
authors.forename: Yonghui
authors.initials: Y
authors.lastname: Shi
authors.forename: Guowei
authors.initials: G
authors.lastname: Le
mesh_terms: D000328:Adult; D058070:Asymptomatic Diseases; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D008076:Cholesterol, HDL / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood* / Q000175:diagnosis; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood* / Q000175:diagnosis; D008875:Middle Aged; D012737:Sex Factors; D013663:Teaching; D013972:Thyrotropin / Q000097:blood; D014280:Triglycerides / Q000097:blood; D014495:Universities / Q000458:organization & administration
chemical_list: D001786:Blood Glucose; D008076:Cholesterol, HDL; D014280:Triglycerides; D013972:Thyrotropin