title: Increased leptin/adiponectin ratio relates to low-normal thyroid function in metabolic syndrome.
abstract: BACKGROUND
  Low-normal thyroid function within the euthyroid range may contribute to increased atherosclerosis susceptibility. The leptin/adiponectin (L/A) ratio is associated with cardiovascular disease and reflects adipose tissue dysfunction. Relationships of the L/A ratio with low-normal thyroid function are unknown.
  
  
  METHODS
  Relationships of thyroid stimulating hormone (TSH) and free thyroxine (free T4) with leptin, adiponectin and the L/A ratio in euthyroid subjects were documented in 67 fasting subjects with metabolic syndrome (Mets) and 86 euthyroid subjects without MetS (TSH and free T4levels within the institutional reference range).
  
  
  RESULTS
  Neither plasma leptin nor adiponectin was significantly correlated with TSH or free T4in subjects with and without MetS. In the whole group, high sensitivity C-reactive protein (hs-CRP) was positively correlated with the L/A ratio (r = 0.485, P < 0.001). Notably, the L/A ratio was positively correlated with TSH in subjects with MetS (r = 0.252, P = 0.040) but not in subjects without MetS (r = -0.068, P = 0.54; interaction term, P = 0.027). In MetS subjects, the L/A ratio remained positively related with TSH after adjustment for age, sex, diabetes status, hs-CRP and the use of antihypertensive and glucose lowering medication (β = 0.283, P = 0.018), as well as after adjustment for individual MetS components (β = 0.294, P = 0.020).
  
  
  CONCLUSIONS
  In the context of MetS, a higher TSH within the euthyroid range confers an increased L/A ratio, a proposed marker of atherosclerosis susceptibility and adipocyte dysfunction.
authors.affiliation: Department of Endocrinology, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands. L.J.N.van.Tienhoven-Wind@umcg.nl.
authors.forename: Lynnda J N
authors.initials: LJ
authors.lastname: van Tienhoven-Wind
authors.affiliation: Department of Endocrinology, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Robin P F
authors.initials: RP
authors.lastname: Dullaart
mesh_terms: D017667:Adipocytes / Q000378:metabolism / Q000473:pathology; D052242:Adiponectin / Q000097:blood / Q000235:genetics*; D000273:Adipose Tissue / Q000378:metabolism* / Q000473:pathology; D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use; D050197:Atherosclerosis / Q000175:diagnosis; D002097:C-Reactive Protein / Q000235:genetics / Q000378:metabolism; D003430:Cross-Sectional Studies; D005215:Fasting; D005260:Female; D005786:Gene Expression Regulation; D020022:Genetic Predisposition to Disease; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D020738:Leptin / Q000097:blood / Q000235:genetics*; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000188:drug therapy / Q000235:genetics* / Q000503:physiopathology; D008875:Middle Aged; D011379:Prognosis; D013961:Thyroid Gland / Q000378:metabolism / Q000503:physiopathology; D013972:Thyrotropin / Q000097:blood / Q000235:genetics*; D013974:Thyroxine / Q000097:blood / Q000235:genetics
chemical_list: C499918:ADIPOQ protein, human; D052242:Adiponectin; D000959:Antihypertensive Agents; D007004:Hypoglycemic Agents; D020738:Leptin; D013972:Thyrotropin; D002097:C-Reactive Protein; D013974:Thyroxine
keywords: Adiponectin; Leptin; Leptin/adiponectin ratio; Metabolic syndrome; Thyroid function