title: Low serum thyrotropin is associated with high plasma fibrinogen.
abstract: BACKGROUND
  Elevated plasma fibrinogen levels are associated with an increased risk of cardiovascular events. Decreased serum TSH predicts vascular mortality, which hypothetically could be explained in part by alterations in the blood coagulation system.
  
  
  OBJECTIVE
  The objective of this study was to investigate the association between thyroid function and plasma fibrinogen levels in a general population.
  
  
  METHODS
  The population-based Study of Health in Pomerania was performed in a previously iodine-deficient area in Germany, including 4310 subjects, aged 20-79 yr. Data for 3804 individuals without thyroid disease were analyzed. Analysis revealed an association between thyroid function status and plasma fibrinogen concentration.
  
  
  RESULTS
  Elevated fibrinogen levels (>3.25 g/liter) were observed in 14 subjects with increased serum TSH levels (32.6%), 973 euthyroid subjects (28.9%), 158 subjects with decreased serum TSH levels (40.7%), and six individuals with overt hyperthyroidism (54.4%). Logistic regression analysis revealed decreased serum TSH as an independent risk factor for elevated fibrinogen levels (odds ratio, 1.42; 95% confidence interval, 1.12-1.80).
  
  
  CONCLUSIONS
  Thyroid function is associated with plasma fibrinogen. Decreased serum TSH is an independent risk factor for elevated plasma fibrinogen levels as a possible explanation for the high cardiovascular mortality among affected subjects.
authors.affiliation: Department of Internal Medicine B, Ernst Moritz Arndt University, Friedrich Loeffler Strasse 23a, D-17487 Greifswald, Germany. mdoerr@uni-greifswald.de
authors.forename: Marcus
authors.initials: M
authors.lastname: Dörr
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Robinson
authors.forename: Henri
authors.initials: H
authors.lastname: Wallaschofski
authors.forename: Christian
authors.initials: C
authors.lastname: Schwahn
authors.forename: Ulrich
authors.initials: U
authors.lastname: John
authors.forename: Stephan B
authors.initials: SB
authors.lastname: Felix
authors.forename: Henry
authors.initials: H
authors.lastname: Völzke
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005340:Fibrinogen / Q000378:metabolism*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D013961:Thyroid Gland / Q000378:metabolism / Q000502:physiology*; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D014284:Triiodothyronine; D005340:Fibrinogen; D013972:Thyrotropin; D013974:Thyroxine