title: Thyroid function, as assessed by TSH, and future risk of venous thromboembolism: the Tromsø study.
abstract: OBJECTIVE
  The relationship between thyroid function and the risk of venous thromboembolism (VTE) has not been addressed in population-based cohorts. We investigated the association between TSH levels and the risk of VTE in a general adult population.
  
  
  METHODS
  Population-based cohort study.
  
  
  METHODS
  TSH was measured in 11 962 subjects aged 25-89 years who participated in Tromsø 4-6 starting in 1994-1995. Incident VTE events were recorded through 31st December 2010. Cox's regression models with TSH as a time-varying covariate were used to calculate hazard ratios (HRs) of VTE by TSH categories (low TSH: <0.05  mU/l; moderately reduced TSH: 0.05-0.19  mU/l; normal TSH: 0.20-4.00  mU/l; moderately elevated TSH: 4.01-5.00  mU/l; and high TSH: >5.00 mU/l) and within the normal range of TSH, modeling TSH as a continuous variable.
  
  
  RESULTS
  There were 289 VTEs during 8.2 years of median follow-up. Subjects with low (prevalence: 0.22%) and high (3.01%) TSH had slightly higher risk estimates for VTE than did subjects with normal TSH (multivariable HRs: 2.16, 95% CI 0.69-6.76 and 1.55, 95% CI 0.87-2.77 respectively), but the CIs were wide. Moreover, there was no association between TSH within the normal range and VTE (HR per 1 mU/l increase: 0.95, 95% CI 0.82-1.11).
  
  
  CONCLUSIONS
  Serum levels of TSH within the normal range were not associated with a risk of VTE, whereas low and high TSH levels were rare and associated with a moderately higher risk of VTE. The present findings suggest that only a minor proportion of the VTE risk in the population can be attributed to thyroid dysfunction.
authors.affiliation: Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway gunhild.lerstad@uit.no.
authors.forename: Gunhild
authors.initials: G
authors.lastname: Lerstad
authors.affiliation: Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway.
authors.forename: Kristin F
authors.initials: KF
authors.lastname: Enga
authors.affiliation: Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway.
authors.forename: Rolf
authors.initials: R
authors.lastname: Jorde
authors.affiliation: Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway.
authors.forename: Ellen E
authors.initials: EE
authors.lastname: Brodin
authors.affiliation: Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway.
authors.forename: Johan
authors.initials: J
authors.lastname: Svartberg
authors.affiliation: Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway.
authors.forename: Sigrid K
authors.initials: SK
authors.lastname: Brækkan
authors.affiliation: Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway Department of Clinical MedicineK.G. Jebsen Thrombosis Research and Expertise Center (TREC)Hematological Research Group (HERG)Department of Clinical MedicineEndocrine Research GroupDepartment of Clinical Medicine, University of Tromsø, N-9037 Tromsø, NorwayDivision of Internal MedicineUniversity Hospital of North Norway, Tromsø, Norway.
authors.forename: John-Bjarne
authors.initials: JB
authors.lastname: Hansen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D011153:Population; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D013960:Thyroid Function Tests / Q000379:methods*; D013972:Thyrotropin / Q000097:blood*; D054556:Venous Thromboembolism / Q000453:epidemiology*
chemical_list: D013972:Thyrotropin