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Thyrotropin levels and risk of fatal coronary heart disease: the HUNT study

Bjørn O Asvold1, Trine Bjøro, Tom Ivar L Nilsen

  • 1Department of Public Health, Faculty of Medicine, Norwegian University of Science and Technology, N-7489 Trondheim, Norway. bjorn.o.asvold@ntnu.no

Archives of Internal Medicine
|April 30, 2008
PubMed

Insights

Thyroid stimulating hormone (TSH) levels within the normal range are linked to increased risk of fatal coronary heart disease (CHD), especially in women. This suggests subclinical hypothyroidism may contribute to cardiovascular mortality.

Area of Science:

  • Endocrinology
  • Cardiovascular Disease Epidemiology

Background:

  • Suboptimal thyroid function within reference ranges is linked to coronary heart disease (CHD) risk factors.
  • The association between thyroid function and CHD mortality remains unclear.

Purpose of the Study:

  • To investigate the prospective association between thyrotropin (TSH) levels and fatal CHD.
  • To determine if TSH levels within the clinical reference range predict CHD mortality in a general population.

Main Methods:

  • A Norwegian population-based cohort study.
  • Prospective analysis of 17,311 women and 8002 men without pre-existing thyroid, cardiovascular, or diabetes conditions.
  • Median follow-up of 8.3 years, assessing thyrotropin levels and CHD mortality.

Main Results:

  • A positive association was observed between TSH levels within the reference range (0.50-3.5 mIU/L) and CHD mortality (P for trend = .01).
  • This trend was statistically significant in women (P for trend = .005).
  • Women with higher TSH levels within the reference range had significantly increased hazard ratios for coronary death.

Conclusions:

  • Thyrotropin levels within the clinical reference range show a positive, linear association with CHD mortality in women.
  • Clinically normal thyroid function, indicated by TSH levels within the reference range, may elevate the risk of fatal coronary heart disease.
Abstract

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