Langen VL, et al. - The aim of this study was to explore the correlations of Thyroid-stimulating hormone with these outcomes in a nationwide population-based prospective cohort study. Researchers exhibited evidence that thyroid function abnormalities could be linked with higher risks of total mortality and sudden cardiac death. Moreover, large-scale randomised studies are required for evidence-based recommendations regarding treatment of mild thyroid failure.

Methods

• Researchers evaluated 5211 participants representative of the Finnish population aged ≥30 years in 2000–2001 and followed them for a median of 13.2 years.
• They evaluated the associations of continuous baseline TSH and TSH categories (low [3.4 mU/L]) with incident total mortality, SCD, coronary heart disease events, stroke, CVD, major adverse cardiac events and atrial fibrillation applying Cox proportional hazards regression models adjusted for baseline age, gender, smoking, diabetes, systolic blood pressure and total and high-density lipoprotein cholesterol.

Results

• The evidence showed that high TSH at baseline was related to a greater risk of total mortality (HR 1.34, 95% CI 1.02–1.76) and SCD (HR 2.28, 95% CI 1.13–4.60) compared with TSH within the reference range.
• It was noted that high TSH was not correlated with the other outcomes (P≥0.51) whereas low TSH was not associated with any of the outcomes (P≥0.09).
• The obtained data indicates that TSH at baseline over the full range did not have a linear relation with any of the outcomes (P≥0.17).
• In addition, TSH displayed a U-shaped association with total mortality after a restricted cubic spline transformation (P=0.01).