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Thyroid hormone within the normal range is associated with left ventricular mass in patients with hypertension

Masato Iida1, Mitsuru Yamamoto, Yuuko Ishiguro

  • 1Department of Cardiology, Mitsubishi Nagoya Hospital, Nagoya, Japan. masato2_iida@mhi.co.jp

Journal of the American Society of Hypertension : JASH
|June 6, 2012
PubMed

Insights

Thyroid hormone levels within the normal range correlate with left ventricular mass in hypertensive patients. Euthyroid individuals show thyroid hormone association with cardiac remodeling, independent of kidney function.

Area of Science:

  • Cardiology
  • Endocrinology
  • Hypertension Research

Background:

  • Thyroid hormone significantly influences cardiac myocyte hypertrophy.
  • Subtle alterations in thyroid hormone levels can impact cardiac function.
  • The relationship between normal thyroid hormone levels and cardiac structure in hypertension is not fully understood.

Purpose of the Study:

  • To investigate the association between thyroid hormone levels within the normal reference range and left ventricular mass in hypertensive subjects.
  • To explore the independent role of thyroid hormone in cardiac remodeling among hypertensive patients with normal thyroid function.

Main Methods:

  • Echocardiography was used to measure left ventricular mass indexed by body surface area (LVMI).
  • Thyroid stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4) were measured in 318 hypertensive patients.
  • Multiple linear regression analysis was employed, adjusting for covariates including age, gender, BMI, GFR, log BNP, systolic BP, antihypertensive medication use, and HbA1c.

Main Results:

  • In 293 euthyroid patients with normal thyroid hormone levels, fT3 (β = 0.13) and fT4 (β = 0.11) showed a positive correlation with LVMI.
  • TSH levels demonstrated an inverse correlation with LVMI (β = -0.15).
  • These associations remained significant after adjusting for renal function, cardiac dysfunction markers, and other clinical factors.

Conclusions:

  • Thyroid hormone levels within the normal euthyroid range are associated with left ventricular mass in hypertensive patients.
  • Thyroid hormone may play a role in left ventricular remodeling independently of renal and left ventricular dysfunction in this population.

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