Underactive Thyroid Raises Heart Disease Risk In Women

Women with an under-active thyroid, a condition known as hypothyroidism, are at a greater risk of heart disease according to a recent study published in the April 28 issue of the journal Archives of Internal Medicine. The results of the study indicated that even women with low, but clinically normal thyroid function, are at an increased risk of heart disease.

The study, conducted by Norwegian researchers, involved the study of around 25,000 people from Norway who were initially free of heart disease, diabetes, and thyroid problems. The participants were followed for an average of 8.3 years during which 410 people died from coronary heart disease.

The researchers found that levels of thyrotropin were much lower in those who had died of coronary heart disease (CHD). Thyrotropin is produced in the pituitary gland and stimulates the growth and function of the thyroid gland. Thyrotropin levels are considered to be an accurate marker of thyroid function

Women with the lowest thyrotropin levels were 41% more likely to die from CHD than those with average thyrotropin levels and 69% more likely to die from CHD than the women with the highest thyrotropin levels. Although low thyrotropin levels were linked to a higher CHD risk in men, the association was not statistically significant.

An under-active thyroid is known to lead to weight gain, an increase in blood cholesterol levels, and hypertension (high blood pressure) which are all significant risk factors for heart disease. Extremely low thyroid function can lead to bradycardia (extremely low heart rate), depression, fatigue, muscle wasting, hair loss, and even death in rare cases.

Hypothyroidism is generally treated through the administration of the thyroid hormones thyroxine and/or triiodothyronine.