Low thyroid tied to heart attacks

Women with a slightly underactive thyroid gland appear to be at increased risk for death from heart attacks and other types of heart diseases.Emerging evidence suggests that as thyroid function drops, blood pressure and cholesterol levels rise as does the risk of heart problems.American researchers investigated the association in a study of 17,311 female and 8002 male participants who were free of heart disease, thyroid disease, and diabetes when the study began. Subjects were over 40 years old between 1995 and 1997, when levels of thyrotropin, a hormone that gauges thyroid function, were measured. During follow-up through 2004, 192 women and 164 men died of heart disease who appeared to have normal thyroid function. That is, none of the patients had any signs or symptoms of an underactive or overactive thyroid gland. Among subjects with seemingly normal thyroid function, women with the least active glands were 69 percent more likely to die from heart disease than women with more active glands. No similar association was seen in men.No clinical trial has tested whether treatment with thyroid hormone could protect against heart disease. However, there is evidence that such treatment can reduce high blood pressure, cholesterol levels, and body weight.