Subclinical hypothyroidism

Dear Ask The Doctor: I have been having palpitations for the last couple of years, theyve been getting alot worse. I went in to see a cardiologist and he ordered thryoid tests. my TSH is 7.5. I know palpitations come with hypER thryoidism but could hypO thryoidism be causing it? and even then would it happen from this becouse my TSH isnt realy that bad?

Dear Cassandra:The normal reference range of Thyroid Stimulating Hormone (TSH) is 0.4 – 5.0 mIU/L, however laboratories vary slightly in their reference ranges. A TSH level of 7.5 is slightly elevated, suggesting that your thyroid gland may be underactive because an increased level of TSH is required to allow your thyroid gland to function normally. It is difficult to comment without your complete thyroid function test values, and if you are asymptomatic, this is often described as subclinical hypothyroidism. Palpitations are typically described as a symptom of hyperthyroidism, and your cardiologist performed this investigation to exclude hyperthyroidism as a cause for the palpitations. Symptoms of hypothyroidism can include: fatigue, loss of energy, lethargy, weight gain, decreased appetite, cold intolerance, dry skin, hair loss, muscle pain, joint pain, and weakness in the extremities, depression, constipation, menstrual disturbances and impaired fertility. If you have any of the above symptoms I would advise attending your your family doctor, to consider thyroid hormone replacement. If you are asymptomatic, it may be sufficient to repeat thyroid function tests in a few months, as the routine treatment of asymptomatic patients with TSH values between 5 and 10 mU/L remains controversial.