Subclinical hyperthyroidism is a term used by the clinicians for abnormality in a thyroid gland test suggesting its high functioning however there are no symptoms. In such situation, what needs to be done is mentioned here.
Subclinical Hyperthyroidism: Podcast
What exactly is "Subclinical Hyperthyroidism"?
Subclinical hyperthyroidism is a condition where your thyroid is showing signs of potential trouble, but your main thyroid hormones (T3 and T4) are still at normal levels. Specifically, this condition is defined by a low level of Thyroid Stimulating Hormone (TSH), while the T3 and T4 levels remain normal. People who have this condition are usually asymptomatic (they do not show symptoms).
If I don’t have symptoms, is this condition still important to know about?
Yes, it is very important. Compared to people with normal thyroid function, those with this condition have a 41% increase in relative all-cause mortality. The increased risk of death is typically associated with conditions like atrial fibrillation (an irregular and often rapid heart rate) and osteoporosis (weakening of the bones).
If my TSH is low, what is the first step my doctor should take?
The general principle for managing subclinical hyperthyroidism is to recheck your TSH level in 2 to 4 months. If the TSH remains persistently low or normal, the doctor will check to see if there is a cause for the low TSH that is not related to a thyroid disorder (a “non-thyroidal cause”)
What are some reasons my TSH might be low besides a thyroid problem?
A low TSH reading can result from several factors, including:
• Systemic Illness: Any general illness can cause “sick euthyroid syndrome,” which may result in low TSH.
• Pregnancy: Being pregnant can lead to lower TSH readings.
• Pituitary or Hypothalamic Insufficiency: Problems with these glands should be suspected if the T4 or T3 levels are at the lower end of the normal range.
• Medication Use: TSH-suppressing medications, such as thyroxine or steroids, can also make the TSH low.
When is treatment necessary for Subclinical Hyperthyroidism?
Treatment should be initiated if the TSH level is less than 0.1 AND if one or more of the following conditions or symptoms are present:
• Symptoms of hyperthyroidism.
• Atrial fibrillation.
• Unexplained weight loss.
• Osteoporosis.
• Goiter (an enlarged thyroid gland).
What types of treatments are used?
For subclinical hyperthyroidism requiring treatment, the options mentioned include Carbimazole or radioiodine therapy.
What if I have this condition but no symptoms?
If you have no symptoms of the condition, usually a simple six-monthly follow-up is sufficient.