Is Hashimoto’s Disease Fatal?

Ask a Doctor

My cousin has Hashimoto’s thyroiditis and I’m worried about her. Can you die from Hashimoto’s disease?

Doctor's Response

Hashimoto’s thyroiditis can be fatal – untreated, it can cause coma or heart problems – but with treatment, the prognosis is good.

The outlook for those with Hashimoto's thyroiditis is good. While long-term thyroid hormone replacement therapy will likely be needed, with regular blood tests and monitoring of symptoms, side effects are minimal and the long-term prognosis is good.

Thyroid hormone levels are usually checked every 6-12 weeks when the medication is actively being adjusted, and 6-12 months thereafter once stable. If side effects like those noted above are occurring, you should follow-up with your physician.

Risk factors for Hashimoto's thyroiditis are:

  • Female gender: Women are 10-15 times more likely than men to develop Hashimoto's thyroiditis.
  • Family history: People who develop the condition often have a family history of Hashimoto's thyroiditis or other autoimmune disorders.
  • Excessive iodine intake: Excessive iodine intake is associated with a higher prevalence of Hashimoto's thyroiditis than is seen in people with mild iodine deficiency.
  • Radiation exposure: Radiation exposure has been shown to increase the likelihood of developing auto-antibodies to the thyroid gland.

The complications of Hashimoto's thyroiditis are the same as those of an underactive thyroid gland.

Goiter: As described above, the pituitary will try to stimulate production of thyroid hormone in an underactive thyroid gland affected by Hashimoto's thyroiditis. This may cause the gland to become enlarged. Unlike a thyroid nodule, in which only a part of the gland is enlarged, in this case the entire gland enlarges, a condition known as a goiter. Goiterous glands are usually no more than a cosmetic nuisance. However, in extreme cases, growth of the gland may cause impingement on the esophagus or the trachea, impairing swallowing and breathing, respectively.

Cardiac complications: Prolonged hypothyroidism that may result from untreated Hashimoto's thyroiditis also may be associated with an increased risk of heart disease. The heart disease may be directly related to hypothyroid effects on the heart, causing changes in contraction and rhythm that may lead to subsequent heart failure. There may also be indirect influences, such as hypercholesterolemia (an increase in "bad" cholesterol is often seen with hypothyroidism).

Psychiatric complications: Depression may occur early in Hashimoto's thyroiditis and if underlying depression exists, the addition of Hashimoto's may worsen the condition. Patients may complain of mental fogginess or slowing of reaction times, and a decrease in sexual desire is often observed.

Myxedema coma: In its severest form, untreated hypothyroidism may result in a rare life-threatening condition called myxedema or myxedema coma. There is mental slowing, profound lethargy, and ultimately coma. This is a life-threatening emergency.

Lee, S. MD. "Hashimoto Thyroiditis." Medscape. Sep 08, 2015.