The outlook for hyperthyroidism is generally quite promising, but as with most medical conditions, a number of complications can occur if left untreated. These range from eye problems and pregnancy troubles to hypothyroidism and a life-threatening condition called thyroid storm. Additional complications of the heart and the bones are also possible, including arrhythmia, cardiac dilation, congestive heart failure, sudden cardiac arrest, hypertension, and osteoporosis. The latter of these is a condition that is associated with weakened and brittle bones, making them extremely fragile and more likely to break.
Eye problems affect approximately one-third of individuals who suffer from the type of hyperthyroidism caused by Graves’ disease. These problems include dry and gritty eyes, sensitivity to light, blurred or double vision, red or watering eyes, swollen or pulled back eyelids, and bulging eyes. More often than not, the cases are mild and will improve with treatment, but there is always a slight chance of vision loss. In some instances, eye drops, steroid medicine, or surgery may be required. Eye problems such as these are fittingly known as thyroid eye disease (TED) or Graves’ ophthalmopathy.
Pregnancy troubles may arise in individuals who experience an overactive thyroid during pregnancy. If the condition is poorly controlled, there is an increased risk of pre-eclampsia, miscarriage, premature labor and birth, and giving birth to a baby with a low birthweight. Pre-eclampsia is a complication that is characterized by high blood pressure and a significant amount of protein in the urine, miscarriage refers to the loss of a pregnancy within the first 23 weeks, and premature labor is when labor happens before the 37th week of pregnancy.
The opposite of hyperthyroidism, an overactive thyroid, is hypothyroidism, an underactive thyroid. Because treatment for an overactive thyroid can result in hormone levels becoming too low, hypothyroidism is classified as a complication of hyperthyroidism. As such, symptoms of hypothyroidism include tiredness, weight gain, sensitivity to cold, constipation, and depression. Oftentimes an underactive thyroid is only temporary, especially as patients and doctors work to develop the correct dosage of thyroid hormone medicine, but some may become permanent and therefore require long-term treatment.
Thyroid storm is a very serious and life-threatening condition that occurs in rare cases where an overactive thyroid is undiagnosed or poorly controlled. The sudden flare-up of symptoms may be triggered by an infection, pregnancy, misuse of medicine, or damage to the thyroid gland. Some of the symptoms to look out for include a high temperature or rapid heartbeat, severe agitation and confusion, yellowing of the skin and eyes, diarrhea and being sick, and a loss of consciousness. This worsening of symptoms is also known as thyrotoxic crisis and requires urgent medical attention.
Given these many complications of hyperthyroidism, it is important to be proactive in treating the condition. Reasons to see a doctor include, but are not limited to, unexplained weight loss, unusual sweating, swelling at the base of the neck, and a rapid heartbeat. If diagnosed with hyperthyroidism, patients should see their doctor or nurse regularly to check thyroid hormone levels and monitor for recurrent hyperthyroidism or hypothyroidism.
Resources:
1) https://www.nhs.uk/conditions/overactive-thyroid-hyperthyroidism/complications/
2) https://www.mayoclinic.org/diseases-conditions/hyperthyroidism/symptoms-causes/syc-20373659
3) https://www.endocrineweb.com/conditions/hyperthyroidism/hyperthyroidism-complications
4) https://www.healthdirect.gov.au/complications-of-thyroid-problems