Hypothyroidism is underactive thyroid. This is a condition in which the thyroid gland does not produce enough of certain important hormones. Women are more likely to have hypothyroidism compared to men, especially those who are older than age 60 [1]. This condition upsets the normal balance of the chemical reactions in the body. Hypothyroidism seldom causes symptoms in the early stages but if you leave the hypothyroidism untreated, then it can cause many health problems such as heart disease, infertility, joint pain and obesity. There are some thyroid function tests which can help to diagnose the hypothyroidism and the treatment of this condition with synthetic thyroid hormone is usually effective, safe and simple once your doctor found the right dose for you.
Hypothyroidism signs and symptoms
The signs and symptoms of this condition can vary which depends on the severity of hormone deficiency. When we talk in general, any problem tends to develop slowly and often takes a number of years. When hypothyroidism is in the early stage, you may barely notice the symptoms of this condition such as weight gain and fatigue or you may think that you have these symptoms because you are getting older. But as your metabolism continues to slow, then you will start noticing more obvious signs and symptoms of hypothyroidism, such as
- Impaired memory
- Depression [2]
- Slowed heart rate
- Thinning hair
- Heavier than normal or irregular menstrual periods
- Pain, stiffness or swelling in your joints
- Muscle aches, tenderness and stiffness
- Elevated blood cholesterol level
- Muscle weakness
- Hoarseness
- Puffy face
- Weight gain
- Dry skin
- Constipation
- Increased sensitivity to cold
- Fatigue
When this condition is not treated, then the signs and symptoms can gradually become more severe. The constant stimulation of the thyroid gland to release more hormones can lead to goiter (enlarged thyroid). Also you can feel depressed, your thought to processes may slow or you may become more forgetful [2]. The advanced hypothyroidism is known as myxedema. This is a rare condition but when it happens, then it can be life – threatening. The signs and symptoms of this condition include decreased body temperature, decreased breathing, low blood pressure, unresponsiveness or even coma. There are rare cases when myxedema can be fatal [3].
Hypothyroidism causes
This condition results when the thyroid gland fails to produce enough hormones. There are many factors which can cause hypothyroidism such as
- Treatment for hyperthyroidism: Those people who have hyperthyroidism (their thyroid gland produce too much thyroid hormone) are often treated with anti – thyroid medications or radioactive iodine to reduce and normalize their thyroid function. There are some cases when the treatment of hyperthyroidism can result in permanent hypothyroidism.
- Autoimmune disease: It is known fact that people who develop a particular inflammatory disorder called Hashimoto’s thyroiditis have the most common cause of hypothyroidism. Autoimmune disorders are happening when the immune system is producing antibodies that are attacking the own tissues. These antibodies are affecting the ability of thyroid gland to produce hormones. [4]
- Radiation therapy: We know that the radiation is used to treat cancers of the neck and head and it can affect the thyroid gland and it can lead to hypothyroidism. [5]
- Thyroid surgery: When you are removing all or a large portion of your thyroid gland, then it can diminish or halt hormone production. If this is your case, then you will need to take thyroid hormone for life. [6]
Risk factors: Every single person can develop hypothyroidism but you have increased risk of getting it if you:
- Have been pregnant or delivered a baby within past 6 months [7]
- Have had thyroid surgery (partial thryoidectomy) [6]
- Received radiation to your neck or upper chest [5]
- Have been treated with radioactive iodine or anti – thyroid medications
- Have other autoimmune diseases, such as rheumatoid arthritis or lupus, a chronic inflammatory condition [4]
- Have a family history of thyroid disease [8]
- Have an autoimmune disease [4]
- Are a woman older than age 60 [1]
References:
[1] Meng Z, Liu M, Zhang Q, et al. Gender and age impacts on the association between thyroid function and metabolic syndrome in Chinese. Medicine (Baltimore). 2015;94(50):e2193.
[2] Talaei A, Rafee N, Rafei F, Chehrei A. TSH cut off point based on depression in hypothyroid patients. BMC Psychiatry. 2017;17.
[3] Kelly JK, Butt JC. Fatal myxedema pericarditis in a Christian scientist. American Journal of Clinical Pathology. 1986;86(1):113-6.
[4] Saranac L, Zivanovic S, Bjelakovic B, et al. Why is the thyroid so prone to autoimmune disease? Hormone Research in Paediatrics. 2011;75:157–65.
[5] Inskip PD, Veiga LHS, Brenner AV, et al. Hypothyroidism after radiation therapy for childhood cancer: A report from the childhood cancer survivor study. Radiation Research. 2018;190(2):117-32.
[6] Tsai SH, Chien SC, Nguyen PA, et al. Incidences of hypothyroidism associated with surgical procedures for thyroid disorders: A nationwide population-based study. Frontiers in Pharmacology. 2019.
[7] Maraka S, Singh Ospina NM, O’Keeffe DT, et al. Subclinical hypothyroidism in pregnancy: A systematic review and meta-analysis. Thyroid. 2016;26(4):580–90.
[8] Manji N, Carr-Smith JD, Boelaert K, et al. Influences of age, gender, smoking, and family history on autoimmune thyroid disease phenotype. The Journal of Clinical Endocrinology & Metabolism. 2006;91(12):4873-80.
