The thyroid gland is a butterfly-shaped organ that sits in front of our neck. It is an endocrine gland, meaning it secretes hormones. These thyroid hormones are important for our normal cell function.
Sometimes, thyroid diseases occur when the gland secretes either too much or too little hormones.
When it secretes too much hormone, it is termed hyperthyroidism. If too little, it is termed hypothyroidism.
Often, a disease of the thyroid is accompanied by enlargement of the gland. This is termed “goitre”. Let us go through some of them.
Hyperthyroidism
One of the most common causes of hyperthyroidism is called Grave’s disease. In this disease, the body produces antibodies that cause the thyroid gland to increase hormone production and secretion.
The symptoms experienced by patients are usually due to increased cell activity. Here are some examples:
Sensitivity to heat
An increase in body metabolism can lead to a rise in body heat production. A person may feel warm even though they are in an air-conditioned room!
Irritability and nervousness
Hyperthyroidism can affect the mood of a person in a certain way. These changes are brought about due to the acceleration of body processes.
Irregular or fast heart rate (palpitations)
Thyroid hormones can cause the heart to beat faster and harder. This can also lead to difficulty exercising as the heart beats irregularly at fast heart rates.
Irritability and nervousness
Hyperthyroidism can affect the mood of a person in a certain way. These changes are brought about due to the acceleration of body processes.
Weight loss
With increased cellular activity in hyperthyroidism, the body will have a higher basal metabolic rate (BMR). This is the energy that the body uses while at rest. With a higher BMR, more energy is used up and can lead to weight loss.
Menstrual abnormalities
Hyperthyroidism can lead to irregular periods. This is because the excess in thyroid hormones can also affect the levels of other hormones that control the menstrual cycle.
Diarrhea
A person with hyperthyroidism may notice that they have more frequent bowel movements. Thyroid hormones may lead to overactivity of our nervous system which regulates our bowel movements, leading to the development of this symptom.
Hypothyroidism
The most common cause of hypothyroidism is called Hashimoto’s thyroiditis. It is an autoimmune disorder where the immune system produces antibodies that attack its tissues. In Hashimoto’s thyroiditis, these antibodies target and damage the thyroid gland. This leads to decreased ability of the gland to produce and secrete thyroid hormones.
The symptoms experienced are a result of a slowing down of the body’s metabolic processes. Here are some examples:
Brain fog
Thyroid hormones play a role in our ability to concentrate. A lack of it can affect our memory and lead to difficulty in functioning optimally at work or school.
Weight gain
Those with hypothyroidism are unable to burn off as many calories compared to their peers without the condition. This is because of the slowing down of the body’s metabolism.
Menstrual abnormalities
As with hyperthyroidism, a decrease in thyroid hormones can also disrupt the normal menstrual cycle. Individuals may experience irregular or heavy periods.
Sensitivity to cold
Due to a slowing down of the body’s metabolic processes, individuals with hypothyroidism produce less body heat. This leads to a person feeling unusually cold even though the weather is not.
Constipation
Individuals with hypothyroidism may experience decreased bowel movements from reduced activity of the gut. This causes stool to move slower through the gut.
Carpal tunnel syndrome
This condition occurs when the median nerve which supplies our hand muscles gets compressed near the wrist. Interestingly, hypothyroidism may cause some deposits to form on the nerve, contributing to its compression.
How do we diagnose thyroid problems?
Blood test – If you have symptoms of thyroid diseases, a blood test will be done as a screening tool. Blood levels of Thyroid-stimulating hormone (TSH) will be measured as it reflects the activity level of the thyroid gland. Low levels of TSH indicate hyperthyroidism while the converse suggests hypothyroidism.
Thyroid antibody test – The most common causes of hyper and hypothyroidism occur due to the body producing antibodies that damage the thyroid. Therefore, specific antibodies can be measured in the blood, which can help clue us to the cause of the thyroid problem.
Radioactive iodine uptake test – Normally, the thyroid gland takes up iodine from the blood which plays a role in making thyroid hormones. In this test, you will be given some radioactive iodine to swallow. It will be absorbed by the thyroid gland.
The amount of iodine taken up reflects the activity of the thyroid gland. In hyperthyroidism, there will be more iodine uptake as there is an increase in the production of hormones.
Consequently, it will be less in hypothyroidism. This test will show us whether the thyroid is overactive, underactive, or functioning normally.
How are thyroid problems treated?
Hyperthyroidism is commonly treated with drugs that block the production of thyroid hormones.
An example of a medication, propylthiouracil, a thioamide. However, this drug will take up to 2 months to take effect. Doctors will prescribe propranolol which can block the thyroid hormone effects for this period.
Surgery may be considered if the individual does not respond to medical treatment or has a severely enlarged thyroid gland. In thyroid surgery, all or part of the gland is removed in an attempt to reduce thyroid hormone levels.
If the entire gland is removed, patients will have to take the same medication as those with hypothyroidism for life.
Hypothyroidism can be treated by giving medicines that can replace the thyroid hormones. A commonly used medicine is levothyroxine. Hypothyroidism is a lifelong condition, so this medicine will have to be taken for life.
In conclusion, many symptoms can occur as a result of thyroid diseases. If you suspect that you may have symptoms of a thyroid problem, do consult your doctor for advice.
References:
- https://www.btf-thyroid.org/what-is-thyroid-disorder
- https://www.moh.gov.my/moh/resources/Penerbitan/CPG/Endocrine/CPG_Management_of_Thyroid_Disorders.pdf
- https://www.nhs.uk/conditions/underactive-thyroid-hypothyroidism/symptoms/
- https://www.nhs.uk/conditions/overactive-thyroid-hyperthyroidism/treatment/
