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Hypothyroidism
Hypothyroidism is a medical condition of the thyroid gland in which it is not able to produce enough thyroid hormones, primarily thyroxine (T4) and Triiodothyronine (T3), for the needs of the whole body. These hormones control many metabolic activities of the human body, either directly or indirectly, such as breathing, weight, digestion, growth, moods, etc.
1.0What is the Thyroid Gland?
The thyroid gland is a specific type of endocrine gland that is small butterfly-shaped. It is divided into two lobes that are connected by a thick strip of tissue known as the isthmus. It is located on the lower front side of the neck, which is just below Adam's apple. The Thyroid Gland is very important in regulating metabolic rate (the speed of cells by which they convert food into energy) and maintaining several important physiological functions such as growth and development, temperature regulations, heart rate, etc., through the production of thyroid hormones.
The most important factor for producing these hormones is Iodine. Iodine deficiency in the diet leads to conditions such as Goitre (enlargement of the thyroid gland) and Hypothyroidism (inability to produce thyroid hormones).
2.0Hypothyroidism Causes
The causes of Hypothyroidism depend from person to person. Some of the most common causes are:
- Autoimmune (Hashimoto's Thyroiditis): This is the most common cause of hypothyroidism. Autoimmunity is a medical condition in which the body’s immune system starts to mistakenly attack its own cells or tissues rather than foreign invaders. The most common autoimmune disease that leads to Hypothyroidism is Hashimoto’s Thyroiditis.
- Iodine deficiency: Iodine is a key factor in producing thyroid hormones (T3 and T4). Lack of iodine in the diet leads to Hypothyroidism.
- Thyroid Surgery or Radiation Therapy: Removal of thyroid tissue totally or partially or radiation treatments due to conditions like Thyroid cancer, a large goitre, etc, also leads to T3 and T4 deficiency.
- Medications: Certain drugs, such as lithium, can also interfere with thyroid function.
- Pituitary or Hypothalamic Disorders: The pituitary gland, along with the Hypothalamus gland, works in close association with the Thyroid gland, also known as The Hypothalamic-Pituitary-Thyroid (HPT) Axis.
The Pituitary gland produces thyroid-stimulating Hormone which gives signals to the thyroid to produce thyroid hormones. Dysfunction in the pituitary gland, leading to decreased release of (TSH), results in thyroid impairment.
The same is the case with the Hypothalamus which releases thyrotropin-releasing hormone (TRH), which stimulates the pituitary to produce TSH. Hence, Damage or any dysfunction of the Hypothalamus also leads to Hypothyroidism.
- Congenital Hypothyroidism: Some babies are born with less or no developmental thyroid gland in the body.
3.0Hypothyroidism Symptoms
The signs of hypothyroidism develop and propagate with varying degrees. Common signs include:
- Fatigue & Weakness: Due to slow metabolism.
- Weight gain: Often for no apparent reason, as energy is burned much more slowly.
- Cold intolerance: A sensitivity to cold temperatures because heat production in the body is reduced.
- Dry Skin and Dry Hair: Dryness and thinning of the skin and brittle hair are common.
- Constipation: A slowed digestive system will cause constipation.
- Depression: Hormonal imbalance leads to depression.
- Bradycardia: The heart will beat slowly as metabolic activities are low.
- Goitre: Swelling in the neck where the thyroid gland is located. The swelling usually arises from an elevated TSH.
- Muscle Cramps and Joints Pain: Slowed metabolism causes aches and pains in the muscles and joints.
4.0Hypothyroidism Diagnosis and Treatment:
Hypothyroidism Diagnosis
For confirmation of Hypothyroidism, mainly two types of diagnosis are done. These are:
- Blood Tests: In blood tests, levels of TSH, T3, and T4 are observed. Generally, in Hypothyroidism, TSH levels are elevated, while T3 and T4 levels remain low.
- Ultrasound or Biopsy: Imaging tests are done if there is a goiter or thyroid nodule, which helps in confirmation as well as assessing the condition of the thyroid gland.
Hypothyroidism Treatment
Hormone replacement therapy is used as the primary treatment for Hypothyroidism. In this therapy, synthetic hormones that our body is unable to produce are injected into the body. It involves:
- Levothyroxine: It is the most common hypothyroidism medication. Levothyroxine is a synthetic T4 or thyroxine that is used for the normalisation of thyroid hormone in the body.
- Dose adjustments: The dose of levothyroxine is adjusted based on blood tests and how a patient has responded to treatment.
- Regular monitoring: A patient's blood should be periodically checked to monitor the levels of thyroid hormones to ensure they remain within the normal range and adjust medications appropriately.
- Iodine Supplementation: If iodine deficiency is the cause of Hypothyroidism, then in this case supplement Iodine is recommended to the patients.