Hypothyroidism: What it is, Causes, Treatment & More

What is Hypothyroidism?

Hypothyroidism, also known as underactive thyroid, is a condition in which the thyroid gland does not produce or release enough hormones to fulfil the bodys needs. Due to low hormone levels, the body's metabolism slows down, leading to fatigue and weight gain.

This condition can be difficult to diagnose, as symptoms are often not noticeable in the early stages and are similar to those of many other diseases. However, once diagnosed, hypothyroidism can be managed with hormone replacement therapy, and you can continue to live a normal and healthy life.

What are the Types of Hypothyroidism?

Hypothyroidism can be classified into four main types, each with its own cause and origin point in the hormone chain.

How Common is Hypothyroidism in India?

India has about 42 million adults with various thyroid disorders, including hypothyroidism. It is the most common thyroid condition, affecting nearly 1 in 10 adults in the country. Most of these affected adults are women, as they are eight times more likely to be affected than men.

The prevalence of hypothyroidism is 11% in India, while in Western countries, it is just 2% to 4.6%. States located along the country's coast have a higher prevalence rate than inland states. Due to many factors, like lack of awareness and ignorance of symptoms, almost one-third of the hypothyroidism cases in India are undiagnosed and untreated.

What are the Symptoms of Hypothyroidism?

It is worth noting that the symptoms of hypothyroidism tend to develop slowly over time, often over years, and may be mistaken for symptoms of other illnesses. The symptoms do not vary much across various types of the disease, so here are the common signs of an underactive thyroid:

• Extreme tiredness and fatigue

• Unexplained weight gain

• Inability to tolerate cold temperatures

• Brain fog, such as forgetfulness or difficulty concentrating

• Low mood, depression, or anxiety

• Dry, coarse skin and hair, or hair loss

• Painful or weak muscles and joints

• Numbness or tingling in the hands

• Slow heart rate

• Elevated blood cholesterol levels

• Hoarseness or a croaky voice

• Frequent, heavy, or irregular menstrual periods

• Changes in fertility or the menstrual cycle

• Puffiness around the eyes or drooping eyelids

• Constipation

What Causes Hypothyroidism?

Hypothyroidism can develop due to a range of conditions and factors, some present from birth and others developing over time. Let's look at the most common causes:

• Hashimoto's Disease: The most common cause of hypothyroidism, this is an autoimmune condition where the immune system mistakenly attacks the thyroid gland, leaving it unable to produce enough hormones. It is most common in women and usually develops between the ages of 30 and 50.

• Thyroiditis: Inflammation of the thyroid can cause stored hormones to leak into the bloodstream. While this may initially cause hormone levels to spike, it can eventually lead to an underactive thyroid. It can occur after a viral illness or pregnancy or as a painless autoimmune condition.

• Congenital Hypothyroidism: Some babies are born with a thyroid that is underdeveloped or does not function properly. If left untreated, it can lead to growth failure and intellectual disability, which is why newborn screening is important.

• Surgical Removal of the Thyroid: If part of the thyroid is removed, the remaining portion may still produce adequate hormones. However, removing the entire thyroid always results in hypothyroidism, requiring lifelong hormone replacement.

• Radiation Treatment: Radiation therapy around the neck or thyroid, or treatment for an overactive thyroid using radioactive iodine, can damage thyroid cells and reduce hormone production over time.

• Iodine Deficiency: The thyroid needs iodine to produce hormones. A lack of sufficient dietary iodine can impair thyroid function.

• Pituitary Gland Disorders: Since the pituitary gland signals the thyroid to produce hormones, the disorders of the pituitary gland, including noncancerous tumours, can lead to hypothyroidism.

• Certain Medications: Some medicines, including lithium, amiodarone, and thalidomide, can interfere with thyroid hormone production as a side effect.

Risk Factors of Hypothyroidism

While hypothyroidism can affect anyone, certain factors make you more likely to develop the condition. These include:

• Gender: Women are significantly more likely to develop hypothyroidism than men.

• Family History: Having a parent or sibling with a thyroid condition or autoimmune disease increases your risk.

• Autoimmune Conditions: Having an autoimmune disease such as type 1 diabetes or coeliac disease, raises the likelihood of developing hypothyroidism.

• Previous Thyroid Treatment: If you have been treated for hyperthyroidism or have had thyroid surgery in the past, you are at a higher risk.

• Radiation Therapy: Having received radiation treatment to the neck, upper chest, or head can damage the thyroid and affect its ability to function properly.

• Pregnancy: Pregnancy can trigger thyroid changes in some women, increasing the risk of developing hypothyroidism during or after pregnancy.

• Certain Medications: Starting or stopping certain medicines that affect thyroid function can also increase your risk.

What are the Complications of Hypothyroidism?

With proper treatment, complications of hypothyroidism are infrequent. However, if left untreated for a long time, the condition can lead to a host of serious health problems, including:

• Goitre: Hypothyroidism can cause the thyroid gland to enlarge, a condition known as a goitre. In severe cases, a large goitre can make swallowing or breathing difficult.

• Heart Problems: An underactive thyroid can lead to elevated LDL or 'bad' cholesterol levels, increasing the risk of heart disease and heart failure.

• Peripheral Neuropathy: Long-term untreated hypothyroidism can damage the peripheral nerves, causing pain, numbness, and tingling in the arms and legs.

• Infertility: Low thyroid hormone levels can interfere with ovulation, making it harder to conceive. Some autoimmune conditions that cause hypothyroidism can also independently affect fertility.

• Birth Defects: Babies born to mothers with untreated hypothyroidism may have a higher risk of birth defects and developmental problems. However, if the condition is identified and treated early in life, the chances of healthy development are excellent.

• Myxedema Coma: Myxedema coma is a rare but life-threatening complication caused by extremely low thyroid levels. It causes disorientation, unconsciousness, slow breathing, and low blood pressure. In fact, it is a medical emergency where you should get hospitalised immediately.

When Should I See My Healthcare Provider?

If you notice symptoms such as unexplained weight gain, dry skin, or persistent fatigue, it is worth bringing them to your healthcare provider's attention. They may run tests to rule out hypothyroidism or other underlying conditions. If you are already on medication for hypothyroidism and your symptoms return or do not improve, inform your doctor, as your dosage may need to be adjusted.

Seek emergency medical attention immediately if you experience any of the following, as they may indicate myxedema, a potentially life-threatening condition:

• Difficulty breathing

• Extreme lethargy or unresponsiveness

• Abnormally low body temperature

• Low blood pressure

• A very slow heartbeat

How is Hypothyroidism Diagnosed?

Diagnosing hypothyroidism involves a combination of physical examination and blood tests, as its symptoms can easily be mistaken for those of other conditions. Here is how the process typically works.

How is Hypothyroidism Treated?

Hormone replacement therapy is used by most doctors to treat hypothyroidism. If you have been diagnosed with subclinical hypothyroidism, treatment may not always be necessary. Here's how the condition is treated:

Can Hypothyroidism be Prevented?

In most cases, hypothyroidism cannot be prevented. However, there is one exception worth noting. If your hypothyroidism is caused by iodine deficiency, it can be prevented by ensuring you get enough iodine through your diet.

Here are some ways to do that:

• Include iodine-rich foods in your daily diet such as milk, dairy products, eggs, and saltwater fish.

• Use iodised table salt as a simple and effective way to maintain adequate iodine levels.

• Some dietary supplements also contain iodine, but avoid taking them in excess.

• WHO recommends 90 mcg of iodine daily for young children (0 to 5 years) and 120 mcg daily for children between 6 to 12 years. Those aged 12 and older are recommended to take 150 mcg per day. A higher intake of 250 mcg daily is advised for pregnant and lactating women.

For all other types of hypothyroidism, early diagnosis and prompt treatment are the best ways to reduce the risk of complications and maintain a good quality of life. If you notice any symptoms, speak to your healthcare provider as soon as possible.

What is the Prognosis of Hypothyroidism?

With the right treatment and regular care, most people with hypothyroidism do very well. There is no cure yet, but daily hormone replacement therapy works well, and most people can live a normal, healthy life. Once you are diagnosed, you will need to take medicine every day to keep your thyroid hormone levels in a healthy range.

In general, people who are treated have a very good prognosis. But hypothyroidism untreated, can lead to serious complications, including myxedema coma, which can be fatal, so it is important to diagnose and treat this condition early and consistently.

Hypothyroidism During Pregnancy

Hypothyroidism can cause fertility issues and an increased risk of complications in pregnancy. But with regular thyroid function tests and prompt medication, these risks can be greatly reduced. If you have hypothyroidism and are planning a baby, it is best to treat the condition before you become pregnant.During pregnancy, the recommended treatment is thyroid hormone replacement therapy, and the dose will likely need to be adjusted as the pregnancy progresses. Regular monitoring of thyroid levels is recommended, and thyroid medication should not be taken at the same time as prenatal vitamins because the minerals may interfere with absorption.

Does Health Insurance Cover Hypothyroidism?

Most health insurance plans in India cover hypothyroidism, but the extent of coverage can differ from one insurer to another. Depending on your policy, you may be covered for hospitalisation, OPD consultations, and pharmacy expenses.

However, if you have hypothyroidism at the time of policy purchase, it will most likely be classified as a pre-existing disease or PED. In those cases, a waiting period of 2 to 4 years is applicable before you can make claims associated with the condition. Therefore, it is wise to read the policy documents carefully and ask your insurer to clarify coverage details before you buy.

How Much Health Insurance is Needed for Hypothyroidism Treatment?

The cost and duration of treatment for hypothyroidism can differ, based on how serious the disease is. But in most cases, long-term treatment is required. One should have health insurance coverage of about ₹5 lakh to ₹10 lakh to manage medical expenses.

For senior citizens or people with other health complications, a coverage amount of ₹15 lakh to ₹20 lakh is generally recommended for better financial protection.