Rheumatoid arthritis (RA) and underactive thyroid (hypothyroidism) are different health conditions. However for many years, some experts suspect that both diseases are related. Unfortunately there is still no conclusive evidence to support this link. Interestingly, they are independently associated with the increased risk of cardiovascular diseases.
The term ‘hypo’ means ‘under’ describes deprivation, deficiency, or lower than normal level. And hypothyroidism is a condition of when the thyroid gland doesn’t work as usual as it should, especially when it fails to make adequate hormones.
There is also a condition called hyperthyroidism. As the name suggests, it is the opposite of hypothyroidism. Yap, it is overactive thyroid or when the thyroid gland produce too much thyroid hormones.
Normally, the size of your thyroid gland is about the size of your 2 thumbs in the shape of ‘V’. Although it is small in size, but it is so important to support some body functions!
T4 (thyroxine ) and T3 (tri-iodothyronine) are hormones produced by thyroid gland. These hormones are important to help maintain the metabolic process of the body, including energy expenditure and growth! They are also essential to help regulate the body temperature and the productions of some proteins. Even it can affect rate of your heart beats, too.
If the thyroid gland works greater than normal (over-active), you can have weight loss easier! On the other hand, if it works lower than normal (under-active), you can have weight gain easier.
Unexplained weight gain is not the only one. Fatigue can be another common symptom of hypothyroidism at early stage.
The following symptoms may also occur as your thyroid produce lower hormones and your metabolic rate continues to slow: dry skin, constipation, more sensitive to cold, muscle weakness, thinning hair, heavier menstrual bleeding, increased cholesterol, impaired memory, or even slowed heart rate.
The signs and symptoms can vary, depending on how low of hormone deficiency that you have. But generally, they are more likely to develop and progress slowly. Even sometimes you may consider them as a part of aging.
In addition, when your thyroid is inefficient in producing hormones, it can enlarge and over time it could be inflamed. This is the reason of why people with hypothyroidism can have a condition called goiter, enlarged /swollen thyroid gland.
In hypothyroidism, there are numerous of different causes.
But many times, it is related to the existence of Hashimoto’s disease, an autoimmune disorder that can mistakenly attack cells /tissues of thyroid gland and eventually can affect the ability of the thyroid gland to make hormones.
Another possible cause is iodine deficiency. Your thyroid needs plenty of iodine to keep functioning as well.
Your body needs dietary iodine by about 150 millionths of a gram (mcg) per day to make enough thyroid hormones. Iodine can be found in iodized salt, seafood, or some plants (especially for plants that grow in iodine-rich soil).
Other possible triggers of developing hypothyroidism:
- Side effects of using certain medications. These may include too much taking medications for hyperthyroidism, radiation therapy for cancer, thyroid surgery, or lithium-medicine (typically used to help treat some psychiatric disorders).
- Dysfunction in pituitary gland, a tiny organ found at the base of your brain. If something goes awry with pituitary gland, there will be not enough thyroid-stimulating hormone to stimulate the thyroid to make T4 and T3.
- Problems in hypothalamus, another essential part of the brain. Together, both hypothalamus and pituitary gland regulate the function of the thyroid gland.
- Having abnormality function of thyroid at birth. Even in rare cases, a few babies don’t have thyroid gland at birth.
- Pregnancy! A few pregnant women experience hypothyroidism during pregnancy or after giving birth. Hypothyroidism related to pregnancy may occur due to the immune system makes antibodies to its own thyroid gland.
Untreated under-active thyroid could lead to numerous complications. These include:
- Cardiovascular diseases. Poorly-controlled hypothyroidism can increase the risk of high blood cholesterol, enlarged heart, or even a heart failure.
- As mentioned before, thyroid gland can enlarge to boost its performance in producing adequate thyroid hormone. Over time, this constant stimulation may lead to enlarged thyroid or goiter. This enlargement can be visible and may affect your appearance. It may also cause problem in swallowing or even breathing.
- In rare cases, the disease could cause a life-threatening condition called myxedema. It is usually characterized by intense cold intolerance & drowsiness that typically come with a significant lethargy or even unconsciousness. It could be a consequence of long-term, undiagnosed under-active thyroid.
- Hypothyroidism could pose the risk of causing damage to peripheral nerves, too. Numbness, tingling, or even pain usually occur in the area of where the nerves damage occurs (such as legs or arms).
- Other possible complications include ovulation problem that may affect fertility, the risk of birth defect in babies born from mother with untreated thyroid disease, and psychological problems (such as depression).
If compared to other kinds of arthritis, RA is relatively more difficult to understand. Though it’s clearly that this joint disease is related the abnormality immune system, but no one knows exactly why and how this abnormality happens.
In RA, antibodies can be harmful for some healthy tissues in the joint. They are formed against tissue surrounding joint called synovium. This eventually leads to inflammation in or/and around the involved joint.
RA is also a chronic autoimmune disorder. It may go away for several weeks or even months and then it can return.
And unfortunately, each flare could lead to joint damage. The more flares you have, the greater risk of joint damage.
Therefore, modern treatments for RA are now intended to make the disease go into remission – though there is still no cure for the disease.
RA is categorized into group of systemic conditions. This means that it could pose the risk of widespread inflammation, causing complications that even have nothing to do with the joint such as heart problems, high blood pressure, or even eye problems – learn more the complications in this section!
In some cases, under-active thyroid could contribute to problems of joint and muscles – specifically, these include: