Goiter is a general term for an enlarged thyroid gland that has the appearance of a swelling or fullness in the neck. Many persons with Hashimoto's thyroiditis have a goiter. Although the thyroid gland is usually painless, there can be some discomfort. At the extreme, large goiters can interfere with swallowing, breathing, or both. In many cases, goiters decrease in size, often considerably, after thyroid hormone replacement therapy is begun. Surgery is rarely required.
Nice To Know:
Before the connection of iodine and thyroid function was made, people realized that goiters (large thyroid gland seen as a swelling in the neck) were more common in certain areas-areas we recognize as low in iodine in the average diet. Indeed, the area around the Great Lakes was called the "Goiter Belt." The goiters in many people living there were not due to a problem within the thyroid such as Hashimoto's thyroiditis. Instead, the goiter developed because of the lack of iodine needed for the production of thyroid hormone.
The cells of the thyroid gland increased in size and number in response to long-term high levels of TSH, the hormone that stimulates the thyroid to produce thyroid hormone, working overtime in an effort to get the thyroid gland to produce adequate amounts of thyroid hormone, despite the low level of available iodine. This ability of the cells to adapt to chronically low levels of dietary iodine by enlargement and increase in function meant that many people retained low normal levels of thyroid hormone because their thyroid cells could take up and use virtually all of the iodine they consumed.
One of the major organs affected by thyroid hormone is the heart. Increased heart rate and palpitations are common in persons with untreated hyperthyroidism, and a slowed heart rate is common in persons with hypothyroidism.
Need To Know:
Persons who have hypothyroidism and heart disease should discuss their cardiac symptoms with their doctors before beginning thyroid hormone treatment.
Individuals having frequent attacks of angina, the heavy pain typically felt in the chest, jaw, or left arm, have symptoms indicating that their hearts are not receiving enough blood during the periods when angina is felt.
These individuals should plan the early phase of thyroid hormone therapy so that minimal stress is placed on the heart due to increased metabolic activity. This may be done by starting at a low dose of thyroid hormone, limiting exertion, or both.
If angina or other symptoms persist or worsen even on a low dose of thyroid hormone, other treatments may be required for the heart condition.
The decreased metabolic activity associated with hypothyroidism leads to increased blood levels of cholesterol. Individuals whose blood cholesterol levels are found to be high, particularly if they do not have a previous history of high cholesterol, may be advised to have thyroid hormone levels checked. If the high cholesterol is due (at least in part) to hypothyroidism, improvement will come after hormone treatment is begun. A low-fat, low-cholesterol diet will also help; if cholesterol levels remain high, appropriate drug therapy may be needed to lower them.
Anemia is the general term for any condition marked by a low red blood cell count. Because red blood cells carry oxygen between the lungs and the rest of the body, persons with anemia often feel tired with little exertion. This fatigue is in addition to the fatigue felt due to untreated hypothyroidism. Persons who have hypothyroidism, heart disease, and anemia become particularly tired and may develop angina or worsening of their angina.
Individuals with hypothyroidism may become anemic due to inadequate stimulation of red blood cell development in the bone marrow; this type of anemia (as well as persistent feelings of fatigue) usually goes away after thyroid hormone treatment is begun. Over-the-counter iron supplements and other preparations are not helpful.
However, if a premenopausal woman with untreated hypothyroidism has had heavy menstrual periods, she may have iron deficiency contributing to her anemic condition. These women will find iron supplementation useful in combination with their thyroid hormone treatment.
Hypothyroid persons with anemia, particularly elderly persons, should also be checked for possible pernicious anemia, an autoimmune form of anemia characterized by vitamin B12 deficiency. The same genes that cause a vulnerability to development of Hashimoto's thyroiditis can cause vulnerability to pernicious anemia, so it is particularly important to look for in anemic individuals who have a history of Hashimoto's thyroiditis.
Infertility is common in women whose thyroid hormone levels are low, and some women are diagnosed with hypothyroidism as part of a medical exam for infertility. After thyroid hormone treatment is begun, it is usually easier to conceive.
Because thyroid hormone crosses the placenta in small amounts, the thyroid hormone taken by the expectant mother may have important effects on the developing fetus.
Because the dose of thyroid hormone may need to be increased after a woman has conceived, it is valuable to get baseline (pre-pregnancy) thyroid tests (including TSH) and to periodically recheck during the pregnancy.
After delivery, the mother's thyroid hormone needs typically return to pre-pregnancy levels.
If You Are Having Surgery
It is generally better to schedule elective surgery for one to two months after beginning thyroid hormone treatment, because thyroid hormone levels will have come toward or into the normal range. The daily dose of thyroid hormone can be continued up to the time of surgery, although skipping a dose on the morning of surgery will not lead to problems.
On the other hand, if there is a pressing need for surgery it usually can be performed safely in an untreated or partially treated person with hypothyroidism.