Hi XXXXXXX,

Thanks for writing in.
I am a medical specialist with an additional degree in cardiologist.
To answer your question in one line will be all Hashimoto's Thryroiditis have hypothyroidism. But all hypothyroid disease patients are not due to Hashimoto's Disease.
Coming to:
Hypothyroidism
Hypothyroidism is a condition in which the body lacks sufficient thyroid hormone. Since the main purpose of thyroid hormone is to "run the body's metabolism XXXXXXX it is understandable that people with this condition will have symptoms associated with a slow metabolism. The estimates vary, but approximately 10 million Americans have this common medical condition. In fact, as many as 10% of women may have some degree of thyroid hormone deficiency. Hypothyroidism is more common than you would believe, and millions of people are currently hypothyroid and don't know it. For an overview of how thyroid hormone is produced and how its production is regulated, check out our thyroid hormone production page.

Causes of Hypothyroidism
1. The first is a result of previous (or currently ongoing) inflammation of the thyroid
gland, which leaves a large percentage of the cells of the thyroid damaged (or
dead) and incapable of producing sufficient hormone. The most common cause
of thyroid gland failure is called autoimmune thyroiditis (also called Hashimoto's
thyroiditis), a form of thyroid inflammation caused by the patient's own immune
system.

2. The second major cause is the broad category of "medical treatments XXXXXXX The
treatment of many thyroid conditions warrants surgical removal of a portion or
all of the thyroid gland. If the total mass of thyroid producing cells left within
the body are not enough to XXXXXXX the needs of the body, the patient will
develop hypothyroidism.

Coming to Hashimoto's Disease:
Hashimoto's disease is a disorder that affects your thyroid. The thyroid gland is part of your endocrine system, which produces hormones that coordinate many of your body's activities.

In Hashimoto's disease, also known as chronic lymphocytic thyroiditis, body's immune system attacks one's thyroid gland. The resulting inflammation often leads to an underactive thyroid gland (hypothyroidism). Hashimoto's disease is the most common cause of hypothyroidism in the United States. It primarily affects middle-aged women, but also can occur in men and women of any age.

Treatment of Hashimoto's disease with thyroid hormone replacement usually is simple and effective.

To determine the right dosage of levothyroxine initially, doctor generally checks the level of TSH after a few weeks of treatment. Excessive amounts of the hormone can accelerate bone loss, which may make osteoporosis worse or add to your risk of this disease. Overtreatment with levothyroxine also can cause heart rhythm disorders (arrhythmias).

If someone has coronary artery disease and severe hypothyroidism, the doctor may start treatment with a smaller amount of medication and gradually increase the dosage. Progressive hormone replacement allows the one's heart to adjust to the increase in metabolism.

Levothyroxine causes virtually no side effects when used in the appropriate dose and is relatively inexpensive. If you change brands, let your doctor know to ensure you're still receiving the right dosage. Also, don't skip doses or stop taking the drug because you're feeling better. If you do, signs and symptoms will gradually return.

Effects of other substances
Certain medications, supplements and even some foods may affect your ability to absorb levothyroxine. One should inform doctor if he/she eats large amounts of soy products or a high-fiber diet, or if he/she takes any of the following:

Iron supplements, including multivitamins that contain iron
Cholestyramine (Questran), a medication used to lower blood cholesterol levels
Aluminum hydroxide, which is found in some antacids
Sodium polystyrene sulfonate (Kayexalate), to prevent high blood potassium levels
Sucralfate, an ulcer medication
Calcium supplements

Than dose administration can be tailored to these medicines intake.

I hope I have answered your question you may close it with comments. If you have any supplementary question to ask, I will be only too happy to answer.
Best Wishes

Dr Anil Grover
MBBS, MD (Medicine) DM (Cardiology)

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