<<Disclaimer: Verify this information before applying it to your situation.>> Thyroid Disease: Why Do Celiacs Have It?<2> ------------------------------------------- by Dr. Patricia Daly (Dr. Daly is an endocrinologist at Harvard Medical School. She gave a presentation at the CSA annual conference held October 1998 at Warwick, Rhode Island. What follows are highlights of her talk, as recorded by Janet Rinehart.) There is a relationship between thyroid disease and celiac disease (CD). Thyroid disease and abnormal thyroid tests are more common in people with CD than in the general population. At the same time CD is more common in individuals who have thyroid disease. This association appears to be based on the tendency for people with autoimmune diseases to be predisposed to other autoimmune diseases. The term autoimmune refers to diseases in which the immune system of the body makes antibodies (normally made to attack foreign substances like viruses) against some part of the body. Celiac disease is an autoimmune condition; likewise a number of thyroid diseases are autoimmune conditions: * Antibodies that stimulate the thyroid gland (causing an overactive thyroid condition, or Graves Disease) * Antibodies that block the effect of the thyroid (causing an underactive thyroid condition, or hypothyroidism) * Antibodies relating to autoimmune destruction of the thyroid, or Hashimoto's thyroid disease. (This condition can result in an underactive thyroid, and also can lead to enlargement of the thyroid or the formation of nodules in the thyroid gland.) Research articles support evidence that there is a connection between CD and thyroid disease: 1. JCI 1972; *Lancet* 1976; Gut 1983: Graves disease patients have a higher than usual proportion of HLA DR3 antigens. 2. 1994, *European Journal of Endocrinology*: 5% of patients with autoimmune thyroid disease had sprue. 3. 1995, *Endocrinology Practice*: a case study report of increased dose requirements of thyroid hormone (because of malabsorption) leading to diagnosis of sprue. 4. 1997, *British Journal of Dermatology*: 4.3% of UK and 6% of sprue patients had autoimmune thyroid disease. Since we now know of the link between CD and thyroid disease, what can you and your physician look for to determine if you might have thyroid disease in addition to CD? The thyroid gland, located at the base of your Adam's apple in your throat, is important in regulating metabolism. This gland affects every system of the body including the brain, heart, liver, kidney, pancreas, reproduction system, etc. When you don't have enough thyroid hormone, everything tends to slow down. When you have an overactive thyroid, things speed up. The heart beats faster, you breathe faster, you lose weight, bowels move faster, etc., but you feel more tired because more energy is being expended. Hypothyroidism -------------- Hypothyroidism is 4-8 times more common in women. It is more likely when there is a family history of autoimmune disease. It affects 10-20% of women over age 50 in the general population. It is more common in the elderly, and is often wrongly attributed to menopause and aging. Hypothyroidism affects all cells in the body and the symptoms tend to worsen over time. Symptoms include: Thyroid enlargement Constipation Weight gain Brittle nails Bradycardia (slowing of heart rate) Hypertension (increase in blood pressure) Psychiatric abnormalities, such as depression Cold intolerance Fatigue Coarse hair Dry, scaly skin Menstrual irregularities Infertility Elevated cholesterol Thyroid disease can contribute to menstrual disorders, particularly heavier periods. Infertility is common in untreated hypothyroidism, and pregnancy management is an important issue if one has thyroid disease Treatment of hypothyroidism consists of replacement therapy. Treatment choices include desiccated thyroid or Levothyroxine. Desiccated Thyroid is made from desiccated (dried and pulverized) pig thyroids. The amount of thyroid hormone can vary greatly from batch to batch. Levothyroxine (Synthroid, Levoxyl, Levothroid, and other brands ) is synthesized in the laboratory. It contains a fixed amount of Levothyroxine (T4). This is one of the hormones your thyroid gland makes. Using Levothyroxine tends to be more accurate than with dessicated thyroid. Side effects of over-treatment (getting too much thyroid hormone) include an increased risk of osteoporosis and an increased risk of an irregular heart rhythm, known as atrial fibrillation. For best absorption, Levothyroxine should best be taken on an empty stomach, one-half to one hour before eating, or 2 hours afterwards. Don't take iron supplements (or vitamins containing iron) at the same time. Because absorption can vary, once you start on one brand, it is best to stay with it. Or if you switch, blood tests can be taken to see if levels are still in range (6-8 weeks after change). Hyperthyroidism --------------- Graves Disease is a condition in which the body makes antibodies that "trick" the thyroid into thinking it needs to continue making excessive amounts of thyroid hormone. Graves Disease can sometimes result in hypothyroidism due to thyroid destructive therapies or the natural history of the disease itself.. Common symptoms of Graves Disease include: Weight loss, but with increased appetite Hyperpigmentation (darkening of the skin) Pretibial myxedemia (rare) Enlarged thyroid (goiter) Emotional instability--irritability and moodiness Shortness of breath with exertion Contributes to congestive heart failure Increased frequency of bowel movements Osteoporosis--thinning of the bones Myopathy--weakness of proximal muscles (near shoulders and thighs) Heat intolerance, sweaty Warm, smooth skin Plummer's nails Hives Eye signs - deteriorations Racing heart beat Changes in periods, fewer, lighter Tremors Insomnia The best laboratory test to diagnose an overactive thyroid is the TSH (thyroid stimulation hormone). The normal range is usually 0.5 to 5. A low value would suggest you need more tests to confirm that your thyroid is underactive. Hyperthyroidism can be treated in several ways, including antithyroid agents, radioactive iodine, surgery, and iodine (temporary measure only). If you are diagnosed with hyperthyroidism, ask your doctor to refer you to a board-certified endocrinologist to help you determine which treatment is best for you. Implication between the Association of CD and Thyroid Disease ------------------------------------------------------------- You and your doctor should have a lower threshold for testing for thyroid disease in people with CD. If you have CD and an underactive thyroid, you need to be concerned about thyroid hormone absorption. If your CD is not adequately treated (resulting in malabsorption), you will not absorb all of your thyroid hormone and your thyroid condition will worsen. With regard to an overactive thyroid, the symptoms may be confusing and may mimic CD (particularly with increased bowel movements and weight loss).