Aging & Health A to Z
Causes & Symptoms
Common causes of hypothyroidism in later life include:
- Hashimoto’s disease, in which your immune system attacks and damages your thyroid gland. The reasons for this aren’t clear. Hashimoto’s disease is the most common cause of hypothyroidism in adults in the United States.
- Side effects of: earlier treatment for hyperthyroidism; surgery to remove much or all of the thyroid gland because of disease; or radiation treatment for neck or head cancer.
- Certain medications that can affect the thyroid gland
In older adults, hypothyroidism is often asymptomatic (it doesn’t cause noticeable symptoms) early on. If your healthcare professional thinks that you might have hypothyroidism, even though you don’t have noticeable symptoms, he or she can use blood tests to check.
If hypothyroidism isn’t treated, the symptoms get worse and more noticeable. You should contact your healthcare professional as soon as possible if you notice these common symptoms of the disease:
- Low energy levels and slowed thinking
- Weight gain
- Muscle weakness, aches, tenderness, or stiffness
- Pain, stiffness, or swelling in your joints
- Increased sensitivity to cold, or numbness
- Pale, dry skin, and brittle fingernails and hair
- Swelling in the face.
Hypothyroidism should be treated as soon as possible. Untreated, it can lead to other serious health problems such as goiter (enlargement of the thyroid gland) which may eventually make it difficult to swallow or breathe. Untreated hypothyroidism can also increase your risk of heart disease, an enlarged heart, and heart failure. Over time, it can damage your nerves and cause loss of muscle control as well.
Advanced untreated hypothyroidism can lead to a fatal complication known as “myxedema coma.” Warning signs of myxedema coma include: shallow breathing, unresponsiveness, below-normal body temperature, low blood pressure, and low blood-sugar levels. Call 911 for immediate emergency care if you or someone else has these symptoms.
The most common causes of hyperthyroidism in later life include:
- Graves' disease, an immune disorder that damages your thyroid gland, prompting it to produce too much thyroid hormone. This is the most common cause of hyperthyroidism in older adults in the United States.
- Non-cancerous or cancerous thyroid gland tumors.
- Non-cancerous or cancerous pituitary gland tumors.
- Other disorders that cause enlargement of the thyroid gland.
Symptoms of hyperthyroidism are often different in later adulthood than in earlier adulthood. In younger adults, hyperthyroidism typically causes such symptoms as hyperactivity and weight loss. The following symptoms are most common among older adults with hyperthyroidism:
- Abnormal heart rhythms (such as atrial fibrillation or a rapid heartbeat)
- Heart failure
- Muscle weakness and loss of muscle
- Difficulty tolerating heat and increased sweating
- Frequent bowel movements
- Graves’ opthalmopathy, a symptom of Grave’s disease in which the eyes begin to bulge outward. Graves ophthalmopathy is more common among older than younger adults with hyperthyroidism.
Older adults with the form of hyperthyroidism known as apathetic thyrotoxicosis often have the following symptoms:
- Depression and withdrawal
- Bone loss
- Inactivity and lack of energy
- Muscle weakness.
Thyroid nodules may be caused by:
- Ongoing or chronic inflammation of your thyroid gland due to Hashimoto's disease.
- Insufficient iodine in your diet. However, this is rare in the US, where iodized salt is added to many prepared foods.
Many thyroid nodules cause no obvious symptoms and most people don’t realize they have a nodule until their healthcare professional detects it during a routine check-up. Sometimes, though, a nodule can get big enough to be noticeable. Thyroid nodules may eventually get large enough for you to see, or to press on your throat so it is uncomfortable or difficult to breathe or swallow.
Some nodules increase the amount of triidothyronine hormone (T3) that your thyroid produces, causing symptoms of hyperthyroidism. A small percentage of thyroid nodules become cancerous.
Thyroid Cancer Risks
You have a higher than average risk of developing thyroid cancer if you:
- Are older than 60
- Have had radiation treatment – especially to the head or neck
- Have a family history of thyroid or other cancers affecting the body’s glands
- Have been exposed to radiation due to an accident
- Are male.
Updated: March 2012
Posted: March 2012