Subclinical or overt hypothyroidism – what is the difference? The dictionary defines ‘Overt’ as being “undisguised, unconcealed, plain to see, plainly visible etc”. Therefore by inference overt hypothyroidism is hypothyroidism that is clearly evident. The symptoms will be very noticeable and the patient will be very obviously suffering from an underactive thyroid. Diagnostically, according to the Endocrine Society someone will be diagnosed with overt hypothyroidism when they present with raised serum TSH levels and low-serum free T4 levels.
Subclinical hypothyroidism is typically described as having ‘mild thyroid failure’ with an elevated level of serum TSH and normal levels of serum free T4 (Endocrine Society). This is also the most prevalent type of thyroid disorder. Studies indicate it affects between 3 and 15% of adults. However some sources believe it could be much higher and that it is one of the most under diagnosed medical conditions. Treating subclinical hypothyroidism is also a somewhat contentious issue, although it’s generally agreed that pregnant women, and those intending to get pregnant, should always be treated. Some cases of subclinical hypothyroidism do progress to overt hypothyroidism.
Overt hypothyroidism therefore is an underactive thyroid condition that has progressed to the stage of producing noticeable and recognizable symptoms of an underactive thyroid and this is confirmed by testing. It’s also the stage at which treatment becomes non-negotiable. If treatment isn’t started the disease will progress with an accompanying deterioration in the patient’s overall health and well-being.
Interesting Questions about Thyroid:
If you or a blood relative has Hashimoto’s thyroiditis or Graves’ disease, there is a chance that your children will inherit the problem. These diseases are also linked to other autoimmune conditions, such as premature gray hair, diabetes mellitus, arthritis, and patchy loss of skin pigment (vitiligo). You should tell your child’s doctor, so that the appropriate examinations can be performed.
Also, one out of every 4,000 infants is born without a working thyroid gland. If the problem is not corrected, the child will become mentally and physically retarded. Therefore, all newborns in the United States are tested for the disease. Once the problem is discovered and corrected, the child can grow up normally.
When are thyroid hormone pills used?
Thyroid hormone pills provide the body with the right amount of thyroid hormone when the gland is not able to produce enough by itself. The pills are frequently needed after surgery or radioactive iodine therapy.
Thyroid hormone tablets are the standard treatment for hypothyroidism. While symptoms usually get better within a few months, most patients must take the pills for the rest of their lives. This is especially true for hypothyroidism caused by Hashimoto’s thyroiditis or radioactive iodine treatment.
If the entire thyroid gland has been surgically removed, thyroid hormone tablets replace the body’s own source of the hormone. If only a part of the gland has been removed, the pills may keep the remaining gland from working too hard. This decreases the chance that the thyroid gland will grow back.
How much hormone do I need?
The preferred hormone for treatment is levothyroxine (T4). You should use only the brand-name that your doctor prescribes, since generic brands may not be as reliable. Name-brand levothyroxine pills include Synthroid®, Levoxyl®, Levothroid®, Euthyrox®, and Eltroxin®.
Patients sometimes take more pills than they should, trying to speed up the treatment or lose weight. However, this can lead to hyperthyroidism and long term complications, such as osteoporosis. You should take the pills as your doctor prescribes.
At different times in your life, you may need to take different amounts of thyroid hormone. Therefore, you should see your doctor at least once a year to make sure everything is all right.
® Synthroid is a registered trademark of Knoll Pharmaceuticals.
® Levoxyl is a registered trademark of Jones Medical Industries.
® Levothroid is a registered trademark of Forest Pharmaceuticals.
® Euthyrox is a registered trademark of EM Pharma.
® Eltroxin is a registered trademark of Roberts Pharmaceuticals.
Are thyroid hormone pills needed after treatment for hyperthyroidism?
Many patients treated for hyperthyroidism become hypothyroid. They will need to take thyroid hormone pills for the rest of their lives. In addition, they will need to see their doctor at least once a year.
How does thyroid disease affect my cholesterol level?
One of the observed side effects of hypothyroidism is an elevation of LDL cholesterol, the “bad cholesterol.” Elevated LDL levels have been associated with heart disease, particularly coronary artery disease, and peripheral vascular disease. Elevated triglycerides also pose a serious medical problem. However, only in the most severe cases of hypothyroidism does the disease cause a marked elevation in triglyceride levels.
The “good cholesterol” is called HDL cholesterol. Scientific studies are inconclusive about the effects of hypothyroidism on HDL levels. Some have shown a decrease; others have shown no change; and a few have shown a minimal increase.
All patients with hypercholesterolemia (high cholesterol) should have tests of their thyroid function since a small percentage of these patients will have hypothyroidism contributing to their cholesterol problem. Treatment with thyroid hormone will lower cholesterol levels in those patients with an abnormal cholesterol from hypothyroidism.
The overall effect of hypothyroidism is a significant increase in the bad cholesterol. Long-standing, untreated hypothyroidism can lead to permanent damage to the coronary arteries and other blood vessels. Therefore, it is important to treat hypothyroidism and monitor cholesterol levels closely.
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Some of the obvious symptoms of overt hypothyroidism are:
- skin irritations
- susceptibility to cold
- high rate of dehydration
- disorders in menstrual cycles of women
- very low immunity
- enlarged thyroid gland due to inflammation
- sudden weight gain
- increase in the chances of the blood pressure and other heart disorders
- swelling around the eyes and nose
Treatment Of Overt Hypothyroidism
Overt hypothyroidism is not fully curable but if treated early enough shouldn’t do further harm to the body. Treatment usually consists of thyroxine hormone replacement therapy and is lifelong. A clinical assessment and thyroid function tests are usually done around 6 weeks after treatment starts and any adjustments made accordingly. Regular and ongoing assessments are required.