What are the causes of thyroid disorders?
Most often, it is an autoimmune disorder. In hyperthyroidism, the body produces antibodies that stimulate the release of thyroid hormones. It’s Graves’ disease. In hypothyroidism, the antibodies destroy the cells of the thyroid, resulting in decreased synthesis of hormones. It’s Hashimoto’s disease. Some drugs can be disruptive: especially those that contain iodine, such as amiodarone, used against heart rhythm disturbances. Hyperthyroidism can also be due to the presence of one or more excessively functioning nodules or to iodine overload of radiological origin. Conversely, an iodine deficiency can cause hypothyroidism.
Is a nodule necessarily cancerous?
“Thyroid nodules are very common, but the majority of them are not cancerous,” reassures Pr Marie-Christine Vantyghem, endocrinologist. When one is detected on palpation, the doctor orders an ultrasound. This makes it possible to differentiate the benign nodules from those which are suspicious. If cancer is suspected, a fine needle aspiration is done. It is this which makes it possible to orient or not towards a thyroid cancer.
If you have hypothyroidism, should you consume more iodine?
The thyroid requires a daily intake of 150 µg (micrograms) of iodine in adolescence and adulthood, 200 µg during pregnancy. pregnancy and breastfeeding. It is found in foods of marine origin (Pisces, crustaceans, shellfish …),
but also in eggs, dairy and grain products and some fruits and vegetables (beans). In mountainous areas (where these products are not widely consumed), severe iodine deficiency led (and still does in some countries) a form of hypothyroidism with goiter. That is, with an increase in the volume of the gland, which tries to produce more hormones, associated with mental retardation. This is the origin of the famous insult of Captain Haddock: “Alpine moron”! At the instigation of the WHO (World Health Organization), most countries have opted for iodization of salt: manufacturers are now required to add 10 to 15 µg of iodine per gram of salt. And severe iodine deficiency has become very infrequent. “Supplementation is therefore rarely necessary, except during pregnancy,” says Professor Vantyghem.
Do the nodules need to be operated on?
The presence of nodules in the thyroid is a very common phenomenon, which increases with age. Many have no symptoms or are not bothersome. Surgery is necessary when the nodule is cancerous, if the size of the gland poses a risk of compression or the hormonal hypersecretion is difficult to limit with drugs. Thyroid ablation can be partial (a single localized nodule or a small tumor) or most often total (several nodules, diffuse tumor). In the second case, the patient will then have to take levothyroxine to compensate for the lack of thyroid hormones. “After the ablation of thyroid cancer, treatment with radioactive iodine may be necessary as an adjunct. Recourse to chemotherapy, on the other hand, is rarely necessary, ”explains Prof. Vantyghem.
Are thyroid cancers more numerous?
Yes, between 1982 and 2012, the number of new cases of thyroid cancer in France increased at a rate of 6% per year! In 2015, it was estimated at 2,783 in men and 7,317 in women, the number of cases observed being higher between 50 and 74 years. But “only” 143 men and 215 women died. “Most thyroid cancers are indeed very treatable,” says Prof. Vantyghem.
How to explain this increase?
It is mainly due to the evolution of medical practices: tumors are better detected, including the smallest, which previously went unnoticed. It is also these microcancers (tumors smaller than 1 cm) that have increased the most. Nevertheless, certain risk factors have been identified, such as for example exposure, during childhood, to ionizing radiation. X-rays should therefore be used sparingly in children.
Did the Chernobyl accident play a role?
In Belarus, Russia and Ukraine, territories heavily contaminated by the fallout from the Chernobyl accident, there was a significant increase in the number of thyroid cancers, especially among those who were children at the time. In France, where the contamination was considered 100 times less important, epidemiological studies have failed to establish a clear link with the nuclear disaster. Curiously, the Bas-Rhin and Haut-Rhin, departments among the most exposed to radioactive fallout from the accident, are, with the Channel, those where the incidence of thyroid cancer is the lowest. Those where the incidence is high are Isère, Gironde and Vendée.
Can alternative medicine help?
“They cannot treat the dysfunction of the thyroid itself”, answers Dr. Valérie Foussier, endocrinologist. But “they can help some patients to better control their stress, which is very difficult for those who suffer from hyperthyroidism. Especially since, as with many autoimmune diseases, stress contributes to the onset of symptoms. »Reduce stress, by meditation, the practice of a sport or the use of certain Natural Healing may therefore have beneficial effects.
Can Levothyrox® be replaced by a generic?
The balance obtained with Levothyrox® is so fragile (called a “narrow therapeutic window”) that this drug is one of the few that pharmacists are not allowed to replace with a generic. However, even if they were allowed to do so, they could not: last year, the generic marketed by Biogaran was withdrawn from the market due to a problem with the stability of the active ingredient. But following the affair of Levothyrox®, the laboratory announced on September 19 that it was going to relaunch production. In any case, if the medication you are taking is not a problem, it is better not to change it. If it is a first prescription, the choice of the generic can be discussed with the doctor.
What tests to explore the thyroid?
In the event of symptoms suggesting thyroid disorders, the doctor begins by palpating the gland and evaluating its function by taking a blood test. It is only in the event of an anomaly that the other two examinations may be requested.
Read also:
Hyperthyroidism: recognizing the symptoms
Thyroid: increasingly precise examinations