Fibromyalgia and Thyroid Disease
Fibromyalgia and thyroid disease are strongly linked. Up to 15% of patients with hypothyroidism will develop fibromyalgia, a link that has led scientists to investigate the possibility that both diseases have the same underlying cause.
What is the Thyroid Gland?
The thyroid gland is located in the neck, around the region of the Adam’s apple and is responsible for producing thyroid hormones when stimulated by the hypothalamus (which is a part of the brain). Thyroid hormones play a number of roles in the body. They affect metabolism, protein synthesis, bone growth and even determine the sensitivity of the body to other hormones like adrenaline. Thyroid hormones even play a role in sleep cycles in humans and in hibernation cycles in other mammals
What is Hypothyroidism (under active)?
Hypothyroidism is a condition characterised by abnormally low thyroid hormone production. There are many disorders that result in hypothyroidism. These disorders may directly or indirectly involve the thyroid gland. Because thyroid hormone affects growth, development, and many cellular processes, inadequate thyroid hormone has widespread consequences for the body. Hypothyroidism causes a general slowing down of your body's functions. Some of the symptoms include:
- feeling tired and sleeping a lot
- feeling the cold easily
- dry and/or pale skin
- coarse, thinning hair and brittle nails
- sore muscles, slow movements and weakness
- a hoarse or croaky voice
- problems with memory and concentration
- weight gain
- fertility problems and increased risk of miscarriage
- heavy, irregular or prolonged menstrual periods
- a slow heart rate
What is Hyperthyroidism (over active)?
Hyperthyroidism means an overactive thyroid gland. When your thyroid gland is overactive it makes too much thyroxin. The extra thyroxin causes many of your body's functions to speed up. The following are symptoms of hyperthyroidism:
- being restless, nervous, emotional, irritable, sleeping poorly and 'always on the go'.
- tremor of your hands.
- losing weight despite an increased appetite.
- sweating, a dislike of heat and an increased thirst.
- diarrhea or needing to go to the toilet to pass feces more often than normal.
- shortness of breath.
- skin problems such as hair thinning and itch.
- menstrual changes - your periods may become very light or infrequent.
- tiredness and muscle weakness may be a feature.
Fibromyalgia and Thyroid Hormone: The Link
Two facts about thyroid hormones are pertinent to fibromyalgia, their role in sleep and their role in setting hormone sensitivity. Fibromyalgia is thought to be the result of an increase in sensitivity to pain as a result of neurochemical imbalances in the brain and spinal cord. It is thought that fibromyalgia and thyroid hormone may be linked as a result of the ability of thyroid hormone to set the body’s sensitivity to a number of hormones. Though no direct effect has been linked, thyroid hormone is known to affect levels of serotonin, one of the major brain chemicals implicated in the pathology of fibromyalgia.
Another important link between fibromyalgia and thyroid hormone is the role that thyroid hormone has in regulating sleep cycles. Because disorder sleep is a major component of fibromyalgia, it is speculated the sleep regulation may play a role in the development of the disease or at least be the result of the same disease-causing mechanism.
The clinical features of fibromyalgia and hypothyroidism are virtually the same. The most common symptoms of fibromyalgia are also common symptoms of hypothyroidism, and the objective abnormalities of Fibro are also objective abnormalities of hypothyroidism. The symptoms and objective abnormalities of hypothyroidism are mediated by inadequate thyroid hormone regulation of cell function. Inadequate thyroid hormone regulation also plausibly mediates the documented features of fibromyalgia.