Thyroid conditions and diabetes are the two most frequent hormonal problems general practitioners encounter in their daily practice.Today diabetes is grouped in two main forms: type 1 and type 2 diabetes. Both type 1 and 2 diabetes can occur in people diagnosed with Hashimoto’s and an Thyroid disease is a pathological state that can adversely affect diabetes control and has the potential to negatively affect patient outcomes. Diabetes A chronic condition caused by higher than normal blood sugar levels due to the inability of the body to process the sugars. The prevalence of thyroid disease in the general population is estimated to be 6.6%, with hypothyroidism the most common malady. Because patients with one organ-specific autoimmune disease are at risk of developing other autoimmune disorders. In young women with type 1 diabetes, there is a high incidence of autoimmune thyroid disorders.
Thyroid function and diabetes
Thyroid hormones are necessary for the body to metabolize carbohydrates, as well as for the pancreas to properly function (the organ producing insulin). Low thyroid hormones cause a drop in insulin levels — insulin is a hormone needed to take sugar from the blood to different cells throughout the body.
Low insulin levels cause high blood sugar levels and slows down in cellular function, including muscle contractions and basic brain function. Over longer periods of time low insulin levels can trigger diabetes.
Hypothyroidism and Diabetes
Hypothyroidism is caused by thyroid gland producing too little thyroid hormone. The most common form of hypothyroidism is an disease called Hashimoto’s thyroiditis. Symptoms include:
- Fatigue
- Lethargy
- Depression
- Constipation
- Weight gain
- Low blood pressure
- Slow pulse
- Intolerance to cold
Hypothyroidism causes many metabolic abnormalities as well as multiple clinical symptoms. Some studies suggest that blood sugar may be affected in hypothyroidism and levels may increase. Indeed, it has been noted that patients with diabetes who also have hypothyroidism may have higher levels of Hemoglobin A1C (HBA1C). This test is done to diagnose and monitor control of blood sugar by patients with diabetes. An elevated HBA1C usually indicates worse control of diabetes.
Although wide-ranging changes in carbohydrate metabolism are seen in hypothyroidism. More importantly, hypothyroidism is accompanied by a variety of abnormalities in plasma lipid metabolism, including elevated triglyceride and low-density lipoprotein (LDL) cholesterol concentrations. Even subclinical hypothyroidism can exacerbate the coexisting dyslipidemia commonly found in type 2 diabetes and further increase the risk of cardiovascular diseases.
Hypothyroidism and hypoglycemia
Hypothyroidism causes your metabolism to slow and the medications you take, including insulin, stay active longer than they normally would. You may find that your blood glucose levels are lower than they are normally, and you may experience hypoglycemia or low blood sugar. Until the condition is treated it may be necessary to reduce your dose of insulin or oral medication to prevent low blood glucose. People are at an increased risk of frequent hypoglycemic episodes with an underactive thyroid and low blood sugar symptoms include:
- Shakiness
- Weakness
- Confusion
- Problems talking
- A feeling of hunger
- Loss of consciousness (in extreme cases)
Hypothyroidism and insulin resistance
Both clinical and subclinical hypothyroidism are connected to insulin resistance, a state where cells in the body stop responding to insulin’s signal to take sugar out of the blood. This results in high blood sugar levels, directly increasing the risk of eye damage and kidney damage (2–4). Insulin resistance can cause the thyroid gland to develop more nodules and become larger in size (5, 6).Symptoms of insulin resistance include:
- Fatigue
- Hunger
- Brain fog
- Weight gain (especially around the belly)
- High blood pressure
Management of Thyroid Dysfunction
hypothyroidism should be treated with thyroid hormone therapy. L-thyroxine is the most widely used thyroid hormone replacement. Natural thyroid extracts such as desiccated thyroid should no longer be used. hypothyroidism should be treated with thyroid hormone therapy. L-thyroxine is the most widely used thyroid hormone replacement. Natural thyroid extracts such as desiccated thyroid should no longer be used. With progression to complete thyroid failure, there is usually a need to increase the thyroxine dose with time. In diabetic patients with underlying coronary artery disease, L-thyroxine therapy may exacerbate angina by increasing myocardial contractility and heart rate. Therefore, it is best to start with a low dose, such as 25 µg daily, and increase slowly by monthly increments of 25 µg while monitoring the patient’s clinical status and serum TSH levels.
Prevention and Management
- If you have already been diagnosed with thyroid disease or diabetes, weight management is considered among the most effective strategies for the prevention of the other condition.
- Maintaining close control over your glucose and thyroid hormone levels can help prevent diabetes if you have thyroid disease. And maintaining optimal glucose levels can reduce your chances of developing thyroid disease if you have diabetes.
- If you have low insulin or insulin resistance, thyroid disease can make your blood glucose levels fluctuate more than usual and become harder to manage. Optimal control of thyroid hormone levels and glucose levels with medication and diet is vital to preventing the long-term complications of both of these conditions.
- Because there is a significant risk of thyroid problems for those with type 1 diabetes, the American Diabetes Association (ADA) recommends that everyone with type 1 diabetes be tested for hypothyroidism soon after their diagnosis. Even if results are normal, the ADA recommends follow-up tests be performed at least once every two years.
References
https://spectrum.diabetesjournals.org/content/19/3/148
https://www.verywellhealth.com/thyroid-disease-and-diabetes-3289616
http://journal.diabetes.org/clinicaldiabetes/v18n12000/pg38.htm
https://www.boostthyroid.com/blog/2019/5/17/diabetes-hashimotos-and-an-underactive-thyroid
