Atrial fibrillation and subclinical hyperthyroidism (and gluten sensitivity)

It's necessary to bear in mind when dealing with atrial fibrillation that subclinical hyperthyroidism is a common cause. Subclinical means that there are symptoms from excess thyroid hormone activity even though the lab values appear normal. There are a plethora of recent studies that investigate this phenomenon; here are a few. The authors of the first paper state: "Overt and subclinical hyperthyroidism are both well-known independent risk factors for atrial fibrillation."

1. High-Normal Thyroid Function and Risk of Atrial Fibrillation
2. Activation of Electrical Triggers of Atrial Fibrillation in Hyperthyroidism
3. Atrial fibrillation and heart attack associated with subclinical hyperthyroidism
4. Atrial fibrillation associated with exogenous subclinical hyperthyroidism
5. The mechanisms of atrial fibrillation in hyperthyroidism
6. Effects of Thyroid Hormone on the Cardiovascular System
7. Association Between Serum Free Thyroxine Concentration and Atrial Fibrillation

Now the plot thickens. Here is a paper recently published in Nature Reviews Endocrinology discussing the link between celiac disease (gluten sensitivity) and autoimmune thyroiditis. Here is another, fresh off the presses, from the journal Gut. One more for now: this paper published in the journal Thyroid demonstrates that the antibodies involved in celiac disease also bind to thyroid follicles.