What is the association between excess thyroid hormone and dementia? Elizabeth Tracey reports


One in ten older adults takes thyroid hormone, making it one of the most commonly used medicines. Now endocrinologist Jennifer Mammen and colleagues at Johns Hopkins have shown that too much thyroid hormone, called hyperthyroidism, is associated with an increased risk for dementia.

Mammen: We undertook this study to try and clarify the relationship with excess thyroid hormone and cognitive disorders. Most hyperthyroidism is actually a result of excess exposure from treatment and from being on too much thyroid hormone. People do have hyperthyroidism from Graves' disease or toxic nodules but those are actually relatively rare compared to having too much thyroid hormone from just being given a prescription and having the dose be too high.  :28

Mammen says this condition of too much thyroid hormone is called ‘thyrotoxicosis’ and it can be easily assessed with a blood test. At Johns Hopkins, I’m Elizabeth Tracey.