Your Thyroid and Your Mood
The association of thyroid dysfunction with alterations in mood and cognition has been recognised since some of the earliest descriptions of thyroid disease. Over the years, researchers have aimed to further define these effects throughout the spectrum of thyroid disorders, to better understand the underlying condition and refine indications for treatment.
More recently, attention has turned towards examining the impact of differences in thyroid hormones within the normal reference range, particularly in older adults, providing new insights into the association of thyroid hormone with cognitive decline.
This review, by like Richie and Yeap (2015), summarises the evidence assessing the influence of thyroid hormone on mood and cognition in overt and subclinical hypothyroidism, within the reference range, and in subclinical and overt hyperthyroidism.
Treatment of overt thyroid dysfunction largely resolves associated disturbances in mood and cognitive dysfunction, however in the setting of overt hypothyroidism subtle detrimental effects on cognition may not be fully reversed. Subclinical hyperthyroidism and higher free thyroxine (FT4) within the normal range have been associated with poorer cognitive outcomes.
Ritchie and Yeap recommended that more research is undertaken on the cause and effect of this. They also noted that more research would help to guide practitioners in assessing the benefits vs the risks of medication in the increasing population of older adults with subclinical thyroid disease. This highlights that many older people are not treated. It is assumed that thyroid function will decline with age and that often, as patients are already on medications for heart disease, high blood pressure, or high cholesterol, treating the patient for hypothyroidism is a lower priority.
However, at Napiers we still believe that hypothyroidism in elderly patient should not be overlooked. There is a proven link between cardiac problems, diabetes and other diseases associated with aging. Elderly people should be encouraged to include seaweed in their diet to ensure that they meet at least the minimum iodine RDA in order to prolong thyroid health for as long as possible.
Ritchie M, Yeap BB. Thyroid hormone: Influences on mood and cognition in adults. Maturitas. 2015 Jun;81(2):266-75. doi: 10.1016/j.maturitas.2015.03.016.