A new study published in Neurology has revealed that older people suffering from thyroid problems, such as hypothyroidism, have a higher risk than others of developing dementia. Furthermore, this risk increases for people who undergo thyroid hormone replacement therapy.
But what is hypothyroidism?
Hypothyroidism is a disease that causes the thyroid gland to reduce the number of thyroid hormones it produces. This leads to symptoms such as fatigue, weight fluctuations, especially in the gain direction, and increased sensitivity to cold.
Neuroscience News quoted Chien-Hsiang Weng, MD, MPH, the author of the study, who stated that
in some cases, thyroid disorders have been associated with dementia symptoms that can be reversible with treatment.
He also added that more research is necessary in order to issue a clear confirmation of this aspect, but that people should keep in mind that thyroid problems may lead to dementia, but that there are treatments that can prevent it or slow it down.
How the research was done
The study analyzed data from 7843 people recently diagnosed with dementia, with an average age of 75. From this group, researchers tried to identify the ones who had thyroid issues, dividing them in two groups. One group included people suffering from hypothyroidism, while the other included people that had hyperthyroidism (or overactive thyroid, with symptoms opposite to those of hypothyroidism: rapid weight loss, increased heartbeat and anxiety).
After gathering and interpreting all the necessary information, the authors of the study found a connection to the onset of dementia only in people who suffered from hypothyroidism. After ruling out other factors that could lead to disease, researchers concluded that people above 65 who had a history of hypothyroidism had 80% more chances of developing dementia than people from the same age category without thyroid problems. At the same time, they found no connection between hyperthyroidism and dementia.
However, the research team emphasized that the study is not necessarily proof that hypothyroidism causes dementia, but that there is a connection between the two.