A recent study suggests that older individuals with hypothyroidism, or underactive thyroid, may face an elevated risk of developing dementia. This risk appears to be particularly heightened in those who require thyroid hormone replacement therapy. Hypothyroidism arises when the thyroid gland fails to produce sufficient thyroid hormones, leading to a sluggish metabolism and symptoms such as fatigue, weight gain, and cold sensitivity.
Dr. Chien-Hsiang Weng, a clinical assistant professor of family medicine at Brown University’s Warren Alpert Medical School and the lead author of the study published in Neurology, notes that certain cases of thyroid disorders have shown symptoms akin to dementia, which could be reversible with proper treatment. However, further research is warranted to validate these findings. Weng emphasizes the importance of recognizing thyroid issues as a potential risk factor for dementia and highlights available treatments that might mitigate irreversible cognitive decline.
The research, involving the analysis of health records from 7,843 individuals newly diagnosed with dementia in Taiwan, scrutinized the correlation between thyroid disorders and dementia risk. Among the participants, aged around 75 on average, the researchers identified cases of hypothyroidism and hyperthyroidism. Hyperthyroidism, characterized by an excess of thyroid hormone production, was not found to be associated with dementia risk in the study.
Regarding hypothyroidism, 0.9% of those with dementia had this condition, compared to 0.4% of those without dementia. Upon adjusting for various factors like age, sex, high blood pressure, and diabetes, the study revealed that individuals over 65 with hypothyroidism were 80% more likely to develop dementia than their counterparts without thyroid issues. Notably, this increased risk was not observed in individuals under 65 with a history of hypothyroidism.
Further analysis showed that individuals who underwent medication for hypothyroidism were three times more likely to develop dementia compared to those who did not require medication. This finding suggests a possible link between the severity of hypothyroid symptoms necessitating treatment and the risk of dementia.
It's essential to note that this observational study establishes an association rather than causation between hypothyroidism and dementia. Additionally, the study's limitation includes the lack of consideration for the severity of individual hypothyroid cases.
