A new study from the University of Michigan has revealed a possible link between the strength of thyroid hormone treatment and a higher risk of dying from heart-related causes.
The research, led by Dr. Maria Papaleontiou and published in JAMA Network Open, sheds light on how a widely used treatment could affect heart health.
Levothyroxine is a man-made thyroid hormone. It is one of the most commonly prescribed medications in the United States. It helps people with thyroid problems by replacing or supporting the natural thyroid hormone in their bodies. However, until now, we didn’t fully understand how this drug might impact the heart.
Heart disease is still the top cause of death in the U.S., affecting nearly half of adults over the age of 20. Since so many people take thyroid medication, it’s important to explore whether it could affect heart health.
This new study looked at medical data from over 705,000 U.S. veterans who were treated with thyroid hormones between 2004 and 2017. The researchers wanted to know whether having too much or too little thyroid hormone could raise the risk of dying from heart-related problems.
They found that up to half of the people on thyroid hormone treatment had hormone levels that were either too high or too low. These conditions are known as exogenous hyperthyroidism (too much hormone) and hypothyroidism (too little hormone). Both were linked to a greater risk of death due to heart problems.
The researchers paid special attention to a hormone called thyrotropin, which helps control how much thyroid hormone the body makes. When thyrotropin levels were below 0.1 or above 20 (measured in mIU/L), the risk of heart-related death went up. This means that keeping thyroid hormone treatment within the right range may help protect heart health.
Older adults were found to be especially at risk if their thyroid hormone levels weren’t well controlled. This suggests that doctors should be extra careful when treating older patients with thyroid problems.
To make sure the results were accurate, the researchers did not include people who had thyroid cancer or were taking other drugs like lithium or amiodarone, which can change how the thyroid works.
This study is important because it shows that the way thyroid hormone is given could be a factor in preventing heart problems. Keeping thyroid levels balanced—known as euthyroidism—is important not only for thyroid health but also for protecting the heart.
In summary, the study encourages patients and doctors to carefully monitor thyroid hormone levels during treatment. Avoiding too much or too little hormone could reduce the risk of heart disease and death, especially in older adults.
If you care about heart health, please read studies that Changing blood pressure readings is a hidden sign of heart disease and common type 2 diabetes drugs may raise heart risk.
If you care about heart health, please read studies about root cause of heart rhythm disorders and Warning signal from the kidneys can predict future heart failure risk.
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