Hypothyroidism and Heart Rate: Unveiling Heart Disease Risks
The thyroid plays a critical role in maintaining overall health. This small butterfly-shaped gland located in the neck makes and releases different hormones that affect a variety of functions in the body. While the main function of this small but mighty gland is to control the body’s metabolism, the thyroid and its hormones impact nearly every organ in the body, including the heart. When the thyroid malfunctions, essentially the whole body is affected.
There are several kinds of thyroid disorders that occur, but hypothyroidism–meaning an underactive thyroid–is the most common. According to the NIH, between 4% and 10% of the population are impacted by hypothyroidism. While an under-performing metabolism and low energy levels are commonly associated with hypothyroidism, heart disease is a lesser-known yet critical connection. In this blog post, we are diving into the relationship between hypothyroidism and heart rate, exploring the potential risks and how they can be ameliorated.
Can the Thyroid Cause Heart Problems?
Because of the thyroid’s intricate connection to the cardiovascular system, thyroid dysfunction such as hypothyroidism does negatively impact the heart. This close relationship between the heart and the thyroid is due to the hormones it produces, thyroxine (T4) and triiodothyronine (T3). Both of these hormones influence the heart–which is a highly metabolic organ. When the thyroid is underactive and T4 and T3 hormones drop, it results in reduced cardiac output, meaning the heart pumps blood less efficiently. Several studies have suggested a link between hypothyroidism and the increased risk of various heart conditions.
How Does Hypothyroidism Affect Heart Rate?
Hypothyroidism can significantly influence a person’s heart rate. Diminished levels of T4 and T3 hormones can result in an attenuated response to the sympathetic nervous system, which typically stimulates an increased heart rate. Consequently, individuals with hypothyroidism often experience bradycardia—a condition characterized by an abnormally slow heart rate. (In adults, a resting heart rate of fewer than 60 BPM qualifies as bradycardia.) This deceleration of the heart is attributed to the heart's reduced sensitivity to the signaling effects of thyroid hormones, leading to a delayed response to the body's need for heightened cardiac output. The prevalence of hypothyroidism means that many individuals experience bradycardia and other heart rate irregularities, whether or not they are aware of it.
Chest Pain and Thyroid: Unraveling the Connection
Hypothyroidism is accompanied by a host of unwanted symptoms which show up in varying degrees from person to person. They include fatigue, slow speech, dull facial expressions, a sensitivity to being cold, weight gain, puffiness in the face, a hoarse voice, constipation, carpal tunnel syndrome, thinning eyebrows, and coarse or dry hair. Chest pain is another symptom that frequently accompanies hypothyroidism and should not be overlooked.
Hypothyroidism can cause chest pain through the development of atherosclerosis, driven by altered lipid metabolism and elevated LDL-C levels (also known as “bad” cholesterol). This condition leads to arterial plaque formation, which narrows coronary arteries and reduces blood flow to the heart, resulting in chest pain. Additionally, hypothyroidism increases systemic vascular resistance and blood pressure, straining the heart. The combination of reduced blood supply and increased cardiac workload may cause angina, a condition characterized by chest pain. Hypothyroidism-induced changes in heart contractility and relaxation further exacerbate the cardiac workload, contributing to chest discomfort.
The connection between hypothyroidism and chest pain underscores the importance of careful medical assessment and monitoring to mitigate cardiovascular risks and various symptoms. Something else to note about the symptoms of hypothyroidism is that many of them are shared by depression and anxiety. For instance, chest pain, fatigue, and slow speech are all indicators of these mental health concerns–but they can also indicate hypothyroidism. To properly diagnose the root cause of symptoms such as chest pain, it’s important to seek proper medical evaluation. Hypothyroidism is tested for through a combination of clinical assessments and lab tests administered by your doctor.
What Time of Day Is Hypothyroidism Worse?
Circadian rhythms play a pivotal role in thyroid function by influencing hormone production throughout the day. For individuals with an under-performing thyroid, the body is less able to meet the heightened energy demands associated with the circadian cycle’s morning surge. For this reason, many people with hypothyroidism find mornings to be especially challenging. Morning fatigue, stiffness, and reduced cognitive functioning are common complaints, reflecting the body’s slower metabolic rate. Because people with hypothyroidism often experience an extended and intense energy deficit, their ability to be energetic can wane throughout the day.
Understanding the 3 PM Thyroid Crash
The “3 PM thyroid crash” is a phenomenon in which people with hypothyroidism experience an intense afternoon energy slump. While the average person’s energy wanes naturally in the afternoon, individuals with hypothyroidism often feel especially tired at this time, because they have especially limited energy reserves. Some practical strategies to manage the 3 PM thyroid crash include prioritizing sleep, regular physical activity, hydration, balanced nutrition (including healthy afternoon snacking), and short mental breaks. People with hypothyroidism can also work with their healthcare provider to optimize the timing, type, and dosage of their medication, all of which can impact their circadian rhythm and energy needs.
Can Hypothyroidism Cause Irregular Heartbeat?
Arrhythmia, or a condition that is characterized by an irregular heartbeat, has been found to be yet another result of hypothyroidism. Because the thyroid gland produces insufficient hormones, alterations in the electrical properties of the heart can occur. Thyroid hormones play a crucial role in maintaining the normal rhythm and contractility of the heart. When levels are low, it can lead to prolonged QT intervals on the electrocardiogram (ECG), potentially increasing the risk of arrhythmias. It is especially important to get your thyroid evaluated and treated by a medical professional if you experience irregular heart rhythms.
Managing Hypothyroidism for Heart Health
Thyroid replacement therapy (TRT) is a valuable medical treatment that benefits many people with hypothyroidism and the associated risks to heart health. TRT addresses hormonal deficiencies or imbalances in the body by supplementing or replacing hormones. In addition to TRT, people with hypothyroidism can make various lifestyle changes to manage their symptoms. Adequate sleep, hydration, proper nutrition (including reducing the intake of goitrogens, a category of food that can limit thyroid function), and supplements like Vitamin D and selenium can all work in favor of your thyroid, and by a consequence, your heart health.
To monitor your thyroid and receive treatments such as thyroid replacement therapy, it is important to seek medical attention from a physician. Not only will your thyroid benefit, but your heart—and many other organs in your body—will benefit, too. For the most effective help, it’s essential for endocrinologists and cardiologists to collaborate, resulting in fully comprehensive medical care.
All in all, understanding the intricate connection between hypothyroidism and heart health is crucial for maintaining overall health. Through careful and regular thyroid evaluation, thyroid replacement therapy, and proper lifestyle changes, individuals can effectively manage their hypothyroidism and mitigate the potential risks of heart disease.
If you struggle with hypothyroidism or suspect you may have it, Dr. Stracks at Cormendi Health can help. Dr. Stracks is a seasoned professional and expert in helping patients identify and treat thyroid conditions. Through a series of in-depth tests and a carefully calibrated dosage of medication, he’ll help you treat your symptoms, improve your health, and get back to feeling like yourself. Because you deserve to live a life you love, without hypothyroidism holding you back.
