Dizziness, headaches, or nausea during a crowded commute or in highly stressful situations may signal a condition known as vasovagal syncope. In 2022, approximately 22,000 people in South Korea sought medical attention for this condition, according to the Health Insurance Review and Assessment Service. However, experts suspect many more cases go undiagnosed due to limited awareness.
To understand vasovagal syncope, it’s essential to grasp the role of the autonomic nervous system, which comprises the sympathetic and parasympathetic nervous systems. These systems work in tandem to maintain the body’s homeostasis. The sympathetic nervous system activates during emergencies, dilating arteries and increasing heart rate, while the parasympathetic system lowers blood pressure and promotes digestion. An imbalance in this system, known as autonomic dysfunction or dysautonomia, can lead to symptoms like headaches, indigestion, dizziness, dry eyes, excessive sweating, chronic fatigue, insomnia, anxiety, and depression.
Vasovagal syncope specifically involves the vagus nerve, a key component of the parasympathetic system that regulates heart rate. When this nerve becomes overactive, it can cause a sudden drop in heart rate and blood pressure, reducing blood flow to the brain and leading to fainting. This condition often arises from an interplay between the sympathetic and parasympathetic systems, where their opposing roles in regulating organ function become disrupted.
Diagnosis typically involves autonomic function tests, such as the tilt-table test, which monitors heart rate, blood pressure, and symptom onset. Other tests, including electrocardiograms, echocardiograms, blood work, and brain MRIs, may be conducted to rule out alternative causes of fainting.
Stressful or frightening situations can overstimulate the sympathetic nervous system, prompting a compensatory overactivation of the parasympathetic system. This can cause a rapid drop in heart rate, temporarily reducing cerebral blood flow and leading to loss of consciousness—a hallmark of vasovagal syncope.
Autonomic dysfunction also manifests in other conditions, such as dysautonomia, which often presents as somatic symptom disorders. For instance, neurogenic gastrointestinal issues, like indigestion or loss of appetite, may occur without visible abnormalities on endoscopic exams, such as gastritis or esophagitis. Poor blood flow to digestive organs or slowed gastrointestinal motility can cause post-meal bloating, gas, or abdominal distension. Conditions like gastroesophageal reflux disease, neurogenic gastritis, and irritable bowel syndrome are common.
Beyond digestive issues, dysautonomia may cause dizziness, sensory disturbances, tinnitus, headaches, mood disorders, and insomnia. Patients may experience facial flushing, fatigue, weakened immunity, frequent infections (e.g., colds, cystitis, or vaginitis), numbness in extremities, brain fog, a sense of pressure in the head, irregular menstruation, dysmenorrhea, premenstrual syndrome, or menopausal symptoms. These signs often point to autonomic nervous system irregularities.
When diagnostic tests show no abnormalities, patients may feel anxious or dismissed. Traditional Korean medicine, including herbal treatments and acupuncture, can help restore autonomic balance and improve health. Lifestyle changes, such as avoiding stress and overwork, ensuring adequate sleep, and engaging in light exercise like walking, are also recommended to promote relaxation and well-being.
Kim Kuk Ju, HEALTH IN NEWS TEAM
press@hinews.co.kr
