Definition and Overview
Dizziness is a general term for symptoms in which perception of the position and movement of oneself or the surrounding environment is distorted. According to a large-scale epidemiological survey in Germany, approximately 22.9% of adults experienced moderate or severe dizziness in the past year.
According to the International Vestibular Disease Classification Standards, dizziness is divided into the following four types.
- Vertigo: A feeling that the surroundings are spinning. It is caused by asymmetric signals from the vestibular system.
- Non-rotatory dizziness: Feeling dizzy or shaking in the head. There is no feeling of rotation.
- Presyncope: Feeling as if your vision becomes dark and you are about to collapse. It is caused by decreased cerebral blood flow.
- Disequilibrium: Feeling that it is difficult to maintain balance when walking. It is common in elderly patients.
These four types may overlap with each other, and there are many cases where one patient complains of multiple types at the same time.
cause
The causes of dizziness can be broadly divided into peripheral, central, autonomic, and other causes.
Peripheral causes
Approximately 60-70% of all dizziness patients have peripheral causes. It is caused by a problem with the vestibular organ or vestibular nerve inside the ear. Representative examples include otolithiasis (benign paroxysmal positional vertigo), vestibular neuritis, and Meniere's disease.
central cause
Dizziness occurs when blood flow disorders, tumors, or demyelinating lesions occur in the cerebellum or brain stem. It accounts for approximately 10-15% of all dizziness patients, but it is important to differentiate it because it includes life-threatening diseases such as stroke.
autonomic causes
Representative examples include orthostatic hypotension and vasovagal syncope. If systolic blood pressure drops by more than 20 mmHg when standing up, orthostatic hypotension is diagnosed. Due to autonomic nervous system dysfunction, blood pressure cannot be maintained and cerebral blood flow decreases, causing presyncope or syncope.
Other causes
Anemia, hypoglycemia, drug side effects, anxiety disorders, and hyperventilation syndrome can also cause dizziness.
major diseases
otolithiasis
Benign paroxysmal positional vertigo (BPPV) is the most common dizziness disorder. It accounts for approximately 20-30% of all dizziness patients. Otoliths in the vestibular organ move into the semicircular canal, causing rotational dizziness for a few seconds to a minute when changing posture, such as turning the head or lying down. Symptoms improve in 80-90% of patients with the Epley maneuver.
Meniere's disease
It is caused by excessive endolymph fluid in the inner ear (endolymphatic hydrops). Recurrent rotatory vertigo lasts for 20 minutes to several hours and is accompanied by fluctuating hearing loss, tinnitus, and fullness of the ear. The prevalence is approximately 50 to 200 per 100,000 population.
vestibular neuritis
It is a disease in which the vestibular nerve becomes inflamed, resulting in sudden, severe rotary vertigo that lasts for several days. Viral infection is believed to be the main cause. What differentiates it from Meniere's disease is that it is not accompanied by hearing loss.
Orthostatic hypotension
This is a condition in which systolic blood pressure decreases by more than 20 mmHg or diastolic blood pressure decreases by more than 10 mmHg when standing up from lying down. The prevalence is approximately 15-30% in people over 65 years of age. Dizziness, blurred vision, and fainting occur due to decreased cerebral blood flow.
vasovagal syncope
When the vagus nerve becomes excessively activated due to prolonged standing, pain, tension, etc., blood pressure and heart rate rapidly drop, leading to fainting. It is the most common type, accounting for approximately 21-40% of causes of syncope.
Psychogenic dizziness
A representative example is persistent postural-perceptual dizziness (PPPD). Nonrotational dizziness persists for more than 3 months even after organic vestibular disease does not exist or has recovered. It is often accompanied by anxiety disorders and depression, and vestibular rehabilitation therapy and selective serotonin reuptake inhibitors (SSRIs) are used for treatment.
Signs of Dangerous Dizziness
If the symptoms below are accompanied, a central cause such as stroke should be suspected and an emergency medical facility should be visited immediately.
- Severe dizziness that occurs suddenly and persists regardless of posture.
- Loss of strength or strange sensation in one limb.
- Speech becomes slurred or you cannot understand what other people are saying.
- Objects appear in two (double vision).
- My balance is lost to the point where I can't walk.
- It is accompanied by a severe headache that I have never experienced before.
The HINTS test, which comprehensively evaluates nystagmus pattern, head impulse test, and gaze deviation in patients with acute dizziness, shows higher sensitivity than MRI in distinguishing stroke (about 96% or more within 48 hours of onset).
diagnosis
Determining the cause of dizziness begins with systematic history taking. It is most important to check the type, duration, triggers, and accompanying symptoms of dizziness.
The main diagnostic tests are:
- Nystagmus test: Observe the presence or absence of abnormal eye movements. It is key in differentiating between peripheral and central causes.
- Video head impulse test (vHIT): Evaluates vestibulo-ocular reflex function. Abnormal findings appear in peripheral vestibular diseases.
- Dix-Hallpike test: This is the standard test for diagnosing otolithiasis (BPPV). It is positive if rotational nystagmus is induced in a specific position.
- Electronystagmography (ENG): Quantitatively evaluates left and right differences in vestibular function.
- tilt-table test: Used to diagnose orthostatic hypotension and vasovagal syncope.
- Hearing test: Necessary for diagnosing inner ear diseases such as Meniere's disease.
- Brain MRI: Performed when a central cause is suspected.
life guide
Management of daily life along with treatment for the cause of the disease helps improve symptoms.
- Avoid sudden changes in posture. When getting up from a lying position, sit on the edge of the bed and stay for at least 30 seconds before standing up.
- Maintain sufficient water intake. Drinking 1.5 to 2 liters of water a day helps maintain blood volume.
- Regular aerobic exercise is beneficial for restoring vestibular function and maintaining autonomic balance.
- Avoid lack of sleep and overwork. Fatigue is a major factor that worsens dizziness.
- Reduce excessive caffeine and alcohol intake. These can affect vestibular function and blood pressure regulation.
- If dizziness recurs, record the occurrence, duration, and accompanying symptoms and take them with you to treatment.
If dizziness repeats for more than two weeks or is severe enough to interfere with daily life, you should seek medical attention from a specialist to determine the cause.