Dizziness is a common and multifaceted symptom that affects a substantial portion of the population.

It can have a significant impact on an individual's quality of life and may be associated with various underlying causes. It is a subjective sensation of lightheadedness or unsteadiness. It is different from the feeling that the environment is “spinning”, as the latter refers to vertigo.

While they could overlap in their description and causes, dizziness and vertigo have different diagnostic approach and treatments. The purpose of this article is to discuss dizziness, but it is worth noticing that vertigo more often than not is related to an ear (vestibular) or a posterior brain condition (cerebellar). On the other hand, dizziness can arise from numerous factors involving the heart, the vessels, the central nervous system and also from psychological influences.

When dizziness gets to be severe, it could lead to fainting, “syncope”, or an almost-fainting sensation, “presyncope”.

What can cause dizziness?

∎ Orthostatic hypotension

It occurs when blood pressure drops significantly upon standing up, leading to inadequate blood flow to the brain, and hence dizziness. This can result from dehydration, autonomic nervous system dysfunction and certain medical conditions such as diabetes as they damage the blood vessels and their nerve endings, leading to an abnormal response when standing up. In addition, orthostatic hypotension can be caused by certain medications such as antihypertension ones, sedatives or antidepressants.

∎ Arrhythmias

Irregular heart rhythms, such as atrial fibrillation or bradycardia (slow heart rate), can cause insufficient or erratic blood flow to the brain, resulting in dizziness.

∎ Disease of the carotid vessels, heart failure from coronary disease, cardiomyopathies or valve disorders

These can all impair blood flow and oxygen delivery to the brain, leading to dizziness.

∎ Metabolic disorders

Hypoglycaemia (low blood sugar), electrolyte imbalances, anaemia or thyroid disorders can contribute to dizziness by directly affecting normal brain function or blood circulation.

∎ Stroke

The most common type of stroke occurs when a clot forms inside a brain blood vessel, interrupting blood supply to that special cerebral area and leading to neurological symptoms such as dizziness, with or without movement limitation, numbness in the body or speech alteration.

∎ Migraines

These are severe headaches that could be accompanied by dizziness. Some individuals may experience dizziness as the primary symptom with or without headache (“aura’).

∎ Multiple sclerosis (MS)

MS is an autoimmune disease that affects the central nervous system. Dizziness can arise owing to damage to the nerves responsible for balance and co-ordination.

∎ Brain tumours

They can cause dizziness by exerting pressure on the surrounding structures or affecting normal brain function.

How can the cause of dizziness be identified?

∎ Medical history

Obtaining a detailed medical history is the initial and most important step in the diagnostic process. The healthcare provider will inquire about the characteristics of the dizziness, including onset, duration, triggers, associated symptoms and any relevant medical conditions or medications. This information helps to narrow down the potential causes and guides further evaluation.

∎ Physical examination

A thorough cardiac and neurological examination, including baseline blood pressure measurement, is done to identify any physical signs related to dizziness.

∎ Orthostatic BP assessment

This involves measuring blood pressure while lying down, sitting and standing. A significant drop in blood pressure upon change in body position should be evaluated further.

∎ Neurological work-up:

1, Computed tomography scans use X-rays to create cross-sectional images of the brain. While not as sensitive as MRI in detecting certain abnormalities, CT scans can be valuable in emergency situations or when MRI is contraindicated. CT scans are particularly useful in identifying acute haemorrhages, skull fractures or other traumatic brain injuries that may be contributing to dizziness.

2, Magnetic Resonance Imaging is the most commonly used neuro-imaging modality for evaluating dizziness. It provides detailed images of the brain's anatomy and helps to identify structural abnormalities or lesions that may contribute to dizziness, such as brain tumours, strokes, multiple sclerosis or vascular malformations.

3, Carotid ultrasound uses sound waves to evaluate the blood flow in the carotid arteries, which supply blood to the brain. It can detect any narrowing or blockages in these arteries that may contribute to dizziness.

∎ Cardiovascular work-up

1, An electrocardiogram records the electrical activity of the heart. It helps to identify arrhythmias, electrical conduction abnormalities or other cardiac conditions that may contribute to dizziness.

2, An echocardiogram uses sound waves to create images of the heart's chambers, valves and overall cardiac function. It can help to detect structural abnormalities, such as cardiomyopathies or valve disorders, which may cause dizziness.

3, Cardiac rhythm monitoring uses holter monitors and cardiac event monitors, which are portable devices that individuals wear for 24 hours or up to several weeks to record the heart's electrical activity during symptoms of dizziness. They allow for correlation between symptoms and possible cardiac arrhythmias.

4, Ambulatory blood pressure monitoring is a method of measuring blood pressure over a 24-hour period while the individual carries out their regular activities. It can help to identify abnormal BP patterns, such as significant drops or spikes that might be associated with dizziness and that could go unnoticed during a routine clinic measurements.

5, Blood tests may be conducted to assess various factors, including blood sugar levels, electrolyte balance, complete blood count (CBC), thyroid function or specific markers related to certain conditions.

Based on this work-up, a tailored treatment would be offered to cure or at least mitigate the dizziness problem.

• Joe Yammine, MD is a consultant cardiologist at the Bermuda Hospitals Board. The information here is not intended as medical advice nor as a substitute for professional medical opinion. Always seek the advice of your physician.