Low Blood Pressure (Hypotension) - Symptoms, Diagnosis, and Treatment

What is Low Blood Pressure?

Low blood pressure is medically known as hypotension. Someone with hypotension has a lower than expected pressure in the body's arteries (which is pumped from the heart). Although high blood pressure may require medical treatment to prevent chronic disease, low blood pressure is less concerning for doctors. Those with regular hypotension can live fit and healthy lives. However, in some cases, this can be dangerous if it significantly decreases blood flow and oxygen supply to the brain.

Low Blood Pressure Range

Normal blood pressure ranges can depend on your characteristics (e.g. gender, height, age, etc.) However, for the general public, low blood pressure is classified as:

Less than 90mmHg systolic blood pressure and/or
Less than 60mmHg diastolic blood pressure

In summary, anything less than 90/60 can be seen as the range for low blood pressure. However, if it's not causing any unwanted symptoms, then this should not be a problem.

Low Blood Pressure Symptoms

As indicated previously, low blood pressure is usually not concerning unless it's associated with symptoms, such as:

Dizzy
Lightheadedness
Fainting
Headaches and migraines
Dehydration and feeling unusually thirst
Fatigue or feeling low energy and tired
Blurry vision
Loss of focus

What Causes Low Blood Pressure?

During the day, it's normal for blood pressure to fluctuate between high and low values. This can depend on several factors, such as:

Time of day
Stress and anxiety
Exercise and physical activity
Orthostatic hypotension or postural hypotension that occurs with rapid positional changes (i.e. sitting to standing).
Recovery after surgery
Fitness levels
Diet

Long-term causes of low blood pressure

Outside of these day-to-day formalities that can cause hypotension, some circumstances can lead to long-term changes. Over time, these can lead to permanent or temporary changes in blood pressure, which may or may not lead to noticeable symptoms. These include:

Pregnancy: The increase of progesterone hormones during pregnancy can lead to the relaxation of the blood vessels in the body. Consequently, blood pressure can begin to drop, especially during the first and second trimesters. Feeling faint during these periods, particularly when standing from sitting, is often reported.
Aging: During the ageing process, the risk of high and low blood pressure can gradually begin to increase. Orthostatic hypotension is a primary culprit for the elderly as normal muscle, heart and posture functions become more challenging.
Parkinson's Disease: Similarly, up to 20% of those diagnosed with Parkinson's Disease will experience difficulties with low blood pressure. This is due to the condition's effect on the body's self-regulatory processes, including managing blood pressure during temperature changes, certain positions, physical activity and eating.
Heart Failure: It is estimated that more than 10% of those with heart failure will experience symptoms associated with low blood pressure. As the heart begins to pump less efficiently, less blood will flow around the body.
Diabetes: Those diagnosed with diabetes will experience gradual damage to the nerves that control the body's blood supply. As a result, blood can begin to pool in the legs, which decreases the circulating supply back to the heart. People with this condition are more likely to experience difficulties when changing positions quickly.

Diagnosis

Blood pressure can be tested at home or with trained medical professionals (e.g. GPs, pharmacists, etc.). Usually, they will be accurately able to determine whether blood pressure is high or low. For some, routine blood pressure checks may be required to monitor for general health purposes or specific conditions.

Reading Blood Pressure

Two main numbers represent blood pressure. For example, let's say you get your blood pressure reading back as 120/80. The higher number is known as systolic blood pressure. It shows the pressure into the arteries when the heart contracts. On the other hand, diastolic blood pressure is the lower number and notes the blood pressure in the arteries when the heart is relaxing. As noted earlier, a reading of less than 90/60mmHg may suggest low blood pressure. However, it's essential to consult with a GP to determine the significance of the reading(s) and whether treatment is required.

Tests

Home blood pressure monitors

Home blood pressure monitors are easy to use and can be purchased at a local pharmacy. The arm cuff is usually attached to the machine, which measures the pressure of the arteries of the arm. Blood pressure is determined as the cuff squeezes the arm while looking for a pulse. However, it's crucial to use a validated monitor to ensure accurate assessments.

Visiting a GP

The most accurate blood pressure readings are taken manually with a trained professional. GPs will regularly use a device called a sphygmomanometer and stethoscope to measure blood pressure. Measurements are taken similarly to a home blood pressure monitor but are generally more sensitive.

Low Blood Pressure Treatment

As noted earlier, not all people with regular hypotension will require treatment. However, those with symptoms associated with it may need to consult a GP about managing blood pressure. To determine whether treatment is needed, appropriate tests and examinations may be performed.

How to increase Blood Pressure?

While these treatments can help increase blood pressure, it's best to consult a GP about whether they are safe and effective.

Medication: Certain medications, such as Orvaten can be prescribed against hypotension
Dietary changes: Eating more sodium-rich foods or adding salt to your diet can help elevate blood pressure. Consuming more salt helps the body retain water.
Drinking enough water: A loss of fluid in the body can affect the blood circulating the body. Drinking between 8-10 cups a day can help prevent dehydration which is a known cause of low blood pressure.
Standing up slowly: Changing positions quickly can lead to a sudden drop of blood pressure. Slowly changing postures can help prevent this from occurring.

Complications

Symptoms associated with low blood pressure, including dizziness, fatigue and blurry vision, are usually temporary. Very severe hypotension can result in a loss of blood to the brain, which can cause permanent damage and even death. Additionally, this condition can also result in unintended consequences like losing balance and falling. Particularly for frail people, falling can cause more severe complications, including:

Concussions and brain injury
Fractures
Internal bleeding and bruising
Hospitalisation

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Low Blood Pressure (Hypotension) – Symptoms, Diagnosis, and Treatment