WHAT IS LOW BLOOD PRESSURE?

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While most people are familiar with the dangers of high blood pressure, low blood pressure often flies under the radar because it's typically asymptomatic.

Low blood pressure is also not a stand-alone condition; rather, it's a sign of an underlying health issue – making it that much more essential to get to the bottom of the cause. It can lead to troubling symptoms like dizziness, fainting and fatigue, which can significantly impact everyday life if left untreated.

If you suspect you're experiencing symptoms of low blood pressure, here's what to know about treating the condition and when you should see a doctor.

What Is Low Blood Pressure?

Blood pressure, or the force exerted by your circulating blood against artery walls, is measured using two numbers:

• Systolic, or the top number. This number measures how much pressure the blood is exerting against the artery walls when the heart beats.
• Diastolic, or the bottom number. This number measures pressure in the arteries when the heart is at rest between beats, at its lowest in the phase of circulation.

Low blood pressure, called hypotension, is when your blood pressure reading is lower than 90/60 mm Hg. A normal blood pressure range is considered under 120/80 mm Hg for most healthy adults.

“Low blood pressure is usually a good thing, especially in people that are in adequate health or are physically functional,” says Dr. Spencer D. Liu, an interventional and advanced heart failure transplant cardiologist at Northwell Staten Island University Hospital in New York.

However, when low blood pressure is caused by an underlying condition – which is most often the case – it can require further medical attention.

Causes of Low Blood Pressure

Common causes of low blood pressure may include:

• Dehydration
• Hormonal issues
• Heart problems
• Nutritional deficiencies
• Pregnancy
• Blood loss
• Heat exhaustion or heat stroke
• Severe allergic reactions or infections

What Are the Risk Factors for Low Blood Pressure?

Low blood pressure can affect anyone, though certain risk factors may increase your susceptibility to hypotension.

Age

Older adults are at higher risk for low blood pressure and the symptoms that come with it. That's due to a combination of age-related physiological changes, medication use and prevalence of health conditions.

Certain health conditions

Some conditions, such as diabetes, Parkinson's disease and autonomic neuropathy, can be risk factors for different types of hypotension. In fact, Liu says that low blood pressure is often seen as an initial sign of diabetes.

Some medications

Medications that may increase your risk for low blood pressure include diuretics, antidepressants, drugs to treat Parkinson's disease and erectile dysfunction drugs, especially when combined with other medications like nitroglycerin.

With some medications, however, low blood pressure may be the intended effect.

“People should not be stopping blood pressure medications without consulting their medical provider,” Liu emphasizes.

Types of Low Blood Pressure

There are a few major types of hypotension:

• Orthostatic hypotension, or postural hypotension. OH is a sudden drop in blood pressure that occurs when you go from lying down or sitting to standing. It can be caused by or linked to a number of health conditions, including dehydration, prolonged bed rest, diabetes, anemia and other nutritional deficiencies, and high blood pressure or heart failure. Its prevalence increases with age.
• Postprandial hypotension. This occurs mainly in older adults, and it's when your blood pressure drops after eating. Some health conditions, such as Parkinson 's disease or other nervous system disorders, may put you at higher risk for postprandial hypotension.
• Neurally mediated hypotension. This is when your blood pressure drops after you've been standing for prolonged periods of time.
• Multiple system atrophy with orthostatic hypotension. This rare condition causes low blood pressure while you're standing and high blood pressure while you're lying down.

Symptoms of Low Blood Pressure

Low blood pressure often doesn’t cause noticeable signs or symptoms. However, when symptoms do occur, they may include:

• Dizziness
• Lightheadedness
• Fainting
• Fatigue or weakness
• Headaches
• Blurred vision
• Nausea or vomiting
• Heart palpitations

“Low blood pressure by itself is usually not a concern unless it's causing significant symptoms,” Liu notes.

If you are experiencing symptoms, though, it could be a sign of a medical issue that needs attention.

Diagnosing Low Blood Pressure

To diagnose hypotension, your health care provider will discuss your symptoms and medical history and conduct a physical exam, during which they'll take your vital signs, including your blood pressure.

"Once you identify that, number one, you're having symptomatic hypotension, it's more why," says Dr. Frank Amico, a cardiologist at Chesapeake Regional Healthcare in Chesapeake, Virginia. "And that's really what the question is about: Why are they having it?"

Based on your symptoms and health history, your doctor will likely examine you further and conduct a series of tests, which may include:

• Blood tests
• Stress test
• Electrocardiogram
• CT scan or X-ray of your chest

Low Blood Pressure Treatment

Treatment depends on if the patient is symptomatic or not, Amico says. Generally, low blood pressure without symptoms is not cause for concern, and you likely don't need further treatment.

If you're symptomatic, your health care provider will aim to treat the underlying condition causing hypotension, rather than the low blood pressure itself.

For example, low blood pressure treatment may focus on:

• Treating or managing those underlying health issues, such as diabetes or endocrine disorders
• Adjusting any medications that may be negatively affecting your blood pressure
• Increasing fluid and/or salt intake to prevent dehydration
• Making dietary adjustments and other lifestyle changes to address any nutritional deficiencies, avoiding alcohol intake and engaging in more physical activity

At-home monitoring of blood pressure is not typically part of the treatment process.

"Monitoring drives people crazy," Amico says. "There's a psychological component to every part of our disease processes that we treat. And if someone has to chronically take their blood pressure, it makes them uncomfortable."

However, if a health care professional does recommend at-home monitoring, make sure you’re following all instructions so you can stay on top of your health.

Complications of Low Blood Pressure

Untreated low blood pressure can lead to various complications, including:

• Falls and injuries: Sudden drops in blood pressure, like when standing up, can cause dizziness or fainting and lead to falls. This is particularly of concern in older adults.
• Reduced blood flow to vital organs: Prolonged cases of symptomatic low blood pressure that goes untreated may affect blood flow to vital organs, such as the brain and kidneys, leading to damage over time.
• Cognitive impairment: If blood flow to the brain is impacted over a period of time, you may experience issues with memory and overall cognitive function.
• Health condition complications: If the underlying health condition causing low blood pressure goes untreated, you may experience further health complications in ranging severity, depending on the disease.

Additionally, severe hypotension can lead to shock in rare circumstances. Hypotensive shock is a life-threatening condition that needs immediate medical attention. Causes of hypotensive shock could include severe dehydration, blood loss, heart failure or severe infections like septic shock. Symptoms may include rapid heart rate, rapid breathing, confusion, cold skin and a weak pulse.

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2024-09-18T21:53:32Z