Understanding the Dangers of Chronically Low Blood Pressure

Understanding Low Blood Pressure

Blood pressure is an important vital sign that provides critical information about your health. The pressure of blood flowing through your arteries rises and falls throughout the day. But when blood pressure dips too low, it can cause debilitating symptoms and potentially serious medical complications.

What is Considered Low Blood Pressure?

Blood pressure is recorded using two numbers - the systolic pressure (top number) indicates the force at which your heart pumps blood around your body. The diastolic pressure (bottom number) refers to the resistance to the blood flow in your blood vessels.

Normal blood pressure levels are less than 120 millimeters of mercury (mm Hg) for systolic and less than 80 mm Hg for diastolic pressure. Low blood pressure or hypotension is typically classified as:

• Systolic reading lower than 90 mm Hg
• Diastolic reading lower than 60 mm Hg

However, there is no definitive blood pressure threshold that clearly defines low blood pressure for all people. Whats considered low can vary significantly from person to person depending on age, fitness level, medical history and other factors. Even mild stages of low blood pressure like prehypotension can cause bothersome signs and symptoms for some people.

Causes of Low Blood Pressure

There are generally two types hypotension:

1. Primary hypotension - This refers to chronically low baseline blood pressure without an underlying medical issue. Its uncommon and tends to run in families.
2. Secondary hypotension - This type occurs due to an underlying health condition, medication use, dehydration, nutritional deficiency or severe infection leading blood pressure to drop. Secondary causes account for most cases of low blood pressure.

Some examples of health conditions that can induce secondary hypotension include:

• Heart problems - cardiac tamponade, heart attack, heart failure, arrhythmias, etc.
• Endocrine disorders - adrenal insufficiency, hypoglycemia, thyroid disorders
• Dehydration - from diarrhea, vomiting, excessive sweating, etc.
• Infection - septic shock, anaphylaxis
• Blood loss or hemorrhage from major trauma
• Medication side effects - diuretics, antidepressants, heart medications, etc.

Risk Factors for Hypotension

Certain individuals have increased susceptibility to low blood pressure including:

• Elderly adults over age 65
• People with heart disease or heart failure
• Endurance athletes who overtrain
• Pregnant women
• People with nutritional deficiencies - low sodium, protein, B12, iron, etc.
• Parkinsons disease patients
• Those taking certain prescription medications
• People with dysautonomia disorders

Symptoms of Low Blood Pressure

Chronic hypotension tends to cause vague, nonspecific symptoms that develop gradually over time. But significantly low blood pressure can trigger more noticeable and disruptive warning signs that warrant prompt medical care. Symptoms may include:

Lightheadedness and Dizziness

One of the hallmark signs of low BP is a sensation of lightheadedness and dizziness. This occurs as diminished blood flow to the brain leaves you feeling faint and unsteady on your feet. Episodes can come and go suddenly. Moving from a sitting to standing position often exacerbates these dizzy spells.

Fatigue and Weakness

Low blood pressure starves your cells and tissues of oxygen and vital nutrients needed for energy production. This manifests as profound fatigue, exhaustion, loss of stamina, and overall body weakness. Performing daily activities becomes noticeably more challenging.

Nausea

The drop in blood supply also deprives your digestive system of adequate circulation it needs to function properly. Feeling persistently queasy and nauseous is common when dealing with hypotension. In severe cases, vomiting and diarrhea may occur as gastrointestinal mobility declines.

Fainting (Syncope)

As low BP limits blood flow to the brain, some people lose temporary consciousness and pass out due to profound hypotension. These scary syncopal episodes tend to happen without warning when standing up suddenly or being in hot environments. Preventing falls, head trauma, and serious injury is imperative if you have a history of fainting.

Blurry Vision

Eyes depend heavily on healthy blood flow to nourish delicate optical tissues. Chronically low pressure takes a toll on your eyesight over time. Many with hypotension experience temporary vision changes like blurriness when moving from lying to standing positions as ocular perfusion pressure drops.

Confusion

Brain fog, mood changes, difficulty concentrating, and bewilderment are other neurological signs of decreased brain circulation from low BP. Reversible dementia-like effects on cognition and memory can mimic early stages of dementia diseases for some seniors with hypotension.

Chest Discomfort

While less common than the nervous system symptoms, shortness of breath, chest tightness and pain have been reported, likely from oxygen deprivation of heart and lung tissues. However, chest symptoms should be evaluated to rule out underlying cardiorespiratory disorders as the cause.

Pale, Cold Skin

Since blood flow is reduced systemically, many with chronically low pressure suffer from constantly feeling cold, clammy, pale skin as their extremities fail to receive enough warm, oxygenated blood. Poor peripheral circulation causes fingertips and toes to appear blueish and numb as well.

Dangers and Complications

While frustrating symptoms and quality of life issues pose problems for those with mild hypotension, further blood pressure drops can be catastrophic. Extremely low readings below 90/60 mm Hg correlate to higher rates of the following severe complications:

Falls and Serious Injuries

Fainting caused by precipitous blood pressure plunges leaves people susceptible to dangerous falls, head trauma, broken bones, hip fractures, subdural hematomas and other debilitating accidental injuries requiring emergency treatment and extended rehabilitation.

Acute Organ Failure

Without adequate perfusion pressure, hypotension can critically impair blood flow to vital organs provoking acute renal, liver or respiratory failure. This life-threatening shock demands ICU admission, organ support measures and potent IV medication infusions to rapidly improve BP.

Heart Attacks and Strokes

Chronically low pressure taxes the heart as it tries harder to pump blood against gravity and through constricted blood vessels. Over time, the overexertion and oxygen starvation heightens risk for myocardial infarction, arrhythmias, and congestive heart failure. Reduced cerebral blood flow also makes ischemic strokes more likely.

Seizures

The brain is incredibly sensitive to fluctuations in perfusion and oxygenation. For those prone to seizures, a sudden 30%+ drop in MAP can trigger a debilitating convulsive episode and loss of consciousness. The elderly and those with epilepsy face higher risk.

Diagnosing Low Blood Pressure

Since most only exhibit vague symptoms initially, diagnosing hypotension can be tricky without routine blood pressure monitoring. Doctors will review your symptoms, medical history, family history, medication/substance use and other factors. Diagnostic tests may include:

Orthostatic Vital Signs

One of the simplest methods for unmasking low BP is checking lying/standing blood pressure and heart rate measurements. A significant drop in pressure upon standing (e.g. > 20 mmHg) indicates impaired autonomic control of blood pressure.

Tilt Table Testing

For those with episodes of passing out, a tilt table evaluation assesses how your cardiovascular system responds to postural changes. After baseline vitals are recorded while lying flat, the table angles you upright gradually monitoring for BP/HR abnormalities.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.