Overview

Postural hypotension, also known as orthostatic hypotension, is a condition where a person experiences a significant drop in blood pressure upon standing up from a sitting or lying position. This drop in blood pressure can lead to dizziness, lightheadedness, fainting, and even falls. Postural hypotension occurs when the body fails to adjust blood flow and maintain stable blood pressure during changes in posture. While occasional mild dizziness is common, persistent or severe orthostatic hypotension may indicate an underlying medical problem that requires attention.

Causes

Postural hypotension can result from a variety of causes, often involving issues with the autonomic nervous system, fluid balance, or medication side effects. Common causes include:

• Dehydration: Reduced fluid levels can lower blood volume, leading to a drop in blood pressure when standing.
• Medications: Drugs such as diuretics, blood pressure medications, antidepressants, and sedatives may cause orthostatic hypotension.
• Autonomic Nervous System Disorders: Conditions like Parkinson’s disease, multiple system atrophy, and diabetic neuropathy can impair autonomic regulation of blood pressure.
• Heart Problems: Arrhythmias, heart failure, and valve disorders can hinder the heart’s ability to maintain stable circulation.
• Prolonged Bed Rest or Immobility: Extended periods of lying down can lead to deconditioning of the circulatory system, causing postural hypotension upon standing.
• Pregnancy: Hormonal and circulatory changes during pregnancy may result in postural hypotension, particularly in the second trimester.
• Alcohol Consumption: Alcohol can cause blood vessels to dilate, increasing the risk of a blood pressure drop when standing.
• Aging: Older adults are more susceptible due to reduced baroreceptor sensitivity and medication use.

Symptoms

Symptoms of postural hypotension typically appear within seconds to minutes after standing and can range from mild to severe:

• Dizziness or Lightheadedness: The most common symptom, often described as feeling faint.
• Blurry Vision: Temporary vision changes can occur during episodes of low blood pressure.
• Fainting (Syncope): In severe cases, individuals may lose consciousness briefly after standing.
• Weakness or Fatigue: General feeling of weakness when upright.
• Nausea: Some people experience nausea during episodes.
• Confusion or Difficulty Concentrating: Reduced blood flow to the brain can impair mental clarity.
• Neck and Shoulder Pain: A dull ache around the neck and shoulders can accompany orthostatic hypotension.

Diagnosis

Diagnosis of postural hypotension involves clinical assessment, blood pressure measurements, and sometimes additional tests to identify underlying causes:

• Orthostatic Blood Pressure Measurement: Blood pressure and heart rate are measured after lying down, then again after standing for 1-3 minutes. A drop in systolic BP of 20 mm Hg or diastolic BP of 10 mm Hg confirms orthostatic hypotension.
• Medical History: A detailed history of symptoms, medication use, hydration status, and any existing medical conditions.
• Physical Examination: Assessing overall health, neurological function, and cardiovascular status.
• Blood Tests: Checking for anemia, electrolyte imbalances, and blood sugar levels.
• Electrocardiogram (ECG): To identify heart rhythm abnormalities.
• Tilt Table Test: May be used in specialized settings to assess blood pressure response to changes in posture under controlled conditions.

Treatment

Treatment of postural hypotension focuses on alleviating symptoms, addressing underlying causes, and preventing complications such as falls:

Lifestyle and Non-Pharmacological Interventions

• Increased Fluid Intake: Staying well-hydrated helps maintain blood volume.
• Salt Supplementation: In some cases, increased dietary salt (under medical supervision) can help raise blood pressure.
• Slow Position Changes: Standing up gradually from sitting or lying positions can minimize symptoms.
• Compression Stockings: These help prevent blood pooling in the legs and improve circulation.
• Elevating Head of Bed: Sleeping with the head of the bed raised can reduce overnight blood pressure drops.
• Physical Counter-Maneuvers: Leg crossing, calf muscle exercises, and abdominal tensing can increase blood pressure during standing.

Medications

• Fludrocortisone: A corticosteroid that helps expand blood volume.
• Midodrine: A vasopressor that constricts blood vessels to raise standing blood pressure.
• Pyridostigmine: May be used in some cases to improve autonomic function.
• Review and Adjustment of Medications: Reducing or stopping medications that may cause low blood pressure.

Prognosis

The prognosis of postural hypotension depends on its cause and the effectiveness of management strategies. In cases related to dehydration or medication side effects, symptoms often resolve with treatment. Chronic forms, especially due to autonomic dysfunction or neurodegenerative conditions, may require long-term management but can often be controlled with lifestyle adjustments and medications.

With proper treatment and preventive care, many individuals with postural hypotension can manage their symptoms effectively, reduce fall risk, and maintain a good quality of life. Regular follow-up with a healthcare provider is important to monitor progress and adjust treatment plans as needed.