Chronic hypotension

Chronic hypotension is a persistently low blood pressure (BP) that may result in inadequate end-organ perfusion. Definitions of chronic hypotension vary by clinical context; comparing the blood pressure with the patient's baseline and evaluating the overall clinical picture are key. Although often idiopathic, secondary causes include medications, heart failure, cirrhosis, adrenal insufficiency, and Parkinson disease. Affected individuals may present with fatigue, dizziness, and syncope. Initial investigations to identify a possible underlying cause include orthostatic vital signs, blood tests, and an electrocardiogram; further studies may include ambulatory blood pressure monitoring and transthoracic echocardiogram (TTE). Management primarily involves reducing or stopping contributing medications and treating identified underlying causes. Asymptomatic patients generally have a good prognosis and only require reassurance. Symptomatic patients are managed with approaches used for orthostatic hypotension (e.g., increased salt and fluid intake, compression garments).

• Hypotension: BP below an individual's expected baseline, typically associated with symptoms of tissue or organ hypoperfusion; definitions vary by clinical context and are based on changes from baseline or absolute parameters. ^[1]
• Chronic hypotension ^[1]
  • BP persistently below an individual’s expected baseline ^[2][3]
  • May be symptomatic if it results in tissue or organ hypoperfusion

This article covers hypotension with a chronic duration. For acute hypotension, see "Shock"; for intermittent hypotension, see "Causes of syncope."

• Idiopathic: also referred to as constitutional or essential hypotension; clinical significance is debated ^[2]
• Secondary, e.g.: ^[2]
  • Cirrhosis ^[4]
  • Heart failure
  • Adrenal insufficiency
  • Medication (e.g., nitroglycerin, antihypertensives)
  • Dehydration and hypovolemia (typically manifest acutely)
  • Pregnancy ^[5]
  • Neurogenic (e.g., Parkinson disease, spinal cord injury)

Individuals with chronic hypotension due to identifiable secondary causes frequently have concomitant orthostatic hypotension. ^[2]

Focused history ^[2]

• Symptoms of hypotension (e.g., fatigue, dizziness, presyncope or syncope) ^[6]
  • Onset, duration, and severity
  • Timing and triggers (e.g., postprandial hypotension, situational syncope)
• Symptoms suggestive of the underlying cause (e.g., dyspnea, bleeding)
• Past medical history
  • Chronic illnesses (e.g., cardiac disease, diabetes mellitus, Parkinson disease)
  • Vasoactive medications (e.g., nitroglycerin, antihypertensives)

Focused examination ^[2][7]

• Clinical signs of end-organ hypoperfusion: altered mental status, oliguria, prolonged capillary refill time, cold or mottled extremities
• Vital signs
  • Blood pressure measurement confirmed with an appropriately sized cuff ^[8]
  • Heart rate and rhythm (e.g., cardiac arrhythmias)
  • Temperature (e.g., fever in sepsis)
  • Orthostatic vital signs
• Volume status assessment: clinical features of dehydration and hypovolemia
• Cardiovascular examination: signs of heart failure, murmurs
• Respiratory examination: crackles (e.g., pulmonary edema), asymmetric breath sounds (e.g., pneumothorax)
• Abdominal examination: flank pain, pulsatile mass (e.g., abdominal aortic aneurysm)

Compare blood pressure with the patient’s baseline and assess the overall clinical picture, as some individuals have chronically low blood pressure. ^[1]

Diagnostic evaluation is guided by the clinical picture and aimed at identifying an underlying cause. For evaluation of acute hypotension, see "Diagnostics in shock."

• Initial studies ^[2]
  • CBC with differential: to assess for anemia
  • BMP: to assess for electrolyte abnormalities
  • Morning cortisol and ACTH: to assess for adrenal insufficiency
  • ECG: for cardiac arrhythmias, ischemia
  • Hemoglobin A1c or fasting plasma glucose: to assess for diabetes
  • Pregnancy test: indicated in individuals who can become pregnant
• Additional studies: based on clinical suspicion ^[2][9]
  • Diagnostics for cirrhosis (e.g., liver ultrasound, liver elastography)
  • Diagnostics for heart failure (e.g., TTE, NT-proBNP)
  • Holter monitoring for suspected arrhythmia
  • Ambulatory blood pressure monitoring to assess BP during daily activities
  • Tests for autonomic dysfunction (e.g., tilt table test, heart rate variability)
  • Diagnostics in Parkinson disease

Treatment of symptomatic chronic idiopathic hypotension is not well-established; evidence is limited and practice varies.

• Reduce or stop contributing medications.
• Treat any identified underlying conditions.
• For general symptoms of hypoperfusion (e.g., fatigue, cognitive impairment), management as for orthostatic hypotension may be considered.
  • Nonpharmacological management of orthostatic hypotension (e.g., adequate hydration, increased salt intake, compression garments)
  • Pharmacological treatment (e.g., midodrine, fludrocortisone)
• Asymptomatic patients require reassurance only.

Asymptomatic chronic hypotension without associated orthostatic hypotension generally does not require treatment. ^[2][15]