Orthostatic Hypotension

Excerpt

Orthostatic hypotension, also known as postural hypotension, is defined as a sudden drop in blood pressure that occurs upon standing from a sitting or supine position. This condition significantly impacts quality of life and increases the risk of falls, cardiovascular disease, dementia, depression, and mortality. Clinically, orthostatic hypotension is defined as a sustained drop in systolic blood pressure (SBP) of at least 20 mm Hg or diastolic blood pressure of 10 mm Hg within 3 minutes of standing after being supine for at least 5 minutes or positioned at a 60° angle on a tilt table. This sudden drop in blood pressure is typically caused by autonomic reflex failure, volume depletion, cardiovascular disease, neuropathy, or adverse medication effects.

Symptoms on presentation are often related to cerebral hypoperfusion, although some patients may remain asymptomatic. Orthostatic hypotension is associated with a high rate of morbidity and mortality, primarily due to frequent falls and multiple hospital admissions. Additionally, the condition is closely linked to other causes of morbidity, such as cardiovascular and neurodegenerative diseases.

Orthostatic hypotension occurs due to an inadequate physiological response to postural changes. This condition can be either symptomatic or asymptomatic and may present as acute or chronic. In younger patients, neurogenic causes are typically responsible for orthostatic hypotension unless volume depletion is present. In older patients, age-related orthostatic hypotension, cardiovascular causes, and neuropathy are more commonly observed. Orthostatic hypotension becomes more prevalent with age, affecting about 1 in 5 individuals aged 60 or older. Postprandial hypotension is also common in older patients and those with autonomic failure, where SBP drops by at least 20 mm Hg within 2 hours after having a meal.