Orthostatic hypotension

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Orthostatic hypotension, also known as postural hypotension,^[2] is a medical condition wherein a person's blood pressure drops when standing up or sitting down. Primary orthostatic hypotension is also often referred to as neurogenic orthostatic hypotension.^[3] The drop in blood pressure may be sudden (vasovagal orthostatic hypotension), within 3 minutes (classic orthostatic hypotension) or gradual (delayed orthostatic hypotension).^[4] It is defined as a fall in systolic blood pressure of at least 20 mmHg or diastolic blood pressure of at least 10 mmHg after 3 minutes of standing. It occurs predominantly by delayed (or absent) constriction of the lower body blood vessels, which is normally required to maintain adequate blood pressure when changing the position to standing. As a result, blood pools in the blood vessels of the legs for a longer period, and less is returned to the heart, thereby leading to a reduced cardiac output and inadequate blood flow to the brain.

Orthostatic hypotension
Other names	Orthostasis, postural, positional hypotension, neurogenic orthostatic hypotension
Specialty	Cardiology, neurology
Symptoms	Symptoms that are worse when sitting or standing and improve when lying down, including lightheadedness, vertigo, tinnitus, slurred speech, confusion, coathanger pain in neck and shoulders, grayed or blurred vision, severe fatigue, fainting or near fainting
Complications	Cumulative brain damage, sudden death from falls
Diagnostic method	In-office (lay down for at least 20 minutes, take BP; stand for 3 minutes, take BP), or tilt-table testing by an autonomic specialist
Treatment	Identify and treat causes (medications, dehydration), midodrine, compression garments, bed tilting
Prognosis	Depends on frequency, severity, and underlying cause; neurogenic orthostatic hypotension is a chronic, debilitating, and often progressively fatal condition^[1]

Very mild occasional orthostatic hypotension is common and can occur briefly in anyone, although it is prevalent in particular among the elderly and those with known low blood pressure. Severe drops in blood pressure can lead to fainting, with a possibility of injury. Moderate drops in blood pressure can cause confusion/inattention, delirium, and episodes of ataxia. Chronic orthostatic hypotension is associated with cerebral hypoperfusion that may accelerate the pathophysiology of dementia.^[5] Whether it is a causative factor in dementia is unclear.^[6]

The numerous possible causes for orthostatic hypotension include certain medications (e.g. alpha blockers), autonomic neuropathy, decreased blood volume, multiple system atrophy, and age-related blood-vessel stiffness.

Apart from addressing the underlying cause, orthostatic hypotension may be treated with a recommendation to increase salt and water intake (to increase the blood volume), wearing compression stockings, and sometimes medication (fludrocortisone, midodrine, or others). Salt loading (dramatic increases in salt intake) must be supervised by a doctor, as this can cause severe neurological problems if done too aggressively.

Signs and symptoms

Orthostatic hypotension is characterized by symptoms that occur after standing (from lying or sitting), particularly when done rapidly. Many report lightheadedness (a feeling that one might be about to faint), sometimes severe, or even actual fainting with associated fall risk.^[7][8][9] With chronic orthostatic hypotension, the condition and its effects may worsen even as fainting and many other symptoms become less frequent. Generalized weakness or tiredness may also occur. Some also report difficulty concentrating, blurred vision, tremulousness, vertigo, anxiety, palpitations (awareness of the heartbeat), unsteadiness, feeling sweaty or clammy, and sometimes nausea. A person may look pale.^[10] Some people may experience severe orthostatic hypotension with the only symptoms being confusion or extreme fatigue. Chronic severe orthostatic hypotension may present as fluctuating cognition/delirium.^{[citation needed]} Women who are pregnant are also susceptible to orthostatic hypotension.^{[11][12][13][14]}

Associated diseases

The disorder may be associated with Addison's disease, atherosclerosis (build-up of fatty deposits in the arteries), diabetes, pheochromocytoma, porphyria,^[15] and certain neurological disorders, including autoimmune autonomic ganglionopathy, multiple system atrophy, and other forms of dysautonomia. It is also associated with Ehlers–Danlos syndrome and anorexia nervosa. It is also present in many patients with Parkinson's disease or Lewy body dementias resulting from sympathetic denervation of the heart or as a side effect of dopaminomimetic therapy. This rarely leads to fainting unless the person has developed true autonomic failure or has an unrelated heart problem.^{[citation needed]}

Another disease, dopamine beta hydroxylase deficiency, also thought to be underdiagnosed, causes loss of sympathetic noradrenergic function and is characterized by low or extremely low levels of norepinephrine, but an excess of dopamine.^[16]

Quadriplegics and paraplegics also might experience these symptoms due to multiple systems' inability to maintain normal blood pressure and blood flow to the upper part of the body.^{[citation needed]}

Causes

Some causes of orthostatic hypotension include neurodegenerative disorders, low blood volume (e.g. caused by dehydration, bleeding, or the use of diuretics), drugs that cause vasodilation, other types of drugs (notably, narcotics and marijuana), discontinuation of vasoconstrictors, prolonged bed rest (immobility), significant recent weight loss, anemia,^[17] vitamin B₁₂ deficiency, or recent bariatric surgery.^[18]

Medication

 

Tetrahydrocannabinol

Orthostatic hypotension can be a side effect of certain antidepressants, such as tricyclics^[19] or monoamine oxidase inhibitors (MAOIs).^[20] Marijuana and tetrahydrocannabinol can on occasion produce marked orthostatic hypotension.^[21] Alcohol can potentiate orthostatic hypotension to the point of syncope.^[22] Orthostatic hypotension can also be a side effect of alpha-1 blockers (alpha₁ adrenergic blocking agents). Alpha₁ blockers inhibit vasoconstriction normally initiated by the baroreceptor reflex upon postural change and the subsequent drop in pressure.^[23] Other antihypertensive medications may also cause orthostatic hypotension, in addition to anticholinergics, dopaminergic drugs, opiates and psychoactive medications.^[24]

Other factors

Patients prone to orthostatic hypotension are the elderly, post partum mothers, and those having been on bed rest. People with anorexia nervosa and bulimia nervosa often develop orthostatic hypotension as a common side effect. Consuming alcohol may also lead to orthostatic hypotension due to its dehydrating effects.^{[citation needed]}

Mechanism

Orthostatic hypotension happens when gravity causes blood to pool in the lower extremities, which in turn compromises venous return, resulting in decreased cardiac output and subsequent lowering of arterial pressure. For example, changing from a lying position to standing loses about 700 ml of blood from the thorax, with a decrease in systolic and diastolic blood pressures.^[25] The overall effect is insufficient blood perfusion in the upper part of the body.^{[citation needed]}

Normally, a series of cardiac, vascular, neurologic, muscular, and neurohumoral responses occurs quickly so the blood pressure does not fall very much. One response is a vasoconstriction (baroreceptor reflex), pressing the blood up into the body again. (Often, this mechanism is exaggerated and is why diastolic blood pressure is a bit higher when a person is standing up, compared to a person in the horizontal position.) Therefore, some factor that inhibits one of these responses and causes a greater than normal fall in blood pressure is required. Such factors include low blood volume, diseases, and medications.^{[citation needed]}

Diagnosis

Orthostatic hypotension can be confirmed by measuring a person's blood pressure after lying flat for 5 minutes, then 1 minute after standing, and 3 minutes after standing.^[26] Orthostatic hypotension is defined as a fall in systolic blood pressure of at least 20 mmHg or the diastolic blood pressure of at least 10 mmHg between the supine reading and the upright reading. Also, the heart rate should be measured for both positions. A significant increase in heart rate from supine to standing may indicate a compensatory effort by the heart to maintain cardiac output. A related syndrome, postural orthostatic tachycardia syndrome (POTS), is diagnosed when at least a 30 bpm increase in heart rate occurs with little or no change in blood pressure. A tilt table test may also be performed.^[27]

Definition

Orthostatic hypotension (or postural hypotension) is a drop in blood pressure upon standing. One definition (AAFP) calls for a systolic blood pressure decrease of at least 20 mm Hg or a diastolic blood pressure decrease of at least 10 mm Hg within 3 minutes of standing.^[28] A common first symptom is lightheadedness upon standing, possibly followed by more severe symptoms: narrowing or loss of vision, dizziness, weakness, and even syncope (fainting).^{[citation needed]}

Subcategories

Orthostatic hypotension can be subcategorized into three groups – initial, classic, and delayed.^[29][30][31]

Initial orthostatic hypotension is frequently characterized by a systolic blood pressure decrease of ≥40 mmHg or diastolic blood pressure decrease of ≥20 mmHg within 15 seconds of standing.^[29] Blood pressure then spontaneously and rapidly returns to normal, so the period of hypotension and symptoms is short (<30 s).^[29] Only continuous beat-to-beat BP measurement during an active standing-up maneuver can document this condition.^[29]

Classic orthostatic hypotension is frequently characterized by a systolic blood pressure decrease of ≥20 mmHg or diastolic blood pressure decrease of ≥10 mmHg between 30 seconds and 3 min of standing.^[30]

Delayed orthostatic hypotension is frequently characterized by a sustained systolic blood pressure decrease of ≥20 mm Hg or a sustained diastolic blood pressure decrease ≥of 10 mm Hg beyond 3 minutes of standing or upright tilt table testing.^[31]

Management

Lifestyle changes

Apart from treating underlying reversible causes (e.g., stopping or reducing certain medications, treating autoimmune causes), several measures can improve the symptoms of orthostatic hypotension and prevent episodes of syncope (fainting). Even small increases in the blood pressure may be sufficient to maintain blood flow to the brain on standing.^[30]

In dysautonomic patients who do not have a diagnosis of high blood pressure, drinking 2–3 liters of fluid a day and taking 10 g of salt can improve symptoms, by maximizing the amount of fluid in the bloodstream.^[30] Another strategy is keeping the head of the bed slightly elevated. This reduces the return of fluid from the limbs to the kidneys at night, thereby reducing nighttime urine production and maintaining fluid in the circulation.^[30] Various measures can be used to improve the return of blood to the heart; the wearing of compression stockings and exercises ("physical counterpressure maneuvers" or PCMs) can be undertaken just before standing up (e.g., leg crossing and squatting).^[30]

Medications

The medication midodrine can benefit people with orthostatic hypotension,^[30][32] The main side effect is piloerection ("goose bumps").^[32] Fludrocortisone is also used, although based on more limited evidence.^[30]

Droxidopa has been shown to be effective as well,^[33] with few, mostly mild side effects reported.^[34]

A number of other measures have slight evidence to support their use – indomethacin, fluoxetine, dopamine antagonists, metoclopramide, domperidone, monoamine oxidase inhibitors with tyramine (can produce severe hypertension), oxilofrine, potassium chloride, and yohimbine.^[35]

Other

Robotic devices, such as the Erigo medical device, have been proven to help orthostatic hypotension in some patients. These machines adjust a patient's position from 0 degrees to 90 degrees in progressive increments, allowing the blood pressure to adjust more slowly.^[36]

Prognosis

Orthostatic hypotension may cause accidental falls.^[9] It is also linked to an increased risk of cardiovascular disease, heart failure, and stroke.^[37][24] Also, observational data suggest that orthostatic hypotension in middle age increases the risk of eventual dementia and reduced cognitive function.^[38]

See also

• Orthostatic hypertension
• Orthostatic intolerance
• Vasovagal response

References

1. Arnold AC, Raj SR (December 2017). "Orthostatic Hypotension: A Practical Approach to Investigation and Management". The Canadian Journal of Cardiology. 33 (12): 1725–1728. doi:10.1016/j.cjca.2017.05.007. PMC 5693784. PMID 28807522.
2. "at Dorland's Medical Dictionary
3. Ricci F, De Caterina R, Fedorowski A (August 2015). "Orthostatic Hypotension: Epidemiology, Prognosis, and Treatment". Journal of the American College of Cardiology. 66 (7): 848–860. doi:10.1016/j.jacc.2015.06.1084. PMID 26271068.
4. "Orthostatic Hypotension Information Page | National Institute of Neurological Disorders and Stroke". www.ninds.nih.gov. Retrieved 2017-03-26.
5. Hase Y, Polvikoski TM, Firbank MJ, Craggs LJ, Hawthorne E, Platten C, et al. (January 2020). "Small vessel disease pathological changes in neurodegenerative and vascular dementias concomitant with autonomic dysfunction". Brain Pathology. 30 (1): 191–202. doi:10.1111/bpa.12769. PMC 8018165. PMID 31357238. S2CID 19310855.
6. Sambati L, Calandra-Buonaura G, Poda R, Guaraldi P, Cortelli P (June 2014). "Orthostatic hypotension and cognitive impairment: a dangerous association?". Neurological Sciences. 35 (6): 951–957. doi:10.1007/s10072-014-1686-8. PMID 24590841. S2CID 19310855.
7. Shaw BH, Borrel D, Sabbaghan K, Kum C, Yang Y, Robinovitch SN, Claydon VE (March 2019). "Relationships between orthostatic hypotension, frailty, falling and mortality in elderly care home residents". BMC Geriatrics. 19 (1): 80. doi:10.1186/s12877-019-1082-6. PMC 6415493. PMID 30866845.
8. Mol A, Bui Hoang PT, Sharmin S, Reijnierse EM, van Wezel RJ, Meskers CG, Maier AB (May 2019). "Orthostatic Hypotension and Falls in Older Adults: A Systematic Review and Meta-analysis" (PDF). Journal of the American Medical Directors Association. 20 (5): 589–597.e5. doi:10.1016/j.jamda.2018.11.003. hdl:1871.1/3c04fc8f-8520-4a7e-bf5c-8ba541a61acb. PMID 30583909. S2CID 57898094.
9. Romero-Ortuno R, Cogan L, Foran T, Kenny RA, Fan CW (April 2011). "Continuous noninvasive orthostatic blood pressure measurements and their relationship with orthostatic intolerance, falls, and frailty in older people". Journal of the American Geriatrics Society. 59 (4): 655–665. doi:10.1111/j.1532-5415.2011.03352.x. hdl:2262/57382. PMID 21438868. S2CID 31596763.
10. Kasper DL, Fauci AS, Hauser SL, Longo DL, James JL, Loscalzo J (2015). Harrison's principles of internal medicine. Vol. 2 (19th ed.). New York: McGraw-Hill Medical Publishing Division. p. 2639. ISBN 978-0-07-180215-4.
11. Miyake Y, Ohnishi M, Fujii TK, Yamamoto T, Yoneda C, Takahashi S, Ichimaru Y (2002-01-01). "The effects of postural changes of baroreflex gain in normal and hypertensive pregnancies". Clinical and Experimental Hypertension. 24 (1–2): 23–31. doi:10.1081/CEH-100108712. PMID 11848166. S2CID 777855.
12. Lucini D, Mela GS, Malliani A, Pagani M (November 2002). "Impairment in cardiac autonomic regulation preceding arterial hypertension in humans: insights from spectral analysis of beat-by-beat cardiovascular variability". Circulation. 106 (21): 2673–2679. doi:10.1161/01.CIR.0000039106.89299.AB. PMID 12438292. S2CID 9826957.
13. Easterling TR, Schmucker BC, Benedetti TJ (October 1988). "The hemodynamic effects of orthostatic stress during pregnancy". Obstetrics and Gynecology. 72 (4): 550–552. PMID 3419734.
14. Brooks VL, Dampney RA, Heesch CM (August 2010). "Pregnancy and the endocrine regulation of the baroreceptor reflex". American Journal of Physiology. Regulatory, Integrative and Comparative Physiology. 299 (2): R439–R451. doi:10.1152/ajpregu.00059.2010. PMC 2928618. PMID 20504907.
15. Sim M, Hudon R (October 1979). "Acute intermittent porphyria associated with postural hypotension". Canadian Medical Association Journal. 121 (7): 845–846. PMC 1704473. PMID 497968.
16. Robertson D, Garland EM (September 2003). "Dopamine Beta-Hydroxylase Deficiency". In Adam MP, Ardinger HH, Pagon RA, Wallace SE, Bean LJ, Stephens K, Amemiya A (eds.). GeneReviews. University of Washington, Seattle. PMID 20301647 – via NCBI Bookshelf.
17. "What Causes Hypotension? -". National Heart, Lung, and Blood Institute (NHLBI). U.S. National Institutes of Health. Retrieved 27 March 2017.
18. Christou GA, Kiortsis DN (March 2017). "The effects of body weight status on orthostatic intolerance and predisposition to noncardiac syncope". Obesity Reviews. 18 (3): 370–379. doi:10.1111/obr.12501. PMID 28112481. S2CID 46498296.
19. Jiang W, Davidson JR (November 2005). "Antidepressant therapy in patients with ischemic heart disease". American Heart Journal. 150 (5): 871–881. doi:10.1016/j.ahj.2005.01.041. PMID 16290952.
20. Delini-Stula A, Baier D, Kohnen R, Laux G, Philipp M, Scholz HJ (March 1999). "Undesirable blood pressure changes under naturalistic treatment with moclobemide, a reversible MAO-A inhibitor – results of the drug utilization observation studies". Pharmacopsychiatry. 32 (2): 61–67. doi:10.1055/s-2007-979193. PMID 10333164. S2CID 260241107.
21. Jones RT (November 2002). "Cardiovascular system effects of marijuana". Journal of Clinical Pharmacology. 42 (S1): 58S–63S. doi:10.1002/j.1552-4604.2002.tb06004.x. PMID 12412837. S2CID 12193532.
22. Narkiewicz K, Cooley RL, Somers VK (February 2000). "Alcohol potentiates orthostatic hypotension : implications for alcohol-related syncope". Circulation. 101 (4): 398–402. doi:10.1161/01.CIR.101.4.398. PMID 10653831.
23. Shea MJ, Thompson AD. "Orthostatic Hypotension". Merck Manual.
24. Kim, Michael J.; Farrell, Jennifer (January 2022). "Orthostatic Hypotension: A Practical Approach". American Family Physician. 105 (1): 39–49. ISSN 1532-0650. PMID 35029940.
25. Idiopathic Orthostatic Hypotension and other Autonomic Failure Syndromes at eMedicine
26. "Measurement of lying and standing blood pressure: A brief guide for clinical staff". RCP London. 2017-01-13. Retrieved 2019-09-23.
27. Natale A, Akhtar M, Jazayeri M, Dhala A, Blanck Z, Deshpande S, et al. (July 1995). "Provocation of hypotension during head-up tilt testing in subjects with no history of syncope or presyncope". Circulation. 92 (1): 54–58. doi:10.1161/01.CIR.92.1.54. PMID 7788917.
28. Bradley JG, Davis KA (December 2003). "Orthostatic hypotension". American Family Physician. 68 (12): 2393–2398. PMID 14705758.
29. Wieling W, Krediet CT, van Dijk N, Linzer M, Tschakovsky ME (February 2007). "Initial orthostatic hypotension: review of a forgotten condition". Clinical Science. 112 (3): 157–165. doi:10.1042/CS20060091. PMID 17199559.
30. Moya A, Sutton R, Ammirati F, Blanc JJ, Brignole M, Dahm JB, et al. (November 2009). "Guidelines for the diagnosis and management of syncope (version 2009)". European Heart Journal. 30 (21): 2631–2671. doi:10.1093/eurheartj/ehp298. PMC 3295536. PMID 19713422.
31. Gibbons CH, Freeman R (July 2006). "Delayed orthostatic hypotension: a frequent cause of orthostatic intolerance". Neurology. 67 (1): 28–32. doi:10.1212/01.wnl.0000223828.28215.0b. PMID 16832073. S2CID 33902650.
32. Izcovich A, González Malla C, Manzotti M, Catalano HN, Guyatt G (September 2014). "Midodrine for orthostatic hypotension and recurrent reflex syncope: A systematic review". Neurology. 83 (13): 1170–1177. doi:10.1212/WNL.0000000000000815. PMID 25150287. S2CID 5439767.
33. Mathias CJ (March 2008). "L-dihydroxyphenylserine (Droxidopa) in the treatment of orthostatic hypotension: the European experience". Clinical Autonomic Research. 18 (Supplement 1): 25–29. doi:10.1007/s10286-007-1005-z. PMID 18368304. S2CID 29861644.
34. Kaufmann H, Freeman R, Biaggioni I, Low P, Pedder S, Hewitt LA, et al. (July 2014). "Droxidopa for neurogenic orthostatic hypotension: a randomized, placebo-controlled, phase 3 trial". Neurology. 83 (4): 328–335. doi:10.1212/WNL.0000000000000615. PMC 4115605. PMID 24944260.
35. Logan IC, Witham MD (September 2012). "Efficacy of treatments for orthostatic hypotension: a systematic review". Age and Ageing. 41 (5): 587–594. doi:10.1093/ageing/afs061. PMID 22591985.
36. Sorbera C, Portaro S, Cimino V, Leo A, Accorinti M, Silvestri G, et al. (Apr–Jun 2019). "ERIGO: a possible strategy to treat orthostatic hypotension in progressive supranuclear palsy? A feasibility study". Functional Neurology. 34 (2): 93–97. PMID 31556389.
37. Ricci F, Fedorowski A, Radico F, Romanello M, Tatasciore A, Di Nicola M, et al. (July 2015). "Cardiovascular morbidity and mortality related to orthostatic hypotension: a meta-analysis of prospective observational studies". European Heart Journal. 36 (25): 1609–1617. doi:10.1093/eurheartj/ehv093. PMID 25852216.
38. Rawlings A, Juraschek S, Heiss G, Hughes T, Meyer M, Selvin E, et al. (7 March 2017). "Abstract 28: Orthostatic Hypotension is Associated With 20-year Cognitive Decline and Incident Dementia: the Atherosclerosis Risk in Communities (ARIC) Study". Circulation. 135 (suppl_1). doi:10.1161/circ.135.suppl_1.28.

External links

• Orthostatic hypotension at Curlie
• Postural hypotension : what it is and how to manage it – Centers for Disease Control and Prevention