Dysautonomia

Dysautonomia, autonomic failure, or autonomic dysfunction is a condition in which the

Diagnosis is made by functional testing of the ANS, focusing on the affected organ system. Investigations may be performed to identify underlying disease processes that may have led to the development of symptoms or autonomic neuropathy. Symptomatic treatment is available for many symptoms associated with dysautonomia, and some disease processes can be directly treated. Depending on the severity of the dysfunction, dysautonomia can range from being nearly symptomless and transient to disabling and/or life-threatening.^[11]

Signs and symptoms

The symptoms of dysautonomia, which are numerous and vary widely for each person, are due to inefficient or unbalanced efferent signals sent via both systems.^{[medical citation needed]} Symptoms in people with dysautonomia include:

Causes

Dysautonomia may be due to

In the

In addition to sometimes being a symptom of dysautonomia, anxiety can sometimes physically manifest symptoms resembling autonomic dysfunction.^[28][29][30] A thorough investigation ruling out physiological causes is crucial, but in cases where relevant tests are performed and no causes are found or symptoms do not match any known disorders, a primary anxiety disorder is possible but should not be presumed.^[31] For such patients, the anxiety sensitivity index may have better predictivity for anxiety disorders, while the Beck Anxiety Inventory may misleadingly suggest anxiety for patients with dysautonomia.^[32]

The autonomic nervous system is a component of the peripheral nervous system and comprises two branches: the sympathetic nervous system (SNS) and the parasympathetic nervous system (PSNS). The SNS controls the more active responses, such as increasing heart rate and blood pressure. The PSNS slows down the heart rate and aids digestion, for example. Symptoms typically arise from abnormal responses of either the sympathetic or parasympathetic systems based on situation or environment.^[5][35][25]

Diagnosis

Diagnosis of dysautonomia depends on the overall function of three autonomic functions—cardiovagal, adrenergic, and sudomotor. A diagnosis should at a minimum include measurements of blood pressure and heart rate while lying flat and after at least three minutes of standing. The best way to make a diagnosis includes a range of testing, notably an autonomic reflex screen, tilt table test, and testing of the sudomotor response (ESC, QSART or thermoregulatory sweat test).^[36]

Additional tests and examinations to diagnose dysautonomia include:

Tests to elucidate the cause of dysautonomia can include:

• Evaluation for acute (intermittent) porphyria^[1]
• Evaluation of cerebrospinal fluid by lumbar puncture^[1] for infectious/ inflammatory diseases
• Evaluation of nerve conduction study for autonomic neuropathy
• Evaluation of brain and spinal magnetic resonance imaging for myelopathy, stroke and multiple system atrophy
• Evaluation of MIBG myocardial scintigraphy and DaT scan for Parkinson's disease, dementia with Lewy bodies and pure autonomic failure

Vegetative-vascular dystonia

Particularly in the Russian literature,

A similar form of this disorder has been historically noticed in various wars, including the Crimean War and American Civil War, and among British troops who colonized India. This disorder was called "irritable heart syndrome" (Da Costa's syndrome) in 1871 by American physician Jacob DaCosta.^[39]

Management

Treatment of dysautonomia can be difficult; since it is made up of many different symptoms, a combination of drug therapies is often required to manage individual symptomatic complaints. In the case of autoimmune neuropathy, treatment with immunomodulatory therapies is done. If

In contrast to orthostatic hypotension (OH) in which neurodegenerative diseases might underlie, postural orthostatic tachycardia syndrome (POTS) in which psychiatric diseases might underlie responds to psychiatric intervention/ medication, or shows spontaneous remission. ^[43][44]

Prognosis

The prognosis of dysautonomia depends on several factors; people with chronic, progressive, generalized dysautonomia in the setting of central nervous system degeneration such as Parkinson's disease or multiple system atrophy generally have poorer long-term prognoses. Dysautonomia can be fatal due to

• autonomic neuropathy
• Dopamine beta hydroxylase deficiency
• Familial dysautonomia
• Reflex syncope
• Postural orthostatic tachycardia syndrome
• Orthostatic intolerance

References

Further reading

Scholia has a profile for Dysautonomia (Dysautonomia).

• Brading A (1999). The autonomic nervous system and its effectors. Oxford: Blackwell Science.
  ISBN 978-0-632-02624-1
  .
• Goldstein D (2016). Principles of Autonomic Medicine (PDF) (free online version ed.). Bethesda, Maryland: National Institute of Neurological Disorders and Stroke, National Institutes of Health.
  ISBN 978-0-8247-0408-7
  .
• Jänig W (2008). Integrative action of the autonomic nervous system : neurobiology of homeostasis (Digitally printed version. ed.). Cambridge: Cambridge University Press.
  ISBN 978-0-521-06754-6
  .
• Lara A, Damasceno DD, Pires R, Gros R, Gomes ER, Gavioli M, Lima RF, Guimarães D, Lima P, Bueno CR, Vasconcelos A, Roman-Campos D, Menezes CA, Sirvente RA, Salemi VM, Mady C, Caron MG, Ferreira AJ, Brum PC, Resende RR, Cruz JS, Gomez MV, Prado VF, de Almeida AP, Prado MA, Guatimosim S (April 2010). "Dysautonomia due to reduced cholinergic neurotransmission causes cardiac remodeling and heart failure". Molecular and Cellular Biology. 30 (7): 1746–56.
  PMID 20123977
  .
• Schiffer RB, Rao SM, Fogel BS (2003-01-01). Neuropsychiatry. Lippincott Williams & Wilkins.
  ISBN 978-0-7817-2655-9
  .