What is Dysautonomia?

Dysautonomia is a dysfunction of the autonomic nervous system. It can be either a breakdown or a failure of the autonomic nervous system. Dysautonomia can be a primary condition or a secondary condition to a disease such as diabetes or hypothyroidism. Dysautonomia is an umbrella term for multiple syndromes/disorders, such as Orthostatic Intolerance, Postural Orthostatic Tachycardia Syndrome (POTS), Neurocardiogenic Hypotension/Syncope, Pure Autonomic Failure, and Multiple System Atrophy.

What is the Autonomic Nervous System?

The autonomic nervous system (ANS) is the wiring and circuitry that controls most of the body's involuntary (automatic) functions. It also controls the body's "fight or flight" response to stimuli. Because the ANS controls almost all of the involuntary function of the body, almost all body systems can be affected by this disorder. Some of the systems the ANS controls are cardiovascular, respiratory, gastrointestinal, and endocrine function. Therefore, a dysfunction of the autonomic nervous system, or dysautonomia, is much more than "just" a jump in heart rate when someone stands up causing them to get dizzy or faint. This is the thought process of many people who have heard of the disorder, but do not understand the depth of how it affects a person's whole life.

Types of Dysautonomia

Orthostatic Intolerance (OI)

A condition where the body is unable effectively adjust to an upright posture. The body is does not react appropriately to the force of gravity, and this causes a chain reaction of side effects. (See list of symptoms in Part 2)

Postural Orthostatic Tachycardia Syndrome (POTS)

A syndrome where a persons heart rate (HR) increases 30 or more beats per minute or over 120 beats per minute when they stand up, and they feel symptomatic to the sudden increase in heart rate (See list of symptoms in Part 2). This HR increase can happen in all people every once and a while, for example when dehydrated, but with POTS it is a regular occurrence. POTS is a form of Orthostatic Intolerance that causes a substantial increase in HR upon standing and the associated symptoms of this HR increase. Much of the symptoms of POTS are thought to be due an imbalanced and inaccurate ANS response controlling the blood flow that a person needs after having an adjustment in their posture. So, a person's blood flow is not responding to the body's needs and there will be too much pooling of blood in the legs, and areas like the brain will not be getting enough blood. This decrease in amount of blood and oxygen to the brain is what causes people to become dizzy/lightheaded and possibly faint.

Neurocardiogenic Hypotension/Syncope (NCH/NCS)

Is when there is a misfiring in the circuitry responding to position changes of the body, and the persons BP plummets upon standing. People that have Neurocardiogenic Hypotension/Syncope often faint, nearly faint, or are symptomatic when they stand up. The lower blood pressure means that less oxygenated blood is going to the brain, when the body does not react appropriately to the change in position. Proper precautions can be taken to limit a person's symptoms and occurrence of fainting, but fainting and symptoms can still occur upon standing. With Neurocardiogenic Syncope (NCS) the person does not necessarily have a high HR upon standing like those with POTS.

Pure Autonomic Failure (PAF)

Is a relatively rare degenerative disorder of the autonomic nervous system. It affects men more than women, and normally presents in mid to late life. It can affect anything that the ANS controls. Many of the symptoms are the same as the other disorders, but are more severe and/or progressive. Once diagnosed most people can live 20 or more years after a diagnosis of Pure Autonomic Failure.

Multiple System Atrophy (MSA)

Is a relatively rare condition where there is severe autonomic nervous system failure, along with impairment in other neurological systems (cerebellar, extrapyramidal, neuromuscular, or pyramidal). It occurs more often in men, and presents on average at approximately 60 years old. MSA can be diagnosed by neuronal loss and gliosis being found in multiple areas of the brain. MSA is more severe than PAF, and patient's life expectancy is often less than 10 years.