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Why Did the Yellow Wiggle Fall Down?

MedpageToday
If you have a toddler, you know who The Wiggles are.

For those of you who don't, are a children's music group formed in Sydney, Australia in 1991. The original members, which included Anthony Field, Phillip Wilcher, Murray Cook, Greg Page and Jeff Fatt, are known as much for their color-coded clothing as their kid-friendly rock songs.

Greg Page, the Wiggle in the yellow shirt, retired in 2006 because of a mysterious condition that caused him to faint and lose feeling in his limbs. After an extensive work-up, the diagnosis of Orthostatic Intolerance (OI) was made. OI is a cardiovascular syndrome that can be treated with medication and lifestyle changes. Page was ecstatic:
Just knowing that what I had had a name, and it wasn't terminal, and it could be treated was wonderful. I feel like I'm getting a second chance."
And now, Page is doing much better, so much so that he is rejoining the group and going back on tour. His physician, Dr. Susan Corcoran, told
Simple measures have been effective in helping his condition, but he'll need to be careful with the rigors of the tour.

What is Orthostatic Intolerance?

Orthostatic Intolerance (OI), sometimes called orthostatic hypotension, refers to a group of conditions which is defined as "the development of symptoms during upright standing relieved by recumbency."

The effects of gravity cause blood-pooling in the legs upon standing. Between 700 and 750 ml of blood can be shifted away from the thorax. An intact, complex interaction of physical, neurologic, humoral, vascular and blood volume factors are necessary to prevent a significant drop in blood pressure and brain perfusion.

The autonomic nervous system plays an important role in these interactions, causing vasoconstriction of the vessels in the lower extremities and thereby preventing a large drop in blood pressure.

It is estimated that over 500,000 people are affected by orthostatic intolerance. OI affects more women four times more often than men; patients are usually under the age of 35 when diagnosed.

For clinical purposes, those with orthostatic intolerance are divided two categories: acute and chronic OI.

Many healthy people occasionally suffer from acute orthostatic hypotension, which is usually manifested by syncope or pre-syncope. It can be triggered by upright posture for long periods of time, a warm environment, an emotionally stressful event, or too little fluid and salt intake. A classic example of acute OI is a soldier who faints after standing rigidly at attention for an extended period of time. Of course, not all syncope is orthostatic, and cardiac, pulmonary, and vasovagal factors should all be considered in a particular patient.

Those with chronic OI have symptoms nearly every day. These symptoms can include:
  • Lightheadedness
  • Headache
  • Fatigue
  • Altered vision (blurred vision, "white outs," black outs)
  • Weakness
  • Difficulty breathing or swallowing
  • Tremulousness
  • Sweating
  • Anxiety
  • Heart palpitations, as the heart races to compensate for the falling blood pressure
  • Exercise intolerance
Many patients with chronic OI also have what is called POTS, Postural Tachycardia Syndrome, where the symptoms of OI are associated with tachycardia. Both of these disorders are considered forms of dysautonomia.

, a researcher at the Johns Hopkins University School of Medicine, OI and other forms of dysautonomia are common in other conditions like MS and Parkinson’s; it also occurs in less well-studied conditions like Ehlers-Danlos Syndrome, Marfan syndrome and Shy-Drager Syndrome.

Interestingly, up to 97% of those who have are thought to have some form of OI.

How is OI Diagnosed and Treated?

OI is notoriously difficult to diagnose. Many patients have gone undiagnosed or misdiagnosed and either untreated or treated for other disorders.

The 4 standard forms of orthostatic testing are (1) standing, (2) head-upright tilt (HUT) table testing, (3) the use of lower body negative pressure (LBNP), and (4) combined HUT and LBNP. The details of these tests can be found in an excellent by Dr. Julian Stewart.

It should be noted that certain patients with OI, especially those with (CFS), may have a , meaning that heart rate and blood pressure changes don't develop for many minutes after standing. This makes the standard in-office test for acute orthostatic hypotension inaccurate for making the diagnosis.

The first line of treatment is typically :
  • Increase fluids and salt (drinking more than eight cups of fluids each day)
  • Tilt the head of the bed up slightly
  • Wear compression garments (such as support hose, girdles or abdominal binders)
  • Learn to avoid and cope with things that can make OI worse (such as standing in long lines, being in warm environments and eating large, heavy meals)
Medications can be used to treat more severe cases. Dr. Stewart categorizes the most commonly used:
  1. Agents that expand blood volume, such as fludrocortisone and erythropoietin, sometimes are useful by reducing the degree of thoracic hypovolemia.
  2. Vasoconstrictive agents, such as
  3. Selective serotonin reuptake inhibitors (SSRI) have met with some success in treating CFS and orthostatic intolerance.
  4. Mestinon () an acetylcholinesterase inhibitor has met with considerable success in the treatment of POTS and has often been used in combination with midodrine.

For more information: click to go to the Resounding Health Casebook on the topic.