The Outs and Ins of OI

Managing CFS, Understanding CFS | 19. Jun, 2011 by | 68 Comments

By K. Kimberly McCleary, President & CEO

On Friday we posted a link to an article in TIME magazine’s Healthland section, “Tip for Insomniacs: Cool Your Head to Fall Asleep,” on our Facebook page.

“When Buysse’s group [at University of Pittsburgh] gave 12 insomniacs a cap to wear that contained circulating water at cool temperatures, they were able to get them to fall asleep almost as easily as people without sleep disorders: using the caps, the insomniacs took about 13 minutes to fall asleep, compared with 16 minutes for the healthy controls, and they slept for 89% of the time they were in bed, which was similar to the amount of time the controls spent asleep.”

HEAT_WAVE_072605-300x225The comments posted in response to the article were split between readers who expressed problems with sleep (common in CFS) and readers who found different temperatures to affect their symptoms (also common in CFS). Of those who commented about temperature, most had trouble in warm environments. While many people with CFS are knowledgeable about a condition called “orthostatic intolerance” (OI) that often co-occurs with CFS, every time we post something about OI, we hear from at least one person who wasn’t aware of it, but reports that it explains a lot of the “weird” symptoms they experience. With summer heat on its way, and because treatment of OI through medication, dietary and postural approaches can provide symptom relief, it can be an important part of managing CFS — especially when temperatures rise.

Some Basics

OI is the development of a set of characteristic symptoms while standing or sitting upright. It has been associated with CFS in both adults and children.

The 1986 definition of myalgic encephalomyelitis (M.E.) by Melvin A. Ramsey, M.D., includes “orthostatic tachycardia” as one of the accompanying features. Rowe-300x225The first research study connecting OI and CFS was published in the Lancet in 1995, by Peter Rowe, MD, and associates at Johns Hopkins University, who identified a type of OI called neurally mediated hypotension (NMH) in CFS patients. Since 1995, scientists have learned much more about the broader problem of OI in CFS. It is now thought that many CFS patients (up to 97 percent in some studies) have some form of OI and it seems to be a particular problem in young people with CFS.

Dr. Rowe presented a webinar about OI and its management on Sept. 1, 2010, as part of the Association’s 2010 Webinar Series. The recording and his slides provide an excellent overview. He also shared his clinic’s written material about OI and medications, postural and dietary complements to comprehensive management of OI.

Types of OI

There are many types of OI. When you round up experts who study the autonomic nervous system (as we did at one of our research symposia in the year 2000), they have trouble agreeing on the names and definitions for the various types of OI. (Does that sound familiar?) 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 Ehler’s Danlos Syndrome, Marfan syndrome and Shy-Drager Syndrome. So, it’s not unique to or diagnostic of CFS.

At least two specific forms of OI have been linked with CFS in multiple research studies: NMH and postural orthostatic tachycardia syndrome (POTS):

  • NMH is a precipitous drop (at least 20-25 mm Hg) in systolic blood pressure when standing. The blood pressure drop is accompanied or preceded by an increase in symptoms.
  • POTS is a rapid increase in heart rate (pulse) of more than 30 beats per minute (bpm) from baseline, or to more than 120 bpm total, during the first 10 minutes of standing. It is also known as chronic orthostatic intolerance, or COI.

OI is easier to recognize (and treat) in individuals who have normal or low resting blood pressure. But, it’s also possible for OI to be a problem for people who have high blood pressure. As you can see from the description above, forms of OI describe blood pressure control and heart rate control problems that are provoked by upright posture.

Symptoms of OIThe blood pressure and heart rate changes in NMH and POTS are accompanied by orthostatic symptoms such as lightheadedness, dizziness, nausea, fatigue, tremors, breathing or swallowing difficulties, headache, visual disturbances, sweating and pallor. Many patients develop swollen, bluish legs, providing evidence of blood pooling in the lower part of the body. These symptoms can become worse or be provoked more quickly in warm temperatures or hot indoor environments like saunas. (This last part is what many people who commented on the cooling cap story reported.)

OI should be better understood by primary doctors than it probably is, but if you suspect you might have OI, start there. You may have to see a specialist for a formal evaluation. Expect an extra challenge from your doctor(s) if you haven’t ever fainted; many doctors only associate OI with forms that involve “syncope” or fainting. You can learn more about testing for and the underlying pathophysiology of OI here

(Update: For more specific information about the possible confusion between symptoms of OI and anxiety prompted by a question arising from this post, please see my post, “Is It Anxiety or OI?”

OI Treatment

Effective treatment for NMH and POTS in CFS must be individualized. In general, treatment for POTS and NMH helps greatly to alleviate some symptoms, but rarely fully resolves the CFS. For some people, it makes a huge difference.

According to the experts, the first line of treatment should be non-medical interventions, such as increasing fluids and salt, tilting the head of the bed up a few degrees, wearing compression garments (such as support hose, girdles or abdominal binders), and learning 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). Here are some of the top “tips” for managing OI compiled from various articles and our readers:

If these are not effective, doctors may introduce pharmaceutical treatments such as fludrocortisone (Florinef) to treat low blood volume; and vasoconstrictor medications, including methylphenidate (Ritalin), dextroamphetamine (Dexedrine) and midodrine (ProAmatine) to treat blood pooling (Inderal or Tenormin); and sometimes drugs to block the release or effect of epinephrine and norepinephrine. Selective serotonin reuptake inhibitors (SSRIs) have been used with some success in patients with POTS, and one randomized trial has demonstrated the efficacy of paroxetine (Paxil) for those with recurrent syncope due to NMH.


Figure from Dr. Rowe’s webinar presentation

Intravenous saline can help reduce symptoms, especially following HUT or other acute exacerbations of symptoms. Common syncope treatments beta-blockers and clonidine may be less effective in POTS and may reflect different causes for POTS and simple fainting. You can learn more about the medications used to treat OI.

OI and its connection to CFS remains a vigorous area of research and the Solve ME/CFS Initiative has supported several studies looking at different mechanisms for the autonomic nervous system problems that are common in CFS. You can hear Dr. Marvin Medow of New York Medical College describe his Association-funded study on our webinar, Go With the Flow. You can also use the tag cloud (to the right) to search for other articles about orthostatic intolerance here on Research1st.

Like CFS itself, managing OI generally requires a combination of pharmacological and non-pharmacological therapies. Small changes can have positive effects over time, especially if they become routine. Whether it’s a cooling cap or finding the right beta blocker, it may be worth exploring.

K. Kimberly McCleary has served as the Association’s chief staff executive since 1991.

(Updated by the author on June 20, 2011.)

June 19, 2011