Rarely diagnosed orthostatic tremor has no cause, cure

Dear Dr. Roach: In 2013, I complained to my internist about severe shaking in my legs and hands. He referred me to a neurologist, who diagnosed me with a rare disease: primary orthostatic tremor. Most doctors don’t know about this condition, which was first described in 1984. I am told there is no known cause nor cure for POT, that very little research being done and that it is expected to get worse with age.

I was exposed to Agent Orange in Vietnam, and my internist thought this was a possible cause of my condition.

R.W.N.

Primary orthostatic tremor probably was first described in 1970, and named in 1984. The tremor is present mainly in the legs and trunk, and is not present when walking, sitting or lying down. Some people have arm symptoms as well. The problem is thought to arise from the cerebellum, or brainstem. It is often misdiagnosed.

I was unable to find any association between POT and exposure to Agent Orange.

One treatment, as first described in the original paper, is clonazepam, although it is by no means a cure. Gabapentin also has been effective for some. As far as research, the University of Nebraska and others have been doing research into this disorder.

A great website for more information is at orthostatictremor.org. Dear Dr. Roach: What is the average cardiac ejection fraction for a healthy 77-year-old? What about a fit and hale athlete?

M.K. The ejection fraction is the proportion of blood, usually expressed as a percentage, that is ejected from the left ventricle into the aorta during each cardiac cycle.

The normal range is 50 to 75 per cent. Between 40 and 50 per cent is considered borderline, and 40 per cent and below is considered reduced.

People with low ejection fraction and symptoms of fatigue or breathlessness have what is is now called heart failure with reduced ejection fraction.

It is possible to have heart failure with normal (or preserved) ejection fraction. Ejection fractions above 75 per cent are called hyperdynamic, and suggest hypertrophic cardiomyopathy.

Some elite athletes have enlargement of the left ventricle, so that when the heart is tested at rest, it may appear that the ejection fraction is abnormally low.

However, the hearts of these elite athletes are very, very good, capable of sending a great deal of blood to the body so they can continue to exercise at high levels at which others would become exhausted. Only 11 per cent of Tour de France participants have hearts like this.

Outside of athletes, and especially in older adults, lower ejection fractions tend to predict higher rates of heart failure and mortality, especially in people who had reduced ejection fraction to begin with (lower than 45 per cent).

I hope it’s clear that the ejection fraction by itself can be misleading under certain circumstances, and needs to be interpreted with the whole patient in mind. Dr. Roach Writes: I asked for input on how my U.S. readers found ways how to reduce costs of medications. The majority of readers found that purchasing out of the country, especially Canada but also India, significantly (on average, by 70 per cent) reduced the cost of prescription drugs. A few people had good experiences with the sites I asked about, blinkhealth.com and goodrx.com.

Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu