Essential Tremor

What is Essential Tremor?

Tremor is an uncontrollable rhythmic shaking. It may occur in several different neurological disorders which have other associated signs or symptoms. For some people, however, their only problem is the tremor and it is not associated with any other condition. In these cases it is called idiopathic or essential tremor (ET).

While essential tremor may involve other parts of the body, the hands and head are most often affected. The shaking often begins in the dominant (writing) hand, and may spread to both hands, affecting both writing and eating. Some affected individuals also develop a quavering intonation to their speech as a result of the disorder. Essential tremor is often slowly progressive and shaking may worsen over time.

Is all tremor the same?

No. Essential tremor is most prominent with use of the hands, especially when trying to hold objects such as a coffee cup. In other types of tremor such as that which occurs with Parkinson’s disease, the tremor is often most prominent with walking or while the hands are at rest. Tremor due to disease of the cerebellum which controls coordination is most prominent when moving the arm or leg towards a specified target. These, and other tremor characteristics, can usually lead to an accurate diagnosis during examination by a doctor.

What is the cause of ET?

The cause of ET is unknown. In more than half of the cases, essential tremor is hereditary. In the group with an inherited type it is transmitted as an ‘autosomal dominant’ trait, meaning that children of an affected individual will have a 50 percent chance of also developing the disorder.

Both men and women are equally affected by essential tremor. The usual age at onset is in the 40s, but it may also occur as early at the teens. When tremor begins in the elderly, it is sometimes referred to as "senile" tremor.

What can I do about it?

Avoid stimulants such as caffeine or becoming overtired which will tend to make ET worse. If the tremor is only minor, no treatment is required. If it is more disabling, many people with essential tremor can benefit from medical treatment. Drugs such as propranolol and primidone are the mainstays of treatment. Some alternative drugs and surgical treatments are also available. Small amounts of alcohol may temporarily relieve tremor, but heavy drinking may be harmful.

Dr. R. O'Brien

------------------------------------