Tremor is an unintentional, somewhat rhythmic, muscle movement involving to-and-fro movements (oscillations) of one or more parts of the body. Essential tremor (previously called benign essential tremor) is the most common form of abnormal tremor. Although it may be mild and nonprogressive in some people, in others the tremor is slowly progressive, starting on one side of the body but eventually affecting both sides.
Different Types of Essential Tremor
Many parts of the body can be affected by essential tremor including:
Hand tremor may cause problems with purposeful movements such as eating, writing, sewing, or shaving. Head tremor may be seen as a "yes-yes" or "no-no" motion. Essential tremor may be accompanied by mild gait disturbance.
Causes of Essential Tremor
About half of essential tremor cases appear to result from a genetic mutation. This form is referred to as familial tremor. It isn't clear what causes essential tremor in people without a known genetic mutation.
Research has found that changes in specific areas of the brain may contribute to essential tremor.
When Do Symptoms Occur in Essential Tremor?
Heightened emotion, stress, fever, physical exhaustion, or low blood sugar may trigger tremors or increase their severity. There may be mild degeneration in the certain parts of the cerebellum in persons with essential tremor. Onset is most common after age 40, although symptoms can appear at any age. Children of a parent who has essential tremor have up to a 50 percent chance of inheriting the condition. Essential tremor is not associated with any known pathology.
Prognosis for Essential Tremor
Although essential tremor is not life-threatening, it can make it harder to perform daily tasks and is embarrassing to some people. Tremor frequency may decrease as the person ages, but the severity may increase, affecting the person's ability to perform certain tasks or activities of daily living. In many people the tremor may be mild throughout life.
Treatments for Essential Tremor
- Deep brain stimulation (DBS)
- Physical and occupational therapy
- Eliminating tremor "triggers" such as caffeine and other stimulants from the diet is often recommended