Essential tremor

Essential tremor is a neurological (nervous system) disorder which causes involuntary shaking or trembling of particular parts of the body, usually the head and hands. Sometimes the voice is affected, making it sound shaky.

The tremors typically worsen when the hands are being used (kinetic or intention tremor), and reduce significantly or stop altogether when the hands are resting. For some people, the condition worsens if they hold their bodies in certain positions (postural or intention tremor).

Generally speaking, essential tremor gradually gets worse over time and with advancing age. The cause is unknown and there is no cure, although medication and surgery may help. Older people are most susceptible, but anyone of any age can develop essential tremor – a person can even be born with it. Essential tremor and Parkinson’s disease are different disorders.

Symptoms of essential tremor

The symptoms of essential tremor include:

• affects the voluntary muscles (the muscles that you can consciously move)
• head nodding, if the head is affected
• shaky, quivering voice, if the larynx (voice box) is affected
• a small, rapid tremor
• tremor that is exacerbated by activity or movement
• tremor that eases when the body part is at rest
• tremor that stops when the person is asleep
• worsening with age
• hands, head and voice are most commonly affected
• other body parts may become affected over time, including the arms and eyelids (the legs are rarely affected).

Essential tremor is not Parkinson’s disease

Essential tremor and Parkinson’s disease are different conditions.

Essential tremor is characterised by shaking when movement starts, which can continue or worsen during movement. The symptoms of Parkinson’s disease include:

• involuntary tremor when you are not moving
• muscle stiffness
• slowness of movement
• ‘freezing’.

Parkinson’s disease is caused by a lack of supply of the brain chemical dopamine, which is necessary for smooth and controlled muscular movement.

Cause of essential tremor

Essential tremor is the most common type of tremor, and affects more people than Parkinson’s disease. Some estimates suggest that around 1 in 5 people over the age of 65 years is affected.

There is no known cause, but a genetic link is strongly suspected. Each child of a person with essential tremor has a 50% chance of inheriting the disorder themselves. If a person with essential tremor has other affected family members, then the disorder is called ‘familial tremor’. Tremor can occur as a side effect of some medications or exposure to contaminants in the environment (E.g. Mercury).

Factors affecting essential tremors

Certain factors are known to worsen the condition, including:

• emotional stress
• physical activity
• caffeinated drinks
• fatigue and insufficient sleep
• alcohol consumption and withdrawl (in some people).

Effects of essential tremor on quality of life

Uncontrollable shaking can reduce a person’s quality of life in many ways, including:

• difficulties with everyday activities, such as writing, getting dressed or eating
• irritation and stress caused by the inability to control the affected body part
• social embarrassment
• increased fatigue.

Diagnosis of essential tremor

Essential tremor is diagnosed using a number of tests, including:

• medical history
• physical examination
• electromyography (EMG) test to check the electrical activity of muscles
• tests to rule out other causes – such as x-rays, blood tests, magnetic resonance imaging (MRI) and computed tomography (CT) scans.

Treatment of essential tremor

There is no cure for essential tremor. Treatment aims to suppress the involuntary movements. To identify the best treatment, you should consult with a Neurologist. Treatments can include:

• avoidance of known triggers, such as alcohol or caffeine
• stress management techniques
• some medications used to treat other medical conditions, such as heart disease (beta blockers) and epilepsy (anticonvulsants) – these medications have been helpful in some cases
• other medications, including tranquillisers
• deep brain stimulation, a surgically implanted device that helps to short-circuit the impulses or brain waves causing the tremor
• brain surgery to alter the part of the brain causing the tremor has been successful in some cases
• MRI guided focused ultrasound (a treatment for some people with essential tremor, but it’s not covered by Medicare in Australia)
• regular monitoring and observation – if the tremor is mild and doesn’t stop the person from performing their usual activities, this may be the only treatment.

In some cases, alcohol may reduce the tremors. However, this is not a recommended treatment, because long-term consumption of alcohol has significant health risks.

Where to get help

• Your GP (doctor)
• Referral to a neurologist
• Fight Parkinson’s Tel. 1800 644 189