Spring, 2014
- Description:
- Essential tremor is the most common movement disorder among adults. Primarily affecting people over the age of 40, essential tremor is a neurological disorder that causes rhythmic shaking or trembling, most frequently of the hands (one or both), but it may affect any part of the body (especially the head, voice, arms or legs). The well-known actress Katherine Hepburn had this condition. In her later years, it affected her voice, head and movement.
- Cause:
- Sometimes confused with Parkinson’s Disease, essential tremor is not related to or caused by other diseases. Approximately half of essential tremor cases appear to result from a genetic mutation. This type is referred to as familial tremor. The cause of essential tremor in people without this genetic mutation remains undetermined, though research indicates that changes in specific areas of the brain may be the culprit.
- Symptoms:
- Usually beginning gradually, symptoms worsen with movement. In the hands, trembling becomes apparent during daily activities such as attempting to hold a glass steady while drinking, tying shoe laces, shaving, brushing teeth, applying make-up, and eating. When it affects the head, it may result in a "yes-yes" or "no-no" motion. Stress, fatigue, caffeine or extreme temperatures can exacerbate symptoms.
- Progression:
- Usually mild and gradual in nature, essential tremor does progress and can become more severe.
- Treatment:
- If essential tremor is severe enough to interfere with one’s work or daily activities, treatment may be necessary. Adaptive techniques and tools such as using heavier glasses and utensils, wrist weights and wide grip pens may be sufficient in controlling mild symptoms. Physical or occupational therapy may be recommended to improve muscle strength, control and coordination. A treatment for high blood pressure, beta blockers, can help relieve tremors for some people, but may not be an option for those with asthma and certain heart problems. Anti-seizure medications may also be effective for people who don’t respond to or can’t take beta-blockers. For those whose symptoms worsen with anxiety, tranquilizers may be prescribed. Primarily used for head and voice tremors, injections of botulinum toxins may help for up to 3 months at a time. For those with severe, disabling symptoms that don’t improve with therapy or medication, a surgical procedure, deep brain stimulation (DBS) has been found to be very effective. With DBS, a thin electrode is inserted into the thalamus, the portion of the brain responsible for the tremors, and a pacemaker-like device (neurostimulator) is implanted in the chest. Under the skin, a wire connects the probe with the device. The device transmits painless electrical pulses that interrupt the signals from the thalamus.
| Essential tremor | Parkinson’s disease | Parts of body affected | Hands, head, voice | Hands, legs, chin and other body parts |
|---|---|---|
| Occurrence of hand tremor | With movement/active use of hands | Most frequently occurs when hands are at rest at one’s sides or on one’s lap |
| Other symptoms | Occasional development of other neurological signs and symptoms, such as an unsteady gait (ataxia) | Also associated with a stooped posture, slow movement, shuffling gait, and non-motor symptoms |
| 1 | Chuang WL, Huang YZ, Lu CS, and Chen RS. Reduced cortical plasticity and GABAergic modulation in essential tremor. Mov Disord. 2014. doi: 10.1002/mds.25809. [Epub ahead of print] Abstract available at: http://www.ncbi.nlm.nih.gov/pubmed/24449142. Accessed 1/24/2014. |
| 2 | Mayo Clinic Website. Diseases and Conditions. Essential Tremor. Available at: http://www.mayoclinic.org/diseases-conditions/essential-tremor. Accessed 1/24/2014. |
| 3 | USC Website. Center for Deep Brain Stimulation: Essential Tremor. Available at: http://dbs.usc.edu/disease-information/essential-tremor. Accessed 1/25/2014. |
This article originally appeared on page 3 of the Spring, 2014 PMDF newsletter.