NIH - Tremor (Medical Encyclopedia) "Disorders with tremor as the primary symptom include: • Familial tremor (runs in families) • Essential tremor (no known cause) • Drug-induced tremor (drugs known to induce tremor include valproic acid, lithium, and cyclosporine). Parkinson's disease and other illnesses may cause tremors in addition to other symptoms. Certain medical problems such as hyperthyroidism or Wilson's disease may cause tremors. Symptoms • Tremors - May be occasional (sporadic), temporary (episodic) or occurring at intervals (intermittent) - May affect the head, hands, arms, eyelids, or other muscles - May not affect both sides of the body equally • A shaking or quivering sound to voice • Head nodding • Tremors that worsen with voluntary movement or emotional stress • Tremors that disappear during sleep."

NIH - NINDS Tremor Information Page “What is Tremor? Tremor is an unintentional, somewhat rhythmic, muscle movement involving to-and-fro movements of one or more parts of the body. Most tremors occur in the hands, although they can also affect the arms, head, face, vocal cords, trunk, and legs. Sometimes tremor is a symptom of another neurological disorder, but the most common form occurs in otherwise healthy people. Some forms of tremor are inherited and run in families, while others have no known cause. Excessive alcohol consumption or alcohol withdrawal can kill certain nerve cells, resulting in tremor, especially in the hand. Other causes include an overactive thyroid and the use of certain drugs. Tremor may occur at any age but is most common in middle-aged and older persons. Essential tremor (sometimes called benign essential tremor) is the most common of the more than 20 types of tremor.The hands are most often affected but the head, voice, tongue, legs, and trunk may also be involved. Head tremor may be seen as a "yes-yes" or "no-no" motion. Onset is most common after age 40, although symptoms can appear at any age. Parkinsonian tremor is caused by damage to structures within the brain that control movement. The tremor is classically seen as a "pill-rolling" action of the hands but may also affect the chin, lips, legs, and trunk. Dystonic tremor occurs in individuals of all ages who are affected by dystonia, a movement disorder in which sustained involuntary muscle contractions cause twisting motions or painful postures or positions. “ NIH - Hand tremor (Medical Encyclopedia) http://www.nlm.nih.gov/medlineplus/ency/article/003192.htm “A tremor is an involuntary movement or shaking of any body part (even your head or voice may be involved). It is often most noticeable in your hands. There are three main types of tremors: • Resting or static tremors occur when your hand or affected body part is at rest. • Kinetic tremors, including intention tremors, occur when you are moving your hand or affected body part and disappear at rest. • Postural tremors occur when you are holding your hand or affected body part in a particular position for a period of time. … Essential tremor is common in older people. Essential tremor is rarely present when the hands are not being used. It becomes most apparent when the affected person is trying to do something, like reaching for an object or writing. It is not caused by an underlying disease. Another common type of tremor is called familial tremor which, as the name implies, tend to run in families. Both essential and familial tremors may be suppressed by drinking alcohol. This is a useful fact for making the diagnosis, but alcohol is not a desirable treatment. Causes: Tremors may be caused by: • Too much coffee or other caffeinated drink • Excessive alcohol consumption, alcoholism, or alcohol withdrawal • Stress, anxiety, or fatigue -- these can cause a postural tremor • Normal aging • A variety of drugs and prescription medicines • Low blood sugar • Parkinson's disease -- this is the classic cause of a resting tremor and is often accompanied by slowness of movement, muscle rigidity, and an abnormal gait • Multiple sclerosis -- can cause an intention tremor • Over active thyroid -- can cause a postural tremor … What to Expect at Your Office Visit: Your doctor will perform a physical examination, including a detailed neurologic examination. The following medical history questions may help your doctor evaluate the cause of your tremors: • Is your tremor regular or irregular? • Does it occur with activity, at rest, or when you have been holding your hand (or other body part) in a particular position for a long time? • Are the movements small (fine) or large (coarse)? • Are both hands affected? To the same degree on both sides? • Are other body parts affected, including your voice or head? • Does the tremor impair your ability to use your hands or other body parts? • Does emotional stress or excitement make it worse? • Does drinking an alcoholic beverage make the tremor better or worse? • Do you have any other symptoms? “

NIH - Essential tremor (Medical Encyclopedia) “Essential tremor is a nerve disorder in which tremors (shakes) occur in a person who is moving or trying to move and no cause can be identified. … Essential tremor is the most common form of abnormal tremor. Although the cause is unknown, new research shows that the part of the brain called the cerebellum does not appear to work correctly in patients with essential tremor. The cerebellum is the part of the brain that coordinates muscle movements. Essential tremor is a relatively benign condition, affecting movement or voice quality, but with no other effects. It involves a rhythmic, moderately rapid tremor of voluntary muscles. Purposeful movements may make the tremors worse, while avoiding hand movements may make the tremors go away completely. People with essential tremors may have trouble holding or using small objects, such as silverware or a pen. Over time, the tremors may affect the hands, arms, head, voice box, eyelids, or other muscles. An essential tremor rarely involves the legs or feet. There are several different types of essential tremor, including young-onset essential tremor and essential tremor with head tremor. These types differ in their response to treatment. If an essential tremor occurs in more than one member of a family, it is called a familial tremor. It appears that genes may play a role in the development of essential tremors. Not only have the tremors been shown to be passed down through families, but an identical twin (who shares the same genes) of a person with essential tremor is twice as likely as a fraternal twin (who has different genes) to have essential tremor. Since some identical twins do not share this condition, environmental factors must also play a role. Essential tremors can occur at any age but are most common in people older than 65. Symptoms: The tremors: • May be occasional (sporadic), temporary (episodic) or occurring at intervals (intermittent) • Occur at a rate of about 6 to 10 oscillations per second • May affect the head, hands, arms, eyelids, voice • Less commonly affect the legs and feet • May not affect both sides of the body equally • Worsen with voluntary movement or emotional stress • Disappear during sleep • Typically improve with alcohol “

NHS - Tremor (essential) “Essential tremor is shaking or trembling of part of your body, which you can't control and that lasts for at least a few seconds. It is most common in the hands, the feet, the head, the jaw and the tongue, but it can occur in any part of your body. We all experience a very fine tremor all the time we are awake as our body goes about its daily functions. This will be the slight tremor you see when you put out your hands for example. It is known as physiological tremor and is normal. From time to time, this everyday level of tremor can increase so that it becomes more noticeable. Occasional noticeable tremor is common in people of all ages, and very common in older people, and does not necessarily mean that you have any sort of medical condition. It can be caused by tiredness, stress, anxiety, or anger. A raised level of adrenalin in your body, which can happen when you become excited or angry, can often cause a noticeable tremor. Essential tremor is where the normal trembling of your muscles is regularly exaggerated so that it becomes frequently noticeable. The tremor may be so exaggerated that it becomes difficult for you to do normal activities. Essential tremor is made worse by the same factors that exaggerate normal tremor, such as when you are stressed, anxious, or angry, or if you do strenuous activity, drink caffeine or take some prescribed medicine. … Essential tremor often begins gradually. Sometimes it appears during your teens, then goes away for years, only to return later in life. More often, symptoms begin in mid to late life. Most people with essential tremor experience a trembling, up-and-down movement of their hands. Less commonly, your arms, head, tongue and eyelids may be affected. Your voice box (larynx) can also be affected and this may lead to your voice sounding shaky or quavering. Occasionally, essential tremor can cause tremors in your legs or feet. Your symptoms may not affect both sides of your body equally. Tremors usually occur only when you make controlled movements, such as when you try picking up an object or drinking a glass of water. Actions requiring fine motor skills - like writing or using small tools - may be especially difficult. You may find that things like eating, putting on makeup, or shaving all become difficult. Tremors usually disappear when your body is at rest or when you are asleep. If you are tired, anxious, hot or cold, your symptoms are likely to become worse. Some people have relatively mild symptoms while others find that their tremors become more severe over time. … There is no specific test that can diagnose essential tremor, so it is usually diagnosed only once your GP has ruled out other possible causes for your symptoms. You may have tests to rule out causes such as thyroid disease, Parkinson's disease and drug side effects. The tests may include X-rays, urine tests, blood tests, MRI scans (magnetic resonance imaging scan) and CT scans (computerised tomography scan). As well as tests to rule out other causes, your GP will physically examine you to check for tremor when you move. They will check your medical history and that of your immediate family to see whether essential tremor runs in your family. Your GP may also ask you to have an EMG test (electromyography test) to check the electrical activity of your muscles.”

Highlighted Articles

Essential Tremor: A Clinical Review (2008) “Essential tremor (ET) is a common neurologic movement disorder. Estimates suggest that ET may be as much as 10 to 20 times as prevalent as Parkinson's disease (PD), affecting from 5 million up to as many as 10 million people in the United States. In the past, the condition was often referred to as "benign essential tremor." However, many experts consider use of the term "benign" unfortunate, since it may inappropriately minimize the impact of ET on disability, handicap, and quality of life (QOL). … Rest tremor occurs when muscle is not voluntarily activated, whereas action tremor is present with voluntary contraction of muscle. Subtypes of action tremor include postural, kinetic, and isometric tremor. Postural tremor is present while voluntarily maintaining a position against gravity. Kinetic tremor may occur during any form of voluntary movement. Intention or terminal tremor refers to exacerbation of kinetic tremor toward the end of a goal-directed movement. Isometric tremor is present during voluntary muscle contraction without movement.”

Risk of incident dementia in essential tremor: A population-based study. (Mov Disord. 2007) " … ET cases with tremor onset after age 65 years were twice as likely to develop incident dementia than were controls …"

Mediterranean Diet and Essential Tremor (Neuroepidemiology 2007) "Conclusions: Compared to controls, ET cases adhered less to MeDi. The gradual reduction in ET odds with higher MeDi adherence tertiles suggests a possible dose-response effect."

Tremor in multiple sclerosis. (J Neurol. 2007) "Tremor is estimated to occur in about 25 to 60 percent of patients with multiple sclerosis (MS). This symptom, which can be severely disabling and embarrassing for patients, is difficult to manage."

Essential tremor--the most common movement disorder in older people. (Age Ageing. 2006) "Essential tremor (ET) affects approximately 4% of the population above 65 years of age. The traditional view that ET is a familial mono-symptomatic disorder with a benign prognosis has recently been challenged, as it is now known to be a progressive and clinically heterogeneous condition with sporadic and familial forms."

Study of possible factors associated with age of onset in essential tremor. (Mov Disord. 2006) "Ninety-one percent of cases with onset before age 20 years had a family history of tremor. Age of onset was not associated with other variables of interest … The familial form of ET is characterized by an earlier age of onset than the sporadic form."

Internet Sites

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