Consider Tremor Along With Other Symptoms
“Parkinson’s reputation is that it is a tremor disease, and that’s how you can identify it across a crowded room,” says Rebecca Gilbert, MD, PhD, chief scientific officer for the American Parkinson Disease Association in New York City. Although tremors bring people to diagnosis in many cases, defining the condition as a tremor disease may have done patients a disservice over the years because there are more severe symptoms that people struggle with. Tremor is just the one that people can see, according to Dr. Gilbert. “Many think if you don’t have a tremor everything is fine,” she says. “That isn’t true.” Over time, other disease features, such as cognitive problems, psychosis, blood pressure irregularities, depression, and lack of desire to do things, can be more devastating. James Beck, PhD, chief scientific officer with the Parkinson’s Foundation, also cautions that tremor may not be the first distinguishing feature. “A person may notice a slowness of movement called bradykinesia,” he says. “Or someone may be walking down the street and one arm doesn’t swing. These symptoms may appear before tremor.” While focusing only on tremor may not be advisable, understanding this abnormal movement and treatment options may help patients improve their quality of life.
What Is a Tremor and What Makes It Different With Parkinson’s?
Tremor is an uncontrollable, rhythmic muscle contraction that triggers quivering in one or more parts of the body. It often occurs in hands, arms, or legs but can also affect the head, neck, or torso. This shaking may appear in sporadic spells or continue constantly. The National Institute of Neurological Disorders and Stroke says that age is a risk factor — middle-aged and older adults are more likely to experience tremors.
What Is a Resting Tremor?
A Parkinson’s tremor differs from most other types of tremor because it is a “resting tremor.” It happens most often when a body part is relaxed rather than in motion. For a Parkinson’s patient, a hand may quiver when resting in a lap or when holding a utensil to the mouth while eating. Most tremors are “action tremors” where the shaking happens when a person moves their muscles. These may occur when holding arms outstretched, holding a heavy item in one position, or reaching slowly and purposefully toward an object.
Types of Parkinson’s Tremors
Quivering in these parts of the body can be signs of Parkinson’s:
Finger Twitching Commonly seen among patients in the early stages of the disease, this symptom is also called a “pill-rolling” tremor because the fingers and hand appear to be rolling a pill-sized object.Jaw Tremors This movement in the jaw may resemble a slow shivering and disappear while eating or talking. In some cases, the teeth chatter. Patients may chew gum to stop the trembling.Foot Tremors This shakiness may appear while resting, lying down, or dangling the feet. It stops when standing and walking. It can also extend beyond the feet and cause the whole leg to vibrate.Tongue Tremors Although far less reported than other types of tremor, quivering in tongue can be a revealing manifestation of Parkinson’s, according to an article published in December 2015 in the journal Movement Disorders Clinical Practice. The shaking can also appear in the chin, lips, and face.
While these types of tremors can help doctor identify Parkinson’s, about 30 percent of patients do not have these movements, per prior research. “Those people who do not have a resting tremor may not get a diagnosis immediately,” says Gilbert. “If doctors don’t see it, they won’t necessarily think a person has Parkinson’s.”
Parkinson’s Tremors vs. Essential Tremors
Because they can be similar to Parkinson’s tremors, essential tremors are often confused as symptoms of the disease. Just as with Parkinson’s, essential tremor can cause uncontrollable rhythmic shaking in different parts of the body. Up to 10 million people are affected by this common nervous system disorder. While genetics and environment likely play a role in essential tremor, the cause is unknown, according to the U.S. National Library of Medicine. Essential tremors in the hands or arms can be distinct from Parkinson’s because they typically happen when the hands are in use. “The essential tremor can get really bad when you’re using your limb — when drinking or eating soup, for example,” says Gilbert. “The Parkinson’s tremor is usually not as disabling whereas the essential tremor can be life-altering.” The shaking from an essential tremor typically improves when using both hands to bring a cup to the mouth but the same action can amplify the tremor in Parkinson’s, according to Gilbert. Dr. Beck points out that an essential tremor may be faster than a Parkinson’s tremor, which tends to be milder. A difference can often be seen in a person’s handwriting. Those with essential tremor tend to have more unsteady and wavy writing, whereas Parkinson’s patients are more apt to display micrographia, or abnormally small handwriting. “They have low amplitude movement so their writing gets smaller and smaller to a point where it can be barely legible,” he says. Primarily, essential tremor involves hands, head, and voice, notes the Mayo Clinic, whereas Parkinson’s can be more likely to affect other parts of the body. Parkinson’s patients can develop stooped posture, slow movement, and a shuffling gait — symptoms that don’t typically appear in those with essential tremor. Note, too, that some people can have both Parkinson’s tremor as well as essential tremor.
Can Tremors Be Treated?
Parkinson’s disease cannot be cured, but a range of therapies are available to help reduce the tremors.
Medication for Tremors
Parkinson’s patients have low levels of dopamine, a chemical that helps nerve cells in the brain transmit signals. Drugs that ease tremor along with problems in walking and movement either increase dopamine in the body or provide a substitute for the lack of the chemical. These include:
Carbidopa and Levodopa Levodopa is generally recognized as the most effective drug to treat Parkinson’s symptoms. It is a natural chemical that can enter the brain and convert into dopamine, and carbidopa is a chemical that helps more of the levodopa get to the brain. Some common brands are Sinemet, Parcopa, Stalevo, Rytary, and Duopa.Dopamine Agonists These agents stimulate dopamine receptors.They may not be as strong as carbidopa-levodopa but they also may be less likely to cause dyskinesias (abnormal, involuntary body movements). Dopamine agonists include Mirapex (pramipexole), Requip (ropinirole), and Neupro (rotigotine).MAO-B Inhibitors Previous research has shown that these drugs can help prevent the breakdown of dopamine in the brain. They include Eldepryl and Zelapar (selegiline), Azilect (rasagiline), and Xadago (safinamide).Anticholinergics These drugs are specifically designed to control Parkinson’s tremors. A common brand is Cogentin (benztropine).Catechol O-Methyltransferase (COMT) Inhibitors These drugs can prolong levodopa therapy. Comtan (entacapone) is a popular COMT inhibitor.Amantadine Sold under the brand name Gocovri, amantadine is a prescription that may be given early in the disease progression to help with dyskinesia.
Treating Tremors With Medication Is Difficult
Gilbert estimates that about 70 percent of patients get tremor relief from medication. Also, as the disease progresses, the medication may become less effective. “The brain is changing as a result of the disease so medications may not work like they used to at the beginning of the disease,” says Beck. For some patients, taking higher doses of medication can help, but these larger amounts can produce side effects. “It can be a double-edged sword,” says Beck. “The result of taking higher doses can lead to dyskinesia, where arms move about in an uncontrolled fashion.” The American Parkinson’s Disease Foundation points out that although a medication may not be improving tremor, it could be providing other benefits with stiffness and mobility.
Deep Brain Stimulation Surgery
When medication becomes less effective, patients may explore deep brain stimulation surgery. The treatment involves an invasive operation, but the procedure has been shown to be about 80 to 90 percent effective in eliminating tremor completely or almost completely. The surgery can reduce the need to take a burdensome amount of medication and improve quality of life. Electrodes are placed deep in the brain and connected to a battery-powered neurostimulator device, similar to a pacemaker, which is implanted in the chest. The device sends impulses to the brain that help regulate brain activity. “There are many options to treat tremors. But it’s a very complex process in terms of evaluating the patient and figuring out which one is going to be the best tolerated and most effective,” says Gilbert.
