Around 500,000 people in the United States have Parkinson's disease, a neurological disorder that affects movement, according to the National Institute of Neurological Disorders and Stroke. Symptoms of Parkinson's disease result from the destruction of neurons in the areas of the brain called the substantia nigra which produce the neurotransmitter dopamine. Without these neurons, the amount of dopamine in the brain decreases, affecting neural communication between the substantia nigra and the corpus striatum, resulting in impaired movement.

Parkinson's disease has four major symptoms: postural instability, rigidity, bradykinesia and tremor. With postural instability, patients fall easily and may also have a stooped posture. The National Institute of Neurological Disorders and Stroke noted that most Parkinson's disease patients have rigidity, in which the muscles are contracted and tense. Movement of a patient's arm results in short and jerky motions. Bradykinesia is the slowing or loss of patients' automatic and spontaneous movements, which affects how quickly they can do daily activities, such as dressing themselves. With the tremors, they have a rhythmic motion at 4 to 6 beats per second, according to the National Institute of Neurological Disorders and Stroke. They can start in the hand, jaw or foot, and are noticeable when the affected area is resting or if a patient is stressed.

Helping patients manage these symptoms is a goal of Parkinson's disease treatment. New studies suggested that low-intensity exercise and a drug called safinamide may help Parkinson's disease patients with movement difficulties. The exercise study was conducted by the University of Maryland and included 67 Parkinson's disease patients who were divided into three groups: high-intensity treadmill, low-intensity treadmill, and stretching and resistance training. The high-intensity group exercised at a greater speed and shorter duration and the low-intensity group exercised at a lower speed and longer duration. Maureen Salamon of HealthDay News reported that on distance and speed tests, the Parkinson's disease patients who did the low-intensity exercise performed better and also have improvements in their mobility and gait.

The other study looked at combining the drug safinamide with levodopa, a medication commonly used to treat Parkinson's disease that converts to dopamine. Safinamide inhibits the enzyme monoamine oxidase B (MAO-B), an enzyme that breaks down dopamine. The Parkinson's disease patients in the safinamide-levodopa study had mid- to late-stage Parkinson's. The 669 patients were already on levodopa and were given either a placebo, 50 mg of safinamide or 100 mg of safinamide, which was taken daily. Salamon reported that the study did not find significant improvements overall in involuntary movements in patients who took safinamide; but in severe dyskinesia Parkinson's disease patients who took 100 mg of safinamide, they had a 24 percent reduction on average in their movement difficulties. Currently, the U.S. Food and Drug Administration has not approved safinamide. The results from both studies are also preliminary as they have not been published yet in a peer-reviewed journal.

References

National Institute of Neurological Disorders and Stroke. Parkinson's Disease: Hope Through Research. National Institutes of Health, 2011. Web. 30 May 2011
http://www.ninds.nih.gov/disorders/parkinsons_disease/detail_parkinsons_disease.htm

A.D.A.M. Parkinson's Disease. MedlinePlus, 2010. Web. 30 May 2011
http://www.nlm.nih.gov/medlineplus/ency/article/000755.htm

Salamon, Maureen. Low-Intensity Exercise, Drug Combo Can Help Parkinson's Patients, Studies Show. HealthDay, 12 April 2011. Web. 30 May 2011
http://consumer.healthday.com/Article.asp?AID=651723

ClinicalTrials.gov. Open-Label Trial to Determine the Long-Term Safety of Safinamide in Parkinson's Disease Patients. National Institutes of Health, 2010. Web. 30 May 2011
http://www.clinicaltrials.gov/ct2/show/NCT00865579

Reviewed May 30, 2011
Edited by Alison Stanton