The Parkinson’s Disease Foundation points out that about one million people in the United States have Parkinson’s disease, with about 60,000 people diagnosed with the disorder each year. A neurological condition, Parkinson’s disease occurs when dopamine-producing brain cells become destroyed. Dopamine is a neurotransmitter, and as MedlinePlus notes, is involved in muscle control. When Parkinson’s disease patients have that decrease in dopamine, they experience problems with movement.
Symptoms of Parkinson’s Disease
MedlinePlus explains that at first, the symptoms of Parkinson’s disease are mild, though they become worse as the disease progresses. With the motor symptoms of Parkinson’s disease, patients can have problems walking. For example, they may have difficulty starting movement or slowed movement. When walking, they have a shuffling gait. Balance is also impaired, and patients may have a stooped position. Parkinson’s disease patients may have stiff muscles in their legs. Some patients may have muscle pain.
Parkinson’s disease can also cause a loss of fine hand movements, which can make it difficult to carry out tasks that involve holding an object. Many Parkinson’s disease patients experience tremors, which start when the patients’ limbs are at rest. Once patients start using the affected limbs, the tremors go away. The tremors can become worse when patients are tired, stressed or excited. As the disease progresses, patients can have tremors in their feet, head, lips and tongue.
Parkinson’s disease can cause other symptoms. For example, patients can have cognitive problems, such as memory loss, confusion and dementia. Some patients may have hallucinations, in which they perceive something that is not there. Parkinson’s disease patients may have anxiety or depression. The disease can cause a mask-like appearance in which patients do not display emotions on their face. Other symptoms of Parkinson’s disease include constipation, oily skin, fainting, difficulty swallowing, drooling, slowed speech and a monotone voice.
Deep Brain Stimulation for Parkinson’s Disease
One option for treating Parkinson’s disease is deep brain stimulation (DBS) by using so called brain pills. This treatment helps particularly with the walking problems, tremors, slowed movements, rigidity and stiffness. DBS is a surgical procedure in which the surgeon implants an electrode, or lead, into the patient’s brain at specific motor locations. The lead connects to an extension wire, which attaches to the neurostimulator. The National Institute of Neurological Disorders and Stroke (NINDS) explains that the neurostimulator sends the electrical impulses through the extension to the lead, where the electrical impulses block “the abnormal nerve signals that cause tremor and [Parkinson’s disease] symptoms.”
A study published in the New England Journal of Medicine with funding from the Department of Veterans Affairs (VA) and the NINDS investigated the use of DBS for Parkinson’s disease at two different sites in the brain. The two sites that surgeons implanted the electrode in were the subthalamic nucleus and the globus pallidus interna, which are both part of the basal ganglia system.
The study included 300 Parkinson’s disease patients who were followed for two years. Stimulation to both the subthalamic nucleus and globus pallidus interna provided benefits for patients, as both brain regions are linked to motor control pathways. The researchers found that the most effective method was bilateral stimulation, meaning both sites received electrical stimulation from the neurostimulator.
DBS can help greatly with Parkinson’s disease. While medications like L-dopa can improve motor symptoms, they become less effective as the disease progresses. But as the researchers of the DBS study note, DBS does not treat the non-motor symptoms of Parkinson’s disease and may worsen them in some patients. As a result, Parkinson’s disease patients undergoing DBS still need to take medications for the other symptoms of the disease.