Parkinson-plus syndromes are a group of neurological conditions that are similar to Parkinson's disease but have unique characteristics. These syndromes can be difficult to diagnose because the symptoms mimic other conditions. Following are the four most common types of Parkinson-plus syndromes.
Progressive supranuclear palsy (PSP)
PSP is a rare disorder that, like Parkinson's disease, causes problems with balance and stability when a person is walking or standing. Rigid and stiff muscles, especially those of the neck and spine, make body movement difficult. The symptom that most distinguishes PSP from Parkinson's disease and other neurologic conditions is difficulty with eye movement that occurs in addition to the body movement problems.
Difficulty with speech and swallowing are more common and become worse in PSP than they do in Parkinson's disease. Depression and emotional difficulties are also more prominent. Unlike Parkinson's disease, PSP rarely causes tremors. PSP progresses more quickly than Parkinson's and often leads to disability within 5 to 10 years.
While there is currently no cure for PSP, some symptoms may be controlled with medications. Symptoms of depression that are related to PSP may improve with antidepressant medications, and some movement problems may respond to antiparkinson medications such as levodopa.
Multiple system atrophy (MSA)
MSA is a series of three related disorders that slowly but progressively affect the nervous system. One disorder (called olivopontocerebellar atrophy, or OPCA) causes problems with balance, coordination, and speech. A second disorder (called striatonigral degeneration) causes slow body movement and stiff muscles similar to Parkinson's disease. The third disorder (called Shy-Drager disease) interferes with automatic body functions that are controlled by the autonomic nervous system, such as breathing, heart rate, digestion, and blood pressure.
Parkinson-like symptoms of MSA include stiff and rigid muscles and limbs, loss of balance and coordination when walking, difficulty swallowing and speaking, blurred vision, constipation and urination problems, and erectile dysfunction. Both MSA and Parkinson's disease can cause dizziness when standing up (orthostatic hypotension) due to a drop in blood pressure, which, in MSA, may be severe enough to cause brief blackouts. There is no effective way to stop the nerve degeneration that occurs with MSA, but medications can help relieve symptoms.
Cortical-basal ganglionic degeneration (CBGD)
CBGD is a rare neurological disorder that, over time, causes many areas of the brain to shrink. Initial symptoms may appear on only one side of the body but eventually affect both sides as the disease progresses. Some symptoms of CBGD are similar to Parkinson's disease, such as stiff, rigid movements, tremor, problems with balance and coordination, difficulty speaking and concentrating, and progressive problems with moving, thinking, and remembering.
Gradually, problems with understanding spoken or written language may develop. A phenomenon called "alien limb" can occur in which the person has difficulty controlling the movement of a limb.
Although there is no cure for CBGD, medications are available to treat its symptoms. Treatment can improve a person's daily functioning and quality of life.
Dementia with Lewy bodies (DLB)
DLB is a brain disease that causes progressive changes with movement or thinking. In DLB, abnormal structures called Lewy bodies form in certain areas of the brain. Sometimes the symptoms of DLB resemble those of Parkinson’s disease—such as a shuffling gait, tremor, and difficulty with movement. In other cases, symptoms of DLB (such as confusion and memory loss) may mimic the symptoms of Alzheimer’s disease. Often a combination of both Parkinson’s and Alzheimer’s symptoms appear together. These symptoms may occur in DLB because the structures in the brain affected by DLB are similar to those affected by Parkinson’s disease or Alzheimer’s disease. Some experts think that DLB may be a form of Parkinson’s disease or Alzheimer’s disease.
The progression of DLB is slow. Although there is no cure for DLB, treatment is available to reduce symptoms of the disease.