“Knowing more about PD is helpful. It’s understanding PD that makes for a better life.”
—WARREN E., PWP
Some people have an atypical parkinsonian disorder but are misdiagnosed as having Parkinson’s disease instead because their symptoms can resemble those of PD in the first few years of the disorder. These disorders have also been called Parkinson’s plus because they have Parkinson’s symptoms plus other symptoms and can mimic idiopathic PD.
Below are the major ways in which atypical parkinsonian/Parkinson’s plus disorders differ from idiopathic Parkinson’s.
• Carbidopa-levodopa and dopamine agonists provide only mild to modest benefit, which is lost as the disease progresses.
• Atypical parkinsonian disorders show additional symptoms that people with PD do not have. For example, in corticobasal degeneration there is the alien limb syndrome (not feeling in control of the activities of an arm or leg) and significant apraxia (not being able to perform simple motor actions), and in progressive supranuclear palsy (PSP) eye movements that are typically fast become very slow, especially in the vertical direction.
• Resting tremor is uncommon in atypical parkinsonian disorders, but people often experience walking difficulty and falls much earlier in these disorders.
People with DLB have problems with tremor, stiffness, and slowness, just like people with Parkinson’s, but in addition to these movement problems they have significant thinking and memory problems as well. These all tend to show up at the same time, or within a year of one another. This differs from Parkinson’s disease dementia (PDD), in which the memory problems develop later on in the disease. You can read more about PDD in chapter 56.
Other symptoms of DLB include depression and anxiety, delusions, visual hallucinations, sleep problems (e.g., acting out dreams), aggression, loss of motivation, and confusion and alertness that vary significantly from day to day. You can read more about DLB in chapters 56 and 57.
This common PD look-alike disorder comes in three forms: MSA-A (multiple system atrophy-autonomic or primary autonomic failure), MSA-C (multiple system atrophy-cerebellar, formerly known as Shy-Drager syndrome), and MSA-P (multiple system atrophy-Parkinson, formerly known as striatonigral degeneration [SND]). All three types of MSA are characterized by disabling blood pressure fluctuations causing lightheadedness or fainting, as well as urinary frequency, urgency, or incontinence much earlier than in PD.
MSA-A—This condition causes significant blood pressure fluctuations and bladder problems for years before parkinsonism is noted.
MSA-C—People with this condition will notice problems with balance early on and will experience incoordination, clumsiness, and falls. Also, their voice may be hard to understand. An MRI might show that their cerebellum has shrunk.
MSA-P—People with this condition may notice a flexed neck early on. They then become stiff and slow and develop difficulties with balance and walking. Usually there is no tremor. MSA-P and PD resemble each other in the early stages, but MSA-P symptoms do not respond as well to levodopa as PD symptoms do.
People with this uncommon disorder have difficulties shifting their gaze vertically (upward or downward). They also develop early balance problems and difficulties with speaking and swallowing. There are several varieties of this disorder that overlap with PD, which makes distinguishing between the two disorders challenging.
People with PSP do not respond well to levodopa, and though there is no specific treatment for this disorder, a neurologist can offer suggestions on ways to ease symptoms.
CBD is the least common of the atypical parkinsonian disorders. If you have CBD, you will typically notice that movement symptoms start and remain predominantly on one side of your body. You may have trouble controlling one of your arms, or it may even do something you don’t want it to—a condition called alien limb syndrome.
Other symptoms you may experience with CBD include gait and balance problems, memory and thinking problems, stiffness, slowness, and language problems. CBD progresses more slowly than other PD look-alikes and may look like progressive supranuclear palsy at first. Like PSP, there isn’t a specific drug for CBD, but levodopa and rehabilitation should be considered since they may improve motor symptoms even if only to a modest degree.
PD–ALS occurs among certain populations on the island of Guam and may be accompanied by a disease resembling amyotrophic lateral sclerosis (ALS, Lou Gehrig’s disease). The progression of this disease is fast, with people usually dying within 10 years of being diagnosed. To date, researchers have investigated environmental toxins, infectious agents, mineral deficiencies, and genetics as possible causes of this disease.20
Some researchers wonder if the use of flour from the highly toxic seed of the cycad plant could be a culprit.21 This has been found to be unlikely, however, as a person would need to ingest about 70 kg of flour to receive a toxic dose of the plant.22 More research needs to be done to determine definitive causes of this disorder.
A note about MSA: The current survival rate is about 7 to 10 years after the first symptoms appear. That said, this number varies greatly, and sometimes people can live 15 years or longer.