The progression of Parkinson's disease symptoms can take 20 years or even longer. But the rate of progression varies from person to person.
To give patients an idea about how far their disease has progressed, many doctors use the Hoehn and Yahr scale for the staging of Parkinson's disease, which is broken down into the following stages:
• Stage one: Parkinson's disease symptoms affect only one side of the body.
• Stage two: Symptoms begin affecting both sides of the body, but balance is still intact.
• Stage three: Parkinson's disease symptoms are mild to moderate and balance is impaired, but the person can still function independently.
• Stage four: People with stage four Parkinson's disease are severely disabled, but they can still walk or stand without assistance.
• Stage five: The patient becomes wheelchair-bound or bedridden, unless someone is helping him.
While your doctor may be able to tell you how far along you are on this scale, there is no accurate way of predicting how soon you will get to the next stage. However, you can expect that as you notice your symptoms worsening, your physical functioning will also start to decline.
Parkinson’s Disease Symptoms: Dementia
Some Parkinson's disease patients experience dementia, or impairment of mental functioning. About 0.2 percent to 0.5 percent of those with Parkinson’s over age 65 will have problems with dementia, including trouble with their memory, attention spans, and what is called executive function — the process of making decisions, organizing, managing time, and setting priorities.
How Parkinson’s Disease Symptoms Respond to Treatment
There is no cure for Parkinson's disease, but treatments can help ease your symptoms.
Tracking your response to treatment is another way doctors can determine how advanced your condition is. The stages of Parkinson's treatment generally progress in the following order:
1. No medication needed. In its early stages, Parkinson's disease symptoms may be very mild and may not need to be treated.
2. Good response to medication. As your symptoms begin affecting your functioning, the Parkinson's medication Sinemet or Parcopa [carbidopa and levodopa]) is usually able to significantly and effectively reduce symptoms for one to five years — longer in about 25 percent of patients.
3. Waning medication response. When the effectiveness of Sinemet or Parcopa begins to wear off (its effects will last for increasingly shorter periods of time as the disease progresses), you will need to increase the amount of medication, or add another medication called a COMT inhibitor [Comtan (entacapone); Tasmar (tolcapone)] that essentially boosts the efficacy of the carbidopa/levodopa combo.
4. Unpredictable medication response. Instead of occurring at predictable intervals, breakthrough symptoms begin occurring at random, and may be triggered by stress and anxiety. At this point, medications will need to be continuously monitored, and Parkinson's surgery may become a treatment option.
5. Dyskinesias. Dyskinesias are involuntary movements that tend to occur when your medication dose has reached its peak performance. When this happens, adjusting your medication dosing, taking a medication called Symmetrel (amantadine), and perhaps surgery may also help.
6. Severely unpredictable symptoms. In the most advanced stages of Parkinson's disease's, severe symptom flare-ups alternating with severe dyskinesias will occur, despite medication adjustments. At this point, surgery is often the best treatment option. Called deep brain stimulation, this surgery involves implanting electrodes in the brain that are connected to an external device somewhat like a heart pacemaker that helps control electrical impulses affecting movement and flexibility.
Parkinson's Disease Symptoms: Life Expectancy
Even though Parkinson's disease is a serious, progressive condition, it is not considered a fatal illness. People who have Parkinson's disease usually have the same average life expectancy as people without the disease. However, when the disease is in its advanced stages, Parkinson's disease symptoms can lead to life-threatening complications, including:
•Falls that lead to fractured bones
Thinking about the progression of Parkinson's disease can be frightening. But proper treatments can help you live a full, productive life for years to come. And good news may be on the horizon. Researchers believe that they will one day find ways to halt the progression of Parkinson's disease and even restore lost functioning.