Department: Ask the Experts
Janis Miyasaki, M.D., is associate clinical director of the Toronto Western Hospital Movement Disorders Centre at the University of Toronto. She co-authored the American Academy of Neurology's new guidelines for treating Parkinson's disease.
Q My mother was recently diagnosed with Parkinson's and is becoming more and more forgetful. Is this a symptom of the disease?
A As many as 70 percent of Parkinson's patients will ultimately end up developing dementia–usually in the later stages of the disease.
Figure. DR. JANIS MI...Image Tools
Even in the early stages of the disease, tests show some patients starting to have subtle changes in thinking. These patients may not be able to access information as efficiently as they once did. They can have trouble doing two things at once.
One problem is that the medications we give Parkinson's patients to help with motor problems can lead to worsening memory, confusion, hallucinations and delusions.
The good news is that the drugs used to treat Alzheimer's seem to be more effective in patients with Parkinson's dementia. But these medications also can worsen a patient's motor symptoms. Some notice they are slower and stiffer when taking these drugs. Some have increased tremor.
So, there's a trade-off. If a patient is reporting problems with memory and thinking and is having some hallucinations, I will try reducing the dosage of some of the less effective Parkinson's drugs. And I will try them on the lowest doses of an Alzheimer's medication.
However, I might just leave everything alone, if the cognitive problems are minor. Nothing needs to be done so long as their mental deficits aren't having a major impact on safety and quality of life: if they can still manage their money, pay their bills and they remember to turn off the stove, for example.
The memory problems you mention are a sign that you'll need to become more involved in your mother's care and life. And you probably should be attending her doctor's visits.
You are wise to observe these changes and you need to bring them up with her physician. Looking after the physical symptoms of Parkinson's can be so challenging that sometimes the physician may miss cognitive and behavioral problems.