Op-Ed: Recent PD/dementia research proves more research is needed

Posted Jan 24, 2012 by Bill Schmalfeldt
What are we as patients to conclude from Parkinson's disease research that comes to the conclusion that "more research is needed"?
It is  indeed  a cruel master. But more research is needed.
It is, indeed, a cruel master. But more research is needed.
Much of the talk in the Parkinson's disease research community of late has been about a study showing that the onset of dementia is a predictor of mortality in folks diagnosed with PD at age 65 or older.
The study, published in the Jan. 2 edition of the Archives of Neurology showed something that I always believed common sense already dictated. "Demographic and clinical factors impact PD survival."
Well, duh!
Demographic factors such as age of onset of any disease and clinical factors such as what else you're suffering from along with the disease being studied will almost always impact how long you survive. I'm sure this is true with everything from colon cancer to cardiovascular disease.
The study further concludes, "Dementia is highly prevalent in patients with PD and is associated with a significant increase in mortality. More research is needed to understand whether environmental exposures influence PD course or survival."
Again, a well-considered "duh" seems to be appropriate.
If you live long enough with Parkinson's disease, your chances of developing Parkinson's disease dementia (PDD) rise with each year since your diagnosis. A website that summarizes medical research on specific topics indicates that if a person lives until 90 years of age, no matter when they were diagnosed with Parkinson's disease, he or she has a 80 to 90 percent chance of developing dementia. Put simply, if you live a good long time and have Parkinson's for a good, long time, you will almost certainly develop dementia. And everybody dies.
No exceptions.
Not to say there weren't some interesting tidbits for the layperson in this study. For instance, the six-year study of 138,728 Medicare patients showed that 64 percent of these folks who were diagnosed at age 65 or older were dead by the end of the study. Dementia was diagnosed in 69.6 percent of these folks. African Americans and women were the most likely to die after developing PDD, not from Parkinson's disease, but from a myriad of other causes such as cardiovascular disease and infections like pneumonia. Yet women, Hispanics and Asians were less likely to develop dementia during the course of the study.
OK, that's enough to digest for the moment. But of what import is this study to those of us who were not diagnosed before the age of 40 -- the so-called Young Onset Parkinson's Disease (YOPD) cohort and this group who had incident PD at the age of 65 or older?
The answer?
"More research is needed."
To be fair, the definition of YOPD depends on which doctor you're talking to or which web site you're looking at. The American Parkinson's Disease Association defines YOPD as being diagnosed between the ages of 21-40. The National Parkinson Foundation says anyone 50 or younger who gets the diagnosis qualifies as YOPD. WebMD is less specific, saying that 10-20 percent of PD cases are diagnosed under the age of 50. Even that number varies. The National Institute of Neurological Disorders and Stroke at the National Institutes of Health says YOPD means 50 or younger at diagnosis, but that only 5-10 percent of all cases fit that description.
Hence the confusion.
One can find research about longevity for YOPD patients. As you've seen, there's much research on folks who get diagnosed at age 65 or older.
Occasionally, one finds a study published that shows life expectancy figures for all the various PD groups, like in the one published in 2007 in the Journal of Neurology, Neurosurgery and Psychiatry that indicates folks diagnosed before the age of 39 will live an average of 38 years with Parkinson's. Those of us diagnosed between the ages of 40 and 64 have an average of 21 years to look forward to. Those who get the word at age 65 or older had best get their affairs in order in an average of 5 years... which isn't all that different from the average longevity of the 65 year old diagnosed with Parkinson's in the aforementioned study that is the subject of this story.
When you put all these numbers together and consider them very carefully, there is only one conclusion one can come away with.
More research is needed. Duh.
(The attached video displays your humble writer displaying his latest problem with this exquisite little inconvenience known as Parkinson's disease -- and why he can't go outside unless his wife says so.)