Re: World PD prevalence estimates

[robert l dolezal <bobbylu@xxxxxxxxxxxxx>]

I like Phil's methodology.

I sent an e-mail to the Journal, questioning the data, and I sent a cc to
the Listserv.  Perhaps it did not get through, so I'll try to attach it
here.  Anyhow, I received a short "thank you" for the Journal, indicating
that they would be responding "soon."   We'll see.


                                                               October 15, 1998

To the editor:

I am writing to request clarification of statistical data presented in The
New England Journal of Medicine 1998;339:1105-1111, an article entitled
"Brain Surgery Helps Severe Parkinson's."

The reason this is an important issue to those of us with Parkinson's is
that data like these, promulgated by such a respected journal, has a way of
becoming accepted by those dealing with it.  In our case it can be used to
sway political decisions regarding government research funding.

The article states:  "About 7 million people around the world have
Parkinson's disease, which usually strikes after age 60, causing
progressive tremor, muscle rigidity and other movement problems."

First, what is the source for a PD population of 7 million "around the world?"

If, as is frequently stated, up to 1.5 million have PD in this country,
with a population of only 290 million people, how can there be only 7
million with the disease in a world of about 6 billion people?  About 4.5%
of the world's poulation has 21.4% of the world's Parkinson's population?

Second, what is the source for the conclusion that Parkinson's  "...usually
strikes after age 60."

All these years, based primarily on personal observation, I had thought
that the oft-repeated average of 57 AT DIAGNOSIS was far too old.  Now we
are told that the disease STRIKES "after age 60."  Clearly, I and most
everyone I know with the disease must have been preemies.  I was diagnosed
at 57, but I now know that the disease had "struck" - atrophy of right
bicep, cold hand, stiff and sore fingers - at least seven years previous.

We look forward to receiving your reply.

                                Sincerely,

                                Bob Dolezal
                                Parkinson's Advocate

At 9:42 AM 10/16/98, Phil Tompkins wrote:
>robert l dolezal, who has sharp eyes, wrote:
>
>> ... but where did these guys come up with a PD population of 7
>> million "around the world?" .... for starters, if up to 1.5 million
>> of us have it in the U. S. of A., with a mere 290 million people,
>> how can there be only 7 million with the disease in a world of
>> about 6 billion people?
>
>Well, it's an improvement over the World Health Organization's
>3.6-3.7 million total, based on a world prevalence percent of .07
>that they came up with!  - see
>
>www.who.int/msa/mnh/ems/rates/parkinso.htm
>
>This got me going, so I looked up some of the many population
>numbers that the US Census Bureau provides on-line, and found this:
>
>The US has 4.6 percent of the world's population (265 million out
>of a world estimate of 5.77 billion in 1996).  But in the prime
>PD age bracket of 45 years old & up the US has 6.6 percent (83
>million out of an esimated world total of 1263 million), and 7.8
>percent of people 65 and up.
>
>Using the 45 and up age bracket and assuming (and I have no right to
>such an assumption) a uniform world prevalence rate and 1 million
>PWPs in the US, that would give about 15 million PWPs worldwide
>(plus or minus some big error amount) as a very rough ballpark
>figure, which should perhaps be reduced a bit owing to a somewhat
>shorter life expectancy in the non-industrialized world.
>
>Phil Tompkins
>Hoboken NJ
>age 60/dx 1990