PD and Sunlight Data - Part 1
 

This is something that I had been meaning to do for some time. The information linking sunlight and MS made me get off my butt and do it. I am posting this as two separate "sorts". This one lists the states by the PD rate as a percentage of the population as determined by the NPF analysis of drug company data of Sinemet sales. In the world of PD research, that is probably the best data ever gathered on this demographic. See Lieberman's "Shaking Up Parkinson's Disease". The second sort is arranged by latitude and follows this post as Part 2. Finally, the fun begins with Part 3 - Analysis.


State by State Comparison of
PD Rates and Latitude

Sorted by PD Rates (Column 2)
Column 3 is distance above
equator in degrees (Latitude)

State PWP (%) Lat (GeoCntr)

HI 0.18 21.1
DE 0.19 39.3
MD 0.21 39.1
WY 0.21 42.7
CA 0.22 36.2
VA 0.22 37.8
NM 0.24 34.8
NV 0.25 38.4
DC 0.25 38.9
MA 0.25 42.2
NH 0.25 43.4
SC 0.27 33.8
CO 0.27 39.1
TX 0.28 31.1
NC 0.29 35.6
AK 0.29 61.4
GA 0.3 33
NJ 0.3 40.3
WA 0.3 47.4
LA 0.31 31.2
MS 0.32 32.8
IL 0.32 40.3
OH 0.32 40.4
CT 0.32 41.6
NY 0.32 42.1
RI 0.34 41.7
IN 0.35 39.9
PA 0.35 40.6
MI 0.35 43.4
ME 0.37 44.6
MT 0.37 46.9
KY 0.38 37.7
MO 0.4 38.4
UT 0.4 40.1
VT 0.41 44.3
AL 0.41 32.8
AZ 0.41 33.8
FL 0.42 27.8
WI 0.42 44.3
OR 0.42 44.6
OK 0.43 35.5
KS 0.45 38.5
ID 0.45 44.2
TN 0.47 35.7
AR 0.55 34.9
WV 0.55 38.5
MN 0.63 45.7
NE 0.68 41.1
IA 0.68 42
SD 0.73 44.3
ND 0.9 47.5

PD and Sunlight - Part 2 (by Latitude)
 

State by State Comparison
of PD Rates and Latitude

Sorted by Latitude (Column 3)
Column 2 is PD Rate


State PWP (%) Lat (GeoCntr)


HI 0.18 21.1
FL 0.42 27.8
TX 0.28 31.1
LA 0.31 31.2
AL 0.41 32.8
MS 0.32 32.8
GA 0.3 33
AZ 0.41 33.8
SC 0.27 33.8
NM 0.24 34.8
AR 0.55 34.9
OK 0.43 35.5
NC 0.29 35.6
TN 0.47 35.7
CA 0.22 36.2
KY 0.38 37.7
VA 0.22 37.8
MO 0.4 38.4
NV 0.25 38.4
KS 0.45 38.5
WV 0.55 38.5
DC 0.25 38.9
CO 0.27 39.1
MD 0.21 39.1
DE 0.19 39.3
IN 0.35 39.9
UT 0.4 40.1
IL 0.32 40.3
NJ 0.3 40.3
OH 0.32 40.4
PA 0.35 40.6
NE 0.68 41.1
CT 0.32 41.6
RI 0.34 41.7
IA 0.68 42
NY 0.32 42.1
MA 0.25 42.2
WY 0.21 42.7
MI 0.35 43.4
NH 0.25 43.4
ID 0.45 44.2
SD 0.73 44.3
VT 0.41 44.3
WI 0.42 44.3
ME 0.37 44.6
OR 0.42 44.6
MN 0.63 45.7
MT 0.37 46.9
WA 0.3 47.4
ND 0.9 47.5
AK 0.29 61.4

PD and Sunlight - Part 3 Discussion
 

I will try to put this in the form of a map later, but it is already clear that a definite pattern exists. The farther from the equator, the higher the PD rate. If you go through and edit out things like Florida and Alaska (high immigrant populations) or the extremes of the data set, the pattern gets even more defined. Some of you with a decent statistics background should work this over a little.

The temptation to yell "Vitamin D" is very strong here, but there is at least one other possibility to consider - circadian rhythms. I lived a short while in Alaska and the short days of winter were a real bummer. We all know of SAD and keep in mind what a problem depression is for some of us too. Insomnia can be another manifestation of circadian rhythm, as well. Don't underestimate its power as extreme disruption can kill you once it has driven you mad.

It is almost certain to be the combination of the two.

Just for fun let's look at the 20 southernmost states and compare with the 20 most northern.

Southernmost
HI 0.18 21.1
FL 0.42 27.8
TX 0.28 31.1
LA 0.31 31.2
AL 0.41 32.8
MS 0.32 32.8
GA 0.3 33
AZ 0.41 33.8
SC 0.27 33.8
NM 0.24 34.8
AR 0.55 34.9
OK 0.43 35.5
NC 0.29 35.6
TN 0.47 35.7
CA 0.22 36.2
KY 0.38 37.7
VA 0.22 37.8
MO 0.4 38.4
NV 0.25 38.4
KS 0.45 38.5

Avg = 0.34

Northernmost
NE 0.68 41.1
CT 0.32 41.6
RI 0.34 41.7
IA 0.68 42
NY 0.32 42.1
MA 0.25 42.2
WY 0.21 42.7
MI 0.35 43.4
NH 0.25 43.4
ID 0.45 44.2
SD 0.73 44.3
VT 0.41 44.3
WI 0.42 44.3
ME 0.37 44.6
OR 0.42 44.6
MN 0.63 45.7
MT 0.37 46.9
WA 0.3 47.4
ND 0.9 47.5
AK 0.29 61.4

Avg = 0.43

Thankyou for your most interesting posts.You are indeed a goldmine of information.... Thankyou too for the help you gave me with advice on the supplements it would be helpful for me to take.
I live in Scotland, a very northerly climate, and one that sees some of the highest numbers of MS patients in the world. Do you know what the PD statistics are for Scotland? Also, may I ask what your profession is? Do you have a scientific background? Hope that doesn't sound prying!
Kind regards, Ladybird.

Ladybird-
I'm sorry but I don't have any reliable figures. That is one reason the US data is so pleasing. Good numbers are hard to come by.

My profession was a professional land surveyor (US definition) followed by a developer of residential property. I've always had a scientific bent and had two years at university studying whatever caught my fancy knowing that the money was going to run out. That freed me from a lot of BS. When I was diagnosed in 2000 my first reaction was to hit the books and I never stopped. One thing particularly unique about my background is that the Net made it possible to for me to "apprentice" with a French surgeon, Anne Frobert, who was battling PD herself. It is part dedication and a good part of harnassed OCD, but it works for me.


I live in Scotland, a very northerly climate, and one that sees some of the highest numbers of MS patients in the world. Do you know what the PD statistics are for Scotland? Also, may I ask what your profession is? Do you have a scientific background? Hope that doesn't sound prying!
Kind regards, Ladybird.[/QUOTE]

Here is a map
 

The attached file is a US map with each state color coded for how common PD is. The color bar at he left side represents PD with most severe at the top. I tried to use dark, heavy color for the hardest hit areas and gradually faded to light pastels in lighter hit areas. As expected, the upper Midwest stands out. Also, I sketched out the major watersheds with the heavy red lines.

It is odd that the watershed boundaries would matter, but they do a pretty good job of blocking out the major disease areas. I don't think that it could be solely pollution in the water since New Orleans doesn't show it. What about air pollution?

I no longer am so sure about Vitamin D alone, but a deeper analysis might still turn it up. Cheers.

Sunshine and excercize help ALOT. Sometimes I can go easily without a dose when out working in my sunny garden. Days it rains or I am at work and indoors m,ost of the day, I don't feel as well and need more tiincture .

Thanks for the data Rick.

Using this data directly gives a correlation of almost 0.25, from which (taking the square) it's reasonable to estimate 6% of the variance in PD rates is due to factors linked with latitude. Even then we are not talking causality.

The analysis would be improved if:
- we weighted the data by population;
- used the population centre of gravity for each state;
- used UV data.

John

I confess to skipping statistics
 

Calculus was bad enough. :) If you can find anything of use in the data, feel free to run with it and report back. I wonder if there is any decent state by state data for SAD? That might be interesting.....