Meteorological epidemiology of Parkinson's Disease

Papers such as that by Willis et al. [1] show that there are geographical differences in the prevalence of Parkinson's disease. In their analysis of US data, they show that there is a zone of low prevalence in the Rocky mountains and a zone of higher prevalence to the east of a line drawn between Texas and the Great Lakes.

Other work, see for instance the thread "Temporal Epidemiology" [2] shows an annual cycle in the number of deaths in the US where PD is a factor, with high numbers dying in the winter and lower numbers dying in the summer. Typically people die with PD rather than from PD, and even then after a long period of chronic illness. So it does not necessarily mean that the etiology of PD involves the same periodicity. Nevertheless, one can speculate that the recurrence of the conditions that set in motion the process that led to PD in the first place also hasten its increasing severity.

The obvious common denominator between spatial changes and annual changes is the weather.

There appears to be little work published in analysing the prevalence of Parkinson's either in terms of short term meteorological effects or longer term climatic effects. There is no suggestion that weather per se causes PD but, rather, that meterological conditions can modulate possible disease vectors.

Rick, to whom my thanks, started a thread [3] that asked whether temperature was a factor in PD.

There appears to be an association between the prevalence of PD in the US and the annual mean rainfall [4], with areas of higher rainfall having on average higher levels of PD.

Also, there is a striking association between the partition of the US into west (lower PD) and east (higher PD) parts and the position of a zone of mean surface level winds which are for much of the year southerly (that is, from the south to the north) [5] that starts in Texas and continues north towards the Canadian border.

There are many ways in which meteorology could play a role in the etiology of Parkinson's. These include:
- create the conditions for pathogens to thrive or to die. For instance, Science Daily reports [6] that "Two types of environmental conditions -- cold-dry and humid-rainy -- are associated with seasonal influenza epidemics".
- distribute toxins;
- wash-out toxins and pathogens suspended in the atmosphere.

If these areas were proven to be material in the etiology of Parkinson's, it would take us a step closer to being able to control the disease.

References

[1] "Geographic and Ethnic Variation in Parkinson Disease: A Population-Based Study of US Medicare Beneficiaries"
Allison Wright Willis, Bradley A. Evanoff, Min Lian, Susan R. Criswell, and Brad A. Racette
Neuroepidemiology. 2010 April; 34(3): 143–151
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2865395/

[2] http://neurotalk.psychcentral.com/sh...light=temporal

[3] http://neurotalk.psychcentral.com/sh...hlight=climate

[4] "Precipitation: Annual Climatology (1981-2010)"
Natural Resources Conservation Service
http://www.wcc.nrcs.usda.gov/climate/prism.html

[5] "CLIMATOLOGICAL MEAN AND INTERANNUAL VARIANCE OF UNITED STATES SURFACE WIND SPEED, DIRECTION AND VELOCITY"
KATHERINE KLINK
Int. J. Climatol. 19: 471–488 (1999)
http://www.researchgate.net/...mean...._IJOC_1999.pdf

[6] "New Light Shed On Role of Climate in Influenza Transmission"
Science Daily, Mar. 7, 2013
http://www.sciencedaily.com/releases...0307190635.htm

John

As pointed out above, any hypothesized etiology of Parkinson's must be consistent with the Willis [1] paper's message. Here we note that this must be true both in general terms and in local terms. It is perhaps too easy to put local variations down to "noise".

Winds, both at surface and higher levels, can spread material through the atmosphere. Ultimately, this paints the general picture. But it takes meteorological deposition, the process whereby particles (dust, metals, spores, viruses etc.) fall from the atmosphere when there is insufficient updraught to support their weight or when gases are washed out of the atmosphere by precipitation, to paint in the fine detail.

I've not been able to find any material of this type for Parkinson's. However, Firestone et al. [2] do a meteorological analysis of the spread of equine flu. They take into account factors such as wind velocity, humidity, precipitation and temperature. Additional factors, such as temperature inversions, could also be considered.

Finally, let's address how we might narrow down the number of possible causes of PD. We could run the model in reverse, taking backward trajectories, leading from the destination to the source. The problem is that we don't know the size of particle we are dealing with. But we might be able to argue that the lumpiness of the prevalence distribution precludes certain particle sizes.

References

[1] "Geographic and Ethnic Variation in Parkinson Disease: A Population-Based Study of US Medicare Beneficiaries"
Allison Wright Willis,a,* Bradley A. Evanoff,b Min Lian,b Susan R. Criswell,a and Brad A. Racettea
Neuroepidemiology. 2010 April; 34(3): 143–151.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2865395/

[2] "The Influence of Meteorology on the Spread of Influenza: Survival Analysis of an Equine Influenza (A/H3N8) Outbreak"
Simon M. Firestone, Naomi Cogger, Michael P. Ward, Jenny-Ann L. M. L. Toribio, Barbara J. Moloney, Navneet K. Dhand
PLoS ONE 7(4): e35284. doi:10.1371/journal.pone.0035284, 2012
http://www.plosone.org/article/info%...l.pone.0035284

John

"The causal agent of the disease remains unknown after more than 40 years of intensive research. The number of cases continues to rise in many parts of the world".

Sounds familiar. But, it actually refers to Kawasaki disease, which is a childhood heart disease.

Redo et al. [1] report an association between KD and wind patterns.

A follow up piece [2] describes how a plane equipped with filters was flown into likely looking air in a search for the culprit.

Reference

[1] "Association of Kawasaki disease with tropospheric wind patterns"
Xavier Rodó,Joan Ballester,Dan Cayan,Marian E. Melish,Yoshikazu Nakamura,Ritei Uehara & Jane C. Burns
Scientific Reports 1,Article number:152, 2011
http://www.nature.com/srep/2011/1111...srep00152.html

[2] http://www.nature.com/news/infectiou...e-wind-1.10374

John

certainly is thought provoking, at the very least. not quite climate or weather but could not find johnt's original post.

Attached Thumbnails

 

Does exposure to atmospheric metal pollution increase the chances of getting PD?

Palacios et al. [1] linked:
- Environmental Protection Agency Air Toxics data for "the following metals: arsenic, cadmium, chromium, lead, manganese, mercury and nickel, as well as total metal exposure"
- health data from a prospective study of female nurses with 540 cases of PD.

They found:
"Adulthood ambient exposure to the metals examined in this study does not appear to influence risk of PD disease."

Reference

[1] "E-002: Exposure to Airborne Metals and risk of Parkinson Disease in a Prospective Study of US Women"
Palacios, Natalia; Roberts, Andrea; Weisskopf, Marc; Schwarzschild, Michael; Laden, Francine; Ascherio, Alberto
Epidemiology. 23(5S):, September 2012.
doi: 10.1097/01.ede.0000416602.63176.b5
http://journals.lww.com/epidem/Citat...risk_of.3.aspx

John