Just found this. It has some fascinating maps of PC distribution by county in the U.S. Correlations between meteorological parameters and prostate cancer.
Int J Health Geogr. 2010 Apr 21;9:19.
St-Hilaire S, Mannel S, Commendador A, Mandal R, Derryberry D.
Department of Biological Sciences, Idaho State University, Pocatello, ID 83209, USA. email@example.com
BACKGROUND: There exists a north-south pattern to the distribution of prostate cancer in the U.S., with the north having higher rates than the south. The current hypothesis for the spatial pattern of this disease is low vitamin D levels in individuals living at northerly latitudes; however, this explanation only partially explains the spatial distribution in the incidence of this cancer. Using a U.S. county-level ecological study design, we provide evidence that other meteorological parameters further explain the variation in prostate cancer across the U.S.VIEW IMAGE
of PC distribution across the U.S.
RESULTS: In general, the colder the temperature and the drier the climate in a county, the higher the incidence of prostate cancer, even after controlling for shortwave radiation, age, race, snowfall, premature mortality from heart disease, unemployment rate, and pesticide use. Further, in counties with high average annual snowfall (>75 cm/yr) the amount of land used to grow crops (a proxy for pesticide use) was positively correlated with the incidence of prostate cancer.
CONCLUSION: The trends found in this USA study suggest prostate cancer may be partially correlated with meteorological factors. The patterns observed were consistent with what we would expect given the effects of climate on the deposition, absorption, and degradation of persistent organic pollutants including pesticides. Some of these pollutants are known endocrine disruptors and have been associated with prostate cancer.
I checked all the journal articles on vitamin D and PC that were published in 2010. The picture is decidedly mixed; different research points different ways. There is fairly strong evidence that Vitamin D reduces PC in a lab setting (in vitro) but much less impact if any on studies with actual patients (in vivo). Basically there are two explanations offered for the discrepancy. (1) In seems that the way the body processes vitamin D is closely related to how the body processes androgen. So that low levels of vitamin D may not be causing PC, but rather they may be the result of something else that is causing PC. As a result, increasing the levels of vitamin D does not seem to have that much effect. (2) Although in the lab, Vitamin D is effective, it is very hard to get the level of vitamin D in the blood up safely to the high concentrations that work in the lab.
You can read the whole article free here: www.ncbi.nlm.nih.gov/pmc/articles/PMC2873568/pdf/1476-072X-9-19.pdf
Post Edited (proscapt) : 12/13/2010 7:09:33 PM (GMT-7)