Latitude variation in pancreatic cancer mortality in Australia.
OBJECTIVE
Ecological studies support the hypothesis that there is an association between vitamin D and pancreatic cancer (PaCa) mortality, but observational studies are somewhat conflicting. We sought to contribute further data to this issue by analyzing the differences in PaCa mortality across the eastern states of Australia and investigating if there is a role of vitamin D-effective ultraviolet radiation (DUVR), which is related to latitude.


METHODS
Mortality data from 1968 to 2005 were sourced from the Australian General Record of Incidence and Mortality books. Negative binomial models were fitted to calculate the association between state and PaCa mortality. Clear sky monthly DUVR in each capital city was also modeled.


RESULTS
Mortality from PaCa was 10% higher in southern states than in Queensland, with those in Victoria recording the highest mortality risk (relative risk, 1.13; 95% confidence interval, 1.09-1.17). We found a highly significant association between DUVR and PaCa mortality, with an estimated 1.5% decrease in the risk per 10-kJ/m increase in yearly DUVR.


CONCLUSIONS
These data show an association between latitude, DUVR, and PaCa mortality. Although this study cannot be used to infer causality, it supports the need for further investigations of a possible role of vitamin D in PaCa etiology.
Neale
Rachel E
RE
Cancer and Population Studies, Queensland Institute of Medical Research, Brisbane, Australia. rachel.neale@qimr.edu.au
Youlden
Danny R
DR
Krnjacki
Lauren
L
Kimlin
Michael G
MG
van der Pols
Jolieke C
JC
D000328:Adult; D005260:Female; D005843:Geography; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009026:Mortality; D009517:New South Wales / Q000453:epidemiology; D010190:Pancreatic Neoplasms / Q000453:epidemiology / Q000401:mortality*; D011793:Queensland / Q000453:epidemiology; D012042:Registries / Q000706:statistics & numerical data*; D012307:Risk Factors; D012621:Seasons; D013648:Tasmania / Q000453:epidemiology; D014466:Ultraviolet Rays; D014739:Victoria / Q000453:epidemiology; D014807:Vitamin D / Q000097:blood
D014807:Vitamin D