Pancreatic cancer mortality rates have been higher among
blacks; however, the risk is not attributable to currently known and accepted
risk factors for the disease, such as smoking and obesity.
Previous findings from studies have shown blacks have a
higher rate of diagnosis and death due to pancreatic cancer than whites. To
assess whether risk factor patterns could explain these disparities,
researchers prospectively examined data from blacks and whites enrolled in the
American Cancer Societys Cancer Prevention Study (CPS II).
There were 6,243 pancreatic cancer-related deaths from
1984 to 2004. Blacks had an age-adjusted relative risk of 1.42 (95% CI,
1.28-1.58) for pancreatic cancer mortality compared with whites. Racial
variation was observed for two risk factors: smoking and BMI.
There was an elevated risk for pancreatic mortality in
blacks (HR=1.67; 95% CI, 1.28-2.18) and whites (HR=1.82; 95% CI, 1.7-1.95) who
were current smokers. The effect of smoking was comparable, despite the
fact that blacks smoked fewer cigarettes per day and for a shorter
duration, the researchers wrote.
Obesity was associated with pancreatic cancer-related
death in black men (HR=1.66; 95% CI, 1.05-2.63) and white men (HR=1.42; 95% CI,
1.25-1.60) and women (HR=1.37; 95% CI, 1.22-1.54), but not in black women. The
risk associated with smoking was 80% in white men vs. 56% in black men, and the
risk associated with obesity was 66% in black men vs. 42% in white men.
In the end, the researchers were unable to
attribute racial disparities in pancreatic cancer to smoking, diabetes, family
history, BMI and cholecystectomy, they wrote. The inability to
attribute excess risk of disease in blacks to currently accepted or speculative
risk factors points to other, yet to be determined, etiologic factors that play
a role in the disease process.
Arnold LD. Cancer Epidemiol Biomarkers Prev.