Reason for higher pancreatic cancer rates in blacks still unclear
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.