Risk of Pancreatic Cancer May Be Reduced by Better Diet
In a study reported in the Journal of the National Cancer Institute, Hannah Arem, MHS, PhD, of the National Institutes of Health, and colleagues analyzed the association between quality of diet according to the 2005 Dietary Guidelines for Americans—Healthy Eating Index 2005 (HEI-2005) and risk for pancreatic cancer. They found that higher-quality diet was associated with reduced risk.
Study Details
The HEI-2005 scores for 537,218 men and women in the National Institutes of Health–American Association of Retired Persons Diet and Health Study were calculated using responses to food frequency questionnaires returned in 1995 and 1996. The HEI-2005 consists of 12 components, including the 9 adequacy components of total fruit, whole fruit, total vegetables, dark green and orange vegetables and legumes, total grains, whole grains, milk (including soy beverages), meat and beans, and healthy oils and the 3 moderation components of saturated fat, sodium, and calories from solid fat, alcohol, and added sugar.
Risk of pancreatic cancer was calculated according to HEI-2005 quintiles, with quintile 5 containing subjects who met the most dietary guidelines and quintile 1 containing those who met the fewest.
Reduced Risk
After median follow-up of 10.5 years, 2,383 cases of incident, exocrine pancreatic cancer were identified. On multivariate analysis adjusting for daily caloric intake, sex, diabetes, body mass index (BMI), and smoking status, subjects in quintile 5 had a significant 15% reduction in risk for cancer compared with subjects in quintile 1 (adjusted hazard ratio [HR] = 0.85, 95% confidence interval [CI] = 0.74–0.97, P = .003 for trend). For quartile 5 vs quartile 1, risk was significantly reduced in men (adjusted HR = 0.83, 95% CI = 0.70–0.98, P = .008 for trend) but not in women, although the magnitude of reduction was similar (adjusted HR = 0.87, 95% CI = 0.70–1.09, P = .16 for trend).
Test results for interaction between the HEI-2005 score and smoking or diabetes were not significant, and analyses restricted to those who did not smoke or those without diabetes yielded results similar to the main analysis. Sensitivity analyses excluding subjects diagnosed within 4 years of baseline or heavy alcohol consumers (≥ 3 drinks per day) did not change the hazard ratios, and excluding alcohol from the HEI-2005 score and adjusting for it as a separate variable did not change results. Adjustments for folate, red meat intake, and multivitamin use also yielded similar results.
Association With Body Mass Index
Analyses stratified by BMI of 18.5 to < 25 kg/m2 or 25 to 50 kg/m2 showed a significant interaction with HEI-2005 score in men (P = .03 for interaction) but not in women (P = .24 for interaction). For quintile 5 vs quintile 1, risk was nonsignificantly increased in those with lower BMI (HR = 1.21, 95% CI = 0.88–1.67) and significantly reduced in those with higher BMI (HR = 0.72, 95% CI = 0.59–0.88).
Among the individual components of the HEI-2005, small but significant reductions in risk were associated with milk product intake in men and dark-green and orange vegetables and legumes, total grains, and healthy oils intake in women.
The investigators concluded, “Our findings support the hypothesis that consuming a high-quality diet, as scored by the HEI-2005, may reduce the risk of pancreatic cancer.”
The study was supported in part by the National Cancer Institute.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
