Vitamin E intake, {alpha}-tocopherol status, and pancreatic cancer in a cohort of male smokers.
Nutritional Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department Health Human Services, Rockville, MD.
BACKGROUND: Evidence indicates that vitamin E has anticarcinogenic properties for gastrointestinal cancers; however, few studies have examined this with respect to exocrine pancreatic cancer. OBJECTIVE: The objective was to examine whether vitamin E intake and serum alpha-tocopherol concentrations were prospectively associated with exocrine pancreatic cancer. DESIGN: We conducted a cohort analysis of prediagnostic vitamin E intake (4 tocopherols, 4 tocotrienols), serum alpha-tocopherol concentrations, and pancreatic cancer in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study of male Finnish smokers aged 50-69 y at baseline. During follow-up from 1985 to 2004 (maximum: 19.4; median: 16 y), 318 incident cases were diagnosed among cohort participants with complete serum samples (n = 29,092); 306 cases had complete dietary data (n = 27,111). Cox proportional hazards models adjusted for age, smoking history, history of diabetes mellitus, and/or serum cholesterol were used to calculate hazard ratios (HRs) and 95% CIs. RESULTS: Higher alpha-tocopherol concentrations were associated with lower pancreatic cancer risk (highest compared with lowest quintile, HR: 0.52; 95% CI: 0.34, 0.80; P for trend = 0.03; continuous HR: 0.91; 95% CI: 0.84, 0.99). Polyunsaturated fat, a putative prooxidant nutrient, modified the association such that the inverse alpha-tocopherol association was most pronounced in subjects with a high polyunsaturated fat intake, ie, >9.9 g/d) highest compared with lowest quintile, HR: 0.38; 95% CI: 0.20, 0.70; P for trend = 0.03; continuous HR: 0.86; 95% CI: 0.75, 0.97; P for interaction = 0.05 and 0.02, respectively). No associations were observed for dietary tocopherols and tocotrienols. CONCLUSION: Our results support the hypothesis that higher alpha-tocopherol concentrations may play a protective role in pancreatic carcinogenesis in male smokers.
PMID: 19116326 [PubMed - as supplied by publisher]