Dietary Vitamin K Intake and the Risk of Pancreatic Cancer: A Prospective Study of 101,695 American Adults
Dao-Wu Yu, Qu‐Jin Li, Long Cheng, Pengfei Yang, Weiping Sun, Yang Peng, Jie‐Jun Hu, Jingjing Wu, Jianping Gong, Guo‐Chao Zhong
Abstract
No epidemiologic studies have been conducted to assess the association of intake of dietary vitamin K with the risk of pancreatic cancer. We used prospective data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial between 1993 and 2009 to fill this gap. A total of 101,695 subjects were identified. Dietary intakes of phylloquinone (vitamin K1), menaquinones (vitamin K2), and dihydrophylloquinone (dihydrovitamin K1) were assessed using a food frequency questionnaire. Cox regression was applied to calculate hazard ratios and 95% confidence intervals. During a mean follow-up of 8.86 years (900,744.57 person-years), 361 cases of pancreatic cancer were documented. In the fully adjusted model, dietary intakes of phylloquinone (for quartile 4 vs. quartile 1, hazard ratio (HR) = 0.57, 95% confidence interval (CI): 0.39, 0.83; P for trend = 0.002) and dihydrophylloquinone (for quartile 4 vs. quartile 1, HR = 0.59; 95% CI: 0.41, 0.85; P for trend = 0.006), but not menaquinones (for quartile 4 vs. quartile 1, HR = 0.93; 95% CI: 0.65, 1.33; P for trend = 0.816), were found to be inversely associated with the risk of pancreatic cancer in a nonlinear dose-response manner (all P values for nonlinearity < 0.05), and this was not modified by predefined stratification factors and remained in sensitivity analyses. In conclusion, dietary intakes of phylloquinone and dihydrophylloquinone, but not menaquinones, confer a lower risk of pancreatic cancer. Future studies should confirm our findings.