Abstract 4648: Insulinemic and inflammatory dietary patterns and risk of prostate cancer

Abstract

Abstract Background: Studies of diet and prostate cancer have primarily focused on individual dietary factors, often with null or mixed findings. Assessment of dietary patterns is an alternative approach and has been increasingly used in nutritional epidemiology, providing the advantage of better accounting for added effects and interactions of dietary components. Hyperinsulinemia and inflammation are interrelated biological pathways that link diet with risk of several cancers, and studies have suggested that these may also increase prostate cancer risk. Whether dietary patterns based on these pathways contribute to the development and progression of prostate cancer is unclear. Methods: We followed 39,776 men in the Health Professionals Follow-up Study (1986-2014) to examine associations between two empirical hypothesis-oriented dietary patterns with risk of total, local, advanced, and fatal prostate cancer. The two dietary patterns - empirical dietary index for hyperinsulinemia (EDIH) and empirical dietary inflammatory pattern (EDIP) - were constructed using the weighted sum of food groups that predicted plasma C-peptide (EDIH) and inflammatory biomarkers (EDIP). Dietary scores were calculated from food frequency questionnaires at baseline and updated every 4 years. Multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression. Results: We documented 5,682 incident cases of total prostate cancer and 658 cases of fatal prostate cancer over 868,552 person-years of follow-up. In multivariable-adjusted models, men in the highest EDIH quintile had an 18% higher risk of advanced prostate cancer (HR: 1.18, 95% CI: 0.96-1.45; P=0.04 for trend) and a 24% higher risk of fatal prostate cancer (HR: 1.24, 95% CI: 0.96-1.59; P=0.03 for trend) compared to men in the lowest quintile. There were no significant associations for EDIP and prostate cancer risk. BMI did not modify the association for either dietary pattern. Conclusion: Hyperinsulinemia may be a potential mechanism linking dietary patterns and risk of aggressive prostate cancer. Additional studies to define mechanisms of action and interventions to reduce prostate cancer risk are warranted. Citation Format: Benjamin C. Fu, Fred K. Tabung, Claire H. Pernar, Weike Wang, Amparo G. Gonzalez-Feliciano, Ilkania M. Chowdhury-Paulino, Steven K. Clinton, Edmund Folefac, Mingyang Song, Adam S. Kibel, Edward L. Giovannucci, Lorelei A. Mucci. Insulinemic and inflammatory dietary patterns and risk of prostate cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4648.