Dietary Fiber Intake and Risk of Advanced and Aggressive Forms of Prostate Cancer: A Pooled Analysis of 15 Prospective Cohort Studies

Elkhansa Sidahmed; Stephen J Freedland; Molin Wang; Kana Wu; Demetrius Albanes; Matt Barnett; Piet A van den Brandt; Michael B Cook; Graham G Giles; Edward Giovannucci; Christopher A Haiman; Susanna C Larsson; Timothy J Key; Erikka Loftfield; Satu Männistö; Marjorie L McCullough; Roger L Milne; Marian L Neuhouser; Elizabeth A Platz; Aurora Perez-Cornago; Norie Sawada; Jeannette M Schenk; Rashmi Sinha; Shoichiro Tsugane; Kala Visvanathan; Ying Wang; Kami K White; Walter C Willett; Alicja Wolk; Regina G Ziegler; Jeanine M Genkinger; Stephanie A Smith-Warner

doi:10.1016/j.jand.2024.04.006

Dietary Fiber Intake and Risk of Advanced and Aggressive Forms of Prostate Cancer: A Pooled Analysis of 15 Prospective Cohort Studies

J Acad Nutr Diet. 2024 Apr 16:S2212-2672(24)00163-1. doi: 10.1016/j.jand.2024.04.006. Online ahead of print.

Authors

Elkhansa Sidahmed¹, Stephen J Freedland², Molin Wang³, Kana Wu⁴, Demetrius Albanes⁵, Matt Barnett⁶, Piet A van den Brandt⁷, Michael B Cook⁸, Graham G Giles⁹, Edward Giovannucci¹⁰, Christopher A Haiman¹¹, Susanna C Larsson¹², Timothy J Key⁸, Erikka Loftfield⁵, Satu Männistö¹³, Marjorie L McCullough¹⁴, Roger L Milne⁹, Marian L Neuhouser¹⁵, Elizabeth A Platz¹⁶, Aurora Perez-Cornago⁸, Norie Sawada¹⁷, Jeannette M Schenk⁶, Rashmi Sinha⁵, Shoichiro Tsugane¹⁷, Kala Visvanathan¹⁶, Ying Wang¹⁸, Kami K White¹⁹, Walter C Willett¹⁰, Alicja Wolk²⁰, Regina G Ziegler⁵, Jeanine M Genkinger²¹, Stephanie A Smith-Warner²²

Affiliations

¹ Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts.
² Department of Urology, Cedars-Sinai Medical Center, Los Angeles, California; Urology Section, Durham Veterans Affairs Medical Center, Durham, North Carolina.
³ Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
⁴ Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, Massachusetts (at time work completed); Vertex Pharmaceuticals, Boston, Massachusetts (current).
⁵ Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland.
⁶ Division of Public Health Sciences, Fred Hutchinson Cancer Center, Seattle, Washington.
⁷ Department of Epidemiology, GROW-School for Oncology and Developmental Biology, Maastricht University, Maastricht, The Netherlands.
⁸ Nuffield Department of Population Health, University of Oxford, Oxford, UK.
⁹ Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Victoria, Australia; Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria, Australia; Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia.
¹⁰ Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts.
¹¹ Department of Preventive Medicine, Keck School of Medicine and Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California.
¹² Unit of Cardiovascular and Nutritional Epidemiology, Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden; Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
¹³ Department of Public Health and Welfare, Finnish Institute for Health and Welfare, Helsinki, Finland.
¹⁴ Department of Population Science, American Cancer Society, Kennesaw, Georgia.
¹⁵ Cancer Prevention Program, Division of Public Health Sciences Fred Hutchinson Cancer Center, Seattle, Washington.
¹⁶ Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
¹⁷ Division of Cohort Research, National Cancer Center Institute for Cancer Control, Tokyo, Japan.
¹⁸ Department of Population Science, American Cancer Society, Atlanta, Georgia.
¹⁹ Epidemiology Program, University of Hawaii Cancer Center, Honolulu, Hawaii.
²⁰ Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden; Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
²¹ Department of Epidemiology, Mailman School of Public Health and Herbert Irving Comprehensive Cancer Center, Columbia University, New York, New York.
²² Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, Massachusetts; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts. Electronic address: swarner@hsph.harvard.edu.

PMID: 38636793
DOI: 10.1016/j.jand.2024.04.006

Abstract

Background: Evidence of an association between dietary fiber intake and risk of advanced and aggressive forms of prostate cancer (PC) and PC mortality is limited.

Objective: The aim of this study was to examine associations between intakes of dietary fiber overall and by food source and risk of advanced and aggressive forms of PC.

Design: The study design was a pooled analysis of the primary data from 15 cohorts in 3 continents. Baseline dietary fiber intake was assessed using a validated food frequency questionnaire or diet history in each study.

Participants/setting: There were 842 149 men followed for up to 9 to 22 years between 1985 and 2009 across studies.

Main outcome measures: The primary outcome measures were advanced (stage T4, N1, or M1 or PC mortality), advanced restricted (excluded men with missing stage and those with localized PC who died of PC), and high-grade PC (Gleason score ≥8 or poorly differentiated/undifferentiated) and PC mortality.

Statistical analysis performed: Study-specific multivariable hazard ratios (MVHR) were calculated using Cox proportional hazards regression and pooled using random effects models.

Results: Intake of dietary fiber overall, from fruits, and from vegetables was not associated with risk of advanced (n = 4863), advanced restricted (n = 2978), or high-grade PC (n = 9673) or PC mortality (n = 3097). Dietary fiber intake from grains was inversely associated with advanced PC (comparing the highest vs lowest quintile, MVHR 0.84; 95% CI 0.76-0.93), advanced restricted PC (MVHR 0.85; 95% CI 0.74-0.97), and PC mortality (MVHR 0.78; 95% CI 0.68-0.89); statistically significant trends were noted for each of these associations (P ≤ .03), and a null association was observed for high-grade PC for the same comparison (MVHR 1.00; 95% CI 0.93-1.07). The comparable results were 1.06 (95% CI 1.01-1.10; P value, test for trend = .002) for localized PC (n = 35,199) and 1.05 (95% CI 0.99-1.11; P value, test for trend = .04) for low/intermediate grade PC (n = 34 366).

Conclusions: Weak nonsignificant associations were observed between total dietary fiber intake and risk of advanced forms of PC, high-grade PC, and PC mortality. High dietary fiber intake from grains was associated with a modestly lower risk of advanced forms of PC and PC mortality.

Keywords: Cohort studies; Dietary fiber; Grains; Pooled analysis; Prostate cancer.