Association of baseline inflammatory biomarkers with cancer mortality in the REGARDS cohort

// Tomi Akinyemiju 1 , Justin X. Moore 2 , Maria Pisu 3 , Michael Goodman 4 , Virginia J. Howard 5 , Monika Safford 6 , Susan C. Gilchrist 7 , Mary Cushman 8 , LeAnn Long 9 and Suzanne E. Judd 9 1 Department of Population Health Sciences, Duke University School of Medicine, Durham, NC, USA 2 Division of Public Health Sciences and Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA 3 Division of Preventive Medicine, University of Alabama at Birmingham, Birmingham AL, USA 4 Department of Epidemiology, Emory University Rollins School of Public Health, Atlanta, GA, USA 5 Department of Epidemiology, University of Alabama at Birmingham, Birmingham AL, USA 6 Department of Medicine, Weill Cornell Medical College, New York, NY, USA 7 Department of Clinical Cancer Prevention and Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA 8 Department of Medicine and Vermont Cancer Center, Larn er College of Medicine at the University of Vermont, Burlington, VT, USA 9 Department of Biostatistics, University of Alabama at Birmingham, Birmingham, AL, USA Correspondence to: Tomi Akinyemiju, email: tomi.akinyemiju@duke.edu Keywords: inflammatory biomarkers; racial disparities; cancer mortality; obesity Received: December 12, 2018     Accepted: June 29, 2019     Published: August 06, 2019 ABSTRACT This study examines the association between inflammatory biomarkers and risk of cancer mortality by race. Data were obtained from 1,856 participants in the prospective REGARDS cohort who were cancer-free at baseline, and analyzed in relation to cancer mortality prospectively. Biomarkers were log-transformed and categorized into tertiles due to non-normal distributions, and Cox proportional hazard regression models were utilized to compute hazard ratios with 95% confidence intervals using robust sandwich methods. Individuals in the highest tertile of IL-6 had over a 12-fold increased risk of cancer mortality (HR: 12.97, 95% CI: 3.46–48.63); those in the highest tertile of IL-8 had over a 2-fold increased risk of cancer mortality (HR: 2.21, 95% CI: 0.86–5.71), while those in the highest tertile of IL-10 had over a 3-fold increased risk of cancer mortality (HR: 3.06, 95% CI: 1.35–6.89). In race-stratified analysis, each unit increase in IL-6 was associated with increased risk of cancer mortality among African-Americans (HR: 3.88, 95% CI: 1.17–12.88) and Whites (5.25, 95% CI: 1.24–22.31). If replicated in larger, racially diverse prospective cohorts, these results suggest that cancer patients may benefit from clinical or lifestyle approaches to regulate systemic inflammation as a cancer prevention strategy.