Obesity Poses Greater Prostate Cancer Risk for African American vs White Men
In an analysis of participants in the SELECT prevention trial reported in JAMA Oncology, Barrington et al found that obesity in African American men was associated with a greater risk of prostate cancer than in white men. African American men have the highest prostate cancer incidence and mortality in the United States.
The study involved findings in 3,398 African American and 22,673 white men who participated in the Selenium and Vitamin E Cancer Prevention Trial (SELECT; 2001–2011), with the current analysis being completed in 2014.
Cancer Risk
The median follow-up was 5.6 years. Body mass index (BMI) was positively associated with an increased risk of prostate cancer among African American men (hazard ratio [HR] = 1.49, 95% confidence interval [CI] = 0.95–2.34 for ≥ 35 vs < 25 kg/m2; P = .03 for trend) but not among white men. Hazard ratios associated with African American race increased from 1.28 (95% CI = 0.91–1.80) among men with a BMI < 25 kg/m2 to 2.03 (95% CI = 1.38–2.98) among those with a BMI ≥ 35 kg/m2 (P = .03 for trend).
By Grade
BMI was inversely associated with low-grade prostate cancer risk among white men (HR = 0.80, 95% CI = 0.58–1.09, for ≥ 35 vs < 25 kg/m2; P = .02 for trend) and positively associated with risk among African American men (HR = 2.22, 95% CI = 1.17–4.21; P = .05 for trend). BMI was positively associated with risk of high-grade prostate cancer in both white men (HR = 1.33, 95% CI = 0.90–1.97, for ≥ 35 vs < 25 kg/m2; P = .01 for trend) and African American men (HR = 1.81, 95% CI = 0.79–4.11; P = .02 for trend).
The investigators concluded: “Obesity is more strongly associated with increased prostate cancer risk among African American than non-Hispanic white men, and reducing obesity among African American men could reduce the racial disparity in cancer incidence. Additional research is needed to elucidate the mechanisms underlying the differential effects of obesity in African American and non-Hispanic white men.”
Wendy E. Barrington, PhD, of University of Washington School of Nursing, is the corresponding author of the JAMA Oncology article.
The study was supported by a grant from the National Cancer Institute; SELECT was funded by grants from the National Cancer Institute and National Center for Complementary and Alternative Medicine of the National Institutes of Health.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
