Background: Body size has been hypothesized to influence the risk of
prostate cancer; however, most epidemiologic studies have relied on body
mass index (BMI) to assess adiposity, whereas only a few studies have
examined whether body fat distribution predicts prostate cancer.
Methods: We examined the association of height, BMI, waist and hip
circumference, and waist-hip ratio with prostate cancer risk among
129,502 men without cancer at baseline from 8 countries of the European
Prospective Investigation into Cancer and Nutrition (EPIC), using Cox
regression, with age as time metric, stratifying by study center and age
at recruitment, and adjusting for education, smoking status, alcohol
consumption, and physical activity.
Results: During a mean follow-up of 8.5 years, 2,446 men developed
prostate cancer. Waist circumference and waist-hip ratio were positively
associated with risk of advanced disease. The relative risk of advanced
prostate cancer was 1.06 (95% confidence interval, 1.01-1.1) per
5-cm-higher waist circumference and 1.21 (95% confidence interval,
1.04-1.39) per 0.1-unit-higher waist-hip ratio. When stratified by BMI,
waist circumference and waist-hip ratio were positively related to risk
of total, advanced, and high-grade prostate cancer among men with lower
but not among those with higher BMI (P-interaction for waist with BMI,
0.25, 0.02, and 0.05, respectively; P-interaction for waist-hip ratio
with BMI, 0.27, 0.22, and 0.14; respectively).
Conclusions: These data suggest that abdominal adiposity may be
associated with an increased risk of advanced prostate cancer. This
association may be stronger among individuals with lower BMI; however,
this finding needs confirmation in future studies. (Cancer Epidemiol
Biomarkers Prev 2008;17(11):3252-61