Purpose: Evidence on the association between coffee consumption and prostate cancer risk is inconsistent; furthermore, few studies have examined the relationship between coffee consumption and fatal prostate cancer. The aim of this study was to investigate whether coffee intake is associated with the risk of overall and fatal prostate cancer.
Methods: We conducted a prospective analysis among 288,391 men in the National Institutes of Health AARP Diet and Health Study who were between 50 and 71 years old at baseline in 1995-1996. Coffee consumption was assessed at baseline. Cox proportional hazards models were used to calculate the age- and multivariable-adjusted hazard ratios (HR)s and 95 % confidence intervals (CIs).
Results: Over 11 years of follow-up, 23,335 cases of prostate cancer were ascertained, including 2,927 advanced and 917 fatal cases. Coffee consumption was not significantly associated with prostate cancer risk. The multivariable-adjusted HRs (95 % CI), comparing those who drank six or more cups per day to nondrinker, were as follows: 0.94 (0.86-1.02), p trend = 0.08 for overall prostate cancer, 1.13 (0.91-1.40), p trend = 0.62 for advanced prostate cancer, and 0.79 (0.53-1.17), p trend = 0.20 for fatal prostate cancer. The findings remained nonsignificant when we stratified by prostate-specific antigen testing history or restricted to nonsmokers.
Conclusions: We found no statistically significant association between coffee consumption and the risk of overall, advanced, or fatal prostate cancer in this cohort, though a modest reduction in risk could not be excluded.