Background:

The epidemiological evidence on possible relationships between coffee consumption and prostate cancer (PCa) risk by subtype of the disease (localized, advanced) and fatal PCa risk is limited.

Materials and methods:

A population-based cohort of 44 613 Swedish men aged 45–79 years was followed up from January 1998 through December 2010 for incidence of localized (n = 2368), advanced (n = 918) and fatal (n = 515) PCa. We assessed the associations between coffee consumption and localized, advanced and fatal PCa risk using competing-risk regressions. We examined possible effect modification by body mass index (BMI).

Results:

For localized PCa, each one cup increase in daily coffee consumption was associated with a 3% reduced risk [sub-hazard ratio (SHR) = 0.97, 95% confidence interval (CI) = 0.95–0.99]. For advanced and fatal PCa, we found a non-significant inverse association; each one cup increase was associated with a 2% reduced risk of advanced [SHR (95% CI) = 0.98 (0.95–1.02)] and fatal PCa [SHR (95% CI) = 0.98 (0.93–1.03)]. We observed evidence of effect, modification by BMI for localized PCa (Pinteraction = 0.03); the inverse association was stronger among overweight and obese men (BMI ≥ 25 kg/m2) compared with normal-weight men (BMI < 25 kg/m2).

Conclusions:

We observed a clear inverse association between coffee consumption and risk of localized PCa, especially among overweight and obese men.