prostate cancer and diabetes

Last edited 12/2023

  • among men of European ancestry, diabetics have a lower risk of prostate cancer than do nondiabetics
    • biologic basis of this association is unknown
    • a population-based prospective study included 5,941 prostate cancer cases identified over a 12-year period (1993-2005) among 86,303 European-American, African-American, Latino, Japanese-American, and Native Hawaiian men from the Multiethnic Cohort
      • association between diabetes and prostate-specific antigen (PSA) levels (n = 2,874) and PSA screening frequencies (n = 46,970) was also examined
      • diabetics had significantly lower risk of prostate cancer than did nondiabetics (relative risk = 0.81, 95% confidence interval (CI): 0.74, 0.87; P < 0.001), with relative risks ranging from 0.65 (95% CI: 0.50, 0.84; P = 0.001) among European Americans to 0.89 (95% CI: 0.77, 1.03; P = 0.13) among African Americans
      • mean PSA levels were significantly lower in diabetics than in nondiabetics (mean PSA levels, 1.07 and 1.28, respectively; P = 0.003) as were PSA screening frequencies (44.7% vs. 48.6%; P < 0.001); however, this difference could explain only a small portion ( approximately 20%) of the inverse association between these diseases
    • the study authors concluded that diabetes is a protective factor for prostate cancer across populations, suggesting shared risk factors that influence a common mechanism.

A meta-analysis found an inverse association between diabetes mellitus and prostate cancer [RR, 0.84] (2)

  • for cohort studies alone, the RR was 0.81

Jo et al showed a negative association with prostate cancer relating to duration of metformin treatment (3):

  • prostate cancer risk decreased with increasing duration of metformin administration

Reference:

Related pages:

prostate cancer