Spironolactone use tied to lower risk for prostate cancer

Takeaway

• Spironolactone use was associated with a lower risk for prostate cancer (PCa).
• Risk reduction was greater in current users than past users and the risk decreased with increasing dose.

Why this matters

• Findings warrant future studies to determine the chemotherapeutic effects of spironolactone.

Study design

• A population-wide, case-control study included 31,591 men with PCa (cases) and 156,802 age- and county-matched men without PCa (controls).
• Funding: None disclosed.

Key results

• In multivariable analyses, spironolactone vs control group had a lower risk for PCa (OR, 0.83; 95% CI, 0.76-0.89).
• Risk reduction was higher in current users (OR, 0.77; 95% CI, 0.69-0.86) than past users (OR, 0.88; 95% CI, 0.79-0.97) and the risk decreased with increasing dose (P_trend<.001).
• Spironolactone use was linked with lower risk for PCa across all grade, prostate-specific antigen (PSA) categories and risk groups:
  • Grade:
    • 1 (OR, 0.79; 95% CI, 0.68-0.92);
    • 2 (OR, 0.86; 95% CI, 0.73-1.00);
    • 3 (OR, 0.68; 95% CI, 0.55-0.84); and
    • 4 (OR, 0.85; 95% CI, 0.68-1.06).
  • PSA categories (in ng/ml):
    • <3 (OR, 0.74; 95% CI, 0.50-1.11);
    • 3 to <10 (OR, 0.88; 95% CI, 0.78-1.00);
    • 10 to <20 (OR, 0.77; 95% CI, 0.65-0.93);
    • 20 to <50 (OR, 0.86; 95% CI, 0.71-1.04); and
    • 50+ (OR, 0.88; 95% CI, 0.73-1.05).
  • Risk groups:
    • low (OR, 0.85; 95% CI, 0.70-1.02);
    • intermediate (OR, 0.82; 95% CI, 0.71-0.95);
    • high (OR, 0.78; 95% CI, 0.67-0.91); and
    • advanced/metastatic (OR, 0.92; 95% CI, 0.79-1.07).

Limitation

• Lack of data on potential confounders such as body weight and other health behaviours.