Diabetes Lowers PSA Levels but the Difference Is Too Small to Affect Cancer Detection
A meta-analysis of 13 studies found that men with diabetes have statistically significantly lower PSA levels than non-diabetics, but the mean difference of just 0.07 ng/mL is clinically negligible. The authors conclude that diabetes-related PSA reduction is unlikely to meaningfully influence prostate cancer detection in screening settings, though disease duration, severity, and treatment may contribute to variation. The finding is reassuring for laboratories interpreting PSA results in diabetic patients.
The original study
Untangling the association between prostate-specific antigen and diabetes: a systematic review and meta-analysis.
- Authors
- Bernal-Soriano MC, Lumbreras B, Hernández-Aguado I, Pastor-Valero M, López-Garrigos M, Parker LA
- Journal
- Clinical chemistry and laboratory medicine
- Type
- Journal Article, Meta-Analysis, Systematic Review
- PMID
- 32681769
Original abstract
OBJECTIVES: Several studies have shown an inverse association between diabetes mellitus and prostate cancer (PCa). Some researchers suggest that this relationship is due to reduced PCa detection in diabetics due to lower prostate-specific antigen (PSA) levels compared to non-diabetics. Our objective is to analyze the impact of diabetes on PSA in asymptomatic men without known prostate pathology and without prior prostate intervention. METHODS: We searched Medline (via PubMed), Embase and Scopus. We included studies that reported the relationship between serum PSA levels and diabetes or diabetes treatment in asymptomatic adult men without known prostate pathology, and without prior prostate intervention. Pooled mean differences were compared between diabetics and non-diabetics. RESULTS: Of 2,392 screened abstracts, thirteen studies met the inclusion criteria and 8 (62%) reported appropriate measures that could be included in a meta-analysis. Eleven (85%) examined the influence of diabetes on PSA levels and 8 (62%) evaluated the influence of diabetes treatments on PSA levels. Overall diabetics had a significantly lower PSA level compared to non-diabetics (mean difference: -0.07 ng/mL; 95% CI -0.10, -0.04). CONCLUSIONS: Diabetes and related factors (such as disease duration, severity and treatment) were significantly associated with lower PSA levels among asymptomatic men, yet differences were small and are unlikely to influence PCa detection in a screening setting.