Metformin lowers prostate cancer incidence and risk of recurrence: Study

A new study by the team led by Yuchen Liu unveiled that the use of metformin and a lower incidence of prostate cancer (PCa) were independently correlated. The findings of this study were published in the recent issue of Prostate Cancer and Prostatic Diseases journal.

Metformin serves as an oral biguanide that is used as the first line of therapy for type 2 diabetes and reduces hepatic glucose synthesis while increasing insulin sensitivity and glucose uptake by peripheral tissues. Studies have shown that metabolic syndrome is linked to an increased risk of PCa development and progression. As such, metformin has been the subject of several population-based epidemiological research and has been regarded as a possible anti-PCa drug. However, there has been contradictory research in the past about the link between metformin use and the risk of developing prostate cancer. Thus, this study was set out to investigate any potential dose-response relationships and evaluate the impact of metformin on clinical outcomes in PCa patients.

A meticulous search of the existing literature was done using four registries and ten internet databases. To evaluate the impact of metformin on the risk of PCa, the combined relative risks (RRs) were computed using a random-effects model with 95% confidence intervals (CIs). Also, the sensitivity studies and pertinent subgroup analysis were also carried out in this study.

The results of many studies analyzed in this research indicated that using metformin is linked to a decreased incidence of PCa (RR: 0.82, 95% CI: 0.74–0.91). Despite the results were not statistically significant, using metformin was observed to minimize the risk of PCa recurrence (RR: 0.97, 95% CI: 0.81–1.15). However, the usage of metformin did not correlate with death from PCa (RR: 0.94, 95% CI: 0.81–1.09).

The subgroup analysis revealed that the investigation included participants from Asia and Europe, and the incidence of PCa was lowered by using metformin. It was discovered that the length of metformin treatment and its preventive effect were correlated linearly.

Overall, this meta-analysis found an independent relationship between metformin usage and a lower incidence of PCa. The use of metformin was not linked to mortality or risk of PCa recurrence. Also, the study uncovered that the length of time taken on metformin affected the occurrence of PCa.

Reference:

Liu, Y., Zhang, Q., & Huang, X. (2024). Effect of metformin on incidence, recurrence, and mortality in prostate cancer patients: integrating evidence from real-world studies. In Prostate Cancer and Prostatic Diseases. Springer Science and Business Media LLC. https://doi.org/10.1038/s41391-024-00871-7