Kristensen KB, et al. – Given that prior research has suggested a reduction in the risk of prostate cancer with the use of vitamin K antagonists (VKAs), researchers conducted a nested case-control study using Danish demographic and health data registries, and summarized existing evidence in a meta-analysis. Participants included all Danish mean 40-85 years of age with incident histologically verified prostate adenocarcinoma between 2005 and 2015 (cases), amounting to 38,832 eligible prostate cancer cases. Ten age-matched control participants were identified and selected for each case. Of the cases included, 1,089 (2.8%) had used VKAs for ≥ 3 years. The researchers adjusted for concomitant drug use, medical history, and socioeconomic status. They found that VKA use did not attenuate the risk of prostate cancer in this patient population. In combination with the previous study findings, these results indicated that VKAs may not have a significant protective effect against prostate cancer.