When we combined all above definitions of worsening control of diabetes, we found a positive association between use of GnRH and diabetes control (HR: 1.24, 95% CI: 1.13–1.34), compared with men without PCa, but no increased risk was seen for those with PCa not using GnRH (HR: 0.98, 95%CI: 0.93–1.03) (Table 2). This evidence concerns the gene GNRH1 and diabetes mellitus.