Fasting blood glucose and the risk of all-cause mortality in patients with diabetes mellitus undergoing hemodialysis

Background: Glycemic control is particularly important in hemodialysis (HD) patients with diabetes mellitus (DM). Although fasting blood glucose (FBG) level is an important indicator of glycemic control, a clear target for reducing mortality in HD patients with DM is lacking. Methods: A total of 26,162 maintenance HD patients with DM were recruited from the National Health Insurance Database of Korea between 2002 and 2018. We analyzed the association of FBG levels at the baseline health examination with the risk of all-cause and cause-specific mortality. Results: Patients with FBG 80–100 mg/dL showed a higher survival rate compared with that of other FBG categories (p < 0.001). The risk of all-cause mortality increased with the increase in FBG levels, and adjusted hazard ratios (HRs) were 1.10 (95% confidence interval [CI], 1.04–1.17), 1.21 (95% CI, 1.13–1.29), 1.36 (95% CI, 1.26–1.46), and 1.61 (95% CI, 1.51–1.72) for patients with FBG 100–125, 125–150, 150–180, and ≥180 mg/dL, respectively. The HR for mortality was also significantly increased in patients with FBG <80 mg/dL (adjusted HR, 1.14; 95% CI, 1.05–1.23). The analysis of cause-specific mortality also revealed a J-shaped curve between FBG levels and the risk of cardiovascular deaths. However, the risk of infection or malignancy-related deaths was not linearly increased as FBG levels increased. Conclusion: A J-shaped association was observed between FBG levels and the risk of all-cause mortality, with the lowest risk at FBG 80–100 mg/dL in HD patients with DM.