Associations of Estimated Glomerular Filtration Rate with All-Cause Mortality and Cardiovascular Mortality in Patients with Diabetic Foot Osteomyelitis

AIM: The purpose of this study was to explore the association between estimated glomerular filtration rate (eGFR) and clinical outcomes in patients with diabetic foot osteomyelitis (DFO). METHODS: This was a retrospective observational study. A total of 199 patients with DFO were recruited and divided into three groups by eGFR: normal kidney function group (eGFR ≥ 90), mildly decreased kidney function group (eGFR 60–89) and moderately to severely decreased kidney function group (eGFR < 60). The patients were followed-up for a median of 36 months, and the study outcomes were all-cause mortality and major cardiovascular adverse events (MACE). Cox proportional hazard models were used to assess the association between eGFR and the outcomes, and a stratified analysis by sex was conducted. RESULTS: During follow-up, all-cause mortality occurred in 51 (25.63%) patients among 199 participants, 54 (28.72%) had MACE in 188 participants and 26 (48.15%) of them died. After fully adjusting for potential confounders, compared to eGFR < 90 mL/min/1.73 m(2), eGFR ≥ 90 mL/min/1.73 m(2) had lower incidence of all-cause mortality (HR = 0.43, 95% CI: 0.22–0.85; P = 0.015) and MACE (HR = 0.51, 95% CI: 0.27–0.96; P = 0.038). Additionally, compared to eGFR < 90 mL/min/1.73 m(2), eGFR ≥ 90 mL/min/1.73 m(2) was independently associated with decreased risk of all-cause mortality (HR = 0.33; 95% CI 0.14–0.76, P = 0.010) and MACE (HR = 0.27; 95% CI 0.11–0.65, P = 0.004) in male, but not in female. CONCLUSION: In conclusion, decreased eGFR is a risk factor for all-cause mortality and MACE in individuals with DFO. Additionally, male with decreased eGFR had a higher risk of all-cause mortality and MACE, but female did not.