Abstract
To evaluate the association between presenting estimated glomerular filtration rate (eGFR) and clinical outcomes in patients hospitalized with diabetic foot infections. This retrospective cohort study included 344 patients with moderate to severe diabetic foot infections. Patients were categorized into three groups based on presenting estimated eGFR: eGFR ≥60 (eGFR >60 mL/min), eGFR 30-60 (eGFR 30-60 mL/min) and eGFR <30 (eGFR <30 mL/min). Outcomes assessed included wound healing, time to heal, re-infection, amputation, mortality and re-hospitalization for infection. Compared with patients with eGFR <30, patients with eGFR ≥60 had significantly lower rates of retinopathy, peripheral arterial disease and use of beta blockers or calcium channel blockers. Glycated haemoglobin levels were inversely related to eGFR, decreasing as eGFR severity increased. Haemoglobin levels were significantly lower, and inflammatory markers (ESR and CRP) were significantly higher in patients with eGFR <30. There were no significant differences among eGFR groups in rates of wound healing, time to heal, re-infection or amputation. However, mortality increased with decreasing eGFR (1.9% in eGFR ≥60 vs. 3.2% in eGFR 30-60 vs. 8.1% in eGFR <30; p = 0.04). Similarly, re-hospitalization for infection at a different site also increased with decreasing eGFR (20.5% in eGFR ≥60 vs. 28.1% in eGFR 30-60 vs. 48.4% in eGFR <30; p < 0.01). In diabetic foot infections, presenting eGFR severity did not affect rates of wound healing, time to heal, re-infection or amputation. However, decreasing eGFR was associated with increased mortality and re-hospitalization for infection at a different site. In this study, presenting eGFR was not a predictive value for wound healing or time until healing, however was associated with rehospitalization and overall mortality this diabetic foot population.