Increased risk of renal events in people with diabetic foot disease: A longitudinal observational study.

Objective: Diabetic kidney disease favors diabetic foot ulcers, however we do not know whether the reverse relation exists. We investigated whether diabetic foot disease (DFD) related to an increased risk of developing renal events.

Research Design And Methods: We conducted a retrospective analysis of a cohort of patients hospitalized for type 2 diabetes mellitus (T2DM) between 2009 and 2017, stratified for the risk of diabetic foot ulcer grades 0 (no risk), 1 and 2 (at risk), and 3 (DFD) according to the International Work Group on Diabetic Foot (IWGDF) classification. We highlighted new renal events (end-stage renal disease or a doubling of serum creatinine) in their medical records until December 2020. The relationship between DFD and later renal events was analyzed by multivariable Cox regression model.

Results: Among 519 patients, 142 (27 %) had a DFD at baseline, and 159 (30 %) were classified as Grades 1 or 2. Thirty-six renal events occurred during the 54 ± 27 months of follow-up: 19 subjects started dialysis, 1 had a renal transplantation, and 16 had a doubling of serum creatinine: 15 each in subjects with DFD and subjects at risk, versus 6 in subjects with Grade 0 DFD (logrank: P = 0.001). Adjusted for i) age and sex; ii) hyperglycemic exposure; iii) conventional cardiovascular risk factors; iv) renal parameters: and v) new diabetic foot ulcers during follow-up, DFD (HR 2.7 to 5.9) and being at risk of DFD Grades 1-2 (HR 2.8 to 5.1) were significantly related to new renal events.

Conclusion: The risk of renal events was increased in people with T2DM and DFD.