Albuminuric diabetic kidney disease predicts foot ulcers in type 2 diabetes

Diabetic Foot Ulcers (DFU) are feared among individuals with diabetic kidney disease (DKD), but it is unclear whether they are more frequent, especially in normoalbuminuric DKD. Five hundred and twenty patients admitted in our diabetology ward from 2007 to 2017 were followed up during 54 ± 26 months. New DFUs were registered, and their relationship with the initial renal status was analyzed by LogRank and multivariate Cox regression analysis. The 520 subjects were mainly men (57.9 %), 62 ± 9 years old, with a duration of diabetes of 14 ± 10 years, HbA1c: 8.7 ± 1.8 % (72 ± 19 mmol/mol), and complications: 33.7 % macroangiopathies, 22.1 % previous foot ulcers, 44.8 % DKD, 26.9 % retinopathies. Fifty-seven new DFU occurred, mainly in subjects with DKD. DKD was related to later DFU (HR: 1.79; 95%CI: 1.05-3.07), this relationship stayed significant adjusted for age, gender, and a history of previous DFU (HR: 3.61; 95%CI: 2.11-6.18), and further adjusted for the duration of diabetes, HbA1c, BMI, arterial hypertension, and dyslipidemia. Among the 233 subjects with DKD, 129 (55.3 %) had an isolated AER > 30 mg/24H, 41 (17.6 %) had an isolated eGFR<60 mL/min/1.73 m2, and 63 (27.0 %) cumulated both abnormalities. By Cox regression analysis adjusted for age and gender, albuminuric DKDs were related to later DFU: with eGFR≥60: HR: 1.91; 95%CI: 1.02-3.59, with eGFR<60: HR: 2.53; 95%CI: 1.25-5.10, whereas normoalbuminuric DKD was not: HR: 1.04; 95%CI: 0.35-3.07, despite similar rates of neuropathies, peripheral arterial diseases, and retinopathies. In people with type 2 diabetes, albuminuric DKD was associated with two to three folds increased risk of DFUs, whereas normoalbuminuric DKD was not.