The Aim: to define the phenotypes of non-albuminuric and albuminuric chronic kidney disease (NA-CKD and A-CKD) in subjects with type 2 diabetes (T2D).
Methods: One hundred and eighty four T2D patients were included in the study. Patients with urinary albumin to creatinine ratio (UACR) <3 mg/mmol and estimated glomerular filtration rate (eGFR) <60 ml/min×1.73 m2 were classified as NA-CKD group (n=111). Individuals with persistent UACR >3 mg/mmol and eGFR <60 ml/min×1.73 m2 were considered as A-CKD patients (n=73). Urinary nephrin and podocin, as podocyte injury markers, and whey acidic protein four-disulfide core domain protein 2 (WFDC-2), which is considered as a marker of tubulointerstitial involvement, were assessed by ELISA and compared to control (20 nondiabetic subjects).
Results: The NA-CKD pattern was associated with female sex (p=0.04), reduced HbA1c levels (p=0.04) and diuretic use (p=0.001). Patients with A-CKD, as compared to NA-CKD one, demonstrated lower body weight (p=0.02), waist-to-hip ratio (p=0.009), HDL-cholesterol (p=0.01), and lymphocyte count (p=0.002). Age, diabetes duration, the prevalence of diabetic retinopathy, coronary artery disease, myocardial infarction, chronic heart failure and stroke did not differ between the groups. The nephrin and podocin concentrations, adjusted to urinary creatinine, were increased significantly in subjects with A-CKD only (p=0.002 and 0.04 respectively). The excretion of WFDC-2 was elevated in both NA-CKD and A-CKD groups (p=0.01 and p=0.0003 respectively).
Conclusion: In T2D subjects, female gender, acceptable glycemic control and treatment with diuretics are associated with NA-CKD, whereas abdominal obesity, poor glycemic control, and elevated urinary excretion of podocyte markers are the features of A-CKD. Urinary WFDC-2 excretion is increased in both CKD phenotypes.
A.I. Korbut: None. V. Klimontov: Advisory Panel; Self; Sanofi. Speaker's Bureau; Self; AstraZeneca, Boehringer Ingelheim International GmbH, Sanofi.