Early diagnosis of mineral and bone disorders in patients with diabetic kidney disease on the background of type 2 diabetes
Authors: Yerokhovych V.M. , Karpenko O.V. , Paliienko I.A. , Kobyliak N.M. , Bobryk M.I. , Shuliarenko L.V. , Rudenko O.A. , Kyriienko D.V. , Bolanowski M. , Komisarenko Y.I. 
Published: August 2024

Background. Today, diabetes mellitus is an actual problem, characterized by a progressive increase in the number of patients with a high frequency of complications that require early diagnosis and timely treatment. Diabetic nephropathy is among the most common microvascular lesions. Patients may have clinical manifestations of diabetic kidney disease that go beyond the classic symptoms and have extrarenal consequences in the form of bone mineral disorders. The purpose of the work is to carry out a comprehensive assessment of early markers of kidney damage and changes in bone disorder indicators in patients with type 2 diabetes and to identify correlations between the studied parameters. Materials and methods. Eighty patients with type 2 diabetes participated in the study. They were divided according to the glomerular filtration rate: GFR < 60 ml/min/m2 (1st group, n = 26), GFR ≥ 60 ml/min/m2 (2nd group, n = 54). Results. Analysis of early markers of kidney damage revealed some significant differences between the groups. Indicators of daily urine albumin-creatinine ratio, serum cystatin C, parathyroid hormone, uric acid, and vitamin D-binding protein were significantly higher in patients with GFR < 60 ml/min/m2. The average level of vitamin D (25OH) in both groups corresponded to a deficient state, and the 1st group was marked by a statistically significantly lower level compared to the 2nd group: 12.32 ± 4.84 and 16.72 ± 5.82 ng/ml, respectively (p = 0.001). In the 1st group, vitamin D deficiency was observed in 92.3 % of cases, and in the 2nd group, in 74.1 % (p = 0.56). According to the correlation analysis, some reliab­le relationships were found: in the 1st group, there was a negative correlation between GFR and parathyroid hormone (r = –0.816, p < 0.001). An inverse correlation was revealed between GFR and cystatin C in the 1st (r = –0.862, p < 0.001) and 2nd groups (r = –0.322, p = 0.18). Among all examined participants, there was a linear negative correlation between GFR and uric acid (r = –0.452, p < 0.001). Vitamin D (25OH) didn’t have a significant relationship with GFR, however, we found a negative correlation with the daily urine albumin-creatinine ratio (r = –0.253, р = 0.024) and cystatin C (r = –0.303, p = 0.006), which confirms the role of cholecalciferol in mineral bone disorders in patients with chronic kidney disease. In our study, an inverse correlation was found between GFR and vitamin D-binding protein in the 1st (r = –0.436, p = 0.26) and 2nd group (r = –0.283, p = 0.038), which probably indicates a possible compensatory response of transport protein to initial mineral bone disorders in patients with diabetic kidney disease. Conclusions. Early detection of bone mineral disorders in diabetic kidney disease is important to increase the efficiency of managing patients with type 2 diabetes and timely treatment, prevention of cardiovascular complications and bone metabolism disorders