Proaterogenic disorders of lipid and carbohydrate metabolism in chronic kidney disease nondiabetic origin

Abstract

Purpose. Identify the features of lipid and carbohydrate metabolism, state of lipid peroxidation (LPO) in patients with chronic kidney disease (CKD) nondiabetic origin depending on the degree of renal dysfunction.

Materials and methods. The study involved 62 patients with nondiabetic CKD (43 men and 22 women, mean age 59,09±1,46 years). Depending on the functional capacity of the kidneys the patients were divided into 3 subgroups: 1^st - 27 individuals with GFR ≥60 ml/min, 2^nd - 18 patients with GFR 59-30 ml/min, 3^rd - 17 patients with GFR <30 ml/min. Control group - 20 healthy individuals. Were determined: the levels of total cholesterol (TC), low density lipoprotein cholesterol (LDL-cholesterol), high density lipoprotein cholesterol (HDL-cholesterol), very low density lipoprotein cholesterol (VLDL-cholesterol), triglycerides (TG), malondialdehyde (MDA), the activity of ceruloplasmin (CP), glucose and glycosylated hemoglobin (HbA1s).

Results. In 95,2% patients of the total group had significantly higher than the target level of TC (mean value - 4,12±0,12 mmol/l). The average level of TC (mmol/l) increased with decreasing of GFR, significantly exceeding the value of the control group (p<0,001): 5,45±0,26 (1^st), 5,91±0,43 (2^nd), 6,37±0,56 (3^rd). Increasing of the levels of LDL-cholesterol, above target values, was recorded in all (100%) patients. In the total group, its value was 3,65±0,18 mmol/l, which is in 1.5 times higher than the level of control (p<0,001). LDL-cholesterol level (mmol/l) increased with the progression of renal dysfunction: from 3,32±0,21 (1^st) and 3,77±0,34 (2^nd) to 4,12±0,44 (3^rd), which was significantly higher than in controls (p<0,001). The average level of TG was elevated in 64,5% of patients. The levels of TG (mmol/l) were: 1,95±0,12 (1^st), 2,02±0,19 (2^nd) (p<0,001, compared to the control), 2,32±0,28 (3^rd) – in 1,2 (p<0,05) and in 2,7 times (p<0,001) higher than in the 1^st subgroup and control, respectively.

Increased levels of HbA1c ≥7% were recorded in 41,9% persons of the total group, and were significantly higher in the 2^nd (50%) and 3^rd subgroups (58,8%), compared with 1^st (25,9%) subgroup. Average levels of HbA1c were significantly higher in subgroups than the value in the control group (p<0,001). In the 1^st subgroup the level of HbA1c was 6,53±0,20%, in the 2^nd - increased to 7,25±0,41% (p<0,05), in the 3^rd reached 7,48±0,36%, that was in 1,2 times higher than the level of the 1^st subgroup (p<0,01). Elevated levels of HbA1c were recorded in patients with CKD in the background of normal glucose values (in the absence of diabetes and impaired glucose tolerance).

Elevated levels of MDA were found in 91,9% of patients and CP – in 45,2% of people. Their mean values were significantly higher in patients with CKD compared with the control group. Activity of LP increased with decreasing of GFR. Elevated levels of MDA were found in 85,2% patients of the 1^st subgroup, in 94,4% - of the 2^nd subgroup, and up to 100% - of the 3^rd subgroup. Prevalence and mean values of MDA increased with decreasing of renal function (0,49±0,02 nmol/mg (I), 0,54±0,03 nmol/mg (II), 0,63±0,02 nmol/mg ( III)), significantly exceeding its value in the control group.

Conclusion. Patients with CKD nondiabetic origin had a significant increasing of atherogenic lipid fractions (TC, LDL-cholesterol, TG) and increased levels of HbA1c on the background of normal glucose values. Detected changes are more pronounced in patients with the lowest GFR (<30 ml/min). Also, the worst condition of LP was found in patients with severe renal dysfunction, which indicated the significant activation of prooxidant processes. The combination of this disorders may significantly increase the risk of cardiovascular complications in patients with CKD of nondiabetic origin.

Key words: chronic kidney disease, lipid metabolism, carbohydrate metabolism, lipid peroxidation, glicated glomerular filtration rate.