Background: The influence of metabolic syndrome (MetS) on kidneys is related to many complications. We aimed to assess the association between MetS and chronic renal disease defined by a poor estimated glomerular filtration rate (eGFR) and/or the presence of microalbuminuria/macroalbuminuria. Methods: 149 patients (77 males/72 females) were enrolled in the study. Chronic renal disease was defined according to KDIGO 2012 criteria based on eGFR category and classified albuminuria. MetS was studied as a dichotomous variable (0 to 5 components) including hypertension, waist circumference, low HDL-cholesterol, high triglycerides, and high glucose. Results: The association between clustering MetS and both classified eGFR and classified albuminuria (x2 = 50.3, p = 0.001 and x2 = 26.9, p = 0.003 respectively) was found to be significant. The MetS presence showed an odds 5.3-fold (1.6–17.8) higher for low eGFR and 3.2-fold (1.2–8.8) higher for albuminuria in combination with the presence of diabetes mellitus, which also increased the risk for albuminuria by 3.5-fold (1.1–11.3). Albuminuria was significantly associated with high triglycerides, hypertension, high glucose (x2 = 11.8, p = 0.003, x2 = 11.4, p = 0.003 and x2 = 9.1, p = 0.01 respectively), and it was mildly associated with a low HDL-C (x2 = 5.7, p = 0.06). A significant association between classified eGFR and both high triglycerides and hypertension (x2 = 9.7, p = 0.04 and x2 = 16.1, p = 0.003 respectively) was found. Conclusion: The clustering of MetS was significantly associated with chronic renal disease defined by both classified eGFR and albuminuria. The definition of impaired renal function by classified albuminuria was associated with more MetS components rather than the evaluation of eGFR category. MetS may contribute to the manifestation of albuminuria in patients with diabetes mellitus.

Background/Aim: Pulse pressure (PP) is a result of arterial stiffness seen in dialysis patients, but may be a consequence of fluid overload. We examined the role of β₂-microglobulin (β₂M) in PP in relation to metabolic alterations in patients on different hemodialysis (HD) modalities. Methods: We studied 76 hemodialyzed patients on regular HD (n = 34), predilution bagged hemodiafiltration (n = 19) and online predilution hemodiafiltration (n = 23). β₂M levels were measured by radioimmunoassay, and the clearance of β₂M was assessed by Kt/V for β₂M. Arterial stiffness was measured as carotid-femoral pulse wave velocity, and PP was derived. Insulin levels were measured using immunoradioassay, and insulin resistance was calculated using homeostasis model assessment insulin resistance (HOMA-IR). Serum bicarbonate levels were measured using a blood gas analyzer, and percent sodium removal was calculated. Results: β₂M levels predict increased PP (p = 0.02) adjusting for age, HD modalities, HD duration, HOMA-IR and percent sodium removal. β₂M was positively associated with HOMA-IR (r = 0.306, p = 0.007). Serum bicarbonate levels and carotid-femoral pulse wave velocity were inversely associated (r = –0.719, p = 0.001). Conclusions: β₂M levels were positively associated with PP, which was influenced mainly by dialysis modality fluid and sodium balance and less by arterial stiffness. β₂M levels were positively associated with insulin resistance. Uremic acidosis may contribute to arterial stiffness.

Background: Metabolic acidosis, a common condition particularly in the end-stage of renal disease patients, results in malnutrition, inflammation and oxidative stress. In this study, we focused on the association between low serum bicarbonate and cardiovascular disease in patients on intermittent dialysis. Methods: We studied 52 on-line-pre-dilution hemodiafiltration (on-l HDF) patients, 32 males and 20 females, with a mean age of 58.01 ± 15.4 years old. Metabolic acidosis was determined by serum bicarbonate concentrations less than 22 mmol/L. Residual renal function (RRF) was defined by interdialytic urine volume. Kaplan–Meier curves and Cox regression models were performed to predict coronary artery disease (CAD), defined by ejection fraction <50%, or diastolic dysfunction congestive heart failure (CHF) and peripheral vascular disease (PVD). Results: Kaplan–Meier analyses showed that a lower or higher than 22 mmol/L serum bicarbonate metabolic acidosis status was significantly associated with both PVD and diastolic dysfunction (log-rank = 5.07, p = 0.02 and log-rank = 5.84, p = 0.01, respectively). A similar prevalence of serum bicarbonate on CAD or CHF by low ejection fraction was not shown. The RRF was associated with PVD event and serum bicarbonate less than 22 mmol/L (log-rank = 5.49, p = 0.01 and log-rank = 3.9, p = 0.04, respectively). Cox regression analysis revealed that serum bicarbonate and RRF were significant risk factors for PVD after adjustment for confounders. Furthermore, RRF adjusted for covariates was shown to be a significant risk factor for diastolic dysfunction. Conclusion: Low serum bicarbonate was associated with peripheral vascular disease and diastolic dysfunction in intermittent dialysis. The residual renal function may impact patients’ outcomes through its relationship with metabolic acidosis status, particularly for peripheral vascular disease manifestation.

Background Intradialytic hypertension was associated with a high mortality risk. We examined the relationship between intradialytic hypertension and metabolic disorders in hemodialysis treatment patients. Methods We studied 76 patients in online hemodiafiltration. Dialysis adequacy was defined by Kt/V for urea. Normalized protein catabolic rate (nPCR), as a marker of protein intake, was calculated. Sodium removal was determined as percent sodium removal. Metabolic acidosis was determined by serum bicarbonate less than 22 mmol/L. Interdialytic urine volume more than 100 ml was recorded. Intradialytic hypertension was defined by an increase in systolic blood pressure equal to 10 mmHg from pre- to posthemodialysis. Arterial stiffness was assessed as carotid-femoral pulse wave velocity (c-fPWV) and carotid augmentation index (AIx). Chi-square tests and logistic regression analysis were applied for intradialytic hypertension prediction. Results Patients with intradialytic hypertension were older and had significantly lower hemoglobin, nPCR, urine output, and serum bicarbonate and significantly higher c-fPWV, though similar Kt/V for urea, than patients without intradialytic hypertension. They also had increased sodium removal and pulse pressure related to less urine output. Serum bicarbonate was inversely associated with c-fPWV (r = −0.377, p = 0.001). Chi-square test showed significant association between intradialytic hypertension and serum bicarbonate < 22 mmol/L (x2 = 5.6, p = 0.01), which was supported by an adjusted model. Conclusion The intradialytic hypertension was significantly associated with metabolic disorders including malnutrition/inflammation and uncontrolled metabolic acidosis in hemodialysis treatment patients. Severe metabolic acidosis may reflect sodium imbalance and hemodynamic instability of these patients resulting in volume overload and increased vascular resistance.

BACKGROUND Metabolic disturbances including changes in serum calcium, magnesium or phosphate (P) influence the prevalence of type 2 diabetes mellitus (DM). We assessed the importance of serum P in elderly patients with type 2 DM vs non-diabetes mellitus (non-DM) in relation to renal function. AIM To determine the association between serum P and serum glucose or insulin resistance in diabetic and non-diabetic patients. METHODS One hundred-ten subjects with a mean age of 69.02 ± 14.3 years were enrolled. Twenty-nine of the participants had type 2 DM (26.4%). The incidence of hypertension, smoking and receiving vitamin D (vitD) derivates were recorded. The participants were classified by both estimated glomerular filtration rate (eGFR) and albuminuria categories according to the Kidney Disease Improving Global Outcomes 2012 criteria. RESULTS We divided the patients in two groups according to the P cut-off point related to DM value. A comparison between high and low P showed that body mass index 30.2 ± 6.3 vs 28.1 ± 4.6 ( P = 0.04), mean glucose 63.6 vs 50.2 ( P = 0.03), uric acid 6.7 ± 1.6 vs 6.09 ± 1.7 ( P = 0.05), mean intact-parathyroid hormone 68.06 vs 47.4 ( P = 0.001), systolic blood pressure 147.4 ± 16.7 vs 140.2 ± 16.1 ( P = 0.02), mean albuminuria 63.2 vs 50.6 ( P = 0.04) and eGFR 45.6 ± 22.1 vs 55.4 ± 21.5 ( P = 0.02) were significantly different. χ 2 tests showed a significant association between high P and DM, hypertension, receiving vitD, smoking and eGFR stage ( χ 2 = 6.3, P = 0.01, χ 2 = 3.9, P = 0.03, χ 2 = 6.9, P = 0.009, χ 2 = 7.04, P = 0.01 and χ 2 = 7.36, P = 0.04, respectively). The adjusted model showed that older age, female gender and increased body mass index were significant predictors of type 2 DM when entering the covariates. CONCLUSION High serum P contributes to vascular and metabolic disturbances in elderly patients with type 2 DM and renal impairment.

BackgroundHyperglycemia appears to play a significant role on the inflammatory cytokines production. Beta2-microglobulin (beta2M) is accumulated in the circulation of dialysis patients. We studied the relationship between glycemic control defined by glucose serum concentrations and insulin resistance, beta2M and markers of inflammation in patients on renal replacement therapies with or/and without diabetes mellitus.MethodsWe enrolled 96 dialyzed patients, 62 males and 34 females. The treatment modalities which were applied were : regular hemodialysis (HD, n = 34), predilution hemodiafiltration (HDF, n = 42) and peritoneal dialysis (PD, n = 20). Dialysis adequacy was defined by Kt/V for urea.Beta2M and insulin serum concentrations were measured by radioimmunoassays. hsCRP and TNF-α serum concentrations were measured by ELISA. Insulin resistance was calculated using the homeostasis model assessment of insulin resistance (HOMA-IR).We examined the association of elevated serum glucose with inflammatory factors and we built a multivariable model to investigate if glucose could be a potential determinant of beta2M serum levels.ResultsSerum glucose was positively correlated with beta2M and TNF-α (r = 0.320, p = 0.002 and r = 0.215, p = 0.03 respectively).We observed significant association between the patients with higher serum glucose concentrations and the patients with greater beta2Μ concentrations (x2 = 4.44, p = 0.03). Multivariable model showed that glucose acts as a significant independent determinant of beta2M adjusting for age, gender, dialysis modality and metabolic acidosis status.ConclusionsThe elevated glucose concentrations were positively associated with both, greater beta2M serum concentrations and up-regulated inflammatory procedure in dialysis patients with or/and without diabetes mellitus.

Background: Residual renal function (RRF) provides several benefits to patients on dialysis. Monocyte chemoattractant protein-1 (MCP-1) plays an important role in atherosclerotic lesions. We considered the relationship between RRF and cardiovascular morbidity and the significant role of MCP-1 serum concentrations in hemodiafiltration (HDF) patients. Methods: We enrolled 76 patients on on-line HDF. RRF was defined by interdialytic urine output, and we studied the patients in two groups according to the preservation or not of urine output. MCP-1 levels were measured using enzyme-linked immunosorbent assay. χ² tests were applied for the association between RRF and left ventricular hypertrophy (LVH), coronary artery disease (CAD), peripheral artery disease (PAD), and systolic and diastolic cardiac dysfunction. We built an adjusted model using logistic regression analysis for the factors which might impact on the loss of urine output. Results: χ² tests showed a significant association between the loss of urine output and LVH, diastolic dysfunction, and PAD (χ² = 7.4, p = 0.007; χ² = 14.3, p = 0.001; χ² = 4.2, p = 0.03, respectively), although the association with CAD and systolic dysfunction was found to be nonsignificant. The patients without RRF had significantly higher MCP-1, and the urine volume was inversely associated with MCP-1 (r = -465, p = 0.03). In the built adjusted model, the elevated MCP-1 was found to be a significant predictor for the loss of RRF. Conclusion: The loss of RRF was significantly associated with LVH, diastolic dysfunction, and PAD in HDF patients. The increased MCP-1, affected by the lack of urine, may act as an additional underlying factor on this relationship, reflecting a progressive inflammation/oxidative stress condition.

Background and Objectives: Uncorrected metabolic acidosis leads to higher death risk in dialysis patients. We observed the relationship between metabolic acidosis status and mortality rate in patients on renal replacement therapy during a median follow up time of 60 months. Methods: We studied 76 patients on an on-line hemodiafiltration. The dialysis adequacy was defined by Kt/V for urea. The Framingham risk score (FRS) points were used to determine the 10-year risk for coronary heart disease. We examined the impact of high or low serum bicarbonate concentrations on mortality rate and on 10-year risk for coronary heart disease via the Kaplan-Meier method. Cox's model was used to evaluate a combination of prognostic variables, such as dialysis adequacy defined by Kt/V for urea, age and serum bicarbonate concentrations. Results: We divided the enrolled patients in three groups according to serum bicarbonate concentrations (< 20 mmol/L, 20-22 mmol/L and > 22 mmol/L). Kaplan-Meier survival curve for the impact of serum bicarbonate concentrations on overall mortality was found significant (log-rank = 7.8, P = 0.02). The prevalence of serum bicarbonate less or more than 20 mmol/L on high FRS (> 20%) by Kaplan-Meier curve was also found significant (log-rank = 4.9, P = 0.02). Cox's model revealed the significant predictive effect of serum bicarbonate on overall mortality (P = 0.006, OR = 1.5, 95% CI = 1.12-1.98) in combination to Kt/V for urea and age. Conclusion: Uncorrected severe metabolic acidosis, defined by serum bicarbonate concentrations less than 20 mmol/L, is associated with a 10-year risk for coronary heart disease more than 20% and high overall mortality in patients on renal replacement therapy.