Zeynep Bal

Long-Term Oral Nutrition Supplementation Improves Outcomes in Malnourished Patients With Chronic Kidney Disease on Hemodialysis

Background: There is no consensus on the type, time of initiation, or duration of use of enteral nutrition in patients with chronic kidney disease (CKD). This study aimed to compare the effects of a renal-specific oral nutrition supplement (RS-ONS) and a standard recommended nutrition regime on biochemical and nutrition markers in malnourished patients with CKD on hemodialysis. Methods: Sixty-two malnourished patients with CKD, divided into experimental (RS-ONS; n = 32; mean [SD] age, 62.0 [11.3] years; 55.2% female) and control (CON; n = 30; mean [SD] age, 57.2 [12.3] years; 31% female) groups, were evaluated for anthropometric, biochemical, and inflammatory parameters. Results: Mean (SD) serum albumin levels were significantly increased in the RS-ONS group from 3.5 (0.3) g/dL at baseline to 3.7 (0.2) g/dL at 6 months (P = .028). Significantly fewer patients had serum albumin levels of <3.5 g/dL after month 6. Dry weight of patients significantly increased in the RS-ONS but decreased in the CON groups (P < .001 for each). Percent change from baseline revealed negative results for bioelectrical impedance analysis (P < .001) in the CON group. Malnutrition inflammation score at 6 months (P = .006) and erythropoietin (EPO) dose requirements were higher in the CON group (P = .012). Conclusions: Our findings indicate that consuming RS-ONS improves serum albumin and anthropometric measures, as well as reduces EPO dose, in patients with CKD.

Body Composition Analysis of Patients on Waiting List for Cadaveric Renal Transplantation: A Comparison of Hemodialysis and Peritoneal Dialysis Patients

BACKGROUND Bioelectrical impedance analysis is a simple, noninvasive method of assessing body composition. Dialysis modality and selection of buffer type may have an impact on body composition. The aim of our study was to compare body compositions of patients from the waiting list for cadaveric renal transplantation according to the dialysis modality. METHODS We examined a total of 152 (110 hemodialysis [HD] and 42 continuous ambulatory peritoneal dialysis [CAPD]) patients. Demographic data were collected from patient charts. The last 6 months routine laboratory evaluations including hemoglobin, serum creatinine, intact parathyroid hormone, albumin, C reactive protein, calcium, phosphorus were collected. Body compositions were measured using the Tanita BC-420MA Body Composition Analyzer (Tanita, Tokyo, Japan). We made a subanalysis of the CAPD group according to buffer choices as follows: lactate-buffered (n = 16) and bicarbonate/lactate-buffered (n = 26) solution users. RESULTS The body weight (P = .022), body mass index (BMI; 25.8 ± 4.7 vs 23.4 ± 4.9 kg/m(2), P = .009), muscle mass (P = .01), fat-free mass (P = .013), and visceral fat ratio (9.5 ± 5.4 vs 7.3 ± 4.1 %, P = .022) were significantly higher in the CAPD group. Total body water of CAPD patients were also higher (P = .003), but total body water ratios of HD and CAPD groups were similar. Fat and fat-free mass ratios of patient groups were also similar. Comparing CAPD subgroups we observed that patients using bicarbonate/lactate-buffered solutions had higher body weights (P = .038), BMI (27.1 ± 5 vs 23.7 ± 3.5 kg/m(2), P = .018) values, and visceral fat ratios (8.0 ± 5.2 vs 4.6 ± 2.5 %, P = .023). These patients also tend to have higher fat mass without statistical significance (P = .074). Fat, muscle, and fat-free mass total body water ratios of peritoneal dialysis subgroups were similar. CONCLUSION We believe that body composition analysis should be used as a complementary method for assessing nutritional status of PD and CAPD patients as body weight or BMI measurements do not reflect fat, muscle masses, and visceral fat ratios in these patients. Stable, well nourished CAPD patients should be closely observed and be encouraged to increase daily exercise and/or decrease calorie intake from other sources to decrease risks associated with abdominal obesity.

Reliability of bioelectrical impedance analysis in the evaluation of the nutritional status of hemodialysis patients - a comparison with Mini Nutritional Assessment.

INTRODUCTION Protein-energy wasting (PEW) is a strong predictive factor for morbidity and mortality in patients who have end-stage renal disease (ESRD). Mini Nutritional Assessment (MNA) is an important and confirmed tool to evaluate PEW that has been recommended by many guidelines. Bioelectrical impedance analysis (BIA) is a noninvasive technique for assessing body composition. The aim of the present study was to analyze the reliability of BIA in malnutrition diagnosis by comparing it with standard MNA in a group of 100 ESRD patients. METHODS One hundred ESRD patients who were medically stable and under dialysis treatment for at least 6 months were enrolled to the study. Monthly assessed serum creatinine, albumin, C-reactive protein (CRP), and lipid profiles from the last 6 months prior to the study were retrospectively collected. A standard Full-MNA and body composition analyses were applied to all patients. Body compositions were analyzed with the BIA technique using the Body Composition Analyzer (Tanita BC-420 MA; Tanita, Tokyo, Japan). Patients were classified into three groups according to MNA scores as PEW (n = 15, score <17), moderate PEW or risk group (n = 49, score 17-23.5), and well-nourished (n = 36, score ≥ 24) patients. RESULTS Mean duration of maintenance hemodialysis treatment was significantly shorter in the PEW group compared to both of the other groups described (P = .015). Well-nourished and risk groups had lower CRP and higher albumin levels compared to PEW patients; however, these values were statistically similar in these two groups (P = .018, .01, respectively). According to BIA findings, well-nourished patients had the highest fat ratio, fat mass, muscle mass, visceral fat mass, and fat-free mass compared to both moderate the PEW/risk and the PEW groups (P < .05). Risk group patients also had higher muscle mass, visceral fat mass, and fat-free mass values compared to the PEW group (P < .05). A correlation analysis revealed that MNA scores were positively correlated with albumin (P = .005), creatinine (P = .049), fat mass (P = .045), muscle mass (P = .001), visceral fat ratio (P = .007), and BMI (P = .047) and in negative correlation with CRP (r = -0.357, P = .0001) levels. CONCLUSIONS We recommend BIA as a complementary diagnostic tool to evaluate nutritional status of ESRD along with MNA, anthropometric measures, and classical biochemical markers.

Differential influence of vitamin D analogs on left ventricular mass index in maintenance hemodialysis patients.

Purpose Secondary hyperparathyroidism (SHPT) is a common feature in maintenance hemodialysis (MHD) patients. Inadequate treatment of SHPT has been associated with cardiovascular complications, and vitamin D therapy might influence the development of cardiovascular diseases. In the present study, we aimed to evaluate the effects of intravenous paricalcitol and calcitriol treatments on left ventricular mass index changes in MHD patients. Methods We conducted an observational study with a 12-month follow-up duration to compare the outcomes of intravenous paricalcitol and calcitriol treatments in MHD patients. Eighty patients with moderate to severe SHPT were enrolled in the study. All the patients had normalized total serum Ca concentration <10.5 mg/dL, serum calcium-phosphorus product (Ca × P) <75, and parathyroid hormone level (PTH) level ≥300 pg/mL at the begining of the follow-up period. Results The patients were divided into a paricalcitol group (n = 40) and a calcitriol group (n = 40). The demographic, clinical, and biochemical characteristics of the patients were similar at baseline. We observed significantly superior control of SHPT; lesser frequency of hypercalcemia and hyperphosphatemia, and Ca × P level elevations; and interruption of vitamin D treatment in the paricalcitol group. Moreover, we found no significant change in left ventricular mass index in the paricalcitol group, but found a significantly increased left ventricular mass index in the calcitriol group during the follow-up period (from 136.6 ± 35.2 g/m2 to 132.9 ± 40.4 g/m2 vs. from 137.2 ± 30.1 g/m2 to 149.4 ± 31.0 g/m2; p<0.044). Conclusion We observed that, compared with calcitriol therapy, paricalcitol therapy reduced the PTH concentrations more effectively without causing hypercalcemia and hyperphosphatemia and might have a substantial beneficial effect on the development of left ventricular hypertrophy.

Evaluation of Nutritional Status in Renal Transplant Recipients in Accordance with Changes in Graft Function

INTRODUCTION AND AIMS Renal transplantation (RT) is the ultimate treatment modality for end-stage renal disease (ESRD) patients. Malnutrition is a strong predictor of cardiovascular disease among ESRD patients. Body composition analysis using bioimpedance devices (BIA) is a useful noninvasive tool to detect malnutrition in this population. We investigated the impact of graft function on nutritional status and reliability of BIA to detect malnutrition in RT recipients. METHODS We evaluated retrospectively 189 RT recipients including 59 females, and of overall mean age of 38.3 ± 10.6 years who had a minimum posttransplant follow-up of 12 months. Body Composition Analyzer (Tanita BC-420MA) determinations were complemented with monthly assessments of biochemical parameters. Patients were divided into 3 groups according to glomerular filtration rate (GFR) levels: normal graft function/high GFR group (group 1, normal creatinine levels, no proteinuria and GFR ≥ 90 mL/min; n = 59); low renal function/low GFR group (normal or high creatinine levels with low GFR levels; group 2; GFR 89-60 mL/min; n = 87) and group 3, (GFR < 60 mL/min; n = 43). RESULTS Group 3 patients displayed significantly lower as well as hemoglobin albumin and calcium concentrations, with higher phosphorus and parathyroid hormone levels (P = .0001). They also showed significantly lower body weight (P = .0001), body mass index (P = .002), fat (P = .002) and muscle (P = .0001) contents as well as fat-free mass (P = .0001). Group 2 patients had significantly lower values compared with group 1 and higher values than group 3. GFR values positively correlated with albumin, fat, muscle, and fat-free mass (r = 0.337, 0.299, 0.281, 0.278, respectively; P = .0001). GFR values positively correlated with visceral fat ratio (r = 0.170; P = 0.02), body mass index (r = 0.253; P = .0001), and waist-hip ratio (r = 0.218; P = .006). CONCLUSION Loss of muscle and fat mass is an early sign of malnutrition among RT recipients. It is closely associated with loss of GFR. BIA is a noninvasive and reliable diagnostic tool that should be included in the follow-up of these patients for an early diagnosis of malnutrition-related complications.

Left Ventricular Mass Index and Its Relationship to Ambulatory Blood Pressure and Renal Resistivity Index in Renal Transplant Recipients

INTRODUCTION AND AIMS Left ventricular hypertrophy (LVH) is frequently observed in patients with end-stage renal disease and renal allograft recipients. It is an independent, strong predictor of morbidity and mortality. Renal resistive index (RRI) is an important determinant of graft function in transplant recipients. In essential hypertension, increased RRI is associated with reduced renal function and tubulointerstitial damage. In this present study, we investigated the association of ambulatory blood pressure monitoring parameters and RRI on left ventricular mass index among renal transplant recipients. METHODS Charts of 98 renal transplant recipients with echocardiography, ambulatory blood pressure monitoring, and renal Doppler ultrasonography as well as laboratory tests including serum creatinine, glomerular filtration rate, and C-reactive protein (CRP) level at the end of post-transplantation year 1 were analyzed in this study. LVMI was calculated using the Devereux formula with echocardiographic findings. RESULTS Left ventricular mass index (LVMI) positively correlated with mean systolic blood pressure (SBP) (r = 0.512; P = .0001), mean nighttime SBP (r = 0.312; P = .007), mean nighttime diastolic blood pressure (DBP) (r = 0.427; P = .005), renal resistive index (RRI; r = 0.290; P = .004), and age (r = 0.371; P = .001). Multiple logistic regression analysis revealed that mean and maximum nighttime SBP and RRI were independent risk factors for LVMI (P = .001, .035, and .05, respectively). CONCLUSION High RRI is one of the main indicators of cardiovascular disease in renal transplant recipients. Additionally, older age, high blood pressure, and nondipper pattern are important risk factors of LVH.

Low Graft Function and Ongoing Hyperparathyroidism Are Closely Related to Post-Transplantation Osteoporosis

INTRODUCTION Renal transplantation (RT) is the gold standard therapy for chronic renal failure. Immunosuppressive drug choice, malnutrition, adynamic bone disease and hyperparathyroidism are important factors impacting the development of posttransplant osteoporosis. Body composition analysis with bioimpedance devices (BIA) is a useful noninvasive tool to detect malnutrition among the RT population. We investigated the effects of graft function, immunosuppressive drug regimens and biochemical characteristics on bone mineral density of RT patients as well as the reliability of BIA measurements to diagnose osteoporosis. METHODS One hundred three recipients with a minimum of 12 months post-RT follow-up underwent body composition analysis using the Tanita Analyzer. The last 6 months of monthly biochemical parameters and glomerular filtration rates (GFR) as well as drug regimens were collected retrospectively from patient charts. Patients were divided into 2 groups, according to their femoral neck and lumbal T scores, as osteoporosis (n = 42) and control groups (n = 61). RESULTS The mean GFR of osteoporotic patients was significantly lower (P = .04) and parathyroid hormone (PTH) levels significantly higher (P = .002). According to BIA, osteoporotic patients showed lower bone mass, fat mass, visceral fat ratio, muscle mass, waist-hip ratios, and body mass index values (P < .05). Correlation analysis revealed GFR to negatively correlate with PTH (r = -0.231, P = .010) and positively with femur t scores (r = 0.389, P = .0001) as well as with BIA findings (P = .0001). In contrast, PTH levels in negatively correlated with lumbar and femoral neck t scores (r = -0.22, -0.4 and P = .026, .0001, respectively) but not with BIA findings including bone mass. CONCLUSION Changes in bone density after RT were affected by graft function. The rapid loss of bone mineral density emphasizes the need for prevention started in the early posttransplant period. BMD measurements provided a guide for treatment and for subsequent evaluation.

High-Grade Proteinuria as a Cardiovascular Risk Factor in Renal Transplant Recipients

BACKGROUND Proteinuria is a marker of graft damage and is closely associated with a higher risk of morbidity, mortality, and cardiovascular disease in kidney transplant recipients (KTRs). Arterial stiffness is a well-known predictor of vascular calcification and systemic arteriosclerosis. In our study, we aimed to investigate the association between proteinuria and graft/patient survival and to determine whether proteinuria may be a predictor for cardiovascular disease in our KTR population. METHODS Ninety KTRs (31 women; age, 38.7 ± 11 years, with 45.9 ± 9.6 months post-transplantation period) with normal graft functions in the 3 to 5 years of the post-transplantation period were enrolled. All patients were evaluated for their standard clinical (age, sex, and duration of hemodialysis) parameters. High-grade proteinuria was defined as proteinuria >500 mg/day in the 24-hour urine collection. All patients were evaluated by means of pulse-wave velocity (PWV) measurement at the initiation of the study. RESULTS Patients were divided into 2 groups: group 1 (high-grade proteinuria) patients with ≥500 mg/24 hours (n = 30) and group 2 (low-grade proteinuria) patients with <500 mg/24 hours (n = 60). High-grade proteinuria was correlated with higher PWV measurements and lower estimated glomerular filtration levels. Proteinuria appears to precede the elevation of serum creatinine and thus may be a useful marker of renal injury and may also be a contributing factor on deterioration of the graft. CONCLUSIONS High-grade (>500 mg/day) proteinuria in KTRs is strongly associated with poor graft survival and increased risk of cardiovascular events. In our study, we proved the significant difference between high-grade and low-grade proteinuric patients, and we suggest 500 mg/day as the threshold of proteinuria in KTR population.

Post-transplant Hyperuricemıa as a Cardıovascular Risk Factor.

PURPOSE Uric acid is known to impair endothelial cell function and to stimulate the development of renal interstitial fibrosis. The aim of this study was to evaluate the association between first-year hyperuricemia with graft dysfunction and the development of cardiovascular risk disorders in renal transplant recipients. METHODS One hundred kidney transplant recipients (31 female, 45.9 ± 9.6 post-transplantation months) with normal graft functions were enrolled. The clinical biochemical parameters in the first post-transplantation year were retrospectively recorded and searched for the predictive value in yearly determined graft function and association with cross-sectionally analyzed cardiovascular parameters, including body composition analyses, ambulatory blood pressure monitoring data, and pulse wave velocity. Hyperuricemia was defined as an uric acid level of ≥ 6.5 mg/dL that persisted for at least 2 consecutive tests. RESULTS One year after transplantation, 37% of subjects had hyperuricemia. According to cross-sectional data, sagittal abdominal diameter (P = .002) and hip circumferences (P = .013) were significantly higher in hyperuricemic patients than in normouricemic ones. Hyperuricemic patients had higher fat (P = .014) and muscle mass (P = .016) than normouremic patients. Hyperuricemic patients had significantly higher mean systolic BP (P = .044) than normouremic patients. Hyperuricemic patients had significantly higher pulse wave velocity levels (P = .0001) and left ventricular mass index (P = .044) than normouremic patients. The yearly decline in estimated glomerular filtration rate levels was significantly higher in hyperuricemic patients (P = .0001) than in normouricemic ones. CONCLUSION Post-transplantation hyperuricemia is associated with hypertension, arterial stiffness, and dyslipidemia; it should be accepted not only as a marker for renal allograft dysfunction but also as a cardiovascular risk factor in renal transplant recipients.

Pulmonary Hypertension Is Closely Related to Arterial Stiffness in Renal Transplant Patients

INTRODUCTION AND AIMS Pulmonary hypertension (PH) is an independent predictor of increased mortality in patients on dialysis and those undergoing renal transplantation. We investigated PH and its association with vascular calcification and endothelial dysfunction in renal transplant patients. METHODS The records of 300 consecutive patients who underwent renal transplant in our center between 2005 to 2012 were evaluated. PH was defined as systolic pulmonary artery pressure (sPAP) ≥ 35 mm Hg. Demographic information, clinical characteristics, pulse wave velocity (PWv), and renal recessive indices (RRI) were collected and compared among patients with and without PH. RESULTS Eight patients in PH group (age 36 [19] years) and 87 subjects in nPH group (age 35 [9] years) were evaluated. Demographic and clinical characteristics and laboratory data of the 2 groups were similar. Additionally, sPAP was positively correlated with PWv (r = 0.263, P = .01). In multivariate analyses, RRI (P = .004), serum CRP (P = .025), and PWv (P = .001) were associated with pulmonary artery pressure. CONCLUSION PH is significantly associated with arterial stiffness in renal transplant recipients who have a high risk for cardiovascular disease. Considering the common prevalence of cardiovascular diseases, including PH, we suggested that all patients with renal transplantation should be evaluated for regular echocardiographic examination in clinical practice.