Uremic malnutrition is a predictor of death independent of inflammatory status

Analysis of serum phosphate control and phosphate binder utilization in incident hemodialysis patients

The purpose of this study was to conduct a retrospective analysis of serum phosphate level variability in patients new to hemodialysis (HD) and to identify patient characteristics associated with this variability. The medical records of 47,742 incident HD patients attending US outpatient dialysis centers between January 1, 2006 and March 31, 2009 were analyzed. Monthly mean serum phosphate levels determined over a 6-month evaluation period (months 4–9 after HD initiation) were assigned to one of three strata: low (<1.13 mmol/L [<3.5 mg/dL]); target (1.13–1.78 mmol/L [3.5–5.5 mg/dL]); or high (>1.78 mmol/L [>5.5 mg/dL]). Patients were classified into one of six serum phosphate variability groups based on variability among monthly mean phosphate levels over the 6-month evaluation period: consistently target; consistently high; high-to-target; high-to-low; target-to-low; or consistently low. Only 15% of patients (consistently target group) maintained monthly mean serum phosphate levels within the target range throughout the 6-month evaluation period. Age, Charlson comorbidity index, serum phosphate, and intact parathyroid hormone levels prior to HD initiation were strongly associated (P<0.001) with serum phosphate levels after HD initiation. Overall patient-reported phosphate binder usage increased from 35% at baseline to 52% at end of study. The low proportion of patients achieving target phosphate levels and low rates of phosphate binder usage observed during the study suggest that alternative strategies could be developed to control serum phosphate levels. Possible strategies that might be incorporated to help improve the management of hyperphosphatemia in incident HD patients include dietary modification, dialysis optimization, and earlier and sustained use of phosphate binders.

Target weight gain during the first year of hemodialysis therapy is associated with patient survival

BACKGROUND

Hemodialysis (HD) patients are exposed to a high risk of death. Nutritional status has been recognized as a key factor for patient survival. Nutritional markers have been shown to improve after HD onset. In this study we have analyzed the dynamics of target weight (TGW) change and the evolution of other nutritional parameters during the first year of HD treatment and their influence on patients' outcomes.

METHODS

We have analyzed a retrospective cohort of incident patients starting HD therapy between January 2000 and January 2009, and studied the values and changes in TGW, interdialytic weight gain (IDWG), predialysis systolic blood pressure, serum albumin, protein intake, C-reactive protein (CRP) from the start and first week (W1), W8, W12, W26 and W52 in patients who survived the first year of therapy. We have analyzed the relationship between TGW changes with other nutritional parameters and the patient survival.

RESULTS

Among the cohort including 363 patients starting HD therapy, 251 (age 65.8 ± 14.8 years, 93 female/158 male, diabetes 36%) survived at least 1 year after dialysis onset and were followed for 44.9 months. During the first 8 weeks, the TGW decreased by 6.5 ± 5.6% (initial TGW change). The initial TGW change was correlated with IDWG at W12 and W26, and with changes in serum albumin and nPNA (normalized protein equivalent of nitrogen appearance) between HD W1 and W52 (respectively +7.8 and +11.4%). From W8 to W52, the TGW increased by +1.9 ± 7.4% (secondary TGW change). The Kaplan-Meier analysis displayed a significantly better survival in patients above the median (+2.3%) of the secondary TGW change (respectively -3.6 ± 5.2% and +7.6 ± 4.5%). The two groups above and below this median were not different according to age, diabetes or cardiovascular event history but the patients above the median had a significant higher IDWG and protein intake. In the Cox model analysis the patient overall mortality was related to age (p < 0.0001), to the secondary TGW change (p = 0.0001), and to the CRP level at W52 (p < 0.0001).

CONCLUSIONS

The initial fluid removal was related to nutritional markers. The secondary TGW change during the first year of HD treatment calculated after the initial phase of fluid removal was identified as a strong predictor of survival. It was associated with a better food intake whereas the patient case mix was not different. These data highlight the importance of nutrition and food intake in the first year of dialysis therapy and the need for nutritional follow-up and support in incident HD patients. It stresses the need in understanding the key factors associated with food intake in this setting.

Association between blood cadmium levels and malnutrition in peritoneal dialysis

Background

Malnutrition is associated with an increased risk of cardiovascular death and may cause protein-energy wasting in individuals with chronic kidney disease. A previous study demonstrated that blood cadmium levels (BCLs) were associated with malnutrition in maintenance hemodialysis (MHD) patients. However, the correlation between cadmium exposure and malnutrition remains unclear in chronic peritoneal dialysis (CPD) patients. This study examined the possible adverse effects of environmental cadmium exposure in CPD patients.

Methods

A total of 301 CPD patients were enrolled and divided into 3 study groups based on the following BCL tertiles: low (<0.19 μg/L), middle (0.19–0.39 μg/L), and high (>0.39 μg/L). Demographic, hematological, biochemical, and dialysis-related data were obtained for analysis. The analysis also included values of nutritional and inflammatory markers.

Results

The BCLs of CPD patients were lower than those of MHD patients. At baseline, patients in the high BCL group were older and had a higher prevalence of diabetes mellitus but lower serum albumin, creatinine, and phosphate levels than the patients in the other 2 groups. After adjusting for potential variables, stepwise backward multiple linear regression analysis revealed that age and alanine aminotransferase levels were positively associated with logarithmic transformation of BCLs (log BCLs), while serum albumin levels were negatively associated with log BCLs in CPD patients. The log BCLs were a significant determinant (beta coefficient ± standard error = -0.185 ± 0.074; P = 0.013) of nutritional status and significantly associated with the presence of malnutrition (odds ratio = 2.64; 95% confidence interval: 1.07–6.48; P = 0.035) in CPD patients after adjustment for related variables.

Conclusions

BCL is significantly associated with nutritional status and malnutrition in CPD patients. Therefore, it is important for CPD patients to avoid environmental exposure to cadmium such as through smoking and consumption of cadmium-rich foods.

Effects of nutritional parameters on nocturnal blood pressure in patients undergoing hemodialysis

BACKGROUND

Malnutrition is a common problem in uremic patients. It is unclear whether there is an association between the degree of malnutrition and 24-h ambulatory blood pressure patterns in patients undergoing hemodialysis. In the present study, we observed the relationship between the degree of malnutrition and deterioration of the rhythm of diurnal blood pressure, which are both risk factors for cardiovascular morbidity-mortality and associated with hypervolemia.

METHOD

We observed 148 patients undergoing hemodialysis in the Nephrology Department of Celal Bayar University Hospital. All cases were assessed for body weight alterations, dietary food intake, gastrointestinal symptoms, loss of subcutaneous fat and muscle tissue, presence and severity of comorbidities, functional capacity (subjective global assessment), and anthropometric indices. Ambulatory blood pressure measurements were performed for all cases on the day between the two hemodialysis sessions.

RESULTS

We found that the circadian blood pressure rhythm deteriorated in patients with a high-malnutrition score, and that malnutrition was more common and severe in those subjects with the non-dipper and reverse-dipper blood pressure patterns. Malnutrition score was positively correlated with the nighttime systolic and nighttime mean blood pressures and mean 24-h arterial blood pressure (all p ≤ 0.01). We identified a positive correlation between malnutrition score and the reduction in serum albumin and anthropometric indices.

CONCLUSION

This is the first study to demonstrate an association between malnutrition and deterioration in the circadian blood pressure rhythm in a hemodialysis population. Nutritional disturbance is associated with an increase in night-time blood pressure. Low serum albumin levels and hypervolemia may contribute this situation.

Let them eat during dialysis: an overlooked opportunity to improve outcomes in maintenance hemodialysis patients

In individuals with chronic kidney disease, surrogates of protein-energy wasting, including a relatively low serum albumin and fat or muscle wasting, are by far the strongest death risk factor compared with any other condition. There are data to indicate that hypoalbuminemia responds to nutritional interventions, which may save lives in the long run. Monitored, in-center provision of high-protein meals and/or oral nutritional supplements during hemodialysis is a feasible, inexpensive, and patient-friendly strategy despite concerns such as postprandial hypotension, aspiration risk, infection control and hygiene, dialysis staff burden, diabetes and phosphorus control, and financial constraints. Adjunct pharmacologic therapies can be added, including appetite stimulators (megesterol, ghrelin, and mirtazapine), anabolic hormones (testosterone and growth factors), antimyostatin agents, and antioxidative and anti-inflammatory agents (pentoxiphylline and cytokine modulators), to increase efficiency of intradialytic food and oral supplementation, although adequate evidence is still lacking. If more severe hypoalbuminemia (<3.0 g/dL) not amenable to oral interventions prevails, or if a patient is not capable of enteral interventions (e.g., because of swallowing problems), then parenteral interventions such as intradialytic parenteral nutrition can be considered. Given the fact that meals and supplements during hemodialysis would require only a small fraction of the funds currently used for dialysis patients this is also an economically feasible strategy.

Dietary management of chronic kidney disease: protein restriction and beyond

PURPOSE OF REVIEW

More kidney protective strategies are needed to reduce the burden of complete kidney failure from chronic kidney disease (CKD). Clinicians sometimes use protein restriction as kidney protection despite its demonstrated lack of effectiveness in the only large-scale study. Small-scale studies support that dietary acid reduction is kidney-protective, including when done with base-inducing foods like fruits and vegetables. We review these studies in light of current kidney-protective recommendations.

RECENT FINDINGS

Animal models of CKD show that acid-inducing dietary protein exacerbates and base-inducing protein ameliorates nephropathy progression, and that increased intake of acid-inducing but not base-inducing dietary protein exacerbates progression. Clinical studies show that dietary acid reduction with Na-based alkali reduces kidney injury and slows nephropathy progression in patients with CKD and reduced glomerular filtration rate (GFR); base-inducing fruits and vegetables reduce kidney injury in patients with reduced GFR; and base-inducing fruits and vegetables improve metabolic acidosis in CKD.

SUMMARY

Protein type rather than amount might more importantly affect nephropathy progression. Base-inducing foods might be another way to reduce dietary acid, a strategy shown in small studies to slow nephropathy progression. Further studies will determine if CKD patients should be given base-inducing food as part of their management.

Effects of three times weekly eight-hour nocturnal hemodialysis on volume and nutritional status

BACKGROUND

This prospective cohort study compared the changes in body water composition and nutritional parameters measured with multifrequency bioimpedance analysis between 8-hour three times weekly nocturnal hemodialysis (NHD) and 4-hour conventional hemodialysis (CHD) patients.

PATIENTS AND METHODS

55 patients on CHD and 57 patients on NHD were included in the study. Multifrequency bioimpedance analysis was performed at baseline and at the 12th month. The primary outcomes of the study were changes in extracellular water (ECW), fat mass, dry lean mass and phase angle. Secondary outcomes of the study included changes in blood pressure and biochemical parameters related to nutrition and inflammation.

RESULTS

ECW/height values decreased in the NHD group, while they increased in the CHD group. Fat mass, dry lean mass, and serum albumin increased and high sensitive CRP decreased in the NHD group but did not change in the CHD group. When changes in parameters from baseline to the 12th month between the groups were compared, NHD was associated with improvement in volume parameter including ECW/height (difference -0.44 l/m, p < 0.001). Change in blood pressure was not different between the groups, however requirement for antihypertensive medication decreased from 26.5 to 8.5% in the NHD group (p = 0.002). NHD was also associated with increases in fat mass (difference 1.8 kg, p < 0.001), dry lean mass (difference 0.6 kg, p = 0.006), serum albumin (difference 0.19 g/dl, p < 0.001) and cholesterol (difference 18.8 mg, p < 0.001). Phase angle values decreased in the CHD group but did not change in the NHD group (difference between the groups 0.37°, p = 0.04).

CONCLUSION

This study revealed that longer HD facilitates volume control and improves nutritional status.

Associations between bioelectrical impedance parameters and cardiovascular events in chronic dialysis patients

PURPOSE

Malnutrition and fluid overload contribute to the poor cardiovascular prognosis of dialysis patients. Since bioelectrical impedance analysis is an option for the evaluation of body composition and for the monitoring of hydration state, it may assist in the identification of subjects at high cardiovascular risk. The objective of this study was to evaluate the association between bioelectrical impedance parameters and cardiovascular events.

METHODS

The association between bioelectrical impedance parameters and fatal and non-fatal cardiovascular outcome was evaluated in 145 dialysis patients.

RESULTS

The mean age of the population studied was 54.9 ± 15.4 years, 49.7 % were males, and 35.9 % had diabetes. Forty (27.6 %) patients developed cardiovascular events during the 16 months (8; 32) of follow-up. Comparison of patients with and without cardiovascular events revealed higher extracellular mass/body cell mass (ECM/BCM) and extracellular water/total body water ratios and higher C-reactive protein levels in the former. Survival analysis showed that an ECM/BCM ratio >1.2 and a phase angle <6° were associated with poor cardiovascular prognosis. Among nondiabetic patients, these parameters and capacitance were independently associated with cardiovascular events, suggesting that poor nutritional status and fluid overload are associated with the occurrence of these events.

CONCLUSIONS

Phase angle, capacitance and ECM/BCM ratio are valuable parameters for the evaluation of cardiovascular prognosis, supporting the use of bioelectrical impedance for the clinical assessment of dialysis patients.

Transthyretin predicts cardiovascular outcome in hemodialysis patients with type 2 diabetes

OBJECTIVE

BMI and albumin are commonly accepted parameters to recognize wasting in dialysis patients and are powerful predictors of morbidity and mortality. However, both parameters reveal limitations and may not cover the entire range of patients with wasting. The visceral protein transthyretin (TTR) may be helpful in overcoming the diagnostic and prognostic gap. Therefore, the aim of this study was to assess the association of TTR with morbidity and mortality in hemodialysis patients.

RESEARCH DESIGN AND METHODS

The TTR concentration was determined in plasma samples of 1,177 hemodialysis patients with type 2 diabetes. Cox regression analyses were used to determine hazard ratios (HRs) for the risk of cardiovascular end points (CVEs) and mortality according to quartiles of TTR concentration for the total study cohort and the subgroups BMI ≥23 kg/m(2), albumin concentration ≥3.8 g/dL, and a combination of both.

RESULTS

A low TTR concentration was associated with an increased risk for CVE for the total study cohort (HR 1.65 [95% CI 1.27-2.14]), patients with BMI ≥23 kg/m(2) (1.70 [1.22-2.37]), albumin ≥3.8 g/dL (1.68 [1.17-2.42]), and the combination of both (1.69 [1.13-2.53]). Additionally, a low TTR concentration predicted mortality for the total study cohort (1.79 [1.43-2.24]) and patients with BMI ≥23 kg/m(2) (1.46 [1.09-1.95]).

CONCLUSIONS

The current study demonstrated that TTR is a useful predictor for cardiovascular outcome and mortality in diabetic hemodialysis patients. TTR was particularly useful in patients who were not identified to be at risk by BMI or albumin status.

IL-6 levels, nutritional status, and mortality in prevalent hemodialysis patients

BACKGROUND AND OBJECTIVES

The influence of serum IL-6 levels on nutritional status in chronic hemodialysis (HD) patients remains to be elucidated. The present report describes a prospective longitudinal study of IL-6 levels and nutritional parameters to determine whether high IL-6 levels are independently associated with nutritional status over time in a cohort of prevalent hemodialysis patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

85 clinically stable hemodialysis patients (37.6% women), with a mean age of 66.5 ± 10.6 years, were studied after exclusion of patients with BMI < 20 kg/m(2) and/or serum albumin <35 g/L. IL-6, dietary energy and protein intake, and biochemical markers of nutrition and body composition (anthropometry and bioimpedance analysis) were measured at baseline and at 6, 12, 18, and 24 months following enrollment. Observation of this cohort was continued over 2 additional years.

RESULTS

IL-6 levels increased with time in both unadjusted (linear estimate: 2.57 ± 0.44 pg/ml per 2 yrs; P = 0.001) and adjusted models (linear estimate: 2.35 ± 0.57 pg/ml per 2 yrs; P = 0.049). Significant reductions of daily energy intake, laboratory markers (albumin, transferrin, cholesterol, creatinine), and body composition (fat mass) with higher IL-6 levels were observed over the duration of the longitudinal observation period. However, none of the studied parameters were associated with changes in IL-6 levels over time (IL-6-by-time interactions were NS). Furthermore, cumulative incidences of survival were correlated with the baseline serum IL-6 levels (P = 0.004 by log-rank test). Finally, for each pg/ml increase in IL-6 level, the hazard ratio for death from all causes was 1.06 (95% CI 1.01 to 1.10) after adjustment for demographic and clinical parameters.

CONCLUSIONS

Our results suggest that higher serum IL-6 levels are associated with all-cause mortality without additional changes in clinical and laboratory markers of nutritional status in clinically stable HD patients.

Detection of iron deposition in dermal fibrocytes is a useful tool for histologic diagnosis of nephrogenic systemic fibrosis

Nephrogenic systemic fibrosis (NSF) is a fibrotic disease that presents with a history of renal dysfunction. The differential diagnosis generally includes scleromyxedema, systemic sclerosis, and morphea. Especially, scleromyxedema can be extremely difficult to distinguish microscopically. Although the fibrocytes in NSF are often positive for CD34 and procollagen-I, this is not specific for NSF. We identified positive iron staining in the skin of a patient with NSF and investigated whether this was a specific feature among 9 patients with NSF reported in Japan. We found that 6 of 9 patients showed positive iron staining in the dermal fibrocytes. The amount of iron deposition seemed to have no correlation with the degree of fibrosis or duration of the skin lesions but correlated with apparent history of the use of gadolinium-based contrast agents. As controls, skin biopsies from patients with scleromyxedema, morphea, and systemic sclerosis were evaluated by iron staining. None of these control patients showed iron deposition, indicating that positive iron staining may be specific to NSF and can be a useful tool for NSF diagnosis.

Longitudinal study of leptin levels in chronic hemodialysis patients

Background

The influence of serum leptin levels on nutritional status and survival in chronic hemodialysis patients remained to be elucidated. We conducted a prospective longitudinal study of leptin levels and nutritional parameters to determine whether changes of serum leptin levels modify nutritional status and survival in a cohort of prevalent hemodialysis patients.

Methods

Leptin, dietary energy and protein intake, biochemical markers of nutrition and body composition (anthropometry and bioimpedance analysis) were measured at baseline and at 6, 12, 18 and 24 months following enrollment, in 101 prevalent hemodialysis patients (37% women) with a mean age of 64.6 ± 11.5 years. Observation of this cohort was continued over 2 additional years. Changes in repeated measures were evaluated, with adjustment for baseline differences in demographic and clinical parameters.

Results

Significant reduction of leptin levels with time were observed (linear estimate: -2.5010 ± 0.57 ng/ml/2y; p < 0.001) with a more rapid decline in leptin levels in the highest leptin tertile in both unadjusted (p = 0.007) and fully adjusted (p = 0.047) models. A significant reduction in body composition parameters over time was observed, but was not influenced by leptin (leptin-by-time interactions were not significant). No significant associations were noted between leptin levels and changes in dietary protein or energy intake, or laboratory nutritional markers. Finally, cumulative incidences of survival were unaffected by the baseline serum leptin levels.

Conclusions

Thus leptin levels reflect fat mass depots, rather than independently contributing to uremic anorexia or modifying nutritional status and/or survival in chronic hemodialysis patients. The importance of such information is high if leptin is contemplated as a potential therapeutic target in hemodialysis patients.

Diets and enteral supplements for improving outcomes in chronic kidney disease

Protein-energy wasting (PEW), which is manifested by low serum levels of albumin or prealbumin, sarcopenia and weight loss, is one of the strongest predictors of mortality in patients with chronic kidney disease (CKD). Although PEW might be engendered by non-nutritional conditions, such as inflammation or other comorbidities, the question of causality does not refute the effectiveness of dietary interventions and nutritional support in improving outcomes in patients with CKD. The literature indicates that PEW can be mitigated or corrected with an appropriate diet and enteral nutritional support that targets dietary protein intake. In-center meals or oral supplements provided during dialysis therapy are feasible and inexpensive interventions that might improve survival and quality of life in patients with CKD. Dietary requirements and enteral nutritional support must also be considered in patients with CKD and diabetes mellitus, in patients undergoing peritoneal dialysis, renal transplant recipients, and in children with CKD. Adjunctive pharmacological therapies, such as appetite stimulants, anabolic hormones, and antioxidative or anti-inflammatory agents, might augment dietary interventions. Intraperitoneal or intradialytic parenteral nutrition should be considered for patients with PEW whenever enteral interventions are not possible or are ineffective. Controlled trials are needed to better assess the effectiveness of in-center meals and oral supplements.

Low levels of vitamin C in dialysis patients is associated with decreased prealbumin and increased C-reactive protein

BACKGROUND

Subclinical inflammation is a common phenomenon in patients on either continuous ambulatory peritoneal dialysis (CAPD) or maintenance hemodialysis (MHD). We hypothesized that vitamin C had anti-inflammation effect because of its electron offering ability. The current study was designed to test the relationship of plasma vitamin C level and some inflammatory markers.

METHODS

In this cross-sectional study, 284 dialysis patients were recruited, including 117 MHD and 167 CAPD patients. The demographics were recorded. Plasma vitamin C was measured by high-performance liquid chromatography. And we also measured body mass index (BMI, calculated as weight/height(2)), Kt/V, serum albumin, serum prealbumin, high-sensitivity C-reactive protein (hsCRP), ferritin, hemoglobin. The relationships between vitamin C and albumin, pre-albumin and hsCRP levels were tested by Spearman correlation analysis and multiple regression analysis. Patients were classified into three subgroups by vitamin C level according to previous recommendation 12 in MHD and CAPD patients respectively: group A: < 2 ug/ml (< 11.4 umol/l, deficiency), group B: 2-4 ug/ml (11.4-22.8 umol/l, insufficiency) and group C: > 4 ug/ml (> 22.8 umol/l, normal and above).

RESULTS

Patients showed a widely distribution of plasma vitamin C levels in the total 284 dialysis patients. Vitamin C deficiency (< 2 ug/ml) was present in 95(33.45%) and insufficiency (2-4 ug/ml) in 88(30.99%). 73(25.70%) patients had plasma vitamin C levels within normal range (4-14 ug/ml) and 28(9.86%) at higher than normal levels (> 14 ug/ml). The similar proportion of different vitamin C levels was found in both MHD and CAPD groups. Plasma vitamin C level was inversely associated with hsCRP concentration (Spearman r = -0.201, P = 0.001) and positively associated with prealbumin (Spearman r = 0.268, P < 0.001), albumin levels (Spearman r = 0.161, P = 0.007). In multiple linear regression analysis, plasma vitamin C level was inversely associated with log(10)hsCRP (P = 0.048) and positively with prealbumin levels (P = 0.002) adjusted for gender, age, diabetes, modality of dialysis and some other confounding effects.

CONCLUSIONS

The investigation indicates that vitamin C deficiency is common in both MHD patients and CAPD patients. Plasma vitamin C level is positively associated with serum prealbumin level and negatively associated with hsCRP level in both groups. Vitamin C deficiency may play an important role in the increased inflammatory status in dialysis patients. Further studies are needed to determine whether inflammatory status in dialysis patients can be improved by using vitamin C supplements.

Fighting protein-energy wasting in chronic kidney disease: a challenge of complexity

Chronic uremia is often characterized by wasting of muscle and fat mass, which has been defined as protein-energy wasting (PEW), and is responsible for substantial worsening of patient outcome in terms of morbidity and mortality, mostly from cardiovascular events. Despite major advances in patient treatment, nutritional outcome in patients with end-stage renal disease has not improved substantially in recent years. Extensive research in this field has provided plausible explanations for this limitation by indicating that the pathogenesis of PEW in kidney disease is complex and multifactorial. Complexity involves underlying metabolic alterations, including inflammation, oxidative stress, and insulin resistance. In addition, patient heterogeneity is increasing with large numbers of obese individuals as a result of the ongoing obesity epidemics. Several tissues are involved in cross-talk and contribute to metabolic derangements, including adipose tissue, the gut, and the central nervous system, with novel mediators including the gastric hormone ghrelin. Acknowledging its complex pathogenesis may favor the development of novel and more effective therapeutic tools for PEW. These should ideally be effective in treating the underlying common mechanisms of wasting, which appear to include oxidative stress, inflammation, and insulin resistance.

White blood cell count predicts all-cause, cardiovascular disease-cause and infection-cause one-year mortality of maintenance hemodialysis patients

Elevated white blood cell (WBC) counts predict coronary heart disease and all-cause mortality in the general population. Chronic inflammation and malnutrition are associated with increased risk of cardiovascular death in individuals with chronic kidney disease. In this study, we investigated the association between WBC count with inflammation, malnutrition, and mortality in maintenance hemodialysis (MHD) patients. A total of 959 MHD patients were stratified into four equal sized groups based on WBC count. Demographic, hematological, nutritional and inflammatory markers, and biochemical and dialysis-related data were obtained for cross-sectional analysis. All patients were followed for one year to investigate the risks for mortality. The mean WBC count was 6.4 ± 1.8 × 10(3)/µL (range: 2.3-16.3 × 10(3)/µL). Stepwise multiple linear regression analysis indicated a positive correlation between WBC count and inflammation (high-sensitivity C-reactive protein > 3 mg/L). Forty-five patients (4.7%) died within the 1-year study period. Cox multivariate regression analysis demonstrated that total WBC count significantly predicts 1-year mortality due to all-cause (hazard ratio (HR): 1.228, 95% confidence interval (CI): 1.095-1.378; P < 0.001), due to cardiovascular disease (HR: 1.242, 95% CI: 1.046-1.475; P = 0.013) and due to infection (HR: 1.252, 95% CI: 1.066-1.470; P = 0.006). These findings suggest that total WBC count should be measured in future studies that evaluate the clinical outcome of MHD patients and that dialysis patients with elevated WBC counts require further medical attention to reduce risks of mortality.

Wasting in chronic kidney disease

Wasting/cachexia is prevalent among patients with chronic kidney disease (CKD). It is to be distinguished from malnutrition, which is defined as the consequence of insufficient food intake or an improper diet. Malnutrition is characterized by hunger, which is an adaptive response, whereas anorexia is prevalent in patients with wasting/cachexia. Energy expenditure decreases as a protective mechanism in malnutrition whereas it remains inappropriately high in cachexia/wasting. In malnutrition, fat mass is preferentially lost and lean body mass and muscle mass is preserved. In cachexia/wasting, muscle is wasted and fat is relatively underutilized. Restoring adequate food intake or altering the composition of the diet reverses malnutrition. Nutrition supplementation does not totally reverse cachexia/wasting. The diagnostic criteria of cachexia/protein-energy wasting in CKD are considered. The association of wasting surrogates, such as serum albumin and prealbumin, with mortality is strong making them robust outcome predictors. At the patient level, longevity has consistently been observed in patients with CKD who have more muscle and/or fat, who report better appetite and who eat more. Although inadequate nutritional intake may contribute to wasting or cachexia, recent evidence indicates that other factors, including systemic inflammation, perturbations of appetite-controlling hormones from reduced renal clearance, aberrant neuropeptide signaling, insulin and insulin-like growth factor resistance, and metabolic acidosis, may be important in the pathogenesis of CKD-associated wasting. A number of novel therapeutic approaches, such as ghrelin agonists and melanocortin receptor antagonists are currently at the experimental level and await confirmation by randomized controlled clinical trials in patients with CKD-associated cachexia/wasting syndrome.

Relationship between periodontal disease and mortality in patients treated with maintenance hemodialysis

BACKGROUND

The relationship between periodontitis and outcomes in patients treated with long-term hemodialysis is controversial. Our previous work suggests that periodontitis is associated with malnutrition and inflammation. Here, we hypothesize that periodontitis is associated with mortality in hemodialysis patients.

STUDY DESIGN

Prospective observational study.

SETTING & PARTICIPANTS

253 patients undergoing hemodialysis at a single hospital-based dialysis facility.

PREDICTOR

Severity of periodontal disease (mild, moderate, or severe based on oral examination of 6 teeth).

OUTCOMES & MEASUREMENTS

All-cause and cardiovascular mortality during a 6-year follow-up after an oral health examination of index teeth.

RESULTS

During the 6-year follow-up, 102 patients died. Death occurred in 70.6%, 41.8%, and 24.0% of patients with severe, moderate, and mild/no periodontitis, respectively. Using mild/no periodontitis as the reference group and adjustment for demographic characteristics, comorbid conditions, and selected laboratory values, HRs for all-cause mortality were 1.39 (95% CI, 0.83-2.34) and 1.83 (95% CI, 1.04-3.24) for moderate and severe periodontitis, respectively. HRs for cardiovascular mortality were not statistically significant.

LIMITATIONS

Single assessment of periodontal disease severity.

CONCLUSIONS

For patients undergoing long-term hemodialysis, periodontitis is associated with increased risk of death. Clinical trials are required to determine whether treatment of periodontitis decreases mortality.

Prescribed dietary phosphate restriction and survival among hemodialysis patients

BACKGROUND AND OBJECTIVES

Hyperphosphatemia is common among hemodialysis patients. Although prescribed dietary phosphate restriction is a recommended therapy, little is known about the long-term effects on survival.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a post hoc analysis of data from the Hemodialysis Study (n = 1751). Prescribed dietary phosphate was recorded at baseline and annually thereafter. Marginal structural proportional hazard models were fit to estimate the adjusted association between dietary phosphate restriction and mortality in the setting of time-dependent confounding.

RESULTS

At baseline, prescribed daily phosphate was restricted to levels ≤ 870, 871 to 999, 1000, 1001 to 2000 mg, and not restricted in 300, 314, 307, 297, and 533 participants, respectively. More restrictive prescribed dietary phosphate was associated with poorer indices of nutritional status on baseline analyses and a persistently greater need for nutritional supplementation but not longitudinal changes in caloric or protein intake. On marginal structural analysis, there was a stepwise trend toward greater survival with more liberal phosphate prescription, which reached statistical significance among subjects prescribed 1001 to 2000 mg/d and those with no specified phosphate restriction: hazard ratios (95% CIs) 0.73 (0.54 to 0.97) and 0.71 (0.55 to 0.92), respectively. Subgroup analysis suggested a more pronounced survival benefit of liberal dietary phosphate prescription among nonblacks, participants without hyperphosphatemia, and those not receiving activated vitamin D.

CONCLUSIONS

Prescribed dietary phosphate restriction is not associated with improved survival among prevalent hemodialysis patients, and increased level of restriction may be associated with greater mortality particularly in some subgroups.

Unintentional weight loss is an independent predictor of mortality in a hemodialysis population

OBJECTIVE

This study investigated common components of classification of nutrition screening risk in the prediction of clinical end-points (mortality and morbidity) in hemodialysis patients over a 3-year period (2005 to 2008).

DESIGN

This was a retrospective cohort study.

SETTING

This study was conducted at a Hemodialysis centre.

PARTICIPANTS

The study included patients on maintenance hemodialysis in June 2005.

INTERVENTION

Assessment of nutrition risk was carried out using components of Protein-Energy Wasting criteria.

MAIN OUTCOME MEASURE

Clinical outcome at the 3-year follow-up (June 2008) was measured as mortality and morbidity (as unplanned hospital admissions). Risk of mortality was investigated independent of comorbidities, age, gender, ethnicity, and dialysis vintage using Cox proportional hazards model.

RESULTS

A total of 217 patients met the inclusion criteria (143 male [66%]; age, 60.5 ± 15.6 years). Patients who lost ≥5% body weight in the 6 months before the study commenced, had a 3-fold (Hazard Ratio = 3.0; 95% confidence interval: 1.2 to 7.5) independent greater risk of death (P = .02). Low serum albumin (<38 g/L) resulted in higher morbidity and mortality; however, this was not statistically significant when adjusted for confounders. Body mass index was only available in 64% (138 of 217) of the cohort at baseline, and was not related to clinical outcome at the 3-year follow-up.

CONCLUSION

Unintentional weight loss is independently predictive of clinical outcome in this cohort of dialysis patients. It is recommended that nutrition screening tools include weight loss as a key component in classification of risk and for prioritizing patient care.

Blood cadmium level's association with 18-month mortality in diabetic patients with maintenance haemodialysis

BACKGROUND

Cadmium exposure is related to severity of diabetes and diabetes-related organ damage in diabetic patients. Elevated blood cadmium levels (BCLs) are well known in maintenance haemodialysis (MHD) patients but the clinical significance in diabetic MHD patients remains unknown.

METHODS

A total of 212 diabetic MHD patients were enrolled in this 18-month prospective study and were categorized into three equal groups according to the basal BCL: high (> 0.889 μg/L; n = 71), middle (0.373-0.889 μg/L; n = 70) and low (< 0.373 μg/L; n = 71) BCL groups. The mortality and cause of death were recorded and analysed longitudinally.

RESULTS

Patients with high BCL had trends of higher white blood cell counts, glycosylated haemoglobin, phosphate and blood lead levels than other group patients. At the end of the follow-up, 31 patients had died. Kaplan-Meier analysis showed that the high BCL group patients had a higher mortality than other group patients (log-rank test, P = 0.036). Cox multivariate analysis demonstrated that logarithmic BCL was associated with increased hazard ratios (HR) for the all-cause mortality (HR = 2.336, 95% confidence intervals [CI] = 1.099-4.964, P = 0.027) in diabetic MHD patients. Similarly, if the low BCL group was the reference, the high BCL was associated with increased HR for all-cause mortality (HR = 2.865, 95% CI = 1.117-7.353, P = 0.043) in these patients.

CONCLUSIONS

The study results first demonstrated that BCL is associated with increased HR for 18-month all-cause mortality in diabetic MHD patients. Avoiding smoking and high cadmium-containing food may be important in these patients.

Associations between nutritional markers and inflammation in hemodialysis patients

The purpose of this study is to evaluate associations between clinical, laboratory, demographic, and nutritional markers with inflammatory state and malnutrition in hemodialysis (HD) patients. Fifty-two patients on regular HD were evaluated by clinical, demographic, laboratory, and nutritional parameters (food intake, anthropometric measurements, bioelectric impedance, subjective global assessment--SGA and appetite characteristics). Inflammation (serum C-reactive protein >or= 0.9 mg/dl) was present in 13 (25%) and malnutrition (SGA) in 16 (30.7%) patients. Body mass index (BMI), total lymphocytes count, and phase angle were negative and independently associated with malnutrition. Values of BMI >or= 25 kg/m2 were associated with diabetes, positively associated with adipose tissue percentage (BIA) and negatively associated with diastolic blood pressure. Phase angle was positively associated with hematocrit, total lymphocytes count and serum creatinine, and was negatively associated with age. A negative and independent association between muscle mass percentage (BIA) and inflammation was observed. These results suggested that inflammatory state induces muscle mass depletion, while high BMI is associated with diabetes and with lower diastolic blood pressure, a recognized cardiovascular risk factor in uremic patients. Phase angle and SGA were associated with traditional nutritional markers, reinforcing their validity for HD patients.

Blood lead levels association with 18-month all-cause mortality in patients with chronic peritoneal dialysis

BACKGROUND

The clinical significance of blood lead levels (BLLs) in chronic peritoneal dialysis (CPD) patients was undetermined prior to this study.

METHODS

A total of 315 patients on CPD were included in this 18-month prospective study. BLLs measured at baseline were categorized according to a BLL tertile of high (>8.66 microg/dL), middle (5.62-8.66 microg/dL) and low (<5.62 microg/dL) for cross-sectional analyses. Mortality and cause of death were recorded for longitudinal analyses.

RESULTS

At baseline, patients with high BLLs had a trend of higher parathyroid hormone and lower residual renal function than patients in other groups. Stepwise multiple regression analysis found that parathyroid hormone positively correlated and residual renal function negatively correlated with logarithmic-transformed BLLs in CPD patients after other confounders were adjusted. At the end of follow-up, 37 (11.7%) patients had died. Kaplan-Meier analysis showed that patients with high BLLs had greater mortality than those with middle and low BLLs (P = 0.008). Cox multivariate analysis showed that, using the low BLL group as the reference, basal high BLLs (hazard ratio [HR] = 3.745, 95% confidence interval [95% CI] = 1.218-11.494, P = 0.001) and middle BLLs (HR = 1.867, 95% CI = 1.618-2.567, P = 0.001) were associated with increased HR for all-cause mortality for CPD patients. There is a significant trend (P < 0.001) of HR for mortality trend tests among the three study groups.

CONCLUSIONS

BLLs are associated with residual renal function and hyperparathyroidism and are related to increased HR for all-cause 18-month mortality in CPD patients.

[Insulin resistance and inflammation in chronic kidney diseases]

Insulin resistance (IR) and inflammation are now identified as common features in chronic kidney disease (CKD) patients. These metabolic abnormalities are both predictors of adverse cardiovascular (CV) outcome and are associated with worst nutritional status. Unequivocal experimental, epidemiological and clinical evidence produced during the past decade causally links inflammation to the development of metabolic syndrome or the complications that emerge from these pathologies particularly in the context of obesity or type II diabetes patients. These observations lead to the hypothesis of "meta-inflammation" : metabolically triggered inflammation, with a key role played by adipose tissue. In CKD patients, many other factors related with uremia can be causative but the abnormal cytokine and adipokine concentrations and the cluster of metabolic abnormalities push us to think like other metabolic diseases, that adipose tissue dysfunction may be among the pathways that induce inflammation and IR. Therapeutic approaches of traditional CV risk factors have been inconclusive or failed to improve the outcome of these patients. Further studies assessing the impact of renal failure on adipose tissue function and the pathways that are altered in this disease may allow to have therapeutic approaches targetting adipose tissue dysfunction or inflammation.

Assessment of prealbumin in hemodialysis and renal-transplant patients

OBJECTIVE

This study assessed prealbumin in hemodialysis (HD) and renal-transplant (RT) patients, and compared it with other biochemical and anthropometric markers, clinical conditions, and treatment variables.

DESIGN

We used a research design.

PATIENTS

Serum prealbumin was measured in 84 HD patients with a mean age of 60.47 +/- 17.81 years and a mean body mass index (BMI) of 24.38 +/- 4.87 kg/m(2), and in 154 RT patients with a mean age of 44.08 +/- 13.59 years and a mean BMI of 24.97 +/- 3.87 kg/m(2). Renal-transplant patients were divided into three groups, based on year of renal transplantation (first year, first to second year, and third to tenth year). Serum albumin, creatinine, cholesterol, glucose, triglycerides, white blood cells, BMI, midarm circumference, and triceps and biceps skinfolds were measured.

RESULTS

Prealbumin levels were significantly higher in HD patients compared with RT patients. Both groups had prealbumin levels <30 mg/dL, but almost all RT patients in our study had prealbumin levels <20 mg/dL. Gender, age, and presence of anemia, hypertension, and diabetes did not significantly affect prealbumin levels in the two groups. Prealbumin levels were significantly positively correlated with duration of dialysis in the HD group and with albumin in the RT group.

CONCLUSIONS

Hemodialysis patients have higher levels of prealbumin compared with RT patients. Prealbumin levels are below normal range in both groups of patients. Prealbumin reflects nutritional status in RT patients, but is also affected by other factors.

Nutritional Profile and Inflammatory Status of Hemodialysis Patients

BACKGROUND

Malnutrition and abnormal inflammatory markers are prominent features of the uremic syndrome, but associations and repercussions are somewhat controversial.

OBJECTIVE

To determine nutritional and clinical profile of hemodialysis patients, aiming at potential diagnostic recommendations for stable subjects with elevated C-reactive protein.

MATERIAL AND METHOD

DESIGN

Prospective observational cross-sectional clinical study in a stable chronic hemodialysis population;

SETTING

Renal and Nutritional Service of a mid-size charity academic hospital;

PATIENTS

Subjects (n=44) were analyzed concerning nutritional status and C-reactive protein. Some displayed acute infections (Group I, n=9) and others did not (Group II, n=35). Age was 47.0 +/- 16.9 years with 63.6% males. Body mass index (BMI) was 22.2 +/- 3.9 kg/m2, calorie intake was 1262 +/- 601 kcal/day (20.7 +/- 6.7 kcal/kg/day), and protein ingestion was 74.3 +/- 16.6 g protein/day (1.2 g/kg/day);

INTERVENTION

No nutritional supplement or artificial modality of alimentation was employed in this series;

MAIN OUTCOME MEASURES

Subjective global assessment and C-reactive protein.

RESULTS

Malnutrition estimated by subjective global assessment (SGA) was very common (>90%), despite acceptable BMI and serum albumin. C-reactive protein was moderately elevated in 40.9% and was positively associated with SGA and negatively with plasma proteins. Comorbidities were associated positively with extracellular water and negatively with reactance (bioimpedance). When infected versus non-infected cases were analyzed, 100% of the former displayed high CRP concentrations in contrast with 22.9% of remaining patients.

CONCLUSIONS

(1) Malnutrition profile was rather unique, with relatively favorable objective findings (body mass index, serum albumin) and more deranged SGA; (2) Bioimpedance analysis suggested that phase angle could be used as an indicator of nutritional status; (3) Creactive protein was negatively associated with plasma proteins; (4) Infected subjects, although few and displaying moderate clinical troubles, were responsible for most C-reactive protein determinations above 8 mg/L; (5) Investigation of occult infectious foci is advised in these circumstances.

Severity of hypoalbuminemia predicts response to intradialytic parenteral nutrition in hemodialysis patients

BACKGROUND

Intradialytic parenteral nutrition (IDPN) is used infrequently to correct hypoalbuminemia in maintenance hemodialysis (MHD) patients. We hypothesized that the severity of baseline hypoalbuminemia correlates with the success rate of IDPN therapy in MHD patients.

METHODS

In a prospective and contemporary cohort of 196 hypoalbuminemic MHD patients who received IDPN through Pentec Health (Boothwyn, PA), predictors of IDPN response were examined using multivariate logistic regression.

RESULTS

Of 196 hypoalbuminemic MHD patients, 134 had severe hypoalbuminemia, defined as a baseline serum albumin level of less than 3.0 g/dL. The average period of IDPN therapy was 5.8 +/- 2.4 months, S.D. The baseline level of serum albumin was lower in MHD patients who responded to IDPN (2.68 +/- 0.47 g/dL, S.D.). A multivariate logistic regression analysis adjusted the associations for age, gender, diabetes, and IDPN time. The presence of severe hypoalbuminemia (serum albumin, <3.0 g/dL) at baseline was associated with a 2.5 times higher chance of responding to IDPN (95% confidence interval, 1.3 to 4.9; P = .006). The same severe hypoalbuminemia was associated with a 3.5 times increased likelihood of serum albumin correction by at least 0.5 g/dL (95% confidence interval, 1.8 to 6.8; P < .001).

CONCLUSIONS

Improvement of hypoalbuminemia occurs in most hypoalbuminemic MHD patients who receive IDPN therapy. The likelihood and magnitude of the response to IDPN are associated with the severity of baseline hypoalbuminemia. These associations need to be verified in controlled trials.

Association of environmental cadmium exposure with inflammation and malnutrition in maintenance haemodialysis patients

BACKGROUND

Chronic inflammation and malnutrition are associated with increased risk of cardiovascular death, and may cause protein-energy wasting in individuals with chronic kidney disease. Raised blood cadmium (Cd) levels were observed in maintenance haemodialysis (HD) patients in previous studies. However, the correlation of Cd exposure with inflammation and malnutrition remains uncertain. This study examined the possible adverse effects of environmental Cd exposure in maintenance HD patients.

METHODS

A total of 954 maintenance HD patients were enrolled and divided into four equal-sized groups based on blood Cd levels. Geographic, haematological, biochemical and dialysis-related data were obtained. The analysis included values for nutritional and inflammatory markers.

RESULTS

Abnormal blood Cd levels (> or =1 microg/L) were exhibited in 26.8% (256/954) of studied subjects. More subjects in the highest quartile group were malnourished (chi- square = 23.27; P < 0.0001) and had inflammatory changes (chi-square = 13.99; P = 0.0029) than in the lowest quartile group. Stepwise multiple regression analysis revealed a significant inverse correlation between serum albumin and blood Cd levels. Notably, a 10-fold increase in blood Cd levels was associated with a 0.06 g/dL decrease in serum albumin levels (P = 0.0060). Multivariate regression analysis also demonstrated a positive correlation between inflammatory risk (high-sensitivity C-reactive protein >3 mg/L) and blood Cd levels. The risk ratio of inflammation with a 10-fold increase in blood Cd levels was 1.388 (95% CI: 1.025-1.825, P = 0.0336).

CONCLUSIONS

Environmental Cd exposure is significantly associated with malnutrition, inflammation and even protein-energy wasting in maintenance HD patients. It is important for this population to avoid diets with high Cd concentrations and smoking.

Nutritional status evaluation and survival in haemodialysis patients in one centre from Romania

BACKGROUND

Protein-energy wasting is a common complication and an important predictive factor for mortality in chronic dialysis patients. Therefore, nutritional status needs to be regularly assessed in these patients, by using several methods, and, if malnutrition is present, its possible causes should be thoroughly searched for and properly treated.

MATERIAL AND METHODS

In 149 prevalent haemodialysis patients (82 men, mean age 53.9 +/- 13.7 years), we evaluated the nutritional status by anthropometrics [post-dialysis height (H), body weight (BW), body mass index (BMI), mid-arm circumference (MAC), tricipital skin-fold thickness (TST), mid-arm muscle circumference (MAMC), corrected mid-arm muscle area (cMAMA) and three-category subjective global assessment score (SGA)], biochemical tests [protein equivalent of nitrogen appearance (nPNA), and pre-dialysis serum albumin, creatinine, total cholesterol, bicarbonate and haemoglobin (Hb) levels] and bioelectrical impedance analysis (BIA) to estimate body composition [percent body fat (%BF), fat-free mass (%FFM), body cell mass (%BCM), extracellular mass (%ECM) and the phase angle (PhA)].

RESULTS

Age was found to be positively correlated with BMI (P = 0.001), and inversely correlated with %BCM (P = 0.013). Patients with A-category SGA were significantly younger (50.1 versus 63.7 years) than those with B-category SGA. Patients with diabetes had lower %BCM (32.9 versus 35.9%; P = 0.035) and PhA (5.5 versus 6.9 degrees ; P = 0.0007) than those without diabetes. The presence of heart failure was associated with significantly reduced nPNA (1.17 versus 1.34 g/kg day; P = 0.014), MAMC (22.0 versus 23.6 cm(2); P = 0.041), %BCM (33.0 versus 36.1; P = 0.021), PhA (5.8 versus 7.0 degrees ; P = 0.031), serum albumin (39.7 versus 42.4 g/l; P = 0.013) and serum creatinine (8.1 versus 9.4 mg/dl; P = 0.010), and with a higher percent of B-category SGA (47.8% versus 22.6%; P = 0.019). Eleven deaths (7.4%) occurred during the follow-up period. Among general factors, age >or= 55, the presence of diabetes, and dialysis vintage <2 years were associated with significantly reduced survival. Among nutritional factors, B-category SGA, nPNA <1.2 g/kg day, %BF <15% and PhA <6 degrees significantly predicted mortality in both Kaplan-Meier and Cox analyses. The most important risk factor appeared to be nPNA; for every 0.1 g/kg day increase in nPNA, death risk decreased by 15%.

CONCLUSIONS

In our haemodialysis patients, advancing age, diabetes and heart failure were associated with worse nutritional status, as estimated by anthropometry, biochemical markers and BIA. Age >or=55 years, the presence of diabetes, nPNA <1.2 g/kg day, lower SGA score, %BF <15% and PhA <6 degrees were associated with significantly increased death risk.

Association of serum total iron-binding capacity and its changes over time with nutritional and clinical outcomes in hemodialysis patients

Serum transferrin, estimated by total iron-binding capacity (TIBC), may be a marker of protein-energy wasting (PEW) in maintenance hemodialysis (MHD) patients. We hypothesized that low TIBC or its fall over time is associated with poor clinical outcomes. In 807 MHD patients in a prospective 5-year cohort, associations of TIBC and its changes over time with outcomes were examined after adjustment for case-mix and markers of iron stores and malnutrition-inflammation including serum interleukin-6, iron and ferritin. Patients with serum TIBC >or=250 mg/dl had higher body mass index, triceps and biceps skinfolds and mid-arm muscle circumference and higher serum levels of iron but lower ferritin and inflammatory markers. Some SF-36 quality of life (QoL) components were worse in the lowest and/or highest TIBC groups. Mortality was incrementally higher in lower TIBC levels (p-trend <0.001). Adjusted death hazard ratio was 1.75 (95% CI: 1.00-3.05, p = 0.05) for TIBC <150 compared to TIBC of 200-250 mg/dl. A fall in TIBC >20 mg/dl over 6 months was associated with a death hazard ratio of 1.57 (95% CI: 1.04-2.36, p = 0.03) compared to the stable TIBC group. Hence, low baseline serum TIBC is associated with iron deficiency, PEW, inflammation, poor QoL and mortality, and its decline over time is independently associated with increased death risk.

Association of serum prealbumin and its changes over time with clinical outcomes and survival in patients receiving hemodialysis

BACKGROUND

In patients receiving maintenance hemodialysis (MHD), a low serum prealbumin is an indicator of protein-energy wasting.

OBJECTIVE

We hypothesized that baseline serum prealbumin correlates independently with health-related quality of life (QoL) and death and that its change over time is a robust mortality predictor.

DESIGN

Associations and survival predictability of serum prealbumin at baseline and its changes over 6 mo were examined in a 5-y (2001-2006) cohort of 798 patients receiving MHD.

RESULTS

Patients with serum prealbumin >or= 40 mg/dL had greater mid-arm muscle circumference but lower percentage of total body fat. Both serum interleukin-6 and dietary protein intake correlated independently with serum prealbumin. Measures of QoL indicated better physical health, physical function, and functionality with higher prealbumin concentrations. Although baseline prealbumin was not superior to albumin in predicting survival, in both all and normoalbuminemic (albumin >or= 3.5 g/dL; n = 655) patients, prealbumin < 20 mg/dL was associated with higher death risk in adjusted models, but further adjustments for inflammatory cytokines mitigated the associations. In 412 patients with baseline prealbumin between 20 and 40 mg/dL whose serum prealbumin was remeasured after 6 mo, a >or=10-mg/dL fall resulted in a death hazard ratio of 1.37 (95% CI: 1.02, 1.85; P = 0.03) after adjustment for baseline measures, including inflammatory markers.

CONCLUSIONS

Even though baseline serum prealbumin may not be superior to albumin in predicting mortality in MHD patients, prealbumin concentrations <20 mg/dL are associated with death risk even in normoalbuminemic patients, and a fall in serum prealbumin over 6 mo is independently associated with increased death risk.

Postprandial intradialytic dysglycaemia and diabetes in maintenance haemodialysis patients

BACKGROUND

Although the risk of developing dysglycaemia has been investigated in different communities this incidence is poorly studied in patients on maintenance haemodialysis (MHD).

MATERIALS AND METHODS

In a multicentre observational cohort study the occurrence of dysglycaemia was assessed in 239 primary normoglycaemic end stage renal disease (ERSD) patients on MHD. Dysglycaemia (fasting blood glucose > 110 mg dL(-1), > 140 mg dL(-1) 2 h after food intake) or diabetes (fasting blood glucose > 126 mg dL(-1) or > 200 mg dL(-1) at any time) were defined according to WHO criteria and cases were compared with age matched controls within the cohort.

RESULTS

Dysglycaemia was found in 82 primary normoglycaemic ESRD patients (34%) within 31 months after initiation of MHD. In 31 of these patients type 2 diabetes was diagnosed. When compared with matched control MHD patients differences in body mass index (BMI), HbA1c and postprandial blood glucose were detectable (P < 0.05). Increments in 0.1% of HbA1c were related with 11% higher odds for dysglycaemia (P = 0.002). In a subgroup of 36 primary normoglycaemic MHD patients who developed dysglycaemia event-free survival was 64%, 53%, 31%, 17% and 11% after 1, 2, 3, 4 and 5 years of haemodialysis treatment.

CONCLUSION

Onset of dysglycaemia or diabetes is frequent in ESRD patients after onset of chronic haemodialysis. Routine measurement of blood glucose before and after haemodialysis should be implemented as a standard of care during MHD.

Assessment of plasma antioxidant status in hemodialysis patients

The risk of atherosclerosis and cancer is high in patients on hemodialysis. A breakdown in the natural balance between the activity of the body's antioxidant system and the production of oxidizing agents is suggested to be involved. To investigate the oxidative stress status in Iranian hemodialytic patients, in this study we evaluated plasma vitamin E, malondialdehyde (MDA), reduced glutathione (GSH), and ferric reducing antioxidant power (FRAP) levels in these patients. Twenty-four hemodialytic patients and 24 control subjects (age and sex matched) were included in this study. Each patient was under dialysis, three times per week, four hours in each session. Before and after dialysis, blood was taken for biochemical measurements as well as oxidative stress tests. There was a significant decrease in FRAP and GSH levels after dialysis comparing to before treatment levels. MDA was increased by dialysis and vitamin E levels were less in dialytic patients, both before and after treatment, compared to controls. This study indicates that there is a significant level of oxidative stress in chronic renal patients and this stress is augmented by dialysis. Antioxidant therapy could be considered in these patients.

Iron indices and vitamin D receptor polymorphisms in hemodialysis patients

Cardiovascular disease caused by accelerated atherosclerosis is the major determinant of morbidity and mortality in chronic kidney disease patients. Vitamin D and its analogs provide survival benefit for hemodialysis (HD) patients. Vitamin D exerts its effects through the vitamin D receptor (VDR) that is coded for by a gene showing several polymorphisms that, in turn, are associated with a variety of diseases and differential responses to vitamin D. In this study, we evaluated the association between 4 VDR polymorphisms (ie, those identified by the restriction enzymes BsmI, ApaI, TaqI, and FokI) and iron indices (serum iron, transferrin, transferrin saturation, and ferritin) in 88 hemodialysis patients routinely treated with vitamin D. The absence or presence of the BsmI, ApaI, TaqI, and FokI restriction sites were denominated B and b, A and a, T and t, F and f, respectively. Our results show that in HD patients with transferrin saturation <20%, the F allele was more frequent than in HD patients with transferrin saturation >20% (P = .03). This relationship may provide a link between VDR alleles and iron and nutritional markers, which are highly predictive variables of cardiovascular morbidity and mortality in hemodialysis patients.

A review of albumin binding in CKD

Hypoalbuminemia is associated with excess mortality in patients with kidney disease. Albumin is an important oxidant scavenger and an abundant carrier protein for numerous endogenous and exogenous compounds. Several specific binding sites for anionic, neutral, and cationic ligands were described. Overall, the extent of binding depends on the ligand and albumin concentration, albumin-binding affinity, and presence of competing ligands. Chronic kidney disease affects all these determinants. This may result in altered pharmacokinetics and increased risk of toxicity. Renal clearance of albumin-bound solutes mainly depends on tubular clearance. Dialytic clearance by means of conventional hemodialysis/hemofiltration and peritoneal dialysis is limited. Other epuration techniques combining hemodialysis with adsorption have been developed. However, the benefit of these techniques remains to be proved.

Blood lead levels, malnutrition, inflammation, and mortality in patients with diabetes treated by long-term hemodialysis

BACKGROUND

Blood lead levels (BLLs) are associated with mortality in the general population. The clinical significance of BLLs in long-term hemodialysis (HD) patients with diabetes is unknown.

STUDY DESIGN

A cross-sectional and 1-year prospective study.

SETTINGS & PARTICIPANTS

211 patients with diabetes on long-term HD therapy at 3 centers.

PREDICTOR

BLLs measured before HD at baseline, categorized as abnormal (>20 microg/dL), high normal (10 to 20 microg/dL), and low normal (<10 microg/dL).

OUTCOMES & MEASUREMENTS

Malnutrition, defined as serum albumin level less than 3.6 g/dL, and inflammation, defined as high-sensitivity C-reactive protein level greater than 3 mg/dL, for cross-sectional analyses. Mortality and cause of death for longitudinal analyses.

RESULTS

34, 112, and 65 patients had abnormal, high-normal, and low-normal BLLs at baseline. At baseline, patients with abnormal BLLs had a greater proportion of malnutrition (14.7% versus 1.5% and 11.6%; P = 0.01) and inflammation (76.5% versus 52.3% and 50.9%; P = 0.01) than those with low- and high-normal BLLs. Backward stepwise regression analysis found that high-sensitivity C-reactive protein level correlated positively and albumin level correlated negatively with BLLs after other confounders were adjusted. At the end of follow-up, 16 patients had died. Kaplan-Meier analysis showed that patients with an abnormal BLL had greater mortality than those with low and low-normal BLLs (P = 0.004).

LIMITATIONS

Small sample size, sparse outcomes, and limited follow-up.

CONCLUSIONS

BLL may contribute to inflammation and nutritional status in long-term HD patients with diabetes on long-term HD therapy and may relate to 1-year mortality in these patients.

How common is malnutrition in ESRD? New approaches to diagnosis of malnutrition

Malnutrition is associated with increased mortality in the dialysis population. However, the true prevalence of malnutrition is not known due to the lack of simple diagnostic strategies for assessing nutritional status. Internationally recommended diagnostic algorithms mainly include the one-time assessment of nutritional indices and comparison to normal reference values. However, these indices do not take into account the dynamics of malnutrition which is associated with a progressive change in body composition and loss in muscle mass. Longitudinal assessment of changes in body composition may be necessary to improve timing and accuracy of the diagnosis of undernutrition. Whole-body as well as segmental multifrequency bioimpedance spectroscopy have been shown to yield good estimates of total body or segmental (limb) muscle mass. Bioimpedance spectroscopy is a relatively inexpensive, non-invasive, painless method requiring only minimal operator training, which in the near future may prove useful for nutritional management of ESRD patients.