Relationship of Normalized Protein Catabolic Rate with Nutrition Status and Long-Term Survival in Peritoneal Dialysis Patients.

The normalized protein catabolic rate (nPCR) reflects daily dietary protein intake in stable dialysis patients. In peritoneal dialysis (PD) patients, reports about the importance of nPCR as marker of nutrition and outcome have been inconsistent. The objective of the present study was to investigate the relationships of nPCR with body composition parameters, micronutrient electrolytes, and long-term survival in PD patients. From November 2000 to May 2008, 57 PD patients were enrolled in the study. On enrollment, demographic, clinical, and biochemical data were recorded. Patients were followed through September 2011. Mean age of the patients was 56 years, and 61% were of African descent. Mean and maximum follow-up were 2.83 years and 11 years respectively. Mean daily nPCR was 0.944 g/kg. The nPCR correlated directly with albumin (r = 0.34, p = 0.012), magnesium (r = 0.48, p < 0.0001), phosphorus (r = 0.42, p = 0.02), and the phase angle body composition parameter (r = 0.26, p = 0.049). Compared with patients whose enrollment daily nPCR was less than 0.8 g/kg, those with an enrollment daily nPCR of 0.8 g/kg or more experienced significantly better 11-year cumulative survival (p = 0.04). In multivariate Cox regression analysis with adjustment for confounding variables, nPCR was an independent predictor of all-cause mortality (p = 0.018). In conclusion, lower nPCR is associated with poorer nutrition status and increased risk of all-cause mortality in PD patients followed for up to 11 years.

Serum magnesium concentration is a significant predictor of mortality in peritoneal dialysis patients.

We previously reported that lower serum magnesium is associated with poorer nutrition status, impaired cellular health, and increased inflammation in peritoneal dialysis (PD) patients. The present study was designed to investigate the prognostic value of serum magnesium for mortality in PD patients. From November 2000 to July 2008, the study enrolled 62 patients, recording their demographic, clinical, and biochemical data. Patients were followed to September 2011. Mean age of the patients was 55 +/- 16 years, and in this cohort, 55% were women, 63% were African American, and 25% had diabetes. Mean serum magnesium was 1.597 +/- 0.28 mEq/L. Maximum follow-up was 10.8 years. During the follow-up period, 27 patients died (43.5%). Serum magnesium was significantly higher in the patients who survived than in those who did not (1.757 mEq/L vs. 1.515 mEq/L, p = 0.04). Patients were then stratified by enrollment magnesium. After 10.8 years of observation, cumulative survival was significantly better in patients with an enrollment serum magnesium greater than 1.6 mEq/L than in patients with an enrollment serum magnesium of 1.6 mEq/L or less (p = 0.04). Multivariate Cox regression analysis revealed that serum magnesium is a significant predictor of mortality (relative risk: 0.984; p = 0.048) after adjusting for age, race, sex, diabetes, and months on dialysis at enrollment. In conclusion, lower serum magnesium is a significant predictor of higher mortality in PD patients. Factors affecting the serum magnesium concentration in PD patients should be investigated in more detail.

Relationship between alkaline phosphatase and all-cause mortality in peritoneal dialysis patients.

Elevated levels of serum alkaline phosphatase (AlkPhos) have been reported to be associated with increased mortality risk in hemodialysis (HD) patients. We examined the association of serum AlkPhos with all-cause mortality in our PD patients. The study enrolled 90 PD patients beginning in 1995. On enrollment, demographics and clinical and biochemical data were recorded. Patients were followed to September 2011. Mean age of the enrollees was 52 years, with 61% being women, and most (81%) being of African descent. Mean and median AlkPhos were 135 U/L and 113 U/L respectively. Mean and maximum follow-up were 2.61 and 16 years respectively. As expected, AlkPhos correlated directly with serum intact parathyroid hormone (r = 0.36, p = 0.003). In a Cox multivariate regression analysis with adjustment for confounding variables, AlkPhos as a continuous (relative risk: 1.016; p = 0.004) anda categorical variable [> 120 U/L and < or = 120 U/L (relative risk: 6.0; p = 0.03)] remained a significant independent predictor of mortality. For each unit increase in enrollment AlkPhos, there was a 1.6% increase in the relative risk of death. Elevated serum AlkPhos is significantly and independently associated with increased mortality risk in our PD patients followed for up to 16 years. AlkPhos should be evaluated prospectively as a potential therapeutic target in clinical practice.

Dialysis vintage, body composition, and survival in peritoneal dialysis patients.

The relationship between dialysis vintage (length of time on dialysis), body composition, and survival has been reported in hemodialysis patients. In the present study, we examined the association ofdialysis vintage with body composition and survival in peritoneal dialysis (PD) patients. At enrollment, body composition in 65 PD patients was determined by bioelectrical impedance analysis. Patients (mean age at enrollment: 54 years) were followed for up to 11 years maximum. At enrollment, the mean, median, and maximum dialysis vintages were 51, 34, and 261 months respectively. After adjusting for age, race, sex, and diabetes status, dialysis vintage was indirectly correlated (partial correlation coefficients) with body weight (r = -0.40, p = 0.001), body mass index (r = -0.40, p = 0.002), body surface area (r = -0.39, p = 0.002), body cell mass (r = -0.39, p = 0.002), total body fat weight (r = -0.30, p = 0.02), and fat percentage of body weight (r = -0.31, p = 0.018), and directly correlated with extracellular mass to body cell mass ratio (r = 0.27, p = 0.039). The observed cumulative survival was significantly higher (p = 0.007) in patients with a dialysis vintage at enrollment of 35 months or less, than in patients with dialysis vintage at enrollment of more than 35 months. In the multivariate Cox regression analysis, adjusting for age, race, sex, and diabetes, dialysis vintage at enrollment remained an independent predictor of mortality (relative risk: 1.010; p = 0.002). Increase in relative risk of death with increasing dialysis vintage may be partly explained by the association of vintage with unfavorable changes in body composition and the nutrition status of patients over time.

Treatment of secondary hyperparathyroidism in ESRD: a 2-year, single-center crossover study.

Secondary hyperparathyroidism (SHPT) is a common complication of chronic kidney disease. The management of SHPT commonly involves vitamin D, either calcitriol or newer analogs (paricalcitol or doxercalciferol), along with dietary phosphorus restriction and phosphate binding agents. Published reports have suggested that treatment with paricalcitol in hemodialyzed (HD) patients offers a morbidity or mortality advantage in comparison with treatment with calcitriol. We have recently reported that switching from calcitriol to paricalcitol resulted in a lower serum calcium and calcium-phosphorus product (Ca x P product), as well as lower parathyroid hormone (PTH) and alkaline phosphatase during 6 months of serial treatment. We converted all HD patients in our large urban dialysis center from calcitriol to paricalcitol using a 1:3 conversion ratio, on the basis of published data. Comparisons of individual patient mean biochemical values, as well as episodes of hypercalcemia and elevated Ca x P product, were made after adjusting for equivalent doses. In addition, we recorded the number of missed doses during two years of therapy. No patient in this study had received a calcimimetic before or during the study period. Fifty-nine patients were treated with calcitriol for at least 12 months and then completed 12 months of paricalcitol. Conversion from calcitriol to paricalcitol resulted in lower serum calcium (P=0.0003), lower serum phosphorus (P=0.027), lower Ca x P product (P=0.003), reduced PTH (P=0.001) and reduced serum alkaline phosphatase (P=0.0005). Most dramatically, there was a highly significant difference in the number of missed doses (P<0.0001) during the treatments. This 2-year single-center study, comparing long-term calcitriol with paricalcitol treatment in the same HD patients, extends our previous findings, offers new information regarding single episodes of potentially adverse biochemical effects related to vitamin D therapy, and provides several clues that may explain the outcome advantages suggested by previously published retrospective analyses of large dialysis provider-pooled databases.

Extracellular mass/body cell mass ratio is an independent predictor of survival in peritoneal dialysis patients.

Malnutrition is a strong predictor of mortality in peritoneal dialysis (PD) patients. Extracellular mass (ECM) contains all the metabolically inactive, whereas body cell mass (BCM) contains all the metabolically active, tissues of the body. ECM/BCM ratio is a highly sensitive index of malnutrition. The objective of this study was to explore the relationship between ECM/BCM ratio and survival in PD patients. We enrolled 62 patients from November 2000 to July 2008. On enrollment, demographic, clinical, and biochemical data were recorded. Bioimpedance analysis (BIA) was used to determine ECM and BCM in PD patients. Patients were followed up to November 2008. Mean age was 54+/-16 (s.d.) years; female, 55%; African Americans, 65%; diabetic, 24%. Mean ECM/BCM ratio was 1.206+/-0.197 (range: 0.73-1.62). Diabetics had higher ECM/BCM ratio than nondiabetics (1.29 vs 1.18, P=0.04). ECM/BCM ratio correlated directly with age (r=0.38, P=0.002) and inversely with serum albumin (r=-0.43, P=0.001), creatinine (-0.24, P=0.08), blood urea nitrogen (r=-0.26, P=0.06), and total protein (r=-0.31, P=0.026). Using multivariate Cox regression analysis, adjusting for age, race, gender, diabetes, and human immunodeficiency virus status, enrollment ECM/BCM ratio was a significant independent predictor of mortality (relative risk=1.035, P=0.018). For every 10% increase in the ECM/BCM ratio, the relative risk of death was increased by about 35%. In conclusion, BIA-derived enrollment ECM/BCM ratio, a marker of malnutrition, was an independent predictor of long-term survival in PD patients.

Serum fructosamine versus glycosylated hemoglobin as an index of glycemic control, hospitalization, and infection in diabetic hemodialysis patients.

Diabetes is the most common cause of end-stage renal disease and an important risk factor for morbidity and mortality in dialysis patients. Glycemic control, utilizing serial measurement of glycosylated hemoglobin (HbA1c), is generally recommended to limit end-organ damage, including cardiovascular morbidity and mortality. We, along with others, have previously suggested that HbA1c may not be a reliable measure of glycemic control in dialysis patients, and have therefore explored the use of serum fructosamine (SF) as an alternative marker. The objective of this study was to compare HbA1c levels with SF in monitoring glycemic control and associated morbidity (infection and hospitalization) in diabetic patients in a large urban hemodialysis (HD) center. We enrolled 100 diabetic HD patients and followed them up prospectively for 3 years. Data on demographics, as well as biochemical and clinical data, including hospitalizations and infections, were recorded. The mean age was 63 years. In all 54% were women and the majority were African Americans (72%). As expected, HbA1c and albumin-corrected fructosamine (AlbF) levels were highly correlated and both were significantly associated with serum glucose. AlbF, however, was more highly correlated with mean glucose values when less than 150 mg/dl and was a more useful predictor of morbidity. By univariate logistic regression and by Poisson regression analysis, AlbF, but not HbA1c, was a significant predictor of hospitalization. Additionally, in patients dialyzed by arteriovenous (AV) access (that is, excluding those dialyzed via vascular catheters), AlbF, but not HbA1c, was a significant predictor of infection. In conclusion, AlbF is as reliable a marker as HbA1c for glycemic control in diabetic patients on HD, and may be advantageous for patients with serum glucose in a desirable therapeutic range (<150 mg/dl). In addition, AlbF, but not HbA1c, is associated with morbidity (hospitalizations and infections) in diabetic patients on HD.

Enrollment fluid status is independently associated with long-term survival of peritoneal dialysis patients.

Fluid overload is a common complication in peritoneal dialysis (PD) patients. The prognostic importance of enrollment fluid status in long-term PD patients remains to be investigated. The objective of the present study was to investigate the prognostic importance of enrollment fluid status in the long-term survival of PD patients. We enrolled 53 PD patients (mean age: 53 years) from November 2000 to February 2006. On enrollment, demographic, clinical, and biochemical data were recorded. Bioelectrical impedance analysis (BIA) was used to determine the fluid status of PD patients, including extracellular water (ECW), intracellular water (ICW), and total body water (TBW). Fluid status was corrected for body surface area (BSA): ECW-BSA, ICW-BSA, and TBW-BSA respectively. Patients were followed to January 2008. The ECW-BSA correlated negatively with albumin, a marker of nutrition (r = -0.53, p < 0.0001). The ICW/ECW ratio (r = 0.36, p = 0.018) correlated directly and the ECW/ TBW ratio (r = -0.36, p = 0.019) correlated negatively with creatinine. Patients who survived during the study period had a significantly lower ECW-BSA (8.29 L/m2 vs. 9.91 L/m2, p = 0.001) than did those who did not survive. Patients with enrollment ECW-BSA below 9 L/m2 had a significantly better 7-year cumulative survival (Kaplan-Meier) than did patients with a ECW-BSA of 9 L/m2 or more (p = 0.019). Using multivariate Cox regression analysis, adjusting for age, race, diabetes, human immunodeficiency virus (HIV) status, and months on dialysis at enrollment, ECW-BSA was a significant independent predictor of mortality (relative risk: 1.50; p = 0.03). In conclusion, ECW-BSA was a significant independent predictor of long-term survival in PD patients.

Pulmonary hypertension in peritoneal dialysis patients.

The information available in the literature regarding pulmonary hypertension (PH) in peritoneal dialysis (PD) patients is limited. The objective of the present study was to examine the prevalence and characteristics of PH in PD patients. We retrospectively collected the clinical profile, echocardiographic (ECHO) findings, and biochemical data for 36 PD patients for which ECHO findings were available. We compared characteristics between patients with and without PH. We found PH, defined as pulmonary arterial pressure (PAP) > or = 35 mmHg, in 15 patients. The prevalence of PH was 42%. Mean age (+/- standard deviation) of the patients with and without PH was 58 +/- 15 years and 52 +/- 15 years respectively (p = 0.30). Mean PAP of the PH patients was 43.8 +/- 9.0 mmHg (range: 35-65 mmHg). Patients with PH had a lower ejection fraction than did patients without PH (46.3% +/- 19.8% vs. 56.5% +/- 11.8% respectively, p = 0.07). Patients with PH also had a higher prevalence of global hypokinesia (60% vs. 29%, p = 0. 059) and dilated left ventricular chamber (53% vs. 19%, p = 0.03). In PH patients, body mass index (24 +/- 4.5 kg/m2 vs. 28 +/- 5.0 kg/m2, p = 0.024), normalized protein catabolic rate (0. 78 +/- 0.21 g/kg vs. 0.95 +/- 0.27 g/kg daily, p = 0.049), and ferritin (226 +/- 210 ng/mL vs. 873 +/- 965 ng/mL, p = 0.005) were significantly lower and lactate dehydrogenase was higher (264 +/- 99 U/L vs. 206 +/- 79 U/L, p = 0.06) than in patients without PH. We observed no significant differences in race or sex, incidence of hypertension or cardiovascular disease, or vitamin D analog use between the two groups of patients. During the study period, 60% of PH patients and 38% of patients without PH died (p = 0.19). Values of PAP correlated directly with serum levels of phosphorus (r = 0.44, p = 0.02), CaxP product (r = 0.40, p = 0.04), and parathyroid hormone (r = 0.42, p = 0.03). Of continuous ambulatory PD and continuous cycling PD patients, 21% and 55% respectively had PH (p = 0. 049). In PD patients, PH is highly prevalent and may be associated with higher mortality risk.

Relationship of peritoneal transport rate and dialysis adequacy with inflammation in peritoneal dialysis patients.

Inflammation, dialysis adequacy, and peritoneal transport rate (PTR) influence clinical outcomes in peritoneal dialysis (PD) patients. The present study examined the relationship of C-reactive protein (CRP), a marker of inflammation, to PTR and residual renal function (RRF) in PD patients. We recorded the baseline dialysate-to-plasma creatinine (D/P Cr) of 210 PD patients starting in 1986. In a subgroup of 42 patients, we serially measured high-sensitivity CRP levels and.dialysis adequacy, including weekly Kt/V urea and creatinine clearance (CCr), starting in May 2003. The patients were followed to January 2006. Mean age was 53 +/- 16 (standard deviation) years, and 70% of the patients were African American. Enrollment mean and median CRP levels were 13.53 +/- 20.8 (range: 0.2-95.8) and 7.15 mg/L respectively. Mean weekly residual CCr and Kt/V during follow-up were 7.11 +/- 15.47 L/1.73 m2 and 0.14 +/- 0.30 respectively. The mean enrollment D/P Cr was 0.649 +/- 0.12 (range: 0.429-0.954). Patients with CRP > 10 mg/L had significantly lower weekly residual CCr (0.59 L/1.73 m2 vs. 10.1 L/1.73 m2, p = 0.01), residual Kt/V (0.01 vs. 0.20, p = 0.01), total CCr (56 L/1.73 m2 vs. 62 L/1.73 m2, p= 0.047), and total Kt/V (2.09 vs. 2.49, p = 0.001) than did those with CRP < or = 10 mg/L. Levels of CRP correlated negatively with weekly residual CCr (r = -0.42, p = 0.006), residual Kt/V (r = -0.43, p = 0.006), and total Kt/V (r = -0.44, p = 0.004). Enrollment D/P Cr was inversely correlated with serum albumin (r = -0.24, p = 0.001) and directly correlated with peritoneal protein loss (r = 0.34, p = 0.028). Higher enrollment D/P Cr was associated with lower observed cumulative survival (Kaplan-Meier) in PD patients. However D/P Cr was not an independent predictor of long-term survival in PD patients. Using multivariate Cox regression analysis, and including D/P Cr and residual Kt/V in the model, enrollment CRP was an independent predictor of mortality (relative risk = 1.036, p = 0.018). We conclude that elevated CRP is associated with lower RRF As a predictor of mortality, CRP may be better than RRF and D/P Cr.

Association between C-reactive protein and clinical outcomes in peritoneal dialysis patients.

An elevated level of C-reactive protein (CRP), which is a marker of inflammation, is a risk factor for morbidity and mortality in the general population and in dialysis patients. Recently, the relationship between inflammation and nutrition status has received much attention. Serum prealbumin is a highly sensitive marker of nutrition and survival in dialysis patients. The objective of the present study was to evaluate the prognostic value and clinical correlates of CRP in peritoneal dialysis (PD) patients. Using retrospective chart review, we collected demographic, clinical, and laboratory data on 66 PD patients for the period June 2001 to January 2005. High-sensitivity CRP (hs-CRP) levels were measured in a subgroup of 32 patients starting in May 2003. Over the study period, prealbumin and CRP were assayed serially by the immunoturbidimetric method. Mean age (+/- standard deviation) of the patients was 55 +/- 15 years, and 73% were African American. Mean and median enrollment CRP were 15.2 +/- 24 mg/L (range: 4.2 - 149.5 mg/L) and 6.45 mg/L respectively. Mean and median enrollment hs-CRP were 15.3 +/- 23.5 mg/L (range: 0.2 - 96 mg/L) and 6.55 mg/L respectively. Enrollment CRP was elevated (215 mg/L) in 29% of the patients, and hs-CRP was elevated (> or = mg/L) in 63% of the patients. Enrollment CRP was strongly correlated with hs-CRP (r = 0.7, p < 0.0001). The presence of diabetes (22 mg/L vs. 7.8 mg/L, p = 0.02), infection and inflammatory conditions (44.9 mg/L vs. 11.6 mg/L, p = 0.001), and lower levels of markers of nutrition such as prealbumin (r = -0.47, p < 0.0001) and creatinine (r = 0.35, p = 0.006) were associated with a higher level of CRP. Enrollment hs-CRP was a significant predictor of mortality in PD patients (relative risk = 1.044, p = 0.023). The observed cumulative survival (Kaplan-Meier) of patients with hs-CRP <15 mg/L was significantly better (p = 0.007) than was the survival of patients with a hs-CRP > or =15 mg/L. In a multivariate regression analysis, serum prealbumin was the best and only significant predictor of CRP level (beta = -0.37, p = 0.005). Elevated CRP was associated with infection and inflammation. Therefore, routine testing of hs-CRP in PD patients should be considered.

Survival experience of peritoneal dialysis patients with human immunodeficiency virus: a 17-year retrospective study.

Human immunodeficiency virus (HIV)-related renal disease is the third-leading cause of end-stage renal disease (ESRD) among African Americans aged 20-64 years. The number of HIV-infected (HIV+) patients reaching ESRD will increase exponentially over the next decade. Because of significant improvements in therapy and management during the last ten years, survival of HIV+ patients has improved. The survival experience of very long-term HIV+ peritoneal dialysis (PD) patients remains to be investigated. The objective of the present study was to examine the important differences in clinical and laboratory parameters between HIV+ and HIV-negative (HIV-) PD patients. To assess the factors associated with better survival in HIV+ PD patients, we retrospectively reviewed the charts of 488 PD patients, including 53 HIV+ patients, for the period 1987 to September 2004. We collected demographic, clinical, and laboratory data, including CD4 cell counts and history of hospitalizations and peritonitis. Maximum survival of HIV+ PD patients was 12.5 years as compared with 15.87 years in HIV-patients. Not surprisingly, HIV was a strong independent predictor of mortality in PD patients [relative risk (RR) = 3.09, p < 0.0001]. In HIV+ patients, higher CD4 counts at the initiation of dialysis were strongly associated with better survival (RR = 0.10 and p < 0.0001, > or =200 cells/mm3 vs. < or =50 cells/mm3). In univariate analysis, use of highly active antiretroviral therapy (HAART) was associated with significantly improved survival in HIV+ PD patients. Patients treated with I or 2 drugs had a 4.3-times higher mortality risk than those who received HAART therapy (p = 0.012). Independent associations were seen between HIV and younger age, African American race, male sex, and lower serum albumin. The rates of hospitalization (p < 0.0001) and peritonitis (p < 0.01) were significantly higher in HIV+ patients than in HIV-patients. Very long-term survival of HIV+ patients with chronic renal failure is possible on PD therapy. Morbidity and mortality of these patients may be improved with HAART therapy, better nutrition, and treatment of peritonitis.

Cinacalcet for secondary hyperparathyroidism in patients receiving hemodialysis.

BACKGROUND: Treatment of secondary hyperparathyroidism with vitamin D and calcium in patients receiving dialysis is often complicated by hypercalcemia and hyperphosphatemia, which may contribute to cardiovascular disease and adverse clinical outcomes. Calcimimetics target the calcium-sensing receptor and lower parathyroid hormone levels without increasing calcium and phosphorus levels. We report the results of two identical randomized, double-blind, placebo-controlled trials evaluating the safety and effectiveness of the calcimimetic agent cinacalcet hydrochloride. METHODS: Patients who were receiving hemodialysis and who had inadequately controlled secondary hyperparathyroidism despite standard treatment were randomly assigned to receive cinacalcet (371 patients) or placebo (370 patients) for 26 weeks. Once-daily doses were increased from 30 mg to 180 mg to achieve intact parathyroid hormone levels of 250 pg per milliliter or less. The primary end point was the percentage of patients with values in this range during a 14-week efficacy-assessment phase. RESULTS: Forty-three percent of the cinacalcet group reached the primary end point, as compared with 5 percent of the placebo group (P<0.001). Overall, mean parathyroid hormone values decreased 43 percent in those receiving cinacalcet but increased 9 percent in the placebo group (P<0.001). The serum calcium-phosphorus product declined by 15 percent in the cinacalcet group and remained unchanged in the placebo group (P<0.001). Cinacalcet effectively reduced parathyroid hormone levels independently of disease severity or changes in vitamin D sterol dose. CONCLUSIONS: Cinacalcet lowers parathyroid hormone levels and improves calcium-phosphorus homeostasis in patients receiving hemodialysis who have uncontrolled secondary hyperparathyroidism.

Relationship of bioelectrical impedance parameters to nutrition and survival in peritoneal dialysis patients.

BACKGROUND: Malnutrition is highly prevalent in peritoneal dialysis (PD) patients and is associated with higher mortality in these patients. In this study, we have prospectively examined the relationship of bioimpedance indexes to the nutritional status and survival in PD patients. METHODS: We enrolled 48 PD patients beginning in November 2000. On enrollment, bioelectrical impedance analysis (BIA) (BIA-101; RJL/Akern, Clinton Township, MI, USA) was performed and monthly blood was analyzed for biochemical markers, including prealbumin. Patients were followed until April 2003. RESULTS: The mean age of PD patients was 51 +/- 15 (SD) years. Fifty-eight percent of the patients were female and 23% of the patients were diabetic. Mean body mass index (BMI) was 25.7 +/- 5.0 kg/m2. Mean resistance, reactance, and phase angle were 521 +/- 104 ohms, 57 +/- 19 ohms, and 6.16 +/- 1.6 degrees, respectively. During the study period, 8 patients (17%) expired. The Kaplan-Meier method was used to compute observed survival. The cumulative observed survival of PD patients with enrollment phase angle greater than or equal to 6 degrees was significantly higher (P = 0.008) than that of patients with phase angle less than 6. Using Cox's multivariate regression analysis, phase angle was an independent predictor (relative risk = 0.39, P = 0.027) of more than two years' survival in PD patients. Serum prealbumin was directly correlated with phase angle (r = 0.54, P < 0.0001), reactance (r = 0.55, P < 0.0001), and resistance (r = 0.29, P = 0.06). CONCLUSION: BIA indexes reflect nutritional status and may be useful in monitoring nutritional status in PD patients. Phase angle is a strong prognostic index in PD patients. It is useful to incorporate prealbumin and BIA parameters in the regular assessment of PD patients, whose survival may be improved by better management of malnutrition and overall health status.

The safety and efficacy of an accelerated iron sucrose dosing regimen in patients with chronic kidney disease.

BACKGROUND: Provision of adequate iron to support erythropoiesis in patients with chronic kidney disease (CKD) is time consuming and may present adherence problems for patients in the outpatient setting. We studied an accelerated regimen of high-dose intravenous iron sucrose therapy in a cohort of iron-deficient, anemic CKD patients. METHODS: Intravenous iron sucrose 500 mg was infused over three hours on two consecutive days in 107 CKD patients (glomerular filtration rate, 32.3 +/- 19.6 mL/min/1.73m2, baseline hemoglobin 10.2 +/- 1.7 g/dL). Iron indices (transferrin saturation, ferritin) were measured at baseline and at two and seven days after completion of the iron regimen. Blood pressures were monitored immediately prior to, and hourly throughout the iron sucrose infusions. RESULTS: Transferrin saturation and serum ferritin increased from 18.5 +/- 8.5% and 177 +/- 123.8 ng/mL at baseline to 40.2 +/- 22.3% and 811 +/- 294.1 ng/mL in 102 evaluated patients (P < 0.015). In 55 patients with additional measurements at 7 days post-dosing, the transferrin saturation and ferritin had fallen to 26.3 +/- 10.6% and 691 +/- 261.8 ng/mL (P < 0.015 compared to two days' post-dose). Blood pressure rose slightly, but not significantly, throughout the infusions, and altering the infusion rate was not necessary. Two patients had seven adverse events that were considered related to iron sucrose. CONCLUSION: An accelerated regimen of high-dose intravenous iron sucrose therapy in CKD patients is safe and effective in restoring iron stores, and may potentially save time and improve patient adherence.

Malnutrition and inflammation in peritoneal dialysis patients.

BACKGROUND: Malnutrition, cardiovascular disease, and heightened inflammation are highly prevalent in dialysis patients, and major contributors to morbidity and mortality. We have investigated the inter-relationship between malnutrition and inflammation, and their impact on morbidity and mortality in peritoneal dialysis (PD) patients. METHOD: We enrolled 63 PD patients beginning in November 2000, and measured C-reactive protein (CRP) and various nutritional markers, including prealbumin. RESULTS: CRP level was elevated in 29% of the PD patients. Diabetics had higher CRP than non-diabetics (24 vs. 9.3 mg/L, P = 0.016). Patients who were hospitalized during the study had higher enrollment CRP (16 vs. 12.5 mg/L, P = 0.05) and lower enrollment albumin (3.5 vs. 3.9 g/dL, P = 0.002), blood urea nitrogen (BUN) (40 vs. 49 mg/dL, P = 0.034), and protein catabolic rate (nPCR) (0.88 vs. 1.0 g/kg/day, P = 0.02) than those who were not hospitalized. Enrollment level of CRP was inversely correlated with nutritional markers prealbumin (r = -0.5, P < 0.0001) and creatinine (r =-0.35, P < 0.01). After adjusting for age, race, gender, diabetes, and CRP level, prealbumin continued to correlate with other nutritional markers. There was a trend toward association of elevated CRP with all-cause mortality in PD patients. CONCLUSION: It is useful to incorporate prealbumin and CRP in the regular assessment of PD patients, whose survival may be improved by better management of malnutrition and inflammation.

Analysis of metabolic parameters as predictors of risk in the RENAAL study.

OBJECTIVE: Metabolic factors such as glycemic control, hyperlipidemia, and hyperkalemia are important considerations in the treatment of patients with type 2 diabetes and nephropathy. In the RENAAL (Reduction of End Points in Type 2 Diabetes With the Angiotensin II Antagonist Losartan) study, losartan reduced renal outcomes in the patient population. This post hoc analysis of the RENAAL study reports the effects of losartan on selected metabolic parameters and assesses the relationship between baseline values of metabolic parameters and the primary composite end point or end-stage renal disease (ESRD). RESEARCH DESIGN AND METHODS: Glycemic control (HbA(1c)) and serum lipid, uric acid, and potassium levels were compared between the losartan and placebo groups over time, and baseline levels were correlated with the risk of reaching the primary composite end point (doubling of serum creatinine, ESRD, or death) or ESRD alone. RESULTS: Losartan did not adversely affect glycemic control or serum lipid levels. Losartan-treated patients had lower total (227.4 vs. 195.4 mg/dl) and LDL (142.2 vs. 111.7 mg/dl) cholesterol. Losartan was associated with a mean increase of up to 0.3 mEq/l in serum potassium levels; however, the rate of hyperkalemia-related discontinuation was similar between the placebo and losartan groups. Univariate analysis revealed that baseline total and LDL cholesterol and triglyceride levels were associated with increased risk of developing the primary composite end point. Similarly, total and LDL cholesterol were also associated with increased risk of developing ESRD. CONCLUSIONS: Overall, losartan was well tolerated by patients with type 2 diabetes and nephropathy and was associated with a favorable effect on the metabolic profile of this population.

Usefulness of bioelectrical impedance analysis in monitoring nutrition status and survival of peritoneal dialysis patients.

Malnutrition is highly prevalent in peritoneal dialysis (PD) patients and is associated with higher mortality. Lower serum levels of markers of nutrition--such as albumin, creatinine, prealbumin, and total cholesterol--are important risk factors in PD patients. Usefulness of bioimpedance analysis (BIA) in hemodialysis (HD) patients has been reported. In the present study, we prospectively examined the relationship of bioimpedance indexes to the nutrition status and survival of 45 PD patients who were followed for more than 1 year. On patient enrollment, a BIA was performed (Bioelectrical Impedance Analyzer, Model BIA-101: RJL Systems, Clinton Township, MI, U.S.A.). Monthly blood was analyzed for biochemical markers. The mean age of the study group was 50 +/- 15 years. Of the 45 patients, 56% were female and 24% were diabetic. Mean body mass index was 25.7 +/- 5.1. Mean resistance, reactance, capacitance, and phase angle were 524 +/- 106 omega 57 +/- 20 omega, 678 +/- 223 pF, and 6.2 +/- 1.7 degrees respectively. Patients with diabetes had lower capacitance (555 pF vs. 713 pF, p = 0.007) and phase angle (5.35 degrees vs. 6.4 degrees, p = 0.05) than patients without diabetes. During the study period, 4 patients died. Patients who survived had higher capacitance (486 +/- 163 pF vs. 697 +/- 218 pF, p = 0.07) and phase angle (4.65 +/- 0.73 degrees, vs. 6.34 +/- 1.67 degrees, p = 0.008) than those who did not survive. The Kaplan-Meier method was used to compute observed survival. The cumulative observed survival of PD patients with an enrollment phase angle > or = 6 degrees was significantly (p = 0.01) higher than that of patients with an enrollment phase angle < 6 degrees. Reactance was directly correlated with albumin (r = 0.52, p < 0.0001) and total protein (r = 0.44, p < 0.05). Capacitance was directly correlated with body mass index (r = 0.35, p < 0.05), albumin (r = 0.32, p < 0.05), and blood urea nitrogen (BUN) (r = 0.44, p < 0.01), and inversely correlated with body weight (r = -0.51, p < 0.0001). Phase angle was directly correlated with all of the biochemical markers of nutrition, such as albumin (r = 0.54, p < 0.01), total protein (r = 0.38, p < 0.05), creatinine (r = 0.28, p < 0.01), and BUN (r = 0.39, p < 0.05). By stepwise multivariate regression analysis, body weight (beta = -0.60, p < 0.0001) and total protein (beta = 0.32, p = 0.012) were significant determinants of resistance. Body weight (beta = -0.31, p = 0.02) and albumin (beta = 0.59, p < 0.0001) were significant predictors of reactance. Serum albumin (beta = 0.53, p < 0.0001) was the only best predictor of phase angle in PD patients. The BIA indices reflect nutrition status in PD patients, and may be useful in monitoring nutrition interventions.