Concept: Blood urea nitrogen
Does long-term creatine supplementation impair kidney function in resistance-trained individuals consuming a high-protein diet?
- Journal of the International Society of Sports Nutrition
- Published over 6 years ago
BACKGROUND: The aim of this study was to determine the effects of creatine supplementation on kidney function in resistance-trained individuals ingesting a high-protein diet. METHODS: A randomized, double-blind, placebo-controlled trial was performed. The participants were randomly allocated to receive either creatine (20 g/d for 5 d followed by 5 g/d throughout the trial) or placebo for 12 weeks. All of the participants were engaged in resistance training and consumed a high-protein diet (i.e., >= 1.2 g/Kg/d). Subjects were assessed at baseline (Pre) and after 12 weeks (Post). Glomerular filtration rate was measured by 51Cr-EDTA clearance. Additionally, blood samples and a 24-h urine collection were obtained for other kidney function assessments. RESULTS: No significant differences were observed for 51Cr-EDTA clearance throughout the trial (Creatine: Pre 101.42 +/- 13.11, Post 108.78 +/- 14.41 mL/min/1.73m2; Placebo: Pre 103.29 +/- 17.64, Post 106.68 +/- 16.05 mL/min/1.73m2; group x time interaction: F = 0.21, p = 0.64). Creatinine clearance, serum and urinary urea, electrolytes, proteinuria, and albuminuria remained virtually unchanged. CONCLUSIONS: A 12-week creatine supplementation protocol did not affect kidney function in resistance-trained healthy individuals consuming a high-protein diet; thus reinforcing the safety of this dietary supplement.Trial registration: ClinicalTrials.gov NCT01817673.
Background Ultrafiltration is an alternative strategy to diuretic therapy for the treatment of patients with acute decompensated heart failure. Little is known about the efficacy and safety of ultrafiltration in patients with acute decompensated heart failure complicated by persistent congestion and worsened renal function. Methods We randomly assigned a total of 188 patients with acute decompensated heart failure, worsened renal function, and persistent congestion to a strategy of stepped pharmacologic therapy (94 patients) or ultrafiltration (94 patients). The primary end point was the bivariate change from baseline in the serum creatinine level and body weight, as assessed 96 hours after random assignment. Patients were followed for 60 days. Results Ultrafiltration was inferior to pharmacologic therapy with respect to the bivariate end point of the change in the serum creatinine level and body weight 96 hours after enrollment (P=0.003), owing primarily to an increase in the creatinine level in the ultrafiltration group. At 96 hours, the mean change in the creatinine level was -0.04±0.53 mg per deciliter (-3.5±46.9 μmol per liter) in the pharmacologic-therapy group, as compared with +0.23±0.70 mg per deciliter (20.3±61.9 μmol per liter) in the ultrafiltration group (P=0.003). There was no significant difference in weight loss 96 hours after enrollment between patients in the pharmacologic-therapy group and those in the ultrafiltration group (a loss of 5.5±5.1 kg [12.1±11.3 lb] and 5.7±3.9 kg [12.6±8.5 lb], respectively; P=0.58). A higher percentage of patients in the ultrafiltration group than in the pharmacologic-therapy group had a serious adverse event (72% vs. 57%, P=0.03). Conclusions In a randomized trial involving patients hospitalized for acute decompensated heart failure, worsened renal function, and persistent congestion, the use of a stepped pharmacologic-therapy algorithm was superior to a strategy of ultrafiltration for the preservation of renal function at 96 hours, with a similar amount of weight loss with the two approaches. Ultrafiltration was associated with a higher rate of adverse events. (Funded by the National Heart, Lung, and Blood Institute; ClinicalTrials.gov number, NCT00608491 .).
Background In a previous trial involving patients with early autosomal dominant polycystic kidney disease (ADPKD; estimated creatinine clearance, ≥60 ml per minute), the vasopressin V2-receptor antagonist tolvaptan slowed the growth in total kidney volume and the decline in the estimated glomerular filtration rate (GFR) but also caused more elevations in aminotransferase and bilirubin levels. The efficacy and safety of tolvaptan in patients with later-stage ADPKD are unknown. Methods We conducted a phase 3, randomized withdrawal, multicenter, placebo-controlled, double-blind trial. After an 8-week prerandomization period that included sequential placebo and tolvaptan run-in phases, during which each patient’s ability to take tolvaptan without dose-limiting side effects was assessed, 1370 patients with ADPKD who were either 18 to 55 years of age with an estimated GFR of 25 to 65 ml per minute per 1.73 m(2) of body-surface area or 56 to 65 years of age with an estimated GFR of 25 to 44 ml per minute per 1.73 m(2) were randomly assigned in a 1:1 ratio to receive tolvaptan or placebo for 12 months. The primary end point was the change in the estimated GFR from baseline to follow-up, with adjustment for the exact duration that each patient participated (interpolated to 1 year). Safety assessments were conducted monthly. Results The change from baseline in the estimated GFR was -2.34 ml per minute per 1.73 m(2) (95% confidence interval [CI], -2.81 to -1.87) in the tolvaptan group, as compared with -3.61 ml per minute per 1.73 m(2) (95% CI, -4.08 to -3.14) in the placebo group (difference, 1.27 ml per minute per 1.73 m(2); 95% CI, 0.86 to 1.68; P<0.001). Elevations in the alanine aminotransferase level (to >3 times the upper limit of the normal range) occurred in 38 of 681 patients (5.6%) in the tolvaptan group and in 8 of 685 (1.2%) in the placebo group. Elevations in the aminotransferase level were reversible after stopping tolvaptan. No elevations in the bilirubin level of more than twice the upper limit of the normal range were detected. Conclusions Tolvaptan resulted in a slower decline than placebo in the estimated GFR over a 1-year period in patients with later-stage ADPKD. (Funded by Otsuka Pharmaceuticals and Otsuka Pharmaceutical Development and Commercialization; REPRISE ClinicalTrials.gov number, NCT02160145 .).
Experimental evidence suggests that higher levels of urea may increase insulin resistance and suppress insulin secretion. However, whether higher levels of blood urea nitrogen (BUN) are associated with increased risk of incident diabetes mellitus in humans is not known. To study this, we built a national cohort of 1,337,452 United States Veterans without diabetes to characterize the association of BUN and risk of incident diabetes. Over a median follow-up of 4.93 years, there were 172,913 cases of incident diabetes. In joint risk models of estimated glomerular filtration rate (eGFR) and BUN. there was no association between eGFR and the risk of incident diabetes in those with a BUN of 25 mg/dl or less. However, the risk was significantly increased in those with a BUN over 25 mg/dl at all eGFR levels, even in those with an eGFR of 60 ml/min/1.73m2 or more (hazard ratio 1.27; confidence interval 1.24-1.31). The risk of incident diabetes was highest in those with BUN over 25 mg/dL and an eGFR under 15 ml/min/1.73m2 (1.68; 1.51-1.87). Spline analyses of the relationship between BUN and risk of incident diabetes showed that risk was progressively higher as BUN increased. In models where eGFR was included as a continuous covariate, compared to a BUN of 25 mg/dl or less, a BUN over 25 mg/dl was associated with increased risk of incident diabetes (1.23; 1.21-1.25). Every 10 ml/min/1.73m2 decrease in eGFR was not associated with risk of incident diabetes (1.00; 1.00-1.01). Two-stage residual inclusion analyses showed that, independent of the impact of eGFR, every 10 mg/dL increase in BUN concentration was associated with increased risk of incident diabetes (1.15; 1.14-1.16). Thus, higher levels of BUN are associated with increased risk of incident diabetes mellitus.
BACKGROUND: Incorporation of the solubilizing excipient, sulfobutylether-beta-cyclodextrin (SBECD), in the intravenous (IV) formulation of voriconazole has resulted in the recommendation that this formulation be used with caution in patients with creatinine clearances (Clcr) < 50 mL/min. This study evaluated the safety of IV voriconazole compared with two other IV antifungals not containing SBECD in patients with compromised renal function. METHODS: A total of 128 patients aged 11--93 years who had a baseline Clcr < 50 mL/min between January 1, 2007 and December 31, 2010 were identified from a database of a university-affiliated inpatient healthcare system; of these, 55 patients received caspofungin, 54 patients received fluconazole, and 19 patients received voriconazole. Changes in serum creatinine (Scr) and Clcr levels while on therapy were compared with baseline values and between groups. RESULTS: The groups had similar characteristics apart from the larger proportion of females that received fluconazole. Baseline Scr was higher in those receiving caspofungin, but maximal increases of Scr and decreases in Clcr were greatest for the fluconazole group. Acute kidney injury (AKI), assessed by RIFLE criteria, was more frequent in the fluconazole vs. the caspofungin group (p < 0.01); incidence of AKI in the voriconazole group was not significantly different than found in the other two groups. The infecting organism was a predictor of AKI and formulation with SBECD was not. CONCLUSIONS: Treatment of fungal infections in patients with compromised renal function with an SBECD-containing antifungal agent was not associated with AKI in clinical practice. Since the infecting organism was associated with AKI, decision on which antifungal to use should be determined by susceptibilities to the organism and not the incorporation of SBECD in the IV formulation.
Lactobacillus plantarum (L. plantarum) is a well-known probiotic among the ingested-microorganism probiotics (i.e., ingested microorganisms associated with beneficial effects for the host). However, few studies have examined the effects of L. plantarum TWK10 (LP10) supplementation on exercise performance, physical fatigue, and gut microbial profile. Male Institute of Cancer Research (ICR) strain mice were divided into three groups (n = 8 per group) for oral administration of LP10 for six weeks at 0, 2.05 × 10⁸, or 1.03 × 10⁸ colony-forming units/kg/day, designated the vehicle, LP10-1X and LP10-5X groups, respectively. LP10 significantly decreased final body weight and increased relative muscle weight (%). LP10 supplementation dose-dependently increased grip strength (p < 0.0001) and endurance swimming time (p < 0.001) and decreased levels of serum lactate (p < 0.0001), ammonia (p < 0.0001), creatine kinase (p = 0.0118), and glucose (p = 0.0151) after acute exercise challenge. The number of type I fibers (slow muscle) in gastrocnemius muscle significantly increased with LP10 treatment. In addition, serum levels of albumin, blood urea nitrogen, creatinine, and triacylglycerol significantly decreased with LP10 treatment. Long-term supplementation with LP10 may increase muscle mass, enhance energy harvesting, and have health-promotion, performance-improvement, and anti-fatigue effects.
Background The course of autosomal dominant polycystic kidney disease (ADPKD) is often associated with pain, hypertension, and kidney failure. Preclinical studies indicated that vasopressin V(2)-receptor antagonists inhibit cyst growth and slow the decline of kidney function. Methods In this phase 3, multicenter, double-blind, placebo-controlled, 3-year trial, we randomly assigned 1445 patients, 18 to 50 years of age, who had ADPKD with a total kidney volume of 750 ml or more and an estimated creatinine clearance of 60 ml per minute or more, in a 2:1 ratio to receive tolvaptan, a V(2)-receptor antagonist, at the highest of three twice-daily dose regimens that the patient found tolerable, or placebo. The primary outcome was the annual rate of change in the total kidney volume. Sequential secondary end points included a composite of time to clinical progression (defined as worsening kidney function, kidney pain, hypertension, and albuminuria) and rate of kidney-function decline. Results Over a 3-year period, the increase in total kidney volume in the tolvaptan group was 2.8% per year (95% confidence interval [CI], 2.5 to 3.1), versus 5.5% per year in the placebo group (95% CI, 5.1 to 6.0; P<0.001). The composite end point favored tolvaptan over placebo (44 vs. 50 events per 100 follow-up-years, P=0.01), with lower rates of worsening kidney function (2 vs. 5 events per 100 person-years of follow-up, P<0.001) and kidney pain (5 vs. 7 events per 100 person-years of follow-up, P=0.007). Tolvaptan was associated with a slower decline in kidney function (reciprocal of the serum creatinine level, -2.61 [mg per milliliter](-1) per year vs. -3.81 [mg per milliliter](-1) per year; P<0.001). There were fewer ADPKD-related adverse events in the tolvaptan group but more events related to aquaresis (excretion of electrolyte-free water) and hepatic adverse events unrelated to ADPKD, contributing to a higher discontinuation rate (23%, vs. 14% in the placebo group). Conclusions Tolvaptan, as compared with placebo, slowed the increase in total kidney volume and the decline in kidney function over a 3-year period in patients with ADPKD but was associated with a higher discontinuation rate, owing to adverse events. (Funded by Otsuka Pharmaceuticals and Otsuka Pharmaceutical Development and Commercialization; TEMPO 3:4 ClinicalTrials.gov number, NCT00428948 .).
Background Relatively high plasma levels of soluble urokinase-type plasminogen activator receptor (suPAR) have been associated with focal segmental glomerulosclerosis and poor clinical outcomes in patients with various conditions. It is unknown whether elevated suPAR levels in patients with normal kidney function are associated with future decline in the estimated glomerular filtration rate (eGFR) and with incident chronic kidney disease. Methods We measured plasma suPAR levels in 3683 persons enrolled in the Emory Cardiovascular Biobank (mean age, 63 years; 65% men; median suPAR level, 3040 pg per milliliter) and determined renal function at enrollment and at subsequent visits in 2292 persons. The relationship between suPAR levels and the eGFR at baseline, the change in the eGFR over time, and the development of chronic kidney disease (eGFR <60 ml per minute per 1.73 m(2) of body-surface area) were analyzed with the use of linear mixed models and Cox regression after adjustment for demographic and clinical variables. Results A higher suPAR level at baseline was associated with a greater decline in the eGFR during follow-up; the annual change in the eGFR was -0.9 ml per minute per 1.73 m(2) among participants in the lowest quartile of suPAR levels as compared with -4.2 ml per minute per 1.73 m(2) among participants in the highest quartile (P<0.001). The 921 participants with a normal eGFR (≥90 ml per minute per 1.73 m(2)) at baseline had the largest suPAR-related decline in the eGFR. In 1335 participants with a baseline eGFR of at least 60 ml per minute per 1.73 m(2), the risk of progression to chronic kidney disease in the highest quartile of suPAR levels was 3.13 times as high (95% confidence interval, 2.11 to 4.65) as that in the lowest quartile. Conclusions An elevated level of suPAR was independently associated with incident chronic kidney disease and an accelerated decline in the eGFR in the groups studied. (Funded by the Abraham J. and Phyllis Katz Foundation and others.).
More than 1 million heart failure hospitalizations occur annually, and congestion is the predominant cause. Rehospitalizations for recurrent congestion portend poor outcomes independently of age and renal function. Persistent congestion trumps serum creatinine increases in predicting adverse heart failure outcomes. No decongestive pharmacological therapy has reduced these harmful consequences. Simplified ultrafiltration devices permit fluid removal in lower-acuity hospital settings, but with conflicting results regarding safety and efficacy. Ultrafiltration performed at fixed rates after onset of therapy-induced increased serum creatinine was not superior to standard care and resulted in more complications. In contrast, compared with diuretic agents, some data suggest that adjustment of ultrafiltration rates to patients' vital signs and renal function may be associated with more effective decongestion and fewer heart failure events. Essential aspects of ultrafiltration remain poorly defined. Further research is urgently needed, given the burden of congestion and data suggesting sustained benefits of early and adjustable ultrafiltration.
To determine the effect of foods with added fiber on blood urea nitrogen (BUN) and serum creatinine concentrations in patients with chronic kidney disease (CKD).