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Background/Aims: In this corollary analysis of the EXCITE study, we looked at possible differences in baseline risk factors and mortality between subjects excluded from the trial because non-eligible (n=216) or because eligible but refusing to participate (n=116). Methods: Baseline characteristics and mortality data were recorded. Survival and independent predictors of mortality were assessed by Kaplan-Meier and Cox regression analyses. Results: The incidence rate of mortality was higher in non-eligible vs. eligible non-randomized patients (21.0 vs. 10.9 deaths/100 persons-year; P<0.001). The crude excess risk of death in non-eligible patients (HR 1.96; 95% CI 1.36 to 2.77; P<0.001) was reduced after adjustment for risk factors which differed in the two cohorts including age, blood pressure, phosphate, CRP, smoking, diabetes, triglycerides, cardiovascular comorbidities and history of neoplasia (HR 1.60; 95% CI 1.10 to 2.35; P=0.017) and almost nullified after including in the same model also information on deambulation impairment (HR 1.16; 95% CI 0.75 to 1.80; P=0.513). Conclusions: Deambulation ability mostly explains the difference in survival rate in non-eligible and eligible non-randomized patients in the EXCITE trial. Extending data analyses and outcome reporting also to subjects not taking part in a trial may be helpful to assess the representability of the study population. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: Scarce physical activity predicts shorter survival in dialysis patients. However, the relationship between physical (motor) fitness and clinical outcomes has never been tested in these patients. Methods: We tested the predictive power of an established metric of motor fitness, the Six-Minute Walking Test (6MWT), for death, cardiovascular events and hospitalization in 296 dialysis patients who took part in the trial EXCITE (ClinicalTrials.gov Identifier: NCT01255969). Results: During follow up 69 patients died, 90 had fatal and non-fatal cardiovascular events, 159 were hospitalized and 182 patients had the composite outcome. In multivariate Cox models - including the study allocation arm and classical and non-classical risk factors - an increase of 20 walked metres during the 6MWT was associated to a 6% reduction of the risk for the composite end-point (P=0.001) and a similar relationship existed between the 6MWT, mortality (P<0.001) and hospitalizations (P=0.03). A similar trend was observed for cardiovascular events but this relationship did not reach statistical significance (P=0.09). Conclusions: Poor physical performance predicts a high risk of mortality, cardiovascular events and hospitalizations in dialysis patients. Future studies, including phase-2 EXCITE, will assess whether improving motor fitness may translate into better clinical outcomes in this high risk population. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Obestatin plays a key role in the process of energy balance maintenance with an anorectic effect. The main aim of the study was to evaluate obestatin in uremic patients to determine whether it is correlated with nutritional and inflammatory status. Methods: We studied plasma obestatin in uremic patients (n = 50) undergoing hemodialysis therapy and in healthy subjects. Plasma obestatin was measured using an ELISA kit. Results: Obestatin levels in uremic patients were lower than in healthy subjects (p < 0.0001). Patients with a body mass index (BMI) >23 had lower obestatin levels than those with a BMI <23 (p = 0.001). After multivariate analysis, direct correlations were maintained between obestatin and high-sensitivity C-reactive protein (β = 0.68, p < 0.0001) and total alkaline phosphatases (β = 0.30, p = 0.03), while inverse correlations were found with iron (β = -0.32, p = 0.002) and calcium-phosphorous product (β = -0.40, p = 0.001). Conclusions: Based on the present observational data, obestatin might be implicated in the inflammatory state and the disturbances of calcium/phosphate metabolism of hemodialysis patients. However, further studies are warranted to determine whether this hormone plays a key role in contributing to malnutrition and to the chronic inflammatory process. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Nephropathic subjects show an increased tendency to develop cardiovascular diseases, mainly as the consequence of several risk factors including increased oxidative stress, inflammation, physical inactivity, anemia, vascular calcification, and endothelial dysfunction. The alterations in lipid metabolism represent a relatively lesser important cause of genesis and progression of atherosclerosis. Unfortunately, in these patients the atherogenic potential of dyslipidemia may depend more on apolipoproteins than on lipid abnormalities, and may not always be recognized by measurement of plasma lipids alone. The aim of this review was therefore to analyze the main lipid alterations that can occur in nephropathic patients, as well as their causes and their effects on the cardiovascular system. The clinical evidence and recommendations for the use of lipid-regulating drugs in patients with chronic kidney disease, nephrotic syndrome, in patients undergoing hemo- and peritoneal dialysis and in transplanted patients was also reviewed. Moreover, we analyzed the link between dyslipidemia and kidney disease onset and progression and the role of statins in preventing it. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: Renal tubulointerstitium plays an important role in the development and progression of diabetic nephropathy. Methods: With the present study, we aimed at evaluating the levels of neutrophil gelatinase-associated lipocalin (NGAL), a tubular stress protein, in serum (sNGAL) and urine (uNGAL) from a cohort of 56 patients with type 2 diabetes mellitus categorized into three groups (normoalbuminuria, microalbuminuria and diabetic nephropathy). Results: All groups showed increased NGAL values with respect to controls; interestingly, increased NGAL levels were already found in diabetic patients without early signs of glomerular damage (normoalbuminuric). Both sNGAL and uNGAL increased in parallel with the severity of renal disease, reaching higher levels in patients with manifest diabetic nephropathy. The assessment of Pearson coefficient evidenced significant relationships between sNGAL and, respectively, uNGAL, serum creatinine and GFR (inversely) and between uNGAL and, respectively, serum creatinine, proteinuria, albuminuria, serum albumin and GFR (both inversely). Conclusions: NGAL might play an important role in the pathophysiology of renal adaptation to diabetes, probably as a defensive mechanism aiming to mitigate tubular suffering. Furthermore, NGAL measurement might become a useful and noninvasive tool for the evaluation of renal involvement in diabetic patients as well as for the early diagnosis of incipient nephropathy. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

In developed countries, the incidence of end-stage renal failure is constantly increasing, and uremia will soon be a disease typically found in mature and elderly adults. Almost invariably, the physical condition of the elderly patient with terminal uremia is extremely poor, and therapeutic approach complex. Frequent co-morbidity, treatment with many different drugs, the high risk of iatrogenic damage, advanced age and socio-environmental conditions further complicate the management of these patients. While replacement therapy may become necessary, peritoneal dialysis may have advantages over hemodialysis. Peritoneal dialysis causes less hemodynamic stress, does not necessitate vascular access and allows mobility, although it incurs a high incidence of peritonitis and vascular disease. Where hemodialysis is the only feasible treatment, procedures used for vascular access are frequently followed by several complications, representing an important cause of morbidity and hospitalization. In addition, even if it may improve the patient’s quality of life, vascular condition, intradialytic hypotension, heart disease, intestinal bleeding and amyloidotic arthropathy are critical aspects of dialysis in the elderly patient. Therefore, particular attention from clinicians and administrators is required and the best possible strategies must be identified in order to provide effective and appropriate services to address these special patients’ needs. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Neutrophil gelatinase-associated lipocalin (NGAL) is a small 25-kDa protein released from kidney tubular cells after harmful stimuli. It represents one of the most promising future biomarkers in the diagnostic field of acute kidney injury (AKI), as the increase in NGAL levels is a good predictor of a brief-term onset of AKI, notably anticipating the resulting increase in serum creatinine. However, recent studies also suggest a possible role for NGAL in chronic kidney disease (CKD). For this reason we evaluated serum (sNGAL) and urinary NGAL (uNGAL) in a cohort of CKD patients in order to verify the relationship with the severity of renal impairment. In CKD patients sNGAL, uNGAL and the fractional excretion of this protein were notably increased as compared to controls. Furthermore both sNGAL and uNGAL were correlated with serum creatinine and, inversely, with residual glomerular filtration rate (GFR): this last relationship was found to be even closer than that found between GFR and serum creatinine. Multivariate models validate these correlations as independent, confirming that in these patients NGAL is a better predictor of GFR than serum creatinine. The results confirm NGAL as an important biomarker in clinical nephrology, extending to CKD the pathophysiological role of this protein in tubular adaptations to renal damage. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: Persistent proteinuria is a sign of renal damage caused by several factors, but it is itself a cause of tubular injury leading to chronic renal failure. Neutrophil gelatinase-associated lipocalin (NGAL) is a stress protein released by tubular cells which urinary excretion (uNGAL) increases in response to various stimuli. Methods: In the present study we analyzed uNGAL levels in 23 macroproteinuric patients with membranous glomerulonephritis. Results: In these subjects, uNGAL concentrations were significantly higher than in controls, directly correlated with proteinuria and inversely related to residual renal function. Patients were further categorized into two groups, according to a cut-off baseline uNGAL value of 350 ng/ml and evaluated during a 1-year follow-up period. After 12 months, subjects with higher uNGAL levels showed a significant worsening in baseline renal function and a 3.36 risk ratio of developing a severe decrease in GFR (≥50% of baseline values) compared with others. Conclusions: These findings suggest that NGAL may play a key role in tubular adaptations to persistent macroproteinuria. Furthermore, a new, interesting application of NGAL measurement could be proposed in clinical nephrology as a predictor of worsening renal function in patients affected by chronic kidney disease. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]