María-de-Jesús Ventura

NT-proBNP, fluid volume overload and dialysis modality are independent predictors of mortality in ESRD patients

BACKGROUND N-terminal fragment of B-type natriuretic peptide (NT-proBNP) is a marker of both fluid volume overload and myocardial damage, and it has been useful as a predictor of mortality in patients with end-stage renal disease (ESRD). It has been suggested that continuous ambulatory peritoneal dialysis (CAPD), automated peritoneal dialysis (APD) and haemodialysis (HD) may have different effects on fluid volume and blood pressure control; however, whether the independent predictive value of NT-proBNP for mortality is preserved when analysed in conjunction with fluid overload and dialysis modality is not clear. METHODS A prospective multicentre cohort of 753 prevalent adult patients on CAPD, APD and HD was followed up for 16 months. Plasmatic levels of NT-proBNP, extracellular fluid volume/total body water ratio (ECFv/TBW) and traditional clinical and biochemical markers for cardiovascular damage risk were measured, and their role as predictors of all-cause and cardiovascular mortality was analysed. RESULTS NT-proBNP level, ECFv/TBW and other cardiovascular damage risk factors were not evenly distributed among the different dialysis modalities. NT-proBNP levels and ECFv/TBW were correlated with several inflammation, malnutrition and myocardial damage markers. Multivariate analysis showed that NT-proBNP levels and ECFv/TBW were predictors of both all-cause and cardiovascular mortality, independently of dialysis modality and the presence of other known clinical and biochemical risk factors. CONCLUSIONS NT-proBNP is a reliable predictor of death risk independently of the effect of dialysis modality on fluid volume control, and the presence of other clinical and biochemical markers recognized as risk factors for all-cause and cardiovascular mortality. NT-pro-BNP is a good predictor of mortality independently of fluid volume overload and dialysis modality.

Echocardiographic, electrocardiographic and blood pressure changes induced by icodextrin solution in diabetic patients on peritoneal dialysis

The use of icodextrin as an osmotic agent in solutions for peritoneal dialysis (PD) has important cardiovascular effects related with better control of extracellular volume. Among them, reduction of arterial pressure and an improvement in echocardiographic parameters stand out. In diabetic patients, icodextrin has additional potential advantages related with better metabolic control. In a multicenter, open-label randomized controlled trial, the effects of icodextrin solutions were compared to glucose solutions on echocardiographic, electrocardiographic, and blood pressure changes in diabetic patients on PD. Two phases were noted in the follow-up. In the early phase (6 months), reduction in ambulatory blood pressure (ABP) and left ventricular end diastolic diameter were found in the icodextrin group. These changes correlated with changes in body fluids. In the late phase (12 months), a trend towards baseline values in ABP was seen. Changes in inferior vena cava diameter and in low frequency R-R variability spectral analysis in the icodextrin group suggest that icodextrin increases circulating blood volume and sympathetic tone, probably by accumulation of icodextrin metabolites in the bloodstream and improvement in diabetic neuropathy as a result of lower peritoneal glucose absorption. The effects of icodextrin in diabetic patients were related to better fluid management and metabolic control.

Vitamin D receptor gene, biochemical bone markers and bone mineral density in Mexican women on dialysis

BACKGROUND The influence of the Bsm1 polymorphism of the vitamin D receptor (VDR) gene on mineral and bone disorders in chronic kidney disease (CKD) is still under discussion. The aim of this study was to analyse the relationship between VDR polymorphism, bone mineral density (BMD), biochemical bone markers and clinical factors in women on peritoneal dialysis (PD) and haemodialysis (HD). METHODS In a cross-sectional study, 197 women (42 +/- 10 years; 25% with diabetes mellitus (DM); body mass index (BMI) 25.26 +/- 4.77 kg/m(2)) treated by PD (72%) or HD (28%) underwent measurements of BMD (measured at the calcaneus by quantitative ultrasound; expressed as T- and Z-scores) and plasma total calcium (tCa), intact parathyroid hormone 1-84 (iPTH), phosphorus, albumin, glucose, osteoprotegerin (OPG), fetuin-A, intact osteocalcin-49 and N-MID fragment 1-43 aa (N-MID osteocalcin) N-terminal propeptide of type 1 procollagen (PINP) and C-terminal telopeptide-beta aspartic acid (BCL). DNA was extracted from peripheral blood. PCR products were digested with Bsm1 to analyse VDR polymorphism. RESULTS The Z-score of BMD was -1.1 +/- 1.03. According to the values of osteopenia (T-score = -1.0), patients with higher BMD were younger, had lower frequency of amenorrhoea and diabetes and had higher serum creatinine and fetuin levels as well as lower levels of PINP. In a stepwise multivariate logistics analysis, osteopenia was associated with presence of genotype BB+Bb (OR = 3.26, P < or = 0.003) and age (OR = 0.95, P = 0.050). According to the B allele, bb: n = 126 (64%) and BB+Bb: n = 71(36%), group bb had significantly higher mean Z-scores (-0.97 +/- 1.0 vs -1.3+/-0.92; P < or = 0.021). CONCLUSIONS The high frequency of osteopenia observed in female CKD patients on dialysis is associated with age and genetic predisposition as revealed by its association to the Bsm1 VDR polymorphism.

Reaching Targets for Mineral Metabolism Clinical Practice Guidelines and Its Impact on Outcomes Among Mexican Chronic Dialysis Patients

BACKGROUND AND AIMS An increasing number of studies have been published concerning meeting targets of clinical guidelines for different aspects of the diagnosis and treatment of patients with end-stage renal disease. Most of these studies have shown that guideline recommendations are not always satisfied, and results outside target limits have been associated with high rates of mortality and morbidity. The objective of this study was to analyze the frequency of reaching mineral and bone metabolism-related guideline targets and its impact on clinical outcomes in Mexican chronic dialysis patients. METHODS A cohort of prevalent peritoneal dialysis (PD) and hemodialysis (HD) patients were analyzed at baseline and followed for at least 16 months. Patients were on continuous ambulatory peritoneal dialysis (CAPD), automated peritoneal dialysis (APD), and HD and contracted HD modalities where patients received HD sessions outside institution facilities. RESULTS We studied 753 patients. The percentage of patients within target limits for phosphorus was 35%, for calcium 32%, and for PTH 12%. The most frequent pattern was hyperphosphatamia, hypercalcemia, and low PTH. This was even more frequent in CAPD patients, probably due to the high percentage of diabetic patients. Hypercalcemia was found as an independent risk factor for mortality. CONCLUSIONS The most important results suggest that guideline recommendations are not usually satisfied and that hypercalcemia, in addition to other traditional risk factors, is associated with high mortality rates. The study also detected some opportunities to improve the quality of treatment by reducing the calcium content of dialysis solutions and reducing the use of calcium carbonate as a phosphate binder.

La disminución de triyodotironina se asocia con la elevación del péptido natriurético cerebral N-terminal y con la mortalidad en pacientes en diálisis

BACKGROUND Low thyroid hormone (TH) levels and myocardial damage are common in dialysis patients and are associated with mortality. However, little is known about the role of THs on myocardial damage as has been described in primary thyroid diseases. The aim of this study was to explore the potential relationship between low total triiodothyronine (total T3) and biomarkers of myocardial damage and the effect of their interaction on mortality, to ascertain if cardiovascular damage is the link between low THs and the risk of death in dialysis patients with CKD. MATERIAL AND METHODS TH plasma levels, nutritional markers, inflammation and myocardial damage were studied in 296 patients undergoing peritoneal dialysis or haemodialysis, who were followed up for 16 months to ascertain the association between biochemical variables and mortality. RESULTS Low total T3 levels were found in 45% of patients, which was inversely correlated with C-reactive protein (CRP) and NT-proBNP, and directly correlated with albumin and transferrin. Diabetes, CRP and total T3 were risk factors for all-cause mortality, and CRP, NT-proBNP and total T3 for cardiovascular mortality. CONCLUSIONS Low total T3 levels are common in dialysis patients and are associated with inflammation, malnutrition and myocardial damage. The latter may be the link between low THs and all-cause and cardiovascular mortality.