Body composition and ventricular function in hemodialysis patients.

There is no evidence about the potential role of body composition on cardiovascular mortality in dialysis patients. The aim of this study was to assess the relationship between body composition and changes in ventricular function. We conducted an observational study over a population of 78 patients on chronic hemodialysis. A transthoracic echocardiogram and a bioimpedance were performed at the beginning and at the end of the study. The mean follow-up time was 30.6 months. Patients who had a higher fat tissue index (FTI > 9.20 kg/m2 ) experienced a worsening in right and left ventricular function. They developed a greater fall in tricuspid annular plane systolic excursion (TAPSE) (-1 ± 4.3 mm) and left ventricular ejection fraction (LVEF)(-4.2 ± 6.8%), compared to those with lower FTI (p = 0.032 and p = 0.045, respectively). No associations were found between any other echocardiography or body composition parameters and overall mortality. Patients with right ventricular dysfunction (determined as TAPSE) experienced a tendency to higher mortality rate along the study (HR for mortality of 13.5 (95% CI, 1.1-166.7; p = 0.041)]. A higher fat tissue index could be associated with a deleterious effect over right and left ventricular function in dialysis patients.

Impact of Serum Magnesium Levels on Kidney and Cardiovascular Prognosis and Mortality in CKD Patients.

INTRODUCTION: In the general population, hypomagnesemia has been associated with cardiovascular events and hypermagnesemia with overall mortality. In chronic kidney disease (CKD) the evidence is not so strong. The objective of our study was to investigate the relationship between serum magnesium (SMg) concentration and cardiovascular morbidity and mortality, all-cause mortality, and the progression to kidney failure in a population with CKD. METHODS: Observational study of a cohort of 746 patients with CKD. Baseline characteristics and analytical profile were collected at the first visit, and patients were followed for a mean of 42.6 months. RESULTS: A cohort of 746 patients were analyzed, age 70 ± 13 years, 62.9% were male, 45.2% had CKD grade 3, and 35.9% grade 4. The mean SMg concentration was 2.09 ± 0.33 mg/dL, with a close correlation between SMg concentration and serum creatinine, phosphorus, and intact parathyroid hormone (iPTH) values. Use of calcitriol was associated with higher SMg (SMgH) concentration, while calcium supplements and proton pump inhibitors (PPIs) were associated with lower SMg concentration. For risk of cardiovascular events, patients with hypermagnesemia had an overall higher risk on a crude analysis (Log Rank 4.83, P = .28) and adjusted analysis (HR = 1.34, CI 1.02-1.77, P = .037). For risk of all-cause mortality, patients with hypermagnesemia had an overall higher risk on crude analysis (Log Rank 13.11, P > .001) and adjusted analysis (HR = 1.5424, IC = 1.002-2.319, P = .049). After performing a propensity score matching for SMg concentration, we achieved two comparable groups of 287 patients, finding again higher all-cause mortality in the hypermagnesemia group (LogRank 15.147, P < .001), that persisted in the Cox model adjusted for calcium, phosphorus, and iPTH. No association was found between SMg concentration and initiation of kidney replacement therapy (KRT). CONCLUSIONS: Magnesium concentration increases with decreasing kidney function. Hypermagnesemia predicts cardiovascular events and all-cause mortality in this same population. Thus, magnesium supplementation should be used with caution in these patients.

COVID-19: clinical course and outcomes of 36 hemodialysis patients in Spain.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia emerged in Wuhan, China in December 2019. Unfortunately, there is a lack of evidence about the optimal management of novel coronavirus disease 2019 (COVID-19), and even less is available in patients on maintenance hemodialysis therapy than in the general population. In this retrospective, observational, single-center study, we analyzed the clinical course and outcomes of all maintenance hemodialysis patients hospitalized with COVID-19 from March 12th to April 10th, 2020 as confirmed by real-time polymerase chain reaction. Baseline features, clinical course, laboratory data, and different therapies were compared between survivors and nonsurvivors to identify risk factors associated with mortality. Among the 36 patients, 11 (30.5%) died, and 7 were able to be discharged within the observation period. Clinical and radiological evolution during the first week of admission were predictive of mortality. Among the 36 patients, 18 had worsening of their clinical status, as defined by severe hypoxia with oxygen therapy requirements greater than 4 L/min and radiological worsening. Significantly, 11 of those 18 patients (61.1%) died. None of the classical cardiovascular risk factors in the general population were associated with higher mortality. Compared to survivors, nonsurvivors had significantly longer dialysis vintage, increased lactate dehydrogenase (490 U/l ± 120 U/l vs. 281 U/l ± 151 U/l, P = 0.008) and C-reactive protein levels (18.3 mg/dl ± 13.7 mg/dl vs. 8.1 mg/dl ± 8.1 mg/dl, P = 0.021), and a lower lymphocyte count (0.38 ×103/µl ± 0.14 ×103/µl vs. 0.76 ×103/µl ± 0.48 ×103/µl, P = 0.04) 1 week after clinical onset. Thus, the mortality among hospitalized hemodialysis patients diagnosed with COVID-19 is high. Certain laboratory tests can be used to predict a worsening clinical course.

Aspirin for Primary Prevention of Cardiovascular Disease and Renal Disease Progression in Chronic Kidney Disease Patients: a Multicenter Randomized Clinical Trial (AASER Study).

BACKGROUND: Patients with chronic kidney disease (CKD) are at high risk for developing cardiovascular events. However, limited evidence is available regarding the use of aspirin in CKD patients to decrease cardiovascular risk and to slow renal disease progression. STUDY DESIGN: Prospective, multicenter, open-label randomized controlled trial. SETTING AND PARTICIPANTS: One hundred eleven patients with estimated glomerular filtration rate (eGFR) 15-60 ml/min/1.73 m2 without previous cardiovascular events. INTERVENTION: Aspirin treatment (100 mg/day) (n = 50) or usual therapy (n = 61). Mean follow-up time was 64.8 ± 16.4 months. OUTCOMES: The primary endpoint was composed of cardiovascular death, acute coronary syndrome (nonfatal MI, coronary revascularization, or unstable angina pectoris), cerebrovascular disease, heart failure, or nonfatal peripheral arterial disease. Secondary endpoints were fatal and nonfatal coronary events, renal events (defined as doubling of serum creatinine, ≥ 50% decrease in eGFR, or renal replacement therapy), and bleeding episodes. RESULTS: During follow-up, 17 and 5 participants suffered from a primary endpoint in the control and aspirin groups, respectively. Aspirin did not significantly reduce primary composite endpoint (HR, 0.396 (0.146-1.076), p = 0.069. Eight patients suffered from a fatal or nonfatal coronary event in the control group compared to no patients in the aspirin group. Aspirin significantly reduced the risk of coronary events (log-rank, 5.997; p = 0.014). Seventeen patients in the control group reached the renal outcome in comparison with 3 patients in the aspirin group. Aspirin treatment decreased renal disease progression in a model adjusted for age, baseline kidney function, and diabetes mellitus (HR, 0.272; 95% CI, 0.077-0.955; p = 0.043) but did not when adjusted for albuminuria. No differences were found in minor bleeding episodes between groups and no major bleeding was registered. LIMITATIONS: Small sample size and open-label trial. CONCLUSIONS: Long-term treatment with low-dose aspirin did not reduce the composite primary endpoint; however, there were reductions in secondary endpoints with fewer coronary events and renal outcomes. ClinicalTrials.gov Identifier: NCT01709994.

Universal Sustained Viral Response to the Combination of Ombitasvir/Paritaprevir/Ritonavir and Dasabuvir with/without Ribavirin in Patients on Hemodialysis Infected with Hepatitis C Virus Genotypes 1 and 4.

BACKGROUND: Hepatitis C virus (HCV) infection is highly prevalent among patients on hemodialysis (HD) and is associated with poor prognosis. Treatment with interferon and ribavirin is poorly tolerated, and few data are available on the impact of new direct-acting antivirals (DAAs). This study was intended to analyze the efficacy and safety of treatment with a combination of ombitasvir/paritaprevir/ritonavir and dasabuvir with/without ribavirin in HCV-infected patients on HD from 3 hospitals. METHODS: This is a multicentric study. We analyze the clinical course of all patients on HD with HCV infection who had been treated with the combination of ombitasvir/paritaprevir/ritonavir and dasabuvir in 3 hospitals in Madrid, Spain. All patients under treatment had undergone Transient elastography (FibroScan®) and HCV RNA (PCR) and HCV genotype were determined simultaneously. RESULTS: Thirty-five patients aged 53.3 ± 8.9 years (68.6% males) and with genotypes 1 and 4 were treated with the DAA regimen, and 17 were also given ribavirin. The most common etiology was glomerular disease. Sustained viral response was achieved in 100% of patients. Adverse effects were negligible, and no patient had to discontinue treatment. The most significant side effect was anemia, which led to a significant increase in the dose of erythropoiesis-stimulating agents. Anemia was more marked in patients receiving ribavirin. No patients required transfusions. CONCLUSION: A combination of ombitasvir/paritaprevir/ritonavir and dasabuvir with/without ribavirin for the treatment of HCV in patients on HD is highly effective and causes minimal side effects. This regimen represents a major advance in disease management. A considerable improvement in prognosis seems likely.

Pulmonary Hypertension Is Associated with Mortality and Cardiovascular Events in Chronic Kidney Disease Patients.

BACKGROUND: We evaluated the prevalence, determinants and prognosis value of pulmonary hypertension (PH) in non-dialysis chronic kidney disease (CKD) patients. METHODS: This is a prospective study with stages 3-5 non-dialysis-dependent CKD patients. PH was estimated by Doppler echocardiography and defined as a pulmonary artery systolic pressure above 35 mm Hg. RESULTS: Three hundred fifty-three patients were recruited, of whom 94 (26.6%) had PH. Prevalence of PH increased with the decline of renal function: 21.6, 24.1, and 31.7% in stages 3, 4, and 5, respectively. Independent predictors of PH were age, estimated glomerular filtration rate (eGFR), history of cardiovascular (CV) events, the presence of an arteriovenous fistulae (AVF), and left ventricular (systolic and diastolic) dysfunction. Over a median follow-up of 22 months, 71 patients died (20%). After multivariate adjustment for age, gender, previous CV disease, diastolic and systolic dysfunction, PH remained as an independent predictor of all-cause mortality (hazards ratio [HR] 1.84, 95% CI 1.06-3.18, p = 0.02). One hundred patients (28%) had a new onset CV event. After adjustment for age, gender, previous CV disease, systolic and diastolic dysfunction, PH maintains its independent association with CV events (HR 2.77, 95% CI 2.00-3.25, p < 0.001). CONCLUSIONS: PH prevalence rises as kidney function declines. Main determinants of PH are age, eGFR, previous CV disease, the presence of an AVF and left ventricular systolic or diastolic dysfunction. PH is an independent predictor of all-cause mortality and CV events.

Pulmonary hypertension is an independent predictor of cardiovascular events and mortality in haemodialysis patients.

AIM: The evidence about prevalence, associated factors of pulmonary hypertension (PH) and its impact on patient's outcomes is limited. METHODS: We included 211 haemodialysis patients, we estimated the systolic pulmonary artery pressure (SPAP) by 2D Doppler echocardiography defining PH as a SPAP above 35 mmHg, the median follow-up was 39 (19-56) moths, and the primary endpoints were all cause mortality and cardiovascular events. RESULTS: We found PH in 91 patients (43.9%). Independent determinants of PH were age, previous cardiovascular disease, the Nt-pro-BNP level hs-TnT, the systolic dysfunction, diastolic dysfunction and left ventricular hypertrophy. Over the follow-up 94 cardiovascular events occurred, variables associated were: PH, age, history cardiovascular disease, dyslipidaemia, elevated concentration of Nt-pro-BNP and hs-TnT, systolic and diastolic dysfunction, in a multivariate model, the PH maintained its independent association. Mortality data: 88 patients died (41.7%); 35 (29.5%) in the no PH group and 53 (58.5%) in the PH group (P < 0.001). In the Cox survival analysis, we found an association between mortality and age, previous cardiovascular disease, history of peripheral vascular disease, Nt-pro-BNP levels. In a multivariate model the PH remains as independent predictor of mortality. CONCLUSIONS: Pulmonary hypertension is a common finding in HD patients and a valuable predictor of mortality and cardiovascular events. Prospective studies are needed to assess the effect of intervention on risk factors in improving patient's outcomes.

Body Composition Affects Urea Distribution Volume Estimated by Watson's Formula.

OBJECTIVE: Dialysis machines use the Watson formula (Vwatson) to estimate the urea distribution volume (UDV) to calculate the online Kt/V for each dialysis session. However, the equation could give rise to inaccuracies. The present study analyzes whether body composition affects UDV estimated by Vwatson in comparison to bioimpedance spectroscopy (Vbis) as the reference method. DESIGN: This is a transversal study performed in the setting of a hemodialysis unit. SUBJECTS: Prevalent hemodialysis patients. INTERVENTION: The same day, UDV was measured using Vwatson and Vbis. We compared their results. MAIN OUTCOME MEASURE: Differences between UDV using Watson equation and Vbis. RESULTS: We included 144 prevalent patients. Vwatson overestimated the volume with regard to Vbis (Vwatson - Vbis) by 2.5 L (1.8 L; P = .001). We found an excellent correlation between the 2 methods. A higher mean Vwatson - Vbis value was correlated to older age (P = .03), body mass index (P = .01), fat tissue index (P = .001), lower lean tissue index (P = .001), lower extracellular water (P = .01), and intracellular water (P = .001). CONCLUSION: Body composition affects UDV estimated by Vwatson, thus modifying the result of Kt/V. In young patients who present more lean tissue and less fat tissue, Kt/V is underestimated with Vwatson.

Body composition affects the response to erythropoiesis-stimulating agents in patients with chronic kidney disease in dialysis.

BACKGROUND: The response to erythropoiesis-stimulating agents (ESA) in patients with chronic kidney disease (CKD) is variable. The body mass index (BMI) variations can modify the response to ESA. The objective was to assess the effect of body composition on the response to ESA in dialysis patients. METHODS: This is an observational cross-sectional study. Prevalent hemodialysis and peritoneal dialysis (PD) patients were selected. In the same day, a single blood test, a body composition analysis using bioimpedance spectroscopy and anthropometric measurements were performed. We collected ESA doses. We analyzed erythropoietin resistance index (ERI). The ERI was calculated dividing the weekly weight-adjusted (kg) dose of ESA (IU) by the hemoglobin level (g/dL). RESULTS: The study was comprised of 218 patients (58% men; age 65 (16) years old; 80% hemodialysis, 20% PD). There was an inverse correlation between ERI and BMI (p=0.01), fat tissue index (FTI) (p=0.01) and prealbumin (p=0.04). We found an independent association between higher ERI levels and lower FTI and prealbumin values. CONCLUSION: Response to ESA is influenced by body composition. Fat tissue favors the body's response to ESA.

Detection of patients at high risk for non-occlusive mesenteric ischemia in hemodialysis.

BACKGROUND: Nonocclusive mesenteric ischemia (NOMI) is an emerging condition in hemodialysis (HD) patients not widely studied. MATERIALS AND METHODS: A retrospective study was conducted between 2003 and 2011. NOMI cases were recorded, and demographic, clinical, biochemical, and HD parameters were collected. This group was compared with a control group (n = 93). Risk factors, prognosis, and survival were analyzed. RESULTS: There were 57 episodes of NOMI (incidence, 2.29 episodes per 100 patients/y). Cecum was the most frequently affected segment. Nineteen patients (33%) underwent surgery. Twenty-six patients (59%) did not survive the acute episode. Cecal damage was the only protective factor associated with mortality (relative risk [RR], 0.712; P = 0.044). The incidence of NOMI was related to erythropoietin resistance index, diabetes mellitus, and longer time on HD compared with control group (RR, 6.92, P = 0.009; RR, 9.98, P = 0.005; and RR, 1.017, P < 0.001, respectively). Mortality in survival NOMI patients was higher at 4-y follow-up compared with that in the control group (log-rank, 15.5; P < 0.0001). CONCLUSIONS: NOMI is associated with erythropoietin resistance index, diabetes mellitus, and longer time on HD. Hypotension must be avoided in these high-risk patients to prevent NOMI.

Diastolic dysfunction and high levels of new cardiac biomarkers as risk factors for cardiovascular events and mortality in hemodialysis patients.

BACKGROUND/AIMS: Cardiovascular events (CVEs) are the most frequent cause of death in hemodialysis (HD). We aim to determine cardiovascular and mortality risk factors. METHODS: A historical cohort study was made of 211 prevalent HD patients [73 (60-80) years, 58% males] between 2005 and 2012. Demographic, laboratory test and echocardiographic values were recorded. During follow-up, CVEs and mortality were documented and analyzed. RESULTS: 94 patients suffered a CVE. Age, history of cardiovascular disease (CVD), peripheral vascular disease, cardiac markers, systolic and diastolic dysfunction (DD) were associated to CVEs. Low albumin (RR 0.414, p = 0.002), DD (1.876, p = 0.038) and previous CVD (3.723, p < 0.001) were identified as independent predictors of CVEs. 98 patients died. Age, a history of CVD, peripheral vascular disease, cardiac markers, DD, dialysis vintage, and a vascular access different from autologous fistulae were associated to mortality. Low albumin (RR 0.499, p = 0.046), DD (RR 2.414, p = 0.017) and a vascular access different from autologous fistulae (RR 2.058, p = 0.034) were independent predictors of mortality. CONCLUSIONS: DD is an emergent risk factor for death and CVEs in dialysis. Low albumin is also a predictor for CVE. Non-autologous fistulae and low albumin are predictors for death. Nt-proBNP and hsTnT offer good information for identifying high-risk patients, but they do not predict events independently as they are only cardiac damage markers.

Impact of preoperative exercise in not initially candidates to native arteriovenous fistulas.

BACKGROUND: Native autologous arteriovenous fistula (AVFn) is the preferred vascular access for hemodialysis due to its long term patency and low complication rate. A challenging limitation is the anatomical inability to perform AVFn and failure of maturation. Preoperative isometric exercise (PIE) can increase vascular calibers and improve the rate of distal AVF. However, it is unknown whether PIE might enhance the performance of AVFn in patients who are not initially candidates. METHODS: A retrospective observational study was conducted over a population of 45 patients evaluated in vascular access clinic, 23 were not initially candidates for radiocephalic (NRC-AVF) and 22 were not candidates for autologous fistula at all (NA-AVF). They were assigned to perform PIE with handgrip device and revaluated. RESULTS: After 4-8 weeks of PIE, a AVFn was performed in 16 patients from NA-AVF group and a radiocephalic AVFn was performed in 21 patients from NRC-AVF group. Both groups experienced a significant and similar increase in venous caliber 0.91 ± 0.43 mm in NA-AVF versus 0.76 ± 0.47 mm in NRC-AVF (p = 0.336) and arterial caliber 0.18 ± 0.24 mm versus 0.18 ± 0.21 mm (p = 0.928), respectively. Nevertheless, primary failure rate was significantly higher in NA-AVF (n = 8, 50%) than in NRC-AVF group (n = 3, 14.3%) (p = 0.030). After 6 months, the fistula usability for dialysis was only 50% in NA-AVF, while 86.7% were dialyzed by fistula in NRC-AVF group (p = 0.038). CONCLUSIONS: PIE allowed the allocation of an AVFn in patients not initially candidates, but entailed a high rate of maturation failure. Patients not candidates to radiocephalic AVF benefited from PIE and preserved a long term usability of AVF for dialysis.

Expanded hemodialysis: Is anticoagulation of the dialysis circuit different from online hemodiafiltration and high-flux hemodialysis?

Expanded hemodialysis (HDx) has a high capacity for removing medium and medium-large molecules; however, there are no specific recommendations during HDx for anticoagulation of the dialysis circuit. We aimed to evaluate the differences in the efficacy of anticoagulation procedures using the venous port and 40 mg enoxaparin in HDx compared to high-flux hemodialysis (HF-HD) and postdilution online hemodiafiltration (HDF). We compared anticoagulant activity in 11 patients in HDx, HF-HD, and HDF under similar dialysis conditions. In the 33 dialysis sessions, 40 mg enoxaparin was administered through the venous port, and pre- and postdialysis antifactor Xa activity (aXa) and activated partial thromboplastin time (APTT), postdialysis clotting time of the vascular access, visual clotting score of the dialyzer, and any complications with the extracorporeal circuit or bleeding were registered. APTT postdialysis in HDx was not significantly different from that in HF-HD and HDF. Postdialysis aXa in HDx was not significantly different from that in HF-HD and HDF. We found no significant differences in visual clotting score of the dialyzer. Enoxaparin administered through the venous port was sufficient for anticoagulation within the extracorporeal circuit in HDx, HF-HD, and HDF. There were no differences in postdialysis aXa or APTT, most likely because when low molecular-weight heparin is applied through venous port, lesser enoxaparin concentration reaches the dialyzer. Thus, we conclude that the dose of enoxaparin administered through the venous port should not be adjusted according to dialysis technique.

Factors related to the absence of anemia in hemodialysis patients.

BACKGROUND: A small number of hemodialysis (HD) patients have normal hemoglobin (Hb) levels without the need for erythropoiesis-stimulating agents (ESAs). The factors associated with this condition have been little studied. The objective of this prospective study was to determine these factors in a prevalent population of HD patients. MATERIALS AND METHODS: All patients who had normal Hb levels and who had not received ESAs in the last 6 months (non-ESA group) were included. Epidemiological and laboratory data were collected and we performed an abdominal ultrasound to assess hepatic and renal cysts. This group was compared to a control group of 205 prevalent HD patients on ESA therapy (control group). RESULTS: We included 45 patients (16% from the whole group) in the non-ESA group. In this group, there was a higher proportion of men (76.5 vs. 61%), patients were younger (61.1 ± 14.7 vs. 67.5 ± 15.2 years), had a longer duration of renal replacement therapy (RRT) (9.4 ± 8.3 vs. 5.3 ± 5.8 years) and had a higher prevalence of adult polycystic kidney disease (APKD) and hepatitis C virus (HCV) liver disease (42.2 vs. 10.2%), p < 0.01. In the non-ESA group, HCV+ patients had a lower prevalence of APKD (2.2 vs. 38.4%) and hepatic cysts (2.2 vs. 19.2%), but significantly higher endogenous erythropoietin levels (55.8 ± 37.1 vs. 30.9 ± 38.4 mU/ml). No significant differences in anemia, iron metabolism, insulin, IGF-1 and renin were found between non-ESA and control groups. Non-ESA patients had a significantly higher number of renal (90.6 vs. 36.5%) and hepatic cysts (12.5 vs. 3.4%), and these were also larger in size (3.3 ± 2.4 vs. 1.5 ± 0.8 cm). In the multivariate Cox analysis, independent predictor factors for absence of anemia in HD patients were number of renal cysts >10 cysts (95% CI 1.058-1.405; p = 0.00), HCV+ liver disease (95% CI 1.147-1.511; p = 0.05) and time on RRT (95% CI 1.002-1.121; p = 0.05). CONCLUSIONS: The absence of anemia in HD patients is not infrequent. Its frequency is higher in men and younger patients with long-term RRT, in patients with HCV+ liver disease and in APKD. It is associated with increased endogenous erythropoietin production and the presence of renal and hepatic cysts.

Efficacy of enoxaparin in preventing coagulation during high-flux haemodialysis, expanded haemodialysis and haemodiafiltration.

BACKGROUND: Low-molecular-weight heparins (LMWHs) are easily dialysable with high-flow membranes; however, it is not clear whether the LMWH dose should be adjusted according to the membrane type and dialysis technique. This study aimed to evaluate the influence of the dialyser on anticoagulation of the extracorporeal dialysis circuit. METHODS: Thirteen patients received the same dose of LMWH through the arterial port via three dialysis techniques: high-flux haemodialysis (HF-HD), online haemodiafiltration (HDF) and expanded haemodialysis (HDx). All dialysis was performed under similar conditions: duration, 4 h; blood flow, 400 mL/min; and dialysate flow, 500 mL/min. Antifactor Xa (aXa) activity and activated partial thromboplastin time (APTT) were measured before and after the dialysis. Clotting time of the vascular access site after haemodialysis, visual clotting score of the dialyser and any complications with the extracorporeal circuit or bleeding were registered. RESULTS: Post-dialysis aXa activity in HF-HD (0.26 ± 0.02 U/mL) was significantly different from that in HDF (0.21 ± 0.02 U/mL, P = 0.024), and there was a trend in HDx (0.22 ± 0.01 U/mL, P = 0.05). APTT post-dialysis in HF-HD (30.5 ± 0.7 s) was significantly different from that in HDx (28.2 ± 0.64 s, P = 0.009) and HDF (28.8 ± 0.73 s, P = 0.009). CONCLUSIONS: AXa activity in HDF was significantly lower than that in HF-HD, possibly because of more losses of LMWH through the dialyser. Given the higher anticoagulant loss in HDF and probably in HDx than in HF-HD, the enoxaparin dose administered may be adjusted according to the dialysis technique.

Intradialytic hypotension and relationship with cognitive function and brain morphometry.

BACKGROUND: The haemodynamic stress brought about by dialysis could justify the loss of structural and functional integrity of the central nervous system (CNS). The main objective of this study was to analyse the relationship between intradialytic hypotension (IDH) and cognitive function and brain morphometry. METHODS: The cross-sectional KIDBRAIN study (Cohort Study of Morphological Changes of the Brain by MRI in Chronic Kidney Disease Patients) included 68 prevalent patients with no history of neurological disorders (cerebrovascular disease and cognitive impairment) undergoing haemodialysis (HD). We analysed 18 non-consecutive dialysis sessions (first three of each month over a 6-month period) and various definitions of IDH were recorded. Global cognitive function (GCF) was assessed using the Mini-Mental State Examination (MMSE) and parameters of structural integrity of the CNS were obtained using volume morphometry magnetic resonance imaging analysis [grey matter (GM), white matter (WM) and hippocampus). RESULTS: A greater number of sessions with IDH were associated with less volume of WM (r = -0.359,P = 0.003) and hippocampus (r = -0.395, P = 0.001) independent of cardiovascular risk factors according to multivariable linear regression models (ß = -0.198, P = 0.046 for WM; ß = -0.253, P = 0.017 for hippocampus). The GCF by the MMSE was 27.3 ± 7.3.1 and was associated with WM volume (ß = 0.403, P = 0.001) independent of GM and hippocampus volume. Symptomatic IDH was associated with GCF (r = -0.420, P < 0.001) in adjusted analysis (ß = -0.339, P = 0.008). CONCLUSIONS: Even when asymptomatic, IDH is associated with a lower WM and hippocampus volume and reduced GCF in patients undergoing HD, thus suggesting greater vulnerability of the brain to the haemodynamic stress that may be generated by a dialysis session.

Intradialytic hypotension definitions with mortality prediction capacity in a cohort of haemodialysis patients. / Definiciones de hipotensión intradiálisis con poder predictivo de mortalidad en una cohorte de hemodiálisis.

INTRODUCTION: Intradialytic hypotension (IDH) is a common complication and is associated with higher morbidity and mortality in patients on haemodialysis. However, there is a lack of uniformity in definitions of IDH. The main objective of this study is to analyse clinical and dialysis related factors with several IDH definitions, and its relationship with morbidity and mortality in a cohort of haemodialysis patients. METHODOLOGY: Observational study with a 30-month follow-up period that includes 68 prevalent patients on haemodialysis with at least six months of treatment. We analysed 18 non-consecutive dialysis sessions (first three of each month of a six-month period), and different definitions of IDH were recorded. A positive event of IDH was defined if any definition occurred in more than 25% of the sessions studied. Using survival analysis, we analysed the prediction capacity of each IDH definition (Nadir90, Nadir100, Fall20, Fall30, Fall20Nadir90, Fall30Nadir90, KDOQI, HEMO). The relationship with non-fatal cardiovascular disease and global mortality was estimated using different Cox proportional models. RESULTS: We found IDH definitions that occurred significantly more frequently (Nadir100: 339.8/1,000 sessions, Nadir90: 172.3/1,000 sessions) than others (KDOQI: 98/1,000 sessions, HEMO 129.9/1,000 sessions). We registered 13 fatal events with a mean follow-up of 27.12±6.84 months. A greater number of sessions with IDH according to the Nadir90 definition was a predictive factor of mortality (Log rank 5.02, p=0.025), independent according to adjusted models (HR: 3.23 [95% CI: 1.08-9.6], p=0.035). The definitions Nadir100 (HR: 4.54 [95% CI: 1.25-16.4], p=0.02) and Fall30Nadir90 (HR: 3.08 [95% CI: 1.07-8.8], p=0.03) were independent predictors of non-fatal cardiovascular disease in adjusted models. CONCLUSIONS: Intradialytic hypotension, even asymptomatic, is a predictor of mortality and non-fatal cardiovascular disease in prevalent patients on haemodialysis.

The new marker YKL-40, a molecule related to inflammation, is associated with cardiovascular events in stable haemodialysis patients.

BACKGROUND: YKL-40 is a glycoprotein associated with inflammatory conditions, including atherosclerosis and endothelial dysfunction. The objective was to analyse serum YKL-40 levels in a haemodialysis population and explore their association with dialysis dosing measures, inflammation, body composition and development of cardiovascular (CV) events. METHODS: We performed a prospective study of 78 chronic haemodialysis patients enrolled in 2013 and followed up until 2018. At baseline, serum YKL-40, inflammatory and nutrition markers and body composition were assessed. During a median follow-up of 43 (interquartile range 24-66) months, CV events were recorded. RESULTS: The mean age of patients was 62 ± 16 years and 66% were men. The mean YKL-40 was 207 ± 106 ng/dL. Higher YKL-40 levels were associated with lower Kt/V urea, convective volume, serum albumin and prealbumin and with higher troponin T. During follow-up, 50% developed CV events. Cox analysis showed an association between CV events and YKL-40, diabetes, hypertension, C-reactive protein, lower prealbumin, ß2-microglobulin, glycosylated haemoglobin and troponin T values. The multivariate Cox analysis confirmed an independent association between CV events and YKL-40 {hazard ratio [HR] 1.067 [95% confidence interval (CI) 1.009-1.211]; P: 0.042}, troponin T [HR 1.037 (95% CI 1.009-1.683); P: 0.007], lower prealbumin [HR 0.827 (95% CI 0.224-0.988); P: 0.009] and diabetes [HR 2.103 (95% CI 1.554-3.172); P: 0.008]. Kaplan-Meier confirmed the association between CV events and YKL-40 (log rank 7.28; P = 0.007). CONCLUSIONS: YKL-40 is associated with CV events in haemodialysis patients. Higher dialysis dose and convective volume are associated with lower serum YKL-40 levels.

Exercise training during hemodialysis sessions: Physical and biochemical benefits.

Chronic inflammation, protein-energy wasting, and poor physical functioning are highly prevalent among patients with chronic kidney disease (CKD). These factors are associated with disability and increase of cardiovascular risk. The aim of this study is to evaluate the effects of exercise training during hemodialysis (HD) sessions on physical functioning, body composition, and nutritional and inflammatory status. We performed a prospective intervention study including patients on prevalent HD therapy. Patients were evaluated at baseline visit by Rehabilitation and Physiotherapy specialists and the exercise program was adapted to each patient's physical capacity. In addition to demographic, clinical, body composition and functional ability data, serum markers regarding nutritional and inflammatory status were collected at baseline and after 3 months of exercise training. We observed a significant improvement after 3-month follow-up in functional ability (6 minute walk test [6MWT] [403.15 ± 105.4 vs 431.81 ± 115.5 m, P < .001], sit-to-stand repetitions in 30 seconds [12.2 ± 4.2 vs 14.1 ± 5.0 repetitions, P = .003] and dynamometry [24.5 ± 11.9 vs 29.5 ± 12.5 kg, P < 0.001]), body composition with increase of body mass index (BMI) (23.7 ± 4.4 vs 24.1 ± 4.7 kg/m2 , P = 0.01) at the expense of lean tissue index (LTI) (14.9 ± 3.7 vs 16.2 ± 2.9 kg/m2 , P = 0.038) and lipid parameters with LDL-cholesterol decrease (70.2 ± 17.9 vs 64.9 ± 21.3 mg/dL, P = .03) and lower serum triglyceride levels (125.8 ± 54.0 vs 108.2 ± 44.6 mg/dL, P = .006). In addition, we found a decrease in iron (155.6 ± 148.2 vs 116.7 ± 110.8 mg, P = .029) and erythropoietin (117.5 ± 84.2 vs 99.2 ± 74.5 µg, P = .023) requirements. The implementation of exercise training programs during HD can improve physical functioning, body composition and lipid and anemia profile. Supervised exercise programs could be included as part of HD patient care to improve physical capacity in these patients.

Influence of calcium concentration in haemodialysis fluid on blood pressure control. / Influencia de la concentración de calcio en el líquido de hemodiálisis sobre el control de la tensión arterial.

BACKGROUND: Hypertension is a highly prevalent disorder among patients undergoing haemodialysis. It contributes to greater cardiovascular risk and must be controlled. However, despite dietary measures, haemodialysis regimen optimisation and pharmacological treatment, some patients in our units continue to maintain high blood pressure levels. The objective of the study is to demonstrate that reducing calcium in dialysis fluid can help treat hypertension patients undergoing haemodialysis. MATERIAL AND METHODS: We selected all of the hypertensive patients from our haemodialysis unit. We checked their normovolemic status by means of bioimpedance spectroscopy, decreasing the haemodialysis fluid's calcium concentration to 2.5mEq/l, with a follow-up period of 12 months. RESULTS: A total of 24 patients met the non-volume dependent hypertension criteria (age 61±15 years, males 48%, diabetes 43%). A significant systolic and diastolic blood pressure decrease was observed at 6 and 12 months as a result of reducing the dialysis calcium concentration; this was not accompanied by greater haemodynamic instability (baseline systolic blood pressure: 162±14 mmHg; at 6 months: 146±18 mmHg; at 12 months: 141±21 mmHg; P=.001) (baseline diastolic blood pressure: 76±14 mmHg; at 6 months: 70±12 mmHg; at 12 months: 65±11 mmHg; P=.005). A non-significant increase in plasma parathyroid hormone levels was also found. No side effects were observed. CONCLUSIONS: Adding 2.5mEq/l of calcium to dialysis fluid is a safe and effective therapeutic alternative to control hard-to-manage hypertension among haemodialysis patients.