Tubular biomarkers and histology in lupus nephritis.

INTRODUCTION: The relevance of tubulo-interstitial involvement for kidney prognosis has recently been emphasized, but validated biomarkers for predicting histology are still lacking. The aim of our study was to evaluate different serum and urinary markers of tubular damage in patients with lupus nephritis (LN) and to correlate them with kidney histopathology. METHODS: A single-center retrospective study was conducted from January 2016 to December 2021. Serum and urine samples were collected on the same day of kidney biopsy and correlated with histologic data from a cohort of 15 LN patients. We analyzed the following urinary markers, adjusted for urine creatinine: beta 2-microglobulin, alpha 1-microglobulin, NGAL, uKIM-1, MCP-1, uDKK-3, and uUMOD. The serum markers sKIM-1 and sUMOD were also analyzed. RESULTS: A positive and strong correlation was observed between the degree of interstitial fibrosis (rho = 0.785, p = .001) and tubular atrophy (rho = 0.781, p = .001) and the levels of uDKK3. uUMOD also showed an inverse and moderate correlation with interstitial fibrosis (rho = -0.562, p = .037) and tubular atrophy (rho = -0.694, p = .006). Patients with >10% cortical interstitial inflammation had higher levels of uKIM-1 [4.9 (3.9, 5.5) vs. 0.8 (0.6, 1.5) mcg/mg, p = .001], MCP-1 [3.8 (2. 3, 4.2) vs. 0.7 (0.3, 1.2) mcg/mg, p = .001], sKIM-1 [9.2 (5.9, 32.7) vs. 1.4 (0, 3.5) pg/mL, p = .001], and lower sUMOD [8.7 (0, 39.7) vs. 46.1 (35.7, 53) ng/mL, p = .028]. CONCLUSION: The use of specific urinary and serum biomarkers of tubular dysfunction or injury may help to predict certain histologic parameters in LN patients.

Tubular biomarkers in proteinuric kidney disease: histology correlation and kidney prognosis of tubular biomarkers.

Background: Proteinuria is not only a biomarker of chronic kidney disease (CKD) but also a driver of CKD progression. The aim of this study was to evaluate serum and urinary tubular biomarkers in patients with biopsied proteinuric kidney disease and to correlate them with histology and kidney outcomes. Methods: A single-center retrospective study was conducted on a cohort of 156 patients from January 2016 to December 2021. The following urinary and serum biomarkers were analyzed on the day of kidney biopsy: beta 2 microglobulin (ß2-mcg), alpha 1 microglobulin (α1-mcg), neutrophil gelatinase-associated lipocalin (NGAL), urinary kidney injury molecule-1 (uKIM-1), monocyte chemoattractant protein-1 (MCP-1), urinary Dickkopf-3 (uDKK3), uromodulin (urinary uUMOD), serum kidney injury molecule-1 (sKIM-1) and serum uromodulin (sUMOD). A composite outcome of kidney progression or death was recorded during a median follow-up period of 26 months. Results: Multivariate regression analysis identified sUMOD (ß-0.357, P < .001) and uDKK3 (ß 0.483, P < .001) as independent predictors of interstitial fibrosis, adjusted for age, estimated glomerular filtration rate (eGFR) and log proteinuria. Elevated levels of MCP-1 [odds ratio 15.61, 95% confidence interval (CI) 3.52-69.20] were associated with a higher risk of cortical interstitial inflammation >10% adjusted for eGFR, log proteinuria and microhematuria. Upper tertiles of uDKK3 were associated with greater eGFR decline during follow-up. Although not a predictor of the composite outcome, doubling of uDKK3 was a predictor of kidney events (hazard ratio 2.26, 95% CI 1.04-4.94) after adjustment for interstitial fibrosis, eGFR and proteinuria. Conclusions: Tubular markers may have prognostic value in proteinuric kidney disease, correlating with specific histologic parameters and identifying cases at higher risk of CKD progression.

Sodium-glucose cotransporter 2 inhibition in primary and secondary glomerulonephritis.

BACKGROUND: The role of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in the management glomerular/systemic autoimmune diseases with proteinuria in real-world clinical settings is unclear. METHODS: This is a retrospective, observational, international cohort study. Adult patients with biopsy-proven glomerular diseases were included. The main outcome was the percentage reduction in 24-h proteinuria from SGLT2i initiation to 3, 6, 9 and 12 months. Secondary outcomes included percentage change in estimated glomerular filtration rate (eGFR), proteinuria reduction by type of disease and reduction of proteinuria ≥30% from SGLT2i initiation. RESULTS: Four-hundred and ninety-three patients with a median age of 55 years and background therapy with renin-angiotensin system blockers were included. Proteinuria from baseline changed by -35%, -41%, -45% and -48% at 3, 6, 9 and 12 months after SGLT2i initiation, while eGFR changed by -6%, -3%, -8% and -10.5% at 3, 6, 9 and 12 months, respectively. Results were similar irrespective of the underlying disease. A correlation was found between body mass index (BMI) and percentage proteinuria reduction at last follow-up. By mixed-effects logistic regression model, serum albumin at SGLT2i initiation emerged as a predictor of ≥30% proteinuria reduction (odds ratio for albumin <3.5 g/dL, 0.53; 95% CI 0.30-0.91; P = .02). A slower eGFR decline was observed in patients achieving a ≥30% proteinuria reduction: -3.7 versus -5.3 mL/min/1.73 m2/year (P = .001). The overall tolerance to SGLT2i was good. CONCLUSIONS: The use of SGLT2i was associated with a significant reduction of proteinuria. This percentage change is greater in patients with higher BMI. Higher serum albumin at SGLT2i onset is associated with higher probability of achieving a ≥30% proteinuria reduction.

Obesity, chronic kidney disease progression and the role of the adipokine C1q/TNF related protein-3.

INTRODUCTION AND AIMS: Obesity is a risk factor for incident chronic kidney disease (CKD). C1q/TNF related protein 3 (CTRP3) is an adipokine with multiple effects and may modulate the association between obesity and vascular diseases. The aim of the study is to explore potential links between obesity, CTRP3 levels and CKD progression. METHODS: Patients with stage 3 and 4 CKD without previous cardiovascular events were enrolled and divided into groups according to body mass index (BMI) and sex. Demographic, clinical, analytical data and CTRP3 levels were collected at baseline. During follow-up, renal events (defined as dialysis initiation, serum creatinine doubling or a 50% decrease in estimated glomerular filtration rate were registered). RESULTS: 81 patients were enrolled. 27 were obese and 54 non-obese. Baseline CTRP3 was similar between both groups (90.1±23.8 vs 84.5±6.2; p=0.28). Of the sum, 54 were men and 27 women, with higher CTRP3 in women (81.4±24.7 vs 106±24.7;p<0.01). During a mean follow-up of 68 months, 15 patients had a renal event. Patients in the higher CTRP3 tertile had less events but without statistical significance (p=0.07). Obese patients in the higher CTRP3 tertile significantly had less renal events (p=0.049). By multiple regression analysis CTRP3 levels could not predict renal events (HR 0.98; CI95% 0.96-1.06). CONCLUSIONS: CTRP3 levels are higher in woman than men in patients with CKD, with similar levels between obese and non obese. Higher CTRP3 levels at baseline were associated with better renal outcomes in obese patients.

Use of renin-angiotensin-aldosterone system blockade in controversial chronic kidney disease populations.

Renin-angiotensin-aldosterone system blockers have shown to be effective in controlling blood pressure and proteinuria, slowing the progression to end stage renal disease and reducing cardiovascular risk, so they are the mainstream treatment of hypertension in chronic kidney disease. Their beneficial effects have been proven in multiple randomized clinical trials on different study populations, but there has recently been some controversial data on its use in some subgroups of patients, especially those with advanced chronic kidney disease. In some other populations such as patients with non-proteinuric nephropathies or the elderly, who can be more susceptible to its adverse events, their benefits have also been questioned. The aim of the present review is to collect available published data on the effect of renin-angiotensin-aldosterone system blockers in some controversial populations and provide perspective on future research areas in this field.

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.

Obesity and chronic kidney disease progression-the role of a new adipocytokine: C1q/tumour necrosis factor-related protein-1.

BACKGROUND: Obesity is a risk factor for incident chronic kidney disease (CKD) in the general population. C1q/tumour necrosis factor-related protein 1 (CTRP1) is a new adipokine with multiple vascular and metabolic effects and may modulate the association between obesity and vascular diseases. The aim of the study is to explore potential links between obesity, CTRP1 levels and CKD progression. METHODS: Patients with Stages 3 and 4 CKD without previous cardiovascular events were enrolled and divided into two groups according to body mass index (BMI). Demographic, clinical and analytical data and CTRP1 levels were collected at baseline. During follow-up, renal events [defined as dialysis initiation, serum creatinine doubling or a 50% decrease in estimated glomerular filtration rate (Modification of Diet in Renal Disease)] were registered. RESULTS: A total of 71 patients with CKD were divided into two groups: 25 obese (BMI >30 kg/m2) and 46 non-obese. CTRP1 in plasma at baseline was higher in obese patients [median (interquartile range) 360 (148) versus 288 (188) ng/mL, P = 0.041]. No significant association was found between CTRP1 levels and CKD stage, presence of diabetes, aldosterone and renin levels, or blood pressure. Obese patients had higher systolic blood pressure (P = 0.018) and higher high-sensitivity C-reactive protein (P = 0.019) and uric acid (P = 0.003) levels, without significant differences in the percentage of diabetic patients or albuminuria. During a mean follow-up of 65 months, 14 patients had a renal event. Patients with CTRP1 in the lowest tertile had more renal events, both in the overall sample (log rank: 5.810, P = 0.016) and among obese patients (log rank: 5.405, P = 0.020). Higher CTRP1 levels were associated with slower renal progression (hazard ratio 0.992, 95% confidence interval 0.986-0.998; P = 0.001) in a model adjusted for obesity, aspirin, albuminuria and renal function. CONCLUSIONS: CTRP1 levels are higher in obese than in non-obese patients with CKD. High CTRP1 levels may have a renal protective role since they were associated with slower kidney disease progression. Interventional studies are needed to explore this hypothesis.

Pentoxifylline, progression of chronic kidney disease (CKD) and cardiovascular mortality: long-term follow-up of a randomized clinical trial.

BACKGROUND: Pentoxifylline could reduce proteinuria and slow renal disease progression. We previously conducted a single-blind, randomized, controlled trial that showed that pentoxifylline decreases inflammatory markers and stabilizes renal function. SETTING AND PARTICIPANTS: 91 participants (46 in the pentoxifylline group and 45 in the control group) followed up for 7 additional years. STUDY DESIGN: Post hoc analysis of a long-term follow-up after completion of the 12-months trial. INTERVENTION: Pentoxifylline treatment (400 mg/twice a day) or standard treatment. OUTCOME: Renal event (defined as starting dialysis therapy and/or doubling serum creatinine and/or ≥ 50% decrease in estimated glomerular filtration rate) and cardiovascular mortality. RESULTS: During follow-up, a renal event was recorded in 24 patients from control group (13 initiated dialysis therapy and serum creatinine doubled in 11) and 11 patients from PTF group (7 initiated dialysis and serum creatinine doubled in 4) (log Rank: 5.822, p = 0.016). The possible protector effect of PTF was more significant in albuminuric patients and was independently of diabetes mellitus presence. Treatment with PTF reduced the renal events by 35% compared to the control group in a Cox model adjusted for diabetes mellitus, albuminuria and basal renal function (HR 0.65 (0.45-0.94), p = 0.022). Cardiovascular mortality was significantly reduced in PTF treatment (2 patients vs. 10 in control group) (log Rank 5.0977, p = 0.024). PTF treatment reduced cardiovascular mortality in 55% adjusted for diabetes mellitus and age (HR 0.45 (0.21-0.98), p = 0.044) (Table 3). LIMITATIONS: Small sample size, single center, not double blind and post hoc follow-up analysis. CONCLUSIONS: Long-term treatment with pentoxifylline may slow the rate of progression of kidney disease and reduce cardiovascular risk.

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.

High convective volumes are associated with improvement in metabolic profile in diabetic patients on online haemodiafiltration. / Los altos volúmenes convectivos se asocian a la mejoría del perfil metabólico en los pacientes diabéticos en hemodiafiltración online.

BACKGROUND AND OBJECTIVE: Online haemodiafiltration (OL-HDF) with high convective transport volumes improves patient survival in haemodialysis. Limiting the amount of convective volume has been proposed in patients with diabetes mellitus due to glucose load that is administered with replacement fluid. The objective of the study was to analyse the influence of substitution volume on the evolution of the metabolic profile and body composition of incident diabetic patients on OL-HDF. MATERIAL AND METHODS: Prospective observational study in 29 incident diabetic patients on postdilution OL-HDF. Baseline data included clinical and demographic data, laboratory parameters (metabolic, nutritional and inflammatory profile) and body composition with bioimpedance spectroscopy (BIS). Laboratory parameters and mean substitution volume per session were collected every 4 months, and in 23 patients a further BIS was performed after a minimum of one year. Variations in glycosylated haemoglobin (HbA1c), triglycerides, total cholesterol, LDL-c, HDL-c, albumin, prealbumin and C reactive protein (CRP) were calculated at one year, 2 years, 3 years, and at the end of follow-up. Quarterly and annual variations were calculated as independent periods, and changes in body composition were analysed. RESULTS: Age at baseline was 69.7±13.6 years, 62.1% were male, 72.3±13.9kg, 1.78±0.16m2, with 48 (35.5-76) months on dialysis. Approximately 81.5% received insulin, 7.4% antidiabetic drugs and 51.9% statins. Mean substitution volume was 26.9±2.9L/session and follow-up period (time on OL-HDF) was 40.4±26 months. A significant correlation was observed between mean substitution volume and the increase in HDL-c (r=0.385, p=0.039) and prealbumin levels (r=0.404, p=0.003) throughout follow-up. Moreover, substitution volume was correlated with a reduction in CRP levels at one year (r=-0.531, p=0.005), 2 years (r=-0.463, p=0.046), and at the end of follow-up (r=-0.498, p=0.007). Patients with mean substitution volume >26.9L/session had a higher reduction in triglycerides and CRP, and an increase in HDL-c levels. These patients with >26.9L/session finished the study with higher HDL-c (48.1±9.4mg/dL vs. 41.2±11.6mg/dL, p=0.025) and lower CRP levels (0.21 [0.1-2.22] mg/dL vs. 1.01 [0.15-6.96] mg/dL, p=0.001), with no differences at baseline. Quarterly comparisons between substitution volume and laboratory changes [n=271] showed a significant correlation with a reduction in HbA1c (r=-0.146, p=0.021). Similar findings were obtained with annual comparisons [n=72] (r=-0.237, p=0.045). An annual mean substitution volume over 26.6L/session (29.3±1.7L/session vs. 23.9±1.9L/session) was associated with a reduction in HbA1c (-0.51±1.24% vs. 0.01±0.88%, p=0.043). No correlation was observed between substitution volume and changes in weight, body mass index or BIS parameters. CONCLUSION: There is not enough evidence to restrict convective transport in diabetic patients on OL-HDF due to the glucose content of the replacement fluid.

Impact of the application of the JNC 8 and KDIGO-2013 guidelines on hypertension and lipid control in a Nephrology outpatient clinic. / Impacto de la aplicación del 8.o JNC y de las guías KDIGO-2013 en el control de la hipertensión arterial y los lípidos en una consulta de Nefrología.

OBJECTIVE: Observational retrospective study with consecutive patients with CKD to assess the degree of accomplishment of the therapeutic objectives in hypertension and dyslipidaemia recommended by JNC 8 and KDIGO-2013 CKD guidelines the impact of their implementation compared with previous guidelines. RESULTS: 618 patients were included, mean age 67±15 years, 61.33% male. Mean eGFR was 45.99±18.94ml/min, with median albumin/creatinine 26 (0-151)mg/g. A total of 87.6% received antihypertensive treatment and 50.2% received statins. According to KDIGO guidelines, 520 patients (84.14%) should receive statins, but only 304 (58.46%) were receiving them. Patients on statin treatment had more diabetes and hypertension, and a greater cardiovascular history and lower levels of total and LDL-cholesterol. A total of 97.7% of patients were under 60 years of age or had eGFR<60ml/min/1.73m2 or were diabetic, so according to the JNC 8 report, they should have a target blood pressure<140/90mmHg. A total of 289 patients did (47.85%). According to the JNC 7 report, this group had a tighter target blood pressure<130/90mmHg, reducing the number of patients who fulfilled the target: 136 (22.52%). Patients reclassified were older, had a greater cardiovascular history and less DM. CONCLUSION: The new KDIGO guidelines for dyslipidaemia treatment increase the indication of statin therapy, especially in patients at high cardiovascular risk. The JNC 8 guidelines improve the percentage of patients with controlled blood pressure, especially the elderly and patients with increased cardiovascular risk, in whom the target blood pressure is currently controversial.

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.

Impact of anticoagulation and platelet antiaggregation on anaemia and haemorragic events in patients with chronic kidney disease stages 3 and 4. / Impacto de la anticoagulación y antiagregación plaquetaria en la anemia y los eventos hemorrágicos y ateroscleróticos de pacientes con enfermedad renal crónica en estadios 3 y 4.

BACKGROUND AND OBJECTIVE: There is controversy concerning the risk/benefit of anticoagulation/antiaggregation in chronic kidney disease (CKD) patients. We analysed the impact of anticoagulation/antiaggregation on anaemia and haemorrhagic events in CKD patients. PATIENTS AND METHODS: A total of 232 CKD patients stages 3 and 4 were followed during a mean follow-up time of 36.7 ± 11.6 months: 81 patients did not receive any anticoagulation or antiaggregation treatment, 91 received anticoagulation treatment and 60 patients received platelet antiaggregation. Haemorrhagic and cardiovascular events were recorded. RESULTS: Haemoglobin and ferritine levels were significantly higher in patients who did not receive anticoagulation or antiaggregation (Hb 13.7 ± 1.6, 13.3 ± 1.8 and 12.7±1.9g/dl, p=0.004; ferritine 170 ± 145, 140 ± 138, 105 ± 99µg/l, p=0.023). During follow up, 36 haemorrhagic events were registered: 4in the control group, 23 in the anticoagulation group and 9in the antiaggregation group (log rank 12.5; p=0.002). In a Cox model adjusted by age, renal function and haemoglobin levels, the anticoagulation increased the risk of bleeding by 4times (HR 4.180, 1.955-8.937); p=0,001) and antiaggregation by almost 3times (HR 2.780, 1.257-6.149, p=0.012). A total of 64 cardiovascular events were registered, 21 of which were classified as atherosclerotic events: 10 in the antiaggregation group, 8in the control group and 3in the anticoagulation group (log rank: 8.351; p=0.015). Anticoagulation treatment showed a reduction in the risk of atherosclerotic events (HR 0.136, 0.033-0.551, p=0.005) while platelet antiaggregation did not modified this risk (HR 1,566, 0.569-4.308). CONCLUSIONS: Anticoagulation and antiaggregation increase haemorrhagic risk in patients with CKD and worsen anaemia. Anticoagulation reduces atherosclerotic events by more than 85% while platelet antiaggregation does not modify this risk.

Hyperuricemia is associated with progression of chronic kidney disease in patients with reduced functioning kidney mass.

BACKGROUND AND OBJECTIVES: Hyperuricemia plays a major role in the development and progression of chronic kidney disease (CKD). Many large observational studies have indicated that increased serum uric acid level predicts the development and progression of CKD in some population, however this hypothesis has not been yet studied in patients with reduced renal mass. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Retrospective study with a cohort of 324 patients with reduced renal mass from an outpatient basis, followed during 60 (36-98) months. Demographics variables, cardiovascular factors, concomitant medications, albuminuria and uric acid levels were recorded yearly. The primary endpoint was the annual fall of estimated glomerular filtration rate (eGFR) by MDRD-4. The sample was divided into three successive groups (A1: patients with fall of eGFR lower than median, A2: greater than median, B: without fall of eGFR). Factors associated and predictors of kidney function decline were analyzed. RESULTS: One hundred and seventy out of 324 patients suffered a fall of eGFR (group A), (median of fall -1.6ml/min/1.73m2/year (-3.0, -0.7)). Male gender, albuminuria>100mg/day and higher pulse pressure were associated to progression in our cohort (group A). Hyperuricemia was more frequent among patients with higher kidney disease progression (group A2) (33% vs 49%, p=0.04) when comparing to lower progression (group A1). Adjusted Cox regression models showed that hyperuricemia, pulse pressure and albuminuria were independent predictors of kidney disease progression (HR 1.67 (1.06-2.63), p=0.023; 1.02 (1.01-1.03), p=0.001 and HR: 2.14 (1.26-3.64), p=0.005, respectively). Kidney disease progression was higher in patients with unilateral renal atrophy or agenesis than nephrectomy (log rank: 7.433, p=0.006). CONCLUSIONS: Hyperuricemia is independently associated with kidney disease progression in patients with reduce functioning renal mass.

Low dose aspirin increases 15-epi-lipoxin A4 levels in diabetic chronic kidney disease patients.

BACKGROUND: Resolution of inflammation is regulated by endogenous lipid mediators, such as lipoxins and their epimers, including 15-epi-lipoxin A4 (15-epi-LXA4). However, there is no information on 15-epi-LXA4 and its in vivo regulation in chronic kidney disease (CKD) patients. STUDY DESIGN: Open label randomized clinical trial. SETTING AND PARTICIPANTS: 50 participants with chronic kidney disease (CKD) stage 3 and 4 without prior cardiovascular disease (25 in the aspirin group and 25 in the standard group) followed for 46 months. INTERVENTION: Aspirin (100mg/day) or standard treatment. AIM: To analyze the effect of aspirin on plasma 15-epi-LXA4 levels and inflammatory markers in CKD patients. RESULTS: Baseline plasma15-epi-LXA4 levels were lower in diabetic (1.22 ± 0.99ng/ml) than in non-diabetic CKD patients (2.05 ± 1.06ng/ml, p < 0.001) and inversely correlated with glycosylated hemoglobin levels (r = -0.303, p = 0.006). In multivariate analysis, diabetes was associated with lower 15-epi-LXA4 levels, adjusted for age, inflammatory markers and renal function (p = 0.005). In the whole study population, 15-epi-LXA4 levels tended to increase, but not significantly (p = 0.45), after twelve months on aspirin (from mean ± SD 1.84 ± 1.06 to 2.04 ± 0.75ng/ml) and decreased in the standard care group (1.60 ± 1.15 to 1.52 ± 0.68ng/ml, p = 0.04). The aspirin effect on 15-epi-LXA4 levels was more striking in diabetic patients, increasing from 0.94 ± 0.70 to 1.93 ± 0.74ng/ml, p = 0.017. CONCLUSIONS: Diabetic patients with CKD have lower circulating 15-epi-LXA4 levels than non-diabetic CKD patients. Low dose aspirin for 12 months increased 15-epi-LXA4 levels in diabetic patients. Given its anti-inflammatory properties, this increase in 15-epi-LXA4 levels may contribute to the beneficial effects of low dose aspirin.

Cardiovascular risk prediction in chronic kidney disease patients. / Predicción del riesgo cardiovascular en pacientes con enfermedad renal crónica.

INTRODUCTION: Scores underestimate the prediction of cardiovascular risk (CVR) as they are not validated in patients with chronic kidney disease (CKD). Two of the most commonly used scores are the Framingham Risk Score (FRS-CVD) and the ASCVD (AHA/ACC 2013). The aim of this study is to evaluate the predictive ability of experiencing a cardiovascular event (CVE) via these 2scores in the CKD population. MATERIAL AND METHODS: Prospective, observational study of 400 prevalent patients with CKD (stages 4 and 5 according the KDOQI; not on dialysis). Cardiovascular risk was calculated according to the 2scores and the predictive capacity of cardiovascular events (atherosclerotic events: myocardial infarction, ischaemic and haemorrhagic stroke, peripheral vascular disease; and non-atherosclerotic events: heart failure) was analysed. RESULTS: Forty-nine atherosclerotic cardiovascular events occurred in 40.3±6.6 months of follow-up. Most of the patients were classified as high CVR by both scores (59% by the FRS-CVD and 75% by the ASCVD). All cardiovascular events occurred in the high CVR patients and both scores (FRS-CVD log-rank 12.2, P<.001, HR 3.1 [95% CI: 1.3-7.1] P: 0.006 and ASCVD log-rank 8.5 P<.001, HR 3.2 [95% CI: 1.1-9.4] P: 0.03) were independent predictors adjusted to renal function, albuminuria and previous cardiovascular events. CONCLUSION: The cardiovascular risk scores (FRS-CVD and ASCVD [AHA/ACC 2013]) can estimate the probability of atherosclerotic cardiovascular events in patients with CKD regardless of renal function, albuminuria and previous cardiovascular events.

Prevalence and characteristics of patients with resistant hypertension and chronic kidney disease. / Prevalencia y características de los pacientes con hipertensión arterial resistente y enfermedad renal crónica.

Resistant hypertension (RH) is a common problem in patients with chronic kidney disease (CKD). A decline in the glomerular filtration rate (GFR) and increased albuminuria are associated with RH; however, there are few published studies about the prevalence of this entity in patients with CKD. OBJECTIVE: To estimate the prevalence of RH in patients with different degrees of kidney disease and analyse the characteristics of this group of patients. METHODS: A total of 618 patients with hypertension and CKD stages i-iv were enrolled, of which 82 (13.3%) met the criteria for RH. RESULTS: RH prevalence increased significantly with age, the degree of CKD and albuminuria. The prevalence of RH was 3.2% in patients under 50 years, 13.8% between 50-79 years and peaked at 17.8% in patients older than 80 years. Renal function prevalence was 4, 15.8 and 18.1% in patients with an estimated glomerular filtration rate (GFR) of > 60, 30-59 and < 30ml/min/1.73 m2, respectively, and 8.9, 15.9 and 22.5% for a urine albumin to creatinine ratio (UACR) < 30, 30-299 and > 300mg/g respectively. In a logistic regression model, the characteristics associated with resistant hypertension were age, history of cardiovascular disease, GFR, albuminuria and diabetes mellitus. A total of 47.5% of patients with resistant hypertension had controlled BP (<140/90mmHg) with 4 or more antihypertensive drugs. These patients were younger, with better renal function, less albuminuria and received more aldosterone antagonists. CONCLUSION: RH prevalence increases with age, the degree of CKD and albuminuria. Strategies such as treatment with aldosterone receptor antagonists are associated with better blood pressure control in this group of patients, leading to reduced prevalence.

The effect of some medications given to CKD patients on vitamin D levels.

BACKGROUND: Vitamin D deficiency and polypharmacy is a common problem over chronic kidney disease (CKD) population. OBJECTIVES: To assess the clinical and analytical characteristics of CKD patients with 25-OH-D3 deficiency (<15 ng/mL), including the possible role of associated drugs. METHODS: A single center observational review of 137 incident patients referred to our outpatient clinic with different stages of CKD and 25-OH-D3<15ng/mL (male gender 53.3%, mean age 70.8 [±16.1] years, mean GFR (MDRD-4) 43.6 [±25.5] ml/min/1.73 m²). 25-OH-D3 levels were collected in spring. Clinical and biochemical data and associated medications were recorded. RESULTS: Mean 25-OH-D3 levels were 8.23 [±4.03] ng/ml. Eighty-eight patients (64.7%) had 3 or more concomitant drugs. Only 7 patients (5.1%) were not receiving any medication. Patients were divided in three groups according the therapies into none (n=26), RAS inhibitors or allopurinol (n=81), and RAS inhibitors plus allopurinol (n=30); with the aim to study the influence of statin therapy. Patients under renin angiotensin (RAS) inhibitors or Allopurinol treatment presented significantly higher 25-OH-D3 levels (p=0.001 and p=0.01 respectively), however patients with Statins treatment had lower 25-OH-D3 level (p=0.039). Personal history of diabetes, cardiovascular events or other therapies did not modify 25-OH-D3 levels, adjusted by age and eGFR. CONCLUSIONS: CKD patients with vitamin D deficiency who received RAS inhibitors or Allopurinol treatment had higher 25-OH-D3 levels, however those with statins treatment had lower vitamin D levels. Randomized controlled trials are required to confirm these findings.