Pica en enfermedad renal crónica avanzada: revisión de la literatura

Pica is an individual entity in the patient with chronic kidney disease (CKD), which phenomenon has not been widely studied despite the high reported prevalence. Moreover, pica complications (anemia, altered electrolytes, poor absorption of micro and macronutrients and malnutrition) could be exacerbated in CKD and limit the quality of renal replacement therapy.The intake of non-caloric and non-nutritional substances could be harmful and cause effects on satiety and metabolic / electrolyte imbalance and modify the biocompatibility of micronutrients, toxins and pathogens worsening health status.In daily practice, pica could be under-reported because patient's shame to recognize it, or fear that such behavior influences their treatment. Additionally, clinicians who not investigate the presence of pica or its complications contribute to the lack of information about the magnitude and relevance of this problem in CKD.     

Nuevo enfoque en el tratamiento nutricional de la enfermedad renal crónica avanzada

IntroductionPatients with advanced chronic kidney disease (ACKD) have a high prevalence of malnutrition. The dietary restrictions that we usually apply in terms of macro and micronutrients force our patients to follow dietary guidelines that deviate from healthy patterns.ObjectivesTo determine if a personalized nutritional intervention program, minimizing the usual restrictions would be justified in case it improved the evolution of kidney disease compared to standard treatment.Secondary objectivesTo determine changes in nutrient intakes and in anthropometric and biochemical parameters, as well as quantify episodes of hyperkalemia.Material and methodsA single-center, randomized and controlled educational intervention clinical trial was conduct in patients from the ERCA outpatients clinic at the Complejo Hospitalario Universitario de Albacete. 75 patients were included, assigning 35 to a Control group and 40 to the Intervention group with 1-year follow-up. The nutritional status was determined using anthropometric data, body composition by Bioimpedance, blood and urine biochemical parameters and a 24-h recall questionnaire. The nutritional intervention was carried out in three different ways: individual, collective and telephone recall.ResultsAt the beginning of the study, the BMI showed a situation of weight excess with a mean of 28.83 kg/m² (5.4) in men and 26.96 kg/m² (4.09) in women. 70% of our patients had overweight. The abdominal circumference was 105.3 cm (10.2) and 92.3 cm (13.7) for men and women respectively without significant changes throughout the study. The percentage of fat mass (FM) was high in both groups for men and women throughout the study. We did not find biochemical parameters of malnutrition and only significant differences were observed in glomerular filtration rate (GFR), which increased in the intervention group. No patient presented any episodes of hyperkalemia during the study. The energy intake in both groups showed an inadequate distribution of macronutrients with a poor intake of carbohydrates (CH) that was supplemented with an excess of fat. In the case of micronutrients, we did observe an increase in potassium and fiber intakes with a decrease in sodium and phosphorus in the intervention group.ConclusionsMalnutrition is not exclusively an intake deficit and encompasses both the problems derived from a deficit and an excess of nutrients intake. Un to 70% of our patients showed weight excess and a fat mass higher than desirable. The implementation of an individualized nutritional education program, including a vegetables and fiber rich diet, less atherogenic, not only did not cause electrolyte alterations but also slowed the progression of kidney disease.     

Asociación entre hiperkaliemia y evolución clínica en la enfermedad renal crónica avanzada

IntroductionPatients with advanced chronic kidney disease (CKD) are at greatest risk of hyperkalemia (HK). The relationship between HK and negative outcomes (mortality or progression of renal insufficiency) in non-dialysis dependent CKD patients is controversial.AimsTo determine the incidence, prevalence, and factors related with HK in a cohort of CKD patients, and its relationship with mortality, hospitalization rate, CKD progression, and dialysis initiation.Material and methodsA retrospective, observational study in an incident cohort of adult patients with stage 4 or 5 CKD not on dialysis. Inclusion criteria were: having at least three consecutive estimated glomerular filtration rate (eGFR) measurements in a follow-up period >3 months. Decline in renal function was estimated as the slope of the individual linear regression line of eGFR over follow-up time. HK was defined as serum K levels ≥5.5 meq/l. Associations of HK with outcomes were adjusted for major confounding variables in the multivariate analysis.ResultsThe study group consisted of 1079 patients (574 males, mean age: 65±14 years) with mean baseline eGFR 14.8±4.5 ml/min/1,73 m². Mean follow-up time was 15 months with a median of 7 serum sample determinations per patient. HK was observed at baseline in 26% of patients; in at least one serum sample during the individual follow-up period in 68%; or chronically (>50% of samples) in 33% of patients. By multivariate logistic regression, the best determinants of chronic HK were: male sex (OR = 1.529; 95% CI [1.154-2.025], p = .003), serum bicarbonate (OR = 0.863 [0.829-0.900], p <.0001), diuretic treatment (OR = 0.743 [0.556-0.992], p = .044), and angiotensin converting enzyme inhibitor and/or angiotensin receptor blockers (OR = 4.412 [2.915-6.678], p <.0001). Patients whose serum K levels were in the upper quartile showed a significantly faster CKD progression (?4.05±5.22 vs. ?2.69±5.61 ml/min/1.73 m²/year, p <.0001), and more frequent dialysis initiation (63% vs. 57%, p = .115), though lower mortality (9% vs. 17%, p = .003) and hospitalization rates (2.68±5.94 vs. 3.16±6.77 days per year, p = .301) than the other study patients. However, in the multivariate analysis, average serum K levels were not independently associated with the clinical outcomes investigated.ConclusionHK is a common biochemical finding in non-dialysis dependent CKD patients, mainly associated with prescribed medication. However, HK was not independently associated with major negative clinical outcomes.     

Impacto del consumo de alimentos ultraprocesados en la enfermedad renal crónica

The modern diet is closely linked to the consumption of processed foods, causing an increase in the intake of salt, simple sugars, phosphorus and added potassium. This excess intake is associated with an increased risk of obesity, diabetes, hypertension and chronic kidney disease (CKD). CKD, which according to data from the ENRICA study affects 15% of the population, magnifies its impact due to the higher prevalence of diabetes and hypertension and due to limitations in the management of sodium and phosphorus. The intake of these products far exceeds the established recommendations, assuming 72% of total sodium, 25-35% of phosphorus, 12-18% of potassium and exceeding 10% of the caloric intake in simple sugars. Measures are necessary to reduce their contribution through nutritional advice, labeling review, education campaigns on healthy habits, fees and institutional actions that involve food safety agencies, industry, distribution and scientific societies.     

Bloqueantes del receptor mineralcorticoide en la enfermedad renal crónica

There are many experimental data supporting the involvement of aldosterone and mineralcorticoid receptor (MR) activation in the genesis and progression of chronic kidney disease (CKD) and cardiovascular damage.Many studies have shown that in diabetic and non-diabetic CKD, blocking the renin- angiotensin-aldosterone (RAAS) system with conversion enzyme inhibitors (ACEi) or angiotensin II receptor blockers (ARBs) decreases proteinuria, progression of CKD and mortality, but there is still a significant residual risk of developing these events.In subjects treated with ACEi or ARBs there may be an aldosterone breakthrough whose prevalence in subjects with CKD can reach 50%. Several studies have shown that in CKD, the aldosterone antagonists (spironolactone, eplerenone) added to ACEi or ARBs, reduce proteinuria, but increase the risk of hyperkalemia. Other studies in subjects treated with dialysis suggest a possible beneficial effect of antialdosteronic drugs on CV events and mortality. Newer potassium binders drugs can prevent / decrease hyperkalemia induced by RAAS blockade, and may reduce the high discontinuation rates or dose reduction of RAAS-blockers.The nonsteroidal MR blockers, with more potency and selectivity than the classic ones, reduce proteinuria and have a lower risk of hyperkalemia. Several clinical trials, currently underway, will determine the effect of classic MR blockers on CV events and mortality in subjects with stage 3b CKD and in dialysis patients, and whether in patients with type 2 diabetes mellitus and CKD, optimally treated and with high risk of CV and kidney events, the addition of finerenone to their treatment produces cardiorenal benefits.Large randomized trials have shown that sodium glucose type 2 cotransporter inhibitors (SGLT2i) reduce mortality and the development and progression of diabetic and nondiabetic CKD. There are pathophysiological arguments, which raise the possibility that the triple combination ACEi or ARBs, SGLT2i and aldosterone antagonist provide additional renal and cardiovascular protection.     

Manejo renal del potasio en la enfermedad renal crónica avanzada: diferencias entre pacientes con o sin hipercaliemia

IntroductionHyperkalemia (HK) is a common electrolyte disorder in chronic kidney disease (CKD), mainly in the advanced stages. A positive potassium balance due to reduced renal excretory capacity is likely the main pathogenic mechanism of HK. Research into the relative role of each pathogenic element in the development of HK in CKD may help to implement more suitable therapies.ObjectiveTo investigate renal potassium handling in advanced CKD patients, and to determine the differences between patients with or without HK.Material and methodsCross-sectional observational study in adult patients with stage 4-5 CKD pre-dialysis. Selection criteria included clinically stable patients and the ability to collect a 24 hour urine sample correctly. Blood and urinary biochemical parameters were analysed including sodium and potassium (K). Fractional excretion of K (FEK) and K load relative to glomerular filtration (Ku/GFR) were calculated. HK was defined as a serum K concentration ≥ 5.5 mmol/l.ResultsThe study group consisted of 212 patients (mean age 65 ± 14 years, 92 females) with a mean GFR of 15.0 ± 4.2 ml/min/1.73 m². 63 patients (30%) had HK. Patients with HK had lower mean bicarbonate levels with respect to patients with normal K levels (NK) (20.3 ± 3.1 vs. 22.8 ± 3.2 mEq/l, P < .0001), but no differences were noted in total urinary sodium and K excretion. While mean FEK values were lower in patients with HK (32.1 ± 12.1% vs. 36.4 ± 14.3%, P = .038), Ku/GFR values were significantly greater with respect to the NK subgroup (4.2 ± 1.5 vs. 3.7 ± 1.4 mmol/ml/min, P = 0,049). FEK showed a strong linear correlation with Ku/GFR (R² = 0.74), and partial linear regressions demonstrated that at a similar Ku/GFR level, the FEK of patients with HK was lower than that of NK patients. By multivariate linear and logistic regression analyses, both FEK and Ku/GFR were shown to be the main determinants of K serum levels and HK.ConclusionsAlthough the K load relative to glomerular filtration (Ku/GFR) is an important determinant of HK in advanced CKD, the most noteworthy characteristic associated with HK in these patients was the limitation of compensatory urinary K excretion, as indicated by lower FEK.     

Acidosis metabólica en la enfermedad renal crónica: dificultades para una corrección adecuada

IntroductionMetabolic acidosis (MA) is a common complication of chronic kidney disease (CKD) and is associated with numerous adverse effects, which is why its correction is highly recommended. Oral sodium bicarbonate is the current treatment of choice.ObjectivesTo describe the prevalence of MA in advanced CKD patients and to determine the clinical and biochemical characteristics associated with its successful correction.Material and methodsRetrospective, observational cohort study in adult patients with CKD stage 4-5. The inclusion criteria were: not being treated with alkali therapy at the time of inclusion, and to have at least three consecutive glomerular filtration rate (GFR) measurements and biochemical parameters during a minimum follow-up period of 3 months. Incident patients with serum bicarbonate < 22 mEq/l were included in the follow-up study and treated with oral sodium bicarbonate. Correction was considered successful when more than half of the samples and the mean bicarbonate levels during individual follow-up were ≥ 22 mEq/l.ResultsThe study group consisted of 969 patients (age 65 ± 14 years, 507 males) with a mean GFR of 14.8 ± 4.5 ml/min/1.73 m². At baseline, 530 patients (55%) had serum bicarbonate < 22 mEq/l. They were treated with sodium bicarbonate and followed for 15 months. Satisfactory correction of MA was only achieved in 133 patients (25%). By multivariate logistic regression analysis, the main characteristics of patients with adequate control of MA were: age (OR = 1.03; 95% CI 1.01 – 1.05), baseline GFR (OR = 1.07; 1.02 – 1.12), and treatment with proton-pump inhibitors (OR = 1.61; 95% CI 1.06 – 2.44). Patients who achieved successful correction of MA showed slower CKD progression (-1.67 ± 3.71 vs -4.36 ± 4.56 ml/min/1.73 m²/year, P < .0001), and lower average serum potassium concentration (5.1 ± 0.5 vs 5.3 ± 0.5, P < .0001) than those who did not. However, there were no differences in the hospitalisation or mortality rate.ConclusionMA is a common complication of advanced CKD but difficult to manage with current therapies. Due to the significant potential benefit of controlling MA, new, more effective therapies should be further researched.     

Documento de información y consenso para la detección y manejo de la enfermedad renal crónica

Chronic kidney disease (CKD) is a major public health problem worldwide that affects more than 10% of the Spanish population. CKD is associated with high comorbidity rates, poor prognosis and major consumption of health system resources. Since the publication of the last consensus document on CKD seven years ago, little evidence has emerged and few clinical trials on new diagnostic and treatment strategies in CKD have been conducted, apart from new trials in diabetic kidney disease. Therefore, CKD international guidelines have not been recently updated. The rigidity and conservative attitude of the guidelines should not prevent the publication of updates in knowledge about certain matters that may be key in detecting CKD and managing patients with this disease. This document, also prepared by 10 scientific societies, provides an update on concepts, clarifications, diagnostic criteria, remission strategies and new treatment options.The evidence and the main studies published on these aspects of CKD have been reviewed. This should be considered more as an information document on CKD. It includes an update on CKD detection, risk factors and screening; a definition of renal progression; an update of remission criteria with new suggestions in the older population; CKD monitoring and prevention strategies; management of associated comorbidities, particularly in diabetes mellitus; roles of the Primary Care physician in CKD management; and what not to do in Nephrology.The aim of the document is to serve as an aid in the multidisciplinary management of the patient with CKD based on current recommendations and knowledge.     

Documento de consenso sobre el diagnóstico y tratamiento de la infección bronquial crónica en la enfermedad pulmonar obstructiva crónica

Although the chronic presence of microorganisms in the airways of patients with stable chronic obstructive pulmonary disease (COPD) confers a poor outcome, no recommendations have been established in disease management guidelines on how to diagnose and treat these cases.In order to guide professionals, the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) has prepared a document which aims to answer questions on the clinical management of COPD patients in whom microorganisms are occasionally or habitually isolated. Since the available scientific evidence is too heterogeneous to use in the creation of a clinical practice guideline, we have drawn up a document based on existing scientific literature and clinical experience, addressing the definition of different clinical situations and their diagnosis and management. The text was drawn up by consensus and approved by a large group of respiratory medicine experts with extensive clinical and scientific experience in the field, and has been endorsed by the SEPAR Scientific Committee.     

Anticoagulación oral en la enfermedad renal crónica con fibrilación auricular

Chronic kidney disease (CKD) and atrial fibrillation (AF) frequently coexist, amplifying the risk of cardiovascular events and mortality. In patients with CKD stage 3 and non-valvular AF, direct oral anticoagulants (DOACs) have shown, compared to vitamin K antagonists (VKA), equal or greater efficacy in the prevention of stroke and systemic embolism, and greater safety. There are no randomized trials of the efficacy and safety of DOACs and VKA in advanced CKD. On the other hand, observational studies suggest that DOACs, compared to warfarin, are associated with a lower risk of acute kidney damage and generation/progression of CKD. This paper reviews the epidemiological and pathophysiological aspects of the CKD and AF association, the evidence of the efficacy and safety of warfarin and ACODs in various stages of CKD with AF as well as the comparison between warfarin and ACODs in efficacy and anticoagulant safety, and in its renal effects.     

Impacto pronóstico de la enfermedad renal crónica sobre el cierre percutáneo de la orejuela izquierda en la fibrilación auricular: una experiencia unicéntrica

BackgroundPercutaneous left atrial appendage closure (LAAC) has been proposed as an alternative to anticoagulation therapy in patients with nonvalvular atrial fibrillation to decrease the thromboembolic risk, while avoiding the risks of chronic anticoagulation. This option may be attractive in patients with nonvalvular atrial fibrillation and chronic kidney disease (CKD), since they exhibit both high-thromboembolic and bleeding risks.ObjectiveTo evaluate the prognostic impact of the presence of CKD in patients with atrial fibrillation undergoing LAAC peri-procedure and during the follow-up as compared with patients with preserved renal function.MethodsRetrospective, observational study that included 124 consecutive patients with atrial fibrillation undergoing LAAC in a university hospital, and the results were evaluated according to the baseline renal function of the patients.ResultsThe median age was 75.5 years (IQR 67.6–80) and 62.1% were men, the median of CHA₂DS₂-Vasc and HASBLED scores was 4 (IQR 3–4) for both scores. Up to 57.3% of the total sample had CKD. Baseline characteristics were similar between groups, but CKD patients were older and had a higher HASBLED score. During the procedure, no thromboembolic, bleeding events, or deaths were observed. Combining the time of hospitalization and follow-up, no significant differences were observed between groups in the annual rate of thromboembolic events (0.97/100 patient-years [100PY] vs. 4.06/100PY, p = .09), but there was a higher rate of bleeding events (5.67/100PY vs. 13.3/100PY, p = .033) and mortality among CKD patients (6.50/100PY vs. 17.2/100PY, p = .009), with an odds ratio of 2.711 (95% CI 1.96–6.95). In the multivariate analysis, a preserved eGFR was independently associated with a lower mortality risk.ConclusionsLAAC is a valid alternative to oral anticoagulation in patients with CKD and atrial fibrillation, with a low-rate of peri- and post-procedure complications, although CKD patients exhibited a higher risk of bleeding and mortality during the follow-up. However, these higher rates may not be necessarily related to the procedure.     

Etiopatogenia del prurito asociado a la enfermedad renal crónica: recomponiendo las piezas del puzle

Defined as the unpleasant sensation that causes the desire to scratch, pruritus is the most common skin symptom associated with uremia and appears in almost half of patients with advanced chronic kidney disease (CKD). Beyond its direct impact on quality of life, CKD-associated pruritus (CKD-aP) is an independent predictor of mortality that also has a synergistic effect with other quality of life-related symptoms, such as insomnia, depression, and anxiety. Although different mechanisms have been proposed to explain the origin of Pa-ERC, its etiopathogenesis is still not fully understood. Since new therapeutic targets have been identified and several clinical trials have recently shown promising results, our current understanding of the interrelationships has expanded significantly and the pathophysiological mechanisms underlying CKD-aP are now considered to be multifactorial. The potential triggers of pruritus in patients with CKD are discussed in this review, including hypotheses about skin xerosis, accumulation of uremic toxins, dysregulation of the immune system and systemic inflammation, uremic neuropathy, and imbalances in the endogenous opioid system. Other non-uremic causes of pruritus are also discussed, with the aim of guiding the physicians to apply an adequate etiopathogenic approach to CKD-aP in their day-to-day clinical practice.     

Interacción entre el estadio de la enfermedad renal crónica y la diabetes mellitus como factores asociados con mortalidad en pacientes con enfermedad renal crónica: un estudio de cohortes externas

IntroductionDiabetic kidney disease is the main cause of chronic kidney disease (CKD) worldwide. Both CKD and diabetes mellitus (DMT2) are important risk factors for mortality. However, it is still unknown if the risk of death is modified by the simultaneous presence of these diseases.ObjectiveTo evaluate the presence of an interaction between DMT2 and CKD for mortality in a representative population of a Latin American country.MethodsIt is an analytical cohort study of patients with CKD, who were followed for 4 years (between 2004 and 2009). We calculated the incidence rate, progression, survival (using Kaplan–Meier curves), interaction (on the additive and multiplicative scales) and impact of the different stages of CKD in patients with and without DMT2 (using a cox proportional hazards model).ResultsIn this population of 5663 individuals, both DMT2 and CKD are risk factors for mortality (P < 0.001). We found a statistically significant difference in mortality between individuals with and without DMT2, who also had CKD stages 3 – 4 – 5 (Log-rank P = 0.0076). Additionally, we found a statistically significant interaction for mortality in both the additive and multiplicative scales between DMT2 and CKD (P = 0.005). DMT2 was found to be a risk factor for mortality (Hazard Ratio 1.61 P < 0.001), but in individuals with DMT2, the only risks significantly associated with mortality, were age, dyslipidemia and nephroprotective drugs.ConclusiónThe interaction between CKD and DMT2 negatively modifies the risk of death of both diseases. This means that when the two diseases are present, the risk of mortality is lower than expected.     

Nuevos mecanismos implicados en el desarrollo de la enfermedad cardiovascular en la enfermedad renal crónica

Chronic kidney disease (CKD) is a pathology with a high worldwide incidence and an upward trend affecting the elderly. When CKD is very advanced, the use of renal replacement therapies is required to prolong its life (dialysis or kidney transplantation). Although dialysis improves many complications of CKD, the disease does not reverse completely. These patients present an increase in oxidative stress, chronic inflammation and the release of extracellular vesicles (EVs), which cause endothelial damage and the development of different cardiovascular diseases (CVD). CKD patients develop premature diseases associated with advanced age, such as CVD. EVs play an essential role in developing CVD in patients with CKD since their number increases in plasma and their content is modified. The EVs of patients with CKD cause endothelial dysfunction, senescence and vascular calcification. In addition, miRNAs free or transported in EVs together with other components carried in these EVs promote endothelial dysfunction, thrombotic and vascular calcification in CKD, among other effects. This review describes the classic factors and focuses on the role of new mechanisms involved in the development of CVD associated with CKD, emphasizing the role of EVs in the development of cardiovascular pathologies in the context of CKD. Moreover, the review summarized the EVs’ role as diagnostic and therapeutic tools, acting on EV release or content to avoid the development of CVD in CKD patients.