Effects of Sodium-Specific Medical Nutrition Therapy from a Registered Dietitian Nutritionist in Individuals with Chronic Kidney Disease: An Evidence Analysis Center Systematic Review and Meta-Analysis.

Dietary sodium intake can increase risk of hypertension, a leading cause of kidney failure in individuals with chronic kidney disease. The objective of this systematic review was to examine the effect of sodium-specific medical nutrition therapy provided by a registered dietitian nutritionist or international equivalent on blood pressure and urinary sodium excretion in individuals with chronic kidney disease, stages 2 through 5, receiving maintenance dialysis and posttransplant. Medline, the Cumulative Index to Nursing and Allied Health Literature, Cochrane Cochrane Central Register of Controlled Trials, and other databases were searched to identify eligible controlled trials published in the English language from January 2000 until June 2020 that addressed the research question. Risk of bias was assessed using the RoB 2.0 tool and quality of evidence was examined by outcome using the Grading of Recommendations Assessment, Development, and Evaluation method. Of the 5,642 articles identified, eight studies were included in the final analyses. Six studies targeted clients who were not dialyzed, including one with clients who were posttransplantation, and two studies with clients receiving maintenance hemodialysis. Sodium-specific medical nutrition therapy from a registered dietitian nutritionist significantly reduced clinic systolic blood pressure (mean difference -6.7, 95% CI -11.0 to -2.4 mm Hg; I2 = 51%) and diastolic blood pressure (mean difference -4.8, 95% CI, -7.1 to -2.4 mm Hg; I2 = 23%) as well as urinary sodium excretion (mean difference -67.6, 95% CI -91.6 to -43.6 mmol/day; I2 = 84.1%). Efficacy was limited to individuals who were not dialyzed, including posttransplantation, but the intervention did not significantly improve blood pressure in individuals receiving maintenance hemodialysis. Adults with chronic kidney disease should begin to work with registered dietitian nutritionist early in the course of disease to receive individualized, effective counseling to improve risk factors and, ultimately, health outcomes.

Despite increasing aldosterone, elevated potassium is not necessary for activating aldosterone-sensitive HSD2 neurons or sodium appetite.

Restricting dietary sodium promotes sodium appetite in rats. Prolonged sodium restriction increases plasma potassium (pK), and elevated pK is largely responsible for a concurrent increase in aldosterone, which helps promote sodium appetite. In addition to increasing aldosterone, we hypothesized that elevated potassium directly influences the brain to promote sodium appetite. To test this, we restricted dietary potassium in sodium-deprived rats. Potassium restriction reduced pK and blunted the increase in aldosterone caused by sodium deprivation, but did not prevent sodium appetite or the activation of aldosterone-sensitive HSD2 neurons. Conversely, supplementing potassium in sodium-deprived rats increased pK and aldosterone, but did not increase sodium appetite or the activation of HSD2 neurons relative to potassium restriction. Supplementing potassium without sodium deprivation did not significantly increase aldosterone and HSD2 neuronal activation and only modestly increased saline intake. Overall, restricting dietary sodium activated the HSD2 neurons and promoted sodium appetite across a wide range of pK and aldosterone, and saline consumption inactivated the HSD2 neurons despite persistent hyperaldosteronism. In conclusion, elevated potassium is important for increasing aldosterone, but it is neither necessary nor sufficient for activating HSD2 neurons and increasing sodium appetite.

A Systematic Review of Medical Nutrition Therapy Guidelines for Liver Cirrhosis: Do We Agree?

BACKGROUND: Nutrition can play a significant role in the management of liver cirrhosis and its complications. However, adherence to the clinical practice guidelines (CPGs) is essential for the practice of evidence-based medicine and is considered as a health-quality indicator. METHODS: A systematic search was conducted in scientific databases, and retrieved CPGs fulfilling the inclusion criteria were independently reviewed and appraised from 3 experienced researchers, based on the Appraisal of Guidelines for Research and Evaluation II instrument. RESULTS: A total of 13 relevant CPGs were retrieved, published by 7 associations/societies, focusing on the nutrition management (enteral nutrition and/or parenteral nutrition) on cirrhosis, decompensated cirrhosis, liver transplantation, and cirrhosis-related complications. Most CPGs scored low in the stakeholder, rigor of development, and applicability domains. Half of the CPGs recognized the need for counseling patients with cirrhosis on nutrition-related issues. Small meals spread throughout the day, including a late-night snack, were suggested, with protein intake ranging between 1.2 and 1.5 g/kg of body weight. In ascites, Na restriction recommendation appeared unanimous. CONCLUSIONS: Several shortcomings and bias were recognized in cirrhosis-related medical nutrition therapy CPGs, indicating the need of improving CPG methodology.

Understanding barriers to medication, dietary, and lifestyle treatments prescribed in polycystic kidney disease.

BACKGROUND: Autosomal dominant polycystic kidney disease (PKD) is the most common genetic renal disease and the fourth leading cause of end-stage renal disease in the United States. Although there is no cure for PKD, several treatments are considered to be beneficial, including blood pressure control, exercise, low-salt diet, and high volume water intake. However, levels of understanding of the importance of these treatments and adherence to these recommendations vary among patients. This study explores illness perception models of patients with PKD to reveal barriers in adherence to prescribed therapies; satisfaction with medical care; and sources of medical information. METHODS: We designed a phenomenological interview study to evaluate illness perception models of individuals with PKD. Patients were identified from the national PKD Foundation e-mail distribution list (N = 190) and responded voluntarily to an introductory survey (N = 50). Seventeen PKD patients in the Bay Area were scheduled for one-on-one in-depth interviews with one trained interviewer (W-CT). Open-ended questions administered with an interview guide were used to evaluate patients' beliefs. RESULTS: Mean age was 56.6 +/- 12 years (range 29-78); 65% were female. Many of the PKD patients in this study were highly motivated and willing to incorporate blood pressure, exercise, low-salt diet, and high volume water intake into their daily routines. Barriers to adherence to these therapies include personal beliefs and confusion due to unclear recommendations. CONCLUSIONS: These findings suggest there is variability between what patients understand about their disease and treatments and what they believe their doctors have told them. Not all physicians focus on lifestyle-based treatments, but the majority of PKD patients in our study are motivated and willing to incorporate blood pressure control, exercise, low-salt diet, and high volume water intake into their daily routines and would like specific recommendations on how to implement these. These findings support a role for further exploring patient beliefs about the disease and its necessary treatments in order to design strategies to improve communication and meet the needs of these patients.

Beyond Sodium, Phosphate and Potassium: Potential Dietary Interventions in Kidney Disease.

People with kidney disease are advised to restrict individual nutrients, such as sodium, potassium, and phosphate, in line with current best practice guidelines. However, there is limited evidence to support the efficacy of single nutrient strategies, and compliance remains a challenge for clinicians to overcome. Many factors contribute to poor compliance with dietary prescriptions, including conflicting priorities for single nutrient restriction, the arduous self-monitoring required, and the health-related knock-on effects resulting from targeting these nutrients in isolation. This paper reviews the evidence base for the overall pattern of eating as a potential tool to deliver a diet intervention in which all the nutrients and foods work cumulatively and synergistically to improve clinical outcomes. These interventions may assist in kidney disease management and overcome these innate challenges that single nutrient interventions possess. Healthy dietary patterns are typically plant-based and lower in sodium and animal proteins. These patterns may have numerous mechanistic benefits for cardiovascular health in kidney disease, most notably through the increase in fruit, vegetables, and plant-based protein, as well as improved gut health through the increase in dietary fiber. The evidence to date on optimal dietary patterns points toward use of a predominantly plant-based diet, and suggests its adoption may improve clinical outcomes in dialysis patients. However, clinical trials are needed to determine whether these diet interventions are feasible, safe, and effective in this patient population.

"Dietaly": practical issues for the nutritional management of CKD patients in Italy.

Evidence exists that nutritional therapy induces favorable metabolic changes, prevents signs and symptoms of renal insufficiency, and is able to delay the need of dialysis. Currently, the main concern of the renal diets has turned from the efficacy to the feasibility in the daily clinical practice.Herewith we describe some different dietary approaches, developed in Italy in the last decades and applied in the actual clinical practice for the nutritional management of CKD patients.A step-wise approach or simplified dietary regimens are usually prescribed while taking into account not only the residual renal function and progression rate but also socio-economic, psychological and functional aspects.The application of the principles of the Mediterranean diet that covers the recommended daily allowances for nutrients and protein (0.8 g/Kg/day) exert a favorable effect at least in the early stages of CKD. Low protein (0.6 g/kg/day) regimens that include vegan diet and very low-protein (0.3-0.4 g/Kg/day) diet supplemented with essential amino acids and ketoacids, represent more opportunities that should be tailored on the single patient's needs.Rather than a structured dietary plan, a list of basic recommendations to improve compliance with a low-sodium diet in CKD may allow patients to reach the desired salt target in the daily eating.Another approach consists of low protein diets as part of an integrated menu, in which patients can choose the "diet" that best suits their preferences and clinical needs.Lastly, in order to allow efficacy and safety, the importance of monitoring and follow up of a proper nutritional treatment in CKD patients is emphasized.

Salt in the diet in patients with heart failure: what to recommend.

PURPOSE OF REVIEW: Recognizing the relevance of sodium balance in heart failure, it has been presumed that patients with heart failure benefit from a low-sodium diet, though its efficacy and safety are unclear. The purpose of this review is to provide insight into the currently available evidence base for the effects of dietary sodium restriction in patients with chronic heart failure. RECENT FINDINGS: There has been an increasing body of evidence on the effects of sodium restriction in heart failure; however, both observational and experimental studies have shown mixed results. Recent randomized controlled trial data has even suggested that sodium restriction may have detrimental effects in patients with heart failure. Only a few randomized controlled trials have included clinical outcomes as a primary endpoint. These have been either unpowered to test the association between reduced sodium intake and outcomes, or conducted in the context of an aggressive diuretic treatment and fluid restriction. SUMMARY: The effects of a low-sodium diet on clinical outcomes in patients with heart failure remain unclear. Ongoing research into the effects of lowering sodium for patients with chronic or acute heart failure will shed light on the importance of holistic self-care and dietary strategies in heart failure.

Management of hypertension in CKD: beyond the guidelines.

Hypertension (HTN) and CKD are closely associated with an intermingled cause and effect relationship. Blood pressure (BP) typically rises with declines in kidney function, and sustained elevations in BP hasten progression of kidney disease. This review addresses current management issues in HTN in patients with CKD including altered circadian rhythm of BP, timing of antihypertensive medication dosing, BP targets, diagnostic challenges in evaluating secondary forms of HTN, and the role of salt restriction in CKD. HTN in patients with CKD is often accompanied by a decrease in the kidney's ability to remove salt. Addressing this salt sensitivity is critical for the management of HTN in CKD. In addition to the well-established use of an ACEI or angiotensin receptor blocker, dietary salt restriction and appropriate diuretic therapy make up the mainstay of HTN treatment in patients with CKD. Bedtime dosing of antihypertensive medications can restore nocturnal dips in BP, and future clinical practice guidelines may recommend bedtime dosing of 1 or more antihypertensive medications in patients with CKD.

Más allá del sodio: cambios en la dieta y su efecto en hipertensión / Beyond sodium: diet changes and their effect on hypertension

Resumen: La hipertensión arterial (HTA) es un importante factor de riesgo cardiovascular y su prevalencia aumenta con la edad, dado el aumento de la expectativa de vida de nuestra población esta condición constituye una prioridad a nivel de salud pública. Tanto para el tratamiento como para la prevención de la HTA son importantes las medidas no farmacológicas como cambios en el estilo de vida y especialmente la alimentación. Además de la restricción de sodio, existen otras medias dietéticas que han demostrado estar asociadas con un mejor control de la HTA en diversos ensayos clínicos, tales como la reducción del peso corporal, la dieta rica en frutas y verduras, el mayor consumo de potasio y magnesio, la vitamina D, los ácidos grasos ome-ga-3, los flavonoides y la disminución de la ingesta de sacarosa, fructosa, cafeína y alcohol. Dado la gran prevalencia de HTA en nuestro país del orden de un 26,9 por ciento, es importante dar a conocer medidas dietéticas que nos permitirán un mejor control de la presión en pacientes hipertensos y un retraso de la aparición de esta enfermedad en sujetos sanos, además de su incorporación en campañas de educación nutricional poblacional por parte de las autoridades sanitarias.

Hypertension is an important cardiovascular risk factor and its prevalence increases with age. Given the rising life expectancy in Chile, the prevention of hypertension is a priority for public health policies. Non pharmacological therapies, such as life style and diet changes are especially important. In addition to sodium restriction, several clinical studies have shown that other dietary interventions, such as an increased fruit and vegetable content of diet, higher intake of potassium and magnesium, vitamin D, omega-3 fatty acids, flavonoids, decreased intake of sucrose, fructose, caffeine and alcohol, lead to better control of hypertension. Given de high prevalence of hypertension in Chile (26.9 per cent overall) better information about the benefits of diet changes might be very important in order to help prevent and delay the appearance of hypertension. Appropriate public educational policies should be implemented by the sanitary authorities.

Beyond salt: lifestyle modifications and blood pressure.

Lifestyle changes have been shown to effect significant blood pressure (BP) reductions. Although there are several proposed neurohormonal links between weight loss and BP, body mass index itself appears to be the most powerful mediator of the weight-BP relationship. There appears to be a mostly linear relationship between weight and BP; as weight is regained, the BP benefit is mostly lost. Physical activity, but more so physical fitness (the physiological benefit obtained from physical activity), has a dose-dependent BP benefit but reaches a plateau at which there is no further benefit. However, even just a modest physical activity can have a meaningful BP effect. A diet rich in fruits and vegetables with low-fat dairy products and low in saturated and total fat (DASH) is independently effective in reducing BP. Of the dietary mineral nutrients, the strongest data exist for increased potassium intake, which reduces BP and stroke risk. Vitamin D is associated with BP benefit, but no causal relationship has been established. Flavonoids such as those found in cocoa and berries may have a modest BP benefit. Neither caffeine nor nicotine has any significant, lasting BP effect. Biofeedback therapies such as those obtained with device-guided breathing have a modest and safe BP benefit; more research is needed before such therapies move beyond those having an adjunctive treatment role. There is a strong, linear relationship between alcohol intake and BP; however, the alcohol effects on BP and coronary heart disease are divergent. The greatest BP benefit seems to be obtained with one drink per day for women and with two per day for men. This benefit is lost or attenuated if the drinking occurs in a binge form or without food. Overall, the greatest and most sustained BP benefit is obtained when multiple lifestyle interventions are incorporated simultaneously.

Apparent mineralocorticoid excess: time of manifestation and complications despite treatment.

Here we describe the case of a patient followed from birth because of a positive family history for apparent mineralocorticoid excess (AME) in an older brother. The patient, a girl, had normal serum electrolyte and blood pressure measurements in the first months after birth. Not until the age of 11 months did she develop anorexia and failure to thrive in combination with hypertension, hypokalemia, and metabolic alkalosis, which are consistent with the diagnosis of AME. This diagnosis was confirmed by mutation analysis of the HSD11B2 gene (C1228T). Treatment with amiloride and furosemide electrolyte disturbances normalized her blood pressure. At the age of 19 years she unexpectedly suffered a stroke. Additional investigations revealed no accepted risk factor for stroke. We discuss the possible underlying mechanisms for the delayed manifestation of hypertension and electrolyte disturbances in AME, propose an additional explanation for the stroke in this patient, and advise treatment with a mineralocorticoid receptor antagonist to reduce stroke risk in patients with AME.

Hypertension: salt restriction, sodium homeostasis, and other ions.

Salt is composed of Sodium Chloride (NaCl) which in body water becomes essential electrolytes, viz., Sodium (Na⁺) and Chloride (Cl⁻) ions, including in the blood and other extracellular fluids (ECF). Na⁺ ions are necessary cations in muscle contractions and their depletion will effect all the muscles in body including smooth muscle contraction of blood vessels, a fact which is utilized in lowering the blood pressure. Na⁺ ions also hold water with them in the ECF. Na⁺ homeostasis in body is maintained by thirst (water intake), kidneys (urinary excretion) and skin (sweating). In Na⁺ withdrawal, body tries to maintain homeostasis as far as possible. However, in certain conditions (e.g., during exercise, intake of drugs and in disorders causing Syndrome of Inappropriate Anti Diuretic Hormone Secretion (SIADH), diuretics, diarrhea) coupled with moderate or severe dietary salt restriction (anorexia nervosa), hyponatremia can get precipitated. Hyponatremia is one end point in the spectrum of disorders caused by severe Na⁺ depletion whereas in moderate depletion it can cause hypohydration (or less total body water) and lower urinary volume (U v ). Moreover, salt sensitivity varies in various populations leading to different responses in relation to dietary Na⁺ intake. Diabetes and Hypertension often co-exist but Na⁺ withdrawal in salt sensitive subjects worsens diabetes though hypertension gets better and reverse occurs in salt loading. Therefore, Na⁺ or salt restriction may be non-physiological. In hypertensive subjects other alternatives to Na⁺ withdrawal could be Potassium (K⁺) and Calcium (Ca⁺²) supplementation. Further studies are required to monitor safety/side effects of salt restriction.

Development and evaluation of DASH diet tailored messages for hypertension treatment.

For this study, the Manage Associated Perceptions (MAP) of Dietary Behavior Study, researchers developed, evaluated, and tested messages tailored to improve compliance with the Dietary Approaches to Stop Hypertension (DASH) diet by gradually instilling healthy Cognitive Representations of the DASH Diet (CRDDs). The sample consisted of women from diverse backgrounds (N = 53), randomly assigned to two experimental groups (n = 13 and n = 14) and to two control groups (n = 12 and n = 14). The experimental groups performed a version of the intervention for 30 days. Data about dietary compliance and CRDDs were collected at 30, 60, and 90 days. Compared to control group members, experimental group members demonstrated greater improvements in CRDD scores and were significantly more compliant with the diet. Another significant finding was that older women were more compliant.

Should we restrict chloride rather than sodium?

Low-salt diets have potential for prevention and treatment of hypertension, and may also reduce risk for stroke, left ventricular hypertrophy, osteoporosis, renal stones, asthma, cataract, gastric pathology, and possibly even senile dementia. Nonetheless, the fact that salt restriction evokes certain counter-regulatory metabolic responses-- increased production of renin and angiotensin II, as well as increased sympathetic activity--that are potentially inimical to vascular health, has suggested to some observers that salt restriction might not be of unalloyed benefit, and might in fact be contraindicated in some "salt-resistant" subjects. Current epidemiology indicates that lower-salt diets tend to reduce coronary risk quite markedly in obese subjects, whereas the impact of such diets on leaner subjects (who are less likely to be salt sensitive) is equivocal--seemingly consistent with the possibility that salt restriction can exert countervailing effects on vascular health. There is considerable evidence that sodium chloride, rather than sodium per se, is responsible for the known adverse effects of dietary salt. Other non-halide sodium salts, such as sodium citrate or bicarbonate, do not raise plasma volume, increase blood pressure, boost urinary calcium loss, or promote stroke in stroke-prone rats. Nonetheless, these compounds have been shown to blunt the impact of salt restriction on renin, angiotensin II, and sympathetic activity in humans. This may rationalize limited clinical evidence that organic sodium salts can decrease blood pressure in salt-restricted hypertensives. Furthermore, organic sodium salts have an alkalinizing metabolic impact favorable to bone health. These considerations suggest that restricting dietary salt to the extent feasible, while encouraging consumption of organic sodium salts in mineral waters, soft drinks, or other nutraceuticals--preferably in conjunction with organic potassium salts and taurine--may represent a superior strategy for controlling blood pressure, promoting vascular health, and preserving bone density. Further clinical studies should determine whether a moderately salt-restricted diet supplemented with organic sodium salts has a better and more uniform impact on hypertension than salt restriction alone, while rodent studies should examine the comparative impact of these regimens on rodents prone to vascular disease.