Executive summary of the KDIGO 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease

The Kidney Disease: Improving Global Outcomes (KDIGO) 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease for patients not receiving dialysis represents an update to the KDIGO 2012 guideline on this topic. Development of this guideline update followed a rigorous process of evidence review and appraisal. Guideline recommendations are based on systematic reviews of relevant studies and appraisal of the quality of the evidence. The strength of recommendations is based on the "Grading of Recommendations Assessment, Development and Evaluation" (GRADE) approach. The scope includes topics covered in the original guideline, such as optimal blood pressure targets, lifestyle interventions, antihypertensive medications, and specific management in kidney transplant recipients and children. Some aspects of general and cardiovascular health, such as lipid and smoking management, are excluded. This guideline also introduces a chapter dedicated to proper blood pressure measurement since all large randomized trials targeting blood pressure with pivotal outcomes used standardized preparation and measurement protocols adhered to by patients and clinicians. Based on previous and new evidence, in particular the Systolic Blood Pressure Intervention Trial (SPRINT) results, we propose a systolic blood pressure target of less than 120 mm Hg using standardized office reading for most people with chronic kidney disease (CKD) not receiving dialysis, the exception being children and kidney transplant recipients. The goal of this guideline is to provide clinicians and patients a useful resource with actionable recommendations supplemented with practice points. The burden of the recommendations on patients and resources, public policy implications, and limitations of the evidence are taken into consideration. Lastly, knowledge gaps and recommendations for future research are provided.

Executive summary of the KDIGO 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease.

The Kidney Disease: Improving Global Outcomes (KDIGO) 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease for patients not receiving dialysis represents an update to the KDIGO 2012 guideline on this topic. Development of this guideline update followed a rigorous process of evidence review and appraisal. Guideline recommendations are based on systematic reviews of relevant studies and appraisal of the quality of the evidence. The strength of recommendations is based on the "Grading of Recommendations Assessment, Development and Evaluation" (GRADE) approach. The scope includes topics covered in the original guideline, such as optimal blood pressure targets, lifestyle interventions, antihypertensive medications, and specific management in kidney transplant recipients and children. Some aspects of general and cardiovascular health, such as lipid and smoking management, are excluded. This guideline also introduces a chapter dedicated to proper blood pressure measurement since all large randomized trials targeting blood pressure with pivotal outcomes used standardized preparation and measurement protocols adhered to by patients and clinicians. Based on previous and new evidence, in particular the Systolic Blood Pressure Intervention Trial (SPRINT) results, we propose a systolic blood pressure target of less than 120 mm Hg using standardized office reading for most people with chronic kidney disease (CKD) not receiving dialysis, the exception being children and kidney transplant recipients. The goal of this guideline is to provide clinicians and patients a useful resource with actionable recommendations supplemented with practice points. The burden of the recommendations on patients and resources, public policy implications, and limitations of the evidence are taken into consideration. Lastly, knowledge gaps and recommendations for future research are provided.

Long-term effects of the iron-based phosphate binder, sucroferric oxyhydroxide, in dialysis patients.

BACKGROUND: Hyperphosphatemia necessitates the use of phosphate binders in most dialysis patients. Long-term efficacy and tolerability of the iron-based phosphate binder, sucroferric oxyhydroxide (previously known as PA21), was compared with that of sevelamer carbonate (sevelamer) in an open-label Phase III extension study. METHODS: In the initial Phase III study, hemo- or peritoneal dialysis patients with hyperphosphatemia were randomized 2:1 to receive sucroferric oxyhydroxide 1.0-3.0 g/day (2-6 tablets/day; n = 710) or sevelamer 2.4-14.4 g/day (3-18 tablets/day; n = 349) for 24 weeks. Eligible patients could enter the 28-week extension study, continuing the same treatment and dose they were receiving at the end of the initial study. RESULTS: Overall, 644 patients were available for efficacy analysis (n = 384 sucroferric oxyhydroxide; n = 260 sevelamer). Serum phosphorus concentrations were maintained during the extension study. Mean ± standard deviation (SD) change in serum phosphorus concentrations from extension study baseline to Week 52 end point was 0.02 ± 0.52 mmol/L with sucroferric oxyhydroxide and 0.09 ± 0.58 mmol/L with sevelamer. Mean serum phosphorus concentrations remained within Kidney Disease Outcomes Quality Initiative target range (1.13-1.78 mmol/L) for both treatment groups. Mean (SD) daily tablet number over the 28-week extension study was lower for sucroferric oxyhydroxide (4.0 ± 1.5) versus sevelamer (10.1 ± 6.6). Patient adherence was 86.2% with sucroferric oxyhydroxide versus 76.9% with sevelamer. Mean serum ferritin concentrations increased over the extension study in both treatment groups, but transferrin saturation (TSAT), iron and hemoglobin concentrations were generally stable. Gastrointestinal-related adverse events were similar and occurred early with both treatments, but decreased over time. CONCLUSIONS: The serum phosphorus-lowering effect of sucroferric oxyhydroxide was maintained over 1 year and associated with a lower pill burden, compared with sevelamer. Sucroferric oxyhydroxide was generally well tolerated long-term and there was no evidence of iron accumulation.

Research needs in the area of device-related treatments for hypertension.

Hypertension is the primary risk factor for cardiovascular and renal-disease endpoints. Medications help many patients but not all. Recently, two device-related treatments have been introduced, catheter-based renal denervation and electrical carotid sinus stimulation. Remuneration for these treatments is guaranteed in many countries even though basic information is missing. We draw attention to deficiencies in the database. For catheter-based renal denervation, few large-animal data are available to investigate the effect of the intervention on the histology of the arterial wall. No functional data are available regarding re-innervation. For carotid sinus stimulation, the situation is similar. Acute activation of either treatment seems to reduce sympathetic tone dramatically. However, whether or not the effects are sustained over time is unknown. No 'end-point' data are available for either treatment. Devices should be subjected to evidence-based standards before widespread introduction.

Phosphate additives in food--a health risk.

BACKGROUND: Hyperphosphatemia has been identified in the past decade as a strong predictor of mortality in advanced chronic kidney disease (CKD). For example, a study of patients in stage CKD 5 (with an annual mortality of about 20%) revealed that 12% of all deaths in this group were attributable to an elevated serum phosphate concentration. Recently, a high-normal serum phosphate concentration has also been found to be an independent predictor of cardiovascular events and mortality in the general population. Therefore, phosphate additives in food are a matter of concern, and their potential impact on health may well have been underappreciated. METHODS: We reviewed pertinent literature retrieved by a selective search of the PubMed and EU databases (www.zusatzstoffe-online.de, www.codexalimentarius.de), with the search terms "phosphate additives" and "hyperphosphatemia." RESULTS: There is no need to lower the content of natural phosphate, i.e. organic esters, in food, because this type of phosphate is incompletely absorbed; restricting its intake might even lead to protein malnutrition. On the other hand, inorganic phosphate in food additives is effectively absorbed and can measurably elevate the serum phosphate concentration in patients with advanced CKD. Foods with added phosphate tend to be eaten by persons at the lower end of the socioeconomic scale, who consume more processed and "fast" food. The main pathophysiological effect of phosphate is vascular damage, e.g. endothelial dysfunction and vascular calcification. Aside from the quality of phosphate in the diet (which also requires attention), the quantity of phosphate consumed by patients with advanced renal failure should not exceed 1000 mg per day, according to the guidelines. CONCLUSION: Prospective controlled trials are currently unavailable. In view of the high prevalence of CKD and the potential harm caused by phosphate additives to food, the public should be informed that added phosphate is damaging to health. Furthermore, calls for labeling the content of added phosphate in food are appropriate.

Effects of vitamin E on cardiovascular outcomes in people with mild-to-moderate renal insufficiency: results of the HOPE study.

BACKGROUND: A controlled trial reported cardiovascular benefits of vitamin E in terminal renal insufficiency. There are no data for renal insufficiency before the stage of terminal renal failure. We evaluated effects of vitamin E supplementation on cardiovascular and renal outcomes in 993 people with a serum creatinine > or =1.4 to 2.3 mg/dL. METHODS: Post-hoc analysis of a randomized trial that compared treatment with natural source vitamin E (400 IU/day) to placebo in 9541 people, 993 of which had renal insufficiency. Participants had either known cardiovascular disease or diabetes and at least one additional coronary risk factor. Exclusion criteria included a serum creatinine > 2.3 mg/dL and dipstick-positive proteinuria. The primary study outcome after an average of 4.5 years was the composite of myocardial infarction, stroke, or cardiovascular death. Secondary outcomes included revascularizations, total mortality, and clinical proteinuria. RESULTS: In renal insufficiency, vitamin E supplementation had a neutral effect on the primary study outcome, on each component of the composite primary outcome, and on all secondary outcomes. Two hundred twenty-four primary outcomes, 23% of the vitamin E group and 22.1% of the placebo group, relative risk 1.03 (95% CI, 0.79-1.34; P= 0.82), were observed, and 585 secondary outcomes, including death in 17% and 18.8% of the vitamin E and placebo groups, respectively (RR 0.88, 95% CI, 0.66-1.18; P= 0.40). There was no effect of vitamin E on progression of proteinuria. CONCLUSION: In people with mild-to-moderate renal insufficiency at high cardiovascular risk, vitamin E at a dose of 400 IU/day had no apparent effect on cardiovascular outcomes.

Effects of vitamin E on cardiovascular and microvascular outcomes in high-risk patients with diabetes: results of the HOPE study and MICRO-HOPE substudy.

OBJECTIVES: Experimental and observational studies suggest that vitamin E may reduce the risk of cardiovascular (CV) events and of microvascular complications in people with diabetes. However, data from randomized clinical trials are limited. Therefore, we evaluated the effects of vitamin E supplementation on major CV outcomes and on the development of nephropathy in people with diabetes. RESEARCH DESIGN AND METHODS: The Heart Outcomes Prevention Evaluation (HOPE) trial is a randomized clinical trial with a 2 x 2 factorial design, which evaluated the effects of vitamin E and of ramipril in patients at high risk for CV events. Patients were eligible for the study if they were 55 years or older and if they had CV disease or diabetes with at least one additional coronary risk factor. The study was designed to recruit a large number of people with diabetes, and the analyses of the effects of vitamin E in this group were preplanned. Patients were randomly allocated to daily treatment with 400 IU vitamin E and with 10 mg ramipril or their respective placebos and were followed for an average of 4.5 years. The primary study outcome was the composite of myocardial infarction, stroke, or CV death. Secondary outcomes included total mortality, hospitalizations for heart failure, hospitalizations for unstable angina, revascularizations, and overt nephropathy. RESULTS: There were 3,654 people with diabetes. Vitamin E had a neutral effect on the primary study outcome (relative risk = 1.03, 95% CI 0.88-1.21; P = 0.70), on each component of the composite primary outcome, and on all predefined secondary outcomes. CONCLUSIONS: The daily administration of 400 IU vitamin E for an average of 4.5 years to middle-aged and elderly people with diabetes and CV disease and/or additional coronary risk factor(s) has no effect on CV outcomes or nephropathy.