Considerable international variation exists in blood pressure control and antihypertensive prescription patterns in chronic kidney disease

Antihypertensive Treatment Patterns in CKD Stages 3 and 4: The CKD-REIN Cohort Study

Rationale & Objective

Blood pressure (BP) control is essential for preventing cardiorenal complications in chronic kidney disease (CKD), but most patients fail to reach BP target. We assessed longitudinal patterns of antihypertensive drug prescription and systolic BP.

Study Design

Prospective observational cohort study.

Setting & Population

In total, 2,755 hypertensive patients with CKD stages 3-4, receiving care from a nephrologist, from the French CKD-Renal Epidemiology and Information Network (CKD-REIN cohort study).

Exposure

Patient factors, including sociodemographic characteristics, medical history, and laboratory data, and provider factors, including number of primary care physician and specialist encounters.

Outcomes

Changes in antihypertensive drug-class prescription during follow-up: add-on or withdrawal.

Analytical Approach

Hierarchical shared-frailty models to estimate hazard ratios (HR) to deal with clustering at the nephrologist level and linear mixed models to describe systolic BP trajectory.

Results

At baseline, median age was 69 years, and mean estimated glomerular filtration rate was 33 mL/min/1.73 m². In total, 66% of patients were men, 81% had BP ≥ 130/80 mm Hg, and 75% were prescribed ≥2 antihypertensive drugs. During a median 5-year follow-up, the rate of changes of antihypertensive prescription was 50 per 100 person-years, 23 per 100 for add-ons, and 25 per 100 for withdrawals. After adjusting for risk factors, systolic BP, and the number of antihypertensive drugs, poor medication adherence was associated with increased HR for add-on (1.35, 95% confidence interval [CI], 1.01-1.80), whereas a lower education level was associated with increased HR for withdrawal (1.23, 95% CI, 1.02-1.49) for 9-11 years versus ≥12 years. More frequent nephrologist visits (≥4 vs none) were associated with higher HRs of add-on and withdrawal (1.52, 95% CI, 1.06-2.18; 1.57, 95% CI, 1.12-2.19, respectively), whereas associations with visit frequency to other physicians varied with their specialty. Mean systolic BP decreased by 4 mm Hg following drug add-on but tended to increase thereafter.

Limitations

Lack of information on prescriber and drug dosing.

Conclusions

In patients with CKD and poor BP control, changes in antihypertensive drug prescriptions are common and relate to clinician preferences and patients' tolerability. Sustainable reduction in systolic BP after add-on of a drug class is infrequently achieved.

A review of the latest real-world evidence studies in diabetic kidney disease: What have we learned about clinical practice and the clinical effectiveness of interventions?

Diabetic nephropathy, also known as diabetic kidney disease (DKD), remains a challenge in clinical practice as this is the major cause of kidney failure worldwide. Clinical trials do not answer all the questions raised in clinical practice and real-world evidence provides complementary insights from randomized controlled trials. Real-life longitudinal data highlight the need for improved screening and management of diabetic nephropathy in primary care. Adherence to the recommended guidelines for comprehensive care appears to be suboptimal in clinical practice in patients with DKD. Barriers to the initiation of sodium-glucose cotransporter-2 (SGLT2) inhibitors for patients with DKD persist in clinical practice, in particular for the elderly. Attainment of blood pressure targets often remains an issue. Initiation of glucagon-like peptide-1 receptor agonists (GLP-1RAs) in routine clinical practice is associated with a reduced risk of albuminuria progression and a possible beneficial effect on kidney function. Real-world evidence confirms a beneficial effect of SGLT2 inhibitors on the decline of glomerular filtration, even in the absence of albuminuria, with a lower risk of acute kidney injury events compared to GLP-1RA use. In addition, SGLT2 inhibitors confer a lower risk of hyperkalaemia after initiation compared with dipeptidyl peptidase-4 inhibitors in patients with DKD. Data from a large population indicate that diuretic treatment increases the risk of a significant decline in glomerular filtration rate in the first few weeks of treatment after SGLT2 inhibitor initiation. The perspective for a global approach targeting multifaceted criteria for diabetic individuals with DKD is emerging based on real-world evidence but there is still a long way to go to achieve this goal.

Optimizing kidney and cardiovascular protection in an era of multiple effective treatments

PURPOSE OF REVIEW

After decades of relying on the control of hypertension and treatment with renin angiotensin system inhibitors as the only evidence-based interventions to slow the progression of chronic kidney disease (CKD), we have entered an era when multiple effective treatment options are available. This review considers the mechanisms and benefits of these novel treatments as well as the challenges associated with achieving optimal combination therapy.

RECENT FINDINGS

Over the past 5 years, large clinical trials have provided robust evidence that, when added to renin angiotensin system inhibitors, treatment with sodium glucose cotransporter 2 inhibitors reduces the rate of CKD progression and the risk of cardiovascular events in people with CKD with or without diabetes and with or without albuminuria; nonsteroidal mineralocorticoid antagonists and glucagon-like peptide-1 receptor agonists afford similar benefits in people with type 2 diabetes and CKD. The mechanisms of actions of these novel therapies suggest that combination therapy will produce additive benefits, though specific evidence is sparse.

SUMMARY

Further trials are warranted to investigate the benefits of combination therapy with novel treatments in people with CKD. Clinical implementation of optimal combination therapy will require reorganization of services to ensure that patients receive adequate education, support and monitoring.

Clinical Outcomes in Patients with CKD and Rapid or Non-rapid eGFR Decline: A Report from the DISCOVER CKD Retrospective Cohort

INTRODUCTION

This analysis examined the baseline characteristics and clinical outcomes of patients with chronic kidney disease (CKD) and rapid or non-rapid estimated glomerular filtration rate (eGFR) decline, using retrospective data from DISCOVER CKD (ClinicalTrials.gov, NCT04034992).

METHODS

Data (2008-2020) were extracted from UK Clinical Practice Research Datalink, US TriNetX, US Limited Claims and Electronic Health Record Dataset, and Japan Medical Data Vision. Patients with CKD (two consecutive eGFR measures < 75 mL/min/1.73 m2 recorded 90-730 days apart) were included. Rapid eGFR decline was defined as an annual decline of > 4 mL/min/1.73 m2 at 2 years post-index; non-rapid eGFR decline was defined as an annual decline of ≤ 4 mL/min/1.73 m2. Clinical outcomes assessed included all-cause mortality, kidney outcomes (composite risk of kidney failure [progression to CKD stage 5] or > 50% eGFR decline, and kidney failure alone), cardiovascular events-including major adverse cardiovascular events (MACE; non-fatal myocardial infarction/stroke and cardiovascular death)-and all-cause hospitalization.

RESULTS

Across databases, rapid eGFR decline occurred in 13.7% of 804,237 eligible patients. Mean annual eGFR decline ranged between - 6.21 and - 6.86 mL/min/1.73 m2 in patients with rapid eGFR decline versus between - 0.11 and - 0.77 mL/min/1.73 m2 in patients with non-rapid eGFR decline. Rapid eGFR decline was associated with increased comorbidity burden and medication prescriptions. Across databases, the composite risk of kidney failure or > 50% decline in eGFR was significantly greater in patients with rapid versus non-rapid eGFR decline (P < 0.01); all-cause mortality, kidney failure alone, MACE, and all-cause hospitalization each significantly increased in two databases (P < 0.01-0.05).

CONCLUSION

Understanding patient factors associated with rapid eGFR decline in patients with CKD may help identify individuals who would benefit from proactive management to minimize the risk of adverse outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT04034992.

Managing cardiovascular risk factors in patients with chronic kidney disease: pharmacological and non-pharmacological interventions in the Copenhagen CKD Cohort

Background

Although cardiovascular morbidity and mortality are substantial in patients with chronic kidney disease (CKD), guideline-directed treatment of cardiovascular risk factors remains a challenge.

Methods

Observational, cross-sectional study including patients aged 30-75 years with CKD stage 1-5 without kidney replacement therapy from a tertiary hospital outpatient clinic. Data were obtained through patient interview, clinical examination, biochemical work-up, and evaluation of medical records and prescription redemptions. Guideline-directed treatment was evaluated as pharmacological interventions: antihypertensive and lipid-lowering therapy including adverse effects and adherence estimated as medication possession ratio (MPR); and non-pharmacological interventions: smoking status, alcohol consumption, body mass index (BMI), and physical activity.

Results

The cohort comprised 741 patients, mean age 58 years, 61.4% male, 50.6% CKD stage 3, 61.0% office blood pressure ≤140/90 mmHg. Antihypertensives were prescribed to 87.0%, median number of medications 2 (IQR 1;3), 70.1% received renin-angiotensin system inhibition, 25.9% reported adverse effects. Non-adherence (MPR < 80%) was present in 23.4% and associated with elevated blood pressure (OR 1.53 (95% CI 1.03;2.27)) and increased urinary albumin excretion, P < 0.001. Lipid-lowering treatment was prescribed to 54.0% of eligible patients, 11.1% reported adverse effects, and 28.5% were non-adherent, which was associated with higher LDL cholesterol, P = 0.036. Overall, 19.2% were current smokers, 16.7% overconsumed alcohol according to Danish health authority recommendations 69.3% had BMI ≥ 25 kg/m2, and 38.3% were physically active <4 hours/week. Among patients prescribed antihypertensives, 51.9% reported having received advice on non-pharmacological interventions.

Conclusions

Improved management of cardiovascular risk in patients with CKD entails intensified medical treatment and increased focus on patient adherence and non-pharmacological interventions.

Renin-angiotensin system inhibitors prescriptions in Chinese hospitalized chronic kidney disease patients

BACKGROUND

Many guidelines have recommended renin-angiotensin system inhibitors (RASI) as the first-line treatment for patients with chronic kidney disease (CKD). We studied RASI prescription trends from 2010 to 2019, and analyzed the characteristics associated with RASI prescription in Chinese hospitalized CKD patients.

AIM

To study the prescription of renin angiotensin system inhibitors in hospitalized patients with CKD in China.

METHODS

It was retrospectively, cross-sectional reviewed RASI prescriptions in hospitalized CKD patients in China from 2010 to 2019. RASI prescribing trends were analyzed from 2010 to 2019, and bivariate and multivariate logistic regression analyses were conducted to identify characteristics associated with RASI prescription.

RESULTS

A total of 35090 CKD patients were included, with 10043 (28.6%) RASI prescriptions. Among these patients, 18919 (53.9%) met the criteria for RASI treatments based on the 2012 kidney disease: Improving global outcomes guidelines. Of these, 7246 (38.3%) patients received RASI prescriptions. RASI prescriptions showed an initial rapid increase from 2011 to 2012, reached its peak around 2015 and 2016, and then exhibited a subsequent slight decreasing trend. Both bivariate and multivariate analyses showed that several characteristics, including the male gender, age less than 60-year-old, nephrology department admission, lower CKD stage, history of hypertension or diabetes, proteinuria, glomerulonephritis as the CKD etiology, and non-acute kidney injury were associated with RASI prescriptions.

CONCLUSION

The frequency of RASI prescriptions showed an initial increase but a slight decreasing trend in more recent years. CKD patients with certain characteristics such as elderly age, advanced disease stage, surgery department admission, or acute kidney injury were less likely to receive RASI prescriptions. In the application of RASI in hospitalized CKD patients is insufficient. The actual clinical practice needs to be improved. The development of related research is helpful to guide the correct choice of clinical treatment strategy.

Trends of Antihypertensive Prescription Among US Adults From 2010 to 2019 and Changes Following Treatment Guidelines: Analysis of Multicenter Electronic Health Records

BACKGROUND

Guidelines for the use of antihypertensives changed in 2014 and 2017. To understand the effect of these guidelines, we examined trends in antihypertensive prescriptions in the United States from 2010 to 2019 using a repeated cross-sectional design.

METHODS AND RESULTS

Using electronic health records from 15 health care institutions for adults (20-85 years old) who had ≥1 antihypertensive prescription, we assessed whether (1) prescriptions of beta blockers decreased after the 2014 Eighth Joint National Committee (JNC 8) report discouraged use for first-line treatment, (2) prescriptions for calcium channel blockers and thiazide diuretics increased among Black patients after the JNC 8 report encouraged use as first-line therapy, and (3) prescriptions for dual therapy and fixed-dose combination among patients with blood pressure ≥140/90 mm Hg increased after recommendations in the 2017 Hypertension Clinical Practice Guidelines. The study included 1 074 314 patients with 2 133 158 prescription episodes. After publication of the JNC 8 report, prescriptions for beta blockers decreased (3% lower in 2018-2019 compared to 2010-2014), and calcium channel blockers increased among Black patients (20% higher in 2015-2017 and 41% higher in 2018-2019, compared to 2010-2014), in accordance with guideline recommendations. However, contrary to guidelines, dual therapy and fixed-dose combination decreased after publication of the 2017 Hypertension Clinical Practice Guidelines (9% and 11% decrease in 2018-2019 for dual therapy and fixed-dose combination, respectively, compared to 2015-2017), and thiazide diuretics decreased among Black patients after the JNC 8 report (6% lower in 2018-2019 compared to 2010-2014).

CONCLUSIONS

Adherence to guidelines on prescribing antihypertensive medication was inconsistent, presenting an opportunity for interventions to achieve better blood pressure control in the US population.

The number of nephroprotection targets attained is associated with cardiorenal outcomes and mortality in patients with diabetic kidney disease. The CKD-REIN cohort study

AIM

The risk of cardiorenal events remains high among patients with diabetes and chronic kidney disease (CKD), despite the prescription of recommended treatments. We aimed to determine whether the attainment of a combination of nephroprotection targets at baseline (glycated haemoglobin <7.0%, urinary albumin-creatinine ratio <300 mg/g, blood pressure <130/80 mmHg, renin-angiotensin system inhibition) was associated with better cardiorenal outcomes and lower mortality.

MATERIALS AND METHODS

From the prospective French CKD-REIN cohort, we studied 1260 patients with diabetes and CKD stages 3-4 (estimated glomerular filtration rate: 15-60 ml/min/1.73 m2); 69% were men, and at inclusion, mean ± SD age: 70 ± 10 years; estimated glomerular filtration rate: 33 ± 11 ml/min/1.73 m2. The median follow-up was 4.9 years.

RESULTS

In adjusted Cox regression models, the attainment of two nephroprotection targets was consistently associated with a lower risk of cardiorenal events [hazard ratio 0.70 (95% confidence interval 0.57-0.85)], incident kidney failure with replacement therapy [0.58 (0.43-0.77)], four major adverse cardiovascular events (cardiovascular death, myocardial infarction, stroke, hospitalization for heart failure) [0.75 (0.57-0.99)] and all-cause mortality [0.59 (0.42-0.82)] when compared with the attainment of zero or one target. For patients with a urinary albumin-creatinine ratio ≥300 mg/g, those who attained at least two targets had lower hazard ratios for cardiorenal events [0.61 (0.39-0.96)], four major adverse cardiovascular events [0.53 (0.28-0.98)] and all-cause mortality [0.35 (0.17-0.70)] compared with those who failed to attain any targets.

CONCLUSIONS

These findings suggest that the attainment of a combination of nephroprotection targets is associated with better cardiorenal outcomes and a lower mortality rate in people with diabetic kidney disease.

Dapagliflozin and Blood Pressure in Patients with Chronic Kidney Disease and Albuminuria

BACKGROUND AND AIMS

Sodium-glucose cotransporter 2 inhibitors decrease blood pressure in patients with type 2 diabetes, but the consistency and magnitude of blood pressure lowering with dapagliflozin in patients with chronic kidney disease (CKD) is unknown. We conducted a prespecified analysis of the DAPA-CKD trial to investigate the effect of dapagliflozin on systolic blood pressure (SBP) in patients with CKD, with and without type 2 diabetes.

METHODS

A total of 4304 adults with baseline estimated glomerular filtration rate (eGFR) 25-75 mL/min/1.73m2 and urinary albumin-to-creatinine ratio (UACR) 200-5000 mg/g were randomized to either dapagliflozin 10 mg or placebo once daily; median follow-up was 2.4 years. The primary endpoint was a composite of sustained ≥50% eGFR decline, end-stage kidney disease, or death from a kidney or cardiovascular cause. Change in SBP was a prespecified outcome.

RESULTS

Baseline mean (SD) SBP was 137.1 mmHg (17.4). By Week 2, dapagliflozin compared to placebo reduced SBP by 3.6 mmHg (95% CI 2.8-4.4 mmHg), an effect maintained over the duration of the trial (2.9 mmHg, 2.3-3.6 mmHg). Time-averaged reductions in SBP were 3.2 mmHg (2.5-4.0 mmHg) in patients with diabetes and 2.3 mmHg (1.2-3.4 mmHg) in patients without diabetes. The time-averaged effect of dapagliflozin on diastolic blood pressure (DBP) was 1.0 mmHg (0.6-1.4 mmHg); 0.8 mmHg (0.4-1.3 mmHg) in patients with diabetes and 1.4 mmHg (0.7-2.1 mmHg) in patients without diabetes. Benefits of dapagliflozin on the primary composite and secondary endpoints were evident across the spectrum of baseline SBP and DBP.

CONCLUSION

In patients with CKD and albuminuria, randomization to dapagliflozin was associated with modest reductions in systolic and diastolic BP.

Relationship between urinary potassium excretion, serum potassium levels and cardiac injury in non-dialysis chronic kidney disease: KoreaN cohort study for Outcome in patients With Chronic Kidney Disease (KNOW-CKD)

Although the cardiovascular benefits of an increased urinary potassium excretion have been suggested, little is known about the potential cardiac association of urinary potassium excretion in patients with chronic kidney disease. In addition, whether the cardiac association of urinary potassium excretion was mediated by serum potassium levels has not been studied yet. We reviewed the data of 1633 patients from a large-scale multicentre prospective Korean study (2011-2016). Spot urinary potassium to creatinine ratio was used as a surrogate for urinary potassium excretion. Cardiac injury was defined as a high-sensitivity troponin T ≥ 14 ng/l. OR and 95 % (CI for cardiac injury were calculated using logistic regression analyses. Of 1633 patients, the mean spot urinary potassium to creatinine ratio was 49·5 (sd 22·6) mmol/g Cr and the overall prevalence of cardiac injury was 33·9 %. Although serum potassium levels were not associated with cardiac injury, per 10 mmol/g Cr increase in the spot urinary potassium to creatinine ratio was associated with decreased odds of cardiac injury: OR 0·917 (95 % CI 0·841, 0·998), P = 0·047) in multivariate logistic regression analysis. In mediation analysis, approximately 6·4 % of the relationship between spot urinary potassium to creatinine ratio and cardiac injury was mediated by serum potassium levels, which was not statistically significant (P = 0·368). Higher urinary potassium excretion was associated with lower odds of cardiac injury, which was not mediated by serum potassium levels.

Alcohol Consumption and Antihypertensive Treatment Effect in Male Patients With Hypertension

BACKGROUND

Alcohol consumption is a proven risk factor of hypertension. In the present analysis, we investigated the use of antihypertensive medications and blood pressure control in male alcohol drinkers and non-drinkers with hypertension (systolic/diastolic blood pressure 160-199/100-119 mm Hg).

METHODS

The study participants were patients enrolled in a 12-week therapeutic study and treated with the irbesartan/hydrochlorothiazide combination 150/12.5 mg once daily, with the possible up-titration to 300/12.5 mg/day and 300/25 mg/day at 4 and 8 weeks of follow-up, respectively, for blood pressure control of <140/90 mm Hg or <130/80 mm Hg in patients with diabetes mellitus. Alcohol consumption was classified as non-drinkers and drinkers.

RESULTS

The 68 alcohol drinkers and 168 non-drinkers had similar systolic/diastolic blood pressure at baseline (160.8 ± 12.1/99.8 ± 8.6 vs. 161.8 ± 11.0/99.2 ± 8.6, P ≥ 0.55) and other characteristics except for current smoking (80.9% vs. 47.6%, P < 0.0001). In patients who completed the 12-week follow-up (n = 215), the use of higher dosages of antihypertensive drugs was similar at 4 weeks of follow-up in drinkers and non-drinkers (10.6% vs. 12.4%, P = 0.70), but increased to a significantly higher proportion in drinkers than non-drinkers at 12 weeks of follow-up (54.7% vs. 36.6%, P = 0.01). The control rate of hypertension tended to be lower in alcohol drinkers, compared with non-drinkers, at 4 weeks of follow-up (45.6% vs. 58.9%, P = 0.06), but became similar at 12 weeks of follow-up (51.5% vs. 54.8%, P = 0.65).

CONCLUSION

Alcohol drinkers compared with non-drinkers required a higher dosage of antihypertensive drug treatment to achieve similar blood pressure control.

CLINICAL TRIAL REGISTRY NUMBER

NCT00670566 at www.clinicaltrials.gov.

Antihypertensive prescribing patterns in non-dialysis dependent chronic kidney disease: Findings from the Salford Kidney Study

BACKGROUND

Hypertension is commonly observed in patients living with chronic kidney disease (CKD). Finding an optimal treatment regime remains challenging due to the complex bidirectional cause-and-effect relationship between hypertension and CKD. There remains variability in antihypertensive treatment practices.

AIM

To analyze data from the Salford Kidney Study database in relation to antihypertensive prescribing patterns amongst CKD patients.

METHODS

The Salford Kidney Study is an ongoing prospective study that has been recruiting CKD patients since 2002. All patients are followed up annually, and their medical records including the list of medications are updated until they reach study endpoints [starting on renal replacement therapy or reaching estimated glomerular filtration rate (eGFR) expressed as mL/min/1.73 m2 ≤ 10 mL/min/1.73 m2, or the last follow-up date, or data lock on December 31, 2021, or death]. Data on antihypertensive prescription practices in correspondence to baseline eGFR, urine albumin-creatinine ratio, primary CKD aetiology, and cardiovascular disease were evaluated. Associations between patients who were prescribed three or more antihypertensive agents and their clinical outcomes were studied by Cox regression analysis. Kaplan-Meier analysis demonstrated differences in survival probabilities.

RESULTS

Three thousand two hundred and thirty non-dialysis-dependent CKD patients with data collected between October 2002 and December 2019 were included. The median age was 65 years. A greater proportion of patients were taking three or more antihypertensive agents with advancing CKD stages (53% of eGFR ≤ 15 mL/min/1.73 m2 vs 26% of eGFR ≥ 60 mL/min/1.73 m2, P < 0.001). An increased number of patients receiving more classes of antihypertensive agents was observed as the urine albumin-creatinine ratio category increased (category A3: 62% vs category A1: 40%, P < 0.001), with the upward trends particularly noticeable in the number of individuals prescribed renin angiotensin system blockers. The prescription of three or more antihypertensive agents was associated with all-cause mortality, independent of blood pressure control (hazard ratio: 1.15; 95% confidence interval: 1.04-1.27, P = 0.006). Kaplan-Meier analysis illustrated significant differences in survival outcomes between patients with three or more and those with less than three antihypertensive agents prescribed (log-rank, P < 0.001).

CONCLUSION

Antihypertensive prescribing patterns in the Salford Kidney Study based on CKD stage were consistent with expectations from the current United Kingdom National Institute of Health and Care Excellence guideline algorithm. Outcomes were poorer in patients with poor blood pressure control despite being on multiple antihypertensive agents. Continued research is required to bridge remaining variations in hypertension treatment practices worldwide.

Hypertension in chronic kidney disease-treatment standard 2023

Hypertension is very common and remains often poorly controlled in patients with chronic kidney disease (CKD). Accurate blood pressure (BP) measurement is the essential first step in the diagnosis and management of hypertension. Dietary sodium restriction is often overlooked, but can improve BP control, especially among patients treated with an agent to block the renin-angiotensin system. In the presence of very high albuminuria, international guidelines consistently and strongly recommend the use of an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker as the antihypertensive agent of first choice. Long-acting dihydropyridine calcium channel blockers and diuretics are reasonable second- and third-line therapeutic options. For patients with treatment-resistant hypertension, guidelines recommend the addition of spironolactone to the baseline antihypertensive regimen. However, the associated risk of hyperkalemia restricts the broad utilization of spironolactone in patients with moderate-to-advanced CKD. Evidence from the CLICK (Chlorthalidone in Chronic Kidney Disease) trial indicates that the thiazide-like diuretic chlorthalidone is effective and serves as an alternative therapeutic opportunity for patients with stage 4 CKD and uncontrolled hypertension, including those with treatment-resistant hypertension. Chlorthalidone can also mitigate the risk of hyperkalemia to enable the concomitant use of spironolactone, but this combination requires careful monitoring of BP and kidney function for the prevention of adverse events. Emerging agents, such as the non-steroidal mineralocorticoid receptor antagonist ocedurenone, dual endothelin receptor antagonist aprocitentan and the aldosterone synthase inhibitor baxdrostat offer novel targets and strategies to control BP better. Larger and longer term clinical trials are needed to demonstrate the safety and efficacy of these novel therapies in the future. In this article, we review the current standards of treatment and discuss novel developments in pathophysiology, diagnosis, outcome prediction and management of hypertension in patients with CKD.

Blood pressure targets in chronic kidney disease: still no consensus

PURPOSE OF REVIEW

Despite a strong consensus that treatment of hypertension is fundamental to strategies seeking to slow chronic kidney disease (CKD) progression and reduce the associated risk of cardiovascular events (CVE), controversy persists regarding optimal blood pressure (BP) targets. This article reviews the evidence for different targets, discusses associated controversies and suggests approaches to improve BP control.

RECENT FINDINGS

Landmark clinical trials established the principle that lower BP targets are associated with slower progression of CKD in people with a greater magnitude of proteinuria and previous guidelines recommended a target BP of <130/80 mmHg for those with proteinuria. However, the Systolic Blood Pressure Intervention Trial provided new evidence that a systolic BP target of <120 mmHg was associated with a reduced risk of CVE, though there was no impact on CKD progression and there was concern about an increase in renal adverse events. Nevertheless, 2021 Kidney Disease Improving Global Outcomes guidelines recommended systolic BP <120 mmHg, though other updated guidelines did not follow this trend. All guidelines emphasise the importance of standardised BP measurement and a personalised approach.

SUMMARY

An individualised and shared decision-making approach to BP target setting and management is recommended, guided by standardised BP measurement.

Associations with age and glomerular filtration rate in a referred population with chronic kidney disease: methods and baseline data from a UK multicentre cohort study (NURTuRE-CKD)

BACKGROUND

Chronic kidney disease (CKD) is common but heterogenous and is associated with multiple adverse outcomes. The National Unified Renal Translational Research Enterprise (NURTuRE)-CKD cohort was established to investigate risk factors for clinically important outcomes in persons with CKD referred to secondary care.

METHODS

Eligible participants with CKD stages G3-4 or stages G1-2 plus albuminuria >30 mg/mmol were enrolled from 16 nephrology centres in England, Scotland and Wales from 2017 to 2019. Baseline assessment included demographic data, routine laboratory data and research samples. Clinical outcomes are being collected over 15 years by the UK Renal Registry using established data linkage. Baseline data are presented with subgroup analysis by age, sex and estimated glomerular filtration rate (eGFR).

RESULTS

A total of 2996 participants was enrolled. Median (interquartile range) age was 66 (54-74) years, eGFR 33.8 (24.0-46.6) mL/min/1.73 m2 and urine albumin to creatinine ratio 209 (33-926) mg/g; 58.5% were male. Of these participants, 1883 (69.1%) were in high-risk CKD categories. Primary renal diagnosis was CKD of unknown cause in 32.3%, glomerular disease in 23.4% and diabetic kidney disease in 11.5%. Older participants and those with lower eGFR had higher systolic blood pressure and were less likely to be treated with renin-angiotensin system inhibitors (RASi) but were more likely to receive a statin. Female participants were less likely to receive a RASi or statin.

CONCLUSIONS

NURTuRE-CKD is a prospective cohort of persons who are at relatively high risk of adverse outcomes. Long-term follow-up and a large biorepository create opportunities for research to improve risk prediction and to investigate underlying mechanisms to inform new treatment development.

Efficacy and Safety of Ocedurenone: Subgroup Analysis of the BLOCK-CKD Study

BACKGROUND

Ocedurenone (KBP-5074), a nonsteroidal mineralocorticoid receptor antagonist, is documented to lower blood pressure in patients with stage 3b/4 chronic kidney disease (CKD) with uncontrolled or resistant hypertension (BLOCK-CKD study). However, the efficacy and safety of Ocedurenone in subgroups such as Hispanic patients or those with stage 4 CKD, diabetes, or very high albuminuria have not been reported.

METHODS

A total of 162 patients were enrolled in the BLOCK-CKD study. The primary endpoint of these analyses was change in systolic blood pressure (SBP) from baseline to day 84. Prespecified subgroup analysis of SBP focused on demographic (e.g., ethnicity, age) and medical (e.g., CKD stage, diabetes, albuminuria, baseline estimated glomerular filtration rate [eGFR]). The safety analysis focused on changes in serum potassium levels from baseline.

RESULTS

SBP reductions were consistent across subgroups compared with the overall study cohort. Placebo-adjusted SBP reductions were observed in Hispanic patients (-8.1 and -9.9 mm Hg for 0.25 and 0.5 mg, respectively, total n = 35) and patients with CKD stage 4 (-9.3 and -10.4 mm Hg for 0.25 and 0.5 mg, respectively, total n = 64), diabetes (-6.9 and -11.6 mm Hg for 0.25 and 0.5 mg, respectively, total n = 51), and very high albuminuria (-13.1 and -12.3 mm Hg for 0.25 and 0.5 mg, respectively, total n = 85). Changes in serum potassium were similar across all patient subgroups regardless of baseline eGFR, diabetes status, or degree of proteinuria. No cases of hyperkalemia required intervention or resulted in study discontinuation.

CONCLUSIONS

Ocedurenone consistently reduced in SBP in all patient subgroups. Moreover, while small elevations in serum potassium occurred, they were not associated with Ocedurenone or study discontinuation.

A nationwide cohort study comparing the effectiveness of diuretics and calcium channel blockers on top of renin-angiotensin system inhibitors on chronic kidney disease progression and mortality

It is unknown whether initiating diuretics on top of renin-angiotensin system inhibitors (RASi) is superior to alternative antihypertensive agents such as calcium channel blockers (CCBs) in patients with chronic kidney disease (CKD). For this purpose, we emulated a target trial in the Swedish Renal Registry 2007-2022 that included nephrologist-referred patients with moderate-advanced CKD and treated with RASi, who initiated diuretics or CCB. Using propensity score-weighted cause-specific Cox regression, we compared risks of major adverse kidney events (MAKE; composite of kidney replacement therapy [KRT], experiencing over a 40% eGFR decline from baseline, or an eGFR under 15 ml/min per 1.73m2), major cardiovascular events (MACE; composite of cardiovascular death, myocardial infarction or stroke), and all-cause mortality. We identified 5875 patients (median age 71 years, 64% men, median eGFR 26 ml/min per 1.73m2), of whom 3165 started a diuretic and 2710 a CCB. After a median follow-up of 6.3 years, 2558 MAKE, 1178 MACE and 2299 deaths occurred. Compared to CCB, diuretic use was associated with a lower risk of MAKE (weighted hazard ratio 0.87 [95% confidence interval: 0.77-0.97]), consistent across single components (KRT: 0.77 [0.66-0.88], over 40% eGFR decline: 0.80 [0.71-0.91] and eGFR under 15ml/min/1.73m2: 0.84 [0.74-0.96]). The risks of MACE (1.14 [0.96-1.36]) and all-cause mortality (1.07 [0.94-1.23]) did not differ between therapies. Results were consistent when modeling the total time drug exposure, across sub-groups and a broad range of sensitivity analyses. Thus, our observational study suggests that in patients with advanced CKD, using a diuretic rather than a CCB on top of RASi may improve kidney outcomes without compromising cardioprotection.

[REIN: a tool to support scientific research]

On the occasion of the 20th anniversary of the REIN (French Renal Epidemiology and Information Network), a summary work on the contributions of the national French ESKD register was carried out. On the issue its role in research, the following key messages were retained. The growing number of publications, dissertations, theses and teams involved shows that the REIN registry has attained its objective of being a shared research infrastructure, in the field of epidemiology as well as in public health, health economics or medical data processing. REIN is a valuable tool for the study of specific kidney diseases, particularly for epidemiological data pertaining to rare diseases that may lead to stage 5 of a chronic kidney disease. The linkage with the data from the National Healthcare Data System enables integrating and analysing the medical treatments received by patients, before the initiation of the replacement therapy and towards the end, as well as the details of the hospital stays.

Should we CLICK on chlorthalidone for treatment-resistant hypertension in chronic kidney disease?

Treatment-resistant hypertension is common among patients with advanced chronic kidney disease (CKD). In people with preserved kidney function, spironolactone is an evidence-based treatment. However, the risk for hyperkalemia limits its use in people with more advanced CKD. In the Chlorthalidone in Chronic Kidney Disease (CLICK) trial, 160 patients with stage 4 CKD and poorly controlled hypertension as confirmed by 24-hour ambulatory blood pressure (ABP) monitoring were randomly assigned to either placebo or chlorthalidone 12.5 mg daily in a 1:1 ratio stratified by prior loop diuretic use. The primary endpoint was the change in 24-hour systolic ABP from baseline to 12 weeks. The trial showed a treatment-induced reduction of 24-hour systolic ABP by 10.5 mmHg. Of the 160 patients randomized, 113 (71%) had resistant hypertension, of which 90 (80%) were on loop diuretics and the mean number of antihypertensive medications prescribed was 4.1 (standard deviation 1.1). In this subgroup of patients with treatment-resistant hypertension, the adjusted change from baseline to 12 weeks in the between-group difference in 24-hour systolic ABP was -13.9 mmHg (95% CI -19.4 to -8.4; P < .0001). Furthermore, compared with placebo, the urine albumin:creatinine ratio in the chlorthalidone group at 12 weeks was 54% lower (95% CI -65 to -40). Following randomization, hypokalemia, reversible increases in serum creatinine, hyperglycemia, dizziness, orthostatic hypotension and hyperuricemia occurred more frequently in the chlorthalidone group. Chlorthalidone has the potential to improve BP control among patients with advanced CKD and treatment-resistant hypertension. However, caution is advised when treating patients, especially when they are on loop diuretics.

Effect of finerenone on ambulatory blood pressure in chronic kidney disease in type 2 diabetes

OBJECTIVE

Finerenone is a selective nonsteroidal mineralocorticoid receptor antagonist with a short half-life. Its effects on cardiorenal outcomes were thought to be mediated primarily via nonhemodynamic pathways, but office blood pressure (BP) measurements were insufficient to fully assess hemodynamic effects. This analysis assessed the effects of finerenone on 24-h ambulatory BP in patients with chronic kidney disease and type 2 diabetes.

METHODS

ARTS-DN (NCT01874431) was a phase 2b trial that randomized 823 patients with type 2 diabetes and chronic kidney disease, with urine albumin-to-creatinine ratio ≥30 mg/g and estimated glomerular filtration rate of 30-90 ml/min per 1.73 m2 to placebo or finerenone (1.25-20 mg once daily in the morning) administered over 90 days. Ambulatory BP monitoring (ABPM) over 24 h was performed in a subset of 240 patients at screening, Day 60, and Day 90.

RESULTS

Placebo-adjusted change in 24-h ABPM systolic BP (SBP) at Day 90 was -8.3 mmHg (95% confidence interval [CI], -16.6 to 0.1) for finerenone 10 mg (n = 27), -11.2 mmHg (95% CI, -18.8 to -3.6) for finerenone 15 mg (n = 34), and -9.9 mmHg (95% CI, -17.7 to -2.0) for finerenone 20 mg (n = 31). Mean daytime and night-time SBP recordings were similarly reduced and finerenone did not increase the incidence of SBP dipping. Finerenone produced a persistent reduction in SBP over the entire 24-h interval.

CONCLUSIONS

Finerenone reduced 24-h, daytime, and night-time SBP. Despite a short half-life, changes in BP were persistent over 24 h with once-daily dosing in the morning.

Chronic kidney disease in public renal practices in Queensland, Australia, 2011-2018

AIM

To describe adults with (non-dialysis) chronic kidney disease (CKD) in nine public renal practice sites in the Australian state of Queensland.

METHODS

7,060 persons were recruited to a CKD Registry in May 2011 and until start of kidney replacement therapy (KRT), death without KRT or June 2018, for a median period of 3.4 years.

RESULTS

The cohort comprised 7,060 persons, 52% males, with a median age of 68 yr; 85% had CKD stages 3A to 5, 45.4% were diabetic, 24.6% had diabetic nephropathy, and 51.7% were obese. Younger persons mostly had glomerulonephritis or genetic renal disease, while older persons mostly had diabetic nephropathy, renovascular disease and multiple diagnoses. Proportions of specific renal diagnoses varied >2-fold across sites. Over the first year, eGFR fell in 24% but was stable or improved in 76%. Over follow up, 10% started KRT, at a median age of 62 yr, most with CKD stages 4 and 5 at consent, while 18.8% died without KRT, at a median age of 80 yr. Indigenous people were younger at consent and more often had diabetes and diabetic kidney disease and had higher incidence rates of KRT.

CONCLUSION

The spectrum of characteristics in CKD patients in renal practices is much broader than represented by the minority who ultimately start KRT. Variation in CKD by causes, age, site and Indigenous status, the prevalence of obesity, relative stability of kidney function in many persons over the short term, and differences between those who KRT and die without KRT are all important to explore.

Sirt6 deficiency contributes to mitochondrial fission and oxidative damage in podocytes via ROCK1-Drp1 signalling pathway

OBJECTIVES

Increasing evidence suggests that mitochondrial dysfunction is the key driver of angiotensin II (Ang II)-induced kidney injury. This study was designed to investigate whether Sirtuin 6 (Sirt6) could affect Ang II-induced mitochondrial damage and the potential mechanisms.

MATERIALS AND METHODS

Podocyte-specific Sirt6 knockout mice were infused with Ang II and cultured podocytes were stimulated with Ang II to evaluate the effects of Sirt6 on mitochondrial structure and function in podocytes. Immunofluorescence staining was used to detect protein expression and mitochondrial morphology in vitro. Electron microscopy was used to assess mitochondrial morphology in mice. Western blotting was used to quantify protein expression.

RESULTS

Mitochondrial fission and decreased Sirt6 expression were observed in podocytes from Ang II-infused mice. In Sirt6-deficient mice, Ang II infusion induced increased apoptosis and mitochondrial fragmentation in podocytes than that in Ang II-infused wild-type mice. In cultured human podocytes, Sirt6 knockdown exacerbated Ang II-induced mitochondrial fission, whereas Sirt6 overexpression ameliorated the Ang II-induced changes in the balance between mitochondrial fusion and fission. Functional studies revealed that Sirt6 deficiency exacerbated mitochondrial fission by promoting dynamin-related protein 1 (Drp1) phosphorylation. Furthermore, Sirt6 mediated Drp1 phosphorylation by promoting Rho-associated coiled coil-containing protein kinase 1 (ROCK1) expression.

CONCLUSION

Our study has identified Sirt6 as a vital factor that protects against Ang II-induced mitochondrial fission and apoptosis in podocytes via the ROCK1-Drp1 signalling pathway.

Management of hypertension in advanced kidney disease

PURPOSE OF REVIEW

The aim of this study was to present recent developments in pharmacotherapy of hypertension in patients with advanced chronic kidney disease (CKD).

RECENT FINDINGS

In the AMBER trial, compared with placebo, the potassium-binder patiromer mitigated the risk of hyperkalaemia and enabled more patients with uncontrolled resistant hypertension and stage 3b/4 CKD to tolerate and continue spironolactone treatment; add-on therapy with spironolactone provoked a clinically meaningful reduction of 11-12 mmHg in unattended automated office SBP over 12 weeks of follow-up. In the BLOCK-CKD trial, the investigational nonsteroidal mineralocorticoid-receptor-antagonist (MRA) KBP-5074 lowered office SBP by 7-10 mmHg relative to placebo at 84 days with a minimal risk of hyperkalaemia in patients with advanced CKD and uncontrolled hypertension. The CLICK trial showed that the thiazide-like diuretic chlorthalidone provoked a placebo-subtracted reduction of 10.5 mmHg in 24-h ambulatory SBP at 12 weeks in patients with stage 4 CKD and poorly controlled hypertension.

SUMMARY

Enablement of more persistent spironolactone use with newer potassium-binding agents, the clinical development of novel nonsteroidal MRAs with a more favourable benefit-risk profile and the recently proven blood pressure lowering action of chlorthalidone are three therapeutic opportunities for more effective management of hypertension in high-risk patients with advanced CKD.

New wrinkles in hypertension management 2022

PURPOSE OF REVIEW

High blood pressure (BP) is the world's leading risk factor for cardiovascular disease (CVD) and death. This review highlights findings during the past 18 months that apply to the management of high BP in adults in the context of the 2017 American College of Cardiology/American Heart Association (AHA) BP guideline.

RECENT FINDINGS

A comprehensive meta-analysis of clinical trials that employed a novel statistical method identified a substantially linear relationship between dietary sodium intake and BP, strongly supporting the AHA daily dietary sodium intake recommendation of less than 1500 mg/day but suggesting that any reduction in sodium intake is likely to be beneficial. Among adults with hypertension, use of a salt substitute (containing reduced sodium and enhanced potassium) led to striking reductions in CVD outcomes. Young adults with stage 1 hypertension and a low 10-year atherosclerotic CVD risk score should be started on a 6-month course of vigorous lifestyle modification; if their BP treatment goal is not achieved, a first-line antihypertensive agent should be added to the lifestyle modification intervention. In patients with stage 4 renal disease, the thiazide-like diuretic chlorthalidone (as add-on therapy) lowered BP markedly compared with placebo. Nonsteroidal mineralocorticoid receptor antagonists (MRAs) represent a new class of MRA that has been shown to lower BP and provide significant CVD protection. In Chinese adults aged 60-80 years at baseline, intensive BP control with a SBP target of 110-129 compared with 130-149 mmHg reduced CVD events with minimal side effects.

SUMMARY

Recent findings have advanced our knowledge of hypertension management, clarifying, amplifying and supporting the 2017 ACC/AHA BP guideline recommendations.

Cardiovascular Implications of the 2021 KDIGO Blood Pressure Guideline for Adults With Chronic Kidney Disease

BACKGROUND

The 2021 Kidney Disease: Improving Global Outcomes (KDIGO) guideline recommends a systolic blood pressure (BP) target of <120 mm Hg for nondialysis chronic kidney disease (CKD).

OBJECTIVES

We sought to examine the potential implications of the 2021 KDIGO BP target, compared with the 2012 KDIGO and 2017 American College of Cardiology (ACC)/American Heart Association (AHA) BP targets, as related to cardiovascular disease (CVD) outcomes.

METHODS

From the cross-sectional Korea National Health and Nutrition Examination Survey (KNHANES) and longitudinal National Health Insurance Service (NHIS) data, adults with nondialysis CKD were identified and categorized into 4 groups based on concordance/discordance between guidelines: 1) above both targets; 2) above 2021 KDIGO only; 3) above 2012 KDIGO or 2017 ACC/AHA only; and 4) controlled within both targets. We determined the nationally representative proportion and CVD risk of each group.

RESULTS

In KNHANES (n = 1,939), 50.2% had BP above both 2021 and 2012 KDIGO targets, 15.9% above the 2021 KDIGO target only, 3.5% above the 2012 KDIGO target only, and 30.4% controlled within both targets. In NHIS (n = 412,167; median follow-up: 10.0 years), multivariable-adjusted HRs for CVD events were 1.52 (95% CI: 1.47-1.58) among participants with BP above both targets, 1.28 (95% CI: 1.24-1.32) among those with BP above 2021 KDIGO only, and 1.07 (95% CI: 0.61-1.89) among those with BP above 2012 KDIGO only, compared to those with BP controlled within both targets. Results were similar for comparison between 2021 KDIGO and 2017 ACC/AHA BP targets.

CONCLUSIONS

New candidates for BP-lowering treatment per the 2021 KDIGO guideline account for a substantial proportion of the total CKD population and bear significantly high CVD risk.

The Indian Chronic Kidney Disease (ICKD) study: baseline characteristics

Background

Chronic kidney disease (CKD) is an important cause of morbidity and mortality worldwide. There is a lack of information on epidemiology and progression of CKD in low–middle income countries. The Indian Chronic Kidney Disease (ICKD) study aims to identify factors that associate with CKD progression, and development of kidney failure and cardiovascular disease (CVD) in Indian patients with CKD.

Methods

ICKD study is prospective, multicentric cohort study enrolling patients with estimated glomerular filtration rate (eGFR) 15–60 mL/min/1.73 m², or >60 mL/min/1.73 m² with proteinuria. Clinical details and biological samples are collected at annual visits. We analysed the baseline characteristics including socio-demographic details, risk factors, disease characteristics and laboratory measurements. In addition, we compared characteristics between urban and rural participants.

Results

A total of 4056 patients have been enrolled up to 31 March 2020. The mean ± SD age was 50.3 ± 11.8 years, 67.2% were males, two-thirds of patients lived in rural areas and the median eGFR was 40 mL/min/1.73 m². About 87% were hypertensive, 37% had diabetes, 22% had CVD, 6.7% had past history of acute kidney injury and 23% reported prior use of alternative drugs. Diabetic kidney disease, chronic interstitial nephritis (CIN) and CKD-cause unknown (CKDu) were the leading causes. Rural participants had more occupational exposure and tobacco use but lower educational status and income. CIN and unknown categories were leading causes in rural participants.

Conclusions

The ICKD study is the only large cohort study of patients with mild-to-moderate CKD in a lower middle income country. Baseline characteristics of study population reveal differences as compared with other cohorts from high-income countries.

Chlorthalidone for Hypertension in Advanced Chronic Kidney Disease

BACKGROUND

Little evidence has been available to support the use of thiazide diuretics to treat hypertension in patients with advanced chronic kidney disease.

METHODS

We randomly assigned patients with stage 4 chronic kidney disease and poorly controlled hypertension, as confirmed by 24-hour ambulatory blood-pressure monitoring, in a 1:1 ratio to receive chlorthalidone at an initial dose of 12.5 mg per day, with increases every 4 weeks if needed to a maximum dose of 50 mg per day, or placebo; randomization was stratified according to previous use of loop diuretics. The primary outcome was the change in 24-hour ambulatory systolic blood pressure from baseline to 12 weeks. Secondary outcomes were the change from baseline to 12 weeks in the urinary albumin-to-creatinine ratio, N-terminal pro-B-type natriuretic peptide level, plasma renin and aldosterone levels, and total body volume. Safety was also assessed.

RESULTS

A total of 160 patients underwent randomization, of whom 121 (76%) had diabetes mellitus and 96 (60%) were receiving loop diuretics. At baseline, the mean (±SD) estimated glomerular filtration rate was 23.2±4.2 ml per minute per 1.73 m2 of body-surface area and the mean number of antihypertensive medications prescribed was 3.4±1.4. At randomization, the mean 24-hour ambulatory systolic blood pressure was 142.6±8.1 mm Hg in the chlorthalidone group and 140.1±8.1 mm Hg in the placebo group and the mean 24-hour ambulatory diastolic blood pressure was 74.6±10.1 mm Hg and 72.8±9.3 mm Hg, respectively. The adjusted change in 24-hour systolic blood pressure from baseline to 12 weeks was -11.0 mm Hg (95% confidence interval [CI], -13.9 to -8.1) in the chlorthalidone group and -0.5 mm Hg (95% CI, -3.5 to 2.5) in the placebo group. The between-group difference was -10.5 mm Hg (95% CI, -14.6 to -6.4) (P<0.001). The percent change in the urinary albumin-to-creatinine ratio from baseline to 12 weeks was lower in the chlorthalidone group than in the placebo group by 50 percentage points (95% CI, 37 to 60). Hypokalemia, reversible increases in serum creatinine level, hyperglycemia, dizziness, and hyperuricemia occurred more frequently in the chlorthalidone group than in the placebo group.

CONCLUSIONS

Among patients with advanced chronic kidney disease and poorly controlled hypertension, chlorthalidone therapy improved blood-pressure control at 12 weeks as compared with placebo. (Funded by the National Heart, Lung, and Blood Institute and the Indiana Institute of Medical Research; CLICK ClinicalTrials.gov number, NCT02841280.).

Persistent Resistant Hypertension Has Worse Renal Outcomes in Chronic Kidney Disease than that Resolved in Two Years: Results from the KNOW-CKD Study

Apparent treatment-resistant hypertension (ATRH) is closely related to chronic kidney disease (CKD); however, the long-term outcomes and the effects of improvement in ATRH in patients with CKD are not well understood. We evaluated the relationship between the persistence of ATRH and the progression of CKD. This cohort study enrolled 1921 patients with CKD. ATRH was defined as blood pressure above 140/90 mmHg and intake of three different types of antihypertensive agents, including diuretics, or intake of four or more different types of antihypertensive agents, regardless of blood pressure. We defined ATRH subgroups according to the ATRH status at the index year and two years later. The prevalence of ATRH at baseline was 14.0%. The presence of ATRH at both time points was an independent risk factor for end-point renal outcome (HR, 1.41; 95% CI, 1.04–1.92; p = 0.027). On the other hand, the presence of ATRH at any one of the time points was not statistically significant. In conclusion, persistent ATRH is more important for the prognosis of renal disease than the initial ATRH status. Continuous follow-up and appropriate treatment are important to improve the renal outcomes.

Association of Blood Pressure with Cardiovascular Outcome and Mortality: Results from the KNOW-CKD Study

BACKGROUND

Optimal BP control is a major therapeutic strategy to reduce adverse cardiovascular events and mortality in patients with CKD. We studied the association of BP with adverse cardiovascular outcome and all-cause death in patients with CKD.

METHODS

Among 2,238 participants from the KoreaN cohort study for Outcome in patients With CKD, 2,226 patients with baseline BP measurements were enrolled. Main predictor was SBP categorized by 5 levels: <110, 110-119, 120-129, 130-139, and ≥140 mmHg. Primary endpoint was a composite outcome of all-cause death or incident cardiovascular events. We primarily used marginal structural models using averaged and the most recent time-updated SBPs.

RESULTS

During a median follow-up of 10233.79 person-years (median 4.60 years), the primary composite outcome occurred in 240 (10.8%) participants, with a corresponding incidence rate of 23.5 (95% CI, 20.7-26.6) per 1,000 patient-years. Marginal structural models with averaged SBP showed a U-shaped relationship with the primary outcome. Compared to time-updated SBP of 110-119 mmHg, hazard ratios (95% CI) for <110, 120-129, 130-139, and ≥140 mmHg were 2.47 (1.48-4.11), 1.29 (0.80-2.08), 2.15 (1.26-3.69), and 2.19 (1.19-4.01), respectively. Marginal structural models with the most recent SBP also showed similar findings.

CONCLUSIONS

In Korean patients with CKD, there was a U-shaped association of SBP with the risk of adverse clinical outcome. Our findings highlight the importance of BP control and suggest a potential hazard of SBP <110 mmHg.

Prescription Practices in Patients With Mild to Moderate CKD in India

INTRODUCTION

Patients with chronic kidney disease (CKD) require multiple medications. There is no information on prescription patterns or the use of evidence-based therapies for management of CKD from low-middle-income countries. Using baseline data from the Indian CKD (ICKD) cohort, we describe the drug prescription practices in patients with mild to moderate CKD.

METHODS

The ICKD study is a prospective, observational cohort study of mild to moderate kidney disease across 11 centers in India. We analyzed all the prescriptions captured at enrollment in the ICKD study. Drugs were categorized into 11 different groups. We provide descriptive data on prescription details and evaluate the appropriateness of medication use.

RESULTS

Complete prescription data were available in 3966 out of 4056 (97.8%) subjects enrolled in the ICKD database. Most patients had stage 3 CKD, 24.9% had diabetic kidney disease, 87% had hypertension, and 25.5% had moderate to severe proteinuria. Renin-angiotensin-aldosterone system blockers were prescribed in less than half (47.9%) and in 58.8% of patients with proteinuric CKD. Metformin was prescribed in 25.7% of diabetic subjects with CKD. Only 40.4% of patients were taking statins; 31.1% and 2.8% subjects with anemia were receiving iron and erythropoiesis-stimulating agents, respectively.

CONCLUSION

This study highlights the missed opportunities for improving outcomes through appropriate prescriptions of drugs in patients with CKD. There is need for dissemination of evidence-based guidelines and institution of sustainable implementation practices for improving the overall health of patients with CKD.

Polypharmacy and the Progression of Chronic Kidney Disease: Korean Cohort Study for Outcome in Patients with Chronic Kidney Disease

INTRODUCTION

The renal hazard of polypharmacy has never been evaluated in predialysis chronic kidney disease (CKD) patients.

OBJECTIVE

We aimed to analyze the renal hazard of polypharmacy in predialysis CKD patients with stage 1-5.

METHOD

The data of 2,238 patients from a large-scale multicenter prospective Korean study (2011-2016), excluding 325 patients with various missing data, were reviewed. Polypharmacy was defined as taking 6 or more medications at the time of enrollment; renal events were defined as a ≥50% decrease in kidney function from baseline values, doubling of the serum creatinine levels, or initiation of renal replacement treatment. Hazard ratio (HR) and 95% confidence interval (CI) were calculated using Cox proportional-hazard regression analysis.

RESULTS

Of the 1,913 patients, the mean estimated glomerular filtration rate was 53.6 mL/min/1.73 m2. The mean medication count was 4.1, and the prevalence of polypharmacy was 27.1%. During the average period of 3.6 years, 520 patients developed renal events (27.2%). Although increased medication counts were associated with increased renal hazard with HR (95% CI) of 1.056 (1.007-1.107, p = 0.025), even after adjusting for various confounders, adding comorbidity score and kidney function nullified the statistical significance. In mediation analysis, 55.6% (p = 0.016) of renal hazard in increased medication counts was mediated by the kidney function, and there was no direct effect of medication counts on renal event development. In subgroup analysis, the renal hazard of the medication counts was evident only in stage 1-3 of CKD patients (p for interaction = 0.014).

CONCLUSIONS

We cannot identify the direct renal hazard of multiple medications, and most of the potential renal hazard was derived from intimate relationship with disease burden and kidney function.

International Society of Nephrology Global Kidney Health Atlas: structures, organization, and services for the management of kidney failure in Western Europe

Populations in the high-income countries of Western Europe are aging due to increased life expectancy. As the prevalence of diabetes and obesity has increased, so has the burden of kidney failure. To determine the global capacity for kidney replacement therapy and conservative kidney management, the International Society of Nephrology conducted multinational, cross-sectional surveys and published the findings in the International Society of Nephrology Global Kidney Health Atlas. In the second iteration of the International Society of Nephrology Global Kidney Health Atlas, we aimed to describe the availability, accessibility, quality, and affordability of kidney failure care in Western Europe. Among the 29 countries in Western Europe, 21 (72.4%) responded, representing 99% of the region's population. The burden of kidney failure prevalence varied widely, ranging from 760 per million population (pmp) in Iceland to 1612 pmp in Portugal. Coverage of kidney replacement therapy from public funding was nearly universal, with the exceptions of Germany and Liechtenstein where part of the costs was covered by mandatory insurance. Fourteen (67%) of 21 countries charged no fees at the point of care delivery, but in 5 countries (24%), patients do pay some out-of-pocket costs. Long-term dialysis services (both hemodialysis and peritoneal dialysis) were available in all countries in the region, and kidney transplantation services were available in 19 (90%) countries. The incidence of kidney transplantation varied widely between countries from 12 pmp in Luxembourg to 70.45 pmp in Spain. Conservative kidney care was available in 18 (90%) of 21 countries. The median number of nephrologists was 22.9 pmp (range: 9.47-55.75 pmp). These data highlight the uniform capacity of Western Europe to provide kidney failure care, but also the scope for improvement in disease prevention and management, as exemplified by the variability in disease burden and transplantation rates.

Methods and rationale of the DISCOVER CKD global observational study

Background

Real-world data for patients with chronic kidney disease (CKD), specifically pertaining to clinical management, metabolic control, treatment patterns, quality of life (QoL) and dietary patterns, are limited. Understanding these gaps using real-world, routine care data will improve our understanding of the challenges and consequences faced by patients with CKD, and will facilitate the long-term goal of improving their management and prognosis.

Methods

DISCOVER CKD follows an enriched hybrid study design, with both retrospective and prospective patient cohorts, integrating primary and secondary data from patients with CKD from China, Italy, Japan, Sweden, the UK and the USA. Data will be prospectively captured over a 3-year period from >1000 patients with CKD who will be followed up for at least 1 year via electronic case report form entry during routine clinical visits and also via a mobile/tablet-based application, enabling the capture of patient-reported outcomes (PROs). In-depth interviews will be conducted in a subset of ∼100 patients. Separately, secondary data will be retrospectively captured from >2 000 000 patients with CKD, extracted from existing datasets and registries.

Results

The DISCOVER CKD program captures and will report on patient demographics, biomarker and laboratory measurements, medical histories, clinical outcomes, healthcare resource utilization, medications, dietary patterns, physical activity and PROs (including QoL and qualitative interviews).

Conclusions

The DISCOVER CKD program will provide contemporary real-world insight to inform clinical practice and improve our understanding of the epidemiology and clinical and economic burden of CKD, as well as determinants of clinical outcomes and PROs from a range of geographical regions in a real-world CKD setting.

The Global Kidney Health Atlas: Burden and Opportunities to Improve Kidney Health Worldwide

CKD is a growing public health problem. The Global Kidney Health Atlas (GKHA) is an important initiative of the International Society of Nephrology. The GKHA aims to improve the understanding of inter- and intranational variability across the globe, focusing on capacity for kidney care delivery. The GKHA survey was launched in 2017 and then again in 2019, using the same core data, supplemented by information about dialysis access and conservative care. Based on a WHO framework of the 6 building blocks essential for health care, the GKHA assesses capacity in 6 domains: information systems, services delivery, workforce, financing, access to essential medicines, and leadership/governance. In addition, the GKHA assesses the capacity for research in all regions of the world, across all domains (basic, translational, clinical, and health system research). The results of the GKHA have informed policy and been used to enhance advocacy strategies in different regions. In addition, through documentation of the disparities within and between countries and regions, initiatives have been launched to foster change. Since the first survey, there has been an increase in the number of countries which have registries to document the burden of CKD or dialysis. For many, information about the burden of disease is the first step toward addressing care delivery issues, including prevention, delay of progression, and access to services. Worldwide collaboration in the documentation of kidney health and disease is an important step toward the goal of ensuring equitable access to kidney health worldwide.

Systolic blood pressure and chronic kidney disease progression in patients with primary glomerular disease

INTRODUCTION

Many current guidelines on optimal target blood pressure (BP) for chronic kidney disease (CKD) patients are largely based on studies in diabetic and hypertensive patients. However, there have been few studies in patients with glomerular diseases.

METHODS

We retrospectively studied the longitudinal association between BP and CKD progression in 1,066 biopsy-proven patients diagnosed with primary glomerular diseases, including IgA nephropathy, membranous nephropathy (MN), and focal segmental glomerulosclerosis (FSGS), between 2005 and 2017. The main predictor was time-updated systolic blood pressure (SBP) at every clinic visit. The primary outcome was a composite one including ≥ 50% decrease in estimated glomerular filtration rate (eGFR) from the baseline, and end-stage kidney disease (ESKD).

RESULTS

During 5009 person-years of follow-up, the primary outcome occurred in 157 (14.7%) patients. In time-varying Cox model, the adjusted hazard ratios (HRs) (95% confidence interval (CI)) for the primary outcome were 1.48 (0.96-2.29), 2.07 (1.22-3.52), and 2.53 (1.13-5.65) for SBP of 120-129, 130-139, and ≥ 140 mmHg, respectively, compared with SBP < 120 mmHg. This association was particularly evident in patients with elevated proteinuria. However, there was no association between baseline SBP and adverse kidney outcomes. Finally, prediction models failed to show the improvement of predictive performance of SBP compared with that of remission status. Moreover, patients with remission and less controlled SBP had better kidney outcomes than those with non-remission and well-controlled SBP.

CONCLUSION

Among patients with glomerular disease, higher time-updated SBP was significantly associated with higher risk of CKD progression. However, the clinical significance of blood pressure was less powerful than remission status.

Trajectory of extracellular fluid volume over time and subsequent risks of end-stage kidney disease and mortality in chronic kidney disease: a prospective cohort study

BACKGROUND

Extracellular fluid volume (ECF) is independently associated with chronic kidney disease (CKD) progression and mortality in patients with CKD, but the prognostic value of the trajectory of ECF over time beyond that of baseline value is unknown.

OBJECTIVES

To characterize ECF trajectory and evaluate its association with the risks of end-stage kidney disease (ESKD) and mortality.

METHODS

From the prospective tricentric NephroTest cohort, we included 1588 patients with baseline measured glomerular filtration rate (mGFR) ≥15 mL min^-1 /1.73 m² and ECF measurement. ECF and GFR were measured repeatedly using the distribution volume and clearance of ⁵¹ Cr-EDTA, respectively. ESKD and mortality were traced through record linkage with the national registries. Adjusted shared random-effect joint models were used to analyse the association between the trajectory of ECF over time and the two competing outcomes.

RESULTS

Patients were mean age 58.7 years, 66.7% men, mean mGFR of 43.6 ± 18.6 mL min^-1 /1.73 m² and mean ECF of 16.1 ± 3.6 L. Over a median follow-up of 5.3 [IQR: 3.0;7.4] years, ECF increased by 136 [95%CI 106;167] mL per year on average, whilst diuretic prescription and 24-hour urinary sodium excretion remained stable. ESKD occurred in 324 (20.4%) patients, and 185 (11.6%) patients died before ESKD. A higher current value of ECF was associated with increased hazards of ESKD (adjusted hazard ratio [aHR]: 1.12 [95%CI 1.06;1.18]; P < 0.001 per 1 L increase in ECF), and death before ESKD (aHR: 1.10 [95%CI 1.04;1.17]; P = 0.002).

CONCLUSIONS

The current value of ECF was associated with the risks of ESKD and mortality, independent of multiple potential confounders, including kidney function decline. This highlights the need for a close monitoring and adjustment of treatment to avoid fluid overload in CKD patients.

Cardiovascular disease history and β-blocker prescription patterns among Japanese and American patients with CKD: a cross-sectional study of the CRIC and CKD-JAC studies

Cardiovascular disease (CVD) is a major complication in individuals with chronic kidney disease (CKD). In Japan, the incidence of CVD among persons with CKD is lower than that in the United States. Although various classes of antihypertensive agents are prescribed to prevent CVD, the proportion varies between the United States and Japan. Until now, few studies have compared clinical practices and CVD prevalence among patients with CKD in the United States vs. Japan. In this study, we performed a cross-sectional comparison of the prevalence of CVD and the prescription of β-blockers at study entry to the Chronic Kidney Disease Japan Cohort (CKD-JAC) Study and the Chronic Renal Insufficiency Cohort (CRIC) Study. The mean patient age was 58.2 and 60.3 years, the mean estimated glomerular filtration rate (eGFR) was 42.8 and 28.9 (mL/min/1.73 m²), and the median urinary albumin:creatinine ratio was 51.9 and 485.9 (mg/g) among 3939 participants in the CRIC Study and 2966 participants in the CKD-JAC Study, respectively. The prevalence of any CVD according to a self-report (CRIC Study) was 33%, while that according to a medical chart review (CKD-JAC Study) was 24%. These findings were consistent across eGFR levels. Prescriptions for β-blockers differed between the CRIC and CKD-JAC Studies (49% and 20%, respectively). The odds ratios for the association of any history of CVD and β-blocker prescription were 3.0 [2.6-3.5] in the CRIC Study and 2.0 [1.6-2.5] in the CKD-JAC Study (P < 0.001 for the interaction). In conclusion, the prevalence of CVD and treatment with β-blockers were higher in the CRIC Study across eGFR levels.

Patiromer and Spironolactone in Resistant Hypertension and Advanced CKD: Analysis of the Randomized AMBER Trial

Background

Mineralocorticoid receptor antagonists reduce mortality in patients with heart failure with reduced ejection fraction and have become a standard of care in those with resistant hypertension (rHTN). Yet, their use is limited among patients with CKD, primarily due to hyperkalemia.

Methods

AMBER was a multicenter, randomized, double-blind, placebo-controlled, parallel-group study that reported that the use of the potassium-binding drug patiromer allowed a more persistent use of spironolactone in patients with CKD and rHTN. In this report, we compare the safety and efficacy of patiromer in advanced CKD as a prespecified analysis.

Results

Of the 295 patients randomized, 66 fell into the eGFR 25 to <30 subgroup. In this subgroup, persistent use of spironolactone was seen in 19 of 34 (56%) in the placebo group and 27 of 32 (84%) in the patiromer group (absolute difference 29%; P<0.02). In the eGFR 30-45 subgroup, persistent use of spironolactone was seen in 79 of 114 (69%) in the placebo group and 99 of 115 (86%) in the patiromer group (absolute difference 17%; P=0.003). There was no significant interaction between eGFR subgroups (P=0.46). Systolic BP reduction with spironolactone in the eGFR 25 to <30 subgroup was 6-7 mm Hg; in the eGFR 30-45 subgroup, it was 12-13 mm Hg. There was no significant interaction between eGFR subgroups on BP reduction (P=0.79). Similar proportions of patients reported adverse events (59% in the eGFR 25 to <30 subgroup; 53% in the eGFR 30-45 subgroup).

Conclusions

Patiromer facilitates the use of spironolactone among patients with rHTN, and its efficacy and safety are comparable in those with eGFR 25 to <30 and 30-45 ml/min per 1.73 m².

Clinical Trial registry name and registration number

Clinicaltrials.gov, NCT03071263.

Incidence of cardiovascular events and mortality in Korean patients with chronic kidney disease

Few studies have investigated the incidence of cardiovascular disease (CVD) in the Asian chronic kidney disease (CKD) population. This study assessed the incidence of CVD, death, and a composite outcome of CVD and death in a prospective Korean predialysis CKD cohort. From a total of 2179 patients, incidence rates were analyzed, and competing risk analyses were conducted according to CKD stage. Additionally, incidence was compared to the general population. During a median 4.1 years of follow-up, the incidence of CVD, all-cause death, and the composite outcome was 17.2, 9.6, and 24.5 per 1000 person-years, respectively. These values were higher in diabetic vs. non-diabetic subjects (P < 0.001). For all outcomes, incidence rates increased with increasing CKD stage (CVD, P = 0.001; death, P < 0.001; and composite, P < 0.001). Additionally, CKD stage G4 [hazard ratio (HR) 2.8, P = 0.008] and G5 (HR 5.0, P < 0.001) were significant risk factors for the composite outcome compared to stage G1 after adjustment. Compared to the general population, the total cohort population (stages G1-G5) showed significantly higher risk of CVD (HR 2.4, P < 0.001) and the composite outcome (HR 1.7, P < 0.001). The results clearly demonstrate that CKD is a risk factor for CVD in an Asian population.

Adherence to the Kidney Disease: Improving Global Outcomes CKD Guideline in Nephrology Practice Across Countries

Introduction

The uptake of the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 chronic kidney disease (CKD) Guideline is not fully described in real-world nephrology practice across the world.

Methods

We used baseline data from the CKD Outcomes and Practice Patterns Study (2013-2017), a 4-country cohort of patients with estimated glomerular filtration rate <60 ml/min per 1.73 m² recruited from national samples of nephrology clinics, to describe adherence to measures for monitoring and delaying CKD progression. Data were collected as in clinical practice, except laboratory measures per protocol in France.

Results

The mean age ranged from 65 years in Brazil to 72 years in Germany. Albuminuria (mostly proteinuria) was measured routinely in 36% to 43% of patients in Brazil, Germany, and the United States. Blood pressure control (≤140/90 mm Hg) ranged from 49% in France to 76% in Brazil; <40% of patients had blood pressure ≤130/80 mm Hg everywhere but Brazil (52%). More than 40% of nephrologists in Brazil reported a systolic blood pressure target ≤130 mm Hg for nondiabetic patients without proteinuria, but only 19% to 24% elsewhere. Prescription of renin-angiotensin aldosterone system inhibitors ranged from 52% in the United States to 81% in Germany. Dietary advice was more frequent for salt than protein intake; dietitian visits were uncommon. In nondiabetic patients, achievement of all 3 targets including blood pressure ≤130/80 mm Hg, renin-angiotensin aldosterone system inhibition, and dietary advice, ranged from 10% in the United States to 32% in Brazil; in treated diabetic patients, this ranged from 6% to 11% after including hemoglobin A1c target.

Conclusion

Adherence to recommendations to slow CKD progression is low in typical practice settings, and substantial variation among countries for some indicates opportunities for improvement.

Pharmacoepidemiology for nephrologists (part 1): concept, applications and considerations for study design

Randomized controlled trials on drug safety and effectiveness are the foundation of medical evidence, but they may have limited generalizability and be unpowered to detect rare and long-term kidney outcomes. Observational studies in routine care data can complement and expand trial evidence on the use, safety and effectiveness of medications and aid with clinical decisions in areas where evidence is lacking. Access to routinely collected large healthcare data has resulted in the proliferation of studies addressing the effect of medications in patients with kidney diseases and this review provides an introduction to the science of pharmacoepidemiology to critically appraise them. In this first review we discuss the concept and applications of pharmacoepidemiology, describing methods for drug-utilization research and discussing the strengths and caveats of the most commonly used study designs to evaluate comparative drug safety and effectiveness.

Worldwide Disparity in the Relation Between CKD Prevalence and Kidney Failure Risk

Introduction

The incidence of kidney replacement therapy (KRT) for kidney failure varies internationally much more than chronic kidney disease (CKD) prevalence. This ecologic study investigated the relation of CKD prevalence to KRT and mortality risks by world region.

Methods

We used data from Global Burden of Disease and KRT registries worldwide with linear models to estimate the percentages of variance in KRT incidence and all-cause mortality explained by age-adjusted prevalence of CKD stages 3 to 5, overall and by gender, in 61 countries classified in 3 regions: high income (n = 28), Eastern and Central Europe (n = 15), and other (n = 18).

Results

The incidence of KRT ranged from 89 to 378 per million population in high-income regions, 32 to 222 per million population in Central and Eastern Europe, and 22 to 493 per million population in the other region; age-adjusted CKD prevalence ranged from 5.5% to 10.4%, 7.6% to 13.7%, and 7.4% to 13.1%, respectively. The relation between these indicators was positive in high-income countries, negative in Central and Eastern Europe, and null in the other region. Age-adjusted CKD prevalence explained 40% of the variance in KRT incidence (P < 0.001) in high-income countries. The explained variance of age-adjusted mortality was close to 0 in high-income countries and positive at 19% (P = 0.10) in Central and Eastern Europe and at 11% (P = 0.17) in the other region. Results were consistent by gender.

Conclusion

This study raises awareness on the significant part of the gaps in KRT incidence across countries not explained by the number of individuals with CKD, even in high-income countries where access to KRT is not limited.

Resistant Hypertension in Chronic Kidney Disease (CKD): Prevalence, Treatment Particularities, and Research Agenda

PURPOSE OF REVIEW

To explore the prevalence, treatment particularities, and research agenda in the management of resistant hypertension among patients with chronic kidney disease (CKD).

RECENT FINDINGS

The prevalence of resistant hypertension is reported to be 2-3 times higher in patients with CKD than in the general hypertensive population. Based in part on the results of the PATHWAY-2 trial showing add-on spironolactone to be superior to placebo or active treatment with an α- or β-blocker in reducing BP, international guidelines recommend the use of spironolactone as fourth-line agent in pharmacotherapy of resistant hypertension. Despite the several-fold higher burden of resistant hypertension among patients with stage 3b-4 CKD, the use of spironolactone in this population has been restricted, mainly due to the risk of hyperkalemia. The recently reported AMBER trial showed that among patients with uncontrolled resistant hypertension and an estimated glomerular filtration rate of 25-45 ml/min/1.73m², the newer potassium-binder patiromer prevented the development of hyperkalemia and increased the proportion of participants who remained on add-on spironolactone over 12 weeks of follow-up. Administration of spironolactone was associated with a clinically meaningful reduction of 11-12 mmHg in unattended automated office systolic blood pressure (BP) over the course of the AMBER trial. Newer potassium-binding therapies overcome the barrier of hyperkalemia and facilitate the persistent use of spironolactone, which is an effective add-on therapy to control BP in patients with resistant hypertension and advanced CKD. Future trials are now warranted to explore whether this strategy confers benefits on "hard" clinical outcomes in this high-risk population.