Effect of Intensive Blood Pressure Lowering on Kidney Tubule Injury: Findings From the ACCORD Trial Study Participants

Representation of Real-World Adults With Chronic Kidney Disease in Clinical Trials Supporting Blood Pressure Treatment Targets

BACKGROUND

Little is known about how well trial participants with chronic kidney disease (CKD) represent real-world adults with CKD. We assessed the population representativeness of clinical trials supporting the 2021 Kidney Disease: Improving Global Outcomes blood pressure (BP) guidelines in real-world adults with CKD.

METHODS AND RESULTS

Using a cross-sectional analysis, we identified patients with CKD who met the guideline definition of hypertension based on use of antihypertensive medications or sustained systolic BP ≥120 mm Hg in 2019 in the Veterans Affairs and Kaiser Permanente of Southern California. We applied the eligibility criteria from 3 BP target trials, SPRINT (Systolic Pressure Intervention Trial), ACCORD (Action to Control Cardiovascular Risk in Diabetes), and AASK (African American Study of Kidney Disease), to estimate the proportion of adults with a systolic BP above the guideline-recommended target and the proportion who met eligibility criteria for ≥1 trial. We identified 503 480 adults in the Veterans Affairs and 73 412 adults in Kaiser Permanente of Southern California with CKD and hypertension in 2019. We estimated 79.7% in the Veterans Affairs and 87.3% in the Kaiser Permanente of Southern California populations had a systolic BP ≥120 mm Hg; only 23.8% [23.7%-24.0%] in the Veterans Affairs and 20.8% [20.5%-21.1%] in Kaiser Permanente of Southern California were trial-eligible. Among trial-ineligible patients, >50% met >1 exclusion criteria.

CONCLUSIONS

Major BP target trials were representative of fewer than 1 in 4 real-world adults with CKD and hypertension. A large proportion of adults who are at risk for cardiovascular morbidity from hypertension and susceptible to adverse treatment effects lack relevant treatment information.

YKL-40 (chitinase-3-like protein 1) serum levels are associated with abdominal aortic calcification in hemodialysis patients

BACKGROUND

Vascular calcification (VC) is highly prevalent and predicts cardiovascular mortality in dialysis patients. The mechanisms are still unclear. Inflammation is a well-known inducer of VC. YKL-40 has been suggested as a novel biomarker of inflammation and has been demonstrated to be associated with cardiovascular mortality in hemodialysis patients. This study aims to evaluate the relationship between serum YKL-40 and VC in hemodialysis (HD) patients.

METHODS

A total of 109 HD patients and 31 healthy controls were enrolled in the study from September 2014 to December 2014. We evaluated the abdominal aortic calcification (AAC) score by plain X-ray films of the abdomen and measured serum YKL-40 concentrations using enzyme-linked immunosorbent assay. We also examined the relationship between YKL-40 levels and AAC scores in HD patients.

RESULTS

Serum YKL-40 levels in HD patients were significantly higher than those in healthy controls [199.8 (144.8, 288.7) vs. 71.9 (52.8, 89.3) ng/ml; P < 0.001]. There was a tendency that YKL-40 levels in diabetic hemodialysis patients were higher than those in nondiabetic patients [217.8 (155.3, 335.8) vs. 192.9 (135.9, 274.4) ng/ml; P = 0.093]. A significant positive correlation was found between serum YKL-40 level and AAC score in these patients (r = 0.410, P = 0.003). Multiple regression analysis showed that Ln(YKL-40) was independently associated with AAC score in HD patients (P = 0.044).

CONCLUSION

This study showed high serum YKL-40 concentrations in chronic HD patients and that YKL-40 was independently associated with increased AAC in hemodialysis patients.

Urinary biomarkers in kidney disease

BACKGROUND

Chronic kidney disease (CKD) affects many people worldwide and early diagnosis is essential for successful treatment and improved outcome. Unfortunately, current methods are insufficient especially for early disease detection. However, advances in the analytical methods for urinary biomarkers may provide a unique opportunity for diagnosis and management of CKD. This review explores evolving technology and highlights the importance of early marker detection in these patients.

APPROACH

A search strategy was set up using the terms CKD, biomarkers, and urine. The search included 53 studies comprising 37 biomarkers. The value of these biomarkers for CKD are based on their ability to diagnose CKD, monitor progression, assess mortality and nephrotoxicity.

RESULTS

KIM-1 was the best marker for diagnosis as it increased with the development of incident CKD. DKK3 increased in patients with declining eGFR, whereas UMOD decreased in those with declining kidney function. Unfortunately, none fulfilled all criteria to adequately assess mortality and nephrotoxicity.

CONCLUSION

New developments in the field of urinalysis using smart toilets may open several possibilities for urinary biomarkers. This review explored which biomarkers could be used for CKD disease detection and management.

Urinary Biomarkers and Kidney Injury in VA NEPHRON-D: Phenotyping Acute Kidney Injury in Clinical Trials

RATIONALE & OBJECTIVE

Urinary biomarkers of injury, inflammation, and repair may help phenotype acute kidney injury (AKI) observed in clinical trials. We evaluated the differences in biomarkers between participants randomized to monotherapy or to combination renin-angiotensin-aldosterone system (RAAS) blockade in VA NEPHRON-D, where an increased proportion of observed AKI was acknowledged in the combination arm.

STUDY DESIGN

Longitudinal analysis.

SETTING & PARTICIPANTS

A substudy of the VA NEPHRON-D trial.

PREDICTOR

Primary exposure was the treatment arm (combination [RAAS inhibitor] vs monotherapy). AKI is used as a stratifying variable.

OUTCOME

Urinary biomarkers, including albumin, EGF (epidermal growth factor), MCP-1 (monocyte chemoattractant protein-1), YKL-40 (chitinase 3-like protein 1), and KIM-1 (kidney injury molecule-1).

ANALYTICAL APPROACH

Biomarkers measured at baseline and at 12 months in trial participants were compared between treatment groups and by AKI. AKI events occurring during hospitalization were predefined safety end points in the original trial. The results were included in a meta-analysis with other large chronic kidney disease trials to assess global trends in biomarker changes.

RESULTS

In 707 participants followed for a median of 2.2 years, AKI incidence was higher in the combination (20.7%) versus the monotherapy group (12.7%; relative risk [RR], 1.64 [95% CI, 1.16-2.30]). Compared with the monotherapy arm, in the combination arm the urine biomarkers at 12 months were either unchanged (MCP-1: RR, -3% [95% CI, -13% to 9%], Padj=0.8; KIM-1: RR, -10% [95% CI, -20% to 1%], Padj=0.2; EGF, RR-7% [95% CI, -12% to-1%], Padj=0.08) or lower (albuminuria: RR, -24% [95% CI, -37% to-8%], Padj=0.02; YKL: RR, -40% to-44% [95% CI, -58% to-25%], Padj<0.001). Pooled meta-analysis demonstrated reduced albuminuria in the intervention arm across 3 trials and similar trajectories in other biomarkers.

LIMITATIONS

Biomarker measurement was limited to 2 time points independent of AKI events.

CONCLUSIONS

Despite the increased risk of serum creatinine-defined AKI, combination RAAS inhibitor therapy was associated with unchanged or decreased urinary biomarkers at 12 months. This suggests a possible role for kidney biomarkers to further characterize kidney injury in clinical trials.

PLAIN-LANGUAGE SUMMARY

The VA NEPHRON-D trial investigated inhibition of the renin-angiotensin-aldosterone system (RAAS) hormonal axis on kidney outcomes in a large population of diabetic chronic kidney disease patients. The trial was stopped early due to increased events of serum creatinine-defined acute kidney injury in the combination therapy arm. Urine biomarkers can serve as an adjunct to serum creatinine in identifying kidney injury. We found that urinary biomarkers in the combination therapy group were not associated with a pattern of harm and damage to the kidney, despite the increased number of kidney injury events in that group. This suggests that serum creatinine alone may be insufficient for defining kidney injury and supports further exploration of how other biomarkers might improve identification of kidney injury in clinical trials.

The 2021 KDIGO blood pressure target and the progression of chronic kidney disease: Findings from KNOW-CKD

BACKGROUND

The 2021 Kidney Disease: Improving Global Outcomes (KDIGO) clinical practice guideline for the management of blood pressure (BP) in chronic kidney disease (CKD) recommends a target systolic BP of <120 mmHg as this target can provide cardiovascular benefits. However, it remains unclear whether implementing the new BP target could improve kidney outcomes.

METHODS

The association between the 2021 KDIGO BP target and CKD progression was examined and compared with the 2012 KDIGO BP target among 1724 participants included in the KoreaN Cohort Study for Outcomes in Patients With CKD. The main exposure was the BP status categorized according to the 2012 or 2021 KDIGO guideline: (1) controlled within the 2021 target, (2) controlled within the 2012 target only, and (3) above both targets. The primary outcome was a composite kidney outcome of ≥50% decline in the estimated glomerular filtration rate from baseline or the initiation of kidney replacement therapy during the follow-up period.

RESULTS

Composite kidney outcomes occurred in 650 (37.7%) participants during the 8078 person-years of follow-up (median, 4.9 years). The incidence rates of this outcome were 55, 66.5, and 116.4 per 1000 person-years in BP controlled within the 2021 and 2012 KDIGO targets, and BP above both targets, respectively. In the multivariable cause-specific hazard model, hazard ratios for the composite outcome were 0.76 (95% confidence interval (CI), 0.60-0.95) for BP controlled within the 2021 target and 1.36 (95% CI, 1.13-1.64) for BP above both targets, compared with BP controlled within 2012 target only.

CONCLUSION

The newly lowered BP target by the 2021 KDIGO guideline was associated with improved kidney outcome compared with BP target by the 2012 KDIGO guideline.

Acute Declines in Estimated GFR in Blood Pressure Target Trials and Risk of Adverse Outcomes

RATIONALE & OBJECTIVE

Acute decreases in glomerular filtration rate (GFR) occur commonly during intensive blood pressure (BP) lowering. Our objective was to determine the relationship between acute decreases in estimated GFR and patient outcomes.

STUDY DESIGN

Retrospective observational study.

SETTING & PARTICIPANTS

Participants from 4 randomized controlled trials of intensive BP lowering in chronic kidney disease (Modification of Diet in Renal Disease study, African American Study of Kidney Disease and Hypertension, Systolic Blood Pressure Intervention Trial, and Action to Control Cardiovascular Risk in Diabetes trial).

EXPOSURE

A 4-category exposure defined by the level of acute decrease in estimated GFR (defined as>15% vs≤15% between baseline and month 4) and the randomization to intensive versus usual BP control.

OUTCOMES

Risk of kidney replacement therapy (primary outcome), defined as the need for dialysis or transplant except in the Action to Control Cardiovascular Risk in Diabetes trial, which defined its kidney outcome as a composite occurrence of serum creatinine concentration>3.3mg/dL, kidney failure, or kidney replacement therapy.

ANALYTICAL APPROACH

Multivariable Cox models.

RESULTS

We included 4,473 individuals randomly assigned to intensive versus usual BP control who had a total of 351 kidney outcomes and 304 deaths during median follow-up durations of 22 and 24 months, respectively. Approximately 14% of participants exhibited an acute decrease in eGFR, 11.0% in the usual BP treatment arm and 17.8% in the intensive BP treatment arm. In adjusted models, compared with a≤15% eGFR decrease in the usual BP arm, a≤15% eGFR decrease in the intensive BP control arm was associated with lower risk of the kidney outcome (HR, 0.75; 95% CI, 0.57-0.98). In contrast, a>15% decrease in eGFR was associated with a higher risk of the kidney outcome in the usual (HR, 2.47; 95% CI, 1.80-3.38) and intensive BP treatment arms (HR, 1.99; 95% CI, 1.45-2.73) compared with a≤15% decrease in the usual BP arm.

LIMITATIONS

Observational study, residual confounding.

CONCLUSIONS

Decreases in eGFR of>15% in the usual and intensive BP treatment arms were associated with a higher risk of kidney outcomes compared with a≤15% decrease in the usual BP arm and may be a harbinger of adverse outcomes.

Effects of Intensive Systolic Blood Pressure Lowering on End-Stage Kidney Disease and Kidney Function Decline in Adults With Type 2 Diabetes Mellitus and Cardiovascular Risk Factors: A Post Hoc Analysis of ACCORD-BP and SPRINT

OBJECTIVE

To determine the effects of intensive systolic blood pressure (SBP) lowering on the risk of major adverse kidney outcomes in people with type 2 diabetes mellitus (T2DM) and/or prediabetes and cardiovascular risk factors.

RESEARCH DESIGN AND METHODS

This post hoc ACCORD-BP subgroup analysis included participants in the standard glucose-lowering arm with cardiovascular risk factors required for SPRINT eligibility. Cox proportional hazards regression models compared the hazard for the composite of dialysis, kidney transplant, sustained estimated glomerular filtration rate (eGFR) <15 mL/min/1.73 m2, serum creatinine >3.3 mg/dL, or a sustained eGFR decline ≥57% between the intensive (<120 mmHg) and standard (<140 mmHg) SBP-lowering arms.

RESULTS

The study cohort included 1,966 SPRINT-eligible ACCORD-BP participants (40% women) with a mean age of 63 years. The mean SBP achieved after randomization was 120 ± 14 and 134 ± 15 mmHg in the intensive and standard arms, respectively. The kidney composite outcome occurred at a rate of 9.5 and 7.2 events per 1,000 person-years in the intensive and standard BP arms (hazard ratio [HR] 1.35 [95% CI 0.85-2.14]; P = 0.20). Intensive SBP lowering did not affect the risk of moderately (HR 0.96 [95% CI 0.76-1.20]) or severely (HR 0.92 [95% CI 0.66-1.28]) increased albuminuria. Including SPRINT participants with prediabetes in the cohort did not change the overall results.

CONCLUSIONS

This post hoc subgroup analysis suggests that intensive SBP lowering does not increase the risk of major adverse kidney events in individuals with T2DM and cardiovascular risk factors.

Markers of Kidney Tubular Function Deteriorate While Those of Kidney Tubule Health Improve in Primary Aldosteronism After Targeted Treatments

Background Targeted treatment with mineralocorticoid receptor antagonists (MRAs) or adrenalectomy in patients with primary aldosteronism (PA) causes a decline in estimated glomerular filtration rate; however, the associated simultaneous changes in biomarkers of kidney tubule health still remain unclear. Methods and Results We matched 104 patients with newly diagnosed unilateral PA who underwent adrenalectomy with 104 patients with unilateral PA who were treated with MRAs, 104 patients with bilateral PA treated with MRAs, and 104 patients with essential hypertension who served as controls. Functional biomarkers were measured before the targeted treatment and 1 year after treatment, including serum markers of kidney function (cystatin C, creatinine), urinary markers of proximal renal tubular damage (L-FABP [liver-type fatty-acid binding protein], KIM-1 [kidney injury molecule-1]), serum markers of kidney tubular reserve and mineral metabolism (intact parathyroid hormone), and proteinuria. Compared with the patients with essential hypertension, the patients with PA had higher pretreatment serum intact parathyroid hormone and urinary creatinine-corrected parameters, including L-FABP, KIM-1, and albumin. The patients with essential hypertension and with PA had similar cystatin C levels. After treatment with MRAs or adrenalectomy of unilateral PA and MRAs of bilateral PA, the patients with PA had increased serum cystatin C and decreased urinary L-FABP/creatinine, KIM-1/creatinine, creatinine-based estimated glomerular filtration rate, intact parathyroid hormone, and proteinuria (all P<0.05). In multivariable regression models, a higher urinary L-FABP/creatinine ratio and older age were significantly correlated with the occurrence of kidney failure (estimated glomerular filtration rate dip ≥30%) in the patients with PA after targeted treatment. Conclusions Compared with the matched patients with essential hypertension, the incident patients with PA at diagnosis had higher levels of several biomarkers, including markers of kidney damage, tubular reserve/mineral metabolism, and proteinuria. Functional kidney failure in the patients with PA after treatment could be predicted by a higher baseline urinary L-FABP/creatinine ratio and older age. After targeted treatments in the patients with bilateral or unilateral PA, these biomarkers of kidney tubule health were restored, but creatinine-based estimated glomerular filtration rate declined, which may therefore reflect hemodynamic changes rather than intrinsic damage to kidney tubular cells.

Trends in using of antihypertensive medication among US CKD adults, NHANES 2001-2018

Objective

Blood pressure (BP) control rates among adult patients taking antihypertensive medications in the United States have not improved over the last decade. Many CKD adults require more than one class of antihypertensive agent to reach the BP target recommended by the guidelines. However, no study has quantified the proportion of adult CKD patients taking antihypertensive medication who are on monotherapy or combination therapy.

Methods

National Health and Nutrition Examination Survey data during 2001-2018 was used, including adults with CKD taking antihypertensive medication (age ≥ 20 years, n = 4,453). BP control rates were investigated under the BP targets recommended by the 2021 KDIGO, the 2012 KDIGO, and the 2017 ACC/AHA guidelines.

Results

The percentages of uncontrolled BP among US adults with CKD taking antihypertensive medication were 81.4% in 2001-2006 and 78.2% in 2013-2018. The proportion of monotherapy of antihypertensive regimen were 38.6, 33.3, and 34.6% from 2001 to 2006, 2007-2012, and 2013-2018, with no obvious difference. Similarly, there was no significant change in percentages of dual-therapy, triple-therapy, and quadruple-therapy. Although proportion of CKD adults not treated with ACEi/ARB decreased from 43.5% in 2001-2006 to 32.7% in 2013-2018, treatment of ACEi/ARB among patients with ACR > 300 mg/g had no significant change.

Conclusion

The BP control rates among US adult CKD patients taking antihypertensive medications have not improved from 2001 to 2018. Mono-therapy accounted for about one third of adult CKD patients taking antihypertensive medication and not changed. Increasing antihypertensive medication combination therapy may help improve BP control in CKD adults in the United States.

Current status of the rapid decline in renal function due to diabetes mellitus and its associated factors: analysis using the National Database of Health Checkups in Japan

The increasing number of patients undergoing dialysis due to diabetes mellitus (DM) is causing serious economic problems, and its reduction is an urgent policy issue in developed countries, including Japan. We aimed to assess the association between the annual rapid decline in renal function and health checkup measures, including blood pressure, to identify health guidance targets for preventing diabetic nephropathy (DN) and diabetic kidney disease (DKD) among individuals in a medical checkup system ("Tokuteikenshin" program) in 2018. This longitudinal analysis included 3,673,829 individuals who participated in the "Tokuteikenshin" program in 2018, had hemoglobin A1c (HbA1c) levels ≥5.6%, were available for follow-up, and underwent estimated glomerular filtration rate (eGFR) evaluation. We estimated the incidence of the relative annual decrease in eGFR ≥10% per 1000 person-years and odds ratios to evaluate the rapid decline in renal function and determine health guidance goals and their role in preventing DN and DKD. Overall, 20.83% of patients with DM had a rapid decline in renal function within the observation period. A rapid decline in renal function was associated with high systolic blood pressure, poor or strict DM control, increased urinary protein excretion, and decreased blood hemoglobin levels. The incidence of rapid decline in renal function is higher in DM, and appropriate systolic blood pressure and glycemic control are important to prevent the progression to DN or DKD. Our findings will be useful for researchers, clinicians, and other public health care members in establishing effective health guidance and guidelines for CKD prevention.

Biomarkers: Promising and valuable tools towards diagnosis, prognosis and treatment of Covid-19 and other diseases

The use of biomarkers as early warning systems in the evaluation of disease risk has increased markedly in the last decade. Biomarkers are indicators of typical biological processes, pathogenic processes, or pharmacological reactions to therapy. The application and identification of biomarkers in the medical and clinical fields have an enormous impact on society. In this review, we discuss the history, various definitions, classifications, characteristics, and discovery of biomarkers. Furthermore, the potential application of biomarkers in the diagnosis, prognosis, and treatment of various diseases over the last decade are reviewed. The present review aims to inspire readers to explore new avenues in biomarker research and development.

Blood Pressure Control in Patients with Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the most common cause of end-stage kidney disease. Blood pressure (BP) control can reduce the risks of cardiovascular (CV) morbidity, mortality, and kidney disease progression. Recently, the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines have suggested the implementation of a more intensive BP control with a target systolic BP (SBP) of <120 mmHg based on the evidence that the CV benefits obtained is outweighed by the kidney injury risk associated with a lower BP target. However, an extremely low BP level may paradoxically aggravate renal function and CV outcomes. Herein, we aimed to review the existing literature regarding optimal BP control using medications for DKD.

Absence of long-term changes in urine biomarkers after AKI: findings from the CRIC study

BACKGROUND

Mechanisms by which AKI leads to CKD progression remain unclear. Several urine biomarkers have been identified as independent predictors of progressive CKD. It is unknown whether AKI may result in long-term changes in these urine biomarkers, which may mediate the effect of AKI on CKD progression.

METHODS

We selected 198 episodes of hospitalized AKI (defined as peak/nadir inpatient serum creatinine values ≥ 1.5) among adult participants in the Chronic Renal Insufficiency Cohort (CRIC) Study. We matched the best non-AKI hospitalization (unique patients) for each AKI hospitalization using pre-hospitalization characteristics including eGFR and urine protein/creatinine ratio. Biomarkers were measured in banked urine samples collected at annual CRIC study visits.

RESULTS

Urine biomarker measurements occurred a median of 7 months before and 5 months after hospitalization. There were no significant differences in the change in urine biomarker-to-creatinine ratio between the AKI and non-AKI groups: KIM-1/Cr + 9% vs + 7%, MCP-1/Cr + 4% vs + 1%, YKL-40/Cr + 7% vs -20%, EGF/Cr -11% vs -8%, UMOD/Cr -2% vs -7% and albumin/Cr + 17% vs + 13% (all p > 0.05).

CONCLUSION

In this cohort of adults with CKD, AKI did not associate with long-term changes in urine biomarkers.

Renin-Angiotensin System Inhibitors in Patients With COVID-19: A Meta-Analysis of Randomized Controlled Trials Led by the International Society of Hypertension

Background

Published randomized controlled trials are underpowered for binary clinical end points to assess the safety and efficacy of renin‐angiotensin system inhibitors (RASi) in adults with COVID‐19. We therefore performed a meta‐analysis to assess the safety and efficacy of RASi in adults with COVID‐19.

Methods and Results

MEDLINE, EMBASE, ClinicalTrials.gov, and the Cochrane Controlled Trial Register were searched for randomized controlled trials that randomly assigned patients with COVID‐19 to RASi continuation/commencement versus no RASi therapy. The primary outcome was all‐cause mortality at ≤30 days. A total of 14 randomized controlled trials met the inclusion criteria and enrolled 1838 participants (aged 59 years, 58% men, mean follow‐up 26 days). Of the trials, 11 contributed data. We found no effect of RASi versus control on all‐cause mortality (7.2% versus 7.5%; relative risk [RR], 0.95; [95% CI, 0.69–1.30]) either overall or in subgroups defined by COVID‐19 severity or trial type. Network meta‐analysis identified no difference between angiotensin‐converting enzyme inhibitors versus angiotensin II receptor blockers. RASi users had a nonsignificant reduction in acute myocardial infarction (2.1% versus 3.6%; RR, 0.59; [95% CI, 0.33–1.06]), but increased risk of acute kidney injury (7.0% versus 3.6%; RR, 1.82; [95% CI, 1.05–3.16]), in trials that initiated and continued RASi. There was no increase in need for dialysis or differences in congestive cardiac failure, cerebrovascular events, venous thromboembolism, hospitalization, intensive care admission, inotropes, or mechanical ventilation.

Conclusions

This meta‐analysis of randomized controlled trials evaluating angiotensin‐converting enzyme inhibitors/angiotensin II receptor blockers versus control in patients with COVID‐19 found no difference in all‐cause mortality, a borderline decrease in myocardial infarction, and an increased risk of acute kidney injury with RASi. Our findings provide strong evidence that RASi can be used safely in patients with COVID‐19.

Blood pressure and kidney outcomes in patients with severely decreased glomerular filtration rate: a nationwide observational cohort study

OBJECTIVES

To investigate the association between blood pressure (BP) and kidney outcomes in patients with estimated glomerular filtration rate less than 30 ml/min per 1.73 m 2 and different degrees of albuminuria.

METHODS

National observational cohort study of 18 071 chronic kidney disease (CKD) stage 4-5 patients in routine nephrology care 2010-2017. The association between both baseline and repeated clinic office BP and eGFR slope and kidney replacement therapy (KRT) was explored using multivariable adjusted joint models. The analyses were stratified on albuminuria at baseline.

RESULTS

The adjusted yearly eGFR slope became increasingly steeper from -0,91 (95% CI -0.83 to -1.05) ml/min per 1.73 m 2 per year in those with SBP less than 120 mmHg at baseline to -2.09 (-1.83 to -2.37) ml/min per 1.73 m 2 in those with BP greater than 160 mmHg. Similarly, eGFR slope was steeper with higher DBP. Lower SBP and DBP was associated with slower eGFR decline in patients with albuminuria grade A3 (>30 mg/mmol) but not consistently in albuminuria A1-A2. Those with diabetes progressed faster and the association between BP and eGFR slope was stronger. In repeated BP measurement analyses, every 10 mmHg higher SBP over time was associated with 39% additional risk of KRT.

CONCLUSION

In people with eGFR less than 30 ml/min per 1.73 m 2 , lower clinic office BP is associated with more favorable kidney outcomes. Our results support lower BP targets also in people with CKD stage 4-5.

Serum YKL-40 Level is Associated with Geriatric Nutritional Risk Index (GNRI) and γ-GTP in Hemodialysis Patients

Chitinase-3-like protein 1 (YKL-40) is a glycoprotein associated with inflammation and tissue remodeling that has recently been used as a marker of inflammation in hemodialysis (HD) patients. In this study, we aimed to determine whether YKL-40 has potential to serve as a nutritional parameter in Japanese HD patients. The serum YKL-40 concentration, hematological parameters, inflammatory marker levels, anthropometric measurements, and laboratory values were measured in 88 patients receiving HD. The geriatric nutritional risk index (GNRI) was used as a nutritional assessment tool. 45.4% of patients were malnourished. YKL-40 correlated positively with age, alkaline phosphatase, alanine transaminase and γ-glutamyl transpeptidase (γ-GTP) levels, but not with nutritional status, and correlated inversely with ankle brachial index score, a predictor of atherosclerosis. Furthermore, multiple regression analysis confirmed that γ-GTP, GNRI and age correlated with YKL-40. YKL-40 elevation was associated with γ-GTP, GNRI and age in HD patients. J. Med. Invest. 69 : 101-106, February, 2022.

The Prevalence, Progress and Risk Factor Control of Chronic Kidney Disease in Chinese Adults With Type 2 Diabetes Mellitus in Primary Care

OBJECTIVE

This study aimed to evaluate the prevalence of chronic kidney disease (CKD) in Chinese adults with T2DM in primary care, and the association of HbA_1c, blood pressure (BP) and triglycerides (TG), i.e. ABC control at follow up (FU) with the progress and regression of CKD.

METHODS

A total of 5123 patients with ≥3 measurements of estimated glomerular filtration rate (eGFR), urinary albumin-to-creatinine ratio (UACR), HbA_1c, BP, LDL-C and TG, and FU ≥ 12 months were included into final analysis. The presence of CKD was defined as the presence of albuminuria (UACR ≥ 30 mg/g), impaired eGFR (eGFR < 60 ml/min/1.73 m²) or both, and was categorised as low, moderate and high/very high risk. The change of CKD risk for outcome was categorised as stable (no change), progress (risk increase) and regress (risk decrease) from baseline to the last visits (LV).

RESULTS

The prevalence of CKD, impaired eGFR and albuminuria was 29.6%, 5.8% and 27.1% at baseline, with 70.4%, 20.3%, 7.0% and 2.3% of patients distributed in low, moderate, high and very high risk group. There were 3457 (67.5%), 1120 (21.8%) and 546 (10.7%) patients had CKD outcome risk stable, progressed and regressed respectively. The proportion of patients reaching targets of BP ≤ 130/80 mmHg, HbA_1c<7.5%, LDL-C<2.60 mmol/L increased from baseline to FU and LV, together with increased usage of insulin, RAS inhibitors and lipid lowering medications. After multivariable adjustment, the HbA_1c<7.5% (OR: 0.66, 95%CI 0.56-0.78), TG< 1.7 mmol/L (OR: 0.81, 95%CI 0.68-0.96) at FU and BP ≤ 130/80 mmHg at LV (OR: 0.82, 95%CI 0.70-0.95) was negatively associated with CKD outcome risk progress.

CONCLUSION

The prevalence of CKD was high with 21.8% of patients progressing to higher CKD outcome risk at FU, attention should be paid on long term and better ABC control.

Chronic Kidney Disease and SGLT2 Inhibitors: A Review of the Evolving Treatment Landscape

There is currently an unmet need for effective treatment of chronic kidney disease (CKD) that slows disease progression, prevents development of end-stage kidney disease and cardiovascular disease, and prolongs survival of patients with CKD. In the last 20 years, the only agents to show a reduction in the risk of CKD progression in patients with and without type 2 diabetes (T2D) were angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, but neither drug class has provided a decreased risk of all-cause mortality in patients with CKD and evidence for their use in patients with CKD without T2D is relatively limited. This review discusses the mechanisms underlying the progression of CKD, its associated risk factors, and summarizes the potential therapeutic approaches for managing CKD. There is increasing evidence to support the role of sodium–glucose cotransporter 2 (SGLT2) inhibitor therapy in patients with CKD, including data from the designated kidney outcome trials in patients with T2D (CREDENCE) and in patients with or without T2D (DAPA-CKD). These studies showed a significant reduction in the risk of CKD progression with canagliflozin (in patients with T2D) or dapagliflozin (in patients with or without T2D), respectively, with DAPA-CKD being the first trial to show a reduced risk of all-cause mortality. On the basis of these data, individualized treatment with SGLT2 inhibitors represents a promising therapeutic option for patients with diabetic and nondiabetic CKD to slow disease progression.

Chronic kidney disease is a common condition in which the ability of the kidneys to work correctly gradually decreases over time. It is a major risk factor for a number of other serious conditions, including cardiovascular disease and end-stage kidney disease, and for early death. Several treatments have been shown to reduce the risk of chronic kidney disease progressing (particularly in patients with type 2 diabetes), but there have been no treatments that slow chronic kidney disease progression, prevent the development of end-stage kidney disease and cardiovascular disease, and prolong survival. However, evidence is now accumulating to suggest that some drugs initially developed to treat other diseases may be potential treatments for chronic kidney disease. The sodium–glucose cotransporter 2 inhibitors, which are commonly used to lower blood sugar levels in people with type 2 diabetes, are examples of such drugs. Data from two studies of sodium–glucose cotransporter 2 inhibitors—the CREDENCE study of canagliflozin in patients with chronic kidney disease and type 2 diabetes and the DAPA-CKD study of dapagliflozin in patients with chronic kidney disease with or without type 2 diabetes—have shown that these drugs reduce the risk of chronic kidney disease progression in these patients. More importantly, the DAPA-CKD study showed that patients with chronic kidney disease who were taking dapagliflozin had a reduced risk of death compared with placebo. These results show that sodium–glucose cotransporter 2 inhibitors are slowing the progression of chronic kidney disease and improve overall outcomes for properly selected patients.

Lower ambulatory nocturnal SBP is associated with less cardiovascular and renal damage in normotensive hospitalized patients with chronic kidney disease

OBJECTIVE

The impact of nocturnal blood pressure (BP) on target organ damage (TOD) in chronic kidney disease (CKD) patients with normotension has not been established. In this study, we determined whether nocturnal BP is correlated with cardiovascular and renal damage independent of the 24-h BP in CKD patients with normotension or hypertension.

METHODS

A total of 1166 hospitalized patients with CKD not requiring dialysis were enrolled in this cross-sectional study, 421 and 745 of whom had normotension and hypertension, respectively. TOD was assessed by the left ventricular mass index (LVMI), estimated glomerular filtration rate (eGFR) and presence of proteinuria. Univariate and multivariable regression analyses were used to evaluate the relationships between nocturnal BP and TOD.

RESULTS

In the multivariable-adjusted models, including the 24-h BP, nocturnal SBP was independently associated with the LVMI, eGFR and proteinuria in patients with normotension (P < 0.05), while the nocturnal DBP was not correlated with proteinuria. The nocturnal SBP was associated with LVMI and proteinuria, but not the eGFR in patients with hypertension. We did not demonstrate an association between nocturnal DBP and TOD in these patients. When nocturnal SBP in patients with normotension was further divided into tertiles [tertile 1 (<104 mmHg), tertile 2 (104-114 mmHg) and tertile 3 (≥114 mmHg)], multivariate analysis showed that tertile 3 was independently associated with TOD.

CONCLUSION

Nocturnal SBP was shown to be an independent risk factor for TOD in patients with normotension. Targeting a nocturnal ambulatory SBP to less than 114 mmHg or even less than 104 mmHg may help prevent TOD in patients with CKD.

The Promise of Tubule Biomarkers in Kidney Disease: A Review

For over 70 years, serum creatinine has remained the primary index for detection and monitoring of kidney disease. Tubulointerstitial damage and fibrosis are highly prognostic for subsequent kidney failure in biopsy studies, yet this pathology is invisible to the clinician in the absence of a biopsy. Recent discovery of biomarkers that reflect distinct aspects of kidney tubule disease have led to investigations of whether these markers can provide additional information on risk of chronic kidney disease (CKD) progression and associated adverse clinical end points, above and beyond estimated glomerular filtration rate and albuminuria. These biomarkers can be loosely grouped into those that mark tubule cell injury (eg, kidney injury molecule 1, monocyte chemoattractant protein 1) and those that mark tubule cell dysfunction (eg, α1-microglobulin, uromodulin). These kidney tubule biomarkers provide new opportunities to monitor response to therapeutics used to treat CKD patients. In this review, we describe results from some unique contributions in this area and discuss the current challenges and requirements in the field to bring these markers to clinical practice. We advocate for a broader assessment of kidney health that moves beyond a focus on the glomerulus, and we highlight how such tools can improve diagnostic accuracy and earlier assessment of therapeutic efficacy or harm in CKD patients.

Blood pressure control in patients with chronic kidney disease

Uncontrolled blood pressure (BP) in patients with chronic kidney disease (CKD) can lead to serious adverse outcomes. To prevent the occurrence of cardiovascular events (CVEs), and end-stage kidney disease, achieving an optimal BP level is important. Recently, there has been a paradigm shift in the management of BP largely as a result of the Systolic Blood Pressure Intervention Trial (SPRINT), which showed a reduction in CVEs by lowering systolic BP to 120 mmHg. A lower systolic blood pressure (SBP) target has been accepted by the Kidney Disease: Improving Global Outcomes (KDIGO) 2021 guidelines. However, whether intensive control of SBP targeting < 120 mmHg is also effective in patients with CKD is controversial. Notably, this lower target SBP is associated with a higher risk of adverse kidney outcomes. Unfortunately, there have been no randomized controlled trials on this issue involving only patients with CKD, particularly those with advanced CKD. In this review, we discuss the optimal control of BP in patients with CKD in terms of reduction in death and CVEs as well as attenuation of CKD progression based on the evidence-based literature.

Guideline-Driven Management of Hypertension: An Evidence-Based Update

Several important findings bearing on the prevention, detection, and management of hypertension have been reported since publication of the 2017 American College of Cardiology/American Heart Association Blood Pressure Guideline. This review summarizes and places in context the results of relevant observational studies, randomized clinical trials, and meta-analyses published between January 2018 and March 2021. Topics covered include blood pressure measurement, patient evaluation for secondary hypertension, cardiovascular disease risk assessment and blood pressure threshold for drug therapy, lifestyle and pharmacological management, treatment target blood pressure goal, management of hypertension in older adults, diabetes, chronic kidney disease, resistant hypertension, and optimization of care using patient, provider, and health system approaches. Presenting new information in each of these areas has the potential to increase hypertension awareness, treatment, and control which remain essential for the prevention of cardiovascular disease and mortality in the future.

Renal outcomes and blood pressure patterns in diabetic and nondiabetic individuals at high cardiovascular risk

BACKGROUND

Diabetes and hypertension are risk factors for renal and cardiovascular outcomes. Data on the association of achieved blood pressure (BP) with renal outcomes in patients with and without diabetes are sparse. We investigated the association of achieved SBP, DBP with renal outcomes and urinary albumin excretion (UAE) in people with vascular disease.

METHODS

In this pooled analysis, we assessed renal outcome data from high-risk patients aged 55 years or older with a history of cardiovascular disease, 70% of whom had hypertension, randomized to The Ongoing Telmisartan Alone and in Combination with Ramipril Global Endpoint Trial and to Telmisartan Randomized Assessment Study in ACE Intolerant Subjects with Cardiovascular Disease trials investigating telmisartan, ramipril and their combination with a median follow-up of 56 months. Standardized office BP was measured every 6 months, estimated glomerular filtration rate (eGFR) and UAE at baseline, 2 years and study end. Associations of mean achieved BP on treatment were investigated on major renal outcomes including end-stage renal disease (ESRD), decline of eGFR by at least 40%, doubling of creatinine and the composites thereof and on UAE. Analyses were by Cox regression analysis, analysis of variance and Chi2-test. Of 30 937 patients with complete data, 19 450 patients without and 11 487 with diabetes were enrolled between 1 December 2001 and 31 July 2003 and followed until 31 July 2008. Data were pooled as the outcomes for telmisartan 80 mg/day (n = 2903) or placebo (n = 2907) for Telmisartan Randomized Assessment Study in ACE Intolerant Subjects with Cardiovascular Disease and ramipril 10 mg/day (n = 8407), telmisartan 80 mg/day (n = 8386) or the combination of both (n = 8334) were similar.

RESULTS

For both those with and without diabetes, the hazard ratios for the composites ESRD or doubling of serum creatinine (707 events overall) and ESRD or 40% eGFR loss (2371 events overall) reached a nadir at achieved SBP of 120 to less than 140 mmHg, and increased with higher and lower SBP with similar relative risk with or without diabetes. For example, risk for the former composite reached a hazard ratios 3.06 (confidence interval 1.90-4.92) with a mean achieved SBP more than 160 mmHg compared with 120 to less than 130 mmHg with diabetes and hazard ratios 2.14 (1.09-4.26) without diabetes. In contrast, the development of new microalbuminuria and macroalbuminuria (3002 and 846 events overall) associated linearly over the whole range of achieved SBP (apart from a slight increase in risk at SBP less than 120 mmHg only in those without diabetes). Absolute risks for the composite and albuminuria outcomes were consistently greater in those with diabetes as compared with without diabetes with high event rates over the whole SBP spectrum. The increased renal risk at low SBP was not related to a meaningful reduction of mandated study drugs or open label renin-angiotensin-aldosterone system inhibition.

CONCLUSION

In patients at high cardiovascular risk, SBP levels more than 140 mmHg and less than 120 are associated with increased risk for renal outcomes. Renal risk was greater in diabetes across the whole range of achieved SBP and DBP. These data suggest similar target BP range in patients with and without diabetes to prevent renal outcomes, a frequent complication in high-risk vascular patients.

CLINICAL TRIAL REGISTRATION

Clinical Trial registration: http://clinicaltrials.gov.Unique identifier: NCT00153101.

Association of Non-Steroidal Anti-Inflammatory Drugs with Kidney Health in Ambulatory Older Adults

BACKGROUND/OBJECTIVES

Non-steroidal anti-inflammatory drugs (NSAIDs) can cause kidney injury, especially in older adults. However, previously reported associations between NSAID use and kidney health outcomes are inconsistent and limited by reliance on serum creatinine-based GFR estimates. This analysis investigated the association of NSAID use with kidney damage in older adults using multiple kidney health measures.

DESIGN

Cross-sectional and longitudinal analyses.

SETTING

Multicenter, community-based cohort.

PARTICIPANTS

Two thousand nine hundred and ninty nine older adults in the Health ABC Study. A subcohort (n = 500) was randomly selected for additional biomarker measurements.

EXPOSURE

Prescription and over-the-counter NSAID use ascertained by self-report.

MEASUREMENTS

Baseline estimated glomerular filtration rate (eGFR) by cystatin C (cysC), urine albumin-to-creatinine ratio (ACR), kidney injury molecule-1 (KIM-1), and interleukin-18 (IL-18) were measured in 2,999 participants; alpha-1 microglobulin (α1m), neutrophil gelatinase-associated lipocalin (NGAL), propeptide type III procollagen (PIIINP), and uromodulin (UMOD) were measured in 500 participants. GFR was estimated three times over 10 years and expressed as percent change per year.

RESULTS

Participants had a mean age of 74 years, 51% were female, and 41% African-American. No eGFR differences were detected between NSAID users (n = 655) and non-users (n = 2,344) at baseline (72 ml/min/1.73 m² in both groups). Compared to non-users, NSAID users had lower adjusted odds of having ACR greater than 30 mg/g (0.67; 95% confidence interval (CI) = 0.51-0.89) and lower mean urine IL-18 concentration at baseline (-11%; 95% CI = -4% to -18%), but similar mean KIM-1 (5%; 95% CI = -5% to 14%). No significant differences in baseline concentrations of the remaining urine biomarkers were detected. NSAID users and non-users did not differ significantly in the rate of eGFR decline (-2.2% vs -2.3% per year).

CONCLUSION

Self-reported NSAID use was not associated with kidney dysfunction or injury based on multiple measures, raising the possibility of NSAID use without kidney harm in ambulatory older adults. More research is needed to define safe patterns of NSAID consumption.

Recent advances in managing primary hypertension

Hypertension remains a leading risk factor for cardiovascular mortality and morbidity globally despite the availability of effective and well-tolerated antihypertensive medications. Accumulating evidence suggests a more aggressive blood pressure regulation aimed at lower targets, particularly for selected patient groups. Our concepts of the optimal method for blood pressure measurement have radically changed, maintaining appropriate standard office measurements for initial assessment but relying on out-of-office measurement to better guide our decisions. Thorough risk stratification provides guidance in decision making; however, an individualized approach is highly recommended to prevent overtreatment. Undertreatment, on the other hand, remains a major concern and is mainly attributed to poor adherence and resistant or difficult-to-control forms of the disease. This review aims to present modern perspectives, novel treatment options, including innovative technological applications and developing interventional and pharmaceutical therapies, and the major concerns emerging from several years of research and epidemiological observations related to hypertension management.

Prevention of heart failure events with intensive versus standard blood pressure lowering across the spectrum of kidney function and albuminuria: a SPRINT substudy

AIMS

To determine whether a strategy of intensive blood pressure control reduces the risk of heart failure (HF) events consistently across the spectrum of kidney function and albuminuria.

METHODS AND RESULTS

SPRINT was a randomized clinical trial in which 9361 individuals ≥50 years, at high risk for or with cardiovascular disease, a systolic blood pressure of 130-180 mmHg, but without diabetes, were randomized to intensive (target <120 mmHg) vs. standard (target <140 mmHg) blood pressure control. We assessed whether estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (UACR) modified the effects of the blood pressure control strategy in reducing HF events (either hospitalization or emergency department visits) and the composite of HF events or cardiovascular death, using Cox proportional hazards regression and restricted cubic splines. Of the 9361 individuals included in SPRINT, eGFR and UACR were available for 9324 (99.6%) and 8913 (95.2%) subjects, respectively, including 2650 (28.4%) with eGFR <60 mL/min/1.73 m² and 248 (2.8%) with UACR >300 mg/g. During a median follow-up of 3.2 years (range 0-4.8 years), 160 (1.8%) participants had HF events and 233 (2.6%) had HF events or cardiovascular death. Risks of HF events or cardiovascular death increased from 0.42 (0.34-0.53) per 100 patient-years in patients with eGFR ≥60 mL/min/1.73 m² and UACR <30 mg/g to 4.55 (3.00-6.91) per 100 patient-years in patients with eGFR <60 mL/min/1.73 m² and UACR >300 mg/g. A similar gradient was observed for HF events alone. Both eGFR and UACR were independently, non-linearly associated with HF hospitalization and HF hospitalization or cardiovascular death (test for overall trend, P < 0.001). While the effects of intensive blood pressure control on HF event risk appeared to attenuate at lower eGFR and higher UACR, there was no significant interaction between eGFR or UACR and blood pressure control strategy (continuous and categorical interaction P > 0.05).

CONCLUSION

In SPRINT, eGFR and albuminuria were strong and additive determinants in forecasting HF risk. The effect of intensive blood pressure control in decreasing HF risk did not significantly vary across the spectrum of kidney function or albuminuria. Multidisciplinary pathways, incorporating blood pressure control, are needed for at-risk patients with chronic kidney disease to attenuate HF risk.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT01206062.

Intensive BP Control and eGFR Declines: Are These Events Due to Hemodynamic Effects and Are Changes Reversible?

PURPOSE OF REVIEW

Acute declines in estimated glomerular filtration rate (eGFR) are often observed during intensive blood pressure (BP) lowering. This review focuses on identifying the various mechanisms of eGFR decline associated with intensive BP lowering and evaluates the evidence linking BP control with kidney and cardiovascular (CV) outcomes.

RECENT FINDINGS

In 2017, the American College of Cardiology and the American Heart Association (ACC/AHA) began recommending treatment of all individuals to a BP target of < 130/80 mmHg. Since then, multiple post hoc analyses of BP trials have associated intensive BP lowering with acute declines in kidney function and acute kidney injury; whether these represent reversible changes in the kidney is still debated. There is ample evidence that intensive BP lowering is associated with declines in eGFR. The clinical implications of these events remain unclear. Individualizing the risks and benefits of intensive BP therapy continues to be warranted.

Effects of Intensive Blood Pressure Control in Patients with and without Albuminuria: Post Hoc Analyses from SPRINT

BACKGROUND AND OBJECTIVES

It is unclear whether the presence of albuminuria modifies the effects of intensive systolic BP control on risk of eGFR decline, cardiovascular events, or mortality.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The Systolic Blood Pressure Intervention Trial randomized nondiabetic adults ≥50 years of age at high cardiovascular risk to a systolic BP target of <120 or <140 mm Hg, measured by automated office BP. We compared the absolute risk differences and hazard ratios of ≥40% eGFR decline, the Systolic Blood Pressure Intervention Trial primary cardiovascular composite outcome, and all-cause death in those with or without baseline albuminuria (urine albumin-creatinine ratio ≥30 mg/g).

RESULTS

Over a median follow-up of 3.1 years, 69 of 1723 (4%) participants with baseline albuminuria developed ≥40% eGFR decline compared with 61 of 7162 (1%) participants without albuminuria. Incidence rates of ≥40% eGFR decline were higher in participants with albuminuria (intensive, 1.74 per 100 person-years; standard, 1.17 per 100 person-years) than in participants without albuminuria (intensive, 0.48 per 100 person-years; standard, 0.11 per 100 person-years). Although effects of intensive BP lowering on ≥40% eGFR decline varied by albuminuria on the relative scale (hazard ratio, 1.48; 95% confidence interval, 0.91 to 2.39 for albumin-creatinine ratio ≥30 mg/g; hazard ratio, 4.55; 95% confidence interval, 2.37 to 8.75 for albumin-creatinine ratio <30 mg/g; P value for interaction <0.001), the absolute increase in ≥40% eGFR decline did not differ by baseline albuminuria (incidence difference, 0.38 events per 100 person-years for albumin-creatinine ratio ≥30 mg/g; incidence difference, 0.58 events per 100 person-years for albumin-creatinine ratio <30 mg/g; P value for interaction =0.60). Albuminuria did not significantly modify the beneficial effects of intensive systolic BP lowering on cardiovascular events or mortality evaluated on relative or absolute scales.

CONCLUSIONS

Albuminuria did not modify the absolute benefits and risks of intensive systolic BP lowering.

Associations of Systolic Blood Pressure With Incident CKD G3-G5: A Cohort Study of South Korean Adults

RATIONALE & OBJECTIVE

Clinical practice guidelines recommend a target blood pressure (BP)<130/80 mm Hg to reduce cardiovascular risk. However, the optimal BP to prevent chronic kidney disease (CKD) is unknown.

STUDY DESIGN

Population-based retrospective cohort study.

SETTING & PARTICIPANTS

10.5 million adults who participated in the National Health Insurance Service National Health Checkup Program in South Korea between 2009 and 2015 and had an estimated glomerular filtration rate (GFR) ≥ 60 mL/min/1.73 m² at the beginning of follow-up.

PREDICTORS

Baseline and time-updated systolic BP (SBP) as a continuous variable and categorized as<110, 110 to 119, 120 to 129, 130 to 139, or≥140 mm Hg.

OUTCOME

Incident CKD GFR categories 3 to 5 (CKD G3-G5), defined as de novo development of estimated GFR<60 mL/min/1.73 m² for at least 2 consecutive assessments confirmed at least 90 days apart.

ANALYTICAL APPROACH

Cox proportional hazards regression for baseline BP and marginal structural analysis for time-updated BP.

RESULTS

During 49,169,311 person-years of follow-up, incident CKD G3-G5 developed in 172,423 (1.64%) individuals with a crude event rate of 3.51 (95% CI, 3.49-3.52) per 1,000 person-years. Compared to a baseline SBP of 120 to 129 mm Hg, HRs for incident CKD G3-G5 for the<110, 110 to 119, 130 to 139, and≥140 mm Hg categories were 0.84 (95% CI, 0.82-0.85), 0.92 (95% CI, 0.91-0.94), 1.11 (95% CI, 1.09-1.12), and 1.30 (95% CI, 1.28-1.31), respectively. For time-updated SBPs, corresponding HRs were 0.57 (95% CI, 0.56-0.59), 0.79 (95% CI, 0.78-0.80), 1.58 (95% CI, 1.55-1.60), and 2.49 (95% CI, 2.45-2.53), respectively. Treated as a continuous exposure, each 10-mm Hg higher SBP was associated with 35% higher risk for incident CKD G3-G5 (95% CI, 1.35-1.36).

LIMITATIONS

Use of International Classification of Diseases codes to assess comorbid condition burden; residual confounding, and potential selection bias cannot be excluded.

CONCLUSIONS

In this large national cohort study, higher SBPs were associated with higher risk for incident CKD G3-G5. These findings support evaluation of SBP-lowering strategies to reduce the development of CKD.

Benefits and Risks of Continuing Angiotensin-Converting Enzyme Inhibitors, Angiotensin II Receptor Antagonists, and Mineralocorticoid Receptor Antagonists during Hospitalizations for Acute Heart Failure

BACKGROUND

The renin-angiotensin-aldosterone axis plays a pivotal role in the pathophysiology of acute and chronic heart failure (HF) and represents an important target for guideline-directed medical therapy.

SUMMARY

The use of appropriate directed medical therapies for inhibition of the renin-angiotensin-aldosterone axis in chronic HF has been the subject of several landmark clinical trials, with high levels of adherence exhibited in the outpatient setting. However, less clarity exists with respect to the initiation, continuation, and cessation of renin-angiotensin-aldosterone system inhibitors (RAASi) in the setting of acute HF and exacerbation of HF necessitating hospitalization. In this review, we summarize relevant aspects of the physiology of the renin-angiotensin-aldosterone axis in acute HF and during decongestion. We also summarize the available evidence for the risks and benefits of initiating and continuing RAASi in acute HF. Key Message: We offer a decision-making pathway for the use of RAASi in the setting of acute HF that would help guide the cardiologist and nephrologist caring for patients with acute HF and cardiorenal syndrome.

Optimal blood pressure target and measurement in patients with chronic kidney disease

The prevalence rates of hypertension and chronic kidney disease (CKD) are increasing with the aging of the population. Hypertension and CKD are closely related, and hypertension with accompanying CKD is difficult to control. This difficulty controlling blood pressure (BP) can be explained by changes in diurnal variation in BP, such as non-dipping and reverse dipping patterns, increased pulse pressure, and BP variability in CKD patients resulting in a high frequency of nocturnal hypertension or masked hypertension. CKD patients with uncontrolled or nocturnal hypertension are at increased risk for cardiovascular disease, progression of CKD, and all-cause death. Recent studies have shown that intensive reduction of systolic BP below 120 mmHg is seems to favor in CKD patients regardless of the presence or absence of diabetes. As BP control is difficult in patients with CKD, appropriate measurement of BP is important. Automated BP monitoring could reduce the so-called "white coat effect" (spike in BP) that may be triggered by measurement in a clinical setting. Moreover, out-of-office BP monitoring at home or ambulatory BP monitoring for 24 hours may provide critical information regarding diurnal BP variability and nocturnal BP in patients with CKD.

Biomarkers in Stress Related Diseases/Disorders: Diagnostic, Prognostic, and Therapeutic Values

Various internal and external factors negatively affect the homeostatic equilibrium of organisms at the molecular to the whole-body level, inducing the so-called state of stress. Stress affects an organism's welfare status and induces energy-consuming mechanisms to combat the subsequent ill effects; thus, the individual may be immunocompromised, making them vulnerable to pathogens. The information presented here has been extensively reviewed, compiled, and analyzed from authenticated published resources available on Medline, PubMed, PubMed Central, Science Direct, and other scientific databases. Stress levels can be monitored by the quantitative and qualitative measurement of biomarkers. Potential markers of stress include thermal stress markers, such as heat shock proteins (HSPs), innate immune markers, such as Acute Phase Proteins (APPs), oxidative stress markers, and chemical secretions in the saliva and urine. In addition, stress biomarkers also play critical roles in the prognosis of stress-related diseases and disorders, and therapy guidance. Moreover, different components have been identified as potent mediators of cardiovascular, central nervous system, hepatic, and nephrological disorders, which can also be employed to evaluate these conditions precisely, but with stringent validation and specificity. Considerable scientific advances have been made in the detection, quantitation, and application of these biomarkers. The present review describes the current progress of identifying biomarkers, their prognostic, and therapeutic values.

Biomarkers in Stress Related Diseases/Disorders: Diagnostic, Prognostic, and Therapeutic Values

Various internal and external factors negatively affect the homeostatic equilibrium of organisms at the molecular to the whole-body level, inducing the so-called state of stress. Stress affects an organism's welfare status and induces energy-consuming mechanisms to combat the subsequent ill effects; thus, the individual may be immunocompromised, making them vulnerable to pathogens. The information presented here has been extensively reviewed, compiled, and analyzed from authenticated published resources available on Medline, PubMed, PubMed Central, Science Direct, and other scientific databases. Stress levels can be monitored by the quantitative and qualitative measurement of biomarkers. Potential markers of stress include thermal stress markers, such as heat shock proteins (HSPs), innate immune markers, such as Acute Phase Proteins (APPs), oxidative stress markers, and chemical secretions in the saliva and urine. In addition, stress biomarkers also play critical roles in the prognosis of stress-related diseases and disorders, and therapy guidance. Moreover, different components have been identified as potent mediators of cardiovascular, central nervous system, hepatic, and nephrological disorders, which can also be employed to evaluate these conditions precisely, but with stringent validation and specificity. Considerable scientific advances have been made in the detection, quantitation, and application of these biomarkers. The present review describes the current progress of identifying biomarkers, their prognostic, and therapeutic values.

Association of Acute Increases in Plasma Creatinine after Renin-Angiotensin Blockade with Subsequent Outcomes

BACKGROUND AND OBJECTIVES

Data from observational and interventional studies provide discordant results regarding the relationship between creatinine increase after renin-angiotensin system inhibition (RASi) and adverse outcomes. We compared health outcomes among patients with different categories of increase in creatinine upon initiation of RASi in a large population-based cohort.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We performed a retrospective analysis of the Stockholm CREAtinine Measurements database, which contains complete information on diagnoses, medication dispensation claims, and laboratory test results for all Stockholm citizens accessing health care. Included were 31,951 adults initiating RASi during 2007-2011 with available pre- and postinitiation creatinine monitoring. Multivariable Cox regression was used to compare mortality, cardiovascular and ESKD events among individuals with different ranges of creatinine increases within 2 months after starting treatment.

RESULTS

In a median follow-up of 3.5 years, acute increases in creatinine were associated with mortality (3202 events) in a graded manner: compared with creatinine increases <10%, a 10%-19% increase showed an adjusted hazard ratio (HR) of 1.15 (95% confidence interval [95% CI], 1.05 to 1.27); HR 1.22 (95% CI, 1.07 to 1.40) for 20%-29%; HR 1.55 (95% CI, 1.36 to 1.77) for ≥30%. Similar graded associations were present for heart failure (2275 events, P<0.001) and ESKD (52 events; P<0.001), and, less consistently, myocardial infarction (842 events, P=0.25). Results were robust across subgroups, among continuing users, when patients with decreases in creatinine were excluded from the reference group, and after accounting for death as a competing risk.

CONCLUSIONS

Among real-world monitored adults, increases in creatinine (>10%) after initiation of RASi are associated with worse health outcomes. These results do not address the issue of discontinuation of RASi when plasma creatinine increases but do suggest that patients with increases in creatinine have higher subsequent risk of cardiovascular and kidney outcomes.

New Insights Into Mechanisms of Acute Kidney Injury in Heart Disease

Acute kidney injury is a frequent occurrence in patients with heart disease, and is associated with higher risk of adverse outcomes, including mortality. In the setting of decompensated heart failure, acute kidney injury can occur from hemodynamic and neurohormonal activation, venous congestion, and nephrotoxic medications. Certain medications, such as loop diuretics, renin angiotensin system blockers, and mineralocorticoid antagonists can seemingly cause acute kidney injury. However, this increase in creatinine level is not always associated with adverse outcomes and should be carefully differentiated so as to allow deliberate continuation of these cardio- and nephroprotective agents. In other settings such as cardiac surgery, acute kidney injury can occur from factors related to the cardiopulmonary bypass, renal hypoperfusion, or other perioperative factors. Last, patients with heart disease commonly undergo imaging procedures that require contrast administration. Contrast can indeed cause acute kidney injury, but these interventional procedures also can result in kidney injury from atheroembolic phenomena. This is well documented by the recent data reporting a higher risk of acute kidney injury from femoral compared with radial access. The advent of biomarkers of kidney injury present an opportunity for early detection, accurate differential diagnosis, as well as potentially designing innovative biomarker-enriched adaptive clinical trials.

Effects of Intensive Blood Pressure Lowering on Kidney Tubule Injury in CKD: A Longitudinal Subgroup Analysis in SPRINT

BACKGROUND

Random assignment to the intensive systolic blood pressure (SBP) arm (<120mmHg) in the Systolic Blood Pressure Intervention Trial (SPRINT) resulted in more rapid declines in estimated glomerular filtration rates (eGFRs) than in the standard arm (SBP<140mmHg). Whether this change reflects hemodynamic effects or accelerated intrinsic kidney damage is unknown.

STUDY DESIGN

Longitudinal subgroup analysis of clinical trial participants.

SETTINGS & PARTICIPANTS

Random sample of SPRINT participants with prevalent chronic kidney disease (CKD) defined as eGFR<60mL/min/1.73m² by the CKD-EPI (CKD Epidemiology Collaboration) creatinine-cystatin C equation at baseline.

OUTCOMES & MEASUREMENTS

Urine biomarkers of tubule function (β₂-microglobulin [B2M], α₁-microglobulin [A1M]), and uromodulin), injury (interleukin 18, kidney injury molecule 1, and neutrophil gelatinase-associated lipocalin), inflammation (monocyte chemoattractant protein 1), and repair (human cartilage glycoprotein 40) at baseline, year 1, and year 4. Biomarkers were indexed to urine creatinine concentration and changes between arms were evaluated using mixed-effects linear models and an intention-to-treat approach.

RESULTS

978 SPRINT participants (519 in the intensive and 459 in the standard arm) with prevalent CKD were included. Mean age was 72±9 years and eGFR was 46.1±9.4mL/min/1.73m² at baseline. Clinical characteristics, eGFR, urinary albumin-creatinine ratio, and all 8 biomarker values were similar across arms at baseline. Compared to the standard arm, eGFR was lower by 2.9 and 3.3mL/min/1.73m² in the intensive arm at year 1 and year 4. None of the 8 tubule marker levels was higher in the intensive arm compared to the standard arm at year 1 or year 4. Two tubule function markers (B2M and A1M) were 29% (95% CI, 10%-43%) and 24% (95% CI, 10%-36%) lower at year 1 in the intensive versus standard arm, respectively.

LIMITATIONS

Exclusion of persons with diabetes, and few participants had advanced CKD.

CONCLUSIONS

Among participants with CKD in SPRINT, random assignment to the intensive SBP arm did not increase any levels of 8 urine biomarkers of tubule cell damage despite loss of eGFR. These findings support the hypothesis that eGFR declines in the intensive arm of SPRINT predominantly reflect hemodynamic changes rather than intrinsic damage to kidney tubule cells.