Mortality and morbidity in relation to changes in albuminuria, glucose status and systolic blood pressure: an analysis of the ONTARGET and TRANSCEND studies

Diabetic Nephropathy: Update on Pillars of Therapy Slowing Progression

Management of diabetic kidney disease (DKD) has evolved in parallel with our growing understanding of the multiple interrelated pathophysiological mechanisms that involve hemodynamic, metabolic, and inflammatory pathways. These pathways and others play a vital role in the initiation and progression of DKD. Since its initial discovery, the blockade of the renin-angiotensin system has remained a cornerstone of DKD management, leaving a large component of residual risk to be dealt with. The advent of sodium-glucose cotransporter 2 inhibitors followed by nonsteroidal mineralocorticoid receptor antagonists and, to some extent, glucagon-like peptide 1 receptor agonists (GLP-1 RAs) has ushered in a resounding paradigm shift that supports a pillared approach in maximizing treatment to reduce outcomes. This pillared approach is like that derived from the approach to heart failure treatment. The approach mandates that all agents that have been shown in clinical trials to reduce cardiovascular outcomes and/or mortality to a greater extent than a single drug class alone should be used in combination. In this way, each drug class focuses on a specific aspect of the disease's pathophysiology. Thus, in heart failure, β-blockers, sacubitril/valsartan, a mineralocorticoid receptor antagonist, and a diuretic are used together. In this article, we review the evolution of the pillar concept of therapy as it applies to DKD and discuss how it should be used based on the outcome evidence. We also discuss the exciting possibility that GLP-1 RAs may be an additional pillar in the quest to further slow kidney disease progression in diabetes.

Leveraging the South African Diabetes Prevention Programme to screen for chronic kidney disease: an observational study

OBJECTIVE

To evaluate the viability of leveraging an existing screening programme (the South African Diabetes Prevention Programme (SA-DPP)) to screen for chronic kidney disease (CKD), by assessing the yield of CKD cases among those participating in the programme.

DESIGN

Observational study conducted between 2017 and 2019.

SETTING

16 resource-poor communities in Cape Town, South Africa.

PARTICIPANTS

690 participants, aged between 25 and 65 years, identified as at high risk for type 2 diabetes mellitus (T2DM) by the African Diabetes Risk Score.

PRIMARY OUTCOME MEASURE

The prevalence of CKD among those participating in the SA-DPP.

RESULTS

Of the 2173 individuals screened in the community, 690 participants underwent further testing. Of these participants, 9.6% (n=66) and 18.1% (n=125) had screen-detected T2DM and CKD (defined as an estimated glomerular filtration rate (eGFR) of<60 mL/min/1.73 m² and/or albumin-to-creatinine ratio >3 mg/mmol), respectively. Of those with CKD, 73.6% (n=92), 17.6% (n=22) and 8.8% (n=11) presented with stages 1, 2 and 3, respectively. Of the participants with an eGFR <60 mL/min/1.73 m², 36.4% had no albuminuria and of those with normal kidney function (eGFR ≥90 mL/min/1.73 m²), 10.2% and 3.8% had albuminuria stages 2 and 3, respectively. Of those with T2DM and hypertension, 22.7% and 19.8% had CKD, respectively.

CONCLUSION

The fact that almost one in five participants identified as high risk for T2DM had CKD underscores the value of including markers of kidney function in an existing screening programme. By using an opportunistic approach to screen high-risk individuals, those with CKD can be identified and appropriately treated to reduce disease progression.

Efficacy and Safety of Finerenone in Chronic Kidney Disease: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Background: Chronic kidney disease (CKD) is a global public health issue. In recent years, the effectiveness of finerenone for treatment of CKD has been the subject of considerable debate. The main objective of the current meta-analysis was to validate the clinical efficacy and safety of finerenone in patients with CKD.

Methods: Seven databases were searched for randomized controlled trials (RCTs) comparing finerenone with placebo in patients with CKD. Data from eligible studies were extracted, and the Cochrane risk of bias tool utilized for evaluating the methodological quality of RCTs. The effect size was estimated using the risk ratio (RR) and mean difference (MD) with 95% confidence interval (CI).

Results: Five trials (n = 13,078) were included. Compared to placebo groups, the urinary albumin-to-creatinine ratio (UACR) mean from the baseline was significantly lower [MD −0.30 (95% CI −0.32, −0.28), p < 0.00001], while a decrease in the estimated glomerular filtration rate (eGFR) from baseline was significantly higher [MD −2.44 (95% CI −2.82, −2.05), p < 0.00001] for the finerenone groups. Furthermore, the proportion of patients with decreased eGFR (≥40%) post-baseline was significantly lower [RR 0.85 (95% CI 0.78, 0.93), p = 0.0002], along with end-stage kidney disease (ESKD) [RR 0.80 (95% CI 0.65, 0.99), p = 0.04] and cardiovascular events (CVs) [RR 0.88 (95% CI 0.80, 0.95), p < 0.003] in the finerenone groups. In terms of safety, the increase in the serum potassium concentration and incidence of hyperkalemia was significantly higher for the finerenone groups [MD 0.17 (95% CI 0.10, 0.24), p < 0.00001; RR 2.03 (95% CI 1.83, 2.26), p < 0.00001, respectively], but the incidence of adverse events (AEs) was similar to placebo [RR 1.00 (95% CI 0.98–1.01), p = 0.67]. In all cases, the results were rated as providing moderate-quality or high-quality evidence.

Conclusion: Data from our meta-analysis suggest that finerenone confers significant renal and cardiovascular benefits in patients with CKD. While higher risk of hyperkalemia was observed with finerenone than placebo, differences in AEs were not significant. Finerenone may therefore present a novel promising therapeutic agent for patients with CKD.

Systematic Review Registration: [https://inplasy.com/inplasy-2021-9-0020/], identifier [INPLASY202190020].

Change in Urine Albumin-to-Creatinine Ratio and Risk of Diabetic Peripheral Neuropathy in Type 2 Diabetes: A Retrospective Cohort Study

PURPOSE

This study aimed to assess association between change in urine albumin-to-creatinine ratio (UACR) and the risk of diabetic peripheral neuropathy (DPN) in type 2 diabetes mellitus.

PATIENTS AND METHODS

A retrospective study was performed, which included 185 individuals with type 2 diabetes. At baseline, and at two-year follow-up, we collected basic data, recorded symptoms and signs of DPN, measured biochemical indicators, composite motor nerve conduction velocity (composite MCV), and composite sensory nerve conduction velocity (composite SCV).

RESULTS

Changes of composite SCV, MCV and TCSS among different changes in UACR in patients without DPN and with DPN were not significantly different. An increase in UACR ≥30% (OR 3.059, 95%; CI: 1.012-9.249) suggested a risk for new-onset DPN. Based on ROC curve analysis, the areas under the curve were 0.654 ± 0.066 for change of UACR levels in non-DPN patients.

CONCLUSION

Change in UACR and NCV was not related in patients without DPN and with DPN; change in UACR ≥30% suggested a risk for new-onset DPN.

Visit-to-visit blood pressure variability and renal outcomes: results from ONTARGET and TRANSCEND trials

AIMS

There is conflicting evidence on whether in treated hypertensive patients the risk of renal outcomes is associated with visit-to-visit SBP variability. Furthermore, limited evidence is available on how important is SBP variability for prediction of renal outcomes compared with on-treatment mean SBP. We addressed these issues in 28 790 participants of the Ongoing Treatment Alone and in combination with Ramipril Global End point Trial and Telmisartan Randomized AssessmeNt Study in ACE iNtolerant Subjects with Cardiovascular Disease trials.

METHODS AND RESULTS

SBP variability was expressed as the coefficient of variation of the mean with which it showed no relationship. SBP variability and mean values were obtained from five visits during the first 2 years of treatment after the end of the titration phase. Incidence of several renal outcomes (end-stage renal disease, doubling of serum creatinine, new microalbuminuria, new macroalbuminuria and their composite) was calculated from the third year of treatment onward. Patients were divided in quintiles of SBP-coefficient of variation (SBP-CV) or mean SBP, which exhibited superimposable mean blood pressure and SBP-CV values, respectively. A progressive increase of SBP-CV was not accompanied by a parallel increase in a widely adjusted (baseline and on-treatment confounders) risk of most renal outcomes (end-stage renal disease, new macroalbuminuria, new microalbuminuria and their composite) in the subsequent on-treatment years. In contrast, the adjusted risk of most renal outcomes increased progressively from the lowest to the highest quintile of on-treatment mean SBP. Progression from lowest to highest mean on-treatment SBP, but not SBP-CV, was also associated with a less frequent return to normoalbuminuria in patients with initial micro or macroalbuminuria. Renal outcome prediction was slightly improved by the combined use of SBP-CV and mean SBP quintiles.

CONCLUSION

Visit-to-visit SBP variability had no major predictive value for the risk of renal outcomes, which, in contrast, was sensitively predicted by mean on-treatment SBP. A further slight increase in prediction of renal outcomes was seen by combining on-treatment mean SBP and variability.

Frequency of alcohol drinking modifies the association between salt intake and albuminuria: a 1-year observational study

Albuminuria is an important risk factor for end-stage kidney disease and cardiovascular mortality. This 1-year observational study aimed to assess the effect modification of alcohol drinking on the association between salt intake and albuminuria. Overall, 448 employees at a pharmaceutical company in Japan who underwent annual health checkups in both 2017 and 2018 were evaluated. The main exposure of interest was drinking frequency at their first checkups categorized as rarely, occasionally, and daily. To assess the association between the changes in salt intake and albuminuria, the differences in salt intake estimated from single-spot urine specimens and the urinary albumin-to-creatinine ratio (UACR) between 2017 and 2018 were calculated for each subject. A multivariable-adjusted linear regression model showed a significant association between ∆salt intake and ∆Log UACR (per 1 g/day of ∆salt intake, adjusted ß 0.16 [95% confidence interval 0.14, 0.19]) and an effect modification between drinking frequency and ∆salt intake (P for interaction = 0.088). The association between ∆salt intake and ∆Log UACR was enhanced by drinking frequency in a dose-dependent manner (per 1 g/day of ∆salt intake, adjusted ß 0.13 [0.06, 0.19], 0.16 [0.12, 0.20], and 0.20 [0.13, 0.27] in rare, occasional, and daily drinkers, respectively). In conclusion, the results of the present study indicated that salt-induced albuminuria was enhanced in subjects with higher drinking frequency, suggesting that salt restriction may have a stronger renoprotective effect in subjects with higher drinking frequency.

Effect of a Single Intravitreal Bevacizumab Injection on Proteinuria in Patients With Diabetes

Purpose

Proteinuria is the second most common complication after hypertension after systemic administration of bevacizumab. Therefore we aimed to analyze the effect of intravitreal bevacizumab (IVB) injection on proteinuria in patients with diabetes.

Methods

Patients scheduled to receive IVB injection from May 1, 2018, to December 31, 2018, were prospectively enrolled. In total, 53 patients with diabetes (26 with nonproliferative diabetic retinopathy and 27 with proliferative diabetic retinopathy) and 37 patients without diabetes were included. Urine tests were performed within 1 month of and 7 ± 1 days after IVB injection. Urinary protein, creatinine, and albumin concentrations were quantitatively measured, and urinary protein-to-creatinine ratio and urinary albumin-to-creatinine ratio (UACR) were calculated from these data before and after IVB injection.

Results

The mean urinary microalbumin concentrations and urinary protein-to-creatinine ratio were significantly higher in patients with diabetes, both before and after IVB injection. There were no differences between patients with nonproliferative diabetic retinopathy and proliferative diabetic retinopathy. About 80% of patients with diabetes showed improved albuminuria or at least no harmful effect in terms of albuminuria. Patients with deteriorated baseline UACR showed more residual increase in UACR after IVB injection (P < 0.05 in all groups).

Conclusions

Close monitoring of renal function after IVB might be needed in patients with diabetes according to the severity of nephropathy.

Translational Relevance

Our results may provide information regarding the renal function of IVB-treated patients with diabetes.

Microalbuminuria and cardiorenal risk: old and new evidence in different populations

Since the association of microalbuminuria (MAU) with cardiovascular (CV) risk was described, a huge number of reports have emerged. MAU is a specific integrated marker of CV risk and targets organ damage in patients with hypertension, chronic kidney disease (CKD), and diabetes and its recognition is important for identifying patients at a high or very high global CV risk. The gold standard for diagnosis is albumin measured in 24-hour urine collection (normal values of less than 30 mg/day, MAU of 30 to 300 mg/day, macroalbuminuria of more than 300 mg/day) or, more practically, the determination of urinary albumin-to-creatinine ratio in a urine morning sample (30 to 300 mg/g). MAU screening is mandatory in individuals at risk of developing or presenting elevated global CV risk. Evidence has shown that intensive treatment could turn MAU into normoalbuminuria. Intensive treatment with the administration of an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker, in combination with other anti-hypertensive drugs and drugs covering other aspects of CV risk, such as mineralocorticoid receptor antagonists, new anti-diabetic drugs, and statins, can diminish the risk accompanying albuminuria in hypertensive patients with or without CKD and diabetes.

Predicting albuminuria response to spironolactone treatment with urinary proteomics in patients with type 2 diabetes and hypertension

Background

The mineralocorticoid receptor antagonist spironolactone significantly reduces albuminuria in patients with diabetes. Prior studies have shown large between-patient variability in albuminuria treatment response. We previously developed and validated a urinary proteomic classifier that predicts onset and progression of chronic kidney disease. Here, we tested whether the proteomic classifier based on 273 urinary peptides (CKD273) predicts albuminuria response to spironolactone treatment.

Methods

We performed a post hoc analysis in a double-blind randomized clinical trial with allocation to either spironolactone 12.5-50 mg/day (n = 57) or placebo (n = 54) for 16 weeks. Patients were diagnosed with type 2 diabetes and resistant hypertension. Treatment was an adjunct to renin-angiotensin system inhibition. Primary endpoint was the percentage change in urine albumin to creatinine ratio (UACR). Capillary electrophoresis mass spectrometry was used to quantify urinary peptides at baseline. The previously validated combination of 273 known urinary peptides was used as proteomic classifier.

Results

Spironolactone reduced UACR relative to placebo by 50%, although with a large between-patient variability in UACR response (5th to 95th percentile, 7 to 312%). An interaction was detected between CKD273 and treatment assignment (β = -1.09, P = 0.026). Higher values of CKD273 at baseline were associated with a larger reduction in UACR in the spironolactone group (β = -0.70, P = 0.049), but not in the placebo group (β = 0.39, P = 0.25). Stratified in tertiles of baseline CKD273, reduction in UACR was greater in the highest tertile, 63% (95% confidence interval: 35-79%), as compared with the two other tertiles combined, 16% (-17 to 40%) (P = 0.011).

Conclusions

A urinary proteomics classifier can be used to identify individuals with type 2 diabetes who are more likely to show an albuminuria-lowering response to spironolactone treatment. These results suggest that urinary proteomics may be a valuable tool to tailor therapy, but confirmation in a larger clinical trial is required.

Abelmoschus manihot for Diabetic Nephropathy: A Systematic Review and Meta-Analysis

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease (ESRD). Many trials have shown that Abelmoschus manihot could further improve proteinuria and protect kidney function in patients with DN when added to a renin-angiotensin system (RAS) blocker. A systematic assessment of the efficacy and safety of A. manihot in DN is essential. Eight electronic databases were searched to identify eligible trials published from inception to December 2017. The Cochrane Risk of Bias Tool was used to evaluate the methodological quality of eligible studies. Seventy-two studies with 5,895 participants were identified. The methodological quality of included studies was generally low. The results indicated that, compared to a RAS blocker, combined treatment of A. manihot with a RAS blocker was more effective for 24h urinary protein (24h UP) (mean difference [MD], -0.39 [95% confidence interval [CI], -0.46 to -0.33] g/d; P<0.00001), urinary albumin excretion rate (UAER)(MD, -19.90 [95% CI, -22.62 to -17.18] μg/min; P<0.00001), 24h UP reduction rate (risk ratio [RR], 1.43; 95% CI, 1.26-1.63; P<0.00001), normalization of UAER (RR, 1.48; 95% CI, 1.29-1.70; P<0.00001), and serum creatinine (SCr) (MD, -7.35 [95% CI, -9.95 to -4.76] umol/L; P<0.00001). None of these trials reported the ESRD rate. No statistically significant difference occurred between A. manihot combined with a RAS blocker and a RAS blocker alone in estimated glomerular filtration rate (eGFR) (MD, 4.43 [95% CI, -1.68 to 10.54] mL/min; P=0.16). A. manihot did not increase the rates of adverse drug events. A. manihot in addition to a RAS blocker was effective and safe to further improve proteinuria and protect kidney function in patients with DN. However, due to the generally low methodological quality, significant heterogeneity, and publication bias, high-quality randomized controlled trials are required to confirm these findings before the routine use of A. manihot can be recommended.

Blood pressure targets in type 2 diabetes. Evidence against or in favour of an aggressive approach

When associated with high blood pressure, type 2 diabetes mellitus is characterised by a high risk of adverse cardiovascular (CV) and renal outcomes. However, both can be effectively reduced by antihypertensive treatment. Current guidelines on the treatment of hypertension emphasize the need to effectively treat high blood pressure in diabetic individuals, but their recommendations differ in terms of the optimal target blood pressure value to aim for in order to maximise CV and renal protection. In some guidelines the recommended target blood pressure values are <140/90 mmHg (systolic/diastolic), whereas in others, blood pressure values close or even less than 130/80 mmHg are recommended. This paper will discuss the evidence for and against a conservative or more aggressive blood pressure target for treated diabetic hypertensive individuals based on the evidence provided by randomised trials, trial meta-analyses and large observational studies. Based on the available evidence, it appears that blood pressure targets will probably have to be lower than <140/90 mmHg, and that values approaching 130/80 mmHg should be recommended. However, evidence in favour of even lower systolic values, i.e. <130 mmHg, is limited and is definitively against a reduction to <120 mmHg.

Changes in Albuminuria and Subsequent Risk of Incident Kidney Disease

BACKGROUND AND OBJECTIVES

Albuminuria is a robust predictor of CKD progression. However, little is known about the associations of changes in albuminuria with the risk of kidney events outside the settings of clinical trials.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In a nationwide cohort of 56,946 United States veterans with an eGFR≥60 ml/min per 1.73 m2, we examined the associations of 1-year fold changes in albuminuria with subsequent incident CKD (>25% decrease in eGFR reaching <60 ml/min per 1.73 m2) and rapid eGFR decline (eGFR slope <-5 ml/min per 1.73 m2 per year) assessed using Cox models and logistic regression, respectively, with adjustment for confounders.

RESULTS

The mean age was 64 (SD, 10) years old; 97% were men, and 91% were diabetic. There was a nearly linear association between 1-year fold changes in albuminuria and incident CKD. The multivariable-adjusted hazard ratios (95% confidence intervals) of incident CKD associated with more than twofold decrease, 1.25- to twofold decrease, 1.25- to twofold increase, and more than twofold increase (versus <1.25-fold decrease to <1.25-fold increase) in albuminuria were 0.82 (95% confidence interval, 0.77 to 0.89), 0.93 (95% confidence interval, 0.86 to 1.00), 1.12 (95% confidence interval, 1.05 to 1.20), and 1.29 (95% confidence interval, 1.21 to 1.38), respectively. Qualitatively similar associations were present for rapid eGFR decline (adjusted odds ratios; 95% confidence intervals for corresponding albuminuria changes: adjusted odds ratio, 0.86; 95% confidence interval, 0.78 to 0.94; adjusted odds ratio, 0.98; 95% confidence interval, 0.89 to 1.07; adjusted odds ratio, 1.18; 95% confidence interval, 1.08 to 1.29; and adjusted odds ratio, 1.67; 95% confidence interval, 1.54 and 1.81, respectively).

CONCLUSIONS

Relative changes in albuminuria over a 1-year interval were linearly associated with subsequent risk of kidney outcomes. Additional studies are warranted to elucidate the underlying mechanisms of the observed associations and test whether active interventions to lower elevated albuminuria can improve kidney outcomes.

Protective effect of rosiglitazone on kidney function in high-fat challenged human-CRP transgenic mice: a possible role for adiponectin and miR-21?

Obesity-related albuminuria is associated with decline of kidney function and is considered a first sign of diabetic nephropathy. Suggested factors linking obesity to kidney dysfunction include low-grade inflammation, insulin resistance and adipokine dysregulation. Here, we investigated the effects of two pharmacological compounds with established anti-inflammatory properties, rosiglitazone and rosuvastatin, on kidney dysfunction during high-fat diet (HFD)-induced obesity. For this, human CRP transgenic mice were fed standard chow, a lard-based HFD, HFD+rosuvastatin or HFD+rosiglitazone for 42 weeks to study effects on insulin resistance; plasma inflammatory markers and adipokines; and renal pathology. Rosiglitazone but not rosuvastatin prevented HFD-induced albuminuria and renal fibrosis and inflammation. Also, rosiglitazone prevented HFD-induced KIM-1 expression, while levels were doubled with rosuvastatin. This was mirrored by miR-21 expression, which plays a role in fibrosis and is associated with renal dysfunction. Plasma insulin did not correlate with albuminuria. Only rosiglitazone increased circulating adiponectin concentrations. In all, HFD-induced albuminuria, and renal inflammation, injury and fibrosis is prevented by rosiglitazone but not by rosuvastatin. These beneficial effects of rosiglitazone are linked to lowered miR-21 expression but not connected with the selectively enhanced plasma adiponectin levels observed in rosiglitazone-treated animals.

Intravital imaging of the kidney in a rat model of salt-sensitive hypertension

Hypertension is one of the most prevalent diseases worldwide and a major risk factor for renal failure and cardiovascular disease. The role of albuminuria, a common feature of hypertension and robust predictor of cardiorenal disorders, remains incompletely understood. The goal of this study was to investigate the mechanisms leading to albuminuria in the kidney of a rat model of hypertension, the Dahl salt-sensitive (SS) rat. To determine the relative contributions of the glomerulus and proximal tubule (PT) to albuminuria, we applied intravital two-photon-based imaging to investigate the complex renal physiological changes that occur during salt-induced hypertension. Following a high-salt diet, SS rats exhibited elevated blood pressure, increased glomerular sieving of albumin (GSC_alb = 0.0686), relative permeability to albumin (+Δ16%), and impaired volume hemodynamics (-Δ14%). Serum albumin but not serum globulins or creatinine concentration was decreased (-0.54 g/dl), which was concomitant with increased filtration of albumin (3.7 vs. 0.8 g/day normal diet). Pathologically, hypertensive animals had significant tubular damage, as indicated by increased prevalence of granular casts, expansion and necrosis of PT epithelial cells (+Δ2.20 score/image), progressive augmentation of red blood cell velocity (+Δ269 µm/s) and micro vessel diameter (+Δ4.3 µm), and increased vascular injury (+Δ0.61 leakage/image). Therefore, development of salt-induced hypertension can be triggered by fast and progressive pathogenic remodeling of PT epithelia, which can be associated with changes in albumin handling. Collectively, these results indicate that both the glomerulus and the PT contribute to albuminuria, and dual treatment of glomerular filtration and albumin reabsorption may represent an effective treatment of salt-sensitive hypertension.

Effect of Saxagliptin on Renal Outcomes in the SAVOR-TIMI 53 Trial

OBJECTIVE

Dipeptidyl peptidase 4 inhibitors may have a protective effect in diabetic nephropathy.

RESEARCH DESIGN AND METHODS

We studied renal outcomes of 16,492 patients with type 2 diabetes, randomized to saxagliptin versus placebo and followed for a median of 2.1 years in the Saxagliptin Assessment of Vascular Outcomes Recorded in Patients with Diabetes Mellitus-Thrombolysis in Myocardial Infarction 53 (SAVOR-TIMI 53) trial.

RESULTS

At baseline, 9,696 (58.8%) subjects had normoalbuminuria (albumin/creatinine ratio [ACR] <30 mg/g), 4,426 (26.8%) had microalbuminuria (ACR 30-300 mg/g), and 1,638 (9.9%) had macroalbuminuria (ACR >300 mg/g). Treatment with saxagliptin was associated with improvement in and/or less deterioration in ACR categories from baseline to end of trial (EOT) (P = 0.021, P < 0.001, and P = 0.049 for individuals with baseline normoalbuminuria, microalbuminuria, and macroalbuminuria, respectively). At 2 years, the difference in mean ACR change between saxagliptin and placebo arms was -19.3 mg/g (P = 0.033) for estimated glomerular filtration rate (eGFR) >50 mL/min/body surface area per 1.73 m² (BSA), -105 mg/g (P = 0.011) for 50 ≥ eGFR ≥ 30 mL/min/BSA, and -245.2 mg/g (P = 0.086) for eGFR <30 mL/min/BSA. Analyzing ACR as a continuous variable showed reduction in ACR with saxagliptin (1 year, P < 0.0001; 2 years, P = 0.0143; and EOT, P = 0.0158). The change in ACR did not correlate with that in HbA_1c (r = 0.041, 0.052, and 0.036; 1 year, 2 years, and EOT, respectively). The change in eGFR was similar in the saxagliptin and placebo groups. Safety renal outcomes, including doubling of serum creatinine, initiation of chronic dialysis, renal transplantation, or serum creatinine >6.0 mg/dL, were similar as well.

CONCLUSIONS

Treatment with saxagliptin improved ACR, even in the normoalbuminuric range, without affecting eGFR. The beneficial effect of saxagliptin on albuminuria could not be explained by its effect on glycemic control.

Specific Blood Pressure Targets for Patients With Diabetic Nephropathy?

Diabetic nephropathy represents a condition frequently detected in current clinical practice characterized by a very high cardiovascular risk profile. Blood pressure reduction via antihypertension drug treatment represents a therapeutic approach capable of exerting favorable effects on renal and cardiovascular outcomes. The purpose of this article is to review the current literature and results of key clinical trials pertaining to blood pressure goals of antihypertension treatment in these patients. The pros and cons of a less or a more intensive blood pressure goal in diabetic nephropathy will be discussed, with particular emphasis on the cardiovascular and renal effects of each therapeutic strategy.

The use of green tea polyphenols for treating residual albuminuria in diabetic nephropathy: A double-blind randomised clinical trial

Prior research has shown that in experimental diabetes mellitus, green tea reduces albuminuria by decreasing podocyte apoptosis through activation of the WNT pathway. We investigated the effect of green tea polyphenols (GTP) on residual albuminuria of diabetic subjects with nephropathy. We conducted a randomised, double-blind study in 42 diabetic subjects with a urinary albumin-creatinine ratio (UACR) >30 mg/g, despite administration of the maximum recommended dose of renin-angiotensin (RAS) inhibition. Patients were randomly assigned to two equal groups to receive either GTP (containing 800 mg of epigallocatechin gallate, 17 with type 2 diabetes and 4 with type 1 diabetes) or placebo (21 with type 2 diabetes) for 12 weeks. Treatment with GTP reduced UACR by 41%, while the placebo group saw a 2% increase in UACR (p = 0.019). Podocyte apoptosis (p = 0.001) and in vitro albumin permeability (p < 0.001) were higher in immortalized human podocytes exposed to plasma from diabetic subjects compared to podocytes treated with plasma from normal individuals. In conclusion, GTP administration reduces albuminuria in diabetic patients receiving the maximum recommended dose of RAS. Reduction in podocyte apoptosis by activation of the WNT pathway may have contributed to this effect.

Additive Effect of Qidan Dihuang Grain, a Traditional Chinese Medicine, and Angiotensin Receptor Blockers on Albuminuria Levels in Patients with Diabetic Nephropathy: A Randomized, Parallel-Controlled Trial

Albuminuria is characteristic of early-stage diabetic nephropathy (DN). The conventional treatments with angiotensin receptor blockers (ARB) are unable to prevent the development of albuminuria in normotensive individuals with type 2 diabetes mellitus (T2DM). Purpose. The present study aimed to evaluate the effect of ARB combined with a Chinese formula Qidan Dihuang grain (QDDHG) in improving albuminuria and Traditional Chinese Medicine Symptom (TCMS) scores in normotensive individuals with T2DM. Methods. Eligible patients were randomized to the treatment group and the control group. Results. Compared with baseline (week 0), both treatment and control groups markedly improved the 24-hour albuminuria, total proteinuria (TPU), and urinary albumin to creatinine ratio (A/C) at 4, 8, and 12 weeks. Between treatment and the control group, the levels of albuminuria in the treatment group were significantly lower than in the control group at 8 and 12 weeks (p < 0.05). In addition, treatment group markedly decreased the scores of TCMS after treatment. Conclusion. This trial suggests that QDDHG combined with ARB administration decreases the levels of albuminuria and the scores for TCMS in normotensive individuals with T2DM.

Proteomic prediction and Renin angiotensin aldosterone system Inhibition prevention Of early diabetic nephRopathy in TYpe 2 diabetic patients with normoalbuminuria (PRIORITY): essential study design and rationale of a randomised clinical multicentre trial

INTRODUCTION

Diabetes mellitus affects 9% of the European population and accounts for 15% of healthcare expenditure, in particular, due to excess costs related to complications. Clinical trials aiming for earlier prevention of diabetic nephropathy by renin angiotensin system blocking treatment in normoalbumuric patients have given mixed results. This might reflect that the large fraction of normoalbuminuric patients are not at risk of progression, thereby reducing power in previous studies. A specific risk classifier based on urinary proteomics (chronic kidney disease (CKD)273) has been shown to identify normoalbuminuric diabetic patients who later progressed to overt kidney disease, and may hold the potential for selection of high-risk patients for early intervention. Combining the ability of CKD273 to identify patients at highest risk of progression with prescription of preventive aldosterone blockade only to this high-risk population will increase power. We aim to confirm performance of CKD273 in a prospective multicentre clinical trial and test the ability of spironolactone to delay progression of early diabetic nephropathy.

METHODS AND ANALYSIS

Investigator-initiated, prospective multicentre clinical trial, with randomised double-masked placebo-controlled intervention and a prospective observational study. We aim to include 3280 type 2 diabetic participants with normoalbuminuria. The CKD273 classifier will be assessed in all participants. Participants with high-risk pattern are randomised to treatment with spironolactone 25 mg once daily, or placebo, whereas, those with low-risk pattern will be observed without intervention other than standard of care. Treatment or observational period is 3 years.The primary endpoint is development of confirmed microalbuminuria in 2 of 3 first morning voids urine samples.

ETHICS AND DISSEMINATION

The study will be conducted under International Conference on Harmonisation - Good clinical practice (ICH-GCP) requirements, ethical principles of Declaration of Helsinki and national laws. This first new biomarker-directed intervention trial aiming at primary prevention of diabetic nephropathy may pave the way for personalised medicine approaches in treatment of diabetes complications.

TRIAL REGISTRATION NUMBER

NCT02040441; Pre-results.

Effect of Sensor-Augmented Pump Treatment Versus Multiple Daily Injections on Albuminuria: A 1-Year Randomized Study

CONTEXT

The effect of glycemic control on persisting albuminuria remains unclear. Insulin delivery and glucose variability may be important.

OBJECTIVE

This study aimed to investigate the effect of 1-year treatment with sensor-augmented insulin pump (SAP) or multiple daily injections (MDIs) on albuminuria.

DESIGN, PATIENTS, AND METHODS

This was a randomized controlled open-label parallel trial composed of 60 patients with type 1 diabetes with a history of albuminuria and on stable renin-angiotensin system inhibition, were randomly assigned to SAP or MDI. Urine albumin creatinine ratio (UACR) was measured in three urine samples at all visits. Glucose variability and glomerular filtration rate ((51)Cr-EDTA-GFR) were measured at beginning and study end. Using linear mixed model, change in UACR between groups was analyzed as intention to treat.

MAIN OUTCOME MEASURE

Change in UACR was measured.

RESULTS

Fifty-five patients (SAP, n = 26; MDI, n = 29) completed the study. Diabetes duration (mean ± SD, 33 ± 12 y), UACR (geometric mean, 99 mg/g; interquartile range, 37-233 mg/g), (51)Cr-EDTA-GFR (94 ± 22 mL/min/1.73m(2)), glycosylated hemoglobin (HbA1c) (9.0 ± 1.1%), glucose variability (calculated as SD), 4.0 ± 1.0 mmol/l; no-group differences (P ≥ .06 for all). After 1 year, change in UACR was mean, -13%; 95% confidence interval, -39 to 22 with SAP vs mean, 30%; 95% CI, -12 to 92% on MDI treatment (unadjusted P = .051; adjusted for HbA1c, P = .04). HbA1c decreased 1.3 ± 1.0 vs 0.6 ± 1.0% (P = .013), glucose variability decreased 0.9 ± 1.1 vs 0.3 ± 1.0 mmol/L (P = .04), and (51)Cr-EDTA-GFR declined 5.6 ± 9.6 vs 3.4 ± 13 mL/min/1.73m(2) (P = .50) with SAP vs MDI treatment. There were no changes in blood pressure (P ≥ .27).

CONCLUSION

SAP treatment reduced UACR in a randomized controlled trial in type 1 diabetes patients with a history of albuminuria on stable renin-angiotensin system inhibition. Significance was reached after adjustment. SAP treatment reduced HbA1c and glucose variability (calculated as SD).

Effect of 4 years subcutaneous insulin infusion treatment on albuminuria, kidney function and HbA1c compared with multiple daily injections: a longitudinal follow-up study

AIM

The effect of insulin pump [continuous subcutaneous insulin infusion (CSII)] treatment on diabetes complications in a modern clinical setting is largely unknown. We investigated the effect of 4 years CSII treatment on HbA(1c), albuminuria and kidney function compared with multiple daily injections (MDI) in a single-centre clinical setting.

METHODS

All patients initiating CSII treatment from 2004 to 2010 and followed for at least 4 years were included in the study: 193 people with Type 1 diabetes were matched (1 : 2) with 386 patients treated with MDI in the same period. Matching was based on diabetes duration, gender, HbA(1c) and normo-, micro- or macroalbuminuria at baseline. Urinary albumin/creatinine ratio (UACR) was measured yearly and annual change assessed from linear regression.

RESULTS

CSII- vs. MDI-treated patients were comparable at baseline. After 4 years, HbA(1c) was 62 ± 11 vs. 68 ± 11 mmol/mol (7.8 ± 1.0 vs. 8.4 ± 1.0%) (P < 0.001). Annual UACR change in CSII- vs. MDI-treated patients was [mean (95% confidence interval)] -10.1 (-13.3; -6.8) vs. -1.2 (-3.6; 0.9)% (P < 0.001). Reduction in UACR was significantly associated with CSII treatment after adjustment for age, gender, diabetes duration, estimated GFR, UACR, mean arterial pressure, HbA(1c), cholesterol, renin-angiotensin-aldosterone system inhibition, anti-hypertensive treatment and smoking (P < 0.001). This remained significant (P < 0.001) when only including patients on stable renin-angiotensin-aldosterone system inhibition during follow-up (n = 465).

CONCLUSIONS

Treatment with CSII over 4 years independently reduced HbA(1c) and UACR compared with MDI. Reduced UACR may be due to less glycaemic variability because the effect of CSII on HbA(1c) could only partially explain the effect. This needs confirmation in randomized controlled trials.

The glycocalyx--linking albuminuria with renal and cardiovascular disease

Albuminuria is commonly used as a marker of kidney disease progression, but some evidence suggests that albuminuria also contributes to disease progression by inducing renal injury in specific disease conditions. Studies have confirmed that in patients with cardiovascular risk factors, such as diabetes and hypertension, endothelial damage drives progression of kidney disease and cardiovascular disease. A key mechanism that contributes to this process is the loss of the glycocalyx--a polysaccharide gel that lines the luminal endothelial surface and that normally acts as a barrier against albumin filtration. Degradation of the glycocalyx in response to endothelial activation can lead to albuminuria and subsequent renal and vascular inflammation, thus providing a pathophysiological framework for the clinical association of albuminuria with renal and cardiovascular disease progression. In this Review, we examine the likely mechanisms by which glycocalyx dysfunction contributes to kidney injury and explains the link between cardiovascular disease and albuminuria. Evidence suggests that glycocalyx dysfunction is reversible, suggesting that these mechanisms could be considered as therapeutic targets to prevent the progression of renal and cardiovascular disease. This possibility enables the use of existing drugs in new ways, provides an opportunity to develop novel therapies, and indicates that albuminuria should be reconsidered as an end point in clinical trials.

Rationale, design, and baseline characteristics of ARTS-DN: a randomized study to assess the safety and efficacy of finerenone in patients with type 2 diabetes mellitus and a clinical diagnosis of diabetic nephropathy

BACKGROUND/AIMS

Finerenone decreases albuminuria in patients having heart failure with reduced ejection fraction and mild-to-moderate (stage 2-3) chronic kidney disease. The MinerAlocorticoid Receptor Antagonist Tolerability Study-Diabetic Nephropathy (ARTS-DN; NCT01874431) is a multicenter, randomized, double-blind, placebo-controlled, parallel-group, phase 2b study. ARTS-DN investigated whether the mineralocorticoid receptor antagonist finerenone reduces albuminuria without causing major alterations in serum potassium levels in patients with type 2 diabetes mellitus and a clinical diagnosis of DN who were receiving a renin-angiotensin-system (RAS) inhibitor.

METHODS

Patients were randomized to oral finerenone 1.25-20 mg or placebo once daily. The primary objectives were to assess the ratio of the urinary albumin-to-creatinine ratio at day 90 to that at baseline in patients receiving finerenone, and to compare it with that in the placebo group. Additional exploratory analyses included evaluating changes from baseline in serum potassium levels, efficacy and safety biomarkers, and health-related quality of life.

RESULTS

Of 1,501 patients screened, 821 (the sample population) received at least one dose of finerenone/placebo. Baseline characteristics included: male, 77.8%; white, 84.2%; very high albuminuria (formerly macroalbuminuria), 38.4%; high albuminuria (formerly microalbuminuria), 60.3%; median (range) estimated glomerular filtration rate, 66.3 (24.5-130.7) ml/min/1.73 m(2); and systolic blood pressure (mean ± standard deviation), 138.1 ± 14.4 mm Hg. There was a history of cardiovascular disease in 39.6%, diabetic neuropathy in 20.0%, and diabetic retinopathy in 19.9% of patients.

CONCLUSION

ARTS-DN is the first phase 2b trial of finerenone in combination with a RAS inhibitor in patients with type 2 diabetes mellitus and a clinical diagnosis of DN.

Microalbuminuria: a parameter that has changed diabetes care

Diabetic nephropathy is characterised by persistent albuminuria, elevated blood pressure, relentless decline in GFR and enhanced fatal and nonfatal cardiovascular diseases. Microalbuminuria has been central to the development of clinical practise in prevention and treatment of diabetic nephropathy and cardiovascular disease. Treatment-induced and spontaneous remission of microalbuminuria has been reported both in type 1 and type 2 diabetic patients, underlining the importance of sustained elevation of urinary albumin excretion. Recently many new biomarkers have been evaluated in diabetic patients, and apart from urinary proteomics, none has yet outperformed Harry Keen's discovery of microalbuminuria as the best screening tool for diabetic nephropathy. Remission of microalbuminuria preserves renal function. Microalbuminuria has also stood the test of time as a valid powerful independent predictor for fatal and nonfatal cardiovascular outcome in diabetes. Improved glycaemic control, blood pressure reduction, RAS blockade and multifactorial treatment of cardiovascular risk factors reduce the risk of development of micro-and macroalbuminuria, declining renal function and cardiovascular events.

Diabetic nephropathy in 2014: improved cardiorenal prognosis in diabetic nephropathy

In 2014, key studies in the field of diabetic nephropathy highlighted the importance of albuminuria as a predictor of cardiovascular risk and showed that the incidence of renal and cardiovascular complications is decreasing. Promising efficacy data were obtained with atrasentan, whereas a trial of bardoxolone methyl led to safety concerns.

Drug-Induced Reduction in Albuminuria Is Associated with Subsequent Renoprotection: A Meta-Analysis

Albuminuria has been proposed as a surrogate end point in randomized clinical trials of renal disease progression. Most evidence comes from observational analyses showing that treatment-induced short-term changes in albuminuria correlate with risk change for ESRD. However, such studies are prone to selection bias and residual confounding. To minimize this bias, we performed a meta-analysis of clinical trials to correlate the placebo-corrected drug effect on albuminuria and ESRD to more reliably delineate the association between changes in albuminuria and ESRD. MEDLINE and EMBASE were searched for clinical trials reported between 1950 and April 2014. Included trials had a mean follow-up of ≥1000 patient-years, reported ESRD outcomes, and measured albuminuria at baseline and during follow-up. Twenty-one clinical trials involving 78,342 patients and 4183 ESRD events were included. Median time to first albuminuria measurement was 6 months. Fourteen trials tested the effect of renin-angiotensin-aldosterone-system inhibitors and seven trials tested other interventions. We observed variability across trials in the treatment effect on albuminuria (range, -1.3% to -32.1%) and ESRD (range, -55% to +35% risk change). Meta-regression analysis revealed that the placebo-adjusted treatment effect on albuminuria significantly correlated with the treatment effect on ESRD: for each 30% reduction in albuminuria, the risk of ESRD decreased by 23.7% (95% confidence interval, 11.4% to 34.2%; P=0.001). The association was consistent regardless of drug class (P=0.73) or other patient or trial characteristics. These findings suggest albuminuria may be a valid substitute for ESRD in many circumstances, even taking into account possible other drug-specific effects that may alter renal outcomes.