Cardiovascular implications of proteinuria: an indicator of chronic kidney disease. Nat Rev Cardiol. 2009;6:301-311. [PMID: 19352334 DOI: 10.1038/nrcardio.2009.11]

Preoperative proteinuria is independently associated with mortality after fenestrated endovascular aneurysm repair

OBJECTIVE

Fenestrated endovascular aneurysm repair (FEVAR) has become a mainstay in treating complex aortic aneurysms, though baseline patient factors predicting long-term outcomes remain poorly understood. Proteinuria is an early marker for chronic kidney disease and associated with adverse cardiovascular outcomes, but its utility in patients with aortic aneurysms is unknown. We aimed to determine whether preoperative proteinuria impacts long-term survival after FEVAR.

METHODS

A single-institution, retrospective review of all elective FEVAR was performed. Preoperative proteinuria was assessed by urinalysis: negative (0-29 mg/dL), 1+ (30-100 mg/dL), 2+ (101-299 mg/dL), and 3+ (≥300 mg/dL). The cohort was stratified by patients with proteinuria (≥30 mg/dL) vs those without (<30 mg/dL). Baseline, perioperative, and long-term outcomes were compared. The primary outcome, all-cause mortality, was evaluated by Kaplan-Meier analysis and independent predictors with Cox proportional hazards modeling.

RESULTS

Among 181 patients who underwent standard FEVAR from 2012 to 2022 (mean follow-up 33 months), any proteinuria was noted in 30 patients (16.6%). Patients with proteinuria were more likely to be Black (10.0% vs 1.3%) with a lower estimated glomerular filtration rate (eGFR) (52.7 ± 24.7 vs 67.7 ± 20.5 mL/min/1.73 m2), higher Society for Vascular Surgery comorbidity score (10.9 ± 4.3 vs 8.2 ± 4.7) and calcium channel blocker therapy (50.0% vs 29.1%), and larger maximal aneurysm diameter (67.2 ± 16.9 vs 59.8 ± 9.8 mm) (all P < .05). Thirty-day mortality was higher in the proteinuria group (10.0% vs 1.3%; P = .03). Overall survival at 1 and 5 years was significantly lower for those with proteinuria (71.5% vs 92.3% and 29.5% vs 68.1%; log-rank P < .001). On multivariable analysis, preoperative proteinuria was independently associated with over threefold higher hazard of mortality (hazard ratio [HR]: 3.21, 95% confidence interval [CI]: 1.66-6.20; P < .001), whereas preoperative eGFR was not predictive (HR: 0.99, 95% CI: 0.98-1.01; P = .28). Additional significant predictors included chronic obstructive pulmonary disease (HR: 2.04), older age (HR: 1.05), and larger maximal aneurysm diameter (HR: 1.03; all P < .05).

CONCLUSIONS

In our 10-year experience with FEVAR, preoperative proteinuria was observed in 17% of patients and was significantly associated with worse survival. In this cohort, proteinuria was independently associated with all-cause mortality, whereas eGFR was not, suggesting that urinalysis may provide an additional simple metric for risk-stratifying patients before FEVAR.

Changes in proteinuria and the associated risks of ischemic heart disease, acute myocardial infarction, and angina pectoris in Korean population

OBJECTIVES

Proteinuria is widely used to predict cardiovascular risk. However, there is insufficient evidence to predict how changes in proteinuria may affect the incidence of cardiovascular disease.

METHODS

The study included 265,236 Korean adults who underwent health checkups in 2003-2004 and 2007-2008. They were categorized into 4 groups based on changes in proteinuria (negative: negative → negative; resolved: proteinuria ≥1+ → negative; incident: negative → proteinuria ≥1+; persistent: proteinuria ≥1+ → proteinuria ≥1+). We conducted 6 years of follow-up to identify the risks of developing ischemic heart disease (IHD), acute myocardial infarction (AMI), and angina pectoris according to changes in proteinuria. A multivariate Cox proportional-hazards model was used to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident IHD, AMI, and angina pectoris.

RESULTS

The IHD risk (expressed as HR [95% CI]) was the highest for persistent proteinuria, followed in descending order by incident and resolved proteinuria, compared with negative proteinuria (negative: reference, resolved: 1.211 [95% CI, 1.104 to 1.329], incident: 1.288 [95% CI, 1.184 to 1.400], and persistent: 1.578 [95% CI, 1.324 to 1.881]). The same pattern was associated with AMI (negative: reference, resolved: 1.401 [95% CI, 1.048 to 1.872], incident: 1.606 [95% CI, 1.268 to 2.035], and persistent: 2.069 [95% CI, 1.281 to 3.342]) and angina pectoris (negative: reference, resolved: 1.184 [95% CI, 1.065 to 1.316], incident: 1.275 [95% CI, 1.160 to 1.401], and persistent: 1.554 [95% CI, 1.272 to 1.899]).

CONCLUSIONS

Experiencing proteinuria increased the risks of IHD, AMI, and angina pectoris even after proteinuria resolved.

Association of proteinuria and risk of incident atrial fibrillation in the general population: A prospective study of Kailuan study participants

BACKGROUND

Proteinuria is a well-known cardiovascular risk factor, but whether it independently increases the risk for atrial fibrillation (AF) in Chinese population is unknown. To address this deficiency, herein, we investigated the association between proteinuria detected using urine dipstick test and the risk of AF.

METHODS

This was a prospective cohort study of Kailuan study participants who underwent the 2006-2007 and 2010-2011 health checkups and was free from AF. Participants were classified into four groups based on the level of proteinuria: [-, trace (±), 1+, ≥2+]. The outcome was incident AF as confirmed by 12-lead electrocardiography.

RESULTS

During a median of 11.90 years of follow-up, we documented 514 incident AF cases among 60,599 participants. Proteinuria was found in 6302 (10.40%) participants. Relative to participants without proteinuria at the baseline, those with proteinuria (≥2+) had an 83.9% higher risk (95% confidence interval [CI], 1.073-3.154, p = .0267) of developing AF, after adjusted for confounding variables. The result was consistent in the sensitivity analysis. Compared to consistently negative proteinuria, the risk of AF significantly increased in the aggravated proteinuria group (hazard ratio [HR] 1.552, 95% CI 1.140-2.114) and the persistent proteinuria group (HR 2.485, 95% CI 1.414-4.366). Among participants with resolved proteinuria (from positive to negative), the risk of incident AF was not significantly increased compared to those with persistently negative proteinuria (HR 1.300, 95% CI 0.743-2.276).

CONCLUSIONS

Proteinuria could be a modifiable risk factor for predicting AF development. Knowing the presence of proteinuria may improve risk stratification for decision-making about AF prevention.

Sex differences in impact of cumulative systolic blood pressure from childhood to adulthood on albuminuria in midlife: a 30-year prospective cohort study

BACKGROUND AND OBJECTIVES

Albuminuria is recognized as being a predictor of cardiovascular and renal disease. We aimed to identify the impact of the long-term burden and trends of systolic blood pressure on albuminuria in midlife, as well as to explore sex differences concerning this relationship.

METHODS

This longitudinal study consisted of 1,683 adults who had been examined 4 or more times for blood pressure starting in childhood, with a follow-up time period of 30 years. The cumulative effect and longitudinal trend of blood pressure were identified by using the area under the curve (AUC) of individual systolic blood pressure measurement with a growth curve random effects model.

RESULTS

Over 30 years of follow-up, 190 people developed albuminuria, including 53.2% males and 46.8% females (aged 43.39 ± 3.13 years in the latest follow-up). The urine albumin-to-creatinine ratio (uACR) values increased as the total and incremental AUC values increased. Additionally, women had a higher albuminuria incidence in the higher SBP AUC groups than men do (13.3% for men vs. 33.7% for women). Logistic regression showed that the ORs of albuminuria for males and females in the high total AUC group were 1.34 (0.70-2.60) and 2.94 (1.50-5.74), respectively. Similar associations were found in the incremental AUC groups.

CONCLUSIONS

Higher cumulative SBP was correlated with higher uACR levels and a risk of albuminuria in middle age, especially in women. The identification and control of cumulative SBP levels from an early age may assist in reducing the incidences of renal and cardiovascular disease for individuals in later life.

Quantifying Podocyte Number in a Small Sample Size of Glomeruli with CUBIC to Evaluate Podocyte Depletion of db/db Mice

The loss of podocyte is crucial for diagnosis and prognosis of diabetic kidney disease, whereas commonly two-dimensional methods for quantifying podocyte number existed with issues of low fidelity and accuracy. In this study, clear, unobstructed brain imaging cocktails and computational analysis (CUBIC), one of three-dimensional optical clearing approaches, was used which combines tissue clearing, immunolabeling, and a light-sheet microscope to image and evaluate podocytes in C57BL/6 (C57) and db/db mice. We discovered that 77 podocytes per glomerulus were in C57 mice. On the subject of db/db mice, there were 74 podocytes by the age of 8 w, 72 podocytes by the age of 12 w, and 66 podocytes by the age of 16 w, compared with 76 podocytes in the control group, suggesting that there was a significant decrease in podocyte number in db/db mice with the age of 16 w, showing a trend which positively correlated to the deterioration of kidney function. Sample size estimation using the PASS software revealed that taking 5%, 7.5%, and 10% of the mean podocyte number per glomerulus as the statistical allowable error and 95% as total confidence interval, 33, 15, and 9 glomeruli were independently needed to be sampled in C57 mice to represent the overall glomeruli to calculate podocyte number. Furthermore, in the control group of db/db mice, 36, 18, and 11 glomeruli were needed, compared with 46, 24, and 14 glomeruli in db/db mice by the age of 8 w, 43, 21, and 12 glomeruli by the age of 12 w, and 52, 27, and 16 by the age of 16 w. These findings indicated that precise quantification of podocyte number could judge the progression of diabetic kidney disease. In addition, a small number of glomeruli could be actually representative of the whole sample size, which indicated apparent practicability of CUBIC for clinical use.

Renal function is associated with one-month and one-year mortality in patients with intracerebral hemorrhage

OBJECTIVE

This study evaluated short-term (1-month) and long-term (1-year) mortality risks associated with the glomerular filtration rate (eGFR) on admission for patients with intracerebral hemorrhage.

METHODS

From the Taiwan Stroke Registry data from April 2006 to December 2016, we identified and stratified patients with intracerebral hemorrhage into five subgroups by the eGFR level on admission: ≥90, 60-89, 30-59, 15-29, and <15 mL/min/1.73 m2 or on dialysis. Risks for 1-month and 1-year mortality after intracerebral hemorrhage were compared by the eGFR levels.

RESULTS

Both the 1-month and 1-year mortality rates progressively increased with the decrease in eGFR levels. The 1-month mortality rate in patients with eGFR < 15 mL/min/1.73 m2 or on dialysis was approximately 5.5-fold greater than that in patients with eGFR ≥ 90 mL/min/1.73 m2 (8.31 versus 1.50 per 1000 person-days), with an adjusted hazard ratio (HR) of 4.59 [95% confidence interval (CI) = 2.71-7.78]. Similarly, the 1-year mortality in patients with eGFR < 15 mL/min/1.73 m2 or on dialysis was 7.5 times that in patients with eGFR ≥ 90 mL/min/1.73 m2 (2.34 versus 0.31 per 1000 person-days), with an adjusted HR of 4.54 (95% CI 2.95-6.98).

CONCLUSION

Impairment of renal function is an independent risk factor for mortality in patients with intracerebral hemorrhage in a gradual way. The eGFR level is a prognostic indicator for patients with intracerebral hemorrhage.

Trimethylamine, a gut bacteria metabolite and air pollutant, increases blood pressure and markers of kidney damage including proteinuria and KIM-1 in rats

Background

Trimethylamine oxide (TMAO) is a biomarker in cardiovascular and renal diseases. TMAO originates from the oxidation of trimethylamine (TMA), a product of gut microbiota and manufacturing industries-derived pollutant, by flavin monooxygenases (FMOs). The effect of chronic exposure to TMA on cardiovascular and renal systems is undetermined.

Methods

Metabolic, hemodynamic, echocardiographic, biochemical and histopathological evaluations were performed in 12-week-old male SPRD rats receiving water (controls) or TMA (200 or 500 µM/day) in water for 18 weeks. TMA and TMAO levels, the expression of FMOs and renin-angiotensin system (RAS) genes were evaluated in various tissues.

Results

In comparison to controls, rats receiving high dose of TMA had significantly increased arterial systolic blood pressure (126.3 ± 11.4 vs 151.2 ± 19.9 mmHg; P = 0.01), urine protein to creatinine ratio (1.6 (1.5; 2.8) vs 3.4 (3.3; 4.2); P = 0.01), urine KIM-1 levels (2338.3 ± 732.0 vs. 3519.0 ± 953.0 pg/mL; P = 0.01), and hypertrophy of the tunica media of arteries and arterioles (36.61 ± 0.15 vs 45.05 ± 2.90 µm, P = 0.001 and 18.44 ± 0.62 vs 23.79 ± 2.60 µm, P = 0.006; respectively). Mild degeneration of renal bodies with glomerulosclerosis was also observed. There was no significant difference between the three groups in body weight, water-electrolyte balance, echocardiographic parameters and RAS expression. TMA groups had marginally increased 24 h TMA urine excretion, whereas serum levels and 24 h TMAO urine excretion were increased up to 24-fold, and significantly increased TMAO levels in the liver, kidneys and heart. TMA groups had lower FMOs expression in the kidneys.

Conclusions

Chronic exposure to TMA increases blood pressure and increases markers of kidney damage, including proteinuria and KIM-1. TMA is rapidly oxidized to TMAO in rats, which may limit the toxic effects of TMA on other organs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03687-y.

Therapeutic angiogenesis-based strategy for peripheral artery disease

Peripheral artery disease (PAD) poses a great challenge to society, with a growing prevalence in the upcoming years. Patients in the severe stages of PAD are prone to amputation and death, leading to poor quality of life and a great socioeconomic burden. Furthermore, PAD is one of the major complications of diabetic patients, who have higher risk to develop critical limb ischemia, the most severe manifestation of PAD, and thus have a poor prognosis. Hence, there is an urgent need to develop an effective therapeutic strategy to treat this disease. Therapeutic angiogenesis has raised concerns for more than two decades as a potential strategy for treating PAD, especially in patients without option for surgery-based therapies. Since the discovery of gene-based therapy for therapeutic angiogenesis, several approaches have been developed, including cell-, protein-, and small molecule drug-based therapeutic strategies, some of which have progressed into the clinical trial phase. Despite its promising potential, efforts are still needed to improve the efficacy of this strategy, reduce its cost, and promote its worldwide application. In this review, we highlight the current progress of therapeutic angiogenesis and the issues that need to be overcome prior to its clinical application.

Proteinuria as a Nascent Predictor of Frailty Among People With Metabolic Syndrome: A Retrospective Observational Study

Frailty is a commonly occurring geriatric condition that increases the risk of adverse health outcomes. The factors and predictors behind frailty are not yet well understood. A better understanding of these factors can enable prevention of frailty in elderly patients. The objective of this study was to determine the association between proteinuria and frailty in US individuals with metabolic syndrome (MetS). Data from the National Health and Nutrition Examination Survey III (NHANES III, 1988–1994) conducted by the National Center for Health Statistics of the Centers for Disease Control and Prevention. This is a cross-sectional study, and proteinuria and frailty were measured only once at enrollment. The study included 2,272 participants with MetS aged 40–90 years from the NHANES III. The participants underwent assessments to evaluate frailty and frailty components (low body weight, weakness, exhaustion, low physical activity, and slow walking). Proteinuria was represented as albumin-to-creatinine ratio (ACR) (mg/g) and divided into tertiles: T1-normal range (ACR <30 mg/g), T2-microalbuminuria (ACR 30–299 mg/g), and T3-macroalbuminuria (ACR ≥ 300 mg/g). We applied multiple logistic regression to determine the odds ratios (ORs) of frailty for T2 vs. T1 and T3 vs. T1 in both sexes. In the adjusted analysis for male participants, the ORs of frailty for T2 and T3 vs. T1 were 3.106 (95% confidence interval [CI] = 1.078–8.948, P = 0.036) and 14.428 (95% CI = 4.231–49.193, P < 0.001), respectively. For female participants, the ORs of frailty for T2 and T3 vs. T1 were 1.811 (95% CI = 1.071–3.063, P = 0.027) and 2.926 (95% CI = 1.202–7.124, P = 0.018), respectively. The positive association between T2 and T3 vs. T1, and frailty were statistically significant. The trends of higher likelihood of every frailty component were also statistically significant across increasing tertiles of proteinuria after multiple levels of adjustment for covariates (P < 0.05). Increased proteinuria levels were positively associated with frailty and each frailty component. Proteinuria might be a useful maker for frailty in individuals with MetS.

Meta-Analysis of the Effectiveness and Safety of Glucocorticoid for the Treatment of IgA Kidney Disease

Purpose

To explore the effect of glucocorticoid on immune globulin A (IgA) nephropathy by meta-analysis.

Method

Search the data and literature libraries of ScienceDirect, EBSCO, Wiley, PubMed, CBMdisc, and CNKI and collect the literature on the treatment of IgA nephropathy with glucocorticoids as randomized controlled trials published at home and abroad from 1995 to 2021. The standardized mean difference (SMD) and 95% confidence interval (CI) were calculated by fixed-effects model. RevMan 5.0 software was used for meta-analysis of the subgroups of overall curative effect, different degree of proteinuria, different course of treatment, different creatinine level, and combined ACEI.

Result

① The overall efficacy of glucocorticoid in the treatment of IgA nephropathy was better than that in the control group (P = 0.00001). ② The efficacy of glucocorticoid treatment in patients with IgA nephropathy with proteinuria greater than 1.50 g/d and less than 1.50 g/d was better than that in the control group (P < 0.01). ③ For IgA nephropathy patients with serum creatinine less than 1.50 mg/dl, the curative effect of glucocorticoid treatment was better than that of the control group (P < 0.01). ④ The effects of short-term treatment (<1 year) and long-term treatment (≥1 year) with glucocorticoid were better than those in the control group (P < 0.01). ⑤ The effect of hormone combined with ACEI drugs on IgA nephropathy was more significant (P < 0.01).

Conclusion

The overall efficacy of glucocorticoid in the treatment of IgA nephropathy is accurate. Hormone treatment is effective for different degrees of IgA nephropathy. Considering that there is no significant effect on the efficacy of different courses of treatment, it is suggested that the course of hormone treatment can be appropriately shortened. Hormone combined with angiotensin-converting enzyme inhibitors (ACEI) can reduce proteinuria more effectively than ACEI drugs alone.

A fluorescent sensor recognized by the FA1 site for highly sensitive detection of HSA

Human serum albumin (HSA), as the most abundant protein in blood plasma, plays a crucial role in many physiological processes. The abnormal HSA level in serum or in urine is often associated with various diseases. Therefore, to achieve highly sensitive and selective quantification of HSA is of great importance for disease diagnosis and preventive medicine. Herein, an HSA-selective light-up fluorescent sensor, DCM-ML, was successfully developed for quantitative detection of HSA. DCM-ML exhibited good (photo-) stability and strong fluorescence enhancement around 630 nm in the presence of HSA in complex samples containing numerous biological analytes. Upon addition of HSA into DCM-ML containing solution, a good linear relationship (R² > 0.99) between the fluorescence intensity of DCM-ML and HSA concentration from 0 to 0.08 mg/mL was obtained with the detection limit of 0.25 μg/mL. The sensing mechanism of the sensor towards HSA was demonstrated to be via recognition in the fatty acid site 1 (FA1), instead of the most reported binding sites (Sudlow I and II) in HSA, for the first time, by both the displacement experiments and molecular docking simulation. Thus, DCM-ML can also be assumed as a potential FA1 site-binding marker for examining drugs binding to the FA1 site in HSA. At last, the utilization of sensor DCM-ML for quantification and validation of HSA in urine samples and cell culture medium was effectively demonstrated. Therefore, the development of DCM-ML should find great application potentials in the fields of analytical chemistry and clinical medicine as a highly sensitive HSA sensor.

Introduction to Nephrocardiology

The interaction between nephrology and cardiovascular medicine is much broader than the cardiorenal syndrome. Many different aspects of cardiovascular medicine are interconnected with and substantially influenced by the conditions that fall into the realm of nephrology, and vice versa. Those aspects include pathophysiology, risk factors, epidemiology, prognosis, prevention, diagnosis, monitoring, and therapy. Discovery of the interconnected areas and development of appropriate knowledge and skill to optimally approach those circumstances can improve the quality of care and outcome of a large population of patients. Therefore, establishment of the distinct subspeciality of nephrocardiology is imperative.

Diabetic patients with chronic kidney disease: Non-invasive assessment of cardiovascular risk

The prevalence and burden of diabetes mellitus and chronic kidney disease on global health and socioeconomic development is already heavy and still rising. Diabetes mellitus by itself is linked to adverse cardiovascular events, and the presence of concomitant chronic kidney disease further amplifies cardiovascular risk. The culmination of traditional (male gender, smoking, advanced age, obesity, arterial hypertension and dyslipidemia) and non-traditional risk factors (anemia, inflammation, proteinuria, volume overload, mineral metabolism abnormalities, oxidative stress, etc.) contributes to advanced atherosclerosis and increased cardiovascular risk. To decrease the morbidity and mortality of these patients due to cardiovascular causes, timely and efficient cardiovascular risk assessment is of huge importance. Cardiovascular risk assessment can be based on laboratory parameters, imaging techniques, arterial stiffness parameters, ankle-brachial index and 24 h blood pressure measurements. Newer methods include epigenetic markers, soluble adhesion molecules, cytokines and markers of oxidative stress. In this review, the authors present several non-invasive methods of cardiovascular risk assessment in patients with diabetes mellitus and chronic kidney disease.

Replacing centrifugation with mixing in urine analysis enriches protein pool in the urine samples

Urine is the basic diagnostic material, easy to collect, not requiring invasive approach. During standard procedure the urine samples are centrifuged and the supernatant analysed physically, biochemically, and microscopically. The centrifugation step removes proteins including those forming aggregates especially in the state of illness and after transplantation. Here, we analysed the effect of urine centrifuging on specific protein content in urine samples obtained from cardiovascular patients (CVD) and after kidney or liver transplantation. We tested homogeneous whole urine samples, standardly centrifuge one, and the pellet after centrifuging. Protein content was examined using Western blot analysis and mass spectrometry (MS) of samples from CVD patients or the one after transplantation. The average of 21% proteins from non-centrifuged samples were found in the pellet removed after standard centrifugation. MS analysis confirmed that diagnostically important proteins were located there in. In 90% of cases whole urine samples contained more proteins than standard supernatant, among them e.g. proteins involved in immunological response like immunoglobulins and complement compounds secreted by leucocytes. Replacing centrifuging with intensive mixing of urine samples provides a method of enriching the samples with proteins removed during standard procedure, thus increasing possibility of finding new biomarkers for diseases undiagnosable with classic urine analysis.

CALINCA-A Novel Pipeline for the Identification of lncRNAs in Podocyte Disease

Diseases of the renal filtration unit-the glomerulus-are the most common cause of chronic kidney disease. Podocytes are the pivotal cell type for the function of this filter and focal-segmental glomerulosclerosis (FSGS) is a classic example of a podocytopathy leading to proteinuria and glomerular scarring. Currently, no targeted treatment of FSGS is available. This lack of therapeutic strategies is explained by a limited understanding of the defects in podocyte cell biology leading to FSGS. To date, most studies in the field have focused on protein-coding genes and their gene products. However, more than 80% of all transcripts produced by mammalian cells are actually non-coding. Here, long non-coding RNAs (lncRNAs) are a relatively novel class of transcripts and have not been systematically studied in FSGS to date. The appropriate tools to facilitate lncRNA research for the renal scientific community are urgently required due to a row of challenges compared to classical analysis pipelines optimized for coding RNA expression analysis. Here, we present the bioinformatic pipeline CALINCA as a solution for this problem. CALINCA automatically analyzes datasets from murine FSGS models and quantifies both annotated and de novo assembled lncRNAs. In addition, the tool provides in-depth information on podocyte specificity of these lncRNAs, as well as evolutionary conservation and expression in human datasets making this pipeline a crucial basis to lncRNA studies in FSGS.

Cardiovascular disease risk assessment in patients with familial Mediterranean fever related renal amyloidosis

Chronic inflammation and proteinuria is a risk factor for cardiovascular disease (CVD) in patients with chronic kidney diseases and rheumatologic disorders. Our aim was to investigate the CVD events (CVDEs) and survival between the patients with FMF-related AA amyloidosis and glomerulonephropathies (GN) to define possible predictors for CVDEs. A prospective follow-up study with FMF-amyloidosis and glomerulonephropathy (GN) was performed and patients were followed for CVDEs. Flow-mediated dilatation (FMD), FGF-23, serum lipid, hsCRP levels, BMI and HOMA were assessed. A Cox regression analysis was performed to evaluate the risk factors for CVDEs. There were 107 patients in the FMF-amyloidosis group and 126 patients with GN group. Forty-seven CVDEs were observed during the 4.2-years follow up; all 28 patients in the FMF-amyloidosis group and 14/19 patients with GN developed CVDEs before the age of 40 (p = 0.002). CVD mortality was 2.8 times higher (95% CI 1.02–7.76) in patients with FMF-amyloidosis. Across both groups, FMD and FGF23 (p < 0.001) levels were independently associated with the risk of CVDEs. Patients with FMF-amyloidosis are at increased risk of early CVDEs with premature mortality age. FGF 23, FMD and hsCRP can stratify the risk of early CVD in patients with FMF-related AA amyloidosis.

Urinary Exosomal MicroRNA Signatures in Nephrotic, Biopsy-Proven Diabetic Nephropathy

Diabetic kidney disease (DKD) is the leading cause of chronic kidney disease (CKD). Elucidating the mechanisms underlying proteinuria in DKD is crucial because it is a common problem in DKD-related mortality and morbidity. MicroRNAs (miRs) associated with DKD have been detected in experimental diabetes models and in patients with both diabetes and CKD. Here, we aimed to investigate pathologic miRs in diabetic nephropathy (DN) by prospectively following six nephrotic, biopsy-proven isolated DN patients (enrolled between August 2015 and July 2017) for one year. The urinary exosomes were isolated at the time of the biopsy and the contained miRs were analyzed by next-generation sequencing. The results were compared to the control group, composed of age-, gender-, and CKD stage-matched patients with proteinuric CKD who did not present diabetes. Among the 72 identified miRs, we investigated eight (miR-188-5p, miR-150-3p, miR-760, miR-3677-3p, miR-548ah-3p, miR-548p, miR-320e, and miR-23c) exhibiting the strongest upregulation (13–15 fold) and two (miR-133a-3p and miR-153-3p) with the strongest downregulation (7–9 fold). The functional analysis of these miRs showed that they were involved in known and novel pathways of DN, supporting their pathologic roles. The bioinformatics-based prediction of the target genes of these miRs will inspire future research on the mechanisms underlying DN pathogenesis.

Association of Prediabetes With CKD Progression and Adverse Cardiovascular Outcomes: An Analysis of the CRIC Study

PURPOSE

Despite our understanding of diabetes as an established risk factor for progressive kidney disease and cardiac complications, the prognostic significance of prediabetes in patients with chronic kidney disease (CKD) remains largely unknown.

METHODS

Participants of the Chronic Renal Insufficiency Cohort (CRIC) were categorized as having normoglycemia, prediabetes, or diabetes according to fasting plasma glucose, glycated hemoglobin A1c (HbA1c), and treatment with antidiabetic drugs at baseline. Unadjusted and adjusted proportional hazards models were fit to estimate the association of prediabetes and diabetes (versus normoglycemia) with: (1) composite renal outcome (end-stage renal disease, 50% decline in estimated glomerular filtration rate to ≤ 15 mL/min/1.73 m2, or doubling of urine protein-to-creatinine ratio to ≥ 0.22 g/g creatinine); (2) composite cardiovascular (CV) outcome (congestive heart failure, myocardial infarction or stroke); and (3) all-cause mortality.

RESULTS

Of the 3701 individuals analyzed, 945 were normoglycemic, 847 had prediabetes and 1909 had diabetes. The median follow-up was 7.5 years. Prediabetes was not associated with the composite renal outcome (adjusted hazard ratio [aHR] 1.13; 95% confidence interval [CI], 0.96-1.32; P = 0.14), but was associated with proteinuria progression (aHR 1.23; 95% CI, 1.03-1.47; P = 0.02). Prediabetes was associated with a higher risk of the composite CV outcome (aHR 1.38; 95% CI, 1.05-1.82; P = 0.02) and a trend towards all-cause mortality (aHR 1.28; 95% CI, 0.99-1.66; P = 0.07). Participants with diabetes had an increased risk of the composite renal outcome, the composite CV outcome, and all-cause mortality.

CONCLUSIONS

In individuals with CKD, prediabetes was not associated with composite renal outcome, but was associated with an increased risk of proteinuria progression and adverse CV outcomes.

Intravenous administration of iPS-MSCSPIONs mobilized into CKD parenchyma and effectively preserved residual renal function in CKD rat

This study traced intravenously administered induced pluripotent stem cell (iPSC)‐derived mesenchymal stem cells (MSC) and assessed the impact of iPSC‐MSC on preserving renal function in SD rat after 5/6 nephrectomy. The results of in vitro study showed that FeraTrack™Direct contrast particles (ie intracellular magnetic labelling) in the iPSC‐MSC (ie iPS‐MSC^SPIONs) were clearly identified by Prussian blue stain. Adult‐male SD rats (n = 40) were categorized into group 1 (SC), group 2 [SC + iPS‐MSC^SPIONs (1.0 × 10⁶cells)/intravenous administration post‐day‐14 CKD procedure], group 3 (CKD), group 4 [CKD + iPS‐MSC^SPIONs (0.5 × 10⁶cells)] and group 5 [CKD + iPS‐MSC^SPIONs (1.0 × 10⁶cells)]. By day‐15 after CKD induction, abdominal MRI demonstrated that iPS‐MSC^SPIONs were only in the CKD parenchyma of groups 4 and 5. By day 60, the creatinine level/ratio of urine protein to urine creatinine/kidney injury score (by haematoxylin and eosin stain)/fibrotic area (Masson's trichrome stain)/IF microscopic finding of kidney injury molecule‐1 expression was lowest in groups 1 and 2, highest in group 3, and significantly higher in group 4 than in group 5, whereas IF microscopic findings of podocyte components (ZO‐1/synaptopodin) and protein levels of anti‐apoptosis ((Bad/Bcl‐xL/Bcl‐2) exhibited an opposite pattern to creatinine level among the five groups (all P < .0001). The protein expressions of cell‐proliferation signals (PI3K/p‐Akt/m‐TOR, p‐ERK1/2, FOXO1/GSK3β/p90RSK), apoptotic/DNA‐damage (Bax/caspases8‐10/cytosolic‐mitochondria) and inflammatory (TNF‐α/TNFR1/TRAF2/NF‐κB) biomarkers displayed an identical pattern to creatinine level among the five groups (all P < .0001). The iPS‐MSC^SPIONs that were identified only in CKD parenchyma effectively protected the kidney against CKD injury.

Preoperative proteinuria is associated with increased rates of acute kidney injury after partial nephrectomy

Purpose

We investigated the association between preoperative proteinuria and early postoperative renal function after robotic partial nephrectomy (RPN).

Patients and Methods

We retrospectively reviewed 1121 consecutive RPN cases at a single academic center from 2006 to 2016. Patients without pre-existing CKD (eGFR≥60 mL/min/1.73m²) who had a urinalysis within 1-month prior to RPN were included. The cohort was categorized by the presence or absence of preoperative proteinuria (trace or greater (≥1+) urine dipstick), and groups were compared in terms of clinical and functional outcomes. The incidence of acute kidney injury (AKI) was assessed using RIFLE criteria. Univariate and multivariable models were used to identify factors associated with postoperative AKI.

Results

Of 947 patients, 97 (10.5%) had preoperative proteinuria. Characteristics associated with preoperative proteinuria included non-white race (p<0.01), preoperative diabetes (p<0.01) and hypertension (HTN) (p<0.01), higher ASA (p<0.01), higher BMI (p<0.01), and higher Charlson score (p<0.01). The incidence of AKI was higher in patients with preoperative proteinuria (10.3% vs. 4.6%, p=0.01). The median eGFR preservation measured within one month after surgery was lower (83.6% vs. 91%, p=0.04) in those with proteinuria; however, there were no significant differences by 3 months after surgery or last follow-up visit. Independent predictors of AKI were high BMI (p<0.01), longer ischemia time (p<0.01), and preoperative proteinuria (p=0.04).

Conclusion

Preoperative proteinuria by urine dipstick is an independent predictor of postoperative AKI after RPN. This test may be used to identify patients, especially those without overt CKD, who are at increased risk for developing AKI after RPN.

Chronic Kidney Disease as a Risk Factor for Heart Failure With Preserved Ejection Fraction: A Focus on Microcirculatory Factors and Therapeutic Targets

Heart failure (HF) and chronic kidney disease (CKD) co-exist, and it is estimated that about 50% of HF patients suffer from CKD. Although studies have been performed on the association between CKD and HF with reduced ejection fraction (HFrEF), less is known about the link between CKD and heart failure with preserved ejection fraction (HFpEF). Approximately, 50% of all patients with HF suffer from HFpEF, and this percentage is projected to rise in the coming years. Therapies for HFrEF are long established and considered quite successful. In contrast, clinical trials for treatment of HFpEF have all shown negative or disputable results. This is likely due to the multifactorial character and the lack of pathophysiological knowledge of HFpEF. The typical co-existence of HFpEF and CKD is partially due to common underlying comorbidities, such as hypertension, dyslipidemia and diabetes. Macrovascular changes accompanying CKD, such as hypertension and arterial stiffening, have been described to contribute to HFpEF development. Furthermore, several renal factors have a direct impact on the heart and/or coronary microvasculature and may underlie the association between CKD and HFpEF. These factors include: (1) activation of the renin-angiotensin-aldosterone system, (2) anemia, (3) hypercalcemia, hyperphosphatemia and increased levels of FGF-23, and (4) uremic toxins. This review critically discusses the above factors, focusing on their potential contribution to coronary dysfunction, left ventricular stiffening, and delayed left ventricular relaxation. We further summarize the directions of novel treatment options for HFpEF based on the contribution of these renal drivers.

Extracellular Vesicles from Albumin-Induced Tubular Epithelial Cells Promote the M1 Macrophage Phenotype by Targeting Klotho

Albumin absorbed by renal tubular epithelial cells induces inflammation and plays a key role in promoting diabetic kidney disease (DKD) progression. Macrophages are prominent inflammatory cells in the kidney, and their role there is dependent on their phenotypes. However, whether albuminuria influences macrophage phenotypes and underlying mechanisms during the development of DKD is still unclear. We found that M1 macrophage-related markers were increased in diabetes mellitus (DM) mouse renal tissues with the development of DKD, and coculture of extracellular vesicles (EVs) from human serum albumin (HSA)-induced HK-2 cells with macrophages induced macrophage M1 polarization in the presence of lipopolysaccharide (LPS). Through a bioinformatic analysis, miR-199a-5p was selected and found to be increased in EVs from HSA-induced HK-2 cells and in urinary EVs from DM patients with macroalbuminuria. Tail-vein injection of DM mice with EVs from HSA-induced HK-2 cells induced kidney macrophage M1 polarization and accelerated the progression of DKD through miR-199a-5p. miR-199a-5p exerted its effect by targeting Klotho, and Klotho induced macrophage M2 polarization through the Toll-like receptor 4 (TLR4) pathway both in vivo and in vitro. In summary, miR-199a-5p from HSA-stimulated HK-2 cell-derived EVs induces M1 polarization by targeting the Klotho/TLR4 pathway and further accelerates the progression of DKD.

Causes of late transplant failure in cyclosporine-treated kidney allograft recipients

BACKGROUND

There is little information about very long-term outcomes of kidney allograft recipients exposed to calcineurin inhibitors.

METHODS

In this single-centre retrospective study with 20-year follow-up, we analyzed data from 644 patients who underwent primary renal transplantation between 1983 and 1993. Participants were treated with a cyclosporine-based immunosuppressive scheme and had allograft function at 1 year.

RESULTS

After 20 years, 15.2% patients died, 39.7% experienced allograft loss, 26.8% were alive with a functioning transplant, and 18.2% were lost to follow-up. Cardiovascular disease (30.8%), malignancy (26.6%) and infection (17.0%) were the main causes of death. Age, new-onset proteinuria > 1 g/day, major acute cardiovascular event (MACE), and malignancy were independent predictors of mortality at time-dependent multivariate analysis. Chronic rejection (63.3%), recurrent glomerulonephritis (14.0%), and nonspecific interstitial fibrosis/tubular atrophy (13.2%) were the leading cause of allograft loss. Basal disease, hepatitis C, difference between 1 year and nadir serum creatinine, new-onset proteinuria > 1 g/day, and MACE were independent predictors of transplant failure. Among patients with 20-year allograft function, we recorded the following complications: hypertension (85%), malignancy (13%), diabetes (9%), and cardiovascular disease (9%). Median serum creatinine and proteinuria were 1.4 mg/dL and 0.6 g/day, respectively.

CONCLUSIONS

Prolonged use of cyclosporine may expose to several dose-related adverse events and may contribute to the development of allograft dysfunction but it does not necessarily cause relentless, progressive transplant failure if patients are carefully and consistently monitored during the follow-up.

Two-year changes in proteinuria and risk for myocardial infarction in patients with hypertension: a prospective cohort study

OBJECTIVE

To assess whether changes in proteinuria are associated with the incidence of myocardial infarction (MI) in patients with hypertension.

METHODS

The Kailuan study was a prospective longitudinal cohort study on cardiovascular risk factors and events. Hazard ratios with 95% confidence intervals (CIs) were calculated using Cox regression models.

RESULTS

A total of 24 926 hypertensive patients (mean age: 55.2 ± 10.9 years) without previous MI were included. After a mean follow-up of 6.8 years, 382 (1.5%) individuals developed MI. Participants with proteinuria at baseline had a 60% higher risk for developing MI as compared with participants without proteinuria at baseline (hazard ratio: 1.60, 95% CI: 1.12-2.29) after adjusting for dyslipidemia, diabetes mellitus and other cardiovascular risk factors. Compared with participants without proteinuria, individuals with incident proteinuria or persistent proteinuria during the follow-up had 54 and 141% higher risks for developing MI, respectively (hazard ratio: 1.54, 95% CI: 1.14-2.09 and hazard ratio: 2.41, 95% CI: 1.59-3.66; all P < 0.05).

CONCLUSION

Proteinuria is associated with an increased incidence of MI, but the association is likely to be underestimated if baseline measurements of proteinuria are used. Measures of changes in proteinuria, particular persistent proteinuria, are more likely to reflect the lifetime risk for MI.

Association of renal hyperfiltration with incident proteinuria - A nationwide registry study

To elucidate the association between renal hyperfiltration (RHF) and incident proteinuria, the data from 11,559,520 Korean adults who had undergone health screenings ≥ 3 times between 2009 and 2014 and had glomerular filtration rate (GFR) ≥60 mL/min/1.73m2 and negative dipstick test for proteinuria at baseline, were retrospectively analyzed. GFR was estimated with the Chronic Kidney Disease Epidemiology Collaboration equation based on serum creatinine, and RHF was defined as GFR >95th percentile adjusted for sex, age, body size, and diabetes and/or hypertension medication. The adjusted hazard ratio (aHR) of incident proteinuria in the RHF was 1.083 (95% CI, 1.069~1.097) compared to that of the non-RHF with Cox regression model. The association between RHF and incident proteinuria was not only in diabetic but also in non-diabetic subjects. This association was not observed in women (p for interaction <0.001). A reverse J-shaped association was found between the adjusted GFR slope and aHR of incident proteinuria. Both lower and higher GFR were associated with incident proteinuria in men. In conclusion, RHF was associated with incident proteinuria in men. Clinical studies are necessary to study whether the alleviation of RHF can prevent incident proteinuria.

Any grade of relative overhydration is associated with long-term mortality in patients with Stages 4 and 5 non-dialysis chronic kidney disease

Background

Overhydration (OH) is associated with mortality in chronic kidney disease (CKD). A relative overhydration adjusted for extracellular water (OH/ECW) measured by bioimpedance >15% has shown an increased mortality risk in haemodialysis but few studies have been developed in advanced CKD. Our objective was to evaluate the effect of OH on mortality in patients with Stage 4 or 5 non-dialysis CKD.

Methods

We performed a prospective study of 356 patients enrolled in 2011 and followed up until 2016. At baseline we collected general characteristics, serum inflammatory and nutrition markers, cardiovascular events (CVEs) and body composition using bioimpedance spectroscopy. During a median follow-up of 50 (24–66) months we collected mortality data.

Results

The mean creatinine was 3.5 ± 1.3 mg/dL, median proteinuria was 0.5 [interquartile range (IQR) 0.2–1.5] g/24 h, median OH was 0.6 (IQR −0.4–1.5) L and mean relative OH (OH/ECW) was 2.3 ± 0.8%. We found that 32% of patients died. The univariate Cox analysis showed an association between mortality and age, diabetes, previous CVEs, Charlson comorbidity index, low albumin and pre-albumin, high C-reactive protein (CRP), low lean tissue and high OH/ECW. Multivariate Cox analysis confirmed an association between mortality and age {exp(B) 1.1 [95% confidence interval (CI) 1.0–1.3]; P = 0.001}, Charlson comorbidity index [exp(B) 1.1 (95% CI 1.0–1.2); P = 0.01], CRP [exp(B) 1.1 (95% CI 1.0–1.2); P = 0.04], OH/ECW [exp(B) 3.18 (95% CI 2.09–4.97); P = 0.031] and low lean tissue [exp(B) 0.82 (95% CI 0.69–0.98); P = 0.002]. Kaplan–Meier analysis confirmed higher mortality in patients with OH/ECW >0% (log rank 11.1; P = 0.001).

Conclusion

Any grade of relative OH measured by OH/ECW >0% is associated with long-term mortality in patients with Stage 4 or 5 non-dialysis CKD.

Periaortic Adipose Tissue Compared With Peribrachial Adipose Tissue Mass as Markers and Possible Modulators of Cardiometabolic Risk

Increased perivascular fat mass contributes to cardiometabolic risk (CMR). High peribrachial adipose tissue (PBAT) associates with insulin resistance independently of established CMR parameters. It is unknown to what extent periaortic adipose tissue (PAAT) may have a similar impact. In 95 participants, precise quantification of total adipose tissue, PBAT, PAAT, visceral adipose tissue (VAT), and liver fat (LF) content was performed by whole-body magnetic resonance imaging. Insulin sensitivity was determined by oral glucose tolerance test and carotid intima-media thickness (cIMT) by high-resolution ultrasound. In univariate analyses, PAAT correlated with PBAT (β = .65, P < .0001). A negative correlation of PAAT (β = -.35, P = .0002) and PBAT (β = -.43, P < .0001) with insulin sensitivity was observed. While in a stepwise forward regression analysis the relationship of PAAT with insulin sensitivity was no longer significant after adjustment for VAT, LF content, and other CMR factors ( P = 0.42), PBAT still correlated with insulin sensitivity ( r² = .35, P = .01). The association between PAAT and cIMT (β = .49, P < .0001) remained significant after adjustment for these variables ( r² = .42, P = .0001). Although PAAT and PBAT strongly correlate, PAAT is not associated with insulin resistance, but with cIMT. Therefore, PAAT and PBAT may act differently as possible modulators of insulin resistance and subclinical atherosclerosis.

Greater low-density lipoprotein cholesterol variability is associated with increased progression to dialysis in patients with chronic kidney disease stage 3

Increasing evidence suggests that lipid variability may be a predictor of cardiovascular events. However, few studies have evaluated the association between lipid variability and renal outcomes in patients with moderate-to-advanced chronic kidney disease (CKD). Therefore, the aims of this study were to assess whether lipid variability is associated with progression to dialysis in patients with CKD stage 3–5, and to evaluate the risk factors of lipid variability. This longitudinal study enrolled 725 patients with CKD stage 3–5. Intra-individual lipid variability was defined as the standard deviations (SDs) of lipid levels. The renal end-point was defined as commencing dialysis. During a mean follow-up period of 3.2 years, 208 patients (28.7%) started dialysis. The patients with CKD stage 3 with high low-density lipoprotein (LDL) cholesterol SD (per 1 mg/dL; hazard ratio, 1.035; 95% confidence interval, 1.003 to 1.067; p = 0.003) were associated with an increased risk of progression to dialysis, however this association was not seen in the patients with CKD stage 4 or 5. Furthermore, in the patients with CKD stage 3, a high urine protein-to-creatinine ratio (p < 0.001) and the use of statins (p < 0.001) were significantly associated with an increased LDL-cholesterol SD. Greater LDL-cholesterol variability was associated with an increased risk of progression to dialysis in patients with CKD stage 3, but not in those with CKD stage 4 or 5. These findings support the potential role of aggressive lipid control on clinical outcomes and highlight its importance in patients with CKD stage 3.

Cardiovascular risks in chronic kidney disease pediatric patients

One of the common factors for the premature death in children is advanced chronic kidney disease (CKD). Most often cardiovascular disease (CVD) is the reason for mortality. The cardiovascular (CV) morbidity starts early in the disease process and renal transplanted children (CKD-T) are also at risk. The present review is focused on the current views of the cardiovascular risks during CKD in pediatric patients. Variable data sources for the latest literature collection were explored which mainly included PubMed and Google Scholar. The most important risk factors for subclinical CVD were a young age, elevated BMI and systolic blood pressure z-scores as well as a low GFR and present albuminuria. Increasing blood pressure and BMI over follow-up were also important cardiac risk factors longitudinally. The present review concludes that altered cardiac function and remodeling are a concurrent part of the CKD process, start early in the disease development, and persist after renal transplantation. The findings suggest that children with CKD or CKD-T are at high risk for future CVD where younger patients with elevated BMI and slightly increased blood pressures, as well as present albuminuria, are those at greatest risk, thus indicating targets for future interventions.

Determination of the optimal target level of proteinuria in the management of patients with glomerular diseases by using different definitions of proteinuria

Proteinuria is a major determinant of adverse renal outcome, and its reduction slows renal progression in glomerular diseases. However, the optimal target of proteinuria in glomerular diseases is unclear, and discrepancies in the definition of proteinuria produce ambiguous findings. Here we investigated the optimal target of proteinuria by using different definitions of proteinuria. We analyzed 574 IgA nephropathy (IgAN), 175 membranous nephropathy (MGN), and 177 focal segmental glomerulosclerosis (FSGS) cases from 3 Korean kidney centers. We evaluated the impact of proteinuria on renal outcome with 2 definitions: time-average proteinuria (TAP) and time-varying proteinuria (TVP). The endpoint was renal progression, defined as a 50% decline in glomerular filtration rate or end-stage renal disease. During a median follow-up of 57.3 months, the primary outcome occurred in 54 patients with IgAN, 26 with MGN, and 30 with FSGS. Multivariate Cox regression using TAP indicated that there was a linear association between proteinuria and risk of renal progression in IgAN. However, moderate proteinuria was not associated with an increased risk of renal progression in MGN and FSGS. In contrast, the analysis by TVP showed that the risk significantly increased in proportion to proteinuria during follow-up in all 3 diseases. Our findings suggest that TVP-based model can delineate association between proteinuria and risk of renal progression better than TAP-based model, considering that TVP reflects the dynamic change of proteinuria over time. Thus, proteinuria reduction to the lowest possible level is required to improve renal outcomes in patients with glomerular diseases.

The association between insulin resistance and atrial fibrillation: A cross-sectional analysis from SPRINT (Systolic Blood Pressure Intervention Trial)

It is unclear whether metabolic syndrome (MetS) is associated with atrial fibrillation (AF) in an older population with greater cardiovascular risk, including those with chronic kidney disease. The authors investigated the association between MetS and AF in participants in SPRINT (Systolic Blood Pressure Intervention Trial). MetS was defined based on the Modified Third National Cholesterol Education Program. The baseline prevalence rate for MetS was 55%, while 8.2% of the participants had AF. In multivariate regression analyses, AF was not associated with presence of MetS in either chronic kidney disease or non-chronic kidney disease subgroups. Age, race, history of cardiovascular diseases, decreased triglycerides, decreased pulse pressure, and albuminuria remained significantly associated with AF risk. In contrast to the general population, MetS was not associated with AF in the older population with increased cardiovascular risk studied in SPRINT.

Proteinuria Detected by Urine Dipstick Test as a Risk Factor for Atrial Fibrillation: A Nationwide Population-Based Study

Proteinuria is one of the well-known risk factors for cardiovascular disease. However the impact of proteinuria on the incidence of atrial fibrillation (AF) is unclear. In this study, we investigated the association between proteinuria detected using urine dipstick test and the risk of AF. A total of 18,201,275 individuals were analyzed, who had no prior AF and had received biennial health checkups provided by the National Health Insurance Service between 2005 and 2008 in Korea. Incidences of AF were ascertained through the end of 2015. During a mean follow-up of 9.6 years, a total of 324,764 (1.8%) developed AF (1.86 per 1,000 person-years). In Cox regression models, proteinuria was associated with an increased risk of AF: adjusted HR and 95% CI of AF occurrence were 1.13 (1.10-1.16), 1.34 (1.31-1.38), 1.53 (1.48-1.58), 1.82 (1.71-1.94), and 1.86 (1.61-2.16) in individuals with trace, 1+, 2+, 3+, and 4+ proteinuria, respectively, compared with those without proteinuria. The result was consistent even after additional adjustment for estimated glomerular filtration rate. In addition, the risk of AF further increased or decreased according to the follow-up dipstick test results. Thus, proteinuria measured with a dipstick test might be considered a potent risk factor for AF development.

Decreased Estimated Glomerular Filtration Rate (eGFR), Not Proteinuria, Is Associated with Asymptomatic Intracranial Arterial Stenosis in Chinese General Population

The relationship between chronic kidney disease (CKD), which is defined by declined estimated glomerular filtration rate (eGFR) and/or proteinuria, and asymptomatic intracranial arterial stenosis (ICAS) is largely unknown. We conducted a population-based, cross-sectional study by recruiting 5209 participants free of previous stroke, transient ischemic attack and coronary heart disease. eGFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula and proteinuria was estimated with urine dipstick. The presence of ICAS was assessed by transcranial color-coded Doppler (TCD). Out of the whole population, 684 (13.1%) participants suffered ICAS. After adjusting for the confounding factors, eGFR < 45 ml/min/m² was an independent risk factor of asymptomatic ICAS (odds ratio [OR], 3.29, 95% confidence interval [CI], 1.67–6.51), but the trend was different between the two groups stratified by the age of 60 (P = 0.01). However, the association between proteinuria and asymptomatic ICAS was not statistically significant. In conclusion, declined eGFR, not proteinuria, is associated with asymptomatic ICAS in Chinese general population, especially in people over 60 years old.

A Randomized, Open-Label Trial to Evaluate Switching to Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Alafenamide Plus Darunavir in Treatment-Experienced HIV-1-Infected Adults

Supplemental Digital Content is Available in the Text.

Background:

HIV-infected, treatment-experienced adults with a history of prior resistance and regimen failure can be virologically suppressed but may require multitablet regimens associated with lower adherence and potential resistance development.

Methods:

We enrolled HIV-infected, virologically suppressed adults with 2-class to 3-class drug resistance and at least 2 prior regimen failures into this phase 3, open-label, randomized study. The primary endpoint was the percentage of participants with HIV-1 RNA <50 copies per milliliter at week 24 [Food and Drug Administration (FDA) snapshot algorithm].

Results:

For 135 participants [elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) plus darunavir (DRV), n = 89; baseline regimen, n = 46], most of whom were taking a median of 5 tablets/d, simplification to E/C/F/TAF plus DRV was noninferior to continuation of baseline regimens at week 24 (plasma HIV-1 RNA <50 copies per milliliter: 96.6% vs. 91.3%, difference 5.3%, 95.001% CI: −3.4% to 17.4%). E/C/F/TAF plus DRV met prespecified criteria for noninferiority and superiority at week 48 for the same outcome. E/C/F/TAF plus DRV was well tolerated and had an improved renal safety profile compared with baseline regimens, with statistically significant differences between groups in quantitative total proteinuria and markers of proximal tubular proteinuria. Compared with baseline regimens, participants who switched to E/C/F/TAF plus DRV reported higher mean treatment satisfaction scale total scores and fewer days with missed doses.

Conclusions:

This study demonstrated that regimen simplification from a 5-tablet regimen to the 2-tablet, once-daily combination of E/C/F/TAF plus DRV has durable maintenance of virologic suppression and improvements in specific markers of renal safety. Such a strategy may lead to greater adherence and improved quality of life.

Effect of Kidney Dysfunction on Cerebral Cortical Thinning in Elderly Population

Chronic kidney disease has been linked to cognitive impairment and morphological brain change. However, less is known about the impact of kidney functions on cerebral cortical thickness. This study investigated the relationship between kidney functions and global or lobar cerebral cortical thickness (CTh) in 259 non-demented elderly persons. Forty-three participants (16.7%) had kidney dysfunction, which was defined as either a glomerular filtration rate (GFR) of <60 ml/min/1.73 m² or presence of proteinuria. Kidney dysfunction was associated with lower global (β = −0.05, 95% CI = −0.08 to −0.01) as well as frontal, parietal, temporal, occipital, and insular lobar CTh. In the stratified analysis, the associations were more pronounced in women, APOEε4 non-carriers, and participants with a lower cognitive score. Besides, kidney dysfunction significantly increased the risk of cortical thinning, defined as being the lowest CTh tertile, in the insular lobe (adjusted odds ratio = 2.74, 95% CI = 1.31−5.74). Our results suggested that kidney dysfunction should be closely monitored and managed in elderly population to prevent neurodegeneration.

Proteinuria in sarcoidosis: Prevalence and risk factors in a consecutive outpatient cohort

Introduction: While sarcoidosis has been recognized as a potential cause of proteinuria, no study has systematically evaluated the prevalence and risk factors for proteinuria in sarcoid patients. Methods: Consecutive sarcoid patients followed in a university clinic were identified prospectively. All patients with spot urine protein-to-creatinine ratio (UPCR) between 11-2012 and 07-2015 were included in the analysis. Proteinuria was defined as a spot UPCR equal to or exceeding 0.3 mg/mg. The primary goal of the study was to determine the prevalence of proteinuria in this sarcoidosis cohort. Results: Our study cohort consisted of 190 sarcoidosis patients (65% female, 82% white, mean age of 53 years (range 24-88)). Proteinuria was present in 14/190 (7%) of this cohort. Only5/190 patients (2.5%) had proteinuria who did not have a risk factor for proteinuria. Estimating the 24-hour urine protein excretion by extrapolating from the spot UPCR, proteinuria was moderate in amount (mean 1.60, range 0.32-5.06 mg/mg). Proteinuric patients received a lower mean daily dose of corticosteroids compared to those without proteinuria (0 mg vs 4.7 mg of prednisone); however, this difference did not reach statistical significance (p = 0.20). Conclusion: Our study found proteinuria in 7% of the 190 sarcoid patients. More than half of the patients with proteinuria had a known risk factor for proteinuria other than sarcoidosis. Proteinuria is uncommon in sarcoidosis, and, when it occurs, it should not be assumed that sarcoidosis is the cause without investigating alternative causes of proteinuria. (Sarcoidosis Vasc Diffuse Lung Dis 2017; 34: 142-148).

A red-NIR emissive probe for the selective detection of albumin in urine samples and live cells

A red-NIR fluorescence probe (TG-SA) has been designed, synthesised and its utility is demonstrated for staining human serum albumin (HSA) in gel electrophoresis, quantification of HSA in clinical urine samples and monitoring serum albumin homeostasis in live cells.

Prognostic value of urine dipstick proteinuria on mortality after acute ischemic stroke

BACKGROUND AND AIMS

Proteinuria is a marker of kidney disease and a strong risk factor for cardiovascular diseases including stroke. This study was aimed at investigating the prognostic value of proteinuria measured by urine dipstick in patients with acute ischemic stroke.

METHODS

This post-hoc analysis of a prospective cohort study included 3404 consecutive patients who had been admitted for acute ischemic stroke between November 2005 and June 2013. Proteinuria was defined as a trace or more of protein on a urine dipstick test routinely performed at admission. Date and cause of death until December 31, 2013 were collected. We investigated the association of proteinuria with all-cause mortality, cardiovascular mortality (defined as ICD-10 codes I00-I99), and non-cardiovascular mortality.

RESULTS

Proteinuria was present in 12.8% of the 3404 patients. During the mean follow-up period of 3.56 ± 2.22 years, there were 681 cases of all-cause mortality (460 cardiovascular deaths and 221 non-cardiovascular deaths). Multivariate Cox regression analysis showed that the presence of proteinuria was an independent risk factor for all-cause mortality (adjusted hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.40-2.04), cardiovascular mortality (adjusted HR 1.65, 95% CI 1.31-2.08), and non-cardiovascular mortality (adjusted HR 1.59, 95% CI 1.13-2.23). Adding proteinuria to the multivariate Cox models moderately improved the model performance for all-cause mortality (integrated area under curve [95% CI]: from 0.800 [0.784-0.816] to 0.803 [0.788-0.818], p = 0.026).

CONCLUSIONS

Proteinuria, which was detected on a urine dipstick test, was a significant predictor of mortality after acute ischemic stroke.

Progress and controversies in unraveling the glomerular filtration mechanism

PURPOSE OF REVIEW

At first sight, the glomerular filter appears like a problem that should be easily solved. The majority of researchers view the filter like an impermeable wall perforated by specialized and size-selective pores (pore model). However, the fact that this model is in conflict with many of the experimental findings suggests that it may not yet be complete.

RECENT FINDINGS

In the more recent electrokinetic model, we have proposed including electrical effects (streaming potentials). The present review investigates how this can provide a relatively simple mechanistic explanation for the great majority of the so far unexplained characteristics of the filter, for example why the filter never clogs.

SUMMARY

Understanding how the glomerular filter functions is a prerequisite to investigate the pathogenesis of proteinuric glomerular diseases and the link between glomerular proteinuria and cardiovascular disease.

Association of Estimated Glomerular Filtration Rate and Proteinuria With Lipid-Rich Plaque in Coronary Artery Disease

BACKGROUND

Estimated glomerular filtration rate (eGFR) and proteinuria are both important determinants of the risk of cardiovascular disease and mortality. The aim of the present study was to investigate the independent and combined effects of eGFR and proteinuria on tissue characterization of the coronary plaques of culprit lesions.

METHODS AND RESULTS

Conventional intravascular ultrasound and 3-D integrated backscatter intravascular ultrasound (IB-IVUS) were performed in 555 patients undergoing elective percutaneous coronary intervention. They were divided into 2 groups according to the absence or presence of proteinuria (dipstick result ≥1+). Patients with proteinuria had coronary plaque with significantly greater percentage lipid volume compared with those without (43.6±14.8% vs. 48.6±16.1%, P=0.005). Combined analysis was done using eGFR and absence or presence of proteinuria. Subjects with eGFR 45-59 ml/min/1.73 m2 and proteinuria were significantly more likely to have higher percent lipid volume compared with those with eGFR >60 ml/min/1.73 m2 without proteinuria. After multivariate adjustment for confounders, the presence of proteinuria proved to be an independent predictor for lipid-rich plaque (OR, 1.85; 95% CI: 1.12-3.06, P=0.016).

CONCLUSIONS

The addition of proteinuria to eGFR level may be of value in the risk stratification of patients with coronary artery disease.

Dendrin ablation prolongs life span by delaying kidney failure

Podocyte loss is central to the progression of proteinuric kidney diseases leading to end-stage kidney disease (ESKD), requiring renal replacement therapy, such as dialysis. Despite modern tools and techniques, the 5-year mortality of some patients requiring dialysis remains at about 70% to 80%. Thus, there is a great unmet need for podocyte-specific treatments aimed at preventing podocyte loss and the ensuing development of ESKD. Here, we show that ablation of the podocyte death-promoting protein dendrin delays the onset of ESKD, thereby expanding the life span of mice lacking the adapter protein CD2AP. Ablation of dendrin delays onset and severity of proteinuria and podocyte loss. In addition, dendrin ablation ameliorates mesangial volume expansion and up-regulation of mesangial fibronectin expression, which is mediated by a podocyte-secreted factor. In conclusion, onset of ESKD and death can be markedly delayed by blocking the function of dendrin.

Statins can improve proteinuria and glomerular filtration rate loss in chronic kidney disease patients, further reducing cardiovascular risk. Fact or fiction?

INTRODUCTION

The prevalence of chronic kidney disease (CKD), a risk factor for cardiovascular disease (CVD), is increasing worldwide. Statin treatment, the cornerstone of prevention or treatment of CVD, might have beneficial effects on urine protein excretion and renal function as determined by the glomerular filtration rate, whereas it might protect from acute kidney injury (AKI), mainly due to contrast-induced AKI. These beneficial effects on CKD may not be drug class effects; specific statins at specific doses may help prevent CKD deterioration and reduce CVD risk. We analysed all statin studies that had renal and CVD endpoints as main outcome measures. MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials were searched up to February 2015.

AREAS COVERED

We consider the effects of statins on microalbuminuria, proteinuria, glomerular filtration rate, AKI associated with angiography or percutaneous coronary intervention and on CVD event rates in patients with CKD.

EXPERT OPINION

Current evidence points towards the need to prescribe high-potency statins in patients with CKD, before a major decline in kidney function occurs. This may reduce CVD risk and delay the progress of CKD. Administration of either atorvastatin or rosuvastatin can prevent contrast-induced AKI before angiography or percutaneous coronary intervention. The combination of simvastatin + ezetimibe may decrease vascular events in patients with advanced CKD.

Long-Term Blood Pressure Variability, New-Onset Diabetes Mellitus, and New-Onset Chronic Kidney Disease in the Japanese General Population

Whether long-term blood pressure (BP) variability among individuals without diabetes mellitus is associated with new-onset chronic kidney disease (CKD) risk, independently of other BP parameters (eg, mean BP, cumulative exposure to BP) and metabolic profile changes during follow-up, remains uncertain. We used data from a nationwide study of 48 587 Japanese adults aged 40 to 74 years (mean age, 61.7 years; 39% men) without diabetes mellitus or CKD (estimated glomerular filtration rate <60 mL/min per 1.73 m2 or proteinuria by dipstick). BP was measured at baseline and during 3 annual follow-up visits (4 visits). BP variability was defined as standard deviation (SD) and average real variability during the 4 visits. At the year 3 follow-up visit, 6.3% of the population had developed CKD. In multivariable-adjusted logistic regression models, 1 SD increases in SDSBP (per 5 mmHg), SDDBP (per 3 mmHg), average real variabilitySBP (per 6 mmHg), and average real variabilityDBP (per 4 mmHg) were associated with new-onset CKD (odds ratios [ORs] and 95% confidence intervals, 1.15 [1.11-1.20], 1.08 [1.04-1.12], 1.13 [1.09-1.17], 1.06 [1.02-1.10], respectively; all P<0.01) after adjustment for clinical characteristics, and with mean BP from year 0 to year 3. The associations of SDBP and average real variabilityBP with CKD remained significant after additional adjustments for metabolic parameter changes during follow-up (ORs, 1.06-1.15; all P<0.01). Sensitivity analyses by sex, antihypertensive medication use, and the presence of hypertension showed similar conclusions. Among those in the middle-aged and elderly general population without diabetes mellitus, long-term BP variability during 3 years was associated with new-onset CKD risk, independently of mean or cumulative exposure to BP and metabolic profile changes during follow-up.

The effects of glucose-lowering therapies on diabetic kidney disease

Chronic hyperglycemia and its associated metabolic products are key factors responsible for the development and progression of diabetic chronic kidney disease (CKD). Endocrinologists are tasked with detection and management of early CKD before patients need referral to a nephrologist for advanced CKD or dialysis evaluation. Primary care physicians are increasingly becoming aware of the importance of managing hyperglycemia to prevent or delay progression of CKD. Glycemic control is an integral part of preventing or slowing the advancement of CKD in patients with diabetes; however, not all glucose-lowering agents are suitable for this patient population. The availability of the latest information on treatment options may enable physicians to thwart advancement of serious renal complication in patients suffering from diabetes. This review presents clinical data that shed light on the risk/benefit profiles of three relatively new antidiabetes drug classes, the dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 analogs, and sodium glucose co-transporter 2 inhibitors, particularly for patients with diabetic CKD, and summarizes the effects of these therapies on renal outcomes and glycemic control for endocrinologists and primary care physicians. Current recommendations for screening and diagnosis of CKD in patients with diabetes are also discussed.