Increasing Mortality in Adults With Diabetes and Low Estimated Glomerular Filtration Rate in the Absence of Albuminuria

The relationship between advanced glycation end products, metabolic metrics, HbA1c, and diabetic nephropathy

Background

In this cross-sectional study, we aim to investigate the value of non-invasive advanced glycation end products (AGEs) detection in the early screening of diabetic nephropathy(DN) among individuals with type 2 diabetes mellitus and assess whether metabolic parameters and glycated hemoglobin A1c (HbA1c) can moderate this relationship.

Methods

A total of 912 T2DM patients were enrolled. The urinary albumin-to-creatinine ratio (UACR) was measured in morning urine samples to assess DN. AGEs were non-invasively measured through skin autofluorescence. Recognizing the role of age in both AGEs and DN, AGEage was calculated as AGEs × age/100 for related analyses.

Results

The overall prevalence of DN in the present study was 37.2%. Elevated AGEage(χ2 = 61.06) was associated with a higher prevalence of DN. Multivariable linear regression demonstrated that AGEage was positively associated with UACR levels(β = 0.154, 95% CI: 0.126, 0.306, P<0.001). In the moderation analysis, glycated hemoglobin A1c (HbA1c) affected the correlation between AGEage and UACR. Body mass index (BMI) and triglyceride glucose-body mass index (TyG-BMI) also affect the correlation between AGEage and UACR, there were significant interactions between AGEage, HbA1c, BMI, TyG-BMI, and UACR.

Conclusions

Complex associations and interactions were observed between AGEs, metabolic metrics, HbA1c, and DN. Implementing comprehensive interventions can potentially benefit the prevention of DN in T2DM patients.

Lipidomics reveals potential biomarkers and pathophysiological insights in the progression of diabetic kidney disease

Background

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease, affecting over 30 % of diabetes mellitus (DM) patients. Early detection of DKD in DM patients can enable timely preventive therapies, and potentially delay disease progression. Since the kidney relies on fatty acid oxidation for energy, dysregulated lipid metabolism has been implicated in proximal tubular cell damage and DKD pathogenesis. This study aimed to identify lipid alterations during DKD development and potential biomarkers differentiating DKD from DM.

Methods

lipidomics analysis was performed on serum collected from 55 patients with DM, 21 with early DKD stage and 32 with advanced DKD, and 22 healthy subjects. Associations between lipids and DKD risk were evaluated by logistic regression.

Results

Lipid profiling revealed elevated levels of certain lysophosphatidylethanolamines (LPEs), phosphatidylethanolamines (PEs), ceramides (Cers), and diacylglycerols (DAGs) in the DM-DKD transition, while most LPEs, lysophosphatidylcholines (LPCs), along with several monoacylglycerol (MAG) and triacylglycerols (TAGs), increased further from DKD-E to DKD-A. Logistic regression indicated positive associations between LPCs, LPEs, PEs, and DAGs with DKD risk, with most LPEs correlating significantly with urinary albumin-to-creatinine ratio (UACR) and inversely with estimated glomerular filtration rate (eGFR). A machine-learning-derived biomarker panel, Lipid9, consisting of LPC(18:2), LPC(20:5), LPE (16:0), LPE (18:0), LPE (18:1), LPE (24:0), PE (34:1), PE (34:2), and PE (36:2), accurately distinguished DKD (AUC: 0.78, 95 % CI 0.68-0.86) from DM. Incorporating two clinical indexes, serum creatinine and blood urea nitrogen, the Lipid9-SCB model further improved DKD detection (AUC: 0.83, 95 % CI 0.75-0.90) from DM, and was notably more sensitive for identifying DKD-E (AUC: 0.79, 95 % CI 0.67-0.91).

Conclusion

This study deciphers the lipid signature in DKD progression, and suggests the Lipid9-SCB panel as a promising tool for early DKD detection in DM patients.

Association of Sleep Duration With Serum Estradiol Concentrations Among American Men and Women: Evidence From NHANES 2013-2016

Objective: To evaluate the association between sleep duration with serum estradiol concentrations and its variation by sex and age in American adults. Methods: Data were analyzed for 5406 men and women (≥ 20 years old) who participated in the cycles of the National Health and Nutrition Examination Survey 2013-2016, a cross-sectional study. Total estradiol (pg/mL) was measured and categorized (low, normal, and high) based on the NHANES protocol. Sleep duration was classified as ≤ 6, 6-9, and ≥ 9 h. Weighted multivariable adjusted and multinomial logistic regression models were conducted to assess these associations. Results: Our multivariable multinomial logistic regression analysis revealed no significant associations between sleep duration and serum estradiol concentrations among both American men and women. Specifically, comparisons of sleep durations (≤ 6 and ≥ 9 h) to the reference group (6-9 h) across various age categories showed odds ratios for low and high estradiol concentrations that remained statistically nonsignificant in fully adjusted models. These findings suggest that, unlike previous studies linking sleep duration with variations in other hormones, estradiol concentrations do not appear to be significantly affected by differences in sleep duration in either sex across all age groups studied. Conclusion: The lack of significant associations between sleep duration and serum estradiol concentrations indicates that sleep duration may not influence estradiol levels in the general population of American men and women. These results underscore the importance of continued research into how sleep influences hormonal balance. However, it is important to note that the NHANES data we used are from a cross-sectional study, which cannot establish a causal relationship between sleep duration and serum estradiol. Future studies should investigate additional factors, such as genetic predispositions, lifestyle habits, and environmental influences, that may modulate the relationship between sleep and hormone levels.

Conditional associations of sex steroid hormones with C-reactive protein levels in American children and adolescents: evidence from NHANES 2015-2016

Background

The relationship between sex steroid hormones and high-sensitivity C-reactive protein(hs-CRP) levels in American children and adolescents is understudied. This research will examine this association.

Methods

The study conducted a data analysis from the National Health and Nutrition Examination Survey (NHANES) 2015-2016, adjusting multiple linear regression models with R 4.2.2 and EmpowerStats. A total of 1,768 children and adolescents were surveyed. Data collection involved measurements of serum levels of testosterone, estradiol, sex hormone-binding globulin (SHBG) and hs-CRP.

Results

With the increase in testosterone, a brief rise (β=0.082, P=0.047) followed by an overall decline (β=-0.028, P=0.023) in hs-CRP was observed in the Male Prepubertal population, while a continuous decline (β=-0.002, P<0.05) was seen in the Male Pubertal group. A positive correlation (β=0.047, P<0.05) was found between testosterone and hs-CRP in the Female Prepubertal population, whereas no significant association (β=0.002, P>0.05) was detected in the Female Pubertal group. A significant inverse correlation was observed between estradiol and hs-CRP solely in the Female Pubertal group (β=-0.002, P<0.05), while no association was found in other populations. An inverse relationship between SHBG and hs-CRP was consistently noted across all groups: Male Prepubertal, Male Pubertal, Female Prepubertal, and Female Pubertal.

Conclusions

The association between sex steroid hormones and high-sensitivity C-reactive protein (hs-CRP) levels among American children and adolescents is conditional and influenced by multiple factors.

Associations between Waist Circumference and Sex Steroid Hormones in US Adult Men: Cross-Sectional Findings from the NHANES 2013-2016

Background

Obesity is recognized as a major public health issue worldwide, characterized by a growing prevalence among adult males. Several studies have identified an association between obesity and sex steroid hormone levels but only a few have considered the relationship between waist circumference (WC) and sex hormone levels in adult males. This study therefore aimed to evaluate the relationships between waist circumference (WC) and various sex steroid hormone levels in adult males in the United States.

Methods

This study analyzed data from 3,359 adult males aged 20 years and above, who participated in the National Health and Nutrition Examination Survey (NHANES) from 2013-2016 in the United States. We collected demographic data, including WC, and serum levels of testosterone, estradiol, SHBG, FAI, and T/E2 ratio. We adjusted the variables using multiple linear regression models with R 4.2.2 and EmpowerStats.

Results

After adjusting for confounders, WC was found to be negatively associated with testosterone (β = -0.117, P < 0.001) but positively correlated with estradiol (β = 0.002, P=0.002), especially beyond a WC of 104.5 cm (β = 0.004, P < 0.001). Underweight individuals showed a contrasting positive correlation between WC and testosterone (β = 0.351, P=0.016). WC was inversely related to SHBG, particularly when WC was ≤99.1 cm (β = -0.036, P < 0.001). The FAI initially increased and then decreased with WC, peaking at 98.6 cm. The T/E2 ratio negatively correlated with WC (β = -0.074, P < 0.001). These relationships varied among subgroups but remained unaffected by age or physical activity time.

Conclusions

Waist circumference is inversely correlated with testosterone, SHBG, and T/E2 ratio but positively correlated with estradiol, except for a positive correlation with testosterone in underweight males. Waist circumference serves as a crucial anthropometric measurement indicator for predicting sex steroid hormone levels in adult males.

Urinary non-albumin protein-creatinine ratio is an independent predictor of mortality in patients with type 2 diabetes: a retrospective cohort study

Albuminuria is a well-known predictor of chronic kidney disease in patients with type 2 diabetes mellitus (DM). However, proteinuria is associated with chronic complications in patients without albuminuria. In this retrospective cohort study, we explored whether non-albumin proteinuria is associated with all-cause mortality and compared the effects of non-albumin proteinuria on all-cause mortality between patients with and without albuminuria. We retrospectively collected data from patients with type 2 DM for whom we had obtained measurements of both urinary albumin-to-creatinine ratio (UACR) and urinary protein-to-creatinine ratio (UPCR) from the same spot urine specimen. Urinary non-albumin protein-creatinine ratio (UNAPCR) was defined as UPCR-UACR. Of the 1809 enrolled subjects, 695 (38.4%) patients died over a median follow-up of 6.4 years. The cohort was separated into four subgroups according to UACR (30 mg/g) and UNAPCR (120 mg/g) to examine whether these indices are associated with all-cause mortality. Compared with the low UACR and low UNAPCR subgroup as the reference group, multivariable Cox regression analyses indicated no significant difference in mortality in the high UACR and low UNAPCR subgroup (hazard ratio [HR] 1.189, 95% confidence interval [CI] 0.889-1.589, P = 0.243), but mortality risks were significantly higher in the low UACR and high UNAPCR subgroup (HR 2.204, 95% CI 1.448-3.356, P < 0.001) and in the high UACR with high UNAPCR subgroup (HR 1.796, 95% CI 1.451-2.221, P < 0.001). In the multivariable Cox regression model with inclusion of both UACR and UNAPCR, UNAPCR ≥ 120 mg/g was significantly associated with an increased mortality risk (HR 1.655, 95% CI 1.324-2.070, P < 0.001), but UACR ≥ 30 mg/g was not significantly associated with mortality risk (HR 1.046, 95% CI 0.820-1.334, P = 0.717). In conclusion, UNAPCR is an independent predictor of all-cause mortality in patients with type 2 DM.

Protective effect of paeoniflorin in diabetic nephropathy: A preclinical systematic review revealing the mechanism of action

BACKGROUND

Paeoniflorin (PF), the main active glucoside of Paeonia Lactiflora, has many pharmacological activities, such as inhibition of vasodilation, hypoglycemia, and immunomodulation. Although the current evidence has suggested the therapeutic effects of PF on diabetic nephropathy (DN), its potential mechanism of action is still unclear.

PURPOSE

A systematic review and meta-analysis of the existing literature on paeoniflorin treatment in DN animal models was performed to evaluate the efficacy and mechanism of PF in DN animal models.

METHODS

The risk of bias in each study was judged using the CAMARADES 10-item quality checklist with the number of criteria met varying from 4 / 10 to 7 / 10, with an average of 5.44. From inception to July 2022, We searched eight databases. We used the Cochrane Collaboration's 10-item checklist and RevMan 5.3 software to assess the risk of bias and analyze the data. Three-dimensional dose/time-effect analyses were conducted to examine the dosage/time-response relations between PF and DN.

RESULTS

Nine animal studies were systematically reviewed to evaluate the effectiveness of PF in improving animal models of DN. Meta-analysis data and intergroup comparisons indicated that PF slowed the index of mesangial expansion and tubulointerstitial injury, 24-h urinary protein excretion rate, expression of anti-inflammatory mediators (mRNA of MCP-1, TNF-α, iNOS, and IL-1 β), and expression of immune downstream factors (P-IRAK1, TIRF, P-IRF3, MyD88, and NF-κBp-p65). Furthermore, modeling methods, animal species, treatment duration, thickness of tissue sections during the experiment, and experimental procedures were subjected to subgroup analyses.

CONCLUSION

The present study demonstrated that the reno-protective effects of PF were associated with its inhibition on macrophage infiltration, reduction of inflammatory mediators, and immunomodulatory effects. In conclusion, PF can effectively slow down the progression of DN and hold promise as a protective drug for the treatment of DN. Due to the low bioavailability of PF, further studies on renal histology in animals are urgently needed. We therefore recommend an active exploration of the dose and therapeutic time frame of PF in the clinic and in animals. Moreover, it is suggested to actively explore methods to improve the bioavailability of PF to expand the application of PF in the clinic.

Circulating metabolites improve the prediction of renal impairment in patients with type 2 diabetes

INTRODUCTION

Low glomerular filtration rate (GFR) is a leading cause of reduced lifespan in type 2 diabetes. Unravelling biomarkers capable to identify high-risk patients can help tackle this burden. We investigated the association between 188 serum metabolites and kidney function in type 2 diabetes and then whether the associated metabolites improve two established clinical models for predicting GFR decline in these patients.

RESEARCH DESIGN AND METHODS

Two cohorts comprising 849 individuals with type 2 diabetes (discovery and validation samples) and a follow-up study of 575 patients with estimated GFR (eGFR) decline were analyzed.

RESULTS

Ten metabolites were independently associated with low eGFR in the discovery sample, with nine of them being confirmed also in the validation sample (ORs range 1.3-2.4 per 1SD, p values range 1.9×10-2-2.5×10-9). Of these, five metabolites were also associated with eGFR decline (ie, tiglylcarnitine, decadienylcarnitine, total dimethylarginine, decenoylcarnitine and kynurenine) (β range -0.11 to -0.19, p values range 4.8×10-2 to 3.0×10-3). Indeed, tiglylcarnitine and kynurenine, which captured all the information of the other three markers, improved discrimination and reclassification (all p<0.01) of two clinical prediction models of GFR decline in people with diabetes.

CONCLUSIONS

Further studies are needed to validate our findings in larger cohorts of different clinical, environmental and genetic background.

Mitochondrial DNA Changes in Blood and Urine Display a Specific Signature in Relation to Inflammation in Normoalbuminuric Diabetic Kidney Disease in Type 2 Diabetes Mellitus Patients

Mitochondrial dysfunction is an important mechanism contributing to the development and progression of diabetic kidney disease (DKD). Mitochondrial DNA (mtDNA) levels in blood and urine were evaluated in relation to podocyte injury and proximal tubule (PT) dysfunction, as well as to a specific inflammatory response in normoalbuminuric DKD. A total of 150 type 2 diabetes mellitus (DM) patients (52 normoalbuminuric, 48 microalbuminuric, and 50 macroalbuminuric ones, respectively) and 30 healthy controls were assessed concerning the urinary albumin/creatinine ratio (UACR), biomarkers of podocyte damage (synaptopodin and podocalyxin), PT dysfunction (kidney injury molecule-1 (KIM-1) and N-acetyl-β-(D)-glucosaminidase (NAG)), and inflammation (serum and urinary interleukins (IL-17A, IL-18, and IL-10)). MtDNA-CN and nuclear DNA (nDNA) were quantified in peripheral blood and urine via qRT-PCR. MtDNA-CN was defined as the ratio of the number of mtDNA/nDNA copies via analysis of the CYTB/B2M and ND2/B2M ratio. Multivariable regression analysis provided models in which serum mtDNA directly correlated with IL-10 and indirectly correlated with UACR, IL-17A, and KIM-1 (R² = 0.626; p < 0.0001). Urinary mtDNA directly correlated with UACR, podocalyxin, IL-18, and NAG, and negatively correlated with eGFR and IL-10 (R² = 0.631; p < 0.0001). Mitochondrial DNA changes in serum and urine display a specific signature in relation to inflammation both at the podocyte and tubular levels in normoalbuminuric type 2 DM patients.

Clinical outcomes in patients with type 2 diabetes mellitus-related kidney disease: A Jordanian population cohort study

BACKGROUND

Diabetic kidney disease (DKD) increases the risk of cardiovascular (CV) complications, kidney disease progression, and mortality. We aimed to determine the incidence and risk of these outcomes according to DKD phenotype among the Jordanian population.

METHODS

A total of 1172 type 2 diabetes mellitus patients with estimated glomerular filtration rates (eGFRs) of >30 ml/min/1.73 m² were followed-up from 2019 to 2022. At baseline, patients were classified according to the presence of albuminuria (>30 mg/g creatinine) and reduced eGFR (<60 ml/min/1.73 m²) into four phenotypes: non-DKD (reference category), albuminuric DKD without decreased eGFR, non-albuminuric DKD with decreased eGFR, and albuminuric DKD with decreased eGFR.

RESULTS

Mean follow-up was 2.9 ± 0.4 years. Overall, 147 patients (12.5 %) experienced CV events, while 61 (5.2 %) demonstrated kidney disease progression (eGFR: <30 ml/min/1.73 m²). The mortality rate was 4.0 %. Multivariable-adjusted risk for CV events and mortality was greatest for the albuminuric DKD with decreased eGFR group (hazard ratio [HR]: 1.45, 95 % confidence interval [CI]: 1.02-2.33 and HR: 6.36, 95 % CI: 2.98-13.59, respectively), with the risk increasing when adjusted for prior CV history (HR: 1.47, 95 % CI: 1.06-3.42 and HR: 6.70, 95 % CI: 2.70-16.60, respectively). Risk of a ≥40 % decline in eGFR was greatest for the albuminuric DKD with decreased eGFR group (HR: 3.45, 95 % CI: 1.74-6.85), followed by the albuminuric DKD without decreased eGFR group (HR: 1.6, 95 % CI: 1.06-2.75).

CONCLUSION

Thus, patients with albuminuric DKD and decreased eGFR were at greater risk for poor CV, renal, and mortality outcomes compared to other phenotypes.

Risk of cardiovascular disease, death, and renal progression in diabetes according to albuminuria and estimated glomerular filtration rate

AIM

We aimed to examine risks of major cardiovascular events (MACEs), renal outcomes, and all-cause mortality in type 2 diabetes mellitus (T2DM) patients with different diabetic kidney disease (DKD) subtypes.

METHODS

A total of 36,509 participants with T2DM recruited from 20 community sites across mainland China were followed up during 2011-2016. DKD subtypes were categorized based on albuminuria (urinary albumin-to-creatinine ratio, UACR ≥ 30 mg/g) and reduced estimated glomerular filtration rate (eGFR < 60 ml/min/1.73 m²) as Alb^-/eGFR^-, Alb⁺/eGFR^-, Alb^-/eGFR⁺, and Alb⁺/eGFR⁺. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs) of developing clinical outcomes in DKD subtypes.

RESULTS

More than half (53.5%) of participants with diabetes and reduced eGFR had normal UACR levels (Alb^-/eGFR⁺), termed as non-albuminuria DKD. These patients had a modest increase in the risks of MACEs (hazard ratio, HR 1.42 [95% CI 1.08;1.88]) and mortality (HR 1.42 [1.04;1.92]) compared with patients without DKD, whereas CKD progression was not significantly increased (HR 0.97 [0.60;1.57]). Participants with albuminuria (Alb⁺/eGFR^- or Alb⁺/eGFR⁺) had higher risks of clinical outcomes. Subgroup analysis revealed that the associations between non-albuminuria DKD and risks of MACEs and mortality were more evident in those aged <65 years.

CONCLUSION

Non-albuminuria DKD accounts for more than half of DKD cases with low eGFR in Chinese diabetes patients. Diabetes patients with albuminuria are at higher risks of developing clinical outcomes and warrant early intervention, as well as patients with non-albuminuria DKD with age < 65 years.

Efficacy of traditional Chinese medicine injection for diabetic kidney disease: A network meta analysis and systematic review

Background: Diabetic kidney disease (DKD) is an important public health problem worldwide that increases the mortality of patients and incurs high medical costs. Traditional Chinese Medicine injections (TCMIs) are widely used in clinical practice. However, their efficacy is unknown owing to a lack of definitive evidence. This study conducted a network meta-analysis (NMA) to evaluate the efficacy and safety of traditional Chinese medicine injections in the treatment of DKD to provide a reference for clinical treatment. Methods: Total 7 databases had been searched, which included PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), Chinese scientific journal database (VIP), WanFang, and SinoMed. Only randomised controlled trials (RCT) had been included for analysis. The retrieval time limit was from the establishment of the database until 20 July 2022. Cochrane Risk of Bias 2.0 tool was used to evaluate the quality of the studies. Network meta-analyses, and Trial Sequential Analyses (TSA) were used to analysis the effectiveness of the included RCTs for DKD. The Stata 15.1 and R 4.0.4 were used to perform the network meta-analysis. Sensitivity analysis was used to assess the robustness of the findings. The effect of the intervention evidence are summarized on the basis of the minimum background framework. Results: NMA showed that the total effective rate of SMI, DCI, DHI, HQI, and SKI combined with alprostadil injection (PGE1) was better than PGE1 single used. Based on the surface under the cumulative ranking curve values, PGE1+DHI was the most effective for urinary albumin excretion rate and 24 h urinary albumin, PGE1+HQI was the most effective for the total response rate and β2-MG, and PGE1+SKI was the most effective for serum creatinine and blood urea nitrogen. Cluster analysis found that PGE1+HQI and PGE1+SKI could be the best treatments in terms of primary outcome measures. PGE1+SKI was found to be most effective on glomerular filtration function. PGE1+DHI was most effective for urinary protein-related indices. Conclusion: The efficacy of TCMI combined with PGE1 was higher than PGE1 single used. PGE1+HQI and PGE1+SKI were the most effective treatments. The safety of TCMI treatment should be investigated further. This study needs to be validated using large-sample, double-blind, multicentre RCTs. Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=348333], identifier [CRD42022348333].

CVD risk in non-albuminuric chronic kidney disease in hypertensive, non-diabetic subjects: A post-hoc analysis from SPRINT

Introduction

The risks associated with non-albuminuric chronic kidney disease (CKD) have been investigated in diabetes mellitus but not in hypertensive patients. The objective of this study was to investigate the risks associated with non-albuminuric CKD in treated hypertensive patients in the Systolic Blood Pressure Intervention Trial (SPRINT) population.

Methods

Based on baseline albuminuria status (urine albumin/creatinine ratio [UACR], ≥30 or <30 mg/g) and the levels of estimated glomerular filtration rate ([eGFR], ≥60, 45-59, or <45 mL/min/1.73 m²), participants were classified into six subgroups to assess the risks associated with the primary outcome and mortality. The primary composite outcome was myocardial infarction, other acute coronary syndromes, stroke, heart failure, or mortality from cardiovascular causes.

Results

During a median follow-up of 3.26 years in 8,866 hypertensive patients, there were 352 deaths and 547 participants with the primary outcome. In adjusted Cox regression analysis using non-CKD and non-albuminuria (eGFR ≥60 mL/min/1.73 m² combined with UACR <30 mg/g) as reference, albuminuria whether combined with CKD or not, showed significantly higher risk of both primary outcome and all-cause mortality in the total population. Whereas, non-albuminuria only combined with eGFR <45 mL/min/1.73 m² showed significantly higher risk of both primary outcome and all-cause mortality in the intensive-therapy group.

Discussion

Non-albuminuric CKD did have higher risk of all-cause and CVD mortality only if the eGFR <45 mL/min/1.73 m². Increased albuminuria conferred higher risk of primary outcome and all-cause mortality irrespective the levels of eGFR.

Clinical trial registration

ClinicalTrials.gov, number: NCT01206062.

Synergistic effect of chronic kidney disease, neuropathy, and retinopathy on all-cause mortality in type 1 and type 2 diabetes: a 21-year longitudinal study

Background

The prognostic value of common and frequently associated diabetic microvascular complications (MVC), namely chronic kidney disease (CKD), cardiac autonomic neuropathy (CAN), peripheral neuropathy (DPN), and retinopathy (DR), is well established. However, the impact of their different combinations on long-term mortality has not been adequately assessed.

Methods

We retrospectively analyzed 21-year longitudinal data from 303 patients with long-standing type 1 (T1D) or type 2 diabetes (T2D), who were thoroughly characterized at baseline for the presence of MVC using 99mTc-DTPA dynamic renal scintigraphy, overnight urine collection, cardiovascular autonomic tests, monofilament testing, and dilated fundus oculi examination.

Results

After a 5,244 person-years follow-up, a total of 133 (43.9%) deaths occurred. The presence of CKD and CAN, regardless of other MVC, increased the adjusted all-cause mortality risk by 117% (HR 2.17 [1.45–3.26]) and 54% (HR 1.54 [1.01–2.36]), respectively. Concomitant CKD&CAN at baseline were associated with the highest mortality risk (HR 5.08 [2.52–10.26]), followed by CKD&DR (HR 2.95 [1.63–5.32]), and CAN&DR (HR 2.07 [1.11–3.85]). Compared with patients free from MVC, the mortality risk was only numerically higher in those with any isolated MVC (HR 1.52 [0.87–2.67]), while increased by 203% (HR 3.03 [1.62–5.68]) and 692% (HR 7.92 [2.93–21.37]) in patients with two and three concomitant MVC, respectively.

Conclusions

Our study demonstrates the long-term, synergistic, negative effects of single and concomitant diabetic MVC on all-cause mortality, which should encourage comprehensive screenings for MCV in both T1D and T2D to improve risk stratification and treatment.

Analysis of the Renal Protection and Antioxidative Stress Effects of Panax notoginseng Saponins in Diabetic Nephropathy Mice

Objective

Diabetic nephropathy (DN), a diabetes-induced chronic complication, is the major trigger of end-stage renal disease. As the main active ingredient of Panax notoginseng (PNG), Panax notoginseng saponins (PNS) are crucial in treating renal diseases. This study is aimed at investigating the role played by PNS in renal protection and antioxidative stress (OS) in DN mice.

Methods

A DN mouse model was constructed, and then low, medium, and high doses of PNS were used to intervene the model group mice. Eight weeks after intervention, the 24 h urine protein (UPro) and urinary albumin (UAlb) were quantitatively examined, and the related blood biochemical indices were measured. HE and PAS staining were performed for pathological changes of renal tissue. ELISA and western blotting were carried out to quantify the levels of OS indexes and inflammatory factors (IFs) in mouse kidney tissues and the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1), respectively.

Results

The weight of DN mice decreased first compared with control animals and then gradually increased after different doses of PNS treatment. Besides, DN mice presented elevated urine volume, UPro, and UAlb, all of which were reversed by PNS intervention. SOD activity and GSH content in renal tissues of the model group mice decreased markedly versus the control group, and MDA, CRP, IL-6, and TGF-β1 contents elevated statistically, while different doses of PNS effectively reduced the OS injury and IFs in mice. Compared with the model group, PNS dose-dependently increased Nrf2 and HO-1 levels in DN mice.

Conclusions

PNS is protective of HFF + STZ-induced DN mice against kidney tissue damage and can reduce the excretion of UPro and relieve the OS state of mice, possibly by activating Nrf2/HO-1 axis to play an antioxidant and anti-inflammatory role.

Nonalbuminuric Diabetic Kidney Disease and Risk of All-Cause Mortality and Cardiovascular and Kidney Outcomes in Type 2 Diabetes: Findings From the Hong Kong Diabetes Biobank

RATIONALE & OBJECTIVE

Nonalbuminuric diabetic kidney disease (DKD) has become the prevailing DKD phenotype. We compared the risks of adverse outcomes among patients with this phenotype compared with other DKD phenotypes.

STUDY DESIGN

Multicenter prospective cohort study.

SETTINGS & PARTICIPANTS

19,025 Chinese adults with type 2 diabetes enrolled in the Hong Kong Diabetes Biobank.

EXPOSURES

DKD phenotypes defined by baseline estimated glomerular filtration rate (eGFR) and albuminuria: no DKD (no decreased eGFR or albuminuria), albuminuria without decreased eGFR, decreased eGFR without albuminuria, and albuminuria with decreased eGFR.

OUTCOMES

All-cause mortality, cardiovascular disease (CVD) events, hospitalization for heart failure (HF), and chronic kidney disease (CKD) progression (incident kidney failure or sustained eGFR reduction ≥40%).

ANALYTICAL APPROACH

Multivariable Cox proportional or cause-specific hazards models to estimate the relative risks of death, CVD, hospitalization for HF, and CKD progression. Multiple imputation was used for missing covariates.

RESULTS

Mean participant age was 61.1 years, 58.3% were male, and mean diabetes duration was 11.1 years. During 54,260 person-years of follow-up, 438 deaths, 1,076 CVD events, 298 hospitalizations for HF, and 1,161 episodes of CKD progression occurred. Compared with the no-DKD subgroup, the subgroup with decreased eGFR without albuminuria had higher risks of all-cause mortality (hazard ratio [HR], 1.59 [95% CI, 1.04-2.44]), hospitalization for HF (HR, 3.08 [95% CI, 1.82-5.21]), and CKD progression (HR, 2.37 [95% CI, 1.63-3.43]), but the risk of CVD was not significantly greater (HR, 1.14 [95% CI, 0.88-1.48]). The risks of death, CVD, hospitalization for HF, and CKD progression were higher in the setting of albuminuria with or without decreased eGFR. A sensitivity analysis that excluded participants with baseline eGFR <30 mL/min/1.73 m² yielded similar findings.

LIMITATIONS

Potential misclassification because of drug use.

CONCLUSIONS

Nonalbuminuric DKD was associated with higher risks of hospitalization for HF and of CKD progression than no DKD, regardless of baseline eGFR.

Cobalamin Intake and Related Biomarkers: Examining Associations With Mortality Risk Among Adults With Type 2 Diabetes in NHANES

OBJECTIVE

Despite that periodical monitoring of cobalamin (vitamin B12) in metformin-treated patients with diabetes is recommended, cobalamin-associated mortality benefits or risks remain unclear. We investigated the association between cobalamin intake and related biomarkers and mortality risk in adults with diabetes using metformin or not.

RESEARCH DESIGN AND METHODS

This study included 3,277 adults with type 2 diabetes from the National Health and Nutrition Examination Survey (NHANES) and followed up until 31 December 2015. Weighted Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% CIs for mortality risk.

RESULTS

Among 3,277 participants, 865 all-cause deaths occurred during a median follow-up of 7.02 years. There was no robust relationship between all-cause mortality and serum cobalamin or intake of foods or cobalamin supplements, regardless of metformin treatment (each P ≥ 0.120). The doubling of methylmalonic acid (MMA), a cobalamin-deficiency marker, was significantly associated with higher all-cause (HR 1.31 [95% CI 1.18-1.45], P < 0.001) and cardiac (HR 1.38 [95% CI 1.14-1.67], P = 0.001) mortality. Cobalamin sensitivity was assessed by the combination of binary B12low/high and MMAlow/high (cutoff values: cobalamin 400 pg/mL, MMA 250 nmol/L). Patients with decreased cobalamin sensitivity (MMAhighB12high) had the highest mortality risk. The multivariable-adjusted HRs (95% CIs) of all-cause mortality in MMAlowB12low, MMAlowB12high, MMAhighB12low, and MMAhighB12high groups were 1.00 (reference), 0.98 (0.75-1.28), 1.49 (1.16-1.92), and 1.96 (1.38-2.78), respectively. That association was especially significant in metformin nonusers.

CONCLUSIONS

Serum and dietary cobalamin were not associated with reduced mortality. Decreased cobalamin sensitivity was significantly associated with all-cause and cardiac mortality, particularly among metformin nonusers.

COULD PROTEINURIA PREDICT THE RENAL PROGNOSES OF PATIENTS WITH TYPE 2 DIABETES MELLITUS AND DIABETIC NEPHROPATHY?

AIMS

This study investigated the relationship between proteinuria levels, clinicopathological features, and renal prognoses in Chinese patients with type 2 diabetes mellitus (T2DM) and diabetic nephropathy (DN).

METHODS

Three hundred patients with T2DM and biopsy-proven DN were enrolled. Patients were stratified by 24-h proteinuria levels: Group 1:≤1g/24h); Group 2:1-3g/24h; and Group 3:≥3g/24h. Renal outcomes were defined as having reached end-stage renal disease (ESRD). The proteinuria level's influence on the renal outcomes was evaluated using Cox regression analysis.

RESULTS

Among subgroups stratified by proteinuria levels, systolic blood pressure, serum creatinine, BUN, cholesterol, DR and hypertension incidence, the incidences of patients who progressed to ESRD were the lowest in group 1 (P<0.05). However, eGFR, serum albumin and hemoglobin were highest in group 1. Patients with higher proteinuria levels had much lower five-year renal survival rates. Univariate analyses revealed that higher proteinuria levels were significant clinical predictors of renal prognosis (P<0.05), although they were not independent risk factors for progression to ESRD in the multivariate Cox proportional hazard analysis (P>0.05).

CONCLUSIONS

The higher the level of proteinuria, the lower the 5-year renal survival rate of DN patients, but there was no significant correlation between proteinuria level and 5-year renal survival rate. Other factors in the proteinuria group may have more significant effects on the 5-year renal survival rate, such as lower baseline eGFR, serum albumin, hemoglobin and higher cholesterol, higher incidences of DR and more severe lesions.

Predictive Risk Models to Identify Patients at High-Risk for Severe Clinical Outcomes With Chronic Kidney Disease and Type 2 Diabetes

Introduction/Objective:

Predictive risk models identifying patients at high risk for specific outcomes may provide valuable insights to providers and payers regarding points of intervention and modifiable factors. The goal of our study was to build predictive risk models to identify patients with chronic kidney disease (CKD) and type 2 diabetes (T2D) at high risk for progression to end stage kidney disease (ESKD), mortality, and hospitalization for cardiovascular disease (CVD), cerebrovascular disease (CeVD), and heart failure (HF).

Methods:

This was a retrospective observational cohort study utilizing administrative claims data in patients with CKD (stage 3-4) and T2D aged 65 to 89 years enrolled in a Medicare Advantage Drug Prescription plan offered by Humana Inc. between 1/1/2012 and 12/31/2017. Patients were enrolled ≥1 year pre-index and followed for outcomes, including hospitalization for CVD, CeVD and HF, ESKD, and mortality, 2 years post-index. Pre-index characteristics comprising demographic, comorbidities, laboratory values, and treatment (T2D and cardiovascular) were evaluated and included in the models. LASSO technique was used to identify predictors to be retained in the final models followed by logistic regression to generate parameter estimates and model performance statistics. Inverse probability censoring weighting was used to account for varying follow-up time.

Results:

We identified 169 876 patients for inclusion. Declining estimated glomerular filtration rate (eGFR) increased the risk of hospitalization for CVD (38.6%-61.8%) and HF (2-3 times) for patients with eGFR 15 to 29 mL/min/1.73 m² compared to patients with eGFR 50 to 59 mL/min/1.73 m². Patients with urine albumin-to-creatinine ratio (UACR) ≥300 mg/g had greater chance for hospitalization for CVD (2.0 times) and HF (4.9 times), progression to ESKD (2.9 times) and all-cause mortality (2.4 times) than patients with UACR <30 mg/g. Elevated hemoglobin A1c (≥8%) increased the chances for hospitalization for CVD (21.3%), CeVD (45.4%), and death (20.6%). Among comorbidities, history of HF increased the risk for ESKD, mortality, and hospitalization for CVD, CeVD, and HF.

Conclusions:

The predictive models developed in this study could potentially be used as decision support tools for physicians and payers, and the risk scores from these models can be applied to future outcomes studies focused on patients with T2D and CKD.

Update on pathogenesis and diagnosis flow of normoalbuminuric diabetes with renal insufficiency

In recent decades, the prevalence of diabetic kidney disease has remained stable and appears to be a wide heterogeneity. Normoalbuminuric diabetes with renal insufficiency, which is characterized by a decline in the glomerular filtration rate in the absence of albuminuria, has been identified as an albuminuria-independent phenotype of diabetic kidney disease. Epidemiological data demonstrate that normoalbuminuric phenotype is prevalent. Compared to albuminuric phenotype, normoalbuminuric phenotype has distinct clinical characteristics and a wide heterogeneity of pathological features. Currently, the pathogenesis of normoalbuminuric phenotype remains unclear. Additionally, the flow of diagnosing normoalbuminuric phenotype is not perfect. In this article, we review the latest studies addressing the epidemiology, clinical characteristics, and pathology of normoalbuminuric phenotype. Based on the studies of clinical features and renal histopathologic changes, we attempt to propose an underlying pathogenesis model and a flow chart for diagnosing normoalbuminuric phenotype.

Lipidomics Reveals Serum Specific Lipid Alterations in Diabetic Nephropathy

In diabetes mellitus (DM), disorders of glucose and lipid metabolism are significant causes of the onset and progression of diabetic nephropathy (DN). However, the exact roles of specific lipid molecules in the pathogenesis of DN remain unclear. This study recruited 577 participants, including healthy controls (HCs), type-2 DM (2-DM) patients, and DN patients, from the clinic. Serum samples were collected under fasting conditions. Liquid chromatography-mass spectrometry-based lipidomics methods were used to explore the lipid changes in the serum and identify potential lipid biomarkers for the diagnosis of DN. Lipidomics revealed that the combination of lysophosphatidylethanolamine (LPE) (16:0) and triacylglycerol (TAG) 54:2-FA18:1 was a biomarker panel for predicting DN. The receiver operating characteristic analysis showed that the panel had a sensitivity of 89.1% and 73.4% with a specificity of 88.1% and 76.7% for discriminating patients with DN from HCs and 2-DM patients. Then, we divided the DN patients in the validation cohort into microalbuminuria (diabetic nephropathy at an early stage, DNE) and macroalbuminuria (diabetic nephropathy at an advanced stage, DNA) groups and found that LPE(16:0), phosphatidylethanolamine (PE) (16:0/20:2), and TAG54:2-FA18:1 were tightly associated with the stages of DN. The sensitivity of the biomarker panel to distinguish between patients with DNE and 2-DM, DNA, and DNE patients was 65.6% and 85.9%, and the specificity was 76.7% and 75.0%, respectively. Our experiment showed that the combination of LPE(16:0), PE(16:0/20:2), and TAG54:2-FA18:1 exhibits excellent performance in the diagnosis of DN.

Renal function and attributable risk of death and cardiovascular hospitalization in participants with diabetes from a registry-based cohort

AIMS

To estimate the attributable risk of renal function on all-cause mortality and cardiovascular hospitalization in patients with diabetes.

METHODS

A prospective cohort study in 19,469 adults with diabetes, free of cardiovascular disease, attending primary care in Spain (2008-2011). The estimated glomerular filtration rate (eGFR) and other variables were collected and patients were followed to the first hospitalization for coronary or stroke event, or death, until the end of 2012. The cumulative incidence of the study endpoints by eGFR categories was graphically displayed and adjusted population attributable risks (PARs) for low eGFR was calculated.

RESULTS

Mean follow-up was 3.2 years and 506 deaths and 1720 hospitalizations were recorded. The cumulative risk for the individual events increased as eGFR levels decreased. The PAR associated with having an eGFR of 60mL/min/1.73m² or less was 11.4% (95% CI 4.8-18.3) for all-cause mortality, 9.2% (95% CI 5.3-13.4) for coronary heart disease, and 2.6% (95% CI -1.8 to 7.4) for stroke.

CONCLUSIONS

Reduced eGFR levels were associated with a larger proportion of avoidable deaths and cardiovascular hospitalizations in people with diabetes compared to previously reported results in people with other cardiovascular risk factors.

Clinical and Pathological Characteristics of Patients With Nonproteinuric Diabetic Nephropathy

INTRODUCTION

As the most common complication of diabetes mellitus (DM), diabetic nephropathy (DN) was initially considered to begin with proteinuria preceding the progression of renal insufficiency. This clinical paradigm has been questioned in the late decades, as many DM patients without proteinuria have progressive renal insufficiency. However, the characteristics of nonproteinuric DN were not fully clear yet.

PATIENTS AND METHODS

A total of 390 patients with renal biopsy-proven DN in our center were retrospectively recruited in the current study. Clinical and histopathological data of the patients were analyzed. We used propensity score-matching methods to address the imbalance of age, sex, and diabetes duration for comparative analyses.

RESULTS

Among all the renal biopsy-proven DN patients with renal biopsy proven DN, 18 patients were classified as nonproteinuric DN. Compared with 36 propensity score-matched proteinuric DN patients, diabetic retinopathy (DR) was less frequent in nonproteinuric DN patients (38.9% vs. 66.4%, p<0.05). During the follow-up of 24.0 (12.0-42.0) months, the probability of developing the end-stage renal disease (ESRD) was significantly lower in nonproteinuric DN patients than in proteinuric ones in both the propensity score-matched cohort and overall cohort (log-rank test, p<0.001 and p<0.001, respectively).

CONCLUSIONS

Compared with proteinuric DN patients, DR was less frequent in nonproteinuric DN patients. Nonproteinuric DN patients had better renal outcomes than proteinuric DN patients.

Panax notoginseng preparations as adjuvant therapy for diabetic kidney disease: a systematic review and meta-analysis

Context: Panax notoginseng (Burk.) F.H. Chen (Araliaceae) preparations (PNP) are traditional Chinese medicines used as adjuvant therapeutics for diabetic kidney disease (DKD).Objective: To systematically review the efficacy of PNP as adjunct DKD therapy, including their effects on kidney function, serum lipid levels and fasting blood glucose levels.Methods: The databases PubMed, Embase, Medline, Cochrane Library, CINAHL, China Biology Medicine disc, Wanfang, VIP and China National Knowledge Infrastructure were systematically searched from the date of their inception until May 2019. Panax notoginseng, Panax notoginseng saponins, Lulutong, Xueshuantong and Xuesaitong were the key terms searched. Randomized controlled trials (RCTs) comparing the combined use of PNP and conventional medicines (CM) versus CM for DKD were included. Data were pooled using random or fixed effect models depending on heterogeneity.Results: In total, 24 RCTs involving 1918 participants were analysed. Adjunct PNP with CM was associated with reduction of albuminuria (MD -26.89 mg, 95% CI: -33.35 to -20.42), proteinuria (MD -0.32 g/24 h, 95% CI: -0.36 to -0.27), serum creatinine (MD -4.52 μmol/L, 95% CI: -8.71 to -0.32), total cholesterol (MD -1.56 mmol/L, 95% CI: -2.33 to -0.78), triglycerides (TG) (MD -0.56 mmol/L, 95% CI: -0.80 to -0.31) and low-density lipoprotein cholesterol (MD -0.94 mmol/L, 95% CI: -1.49 to -0.40) compared with CM.Conclusions: This is the first meta-analysis investigating adjuvant PNP therapy for DKD. PNP apparently exerted beneficial effects on kidney function and improved the metabolism of serum lipids by CM. Further, well-conducted, high-quality trials on DKD patients are needed to provide high-quality evidence.

Biomarkers in Progressive Chronic Kidney Disease. Still a Long Way to Go

The traditional chronic kidney disease (CKD) biomarkers (eGFR based on serum creatinine, sex and age and albuminuria) cannot predict a patient's individual risk for developing progressive CKD. For this reason, it is necessary to identify novel CKD biomarkers that will be able to predict which patients are prone to develop progressive disease and discriminate between disease processes in different parts of the nephron (glomeruli or tubules). A good biomarker should change before or simultaneously with lesion development and its changes should correlate strongly with lesion development. Also, there should be a close relationship between severity of injury and amount of detectable biomarker and its levels should decrease with diminishing injury. Among the large number of molecules under investigation, we have reviewed the most promising ones: NGAL and KIM-1, MCP-1, MMP-9, clusterin, MMP-9, TIMP-1, Procollagen I alpha 1 and suPAR. All these, have been studied as biomarkers for prediction of CKD progression in cohorts of patients with chronic kidney disease of different stages and various aetiologies (proteinuric and non-proteinuric, glomerulonephritides, diabetic, hypertensive and polycystic kidney disease). There is evidence that these molecules could be useful as biomarkers for progressive chronic kidney disease, however, the available data are not enough to draw final conclusions. Further studies with large cohorts and long follow-up are required to identify appropriate biomarkers, that will be able to accurately and reliably define the risk for progressive chronic kidney disease.

Empagliflozin and Cardiovascular and Kidney Outcomes across KDIGO Risk Categories: Post Hoc Analysis of a Randomized, Double-Blind, Placebo-Controlled, Multinational Trial

BACKGROUND AND OBJECTIVES

In the Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients (EMPA-REG Outcome), empagliflozin, in addition to standard of care, significantly reduced risk of cardiovascular death by 38%, hospitalization for heart failure by 35%, and incident or worsening nephropathy by 39% compared with placebo in patients with type 2 diabetes and established cardiovascular disease. Using EMPA-REG Outcome data, we assessed whether the Kidney Disease Improving Global Outcomes (KDIGO) CKD classification had an influence on the treatment effect of empagliflozin.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Patients with type 2 diabetes, established atherosclerotic cardiovascular disease, and eGFR≥30 ml/min per 1.73 m² at screening were randomized to receive empagliflozin 10 mg, empagliflozin 25 mg, or placebo once daily in addition to standard of care. Post hoc, we analyzed cardiovascular and kidney outcomes, and safety, using the two-dimensional KDIGO classification framework.

RESULTS

Of 6952 patients with baseline eGFR and urinary albumin-creatinine ratio values, 47%, 29%, 15%, and 8% were classified into low, moderately increased, high, and very high KDIGO risk categories, respectively. Empagliflozin showed consistent risk reductions across KDIGO categories for cardiovascular outcomes (P values for treatment by subgroup interactions ranged from 0.26 to 0.85) and kidney outcomes (P values for treatment by subgroup interactions ranged from 0.16 to 0.60). In all KDIGO risk categories, placebo and empagliflozin had similar adverse event rates, the notable exception being genital infection events, which were more common with empagliflozin for each category.

CONCLUSIONS

The observed effects of empagliflozin versus placebo on cardiovascular and kidney outcomes were consistent across the KDIGO risk categories, indicating that the effect of treatment benefit of empagliflozin was unaffected by baseline CKD status.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

EMPA-REG OUTCOME, NCT01131676.

Methylation pattern of urinary DNA as a marker of kidney function decline in diabetes

INTRODUCTION

Renal tubular injury contributes to the decline in kidney function in patients with diabetes. Cell type-specific DNA methylation patterns have been used to calculate proportions of particular cell types. In this study, we developed a method to detect renal tubular injury in patients with diabetes by detecting exfoliated tubular cells shed into the urine based on tubular cell-specific DNA methylation patterns.

RESEARCH DESIGN AND METHODS

We identified DNA methylation patterns specific for human renal proximal tubular cells through compartment-specific methylome analysis. We next determined the methylation levels of proximal tubule-specific loci in urine sediment of patients with diabetes and analyzed correlation with clinical variables.

RESULTS

We identified genomic loci in SMTNL2 and G6PC to be selectively unmethylated in human proximal tubular cells. The methylation levels of SMTNL2 and G6PC in urine sediment, deemed to reflect the proportion of exfoliated proximal tubular cells due to injury, correlated well with each other. Methylation levels of SMTNL2 in urine sediment significantly correlated with the annual decline in estimated glomerular filtration rate. Moreover, addition of urinary SMTNL2 methylation to a model containing known risk factors significantly improved discrimination of patients with diabetes with faster estimated glomerular filtration rate decline.

CONCLUSIONS

This study demonstrates that patients with diabetes with continual loss in kidney function may be stratified by a specific DNA methylation signature through epigenetic urinalysis and provides further evidence at the level of exfoliated cells in the urine that injury of proximal tubular cells may contribute to pathogenesis of diabetic kidney disease.

Kidney disease progression and all-cause mortality across estimated glomerular filtration rate and albuminuria categories among patients with vs. without type 2 diabetes

BACKGROUND

Studies of progression of kidney dysfunction typically focus on renal replacement therapy or percentage decline in estimated glomerular filtration rate (eGFR) as outcomes. Our aim was to compare real-world patients with and without T2D to estimate progression from and to clinically defined categories of kidney disease and all-cause mortality.

METHODS

This was an observational cohort study of 31,931 patients with and 33,201 age/sex matched patients without type 2 diabetes (T2D) who had a serum creatinine and urine albumin-to-creatinine ratio (UACR) or dipstick proteinuria (DP) values. We used the first available serum creatinine value between 2006 and 2012 to calculate baseline eGFR and categorized them and the corresponding UACR/DP values using the Kidney Disease Improving Global Outcomes (KDIGO) categories. To assess our primary outcomes, we extracted probabilities of eGFR progression or mortality from life-table analyses and conducted multivariable Cox regression analyses of relative risk adjusted for age, sex, race/ethnicity, smoking, ischemic heart disease, heart failure, and use of renal-angiotensin-aldosterone system inhibitors.

RESULTS

Patterns of eGFR decline were comparable among patients with vs. without T2D with larger percentage declines at higher albuminuria levels across all eGFR categories. eGFR decline was generally larger among T2D patients, particularly in those with severely increased albuminuria. Across all CKD categories, risk of progression to the next higher category of eGFR was substantially increased with increasing albuminuria. For example, the risk was 23.5, 36.2, and 65.1% among T2D patients with eGFR 30-59 ml/min/1.73m2 and UACR < 30, 30-299, and > 300 mg/dL, respectively (p < 0.001). Other comparisons were similarly significant. Among patients with low eGFR and normal to mildly increased albuminuria, the relative risk was up to 8-fold greater for all-cause mortality compared with the non-CKD subgroup (eGFR> 60 ml/min/1.73m2 with normal to mildly increased albuminuria).

CONCLUSIONS

Presence of albuminuria was associated with accelerated eGFR decline independent of T2D. Risk for adverse outcomes was remarkably high among patients with CKD and normal to mildly increased albuminuria levels. Independent of T2D or albuminuria, a substantial risk for adverse outcomes exists for CKD patients in a routine care setting.

Glomerular Filtration Rate, its Association with Risk Factors and Cardiovascular Diseases. The Results of the ESSE-RF-2 Study

Aim. To study the influence of social determinants on the frequency of glomerular filtration rate (GFR) categories of various levels, as well as associations with a number of cardiovascular diseases (CVD) and cardiovascular risk factors among the population of four Russian regions included in the ESSE-RF-2.

Material and methods. The study was performed as part of a multicenter epidemiological study “Epidemiology of cardiovascular diseases in the regions of the Russian Federation. The second study (ESSE-RF-2)”. In total, 6681 people 25-64 years old from 4 regions of Russian Federation were included in the analysis. The CKD-EPI formula was used to calculate GFR by blood creatinine level. Groups with normal GFR (≥90 ml/min/1.73 m²), with an initial decrease in GFR (<90 ml/min/1.73 m²), and with a decrease in GFR (<60 ml/min/1.73 m²) were distinguished for statistical analysis. Generalized linear/nonlinear analysis (GLM) was used for multivariate assessment and adjustment of results to socio-demographic characteristics.

Results. The average GFR level in the total sample was 97.8±16.6 ml/min/1.73 m2 ; 29.0% of individuals had an initial decrease in GFR, 1.6% had a reduced GFR. Age was significantly associated with GFR. A statistically significant association with an initial decrease in GFR was found for: hypercholesterolemia (odds ratio [OR] 1.22; 95% clearance interval [95%CI] 1.14-1.30), hypertriglyceridemia (OR 1.09; 95%CI 1.02-1.17), hyperuricemia (OR 1.51; 95%CI 1.39-1.63), no smoking (OR 0.79; 95%CI 0.73-0.85), history of kidney disease (OR 1.13; 95%CI 1.04-1.22). A more pronounced decrease in GFR was associated with the following factors and diseases: arterial hypertension (OR 1.48; 95%CI 1.07-2.05), low level of high-density lipoproteins (OR 1.36; 95%CI 1.04-1.79), hypertriglyceridemia (OR 1.37; 95%CI 1.08-1.76), hyperuricemia (OR 2.49; 95%CI 1.97-3.16), hyperglycemia (OR 1.35; 95%CI 1.01-1.80), a history of myocardial infarction (OR 1.63; 95%CI 1.13-2.36) and kidney disease (OR 1.50; 95%CI 1.16-1.93).

Conclusion. The results of the study indicate a greater number of factors and diseases associated with low GFR compared with the initial decrease, which emphasizes the need for early detection of signs of chronic kidney disease, especially in the elderly, in people with metabolic syndrome, hypertension or diabetes mellitus, as well as a history of kidney disease.

The Prognosis of Patients With Type 2 Diabetes and Nonalbuminuric Diabetic Kidney Disease Is Not Always Poor: Implication of the Effects of Coexisting Macrovascular Complications (JDDM 54)

OBJECTIVE

Nonalbuminuric diabetic kidney disease (DKD) has become the prevailing phenotype in patients with type 2 diabetes. However, it remains unclear whether its prognosis is poorer than that of other DKD phenotypes.

RESEARCH DESIGN AND METHODS

A total of 2,953 Japanese patients with type 2 diabetes and estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m², enrolled in an observational cohort study in 2004, were followed until 2015. On the basis of albuminuria (>30 mg/g creatinine) and reduced eGFR (<60 mL/min/1.73 m²) at baseline, participants were classified into the four DKD phenotypes-no-DKD, albuminuric DKD without reduced eGFR, nonalbuminuric DKD with reduced eGFR, and albuminuric DKD with reduced eGFR-to assess the risks of mortality, cardiovascular disease (CVD), and renal function decline.

RESULTS

During the mean follow-up of 9.7 years, 113 patients died and 263 developed CVD. In nonalbuminuric DKD, the risks of death or CVD were not higher than those in no-DKD (adjusted hazard ratio 1.02 [95% CI 0.66, 1.60]) and the annual decline in eGFR was slower than in other DKD phenotypes. The risks of death or CVD in nonalbuminuric DKD without prior CVD were similar to those in no-DKD without prior CVD, whereas the risks in nonalbuminuric DKD with prior CVD as well as other DKD phenotypes were higher.

CONCLUSIONS

Nonalbuminuric DKD did not have a higher risk of mortality, CVD events, or renal function decline than the other DKD phenotypes. In nonalbuminuric DKD, the presence of macrovascular complications may be a main determinant of prognosis rather than the renal phenotype.

Renal Evaluation and Protection

Diabetes and diabetic nephropathy have become more prevalent in the elderly population. Diabetic nephropathy has become increasingly prevalent in the elderly population. The presence of this disease in an age group suffering multiple comorbidities has altered the pathophysiology and leading cause of mortality. Mortality has become linked more often to cardiovascular events rather than progression of end-stage-renal-disease, which explains the recent shift of focus of trials to improving cardiovascular-outcomes in patients with diabetes. In this chapter, we emphasize the difference in treatment modalities and goals of therapy in elderly versus young. In addition, we discuss results from recent outcome trials with regards to renal benefits of sodium-glucose co-transporter-2-inhibitors and glucagon-like peptide-1-receptor-agonists.

When ESKD complicates the management of diabetes mellitus

Given the increased incidence and prevalence of ESKD (end-stage kidney disease) attributed to diabetes mellitus, it is important to consider the physiological and global sociodemographic factors that give rise to unique challenges in providing excellent care to this population. The individual with diabetes and ESKD faces alterations of glucose homeostasis that require close therapeutic attention, as well as the consideration of safe and effective means of maintaining glycemic control. Implementation of routine monitoring of blood glucose and thoughtful alteration of the individual's hypoglycemic drug regimen must be employed to reduce the risk of neurological, cardiovascular, and diabetes-specific complications that may arise as a result of ESKD. Titration of insulin therapy may become quite challenging, as kidney replacement therapy often significantly impacts insulin requirements. New medications have significantly improved the ability of the clinician to provide effective therapies for the management of diabetes, but have also raised an equal amount of uncertainty with respect to their safety and efficacy in the ESKD population. Additionally, the clinician must consider the challenges related to the delivery of kidney replacement therapy, and how inter-modality differences may impact glycemic control, diabetes, and ESKD-related complications, and issues surrounding dialysis vascular access creation.

Diabetic kidney disease: new clinical and therapeutic issues. Joint position statement of the Italian Diabetes Society and the Italian Society of Nephrology on "The natural history of diabetic kidney disease and treatment of hyperglycemia in patients with type 2 diabetes and impaired renal function"

AIMS

This joint document of the Italian Diabetes Society and the Italian Society of Nephrology reviews the natural history of diabetic kidney disease (DKD) in the light of the recent epidemiological literature and provides updated recommendations on anti-hyperglycemic treatment with non-insulin agents.

DATA SYNTHESIS

Recent epidemiological studies have disclosed a wide heterogeneity of DKD. In addition to the classical albuminuric phenotype, two new albuminuria-independent phenotypes have emerged, i.e., "nonalbuminuric renal impairment" and "progressive renal decline", suggesting that DKD progression toward end-stage kidney disease (ESKD) may occur through two distinct pathways, albuminuric and nonalbuminuric. Several biomarkers have been associated with decline of estimated glomerular filtration rate (eGFR) independent of albuminuria and other clinical variables, thus possibly improving ESKD prediction. However, the pathogenesis and anatomical correlates of these phenotypes are still unclear. Also the management of hyperglycemia in patients with type 2 diabetes and impaired renal function has profoundly changed during the last two decades. New anti-hyperglycemic drugs, which do not cause hypoglycemia and weight gain and, in some cases, seem to provide cardiorenal protection, have become available for treatment of these individuals. In addition, the lowest eGFR safety thresholds for some of the old agents, particularly metformin and insulin secretagogues, have been reconsidered.

CONCLUSIONS

The heterogeneity in the clinical presentation and course of DKD has important implications for the diagnosis, prognosis, and possibly treatment of this complication. The therapeutic options for patients with type 2 diabetes and impaired renal function have substantially increased, thus allowing a better management of these individuals.

Risk factors and urinary biomarkers of non-albuminuric and albuminuric chronic kidney disease in patients with type 2 diabetes

BACKGROUND

A number of recent studies indicate a transformation in the natural course of chronic kidney disease (CKD) in type 2 diabetes (T2D) patients: an increasing prevalence of declined renal function without proceeding to the accompanying elevation of albuminuria. It has been suggested that albuminuric and non-albuminuric CKD patterns could be different in their phenotypes and pathogenic mechanisms.

AIM

To identify the risk factors and biomarkers of albuminuric and non-albuminuric patterns of CKD in patients with T2D.

METHODS

Three hundred sixty patients with T2D duration ≥ 10 years were included in this observational cross-sectional study. The associations of a panel of demographic and clinical characteristics, complications, comorbidities, and metabolic and hematology parameters with albuminuric and non-albuminuric CKD patterns were analyzed. The urinary excretion of nephrin and podocin, two podocyte-specific markers, and WAP-four-disulfide core domain protein 2 (WFDC-2), a marker of tubulointerstitial fibrosis, was determined by ELISA in comparison with healthy controls.

RESULTS

Non-albuminuric CKD was associated with age ≥ 65 years (P = 0.0001), female sex (P = 0.04), diabetes duration ≥ 15 years (P = 0.0009), and the use of diuretics (P = 0.0005). Male sex (P = 0.01), smoking (P = 0.01), waist-to-hip ratio >1.0 (P = 0.01) and hemoglobin A1c (HbA1c) > 8.0% (P = 0.005) were risk factors for elevated albuminuria not accompanied by a decrease in estimated glomerular filtration rate (eGFR). Duration of diabetes ≥ 15 years and the use of calcium channel blockers were risk factors for albuminuria with decreased eGFR (both P = 0.01). In multivariate logistic regression analysis, age, HbA1c, female sex and diuretics were significant predictors for reduced eGFR, while waist-to-hip ratio, HbA1c and male sex were associated with elevated urinary albumin-to-creatinine ratio (UACR). Excretion of nephrin and podocin was increased in patients with albuminuria, regardless of decline in renal function (P < 0.001), correlating positively with UACR. The urinary excretion of WFDC-2 was markedly higher in men than in women (P < 0.000001). Men with T2D demonstrated increased WFDC-2 levels independently of the CKD pattern (all P < 0.05). In T2D women, WFDC-2 excretion was increased in those with reduced renal function (P ≤ 0.01), correlating negatively with eGFR.

CONCLUSION

The data provide further evidence that albuminuric and non-albuminuric CKD phenotypes correspond to different pathways of diabetic kidney disease progression.

Diabetic kidney disease: New clinical and therapeutic issues. Joint position statement of the Italian Diabetes Society and the Italian Society of Nephrology on "The natural history of diabetic kidney disease and treatment of hyperglycemia in patients with type 2 diabetes and impaired renal function"

AIMS

This joint document of the Italian Diabetes Society and the Italian Society of Nephrology reviews the natural history of diabetic kidney disease (DKD) in the light of the recent epidemiological literature and provides updated recommendations on anti-hyperglycemic treatment with non-insulin agents.

DATA SYNTHESIS

Recent epidemiological studies have disclosed a wide heterogeneity of DKD. In addition to the classical albuminuric phenotype, two new albuminuria-independent phenotypes have emerged, i.e., "nonalbuminuric renal impairment" and "progressive renal decline", suggesting that DKD progression toward end-stage kidney disease (ESKD) may occur through two distinct pathways, albuminuric and nonalbuminuric. Several biomarkers have been associated with decline of estimated glomerular filtration rate (eGFR) independent of albuminuria and other clinical variables, thus possibly improving ESKD prediction. However, the pathogenesis and anatomical correlates of these phenotypes are still unclear. Also the management of hyperglycemia in patients with type 2 diabetes and impaired renal function has profoundly changed during the last two decades. New anti-hyperglycemic drugs, which do not cause hypoglycemia and weight gain and, in some cases, seem to provide cardiorenal protection, have become available for treatment of these individuals. In addition, the lowest eGFR safety thresholds for some of the old agents, particularly metformin and insulin secretagogues, have been reconsidered.

CONCLUSIONS

The heterogeneity in the clinical presentation and course of DKD has important implications for the diagnosis, prognosis, and possibly treatment of this complication. The therapeutic options for patients with type 2 diabetes and impaired renal function have substantially increased, thus allowing a better management of these individuals.

Mitochondrial activity contributes to impaired renal metabolic homeostasis and renal pathology in STZ-induced diabetic mice

Diabetic nephropathy (DN) has become the main cause of end-stage renal disease worldwide, but the efficacy of current therapeutic strategies on DN remains unsatisfactory. Recent research has reported the involvement of metabolic rearrangement in the pathological process of DN, and of all the disturbances in metabolism, mitochondria serve as key regulatory hubs. In the present study, high-resolution mass spectrometry-based nontarget metabolomics was used to uncover the metabolic characteristics of the early diabetic kidney with or without the inhibition of mitochondrial activity. At first, we observed a moderate enhancement of mitochondrial complex-1 activity in the diabetic kidney, which was completely normalized by the specific mitochondrial complex-1 inhibitor rotenone (ROT). Meanwhile, metabolomics data indicated an overactivated pentose phosphate pathway, purine and pyrimidine metabolism, hexosamine biosynthetic pathway, and tricarboxylic acid cycle, which were strikingly corrected by ROT. In addition, ROT also strikingly corrected imbalanced redox homeostasis, possibly by increasing the ratio of antioxidant metabolites glutathione and NADPH against their oxidative form. In agreement with the improved metabolic status and oxidative response, ROT attenuated glomerular and tubular injury efficiently. Fibrotic markers (fibronectin, α-smooth muscle actin, collagen type I, and collagen type III), inflammatory factors (TNF-α, IL-1β, and ICAM-1), and oxidative stress were all markedly blocked by ROT. In vitro, ROT dose dependently attenuated high glucose-induced proliferation and extracellular matrix production in mesangial cells. Collectively, these findings revealed that the overactivation of mitochondrial activity in the kidney could contribute to metabolic disorders and the pathogenesis of early DN.

Glucometabolic characteristics and higher vascular complication risk in Korean patients with type 2 diabetes with non-albumin proteinuria

OBJECTIVE

We investigated the clinical relevance of non-albumin proteinuria (NAP) in Korean patients with type 2 diabetes (T2D).

RESEARCH DESIGN AND METHODS

We enrolled 883 T2D patients who had both their urinary albumin-to-creatinine ratio (uACR) and protein-to-creatinine ratio (uPCR) measured. We classified the patients into non-proteinuria (NP; uPCR <150 mg/g and uACR <30 mg/g), isolated NAP (iNAP; uPCR ≥150 mg/g and uACR <30 mg/g), and albuminuria (uACR ≥30 mg/g) groups. The associations between uPCR, uACR, and several indices of glucose metabolism were investigated.

RESULTS

The glucometabolic pathophysiology of iNAP (96 [10.9%]) group was more associated with a decrease in homeostatic model assessment (HOMA)-beta value (aOR 1.89 [95% CI, 1.21-2,96]) than with an increase in HOMA-insulin resistance (aOR 1.29 [95% CI, 0.83-2.01]). uPCR ≥150 mg/g was also found to have more consistent and stronger association with vascular complications than uACR ≥30 mg/g (aOR 1.44 [95% CI, 1.03-2.02] vs. 1.26 [95% CI, 0.89-1.79]).

CONCLUSIONS

The nephropathy of iNAP may be mainly attributed to decreased beta cell function. Furthermore, uPCR might be a more sensitive urinary biomarker than uACR for the detection of vascular complications in T2D patients.

Secular changes in clinical manifestations of kidney disease among Japanese adults with type 2 diabetes from 1996 to 2014

AIMS/INTRODUCTION

Diabetic kidney disease is characterized by increased albuminuria and/or a reduced glomerular filtration rate (GFR). We analyzed secular changes in the prevalence of albuminuria and reduced estimated GFR (eGFR) in Japanese patients with type 2 diabetes, and identified factors associated with these changes.

MATERIALS AND METHODS

Using 1996, 2001, 2006 and 2014 cohort data from the Japanese serial cross-sectional studies conducted at Shiga University of Medical Science, secular changes in the prevalence of diabetic kidney disease (albuminuria and/or reduced eGFR), patient characteristics and their associations were analyzed.

RESULTS

The prevalence of microalbuminuria and macroalbuminuria decreased over time, whereas the prevalence of moderately reduced eGFR (30-60 mL/min/1.73 m2 ) and severely reduced eGFR (<30 mL/min/1.73 m2 ) increased. Severely reduced eGFR was observed mainly in the patients with macroalbuminuria, regardless of year. Conversely, the prevalence of moderately reduced eGFR increased in the patients without macroalbuminuria. Both macroalbuminuria and moderately reduced eGFR without macroalbuminuria in the 2014 cohort were refractory to the recently recommended intensive therapy. Finally, we showed that obesity accompanied by vascular dysfunction was a risk factor for the development of albuminuria, and that age-dependent arterial stiffness was associated with reduced eGFR without macroalbuminuria in the 2014 cohort.

CONCLUSIONS

During the past 20 years in Japan, the prevalence of albuminuria declined, whereas that of reduced eGFR increased. Additionally, obesity- and high age-related vascular damage seems to be associated with macroalbuminuria and reduced eGFR without macroalbuminuria, respectively.

Chinese herbal medicine for diabetic kidney disease: a systematic review and meta-analysis of randomised placebo-controlled trials

OBJECTIVES

To provide a broad evaluation of the efficacy and safety of oral Chinese herbal medicine (CHM) as an adjunctive treatment for diabetic kidney disease (DKD), including mortality, progression to end-stage kidney disease (ESKD), albuminuria, proteinuria and kidney function.

DESIGN

A systematic review and meta-analysis.

METHODS

Randomised controlled trials (RCTs) comparing oral CHM with placebo as an additional intervention to conventional treatments were retrieved from five English (Cochrane Central Register of Controlled Trials, MEDLINE, Embase, Allied and Complementary Medicine Database and Cumulative Index of Nursing and Allied Health Literature) and four Chinese databases (China BioMedical Literature, China National Knowledge Infrastructure, Chonqing VIP and Wanfang) from inception to May 2018. RCTs recruiting adult DKD patients induced by primary diabetes were considered eligible, regardless of the form and ingredients of oral CHM. Mean difference (MD) or standardised mean difference (SMD) was used to analyse continuous variables and RR for dichotomous data.

RESULTS

From 7255 reports retrieved, 20 eligible studies involving 2719 DKD patients were included. CHM was associated with greater reduction of albuminuria than placebo, regardless of whether renin-angiotensin system (RAS) inhibitors were concurrently administered (SMD -0.56, 95% CI [-1.04 to -0.08], I2=64%, p=0.002) or not (SMD -0.92, 95% CI [-1.35 to -0.51], I2=87%, p<0.0001). When CHM was used as an adjunct to RAS inhibitors, estimated glomerular filtration rate was higher in the CHM than placebo group (MD 6.28 mL/min; 95% CI [2.42 to 10.14], I2=0%, p=0.001). The effects of CHM on progression to ESKD and mortality were uncertain due to low event rates. The reported adverse events in CHM group included digestive disorders, elevated liver enzyme level, infection, anaemia, hypertension and subarachnoid haemorrhage, but the report rates were low and similar to control groups. The favourable results of CHM should be balanced with the limitations of the included studies such as high heterogeneity, short follow-up periods, small numbers of clinical events and older patients with less advanced disease.

CONCLUSIONS

Based on moderate to low quality evidence, CHM may have beneficial effects on renal function and albuminuria beyond that afforded by conventional treatment in adults with DKD. Further well-conducted, adequately powered trials with representative DKD populations are warranted to confirm the long-term effect of CHM, particularly on clinically relevant outcomes.

PROSPERO REGISTRATION NUMBER

CRD42015029293.

Non-albuminuric renal impairment is a strong predictor of mortality in individuals with type 2 diabetes: the Renal Insufficiency And Cardiovascular Events (RIACE) Italian multicentre study

AIMS/HYPOTHESIS

Non-albuminuric renal impairment has become the prevailing diabetic kidney disease (DKD) phenotype in individuals with type 2 diabetes and an estimated GFR (eGFR) <60 ml min^-1 1.73 m^-2. In the present study, we compared the rate and determinants of all-cause death in individuals with this phenotype with those in individuals with albuminuric phenotypes.

METHODS

This observational prospective cohort study enrolled 15,773 individuals with type 2 diabetes in 2006-2008. Based on baseline albuminuria and eGFR, individuals were classified as having: no DKD (Alb^-/eGFR^-), albuminuria alone (Alb⁺/eGFR^-), reduced eGFR alone (Alb^-/eGFR⁺), or both albuminuria and reduced eGFR (Alb⁺/eGFR⁺). Vital status on 31 October 2015 was retrieved for 15,656 individuals (99.26%).

RESULTS

Mortality risk adjusted for confounders was lowest for Alb^-/eGFR^- (reference category) and highest for Alb⁺/eGFR⁺ (HR 2.08 [95% CI 1.88, 2.30]), with similar values for Alb⁺/eGFR^- (1.45 [1.33, 1.58]) and Alb^-/eGFR⁺ (1.58 [1.43, 1.75]). Similar results were obtained when individuals were stratified by sex, age (except in the lowest age category) and prior cardiovascular disease. In normoalbuminuric individuals with eGFR <45 ml min^-1 1.73 m^-2, especially with low albuminuria (10-29 mg/day), risk was higher than in microalbuminuric and similar to macroalbuminuric individuals with preserved eGFR. Using recursive partitioning and amalgamation analysis, prevalent cardiovascular disease and lower HDL-cholesterol were the most relevant correlates of mortality in all phenotypes. Higher albuminuria within the normoalbuminuric range was associated with death in non-albuminuric DKD, whereas the classic 'microvascular signatures', such as glycaemic exposure and retinopathy, were correlates of mortality only in individuals with albuminuric phenotypes.

CONCLUSIONS/INTERPRETATION

Non-albuminuric renal impairment is a strong predictor of mortality, thus supporting a major prognostic impact of renal dysfunction irrespective of albuminuria. Correlates of death partly differ from the albuminuric forms, indicating that non-albuminuric DKD is a distinct phenotype.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00715481.

Dickkopf-3 (DKK3) in Urine Identifies Patients with Short-Term Risk of eGFR Loss

BACKGROUND

The individual course of CKD may vary, and improved methods for identifying which patients will experience short-term eGFR loss are needed. Assessing urinary Dickkopf-3 (DKK3), a stress-induced tubular epithelia-derived profibrotic glycoprotein, may provide information about ongoing tubulointerstitial fibrosis and short-term eGFR loss.

METHODS

To investigate urinary DKK3's potential as a biomarker of short-term eGFR loss (over 12 months), we prospectively assessed eGFR and urinary DKK3 levels in patients with CKD of various etiologies at baseline and annual follow-ups. We also measured urinary DKK3 in a general population sample and patients with diagnostic kidney biopsies or IgA nephropathy under treatment.

RESULTS

Median urinary DKK3-to-creatinine concentration at baseline was significantly higher in patients with CKD than the general population sample (431 versus 33 pg/mg). In the CKD cohort, having a urinary DKK3-to-creatinine level >4000 pg/mg was independently and significantly associated after multiple adjustments with mean annual decline in eGFR of 7.6% over 12 months. Urinary DKK3 significantly improved prediction of kidney function decline compared with eGFR or albuminuria alone. Urinary DKK3-to-creatinine levels were related to the extent of tubulointerstitial fibrosis in kidney biopsies. In patients with IgA nephropathy, a rise in urinary DKK3 was associated with significant eGFR decline within 6 months, whereas stable or decreasing urinary DKK3 indicated a more favorable course.

CONCLUSIONS

Urinary DKK3 levels identify patients at high risk for eGFR decline over the next 12 months regardless of the cause of kidney injury and beyond established biomarkers, potentially providing a tool to monitor CKD progression and assess effects of interventions.