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)

Risk Prediction and Management of Chronic Kidney Disease in People Living with Type 2 Diabetes Mellitus

People with type 2 diabetes mellitus have increased risk of chronic kidney disease and atherosclerotic cardiovascular disease. Improved care delivery and implementation of guideline-directed medical therapy have contributed to the declining incidence of atherosclerotic cardiovascular disease in high-income countries. By contrast, the global incidence of chronic kidney disease and associated mortality is either plateaued or increased, leading to escalating direct and indirect medical costs. Given limited resources, better risk stratification approaches to identify people at risk of rapid progression to end-stage kidney disease can reduce therapeutic inertia, facilitate timely interventions and identify the need for early nephrologist referral. Among people with chronic kidney disease G3a and beyond, the kidney failure risk equations (KFRE) have been externally validated and outperformed other risk prediction models. The KFRE can also guide the timing of preparation for kidney replacement therapy with improved healthcare resources planning and may prevent multiple complications and premature mortality among people with chronic kidney disease with and without type 2 diabetes mellitus. The present review summarizes the evidence of KFRE to date and call for future research to validate and evaluate its impact on cardiovascular and mortality outcomes, as well as healthcare resource utilization in multiethnic populations and different healthcare settings.

Efficacy and safety of Abelmoschus manihot capsule combined with ACEI/ARB on diabetic kidney disease: a systematic review and meta analysis

Background: Diabetic kidney disease (DKD) is one of the most serious microvascular complications of diabetes, with the incidence rate increasing yearly, which is the leading cause of chronic kidney disease (CKD) and end-stage kidney disease. Abelmoschus Manihot capsule, as a proprietary Chinese patent medicine, is widely used for treating CKD in China. Currently, the combination of Abelmoschus Manihot (AM) capsule and renin-angiotensin-aldosterone system inhibitor (RASI) has gained popularity as a treatment option for DKD, with more and more randomized control trials (RCTs) in progress. However, the high-quality clinical evidence supporting its application in DKD is still insufficient. Aim of the study: To comprehensively and systematically evaluate the efficacy and safety of AM capsule combined with RASI in the treatment of DKD. Materials and methods: English and Chinese databases such as Pubmed, Cochrane Library, Embase, CNKI, SinoMed, WF, and VIP were searched to collect the RCTs of AM capsule in treatment of DKD. Then Two investigators independently reviewed and extracted data from the RCTs which met the inclusion criteria. The quality of the data was assessed using the Cochrane risk of bias assessment tool, and meta-analysis was performed using RevMan 5.4 software. Results: 32 RCTs with a total of 2,881 DKD patients (1,442 in the treatment group and 1,439 in the control group) were included. The study results showed that AM capsule combined with RASI could be more effective in decreasing 24h-UTP [MD = -442.05, 95% CI (-609.72, -274.38), p < 0.00001], UAER [MD = -30.53, 95% CI (-39.10, -21.96), p < 0.00001], UACR [MD = -157.93, 95% CI (-288.60, -27.25), p < 0.00001], Scr [MD = -6.80, 95% CI (-9.85, -3.74), p < 0.0001], and BUN [MD = -0.59, 95% CI (-1.07, -0.12), p = 0.01], compared to using RASI alone. According to the subgroup analyses, the combination of AM and ARB seems to be more effective in reducing UAER than the combination of ACEI, and the addition of AM may achieve a more significant clinical effect on decreasing Scr for DKD patients with 24h-UTP>2 g or Scr>110-133 μmol/L and >133 μmol/L. Furthermore, no additional adverse reactions were observed in the combination group [OR = 1.06; 95%CI: (0.66, 1.69), p = 0.82]. Conclusion: Combining AM with RASI may be a superior strategy for DKD treatment compared to RASI monotherapy. However, due to significant heterogeneity, the results should be interpreted with great caution, and more high-quality RCTs with multi-centers, different stages of DKD, large sample sizes, and long follow-up periods are still needed to improve the evidence quality of AM for DKD in the future. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/#recordDetails; Identifier CRD42022351422.

Medicare formulary restrictions for glucagon-like peptide 1 receptor agonists and sodium glucose cotransporter 2 inhibitors used in type 2 diabetes mellitus: 2019-2023

BACKGROUND

Glucagon-like peptide 1 receptor agonists (GLP1-RAs) and sodium glucose cotransporter 2 inhibitors (SGLT2is) have proven benefits in patients with type 2 diabetes mellitus related to decreasing cardiovascular events and heart failure hospitalizations as well as preventing the progression of kidney disease. This led the American Diabetes Association (ADA) to update their guidelines in 2022 to recommend GLP1-RAs and SGLT2is as potential first-line options in patients with cardiorenal conditions. Formulary restrictions, such as step therapy and prior authorizations, can limit access to these beneficial medications.

OBJECTIVE

To evaluate trends in Medicare formulary restrictions of GLP1-RAs and SGLT2is following the recommendations by the ADA for first-line use.

METHODS

We conducted a retrospective cohort study of Quarter 1 Medicare formulary restrictions on GLP1-RAs and SGLT2is from 2019 to 2023. We analyzed changes in formulary restrictions by year, before and after the ADA first-line recommendations, single vs combination products, and products with and without other indications on a medication level (ie, each unique National Drug Code number on each unique formulary) and formulary level (ie, any prior authorization or step therapy requirements yield formulary restriction).

RESULTS

We analyzed 12,212 unique Medicare formularies. GLP1-RAs were 12.5% less likely (relative risk [RR] = 0.87; 95% CI = 0.84-0.91; P < 0.001) and 33.2% less likely (RR = 0.67; 95% CI = 0.60-0.74; P < 0.001) to have restrictions after the ADA guideline changes on a medication and formulary level, respectively. SGLT2is were 87.8% less likely (RR = 0.12; 95% CI = 0.11-0.13; P < 0.001) and 53.0% less likely (RR = 0.47; 95% CI = 0.27-0.80; P = 0.005) to have restrictions after the ADA guideline changes on medication and formulary levels, respectively.

CONCLUSIONS

Decreasing trends of medications and formularies with restrictions may indicate payers are recognizing GLP1-RAs and SGLT2is as potential first-line agents, aligning with ADA recommendations.

Cardiovascular risk and renal injury profile in subjects with type 2 diabetes and non-albuminuric diabetic kidney disease

BACKGROUND

In the last years, the classical pattern of diabetic kidney disease (DKD) has been partially overcome, because of the uncovering of a new DKD phenotype with significant renal dysfunction without presence of albuminuria: the non-albuminuric DKD (NA-DKD). To date, the cardiovascular risk associated with this phenotype is still debated. We investigated the cardiovascular risk and renal injury profile of NA-DKD subjects in comparison with other DKD phenotypes.

METHODS

Pulse wave velocity (PWV), intima-media thickness, presence of carotid atherosclerotic plaque, renal resistive index (RRI), and a panel of urinary biomarkers of kidney injury were evaluated in 160 subjects with type 2 diabetes, stratified according to estimated glomerular filtration rate (eGFR) and urinary albumin to creatinine ratio (UACR) into four groups: controls (UACR < 30 mg/g and eGFR ≥ 60 mL/min/1.73 m2), A-DKD (Albuminuric-DKD, UACR ≥ 30 mg/g and eGFR ≥ 60 mL/min/1.73 m2), NA-DKD (UACR < 30 mg/g and eGFR < 60 mL/min/1.73 m2), AL-DKD (Albuminuric and Low eGFR-DKD; UACR ≥ 30 mg/g and eGFR < 60 mL/min/1.73 m2).

RESULTS

Subjects with NA-DKD showed a higher PWV (11.83 ± 3.74 m/s vs. 10.24 ± 2.67 m/s, P = 0.045), RRI (0.76 ± 0.11 vs. 0.71 ± 0.09, P = 0.04), and prevalence of carotid atherosclerotic plaque (59% vs. 31%, P = 0.009) compared with controls. These characteristics were similar to those of subjects with AL-DKD, whereas the profile of A-DKD subjects was closer to controls. After multiple regression analyses, we found that RRI, that is in turn influenced by eGFR (β = - 0.01, P = 0.01), was one of the major determinants of PWV (β = 9.4, P = 0.02). Urinary TreFoil Factor 3, a marker of tubular damage, was higher in NA-DKD subjects vs. controls (1533.14 ± 878.31 ng/mL vs. 1253.84 ± 682.17 ng/mL, P = 0.047). Furthermore, after multiple regression analyses, we found that urinary osteopontin was independently associated with PWV (β = 2.6, P = 0.049) and RRI (β = 0.09, P = 0.006).

CONCLUSIONS

Our data showed a worse cardiovascular and renal injury profile in NA-DKD subjects. This finding emphasizes the central role of eGFR in the definition of cardiovascular risk profile of diabetic subjects together with albuminuria.

Impact of proteinuria on long-term prognosis in patients with coronary artery disease

BACKGROUND

This study aimed to investigate the association between proteinuria and long-term prognosis in patients with coronary artery disease.

METHODS

This was a single-center observational study. A total of 1351 patients were identified who underwent percutaneous coronary intervention, and whose urine data were available. Patients were divided into two groups according to the presence (n = 245) or absence (n = 1106) of proteinuria. All-cause and cardiovascular deaths were primarily evaluated.

RESULTS

The prevalence rates of hypertension and diabetes were significantly higher, and the baseline estimated glomerular filtration rate (eGFR) was lower in patients with proteinuria than in those without proteinuria. During the median follow-up of 4.1 years (interquartile range, 1.7-6.8 years), the occurrences of all-cause and cardiovascular deaths were significantly higher in patients with proteinuria. Multivariable Cox regression analysis indicated that the presence of proteinuria was a significant predictor of cardiovascular death as well as age, BMI, reduced eGFR, and left ventricular ejection fraction. When stratified into four groups based on eGFR category (eGFR <60 or ≥60 ml/min/1.73 m2) and absence or presence of proteinuria, the incidence rates of all-cause and cardiovascular deaths were highest in patients with proteinuria and eGFR less than 60 ml/min/1.73 m2. Furthermore, the incidence rates of all-cause and cardiovascular deaths were significantly higher in patients with proteinuria among both diabetic and nondiabetic patients.

CONCLUSION

Proteinuria is associated with the long-term prognosis, and all-cause and cardiovascular deaths in patients with coronary artery disease, regardless of eGFR and the presence or absence of diabetes mellitus.

Relationship between the magnitude of body mass index reductions and remission in patients with type 2 diabetes in real world settings: Analysis of nationwide patient registry in Japan (JDDM74)

AIMS

To determine the association between the magnitude of weight loss and incidence of remission according to baseline characteristics in patients with diabetes in clinical settings.

METHODS

In total, 39 676 Japanese patients with type 2 diabetes aged ≥18 years with glycated haemoglobin (HbA1c) ≥6.5% and/or glucose-lowering drug prescription were identified from databases of specialists' clinics from 1989 and followed until September 2022. Remission was diagnosed as maintaining HbA1c <6.5% at least 3 months after cessation of a glucose-lowering drug. Factors associated with remission were evaluated by logistic regression analysis according to weight change in 1 year (i.e. ≥10%, 7.0-9.9%, 3.0-6.9% reduction, <3% change and ≥3.0% increase).

RESULTS

During the study period, 3454 remissions occurred. The rates of remission were higher in the group with the greatest reduction of body mass index (BMI) in any category examined (i.e. baseline BMI, HbA1c, duration of diabetes and treatment). The incidences of remission per 1000 person-years were about 25 and 50, respectively, for those with BMI ≥22.5 and reductions in BMI of 7.0-9.9% and ≥10% in 1 year. Remissions per 1000 person-years were 99.2 and 91.8, respectively, for those with baseline HbA1c of 6.5-6.9 and a 10% BMI reduction and those not taking glucose-lowering drugs accompanied by a 10% BMI reduction.

CONCLUSIONS

Modest weight losses of 3.0-7.9% were significantly associated with remission, but a minimum of 10% weight loss would be required in addition to an early diagnosis to achieve a 10% remission rate in clinical settings. Our results implied that remission may be expected with a relatively lower BMI in an Asian population compared with that was reported in Western populations if accompanied by weight loss.

Lost in translation: assessing the nomenclature change for diabetic kidney disease in Japan

Recently in Japan, the term "tonyobyo sei jinzobyo", the Japanese translation of "diabetic kidney disease", has been increasingly used in place of the term "tonyobyo sei jinsho", the Japanese translation of "diabetic nephropathy". Many international diabetes and nephrology guidelines have defined diabetic kidney disease as a condition caused by diabetes, typically presenting with albuminuria, similar to or identical to current and historical definitions for diabetic nephropathy. However, recent guidelines from the Japanese Society of Nephrology propose a broader disease concept for the term diabetic kidney disease, including patients without albuminuria. A rationale for proposing a broader disease concept for diabetic kidney disease may have come from changes in the kidney phenotype of patients with diabetes observed in recent years. Epidemiological studies have shown that an increasing proportion of patients with diabetes have reduced kidney function, while the prevalence of those with albuminuria appears to have decreased. However, these studies also suggested that the more advanced age of patients presenting with diabetes and increased use of renin-angiotensin system blockers may have contributed to this change in disease phenotype. We believe the principal rationale for the nomenclature change from diabetic nephropathy to diabetic kidney disease was to create a more easily understood, lay-language term for English speakers, rather than to create a term to encompass a broader population of diabetes with chronic kidney disease (CKD). Further discussion and international consensus are needed for the definition of diabetic kidney disease, to avoid ambiguity or possible confusion.

Two-Year Changes in Diabetic Kidney Disease Phenotype and the Risk of Heart Failure: A Nationwide Population-Based Study in Korea

BACKGRUOUND

Diabetic kidney disease (DKD) is a risk factor for hospitalization for heart failure (HHF). DKD could be classified into four phenotypes by estimated glomerular filtration rate (eGFR, normal vs. low) and proteinuria (PU, negative vs. positive). Also, the phenotype often changes dynamically. This study examined HHF risk according to the DKD phenotype changes across 2-year assessments.

METHODS

The study included 1,343,116 patients with type 2 diabetes mellitus (T2DM) from the Korean National Health Insurance Service database after excluding a very high-risk phenotype (eGFR <30 mL/min/1.73 m2) at baseline, who underwent two cycles of medical checkups between 2009 and 2014. From the baseline and 2-year eGFR and PU results, participants were divided into 10 DKD phenotypic change categories.

RESULTS

During an average of 6.5 years of follow-up, 7,874 subjects developed HHF. The cumulative incidence of HHF from index date was highest in the eGFRlowPU- phenotype, followed by eGFRnorPU+ and eGFRnorPU-. Changes in DKD phenotype differently affect HHF risk. When the persistent eGFRnorPU- category was the reference, hazard ratios for HHF were 3.10 (95% confidence interval [CI], 2.73 to 3.52) in persistent eGFRnorPU+ and 1.86 (95% CI, 1.73 to 1.99) in persistent eGFRlowPU-. Among altered phenotypes, the category converted to eGFRlowPU+ showed the highest risk. In the normal eGFR category at the second examination, those who converted from PU- to PU+ showed a higher risk of HHF than those who converted from PU+ to PU-.

CONCLUSION

Changes in DKD phenotype, particularly with the presence of PU, are more likely to reflect the risk of HHF, compared with DKD phenotype based on a single time point in patients with T2DM.

Incidence and predictors of remission and relapse of type 2 diabetes mellitus in Japan: Analysis of a nationwide patient registry

AIMS

To determine the incidence of remission and 1-year relapse from remission and associated factors in patients with type 2 diabetes.

MATERIALS AND METHODS

A total of 48 320 Japanese patients with type 2 diabetes aged ≥18 years, with glycated haemoglobin (HbA1c) levels ≥48 mmol/mol (6.5%) and/or glucose-lowering drug prescription, were identified from databases of specialist clinics from 1989 and followed until September 2022. Remission was defined as HbA1c <48 mmol/mol at least 3 months after cessation of a glucose-lowering drug. Relapse was defined as failure to maintain remission for 1 year. Factors associated with remission and relapse were evaluated by logistic regression analysis.

RESULTS

The overall incidence of remissions per 1000 person-years was 10.5, and for those with HbA1c levels of 48 to 53 mmol/mol (6.5% to 6.9%), those taking no glucose-lowering drugs at baseline, and those with a ≥10% body mass index (BMI) reduction in 1 year, it was 27.8, 21.7 and 48.2, respectively. Shorter duration, lower baseline HbA1c, higher baseline BMI, higher BMI reduction at 1 year, and no glucose-lowering drugs at baseline were significantly associated with remission. Among 3677 persons with remission, approximately two-thirds (2490) relapsed within 1 year. Longer duration, lower BMI at baseline, and lower BMI reduction at 1 year were significantly associated with relapse.

CONCLUSIONS

The results showed that the incidence of remission and predictors of relapse, especially baseline BMI, might differ greatly between East Asian and Western populations. Furthermore, the relationships of BMI reduction with remission and relapse may be greater in East Asian than in Western populations, implying ethnic differences in returning from overt hyperglycaemia to nearly normal glucose levels.

Update on Diabetic Kidney Disease (DKD): Focus on Non-Albuminuric DKD and Cardiovascular Risk

The classic description of diabetic kidney disease (DKD) involves progressive stages of glomerular hyperfiltration, microalbuminuria, proteinuria, and a decline in the estimated glomerular filtration rate (eGFR), leading to dialysis. In recent years, this concept has been increasingly challenged as evidence suggests that DKD presents more heterogeneously. Large studies have revealed that eGFR decline may also occur independently from the development of albuminuria. This concept led to the identification of a new DKD phenotype: non-albuminuric DKD (eGFR < 60 mL/min/1.73 m², absence of albuminuria), whose pathogenesis is still unknown. However, various hypotheses have been formulated, the most likely of which is the acute kidney injury-to-chronic kidney disease (CKD) transition, with prevalent tubular, rather than glomerular, damage (typically described in albuminuric DKD). Moreover, it is still debated which phenotype is associated with a higher cardiovascular risk, due to contrasting results available in the literature. Finally, much evidence has accumulated on the various classes of drugs with beneficial effects on DKD; however, there is a lack of studies analyzing the different effects of drugs on the various phenotypes of DKD. For this reason, there are still no specific guidelines for therapy in one phenotype rather than the other, generically referring to diabetic patients with CKD.

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.

Albuminuric diabetic kidney disease predicts foot ulcers in type 2 diabetes

Diabetic Foot Ulcers (DFU) are feared among individuals with diabetic kidney disease (DKD), but it is unclear whether they are more frequent, especially in normoalbuminuric DKD. Five hundred and twenty patients admitted in our diabetology ward from 2007 to 2017 were followed up during 54 ± 26 months. New DFUs were registered, and their relationship with the initial renal status was analyzed by LogRank and multivariate Cox regression analysis. The 520 subjects were mainly men (57.9 %), 62 ± 9 years old, with a duration of diabetes of 14 ± 10 years, HbA1c: 8.7 ± 1.8 % (72 ± 19 mmol/mol), and complications: 33.7 % macroangiopathies, 22.1 % previous foot ulcers, 44.8 % DKD, 26.9 % retinopathies. Fifty-seven new DFU occurred, mainly in subjects with DKD. DKD was related to later DFU (HR: 1.79; 95%CI: 1.05-3.07), this relationship stayed significant adjusted for age, gender, and a history of previous DFU (HR: 3.61; 95%CI: 2.11-6.18), and further adjusted for the duration of diabetes, HbA1c, BMI, arterial hypertension, and dyslipidemia. Among the 233 subjects with DKD, 129 (55.3 %) had an isolated AER > 30 mg/24H, 41 (17.6 %) had an isolated eGFR<60 mL/min/1.73 m², and 63 (27.0 %) cumulated both abnormalities. By Cox regression analysis adjusted for age and gender, albuminuric DKDs were related to later DFU: with eGFR≥60: HR: 1.91; 95%CI: 1.02-3.59, with eGFR<60: HR: 2.53; 95%CI: 1.25-5.10, whereas normoalbuminuric DKD was not: HR: 1.04; 95%CI: 0.35-3.07, despite similar rates of neuropathies, peripheral arterial diseases, and retinopathies. In people with type 2 diabetes, albuminuric DKD was associated with two to three folds increased risk of DFUs, whereas normoalbuminuric DKD was not.

Association of the estimated glomerular filtration rate (eGFR) and/or proteinuria to predict the risk of initiation of dialysis in people with and without diabetes

Aims

To determine the associations between combined urinary protein (UP) and a reduced estimated glomerular filtration rate (eGFR) and the risk of starting dialysis with or without diabetes mellitus (DM).

Methods

A nationwide database with claims data on 335,778 people with and without DM aged 19-72 years in Japan was used to elucidate the impact of the severities of UP and eGFR on starting dialysis. Initiation of dialysis was determined from claims using ICD-10 codes and medical procedures. Using multivariate Cox modeling, we investigated the severities of UP and eGFR to predict the initiation of dialysis with and without DM.

Results

Both eGFR < 60 and UP(+) were independent predictors for starting dialysis with and without DM, and their values exhibited a synergistic risk of dialysis. eGFR < 60 presented a nearly twofold risk for starting dialysis compared to UP(+) regardless of DM. Risk of starting dialysis was increased with UP(+) and eGFR ≥ 60 accompanied by DM although this association was not observed without DM. Those who had UP(-) and eGFR < 60 had a high risk of starting dialysis regardless of DM. Compared with DM(-)UP(-)eGFR ≥ 60, HRs for starting dialysis for DM(+)UP(+)eGFR ≥ 60, DM(+)UP(-)eGFR < 60 and DM(+)UP(+)eGFR < 60 significantly increased 17.7 (10.6-29.7), 25.5 (13.8-47.1) and 358.1 (239.1-536.5) times, respectively.

Conclusions

eGFR < 60 and UP(+) together presented an extremely high risk of dialysis especially with DM. UP( +) increased the risk of starting dialysis regardless of the eGFR with DM. Both patient education and a treatment strategy by physicians might be helpful to avoid the progression of renal failure.

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.

The critical role of dysregulated autophagy in the progression of diabetic kidney disease

Diabetic kidney disease (DKD) is one of the major public health problems in society today. It is a renal complication caused by diabetes mellitus with predominantly microangiopathy and is a major cause of end-stage renal disease (ESRD). Autophagy is a metabolic pathway for the intracellular degradation of cytoplasmic products and damaged organelles and plays a vital role in maintaining homeostasis and function of the renal cells. The dysregulation of autophagy in the hyperglycaemic state of diabetes mellitus can lead to the progression of DKD, and the activation or restoration of autophagy through drugs is beneficial to the recovery of renal function. This review summarizes the physiological process of autophagy, illustrates the close link between DKD and autophagy, and discusses the effects of drugs on autophagy and the signaling pathways involved from the perspective of podocytes, renal tubular epithelial cells, and mesangial cells, in the hope that this will be useful for clinical treatment.

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.

The risk of Parkinson's disease according to diabetic kidney disease status in a Korean population

INTRODUCTION

Type 2 diabetes is a risk factor for Parkinson's disease (PD). Recently, it has been reported that proteinuria without reduced estimated glomerular filtration rate (eGFR) can increase the risk of PD development. The objective of this study was to evaluate the risk of PD among Korean adults with type 2 diabetes stratified by proteinuria (PU) and eGFR levels.

METHODS

Using the Korean National Health Insurance Service database, a total of 2,217,326 patients with type 2 diabetes who underwent regular health check-ups from 2009 to 2012 were included. These patients were classified into four groups (no-diabetic kidney disease (DKD) (PU^-GFR^-), proteinuric DKD with normal eGFR (PU⁺GFR^-), nonproteinuric DKD (PU^-GFR⁺), and proteinuric DKD with reduced eGFR (PU⁺GFR⁺) and followed up until 2018. PD was defined using International Classification of Diseases, 10th revision.

RESULTS

The prevalence of PU^-GFR^-, PU⁺GFR^-, PU^-GFR⁺, or PU⁺GFR⁺ phenotype was 83.3%, 5.0%, 10.1%, or 1.6%, respectively. During a median follow-up of 7.2 years, 16,079 participants developed PD. Hazard ratios for PD were 1.10 (95% confidence interval [CI]: 1.01-1.21, p = 0.0091), 1.15 (95% CI: 1.09-1.21, p < 0.0001), and 1.23 (95% CI: 1.09-1.39, p < 0.0001) for participants in PU⁺GFR^-, PU^-GFR⁺, and PU⁺GFR⁺ groups relative to those in the PU^-GFR^- group, respectively. Effects of DKD on PD were more pronounced in those aged less than 65 years.

CONCLUSION

Reduced eGFR and/or proteinuria might be independent risk factors for boosting PD development among patients with type 2 diabetes. More attention should be paid to PD in patients with DKD, even in a younger aged population.

Re-understanding and focusing on normoalbuminuric diabetic kidney disease

Diabetes mellitus (DM) has grown up to be an important issue of global public health because of its high incidence rate. About 25% of DM patients can develop diabetic foot/ulcers (DF/DFU). Diabetic kidney disease (DKD) is the main cause of end-stage kidney disease (ESKD). DF/DFU and DKD are serious complications of DM. Therefore, early diagnosis and timely prevention and treatment of DF/DFU and DKD are essential for the progress of DM. The clinical diagnosis and staging of DKD are mostly based on the urinary albumin excretion rate (UAER) and EGFR. However, clinically, DKD patients show normoalbuminuric diabetic kidney disease (NADKD) instead of clinical proteinuria. The old NADKD concept is no longer suitable and should be updated accordingly with the redefinition of normal proteinuria by NKF/FDA. Based on the relevant guidelines of DM and CKD and combined with the current situation of clinical research, the review described NADKD from the aspects of epidemiology, pathological mechanism, clinical characteristics, biomarkers, disease diagnosis, and the relationship with DF/DFU to arouse the new understanding of NADKD in the medical profession and pay attention to it.

Kidney outcomes and all-cause mortality in people with type 2 diabetes exhibiting non-albuminuric kidney insufficiency

AIM/HYPOTHESIS

It remains unclear whether people with diabetes exhibiting non-albuminuric kidney insufficiency have higher risk of kidney function decline and mortality compared with those exhibiting preserved kidney function without albuminuria. Furthermore, information regarding the incidence of albuminuria in people with this unique phenotype is sparse. Here, we aimed to elucidate the risk of the kidney outcomes and all-cause mortality in people with diabetes exhibiting non-albuminuric kidney insufficiency.

METHODS

In this retrospective cohort study, 8320 Japanese adults with type 2 diabetes were classified into four groups based on the presence of albuminuria and kidney insufficiency at baseline, defined as urinary albumin/creatinine ratio of equal to or above 30 mg/g and eGFR of less than 60 ml min^-1 1.73 m^-2, respectively. The primary composite kidney endpoint was a 50% decrease in eGFR from baseline or the initiation of kidney replacement therapy. The annual percentage change in eGFR slope and progression of albuminuria category were evaluated as the secondary and tertiary kidney endpoints, respectively. All-cause death was also set as the endpoint.

RESULTS

Compared with people exhibiting non-albuminuric preserved kidney function, those with non-albuminuric kidney insufficiency had the higher risk for the primary kidney endpoint (HR 4.1; 95% CI 2.5, 6.7; p < 0.001), steep percentage change in eGFR slope (-1.96%/year vs -1.36%/year, p < 0.001), incidence of albuminuria (HR 2.1; 1.7, 2.6; p < 0.001) and all-cause mortality (HR 1.5; 1.2, 2.0; p = 0.003). In the sensitivity analyses treating the incidence of albuminuria as a competing risk, people with non-albuminuric kidney insufficiency still had higher risk for the primary kidney endpoint and all-cause mortality than those with non-albuminuric preserved kidney function (subdistribution HR 2.8; 1.4, 5.6; p = 0.004; and 1.6; 1.1, 2.2; p = 0.014, respectively).

CONCLUSIONS/INTERPRETATION

People with type 2 diabetes exhibiting non-albuminuric kidney insufficiency had poorer kidney outcomes and life prognosis than those exhibiting non-albuminuric preserved kidney function.

Comparison of Nonalbuminuric and Albuminuric Diabetic Kidney Disease Among Patients With Type 2 Diabetes: A Systematic Review and Meta-Analysis

BACKGROUND

Diabetic kidney disease (DKD) is one of most common complications of diabetes. Recently, the classical phenotype of DKD, which is characterized by albuminuria preceding renal insufficiency, has been challenged since a subset of diabetic patients with renal insufficiency but without albuminuria has been increasingly reported. However, the available evidence is inconsistent. Thus, the present systematic review will assess and summarize the available data regarding nonalbuminuric diabetic kidney disease (NADKD).

METHODS

PubMed, Embase, and Cochrane were searched for clinical trials related to NADKD. The results were limited to full-text articles published in English, without restrictions on the publication time. The quality of clinical trials was appraised, and the data were extracted. Meta-analysis was conducted using a random-effects model. Descriptive analysis was performed if the data were insufficient.

RESULTS

A final total of 31 articles were included in this review. The meta-analysis of 18 studies showed that compared with albuminuric DKD, patients with NADKD were older (MD = 1.04 years old, 95% CI [0.52, 1.57], p < 0.05); were more often women (Male RR = 0.74, 95% CI [0.68, 0.81], p < 0.05); had shorter diabetes duration (MD = -2.9 years, 95% CI [-3.63, -2.18], p < 0.05), lower HbA1c levels (MD = -0.34%, 95% CI [-0.42, -0.25], p < 0.05), and lower blood pressure (systolic blood pressure MD = -6.21 mmHg, 95% CI [-9.41, -3.0], p < 0.05; diastolic blood pressure MD = -1.27 mmHg, 95% CI [-2.15, 4.0], p < 0.05); less frequently experienced diabetic retinopathy (RR = 0.58, 95% CI [0.51, 0.67], p < 0.05); and less frequently used renin-angiotensin-aldosterone system (RAAS) inhibitors. The underlying pathology of NADKD might be different from that of the classic phenotype of DKD, which is associated with more advanced tubulointerstitial and vascular lesions but mild typical glomerular lesions. The annual estimated glomerular filtration rate decline tended to be lower in patients with NADKD than in those with albuminuric DKD. The risk for cardiovascular disease, end-stage renal disease, and all-cause death was lower for patients with NADKD than patients with albuminuric DKD.

CONCLUSIONS

The prevalence of NADKD has increased in recent decades, and its characteristics, pathology, and prognosis are different from those of albuminuric DKD; thus, diagnosis and treatment strategies should be different. More attention should be given to this phenotype.

Insulin Resistance is Associated with Clinical Manifestations of Diabetic Kidney Disease (Glomerular Hyperfiltration, Albuminuria, and Kidney Function Decline)

Clinical features of diabetic kidney disease include glomerular hyperfiltration, albuminuria, and kidney function decline towards End-Stage Kidney Disease (ESKD). There are presently neither specific markers of kidney involvement in patients with diabetes nor strong predictors of rapid progression to ESKD. Serum-creatinine-based equations used to estimate glomerular filtration rate are notoriously unreliable in patients with diabetes. Early kidney function decline, reduced glomerular filtration rate, and proteinuria contribute to identifying diabetic patients at higher risk for rapid kidney function decline. Unlike proteinuria, the elevation of urinary albumin excretion in the range of microalbuminuria is frequently transient in patients with diabetes and does not always predict progression towards ESKD. Although the rate of progression of kidney function decline is usually accelerated in the presence of proteinuria, histological lesions of diabetes and ESKD may occur with normal urinary albumin excretion. No substantial reduction in the rate of ESKD associated with diabetes has been observed during the last decades despite intensified glycemic control and reno-protective strategies, indicating that existing therapies do not target underlying pathogenic mechanisms of kidney function decline. Very long-term effects of sodium-glucose transporters- 2 inhibitors and glucagon-like peptide-1 analogs remain to be defined. In patients with diabetes, glucagon secretion is typically elevated and induces insulin resistance. Insulin resistance is consistently and strongly associated with clinical manifestations of diabetic kidney disease, suggesting that reduced insulin sensitivity participates in the pathogenesis of the disease and may represent a therapeutic objective. Amelioration of insulin sensitivity in patients with diabetes is associated with cardioprotective and kidney-protective effects.

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.

Trajectories of kidney function in diabetes: a clinicopathological update

Diabetic nephropathy has been traditionally diagnosed based on persistently high albuminuria and a subsequent decline in glomerular filtration rate (GFR), which is widely recognized as the classical phenotype of diabetic kidney disease (DKD). Several studies have emphasized that trajectories of kidney function in patients with diabetes (specifically, changes in GFR and albuminuria over time) can differ from this classical DKD phenotype. Three alternative DKD phenotypes have been reported to date and are characterized by albuminuria regression, a rapid decline in GFR, or non-proteinuric or non-albuminuric DKD. Although kidney biopsies are not typically required for the diagnosis of DKD, a few studies of biopsy samples from patients with DKD have demonstrated that changes in kidney function associate with specific histopathological findings in diabetes. In addition, various clinical and biochemical parameters are related to trajectories of GFR and albuminuria. Collectively, pathological and clinical characteristics can be used to predict trajectories of GFR and albuminuria in diabetes. Furthermore, cohort studies have suggested that the risks of kidney and cardiovascular outcomes might vary among different phenotypes of DKD. A broader understanding of the clinical course of DKD is therefore crucial to improve risk stratification and enable early interventions that prevent adverse outcomes.

Relation of renal function to mid-term prognosis of stable angina patients with high- or low-dose pitavastatin treatment: REAL-CAD substudy

BACKGROUND

It has not yet been established whether higher-dose statins have beneficial effects on cardiovascular events in patients with stable coronary artery disease (CAD) and renal dysfunction.

METHODS

The REAL-CAD study is a prospective, multicenter, open-label trial. As a substudy, we categorized patients by an estimated glomerular filtration rate (eGFR) as follows: eGFR ≥60 (n = 7,768); eGFR ≥45 and <60 (n = 3,176); and eGFR <45 mL/Min/1.73 m² (n = 1,164), who were randomized to pitavastatin 4mg or 1mg therapy. The primary endpoint was a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal ischemic stroke, or unstable angina, and was assessed by the log-rank test and Cox proportional hazards model.

RESULTS

The baseline characteristics and medications were largely well-balanced between two groups. The magnitude of low-density lipoprotein cholesterol (LDL-C) reduction at 6 months in high- and low-dose pitavastatin groups was comparable among all eGFR categories. During a median follow-up of 3.9 years, high- compared with low-dose pitavastatin significantly reduced cardiovascular events in patients with eGFR ≥60 (hazard ratio (HR) 0.73; 95% confidence interval (CI) 0.58-0.91; P = .006), and reduced but not significant for patients with eGFR ≥45 and <60 (HR 0.85; 95% CI, 0.63-1.14; P = .27) or eGFR <45 mL/Min/1.73 m² (HR 0.90; 95% CI 0.62-1.33; P = .61). An interaction test of treatment by eGFR category was not significant (P value for interaction = .30).

CONCLUSION

Higher-dose pitavastatin therapy reduced LDL levels and cardiovascular events in stable CAD patients irrespective of eGFR level, although the effect on events appeared to be numerically lower in patients with lower eGFR.

Incidence and risk factors for mortality and end-stage renal disease in people with type 2 diabetes and diabetic kidney disease: a population-based cohort study in the UK

INTRODUCTION

We aimed to determine the incidence of, and risk factors for all-cause/cardiovascular disease (CVD) mortality, and end-stage renal disease (ESRD) among people with type 2 diabetes with/without diabetic kidney disease (DKD) in the UK general population.

RESEARCH DESIGN AND METHODS

We undertook a population-based cohort study using primary care UK electronic health records. We followed 8413 people with type 2 diabetes and DKD and a matched comparison cohort of people with type 2 diabetes without DKD. Risk factors for all-cause/CVD mortality (using both cohorts) and ESRD (DKD cohort only) were evaluated by estimating HRs with 95% CIs using Cox regression.

RESULTS

In the DKD cohort (mean age 66.7 years, 62.4% male), incidence rates per 1000 person-years were 50.3 (all-cause mortality), 8.0 (CVD mortality) and 6.9 (ESRD). HRs (95% CIs; DKD vs comparison cohort) were 1.49 (1.35 to 1.64) for all-cause mortality and 1.60 (1.24 to 2.05) for CVD mortality. In general, higher all-cause mortality risks were seen with older age, underweight (body mass index <20 kg/m²), reduced renal function, and cardiovascular/liver disease, and lower risks were seen with being female or overweight. In the DKD cohort, higher risks of ESRD were seen with reduced renal function at baseline, high material deprivation, cancer and non-insulin glucose-lowering drugs, and a lower risk was seen with overweight (≥25 kg/m²).

CONCLUSIONS

Annually, one death will occur among every 20 people with type 2 diabetes and DKD. The identified risk factors in this study will help identify people with type 2 diabetes at most risk of death and progression of kidney disease, and help to direct effective management strategies.

Comorbidities and complications in Japanese patients with type 2 diabetes mellitus: Retrospective analyses of J-DREAMS, an advanced electronic medical records database

AIMS

To investigate the prevalence of comorbid conditions/complications among Japanese patients with type 2 diabetes mellitus (T2DM) in a real-world setting.

METHODS

We performed retrospective analyses of a large-scale database directly linked to electronic medical records, J-DREAMS (Japan Diabetes compREhensive database project based on an Advanced electronic Medical record System), to determine the prevalence of clinically significant comorbid conditions/complications among Japanese patients with T2DM aged ≥ 20 years with ≥ 1 clinical encounter at a referral center between April 1, 2017 and March 31, 2019.

RESULTS

Data were available for 10,151 patients (39.2% female). The mean age and T2DM duration were 66.0 years and 16.1 years, respectively. Only 0.5% had isolated T2DM, 6.6% had one comorbid condition/complication, and the remainder had multiple comorbid conditions/complications. Dyslipidemia (84.7%) and hypertension (75.1%) were the most common, followed by chronic kidney disease (35.4%), retinopathy (23.1%), and cardiovascular diseases (22.1%). Overall, 36.0% of patients were overweight/obese (body mass index ≥ 25 kg/m²) and 18.6% had a history of neoplasms. The prevalence of comorbid conditions/complications tended to increase with advancing age and duration of T2DM.

CONCLUSIONS

We revealed a high prevalence of comorbid conditions/complications, including chronic kidney and cardiovascular diseases, in Japanese patients with T2DM.

One-year estimated glomerular filtration rate decline as a risk factor of cardiovascular and renal end-points in high-risk Japanese patients

AIMS/INTRODUCTION

As estimated glomerular filtration rate (eGFR) progression might correlate with cardiovascular prognosis, the correlation between 1-year decline in eGFR and cardiovascular incidences and renal outcome was investigated.

MATERIALS AND METHODS

The 1-year percentage decline in eGFR at the first observation year was calculated in a cohort of the standard versus intEnsive statin therapy for hypercholesteroleMic Patients with diAbetic retinopaTHY (EMPATHY) trial participants. The primary end-point was the composite cardiovascular end-point including the renal end-point. The associations between the incidence of each end-point and clinical markers were analyzed using the Cox proportional hazards regression model.

RESULTS

A total of 4,461 patients were analyzed. The mean observation period was 765.3 ± 363.1 days. The best cut-off value of 1-year eGFR decline was 0.099 in the first year for renal end-point prediction by receiver operating characteristic curve analysis. The area under the curve of the model including the 1-year eGFR decline of the first year was significantly larger than the model without it (0.943, 95% confidence interval 0.915-0.971 to 0.967, 95% confidence interval 0.950-0.983, P = 0.019). Primary end-point incidences and the renal end-point were much higher in rapid eGFR decliners compared with non-decliners (P < 0.0001). The cardiovascular end-point incidence, except for the renal end-point, was not different between the groups. According to Cox regression analysis, 1-year eGFR decline during the first year was a significant risk factor for the end-points, including the renal end-point, independent of albuminuria and eGFR at baseline.

CONCLUSIONS

The 1-year eGFR decline rate provided useful information for cardiovascular end-point predictions, including the renal end-point, in addition to the conventional risk factors.

An evaluation of canagliflozin for the treatment of type 2 diabetes: an update

IntroductionSodium-glucose cotransporter-2 inhibitors (SGLT2is) are proven to ameliorate kidney and heart failure in patients with type 2 diabetes (T2D), in addition to improving glycemic controls. Canagliflozin is a SGLT2i and has proved beneficial for kidney and heart diseases in addition to decreasing the incidence of the composite outcomes of cardiovascular diseases and stroke.Areas coveredThis paper reviews the development of canagliflozin and its effects on renal dysfunction, heart failure, and vascular diseases.Expert opinionCanagliflozin contributes to the inhibition of renal function, decline progression and, therefore, is effective for T2D patients with chronic kidney dysfunction and albuminuria. The Canagliflozin Cardiovascular Assessment Study (CANVAS) revealed that patients showed increased incidence of amputation via unknown mechanisms, which has not been observed in other studies that used real-world data. Moreover, canagliflozin has been proven effective for anemia-associated outcomes of chronic kidney failure. Meta-analyses have revealed that canagliflozin contributed to lower diastolic blood pressure when compared with other SGLT2is. A subanalysis of CANVAS data proved that canagliflozin reduced the risk of hemorrhagic stroke. Canagliflozin should be used for T2D patients with chronic kidney failure and/or albuminuria and those with vascular diseases, with monitoring for ulcers and/or the pulse on the lower limb.

Recent evidence in the etiology and treatment for diabetic kidney disease

Etiology and therapeutic targets of diabetic nephropathy.

Current trends in diabetes mellitus database research in Japan

With the widespread use of electronic medical records and administrative claims databases, analytic results from so-called real-world data have become increasingly important in healthcare decision-making. Diabetes mellitus is a heterogeneous condition that involves a broad spectrum of patients. Real-world database studies have been recognised as a powerful tool to understand the impact of current practices on clinical courses and outcomes, such as long-term glucose control, development of microvascular or macro-vascular diseases, and mortality. Diabetes is also a major global health issue and poses a significant social and economic burden worldwide. Therefore, it is critical to understand the epidemiology, clinical course, treatment reality, and long-term outcomes of diabetes to determine realistic solutions to a variety of disease-related issues that we are facing. In the present review, we summarise the healthcare system and large-scale databases currently available in Japan, introduce the results from recent database studies involving Japanese patients with diabetes, and discuss future opportunities and challenges for the use of databases in the management of diabetes.

Initial dip predicts renal protective effects after the administration of sodium-glucose cotransporter 2 inhibitors in patients with type 2 diabetes and chronic kidney disease with normoalbuminuria

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Investigated renoprotective effect of SGLT2is in T2DM and CKD with normoalbuminuria.

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More favorable effects of SGLT2is on renal function were observed.

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Higher initial dip was possible marker of worsening renal function.

Introduction

We investigated the renoprotective effects of sodium-glucose cotransporter 2 inhibitors (SGLT2is) on renal function in patients with type 2 diabetes and chronic kidney disease (CKD) with normoalbuminuria.

Methods

A retrospective review of clinical records of Japanese participants with type 2 diabetes and CKD (estimated glomerular filtration rate [eGFR] < 60 mL/min/1.73 m²) with normoalbuminuria (urine albumin to creatinine ratio < 30 mg/g Cr and/or urinary protein to creatinine ratio < 150 mg/g Cr) was conducted. Participants were categorized into two groups depending on whether they had started using SGLT2is. The main study outcome was a comparison of the change in renal function evaluated by eGFR after 1 year between the two groups. Then, we identified predictors that were associated with the outcome.

Results

Among the 46 participants, 21 were treated with SGLT2is (SGLT2 group) and 25 were treated with other antidiabetic medications (control group). Although eGFR was significantly decreased at 1 year in the control group, the decline in eGFR was not observed in the SGLT2 group. The decrease in eGFR was significantly smaller in the SGLT2 group than in the control group. Additionally, multiple linear regression analysis showed that an initial dip was an independent factor associated with the worsening of renal function in the SGLT2 group.

Conclusions

Although more favorable effects of SGLT2is on renal function were observed in patients with type 2 diabetes and CKD with normoalbuminuria, the higher initial dip was a possible marker of worsening renal function after the initiation of SGLT2is.

Significance of Metformin Use in Diabetic Kidney Disease

Metformin is a glucose-lowering agent that is used as a first-line therapy for type 2 diabetes (T2D). Based on its various pharmacologic actions, the renoprotective effects of metformin have been extensively studied. A series of experimental studies demonstrated that metformin attenuates diabetic kidney disease (DKD) by suppressing renal inflammation, oxidative stress and fibrosis. In clinical studies, metformin use has been shown to be associated with reduced rates of mortality, cardiovascular disease and progression to end-stage renal disease (ESRD) in T2D patients with chronic kidney disease (CKD). However, metformin should be administered with caution to patients with CKD because it may increase the risk of lactic acidosis. In this review article, we summarize our current understanding of the safety and efficacy of metformin for DKD.