Randomized trial of an intensified, multifactorial intervention in patients with advanced-stage diabetic kidney disease: Diabetic Nephropathy Remission and Regression Team Trial in Japan (DNETT-Japan)

Glycaemic control and macrovascular and microvascular outcomes: A systematic review and meta-analysis of trials investigating intensive glucose-lowering strategies in people with type 2 diabetes

AIM

We aimed to determine the macrovascular and microvascular outcomes of intensive versus standard glucose-lowering strategies in type 2 diabetes (T2D) and investigate the relationships between these outcomes and trial arm glycated haemoglobin (HbA1c) reduction.

MATERIALS AND METHODS

In this systematic review and meta-analysis, we identified relevant trials from MEDLINE, Embase, the Cochrane Library, and bibliographies up to August 2023. Macrovascular and microvascular outcomes, along with safety outcomes, were evaluated. Pooled study-specific hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated, and meta-regression was employed to analyse the relationships between outcomes and HbA1c reduction.

RESULTS

We included 11 unique RCTs involving 51 469 patients with T2D (intensive therapy, N = 26 691; standard therapy, N = 24 778). Intensive versus standard therapy reduced the risk of non-fatal myocardial infarction (MI) (HR 0.84; 95% CI 0.75-0.94) with no difference in the risk of major adverse cardiovascular events (HR 0.97; 95% CI 0.92-1.03) and other adverse cardiovascular outcomes. Intensive versus standard therapy reduced the risk of retinopathy (HR 0.85; 0.78-0.93), nephropathy (HR 0.71; 0.58-0.87) and composite microvascular outcomes (HR 0.88; 0.77-1.00). Meta-regression analyses showed modest evidence of inverse linear relationships between HbA1c reduction and the outcomes of major adverse cardiovascular events, non-fatal MI, stroke and retinopathy, but these were not statistically significant.

CONCLUSIONS

In people with T2D, intensive glucose control was associated with a reduced risk of non-fatal MI and several microvascular outcomes, particularly retinopathy and nephropathy. The lack of an effect of intensive glucose-lowering on most macrovascular outcomes calls for a more comprehensive approach to managing cardiovascular risk factors alongside glycaemic control.

Effect of multidisciplinary care on diabetic kidney disease: a retrospective cohort study

BACKGROUND

Diabetic kidney disease (DKD) is the most common disease among patients requiring dialysis for the first time in Japan. Multidisciplinary care (MDC) may prevent the progression of kidney failure. However, the effectiveness and timing of MDC to preserve kidney function in patients with DKD is unclear. Therefore, the aim of this study was to investigate whether MDC for patients with DKD affects the preservation of kidney function as well as the timing of MDC in clinical practice.

METHODS

In this retrospective cohort study, we identified patients with type 2 diabetes mellitus and DKD from April 2012 to January 2020 using a nationwide Japanese healthcare record database. The fee code for medical guidance to prevent dialysis in patients with diabetes was used to distinguish between the MDC and non-MDC groups. The primary outcome was a 40% decline in the estimated glomerular filtration rate, and secondary outcomes were death, hospitalization, permanent dialysis, kidney failure with replacement therapy, and emergency temporary catheterization. Propensity score matching was performed, and Kaplan-Meier and multivariable Cox regression analyses were performed.

RESULTS

Overall, 9,804 eligible patients met the inclusion criteria, of whom 5,614 were matched for the main analysis: 1,039 in the MDC group, and 4,575 in the non-MDC group. The primary outcome did not differ between the groups (hazard ratio: 1.18, [95% confidence interval: 0.99-1.41], P = 0.07). The groups also did not differ in terms of the secondary outcomes. Most patients with DKD received their first MDC guidance within 1 month of diagnosis, but most received guidance only once per year.

CONCLUSIONS

Although we could not demonstrate the effectiveness of MDC on kidney function in patients with DKD, we clarified the characteristics of such patients assigned the fee code for medical guidance to prevent dialysis related to diabetes.

Causes of In-Hospital Death and Pharmaceutical Associations with Age of Death during a 10-Year Period (2011-2020) in Individuals with and without Diabetes at a Japanese Community General Hospital

Since diabetes and its complications have been thought to exaggerate cardiorenal disease, resulting in a short lifespan, we investigated causes of death and lifespans in individuals with and without diabetes at a Japanese community general hospital during the period from 2011 to 2020. Causes of death and age of death in individuals with and those without diabetes were compared, and associations between medications used and age of death were statistically analyzed. A total of 2326 deaths were recorded during the 10-year period. There was no significant difference between the mean ages of death in individuals with and those without diabetes. Diabetic individuals had higher rates of hepato-pancreatic cancer and cardio-renal failure as causes of death. The prescription rates of antihypertensives, antiplatelets, and statins in diabetic individuals were larger than those in non-diabetic individuals. Furthermore, the use of sulfonyl urea or glinides and insulin was independently and inversely associated with the age of death. In conclusion, individuals with diabetes were treated with comprehensive pharmaceutical interventions and had life spans comparable to those of individuals without diabetes. This study's discovery of an inverse relationship between the use of insulin secretagogues or insulin and the age of death suggests that the prevention of life-threatening hypoglycemia is crucial for individuals with diabetes.

Effect of Lipid-Lowering Drugs on Renal and Cardiovascular Outcomes in Patients with Chronic Kidney Disease and Dyslipidemia: A Retrospective Cohort Study

The effects of lipid-lowering drugs (LLDs) on cardiovascular and renal outcomes in patients with advanced chronic kidney disease (CKD) and dyslipidemia are not completely understood. We conducted a retrospective cohort study to evaluate the effect of LLDs on end-stage kidney disease (ESKD), major adverse cardiovascular events (MACEs), and mortality in adult patients with CKD stage 3b, 4, or 5, and dyslipidemia. Participants were recruited between January 1, 2008, and December 31, 2018, and classified as LLD or non-LLD users; the final follow-up date was December 31, 2020. The primary outcome was time to ESKD or death due to renal failure. Sub-distribution hazard regression models adjusted for multivariables, including time-varying lipid profile covariates, were used for the analysis. Among the 6,740 participants, 4,280 patients with CKD and dyslipidemia, including 872 using LLDs and 3,408 not using LLDs, completed the primary analysis. The multivariable analyses showed that LLD users had a significantly lower risk of time to the composite renal outcome (adjusted hazard ratio [aHR], 0.76, 95% confidence interval [CI], 0.65-0.89), and MACE incidence (aHR, 0.75, 95% CI, 0.62-0.93) than did non-LLD users. After adjusting for time-varying covariates of the lipid profile, there was a significant difference in the composite renal outcome (aHR, 0.78, 95% CI, 0.65-0.93) and MACEs (aHR, 0.77, 95% CI, 0.60-0.98). Among adult patients with advanced CKD and dyslipidemia, LLD users had a significantly lower risk of composite renal outcomes and MACEs than non-LLD users. In addition to reducing lipid profile, the use of LLD is associated with renal and cardiovascular protective effects.

The Effect of Medical Cooperation in the CKD Patients: 10-Year Multicenter Cohort Study

Introduction: While chronic kidney disease (CKD) is one of the most important contributors to mortality from non-communicable diseases, the number of nephrologists is limited worldwide. Medical cooperation is a system of cooperation between primary care physicians and nephrological institutions, consisting of nephrologists and multidisciplinary care teams. Although it has been reported that multidisciplinary care teams contribute to the prevention of worsening renal functions and cardiovascular events, there are few studies on the effect of a medical cooperation system. Methods: We aimed to evaluate the effect of medical cooperation on all-cause mortality and renal prognosis in patients with CKD. One hundred and sixty-eight patients who visited the one hundred and sixty-three clinics and seven general hospitals of Okayama city were recruited between December 2009 and September 2016, and one hundred twenty-three patients were classified into a medical cooperation group. The outcome was defined as the incidence of all-cause mortality, or renal composite outcome (end-stage renal disease or 50% eGFR decline). We evaluated the effects on renal composite outcome and pre-ESRD mortality while incorporating the competing risk for the alternate outcome into a Fine–Gray subdistribution hazard model. Results: The medical cooperation group had more patients with glomerulonephritis (35.0% vs. 2.2%) and less nephrosclerosis (35.0% vs. 64.5%) than the primary care group. Throughout the follow-up period of 5.59 ± 2.78 years, 23 participants (13.7%) died, 41 participants (24.4%) reached 50% decline in eGFR, and 37 participants (22.0%) developed end-stage renal disease (ESRD). All-cause mortality was significantly reduced by medical cooperation (sHR 0.297, 95% CI 0.105–0.835, p = 0.021). However, there was a significant association between medical cooperation and CKD progression (sHR 3.069, 95% CI 1.225–7.687, p = 0.017). Conclusion: We evaluated mortality and ESRD using a CKD cohort with a long-term observation period and concluded that medical cooperation might be expected to influence the quality of medical care in the patients with CKD.

Intensified Multifactorial Intervention in Patients with Type 2 Diabetes Mellitus

In the management of diabetes mellitus, one of the most important goals is to prevent its micro- and macrovascular complications, and to that end, multifactorial intervention is widely recommended. Intensified multifactorial intervention with pharmacotherapy for associated risk factors, alongside lifestyle modification, was first shown to be efficacious in patients with microalbuminuria (Steno-2 study), then in those with less advanced microvascular complications (the Anglo-Danish-Dutch Study of Intensive Treatment In People with Screen Detected Diabetes in Primary Care [ADDITION]-Europe and the Japan Diabetes Optimal Treatment study for 3 major risk factors of cardiovascular diseases [J-DOIT3]), and in those with advanced microvascular complications (the Nephropathy In Diabetes-Type 2 [NID-2] study and Diabetic Nephropathy Remission and Regression Team Trial in Japan [DNETT-Japan]). Thus far, multifactorial intervention led to a reduction in cardiovascular and renal events, albeit not necessarily significant. It should be noted that not only baseline characteristics but also the control status of the risk factors and event rates during intervention among the patients widely varied from one trial to the next. Further evidence is needed for the efficacy of multifactorial intervention in a longer duration and in younger or elderly patients. Moreover, now that new classes of antidiabetic drugs are available, it should be addressed whether strict and safe glycemic control, alongside control of other risk factors, could lead to further risk reductions in micro- and macrovascular complications, thereby decreasing all-cause mortality in patients with type 2 diabetes mellitus.

Altered dietary salt intake for preventing diabetic kidney disease and its progression

BACKGROUND

There is strong evidence that our current consumption of salt is a major factor in the development of increased blood pressure (BP) and that a reduction in our salt intake lowers BP, whether BP levels are normal or raised initially. Effective control of BP in people with diabetes lowers the risk of strokes, heart attacks and heart failure and slows the progression of chronic kidney disease (CKD) in people with diabetes. This is an update of a review first published in 2010.

OBJECTIVES

To evaluate the effect of altered salt intake on BP and markers of cardiovascular disease and of CKD in people with diabetes.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 31 March 2022 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register were identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of altered salt intake in individuals with type 1 and type 2 diabetes. Studies were included when there was a difference between low and high sodium intakes of at least 34 mmol/day.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies and resolved differences by discussion. We calculated mean effect sizes as mean difference (MD) and 95% confidence intervals (CI) using the random-effects model. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

Thirteen RCTs (313 participants), including 21 comparisons (studies), met our inclusion criteria. One RCT (two studies) was added to this review update. Participants included 99 individuals with type 1 diabetes and 214 individuals with type 2 diabetes. Two RCTs (four studies) included some participants with reduced overall kidney function. The remaining studies either reported that participants with reduced glomerular filtration rate (GFR) were excluded from the study or only included participants with microalbuminuria and normal GFR. Five studies used a parallel study design, and 16 used a cross-over design. Studies were at high risk of bias for most criteria. Random sequence generation and allocation concealment were adequate in only three and two studies, respectively. One study was at low risk of bias for blinding of participants and outcome assessment, but no studies were at low risk for selective reporting. Twelve studies reported non-commercial funding sources, three reported conflicts of interest, and eight reported adequate washout between interventions in cross-over studies. The median net reduction in 24-hour urine sodium excretion (24-hour UNa) in seven long-term studies (treatment duration four to 12 weeks) was 76 mmol (range 51 to 124 mmol), and in 10 short-term studies (treatment duration five to seven days) was 187 mmol (range 86 to 337 mmol). Data were only available graphically in four studies. In long-term studies, reduced sodium intake may lower systolic BP (SBP) by 6.15 mm Hg (7 studies: 95% CI -9.27 to -3.03; I² = 12%), diastolic BP (DBP) by 3.41 mm Hg (7 studies: 95% CI -5.56 to -1.27; I² = 41%) and mean arterial pressure (MAP) by 4.60 mm Hg (4 studies: 95% CI -7.26 to -1.94; I² = 28%). In short-term studies, low sodium intake may reduce SBP by 8.43 mm Hg (5 studies: 95% CI -14.37 to -2.48; I² = 88%), DBP by 2.95 mm Hg (5 studies: 95% CI -4.96 to -0.94; I² = 70%) and MAP by 2.37 mm Hg (9 studies: 95% CI -4.75 to -0.01; I² = 65%). There was considerable heterogeneity in most analyses but particularly among short-term studies. All analyses were considered to be of low certainty evidence. SBP, DBP and MAP reductions may not differ between hypertensive and normotensive participants or between individuals with type 1 or type 2 diabetes. In hypertensive participants, SBP, DBP and MAP may be reduced by 6.45, 3.15 and 4.88 mm Hg, respectively, while in normotensive participants, they may be reduced by 8.43, 2.95 and 2.15 mm Hg, respectively (all low certainty evidence). SBP, DBP and MAP may be reduced by 7.35, 3.04 and 4.30 mm Hg, respectively, in participants with type 2 diabetes and by 7.35, 3.20, and 0.08 mm Hg, respectively, in participants with type 1 diabetes (all low certainty evidence). Eight studies provided measures of urinary protein excretion before and after salt restriction; four reported a reduction in urinary albumin excretion with salt restriction. Pooled analyses showed no changes in GFR (12 studies: MD -1.87 mL/min/1.73 m², 95% CI -5.05 to 1.31; I² = 32%) or HbA1c (6 studies: MD -0.62, 95% CI -1.49 to 0.26; I² = 95%) with salt restriction (low certainty evidence). Body weight was reduced in studies lasting one to two weeks but not in studies lasting for longer periods (low certainty evidence). Adverse effects were reported in only one study; 11% and 21% developed postural hypotension on the low-salt diet and the low-salt diet combined with hydrochlorothiazide, respectively.

AUTHORS' CONCLUSIONS

This systematic review shows an important reduction in SBP and DBP in people with diabetes with normal GFR during short periods of salt restriction, similar to that obtained with single drug therapy for hypertension. These data support the international recommendations that people with diabetes with or without hypertension or evidence of kidney disease should reduce salt intake to less than 5 g/day (2 g sodium).

Current status of diabetic kidney disease and latest trends in management

Diabetic kidney disease (DKD) is one of the major microvascular complications of diabetes and is leading cause of end-stage renal disease (ESRD) and one of major risk factors of cardiovascular disease (CVD).

Impact of salt intake on urinary albumin excretion in patients with type 2 diabetic nephropathy: a retrospective cohort study based on a generalized additive model

Diabetic kidney disease is an important and common cause of end-stage renal disease. Measurement of urinary albumin excretion (UAE) requires the diagnosis of the stage of diabetic nephropathy and the prognosis of renal function. We aimed to analyze the impact of lifestyle modification on UAE in patients with stage 2 and 3 type 2 diabetic nephropathy who received comprehensive medical care, using a generalized additive model (GAM), an explanatory machine learning model. In this retrospective observational study, we used changes in HbA1c, systolic blood pressure (SBP), and diastolic blood pressure (DBP) levels; body mass index (BMI); and daily salt intake as factors contributing to changes in UAE. In total, 269 patients with type 2 diabetic nephropathy were enrolled (stage 2, 217 patients; stage 3, 52 patients). The rankings that contributed to changes in UAE over 6 months by permutation importance were the changes in daily salt intake, HbA1c, SBP, DBP, and BMI. GAM, which predicts the change in UAE, showed that with increase in the changes in salt intake, SBP, and HbA1c, the delta UAE tended to increase. Salt intake was the most contributory factor for the changes in UAE, and daily salt intake was the best lifestyle factor to explain the changes in UAE. Strict control of salt intake may have beneficial effects on improving UAE in patients with stage 2 and 3 diabetic nephropathy.

The Association of Postprandial Triglyceride Variability with Renal Dysfunction and Microalbuminuria in Patients with Type 2 Diabetic Mellitus: A Retrospective and Observational Study

OBJECTIVE

We examined whether or not day-to-day variations in lipid profiles, especially triglyceride (TG) variability, were associated with the exacerbation of diabetic kidney disease.

METHODS

We conducted a retrospective and observational study. First, 527 patients with type 2 diabetes mellitus (DM) who had had their estimated glomerular filtration rate (eGFR) checked every 6 months since 2012 for over 5 years were registered. Variability in postprandial TG was determined using the standard deviation (SD), SD adjusted (Adj-SD) for the number of measurements, and maximum minus minimum difference (MMD) during the first three years of follow-up. The endpoint was a ≥40% decline from baseline in the eGFR, initiation of dialysis or death. Next, 181 patients who had no micro- or macroalbuminuria in February 2013 were selected from among the 527 patients for an analysis. The endpoint was the incidence of microalbuminuria, initiation of dialysis, or death.

RESULTS

Among the 527 participants, 110 reached a ≥40% decline from baseline in the eGFR or death. The renal survival was lower in the higher-SD, higher-Adj-SD, and higher-MMD groups than in the lower-SD, lower-Adj-SD, and lower-MMD groups, respectively (log-rank test p = 0.0073, 0.0059, and 0.0195, respectively). A lower SD, lower Adj-SD, and lower MMD were significantly associated with the renal survival in the adjusted model (hazard ratio, 1.62, 1.66, 1.59; 95% confidence intervals, 1.05-2.53, 1.08-2.58, 1.04-2.47, respectively). Next, among 181 participants, 108 developed microalbuminuria or death. The nonincidence of microalbuminuria was lower in the higher-SD, higher-Adj-SD, and higher-MMD groups than in the lower-SD, lower-Adj-SD, and lower-MMD groups, respectively (log-rank test p = 0.0241, 0.0352, and 0.0474, respectively).

CONCLUSIONS

Postprandial TG variability is a novel risk factor for eGFR decline and the incidence of microalbuminuria in patients with type 2 DM.

Treatments for Chronic Kidney Disease: A Systematic Literature Review of Randomized Controlled Trials

Delaying disease progression and reducing the risk of mortality are key goals in the treatment of chronic kidney disease (CKD). New drug classes to augment renin-angiotensin-aldosterone system (RAAS) inhibitors as the standard of care have scarcely met their primary endpoints until recently. This systematic literature review explored treatments evaluated in patients with CKD since 1990 to understand what contemporary data add to the treatment landscape. Eighty-nine clinical trials were identified that had enrolled patients with estimated glomerular filtration rate 13.9-102.8 mL/min/1.73 m2 and urinary albumin-to-creatinine ratio (UACR) 29.9-2911.0 mg/g, with (75.5%) and without (20.6%) type 2 diabetes (T2D). Clinically objective outcomes of kidney failure and all-cause mortality (ACM) were reported in 32 and 64 trials, respectively. Significant reductions (P < 0.05) in the risk of kidney failure were observed in seven trials: five small trials published before 2008 had evaluated the RAAS inhibitors losartan, benazepril, or ramipril in patients with (n = 751) or without (n = 84-436) T2D; two larger trials (n = 2152-2202) published onwards of 2019 had evaluated the sodium-glucose co-transporter 2 (SGLT2) inhibitors canagliflozin (in patients with T2D and UACR > 300-5000 mg/g) and dapagliflozin (in patients with or without T2D and UACR 200-5000 mg/g) added to a background of RAAS inhibition. Significant reductions in ACM were observed with dapagliflozin in the DAPA-CKD trial. Contemporary data therefore suggest that augmenting RAAS inhibitors with new drug classes has the potential to improve clinical outcomes in a broad range of patients with CKD.

Improvement of Diabetes Mellitus After Colorectal Cancer Surgery: A Retrospective Study of Predictive Factors For Type 2 Diabetes Mellitus Remission and Overall Survival

PURPOSE

The purpose of the current study was to evaluate the impact of colorectal cancer (CRC) surgery on type 2 diabetes mellitus (T2DM) and to analyze the change in T2DM on overall survival after CRC surgery.

METHODS

Patients who underwent CRC surgery were retrospectively enrolled from January 2013 to December 2019. The status of T2DM pre- and 1-year after CRC surgery was recorded, and predictive factors for T2DM remission and overall survival were analyzed.

RESULTS

A total of 296 patients were included in this study. Thirty-eight patients experienced remission of T2DM 1 year after CRC surgery, and the remission rate was 12.8%. Weight loss was significantly higher in the T2DM remission group (p = 0.038), and the T2DM duration was significantly shorter in the T2DM remission group (p = 0.015). In the multivariate logistic regression analysis, higher weight loss (p = 0.046, odds ratio = 1.060, 95% CI = 1.001-1.122) and shorter T2DM duration (p = 0.019, odds ratio = 1007, 95% CI = 1.001-1.014) were predictive factors for remission of T2DM. Furthermore, in multivariate Cox regression analysis, lower TNM stage (p = 0.000, odds ratio = 2.147, 95% CI = 1.474-3.128) and T2DM remission (p = 0.033, odds ratio = 2.999, 95% CI = 1.091-8.243) were the predictive factors for better overall survival.

CONCLUSION

Patients with concurrent CRC and T2DM had a 12.8% remission 1 year after CRC surgery. Higher weight loss and shorter T2DM duration contributed to T2DM remission, and patients with T2DM remission could improve in terms of their overall survival.

Recent evidence in the etiology and treatment for diabetic kidney disease

Etiology and therapeutic targets of diabetic nephropathy.

Renoprotective Effects of DPP-4 Inhibitors

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease (ESRD) worldwide. Dipeptidyl peptidase (DPP)-4 inhibitors are widely used in the treatment of patients with type 2 diabetes (T2D). DPP-4 inhibitors reduce glucose levels by inhibiting degradation of incretins. DPP-4 is a ubiquitous protein with exopeptidase activity that exists in cell membrane-bound and soluble forms. It has been shown that an increased renal DPP-4 activity is associated with the development of DKD. A series of clinical and experimental studies showed that DPP-4 inhibitors have beneficial effects on DKD, independent of their glucose-lowering abilities, which are mediated by anti-fibrotic, anti-inflammatory, and anti-oxidative stress properties. In this review article, we highlight the current understanding of the clinical efficacy and the mechanisms underlying renoprotection by DPP-4 inhibitors under diabetic conditions.