Changes in the estimated glomerular filtration rate and predictors of the renal prognosis in Japanese patients with type 2 diabetes: A retrospective study during the 12 months after the initiation of tofogliflozin.

BACKGROUND: The changes in the estimated glomerular filtration rate (eGFR) and predictors of the renal prognosis were retrospectively assessed over the 12 months after the initiation of tofogliflozin, which has the shortest half-life among sodium-glucose cotransporter 2 (SGLT2) inhibitors, in Japanese patients with type 2 diabetes and renal impairment. METHODS: In total, 158 patients treated with tofogliflozin between 2019 and 2021 were studied as the safety analysis set. One hundred and thirty subjects whose medication was continued over 12 months were investigated as the full analysis set. The subjects were divided into two groups based on the eGFR: normal- (eGFR ≥60 mL/min/1.73 m2, n = 87) and low- (eGFR <60 mL/min/1.73 m2, n = 43) eGFR groups. RESULTS: The body weight, blood pressure, urinary protein excretion, and serum uric acid concentration decreased from baseline in both eGFR groups while the hemoglobin level increased. The eGFR did not significantly differ over time, except for the initial dip (-4.3±9.6 mL/min/1.73 m2 in the normal-eGFR group and -1.5±5.3 mL/min/1.73 m2 in the low-eGFR group). The change in the eGFR at 12 months after the initiation of tofogliflozin was -1.9±9.0 mL/min/1.73 m2 and 0.2±6.0 mL/min/1.73 m2 in the normal- and low-eGFR group, respectively. In the normal-eGFR group, the change in the eGFR showed a significant negative correlation with the HbA1c and eGFR at baseline, according to a multiple regression analysis. In the low-eGFR group, the change in the eGFR showed a significant negative correlation with urate-lowering agent use. The frequencies of adverse events specific for SGLT2 inhibitors were not significantly different between the normal- and low-eGFR groups. CONCLUSIONS: Tofogliflozin may preserve renal function in the medium term in patients with type 2 diabetes and kidney impairment without an increase in specific adverse events.

Prevalence, correlates and in-hospital outcomes of kidney dysfunction in hospitalized patients with heart failure in Buea-Cameroon.

BACKGROUND: Kidney dysfunction is common in patients with heart failure (HF) and has been associated with poor outcomes. This study aimed to determine the prevalence, correlates, and prognosis of kidney dysfunction in patients with HF in Cameroon, an understudied population. METHODS: We conducted a cross-sectional study in consecutive patients hospitalized with HF between June 2016 and November 2017 in the Buea Regional Hospital, Cameroon. Kidney dysfunction was defined as an estimated glomerular filtration rate < 60 ml/min/1.73m2. Prognostic outcomes included death and prolonged hospital stay (> 7 days). We also performed a sensitivity analysis excluding racial considerations. RESULTS: Seventy four patients (86.1% of those eligible) were included. Their median age was 60 (interquartile range: 44-72) years and 46.0% (n = 34) were males. Half of patients (n = 37) had kidney dysfunction. Correlates of kidney dysfunction included previous diagnosis of HF (adjusted odds ratio [aOR]4.3, 95% CI: 1.1-17.5) and left ventricular hypertrophy (aOR3.4, 95% CI: 1.1-9.9). Thirty-six (48.9%) had prolonged hospital stay, and seven (9.5%) patients died in hospital. Kidney dysfunction was not associated with in-hospital death (aOR 0.4, 95% CI: 0.1-2) nor prolonged hospital stay (aOR 2.04, 0.8-5.3). In sensitivity analysis (excluding racial consideration), factors associated with Kidney dysfunction in HF were; anemia (aOR: 3.0, 95% CI: 1.1-8.5), chronic heart failure (aOR: 4.7, 95% CI: 0.9-24.6), heart rate on admission < 90 bpm (aOR: 3.4, 95% CI: 1.1-9.1), left atrial dilation (aOR: 3.2, 95% CI: 1.04-10), and hypertensive heart disease (aOR: 3.1, 95% CI: 1.2-8.4). Kidney dysfunction in HF was associated with hospital stay > 7 days (OR: 2.6, 95% CI: 1-6.8). CONCLUSION: Moderate-to-severe kidney dysfunction was seen in half of the patients hospitalized with HF in our setting, and this was associated with a previous diagnosis of HF and left ventricular hypertrophy. Kidney dysfunction might not be the main driver of poor HF outcomes in this population. In sensitivity analysis, this was associated with anemia, chronic heart failure, heart rate on admission less than 90 bpm, left atrial dilatation, and hypertensive heart disease. Kidney dysfunction was associated with hospital stay > 7 days.

Recent Clinical Trials Insights into the Treatment of Primary Membranous Nephropathy.

Immunosuppressive therapy is mandatory for primary membranous nephropathy with persistent nephrotic proteinuria or anti-phospholipase A2 receptor antibodies, reduced kidney function, or another risk factor for progression. Rituximab has demonstrated efficacy for proteinuria remission compared with renin-angiotensin system blockade or cyclosporine in two well-powered randomized controlled trials. More recently, STARMEN showed that alternating glucocorticoid-cyclophosphamide is superior to sequential tacrolimus-rituximab for proteinuria remission, although it was associated with a higher risk of non-serious adverse events. However, sequential tacrolimus-rituximab involved delayed lower dose rituximab and was the worst-performing rituximab regimen among those tested in randomized clinical trials. The RI-CYCLO pilot study did not demonstrate superiority of glucocorticoid-cyclophosphamide over rituximab and found no difference in adverse events. Overall, STARMEN and RI-CYCLO confirmed the efficacy of glucocorticoid-cyclophosphamide in patients with high-risk membranous nephropathy and the role of rituximab as a valid alternative. However, none of the trials tested an optimized rituximab protocol involving a second rituximab cycle before declaring treatment failure. Calcineurin inhibitors should be considered third-line drugs and sequential use of calcineurin inhibitor rituximab did not add over rituximab-only regimens. We critically review recent randomized controlled trials, propose a research agenda, and call for multinational pragmatic trials that enroll patients at referral centers to address unmet research needs.

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.

Blood and Urine Biomarkers Predicting Worsening Kidney Function in Patients with Type 2 Diabetes Post-Acute Coronary Syndrome: An Analysis from the EXAMINE Trial.

INTRODUCTION: Worsening kidney function (WKF) is frequent among patients with type 2 diabetes (T2D) and a recent acute coronary syndrome (ACS) and is associated with a poor prognosis. An accurate prediction of WKF is clinically important. AIMS: Using data from the Cardiovascular Outcomes Study of Alogliptin in Patients with Type 2 Diabetes and Acute Coronary Syndrome trial including patients with T2D and a recent ACS, and a large biomarker panel incorporating proteins measured both in blood and urine, we aim to determine those with best performance for WKF prediction. METHODS: WKF was defined as a ≥40% estimated glomerular filtration rate (eGFR) drop from baseline, eGFR <15 mL/min, or dialysis. Mixed-effects and time-updated Cox models were used. RESULTS: 5,131 patients were included from whom 222 (4.3%) developed at least one WKF episode over a median follow-up of 18 months. Patients who developed WKF were more frequently women, had longer diabetes duration, a more frequent heart failure history, higher anemia prevalence, and impaired kidney function. In multivariable models including all variables (clinical and biomarkers) independently associated with WKF with a p value ≤0.0001, blood kidney injury molecule 1 (KIM-1) was (by far) the variable with strongest WKF association, followed by anemia. KIM-1 alone provided good discrimination for WKF prediction (area under the curve = 0.73). Patients in the high KIM-1-derived risk tertile had a 6.7-fold higher risk of any WKF than patients classified as low risk. In time-updated Cox models, the occurrence of WKF was independently associated with a higher risk of death: adjusted hazard ratio = 4.93 (3.06-7.96), p value <0.0001. CONCLUSION: Blood KIM-1 was the biomarker with the strongest association with WKF. The occurrence of WKF was independently associated with a higher risk of subsequent cardiovascular events and mortality.

Decreased estimated glomerular filtration rate predicts long-term recurrence after catheter ablation of atrial fibrillation in mild to moderate renal insufficiency.

BACKGROUND: Catheter ablation is an established therapy for atrial fibrillation (AF), but recurrence after ablation remains a great challenge. Additionally, little is known about the effect of renal function on the efficiency of AF ablation. This study aimed to evaluate the predictors of the prognosis of catheter ablation for AF, especially the effect of renal function. METHODS: A total of 306 drug-refractory symptomatic patients with AF who underwent first-time catheter ablation were enrolled in the present study. Individuals underwent circumferential pulmonary vein isolation for paroxysmal AF and stepwise ablation for persistent AF. RESULTS: The follow-up time was 27.2 ± 19.5 months, 202 patients (66.01%) were free of atrial tachyarrhythmia (non-recurrence group), and the other 104 patients experienced recurrence (recurrence group). The recurrence group had a larger left atrial diameter (LAD) and left atrial volume (LAV), a higher LAV index (LAVI) (both, p < 0.01), and a lower estimated glomerular filtration rate (eGFR) (53.5 ± 14.4 vs. 65.5 ± 13.3 ml/min/1.732, p < 0.001) and creatinine clearance rate (CCr) (85.2 ± 26.1 vs. 101.5 ± 29.4 ml/min, p < 0.05). Multivariate logistic regression indicated both eGFR (p = 0.002) and LAVI (p < 0.001) as independent associated factors for long-term recurrence after single catheter ablation; multivariate Cox proportional hazard regression with backward feature selection identified both eGFR (HR: 0.93, 95% CI: 0.91-0.95, p < 0.001) and LAVI (HR: 1.32, 95% CI: 1.25-1.40, p < 0.001) as independent prognostic factors for recurrence when adjusting other clinical variables. CONCLUSIONS: Decreased eGFR and elevated LAVI may facilitate the long-term recurrence of atrial tachyarrhythmia after catheter ablation for AF.

Mineralocorticoid receptor antagonists use in patients with heart failure and impaired renal function.

AIMS: Impaired renal function is a major contributor to the low proportion of mineralocorticoid receptor antagonist (MRA) treatment in patients with heart failure with reduced ejection fraction (HFrEF). Our aims were to investigate the impact of MRA treatment on all-cause mortality and worsening renal function (WRF) in patients with HFrEF and moderately impaired renal function. METHODS: Retrospective data between 2010-2018 on HFrEF patients from a single-centre hospital with estimated glomerular renal function (eGFR) < 60 ml/min/1.73 m2 were analysed. WRF was defined as a decline of by eGFR ≥ 20%. RESULTS: 416 patients were included, 131 patients on MRA and 285 without MRA, mean age was 77 years (SD ± 9) and 82 years (SD ± 9), respectively. Median follow-up was 2 years. 128 patients (32%) experienced WRF, 25% in the MRA group and 30% in patients without MRA (p = 0.293). In multivariable analysis, hospitalization for heart failure and systolic blood pressure were associated with WRF (p = 0.015 and p = <0.001), but not use of MRA (p = 0.421). MRA treatment had no impact on the risk of adjusted all-cause mortality (HR 0.93; 95% CI, 0.66-1.32 p = 0.685). WRF was associated with increased adjusted risk of all-cause mortality (HR 1.43; 95% CI, 1.07-1.89 p = 0.014). Use of MRA did not increase the adjusted overall risk of mortality even when experiencing WRF (HR 1.15; 95% CI, 0.81-1.63 p = 0.422). CONCLUSION: In this cohort of elderly HFrEF patients with moderately impaired renal function, MRA did not increase risk for WRF or all-cause mortality.

Commentary on Intraglumerular dysfunction predicts kidney failure in the type 2 diabetes.

The key physiological parameters that determine glomerular filtration rate levels are renal plasma flow, filtration fraction, intraglomerular pressure, and balance between afferent and efferent glomerular arteriolar resistance. The evaluation of the balance between afferent and efferent glomerular arteriolar resistance might be useful for the classification of diabetic kidney disease.

Effect of Vitamin D Supplementation on Kidney Function in Adults with Prediabetes: A Secondary Analysis of a Randomized Trial.

BACKGROUND AND OBJECTIVES: Low serum 25-hydroxyvitamin D (25[OH]D) concentration has been associated with higher levels of proteinuria and lower levels of eGFR in observational studies. In the Vitamin D and Type 2 Diabetes (D2d) study, we investigated the effect of vitamin D supplementation on kidney outcomes in a population with prediabetes. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Overweight/obese adults with high risk for type 2 diabetes (defined by meeting two of three glycemic criteria for prediabetes) were randomized to vitamin D3 4000 IU per day versus placebo. Median duration of treatment was 2.9 years (interquartile range 2.0-3.5 years). Kidney outcomes included (1) worsening in Kidney Disease: Improving Global Outcomes (KDIGO ) risk score (low, moderate, high, very high) on two consecutive follow-up visits after the baseline visit and (2) mean changes in eGFR and urine albumin-to-creatinine ratio (UACR). RESULTS: Among 2166 participants (mean age 60 years, body mass index 32 kg/m2, serum 25(OH)D 28 ng/ml, eGFR 87 ml/min per 1.73 m2, UACR 11 mg/g, 79% with hypertension), 10% had moderate, high, or very high KDIGO risk score. Over a median follow-up of 2.9 years, there were 28 cases of KDIGO worsening in the vitamin D group and 30 in the placebo group (hazard ratio, 0.89; 95% confidence interval [95% CI], 0.52 to 1.52]). Mean difference in eGFR from baseline was -1.0 ml/min per 1.73 m2 (95% CI, -1.3 to -0.7) in the vitamin D group and -0.1 ml/min per 1.73 m2 (95% CI, -0.4 to 0.2) in the placebo group; between-group difference was -1.0 ml/min per 1.73 m2 (95% CI, -1.4 to -0.6). Mean difference in UACR was 2.7 mg/g (95% CI, 1.2 to 4.3) in the vitamin D group and 2.0 (95% CI, 0.5 to 3.6) in the placebo group; between-group difference was 0.7 mg/g (95% CI, -1.5 to 2.9). CONCLUSIONS: Among persons with prediabetes, who were not preselected on the basis of serum 25(OH)D concentration, vitamin D supplementation did not affect progression of KDIGO risk scores and did not have a meaningful effect on change in UACR or eGFR.

Renal Cortical Perfusion Estimated in Color Doppler Dynamic Tissue Perfusion Measurement in Patients Treated with Levothyroxine Following Total Thyroidectomy for Resectable Thyroid Cancer Is Independently Associated with Free Thyroxine: A Single-Center Prospective Study.

BACKGROUND The thyroid state significantly influences renal function. However, a direct link between thyroid and kidney dysfunction has not been identified. Thyroid hormones affect cardiac output and vascular resistance, and thus can modify kidney perfusion. This prospective study aimed to test the association between renal cortical perfusion (RCP) estimated in color Doppler sonographic dynamic tissue perfusion measurement (DTPM) with thyroid hormones in 36 patients treated with levothyroxine following total thyroidectomy for resectable thyroid cancer. MATERIAL AND METHODS Blood tests, blood pressure monitoring, and DTPM of the renal cortex were performed. To exclude possible reading errors, the intrarater reliability of the ultrasound perfusion measurement method was estimated. RESULTS The absolute difference between the 2 ultrasound RCP measurements was 5.2±4.4%. RCP correlated significantly with free thyroxine (FT4) (r=0.46; p=0.006) but not with triiodothyronine and thyroid-stimulating hormone. In the adjusted to age backward stepwise multivariable regression analysis model, including estimated glomerular filtration rate, mean arterial pressure, and FT4, only FT4 was independently associated with RCP (R²=0.21; p=0.006). CONCLUSIONS Renal cortical perfusion is independently associated with free thyroxine, which can contribute to renal function abnormalities in the condition of impaired thyroid function. This small prospective study from a single center showed that the renal cortex's color Doppler sonographic dynamic tissue perfusion measurement had very good intraobserver reproducibility.

Predialysis predictors for identifying patients requiring dialysis at a higher glomerular filtration rate.

BACKGROUND: Current evidence suggests that the initiation of maintenance hemodialysis should not be based on a specific glomerular filtration rate (GFR) but on symptoms or signs attributable to kidney disease. However, it is difficult to predict the time point at which overt uremic syndrome develops in individuals. The estimated GFR is poorly correlated with occurrence of uremic symptoms, and some patients require dialysis at a higher eGFR than others. In this case, patients are more likely to be improperly prepared for dialysis. We investigated the predialysis characteristics of patients who require dialysis at a higher eGFR. METHODS: A total of 453 incident dialysis patients being monitored by a nephrologist from January 2013 to December 2018 were included. The predialysis characteristics when eGFR decreased to 20 mL/min/1.73 m2 were obtained. RESULTS: The mean age was 61 years, and 65.7% were men. Overall, the median eGFR at the first dialysis was 5.8 (interquartile range 4.6-7.3) mL/min/1.73 m2 and initiation of dialysis at the first quintile (≥7.8 mL/min/1.73 m2) was defined as 'early initiation of dialysis' Among the predialysis characteristics, heart failure (adjusted odds ratio 3.68; 95% confidence interval, 1.59-8.03), serum albumin <4.0 mg/dL (2.22; 1.30-3.77), blood urea nitrogen (BUN)/creatinine (Cr) ratio >15 mg/mg (1.92, 1.16-3.18), and hyperuricemia (1.84; 1.05-3.23) were independent predictors of early initiation. Diabetes mellitus and the causes of kidney disease were not independent predictors of early initiation. The early initiation group was less likely to initiate dialysis with a permanent vascular access than the late initiation group. CONCLUSIONS: For patients with heart failure, low serum albumin level, high BUN/Cr ratio, or hyperuricemia, clinicians can provide predialysis counseling in advance and consider early creation of vascular access.

Effects of renal impairment on cardiac remodeling and clinical outcomes after myocardial infarction.

How renal function influences post-acute myocardial infarction (AMI) cardiac remodeling and outcomes remains unclear. This study evaluated the impact of levels of renal impairment on drug therapy, echocardiographic parameters, and outcomes in patients with AMI undergoing percutaneous coronary intervention (PCI). A total of 611 patients diagnosed with AMI underwent successful PCI, and two echocardiographic examinations were performed within 1 year after AMI. Patients were categorized according to Group 1: severely impaired estimated glomerular filtration rate (eGFR)<30, Group 2: mildly impaired 30≤eGFR<60, Group 3: potentially at risk 60≤eGFR<90 and normal eGFR≥90 ml/min/1.73 m2. During the 5-year follow-up period, the primary endpoints were cardiovascular mortality and outcomes. Patients with worse renal function (eGFR<30) were older and had a higher prevalence of hypertension and diabetes, but relatively few were smokers or had hyperlipidemia. Despite more patients with lesions of the left anterior descending artery, those with worse renal function received suboptimal guideline-directed medical therapy (GDMT). Notably, patients with worse renal function presented with worse left ventricular function at baseline and subsequent follow-up. Kaplan-Meier analysis revealed increased cardiovascular death, development of heart failure, recurrent AMI and revascularization in patients with worse renal function. Notably, as focusing on patients with ST elevation MI, the similar findings were observed. In multivariable Cox regression, impaired renal function showed the most significant hazard ratio in cardiovascular death. Collectively, in AMI patients receiving PCI, outcome differences are renal function dependent. We found that patients with worse renal function received less GDMT and presented with worse cardiovascular outcomes. These patients require more attention.

Intraglomerular Dysfunction Predicts Kidney Failure in Type 2 Diabetes.

No longitudinal data link intraglomerular hemodynamic dysfunction with end-stage kidney disease (ESKD) in people with type 2 diabetes (T2D). Afferent (RA) and efferent (RE) arteriolar resistance and intraglomerular pressure (PGLO) are not directly measurable in humans but are estimable from glomerular filtration rate (GFR), renal plasma flow (RPF), blood pressure, hematocrit, and plasma oncotic pressure. We examined the association of the RA-to-RE ratio and PGLO with ESKD incidence in 237 Pima Indian individuals with T2D who underwent serial measures of GFR (iothalamate) and RPF (p-aminohippurate). Their association with kidney structural lesions was also examined in a subset of 111 participants. Of the 237 participants (mean age 42 years, diabetes duration 11 years, and GFR 153 mL/min and median urine albumin-to-creatinine ratio 36 mg/g), 69 progressed to ESKD during a median follow-up of 17.5 years. In latent class analysis, distinct trajectories characterized by increasing RA-to-RE ratio (HR 4.60, 95% CI 2.55-8.31) or elevated PGLO followed by a rapid decline (HR 2.96, 95% CI 1.45-6.02) strongly predicted incident ESKD. PGLO (R 2 = 21%, P < 0.0001) and RA-to-RE ratio (R 2 = 15%, P < 0.0001) also correlated with mesangial fractional volume, a structural predictor of DKD progression. In conclusion, intraglomerular hemodynamic parameters associated strongly with incident ESKD and correlated with structural lesions of DKD.