Twenty-Four Hour Blood Pressure Response to Empagliflozin and Its Determinants in Normotensive Non-diabetic Subjects

The Effects of SGLT2 Inhibitors on Blood Pressure and Other Cardiometabolic Risk Factors

Beyond their established hypoglycemic, cardioprotective, and nephroprotective properties, sodium-glucose cotransporters 2 (SGLT2) inhibitors exert other pleiotropic actions on blood pressure levels, body weight, and lipid metabolism. Blood pressure (BP) reduction varies based on the background history, including an effect on systolic, diastolic BP, and 24 h BP measurements. The reduction in body weight between 1 and 2 kg for the first months is caused by a reduction in visceral and subcutaneous fat due to glycosuria and loss of calories. Regarding lipid metabolism, a reduction in triglycerides and an increase in total cholesterol, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) have been reported, although these alterations are small and could provide additional cardiovascular protection. Various pathophysiologic mechanisms have been proposed to explain the above-mentioned pleiotropic actions of SGLT2 inhibitors. Natriuresis, osmotic diuresis, body weight reduction, amelioration of endothelial dysfunction and arterial stiffness, sympathetic tone decrease, and uric acid reduction are among those that have been suggested for BP reduction. Apart from glycosuria and calorie loss, other mechanisms seem to contribute to body weight reduction, such as the beiging of white adipose tissue, while the mechanisms involved in lipid metabolism alterations have not been clearly determined.

Effects of Sodium-Glucose Cotransporter 2 Inhibitors in Diabetic and Non-Diabetic Patients with Advanced Chronic Kidney Disease in Peritoneal Dialysis on Residual Kidney Function: In Real-World Data

Background and Objectives: Peritoneal dialysis (PD) is a renal replacement therapy modality in which the dialysis dose can be individually adapted according to the patients' residual kidney function (RKF). RKF is a crucial factor for technique and patient survival. Pharmacological strategies aimed at slowing the loss of RKF in patients on PD are limited. Therefore, we aimed to assess the potential effects and safety of sodium-glucose cotransporter 2 (SGLT-2) inhibitors on the preservation of RKF in patients with and without type 2 diabetes mellitus (T2DM) on PD during an average follow-up of 6 months. Materials and Methods: In this retrospective observational, single-center study on real-world data, we included patients from the Peritoneal Dialysis Unit of the Hospital General Universitario de Ciudad Real, who started treatment with SGLT-2 inhibitors during the period from December 2022 to December 2023. Data on analytical and clinical parameters, RKF, and peritoneal membrane transport function were retrospectively collected at months 0, 3, and 6. Results: Out of 31 patients in our unit, 16 prevalent patients initiated treatment with SGLT-2 inhibitors (13 empagliflozin and 3 dapagliflozin). A total of 62.5% were male and the mean age was 67.3 years. The baseline peritoneal ultrafiltration was higher in the non-diabetic patient (NDMP) group than in the diabetic patient (DMP) group. However, the residual diuresis volume, 24 h residual renal clearance rate of urea in urine, and 24 h proteinuria were higher in the DMP group than in the NDMP group. At the sixth month, patients in both groups preserved RKF and diuresis, with a trend towards a non-significant reduction in proteinuria and blood pressure. Only two patients of the DMP group presented adverse effects. Conclusions: The use of SGLT-2 inhibitors in our sample of patients with and without T2DM on PD appears to be safe and effective to preserve RKF.

Sodium-Glucose Co-Transporter 2 Inhibitors: Mechanism of Action and Efficacy in Non-Diabetic Kidney Disease from Bench to Bed-Side

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are currently available for the management of type 2 diabetes mellitus. SGLT2i acts by inhibiting renal SGLT2, thereby increasing glucosuria and lowering serum glucose. Recent trials are emerging supporting a role for SGLT2i irrespective of the diabetic status pointing towards that SGLT2i have other mechanisms of actions beyond blood sugar control. In this review, we will shed light on the role of this group of medications that act as SGLT2i in non-diabetics focusing on pre-clinical and clinical data highlighting the mechanism of renoprotection and effects of SGLT2i in the non-diabetic kidneys.

The urine-to-plasma urea concentration ratio is associated with eGFR and eGFR decline over time in a population cohort

BACKGROUND

Evaluation of renal function and of factors associated with its decline are important public health issues. Besides markers of glomerular function [e.g. glomerular filtration rate (GFR)], those of tubular functions are rarely evaluated. Urea, the most abundant urinary solute, is markedly concentrated in urine when compared with plasma. We explored the urine-to-plasma ratio of urea concentrations (U/P urea ratio) as a marker of tubular functions.

METHODS

We evaluated the relationship of the U/P urea ratio with eGFR at baseline in 1043 participants (48 ± 17 years) from the Swiss Kidney Project on Genes in Hypertension (SKIPOGH) population-based cohort, using mixed regression. In 898 participants, we assessed the relation between U/P urea ratio and renal function decline between two study waves 3 years apart. We studied U/P ratios for osmolarity, Na, K and uric acid for comparison.

RESULTS

In a transversal study at baseline, estimated GFR (eGFR) was positively associated with U/P-urea ratio [βscaled = 0.08, 95% CI (0.04; 0.13)] but not with the U/P ratio of osmolarity. Considering separately participants with renal function >90 or ≤90 mL/min × 1.73 m2, this association was observed only in those with reduced renal function. In the longitudinal study, eGFR declined at a mean rate of 1.2 mL/min per year. A significant association was observed between baseline U/P urea ratio and eGFR decline [βscaled = 0.08, 95% CI (0.01; 0.15)]. A lower baseline U/P urea ratio was associated with a greater eGFR decline.

CONCLUSION

This study provides evidence that the U/P urea ratio is an early marker of kidney function decline in the general adult population. Urea is easy to measure with well-standardized techniques and at low cost. Thus, the U/P urea ratio could become an easily available tubular marker for evaluating renal function decline.

Fluid homeostatic action of dapagliflozin in patients with chronic kidney disease: the DAPA-BODY Trial

Sodium glucose cotransporter 2 (SGLT2) inhibitors have both glucose-lowering and diuretic effects. We recently reported that the SGLT2 inhibitor dapagliflozin exerts short-term fluid homeostatic action in patients with chronic kidney disease (CKD). However, the long-term effects of SGLT2 inhibitors on body fluid status in patients with CKD remain unclear. This was a prospective, non-randomized, open-label study that included a dapagliflozin treatment group (n = 73) and a control group (n = 24) who were followed for 6 months. Body fluid volume was measured using a bioimpedance analysis device. The extracellular water-to-total body water ratio (ECW/TBW), a predictor of renal outcomes, was used as a parameter for body fluid status (fluid retention, 0.400 ≤ ECW/TBW). Six-month treatment with dapagliflozin significantly decreased ECW/TBW compared with the control group (-0.65% ± 2.03% vs. 0.97% ± 2.49%, p = 0.0018). Furthermore, dapagliflozin decreased the ECW/TBW in patients with baseline fluid retention, but not in patients without baseline fluid retention (-1.47% ± 1.93% vs. -0.01% ± 1.88%, p = 0.0017). Vasopressin surrogate marker copeptin levels were similar between the control and dapagliflozin groups at 6 months (32.3 ± 33.4 vs. 30.6 ± 30.1 pmol/L, p = 0.8227). However, dapagliflozin significantly increased the change in copeptin levels at 1 week (39.0% ± 41.6%, p = 0.0010), suggesting a compensatory increase in vasopressin secretion to prevent hypovolemia. Renin and aldosterone levels were similar between the control and dapagliflozin groups at 6 months, while epinephrine and norepinephrine (markers of sympathetic nervous system activity) were significantly lower in the dapagliflozin group than in the control group. In conclusion, the SGLT2 inhibitor dapagliflozin ameliorated fluid retention and maintained euvolemic fluid status in patients with CKD, suggesting that SGLT2 inhibitors exert sustained fluid homeostatic actions in patients with various fluid backgrounds. Clinical trial registration: https://www.umin.ac.jp/ctr/, identifier [UMIN000048568].

SGLT2 Inhibitors' Cardiovascular Benefits in Individuals Without Diabetes, Heart Failure, and/or Chronic Kidney Disease: A Systematic Review

Despite the growing body of evidence regarding the beneficial cardiovascular effects of sodium-glucose cotransporter-2 (SGLT2) inhibitors, clinical data in individuals without diabetes, heart failure (HF), and/or chronic kidney disease (CKD) is limited. A systematic review of the literature was conducted in PubMed, Scopus, Web of Science, Cochrane Library, and Google Scholar, from database inception until May 4, 2023, to explore new evidence of SGLT2 inhibitors' cardiovascular benefits in individuals without diabetes, HF, and/or CKD. A total of 1156 individuals from 14 studies (13 randomized controlled trials and 1 nonrandomized study) were included. The results showed the benefits of SGLT2 inhibitors on blood pressure, weight, and body mass index in this population with an acceptable safety profile. The current evidence supports the potential role of SGLT2 inhibitors as primary prevention in individuals without diabetes, HF, and/or CKD. This review may shed light on the use of SGLT2 inhibitors in conditions such as stage A HF and metabolic syndrome. The literature trend is going toward uncovering SGLT2 inhibitors' role in stage B HF, different types of myocardial infarction, and cardiac arrhythmias.

Blood pressure and vascular determinants of glomerular filtration rate decline in diabetic kidney disease

Objective

In patients with type 2 diabetes and diabetic kidney disease (DKD), explore the relationship between estimated glomerular filtration rate decline (eGFR-d) and simultaneously assessed vascular risk markers including office, ambulatory or central blood pressure, pulse pressure, carotid-femoral pulse wave velocity (PWV), carotid intima-media thickness (IMT) and renal resistive indexes (RRI).

Research design and methods

At baseline, vascular risk markers were measured in addition to the routine clinical workup. The eGFR-d was based on 2000-2019 creatinine values. Parameters were compared by eGFR-d quartiles. Regression models of eGFR-d and vascular markers were assessed.

Results

In total, 135 patients were included. Mean age was 63.8 ± 10.8y, baseline eGFR 60.2 ± 26.4 ml/min/1.73 m2 and urine albumin-creatinine ratio (ACR) 49 ± 108 mg/mmol. Mean eGFR-d was based on 43 ± 39 creatinine values within a time span of 7.0 ± 1.9y. The average yearly eGFR decline was -1.8 ± 3.0 ml/min/1.73 m2 ranging from -5.8 ± 2.3 in the first quartile to +1.4 ± 1.7 in the fourth quartile. Mean 24 h systolic (SBP) and diastolic (DBP) blood pressure were 126 ± 17 and 74 ± 9 mmHg. Mean PWV was 11.8 ± 2.8 m/s, RRI 0.76 ± 0.07 and IMT 0.77 ± 0.21 mm. SBP and pulse pressure correlated with eGFR-d but not DBP. 24 h SBP stood out as a stronger predictor of eGFR-d than office or central SBP. PWV and RRI correlated with eGFR decline in univariate, but not multivariate regression models including 24 SBP and ACR.

Conclusions

In this study, eGFR decline was highly variable in patients with type 2 diabetes and DKD. Twenty-four hour SBP provided an added value to the routine measurement of ACR in predicting eGFR decline, whereas PWV and RRI did not.

Canagliflozin ameliorates epithelial-mesenchymal transition in high-salt diet-induced hypertensive renal injury through restoration of sirtuin 3 expression and the reduction of oxidative stress

Hypertensive nephropathy is characterized by long-term damage to renal tissues by chronic uncontrolled hypertension, and ultimately leads to the development of renal fibrosis. The epithelial-mesenchymal transition (EMT) potentially contributes to the promotion of renal fibrosis in chronic kidney disease (CKD). In this study, we investigated the potential roles of canagliflozin (Cana) on renal EMT and oxidative stress through its effects on sirtuin 3 (SIRT3) expression. High-salt diet (HSD)-induced Dahl salt-sensitive rats hypertensive renal injury led to decreased SIRT3 expression and an increase in EMT and oxidative stress. In contrast, Cana administration rescued SIRT3 expression, decreased both EMT and levels of oxidative stress, and ameliorated renal injury. Furthermore, we compared the antihypertensive and renoprotective properties of Cana when combined with irbesartan (Irb), a renin-angiotensin system (RAS) blocker. We concluded that administration of Cana in combination with Irb had a significantly greater effect in lowering systolic blood pressure when compared to Cana monotherapy. However, no statistical differences were observed between combined therapy and monotherapy groups with regards to the lowering of diastolic blood pressure and renoprotection. Utilizing the human renal proximal tubular epithelial cell line (HK-2), Angiotensin II (AngⅡ) induced HK-2 negatively regulated the expression of SIRT3, FOXO3a, catalase, and promoted EMT, all of which were reversed by Cana. Furthermore, SIRT3 silencing abolished Cana-mediated rescue of forkhead box O3a (FOXO3a) and catalase expression and Cana-mediated suppression of EMT in AngⅡ induced HK-2. Taken together, Cana acts as a renoprotective agent by suppressing EMT in the pathology of renal fibrosis via interaction with the SIRT3-FOXO3a pathway.

Effects of a New Group of Antidiabetic Drugs in Metabolic Diseases

The prevalence of type 2 diabetes mellitus (T2DM) is rising in the general population. This increase leads to higher cardiovascular risk, with cardiovascular diseases being the main cause of death in diabetic patients. New therapeutic weapons for diabetes mellitus are now available. Sodium-glucose cotransporter type 2 (SGLT2) inhibitors are novel drugs that are widely used due to their strong benefit in preventing hospitalization for decompensated heart failure and renal protection, limiting the deterioration of the glomerular filtration rate, independently of the presence of diabetes mellitus. These drugs have also shown benefit in the prevention of atherosclerotic cardiovascular events and cardiovascular mortality in diabetic patients with established cardiovascular disease. On the other hand, patients with T2DM usually present a high burden of associated comorbidities. Some of these entities are arterial hypertension, dyslipidemia, hyperuricemia, obesity, non-alcoholic fatty liver disease (NAFLD), polycystic ovary syndrome (PCOS), vascular aging, respiratory diseases, or osteoporosis and fractures. Healthcare professionals should treat these patients from an integral point of view, and not manage each pathology separately. Therefore, as potential mechanisms of SGLT2 inhibitors in metabolic diseases have not been fully reviewed, we conducted this review to know the current evidence of the use and effect of SGLT2 inhibitors on these metabolic diseases.

Update on Hypertension Research in 2021

In 2021, 217 excellent manuscripts were published in Hypertension Research. Editorial teams greatly appreciate the authors' contribution to hypertension research progress. Here, our editorial members have summarized twelve topics from published work and discussed current topics in depth. We hope you enjoy our special feature, "Update on Hypertension Research in 2021".