ObjectiveIn our study, we evaluated the relation between calcium-phosphorus (Ca-P) product and various measurements of pre and post-dialysis blood pressure (BP) in hemodialysis (HD) patients.MethodsThis is a prospective, observational, cross-sectional study in which patients undergoing maintenance HD for > six months were enrolled through non-probability consecutive sampling during a six-month period from October 2020 to March 2021. Linear regression analysis was done to study the effect of the Ca-P product for each parameter of BP and regression coefficients were acquired.ResultsThere was a total of 111 patients in our study, of which 59 (53.2%) were male. The mean age was 50.1± 14.4. The most common comorbid was hypertension (98.2%). The mean HD vintage of patients was 5.7 ± 5.8 years. On linear regression analysis, the Ca-P product was strongly correlated with pre-HD diastolic BP (DBP) (0.7) and post-HD mean arterial pressure (MAP) (0.7) while a moderate correlation was present with pre (0.59) and post (0.64) HD systolic BP (SBP), post-HD diastolic BP (0.68), and pre-HD MAP (0.68). On the other hand, the Ca-P product was not correlated with pre and post-HD pulse pressure . When the independent effect of serum calcium (Ca), phosphorus (P), and parathyroid hormone on BP was studied, P had a significant correlation with pre and post-HD SBP, DBP, and MAP.ConclusionOur study demonstrates a significant association of the Ca-P product and an independent high P level with pre and post-dialysis SBP, DBP, and MAP while no association was found with pulse pressure. Hypertension (HTN) is a major risk factor for cardiovascular  and renaThe etiology of HTN in HD is multifactorial. Sodium and volume excess are considered the major reason for HTN in HD patients; however, other mechanisms, such as arterial stiffness, activation of the renin-angiotensin-aldosterone, sympathetic nervous systems, endothelial dysfunction, sleep apnea, and the use of erythropoietin-stimulating agents, may also be involved.Studies have also shown the association between parathyroid hormone (PTH) , plasma Arterial stiffness secondary to arterial calcification is associated with raised systolic blood pressure (SBP)  and meanAlthough P and Ca homeostasis is tightly regulated in the HD population as the management of bone mineral disorders, less attention has been paid to their potential involvement in the pathogenesis of atherosclerosis or as predictors of HTN and eventually cardiovascular disease -16. The The significance of HTN and its association with morbidity in HD patients demands the identification of non-traditional correctable factors to improve clinical outcomes in patients on hemodialysis. The sparsity of data on the correlation between the calcium-phosphorus (Ca-P) product and hypertension in ESRD patients particularly from our region, developed our interest in this subject. In the current study, we evaluated the relationship between different elements associated with a bone mineral disorder with various measurements of pre and post-dialysis BP in HD patients.This is a prospective, observational, cross-sectional study conducted in the Department of Nephrology, the Kidney Centre Postgraduate Training Institute (TKC-PGTI) after approval by the institutional ethical review committee. TKC-PGTI is a tertiary level renal care facility with a dialysis unit that accommodates 66 dialysis standards defined by European Best Practice Guidelines . Nearly A total of 111 patients of both gender, aged >18 years, undergoing maintenance hemodialysis for > six months, were enrolled after taking a written informed consent in the study through non-probability consecutive sampling during a six-month period from October 2020 to March 2021. Patients with malignancy, tuberculosis, liver cirrhosis, alcohol consumption, and gastrointestinal diseases that may have a misleading influence on calcium and phosphorus metabolism were excluded. Exclusion criteria also included patients who were non-compliant to dialysis therapy or not receiving the prescribed dialysis dose.Serum calcium, phosphorus, albumin, and hemoglobin were routinely measured once a month while serum intact parathyroid hormone (iPTH) levels were usually measured once in three months as per our dialysis unit’s protocol. Six-month averages of serum Ca, phosphate (PO4), the Ca-P product, parathyroid hormone (PTH), albumin, and hemoglobin were calculated. Data were collected from the patient's charts, maintaining confidentiality. Pre-dialysis and post-dialysis BPs were available in patient records for each dialysis treatment. One month’s BP measurements  were averaged in each of these patients. Measurements included pre and post-dialysis systolic blood pressure (SBP), diastolic blood pressure (DBP), MAP, and PP. Age, gender, primary diagnosis, comorbids, duration of hemodialysis, average ultrafiltration during dialysis, and the number of antihypertensive medications were included in the analysis.Statistical analysisData were entered and analyzed on IBM SPSS version 21, cleaning and coding of data were done before analysis. Mean ± Std and median with interquartile range (IQR) were calculated for continuous variables while frequencies with percentages were observed for categorical variables. The normality of data was checked by observing histogram, Q Q plot, box plot, and Shapiro Wilk's test. In the case of normally distributed data, Pearson correlation was computed to find any association between the calcium-phosphorus product, and different blood pressure parameters and correlation coefficient (R) were obtained. While for skewed variables, the Spearman correlation was applied. Linear regression was run to see the amount of effect of the Ca-P product on each parameter of BP and regression coefficients (R2) were acquired. A multiple linear regression analysis was performed to find adjusted regression coefficient (adjusted R2) of variables like age, gender, diabetes mellitus (DM), hemoglobin (Hb), number of antihypertensive medications, average ultrafiltration, and the Ca-P product with blood pressure. A P-value of ≤ 0.05 was considered significant.There were 111 patients in our study, of which 59 (53.2%) were male while 52 (46.8%) were female. The mean age was 50.1 ± 14.4. The most common comorbid was hypertension, which was present in 109 (98.2%) patients, followed by diabetes mellitus 39 (35.1%) while unknown kidney disease  was the most prevalent primary cause of chronic kidney disease ). The mean HD vintage of patients was 5.7 ± 5.8 years. Baseline characteristics of study patients are presented in Table We found that the Ca-P product strongly correlated with pre-HD diastolic BP (0.7) and post-HD mean arterial pressure (0.7) while a moderate correlation was present with pre (0.59) and post (0.64) HD systolic BP, post-HD diastolic BP (0.68), and pre-HD mean arterial pressure (0.68). On the other hand, the Ca-P product showed no correlation with pre (0.06) and post (0.1) HD pulse pressure Table .The Ca-P product had a profound impact on all parameters of BP except pulse pressure. In regression analysis, we found that patient’s blood pressure HD can be significantly predicted by the Ca-P product at a p-value of <0.001. The R2 value for pre-HD DBP depicts a 51% of variability, which can be accounted for by the Ca-P product. Similarly, 43% variance in the pre-HD SBP can be explained by the product of calcium and phosphorus and 46% variation in MAP. A similar impact of the Ca-P product can be seen in the post-HD parameters of BP  <0.001 for pre and post-systolic, diastolic BP, and MAP while p=0.027 for pre-HD pulse pressure and p=0.040 for post-HD pulse pressure). In multiple linear regression analysis, we found that the Ca-P product had a significant effect on pre and post-HD SBP, DBP, and MAP, when adjusted for age, gender, DM, Hb, the number of antihypertensive medications, and average ultrafiltration rate (p<0.001). Age was found to have a significant effect on pre-HD SBP (p=0.038) and PP (p=0.013) while gender had a significant effect on pre-HD DBP (p=0.012) and pre-HD MAP (p=0.017) when adjusted for the above-mentioned variables, including the Ca-P product. DM, Hb, the number of antihypertensive medications, and the average ultrafiltration rate had no significant effect on pre and post-BP parameters. We observed that variation in blood pressure could be better explained when we adjusted the Ca-P product with other regressors as compared to the individual effect on BP. The adjusted regression coefficients of pre and post-HD SBP, DBP, and MAP were increased in multiple linear analyses (Table We observed a significant association between the Ca-P product and BP in HD patients in our study. In a regression study, the Ca-P product was positively associated with pre and post-dialysis SBP, DBP, and MAP while no association was found between the Ca-P product and pulse pressure. While in a multiple linear regression analysis, we found that the Ca-P product was the only modifiable factor among DM, Hb, the number of antihypertensive medications, and the average ultrafiltration rate that had a significant effect on pre and post-HD SBP, DBP, and MAP. When we observed the independent effect of serum Ca, PO4, and iPTH on different readings of BP, serum PO4 was found to have a positive association with pre and post-SBP, DBP, and MAP, indicating the independent effect of PO4 in the physiologic mechanism of hypertension.Studies have shown the association between plasma calcium  and phosStudies that have evaluated the correlation between the Ca-P product and BP in HD found different results in the past. A study from China found no correlation between pulse pressure and plasma PTH levels or calcium-phosphorus products . A crossStudies that found an association of pulse pressure with the Ca-P product propose that PP is directed by the association between ventricular ejection and arterial stiffness. Arterial calcifications associated with elevated Ca-P product contribute to arterial stiffness, causing an increase in PP ,16. OtheOur study showed a positive association of the Ca-P product and independent PO4 with MAP but no association with PP. Similar findings were found in studies from China  and the Although our study is a single-center, observational, cross-sectional study, no direct causality could be established between the Ca-P product and BP measurements; however, a significant association can easily be ascertained from our study, which suggests the Ca-P product and P as important, non-traditional correctable factors and predictors of hypertension in HD patients. Extricating the complex regulatory pathways that mediate Ca and P’s effect on VSMCs will ultimately provide novel targets and therapies to limit the destructive effects of vascular calcification in CKD patients.Our study demonstrates the significant association of the Ca-P product and independent P levels with pre and post-dialysis SBP, DBP, and MAP while no association was found with pulse pressure. The Ca-P product and P are significant, non-traditional, correctable factors and predictors of hypertension in HD and need to be tightly regulated to improve clinical outcomes in patients on HD.


We included 40 patients from the medical intensive care unit at the Charité – Universitätsmedizin Berlin, Campus Benjamin Franklin between November 2019 and June 2020. The median age was 73 years. Forty percent of the study population was male; 98% was ventilator-dependent and 75% vasopressor-dependent at study entry. The mean of the observed differences for the cardiac output index (COI) was 0.7 l∗min–1*m–2 and the lower, and upper 95% limits of agreement (LOA) were -1.9 and 3.3 l∗min–1*m–2, respectively. The 95% confidence interval for the LOA was ± 0.26 l∗min–1*m–2, the percentage error 83.6%. We observed concordant changes in CO with MG and PiCCO® in 50% of the measurements after a fluid challenge and over the course of 6 h. Cardiac output calculation with a novel oscillometry-based pulse wave analysis method is feasible and replicable in critically ill patients. However, we did not find clinically applicable agreement between MG and thermodilution or calibrated pulse wave analysis, respectively, assessed with established evaluation routine using the Bland–Altman approach and with trending analysis methods. In summary, we do not recommend the use of this method in critically ill patients at this time. As the basic approach is promising and the CO determination with MG very simple to perform, further studies should be undertaken both in hemodynamically stable patients, and in the critical care setting to allow additional adjustments of the underlying algorithm for CO estimation with MG.While invasive thermodilution techniques remain the reference methods for cardiac output (CO) measurement, there is a currently unmet need for non-invasive techniques to simplify CO determination, reduce complications related to invasive procedures required for indicator dilution CO measurement, and expand the application field toward emergency room, non-intensive care, or outpatient settings. We evaluated the performance of a non-invasive oscillometry-based CO estimation method compared to transpulmonary thermodilution. To assess agreement between the devices, we used Bland–Altman analysis. Four-quadrant plot analysis was used to visualize the ability of Mobil-O-Graph (MG) to track CO changes after a fluid challenge. Trending analysis of CO trajectories was used to compare MG and PiCCO Cardiac output (CO) is a key determinant of oxygen delivery and thus an important parameter to assess the hemodynamic situation of critically ill patients, guide perioperative goal-directed therapy, and monitor response to therapeutic interventions . CO can In this study, we evaluated a non-invasive oscillometry-based pulse wave analysis CO estimation technique for use in critically ill patients.Eligible patients treated in the medical ICU of the Charité – Universitätsmedizin Berlin, Campus Benjamin Franklin were enrolled between November 2019 and June 2020. The Charité – Universitätsmedizin Berlin regional research ethics committee approved the study (ref: EA1/184/15). All methods were performed following the relevant guidelines and regulations.® device  as part of their ICU treatment were included in the study. Exclusion criteria were age below 18 years, pregnancy, known severe aortic valve, aortic arch, axillary, or brachial artery stenosis, as well as cardiac arrhythmias precluding non-invasive calculation of haemodynamic parameters. Patients were considered haemodynamically unstable if mean arterial pressure (MAP) was <65 mmHg or vasopressor therapy was necessary to maintain MAP ≥ 65 mmHg.Only patients monitored hemodynamically with the invasive CO determination PiCCO®  blood pressure monitoring device equipped with an improved CO calculation algorithm . With MG, CO is estimated from the arterial pulse wave derived with a high fidelity pressure sensor integrated into the blood pressure cuff while being inflated at diastolic blood pressure level for 10 s. Cuff size was chosen according to manufacturer instructions: regular size for arm circumferences of 24–34 cm, large size for arm circumference 32–42 cm. The measurement site was left or right upper arm. The construction of the aortic pressure waveform was made using generalized transfer functions  and transformation from aortic pressure to aortic flow waveform was performed with an adopted, and multidimensional Windkessel model. Basic principle used is derivation of stroke volume (SV) from pulse contour analysis (PCA) determined with oscillometry. SV is proportional to the area of the flow curve during systole. The computation of the aortic flow from pressure was based on the 3-element windkessel model determined by aortic characteristic impedance, aortic compliance and peripheral resistance. These parameters were identified using Levenberg–Marquardt algorithm. SV was derived from the time lag between aortic pressure and flow curve . Finally, CO was calculated by multiplying SV with the heart rate. Detailed underlying mathematical principles related to CO estimation with MG are described elsewhere (The test device for non-invasive CO estimation was the Mobil-O-Graph (MG)lsewhere . For com® system: A bolus of 20 mL of cold (0–6°C) 5% glucose solution was manually injected (injection time ≤ 10 s) into the distal lumen of a central venous catheter while the patient was in a supine position and then detected in the systemic circulation by a thermistor-tipped femoral artery catheter . As with MG CO estimation, two consecutive CO measurements were performed, a mean was calculated for inclusion in the final analysis and COI calculated.Reference CO was measured using transpulmonary thermodilution with the PiCCO®) devices before, and after a fluid challenge with 150 mL of crystalloid solution. In addition, we performed trend analyses with MG and PiCCO® -calibrated pulse wave analysis over a maximum of 6 h (We performed CO measurements with the test (MG) and reference  and SPSS Statistics 25.0 . Continuous variables are presented as median with quartiles. Categorical variables are presented as absolute numbers with percentages. Statistical differences between paired measurements were assessed using a nonparametric Wilcoxon test, and a two-sided ntervals . FurtherFor the purpose of the study, we defined an exclusion zone of 15% . To comp®, respectively, but also between non-invasive and invasive blood pressure measurements: Both diastolic and MAPs were significantly higher with MG than measured invasively in the femoral artery . Conversely, systolic blood pressure was lower with MG than with invasive measurement (118 vs. 123 mmHg), even though this difference was not statistically significant. Both CO and COI were significantly lower with MG as compared with PiCCO® . Obtained CO values ranged from 3.2 to 10.7 l∗min–1 for MG and from 2.9 to 17.8 l∗min–1 for PiCCO®. Further details concerning hemodynamic parameters are depicted in We included 45 participants in the study. Five patients had incomplete measurement data sets due to technical problems so that 40 patients were included in the final analysis. The median age was 73 years, 40% of the study population was male, 98% was ventilator-dependent, and 75% vasopressor-dependent at study entry. Clinical and demographic parameters are presented in r = 0.40; p < 0.0001). Findings for COI are presented in r = 0.28 (p = 0.02), which is shown in Cardiac output and COI obtained with MG significantly correlated with CO and COI obtained with reference device , and central (invasive) measurements have been compared in critically ill patients. Imprecise estimation of central arterial pressure during hemodynamic instability can influence the accuracy of derived CO  under static conditions and its ability to trend the changes in CO after fluid challenge and over a course of several hours in critically ill patients. We found a moderate correlation between CO estimation with MG and reference PiCCOr method . We, thur method . In our r method . Usuallyr method . Howeverrived CO .Plenty of non-invasive CO monitoring devices, which rely on non-invasive pulse wave analysis, pulse wave transit time, or thoracic bioimpedance as a basic principle for CO calculation, have been described in the literature . AcknowlAlgorithmic refinements had been made by the manufacturer in 2018. Compared to a previous study with the older software we observed a lower mean bias with comparable LOA and higher percentage error in this study . A recen® in 50 percent of the measurements after volume change and over several hours, which points to a weak concordance. Of note, in 67% of cases with non-concordant CO changes recordings were performed while the patients received high-dose vasopressor therapy. Similar findings were reported for other CO calculation methods (In the clinical setting tracking CO changes with therapy or overtime is usually more important than the determination of single absolute CO values. Our study is one of the few, in which not only CO response to a singular fluid challenge was considered, but also the ability to track CO changes over a longer period. We observed concordant changes in CO with MG and PiCCO methods . Indeed, methods .We acknowledge several limitations of the study. The number of enrolled subjects was relatively small. We did not use pulmonary artery catheter as the reference method. The vasopressor doses possibly contributing to significant variation in calculated CO varied between the subjects. Arterial compliance has a major influence on CO estimation derived from pulse wave analysis. Rapid changes in vasomotor tone, in particular with higher vasopressor dose, can have an impact on arterial compliance and consequently impair the CO estimation. Due to the non-randomized study design, we cannot account for all possible confounding factors, which may influence the CO. We did not compare BP values between both arms prior to the validation.To conclude that CO calculation with a novel oscillometry-based pulse wave analysis method is feasible and replicable in critically ill patients. However, a clinically applicable agreement between MG and thermodilution used as a reference method in critically ill patients was not observed using the Bland–Altman approach and with trending analysis methods. In summary, we do not recommend using this method in critically ill patients at this time. As the basic approach is promising and the CO calculation with MG very simple, further studies should be performed in hemodynamic stable patients and critical care setting to gain additional data to be able to further adjust the underlying algorithm for CO determination in this device.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.The studies involving human participants were reviewed and approved by Charité Ethics Committee. The patients/participants provided their written informed consent to participate in this study.AR: conception of design, analysis and interpretation of the data, drafting the article, and final approval of the version to be published. JG: conception of design, analysis and interpretation of the data, and drafting the article. MG: conception of design and providing intellectual content of critical importance. FC: interpretation of the data, revising the article, and final approval of the version to be published. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Incretin therapies appear to provide cardioprotection and improve cardiovascular outcomes in patients with diabetes, but the mechanism of this effect remains elusive. We have previously shown that glucagon-like peptide (GLP)-1 is a coronary vasodilator and we sought to investigate if this is an adenosine-mediated effect.We recruited 41 patients having percutaneous coronary intervention (PCI) for stable angina and allocated them into four groups administering a specific study-related infusion following successful PCI: GLP-1 infusion (Group G) (n = 10); Placebo, normal saline infusion (Group P) (n = 11); GLP-1 + Theophylline infusion (Group GT) (n = 10); and Theophylline infusion (Group T) (n = 10). A pressure wire assessment of coronary distal pressure and flow velocity (thermodilution transit time—Tmn) at rest and hyperaemia was performed after PCI and repeated following the study infusion to derive basal and index of microvascular resistance (BMR and IMR).p = 0.65. Theophylline alone (group T) did not significantly alter resting flow velocity compared to group GT: delta Tmn in group T 0.04 s (0.15), p = 0.30. The resulting decrease in BMR observed in group G persisted in group GT: − 20.83 mmHg s (24.54 vs. − 21.20 mmHg s (30.41), p = 0.97. GLP-1 did not increase circulating adenosine levels in group GT more than group T: delta median adenosine − 2.0 ng/ml  versus − 0.5 ng/ml ; p = 0.60.There were no significant differences in the demographics of patients recruited to our study. Most of the patients were not diabetic. GLP-1 caused significant reduction of resting Tmn that was not attenuated by theophylline: mean delta Tmn (SD) group G − 0.23 s (0.27) versus group GT − 0.18 s (0.37), The vasodilatory effect of GLP-1 is not abolished by theophylline and GLP-1 does not increase adenosine levels, indicating an adenosine-independent mechanism of GLP-1 coronary vasodilatation.Trial registration: The local research ethics committee approved the study : REC reference 14/EE/0018. The study was performed according to institutional guidelines, was registered on http://www.clinicaltrials.gov (unique identifier: NCT03502083) and the study conformed to the principles outlined in the Declaration of Helsinki.The online version contains supplementary material available at 10.1186/s12872-021-02030-5. Cardiovascular disease is the leading cause of death across the world, predominantly related to atherosclerosis . DiabeteSafety trials of contemporary hypoglycaemic treatments for type-2 diabetes mellitus have demonstrated beneficial reductions in cardiovascular outcomes –6. One cAdenosine is a naturally occurring compound that binds to A2A and A2B receptors in the microcirculation , exertinWe have undertaken a mechanistic study to explore whether GLP-1 causes coronary microvascular vasodilatation via an adenosine-mediated pathway in humans.One hundred and one patients with stable angina awaiting elective angiography were screened and thirty-one patients were found to be eligible and gave informed written consent. Out of these, nine patients had non-obstructive coronary arteries and therefore, did not require stenting. Two further patients had complex coronary anatomy: one requiring left main bifurcation stenting and the other had surgical revascularization, and therefore were excluded from our study.2 by Modification of Diet in Renal Disease (MDRD); deranged liver function with alanine transaminase (ALT) > 3 times upper limit of normal; active peptic ulcer disease confirmed on endoscopy; history of seizures; history of tachyarrhythmias; patients already taking oral theophylline; allergy to theophylline or caffeine.Inclusion criteria included patients undergoing elective PCI for stable angina; age above 18 years; and able to give informed consent for the study. Exclusion criteria included any severe co-morbidity with expected life expectancy < 6 months; use of warfarin, nicorandil, glibenclamide, sitagliptin, vildagliptin, saxagliptin, linagliptin, alogliptin, exenatide, liraglutide, lixisenatide and insulin use; women of child-bearing age; breast-feeding women; myocardial infarction within the previous 3 months in a remote territory; heart failure with ejection fraction < 50%; deranged renal function with eGFR < 60 ml/min/1.73 mTwenty patients having percutaneous coronary intervention (PCI) were studied in two groups: those receiving post-PCI infusions of GLP-1 + Theophyline (Group GT) and Theophylline (Group T) respectively. Data from these two groups were compared with historically-recruited patients who received GLP-1 infusion (Group G) and placebo  (Group P) . TheophyAll patients received aspirin, 300 mg and clopidogrel, 300 mg preloading, unless they were already established on these antiplatelets. Patients were anticoagulated with a heparin bolus (70–100 U/kg) after arterial sheath insertion  to achieve an activated clotting time > 250 s. Iopromide  was used as the contrast agent for all cases. The choice of stent and implantation technique was left to operator discretion. Following successful stent implantation baseline bloods were taken to measure serum adenosine levels using a Stop solution.A Pressure wire X , connected wirelessly to Coroflow , was positioned and maintained in the distal third of the stented coronary artery. A 0.2 mg bolus of intracoronary glyceryl trinitrate (GTN) was administered, and once steady state coronary haemodynamics were achieved, the baseline coronary pressures [aortic pressure (Pa) and distal wire pressures (Pd)] and flow velocity measurements were measured. The latter was derived from the reciprocal of mean transit time (Tmn) of an intracoronary injectate of room temperature saline (thermodilution technique) measured in triplicate , 18. TheAn intravenous infusion of GLP-1 (1.2 pmol/kg/min)(7–36) amide  and an adenosine receptor inhibitor, theophylline (5 mg/kg in 100 ml 0.9% NaCl over 20 min) or GLP-1 or Theophylline (5 mg/kg in 100 ml 0.9% NaCl over 20 min)  or Placebo (100 ml 0.9% NaCl over 20 min) was infused depending upon patient’s group. At the end of infusion, a repeat blood sample was taken from the coronary catheter to measure theophylline and adenosine levels. All the haemodynamic measurements were repeated at rest and hyperaemia after completion of the infusion, usually within 30-min of baseline. At the end of the procedure, the pressure wire was withdrawn to the coronary ostium to enable pressure-drift correction of Pd, if necessary. Pv was assumed to be 5 mmHg in all the patients in this study.baseline) and index of microvascular resistance (IMR = Pa × Tmn × ((Pd − Pw)/(Pa − Pw)) hyperaemia), both corrected for collaterals, fractional flow reserve, (FFR = (Pd)/(Pa)hyperaemia), coronary flow reserve (CFR = (Tmn) baseline/(Tmn)hyperaemia) and collateral flow index by pressure (CFIP = (Pw − Pv)/(Pa − Pv)baseline) and coronary resistive reserve ratio (RRR = BMR/IMR), as previously described and validated [These measurements enabled offline calculation of, basal microvascular resistance (BMR = Pa × Tmn × ((Pd − Pw)/(Pa − Pw))alidated , 20  after administration of GLP‐1.p < 0.05 was deemed significant. Authors had full access to the data and take full responsibility its integrity.Data are given as mean (SD) or median  as appropriate unless otherwise stated. Comparisons were made for any significant differences by unpaired T test, one-way ANOVA or Kruskal–Wallis test, where appropriate using GraphPad Prism version 8.1.2 (227) . Similarly, a simple linear regression was performed between resting adenosine levels and basal coronary flow velocity before and after the study infusion to explore any correlation. A two-sided value of Baseline characteristics are summarized in Table p = 0.97 respectively, confirming that theophylline did not attenuate the GLP-1 vasodilatory effect in group GT  in group G: − 1.00  and in group GT: − 0.88  compared to 2.01  in group S and − 0.16  in group T, p = 0.03,  versus T, − 0.50 ng/ml , p = 0.60.The mean theophylline levels measured at the end of infusion were in the therapeutic range (10–20 mcg/ml) and similar between GT and T groups: 13.58 mcg/ml (4.48) versus 15.05 mcg/ml (2.15), There was no correlation found in the measured adenosine levels and basal coronary flow velocity, before or after the study infusion  channel-dependent pathway  and is aWe clearly demonstrate in this study that GLP-1 vasodilatation is unlikely to be the mediated by adenosine. GLP-1 increases basal coronary flow velocity and reduces BMR irrespective of theophylline. GLP-1 exhausts vasodilatory capacity, such that response to exogenous adenosine is blunted as measured by a reduction in CFR and RRR. Theophylline has been used to investigate adenosine-mediated effect of other therapies; it is a potent adenosine receptor inhibitor at levels achieved in our study . In addiCoronary microvascular dysfunction (CMD) is associated with worse clinical outcomes  and micrThere are several limitations in our study. Firstly, this was not a randomized controlled trial but was performed in two phases by block allocation to understand the mechanistic effects of GLP-1 on coronary physiology. However, the patients were unselected and sequentially recruited if eligible, and we believe this prevented significant bias. Second, we studied the coronary vasodilatory effects of GLP-1 following PCI. Coronary physiology may not be stable at this time due to reactive hyperaemia and microvascular stunning , 40; howThe coronary vasodilatory effect of GLP-1 appears to be independent of adenosine. Further studies are required to understand the mechanism of the cardioprotective effects of GLP-1.Additional file 1: Supplemetary Figure. Sactterplot of the relationship between A) pre and B) post infusion adenosine concentration and Tmnrest.


The systolic and diastolic blood pressure of the subjects was significantly reduced from 137.9 ± 15.7mmHg to 123.0 ± 16.0 and 83.4 ± 10.8 to 71.3 ± 11.7mmHg (P<0.001), respectively. The levels of fasting insulin and fasting blood glucose were significantly decreased . Total cholesterol  and triglyceride  decreased significantly. Cardiovascular geometric parameters including aortic sinus diameter , left atrial diameter , and interventricular septum thickness were significantly reduced. The ratio of weight loss (RWL) was positively correlated with the changes of LAD. The change of IVS was negatively correlated with the change of fasting blood glucose (GLU). Weight loss after LSG could effectively improve cardiac structural, but not functional, abnormality in obese Chinese.This study aimed to investigate the impact of weight loss after laparoscopic sleeve gastrectomy (LSG) on cardiac structural and functional remodeling in obese Chinese. A total of 44 obese participants were enrolled consecutively. The physical, laboratory, electrocardiographic, and echocardiographic parameters of pre-and postoperative were recorded. The average follow-up time was 12.28 ± 5.80 months. The body mass index (BMI) of the patients with obesity was decreased from 41.6 ± 7.44 to 30.3 ± 5.73kg/m According to statistics, the number of obese people in the world exceeded 650 million in 2016, and the prevalence is on the rise  is more than 30kg/mthe rise . The trathe rise . However2 or BMI≥ 27.5kg/m2 with other comorbidities (The flowchart of the study was shown in bidities . The exc2. The ratio of weight loss (RWL) was defined as the change of body weight dividing the preoperative weight. The systolic blood pressure (SBP) and diastolic blood pressure (DBP) of the patients with obesity was measured according to the guideline , and the use of antihypertensive drugs. The operation time and follow-up time were recorded. The BMI was calculated by the formula: weight/heightuideline .The subjects’ fasting venous blood serum samples were taken before operation and at the follow-up to test related parameters, including low density lipoprotein (LDL), total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL), free fatty acid (FA), fasting blood glucose (GLU), fasting insulin (Ins) and glycosylated hemoglobin A1c (HbA1c).1/2.The subjects were required to take a standard resting electrocardiogram examination by a trained physician using the Cardiofax S ECG machine . A 10s 12-leads synchronous electrocardiogram was recorded, with a paper speed of 25 mm/s and an amplitude of 10 mm/mV. HR was measured according to the RR interval on ECG. PR referred to the interval from the start of the P wave to the start of QRS complexes. The corrected QT interval (QTc) was calculated using Bazett’s formula: QT/RR3)+0.6 (Echocardiography was blindly performed by an experienced echocardiographer using a MyLab 30 cardiovascular machine (ESAOTE SPA) with a 3.5MHz probe, according to the American Society of Echocardiography recommendations . The aor3)+0.6 . The peaP <0.05.All statistical analyses were performed using the SPSS20.0 software . All continuous variables were presented as mean ± SD and categorical variables were presented as percentages. The changes of parameters before and after LSG were represented by Δ. The continuous indexes of preoperative and postoperative were compared by paired sample t-test and the percentages by the chi-square test. The bivariate relationship between the cardiac parameters and cardiovascular risk factors was studied by Pearson correlation analysis. Multiple linear regression analysis was used to assess the correlation between cardiac parameters and cardiovascular risk factors. The hypothesis testing can be considered to be of statistical significance when 2 (P<0.001). 11 patients had hypertension (HTN) diagnoses 3 [1-20] years before the LSG, 8 of which have taken the antihypertensive drugs. The proportion of subjects who had taken the antihypertensive drugs would be reduced  and the types of antihypertensive drugs also reduced  after LSG. Meanwhile, the systolic and diastolic blood pressure of the subjects who had not taken the antihypertensive drug was reduced . The levels of fasting insulin and fasting blood glucose were significantly decreased , and HbA1c decreased from 7.10 ± 2.39 to 5.50 ± 0.37% (P<0.001). LDL , TC , TG  and HDL  have been improved to a certain extent, relatively. However, FA failed to reach a statistically significant decrease. The basic characteristics and the changes of conventional cardiovascular risk factors and metabolism variables at baseline and follow-up were described in A total of 44 subjects participated in the study, including 18 men and 26 women. The mean age of the subjects was 32.4 ± 9.6 years old, and the average follow-up time was 12.28 ± 5.80 months. The proportion of subjects taking antihypertensive drugs was 18% and that of smokers was 9%. The BMI of the patients with obesity after LSG decreased significantly from 41.6 ± 7.44 to 30.3 ± 5.73kg/mP<0.001) after LSG. There was no significant change in PR interval. In one of the subjects, who was treated with a β-receptor blocker for a long time, the QTc significantly extended to 619 ms, which met the diagnostic criteria of long QT interval syndrome. Excluding this outlier value, QTc significantly shortened from 438.1 ± 22.3 to 421.0 ± 17.6ms (P<0.001). The subjects had a significant reduction in ASD and LAD after weight loss , while LVEDD and LVESD did not change significantly. The subject’s IVS and PWT were thinner than before surgery . The LVmass was reduced from 275.0 ± 64.2 to 249.7 ± 54.3g(P<0.05). However, the LVEF and Sa had no significant change. These changes in changes in BMI, cardiac electrophysiological, structural, and functional parameters were shown in The changes in electrocardiographic and echocardiographic parameters were summarized in P<0.01, P>0.05, The population was divided into low (L), middle (M), and high (H) subgroups according to the tri-sectional quantiles of RWL or the change of GLU. Among the subgroups, the change of LAD was different  for the publication of any potentially identifiable images or data included in this article.YX and YZha designed the article. WM and RP drafted and revised the manuscript under the supervision of YZha. LD collected basic information of participants. DL, YZhe, and SQ contributed to the manuscript editing. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Women not only have worse diabetes complications, but also have menstrual cycle, pregnancy, and menopause which can make managing diabetes more difficult. The aim of this study was to investigate if radial pressure wave analysis may non-invasively screen for women’s risk of type 2 diabetes.Spectrum analysis of the radial pressure wave was performed to evaluate the first five harmonic components, C1 to C5. The study consisted of a total of 808 non-pregnant female subjects aged 20–95 over the period of 4 years, and 404 of them were diagnosed with Type 2 diabetes as the case group.The first five harmonic components are significantly different in a comparison of the case group and the control group. In the logistic regression analysis, T2DM was found to be associated with C1 , C2 , and C3 . In the Receiver Operating Characteristic curve analysis, the Area Under Curve of using C3 only , weighted C1, C2 and C3, , and weighted C1, C2 and C3 and Body mass Index  were tested for the accuracy on how well these tests separate the women into the groups with and without the T2DM.We thus concluded that pulse spectrum was a non-invasive predictor for women’s risk of T2DM. Pregnancy and menopause have profound effects on the risks for diabetes and therefore warrant more aggressive diagnostic attention and monitoring . Women wRadial pressure wave describes the change of the arterial pressure over time and provides information of the condition of ventricular-arterial system . ChangesIn our previous study, the harmonic indexes of radial pulse could be risk factors for complications of diabetes especially for the cardiovascular complications . Beside,The subjects of this study were all Asians, aged 20–95 years, recruited by Taipei City Hospital between August 2016 and February 2020. Both oral and written information about the study was given to the patients. Informed consent was obtained from all patients after receiving approval from the Institutional Review Board of Taipei City Hospital (IRB number: ISRCTN20480882). The case group of women with type 2 diabetes were under the care of the Division of Endocrinology & Metabolism at Zhongxiao Branch and the control group were patients randomly selected from the Department of Gynecology and Obstetrics at the Renai Branch. Patients with diabetes, major cardiovascular disease, kidney disease, liver disease and cancer would seriously affect the circulatory system were excluded from the control group, and pregnant subjects were excluded from this case and control analysis.A non-invasive radial pulse measurement was employed to test whether there is a relationship between type 2 diabetes (T2DM) and the first five harmonics of the radial pulse. Each subject’s radial pressure wave data was continuously recorded for 12-seconds using a medical grade pulse measuring instrument . Briefly, a piezoresistive sensor is used to record pressure waveforms from the radial artery of the wrist. TD01C proved its intrinsic reliability using artificial pulse generator . The intAging is a known risk factor for T2DM and the risk increases by age . Age alsAll statistical analyses were performed using R version 3.0.2. A T-test was used to compare variables between case and control groups. The logistic regression analysis was used to determine the associations between T2DM and harmonics indexes and the odds ratios. Age, BMI, Systolic blood pressure (SBP) and Diastolic blood pressure (DBP) were controlled by acting as the covariates in the logistic regression model. The Area Under Curve (AUC) was tested for the accuracy on how well these tests separate the women into the groups with and without the T2DM. ROC analysis was used to calculate the sensitivity and specificity of the variables and the cut off points . Lastly,In To investigate the association between T2DM and the radial pressure wave harmonics, we apply the logistic regression of the generalized linear model. BMI was controlled by acting as the covariates in the logistic regression model.After controlling age, BMI, SBP and DBP, C1 and C2 were positively and C3 was negatively associated with T2DM. Odds ratios obtained from logistic regression describe associations of BMI, C1, C2 and C3 with T2DM In logistic regression analysis, T2DM was found to be positively associated with BMI , C1 , C2 , and negatively associated C3  values in The receiver operating characteristics (ROC) curve of each predictor was obtained, and the AUC was seen as the evaluation criteria of the performance of prediction.Besides the single BMI and C3 predictor, the combination of all the predictors were also tested, with the corresponding coefficients of variables in the logistic regression models were also used as the weighting parameter . Since aSince SBP, DBP, C4 and C5 were not significant in the logistic regression model, the cut points are weighted by coefficients of the logistic regression with BMI , C1 , C2  and C3  excluding C4 and C5. The cut point with the highest Youden Index is 0.330. At this cut point, the specificity was 0.861, the sensitivity was 0.686.We assumed the prevalence of T2DM in female Taiwanese as 10% based on the government study . Based oThere is a trade-off between sensitivity and specificity that is dependent on the cut-off level chosen for a positive diagnosis . If thosIn summary, the study confirmed that general and abdominal obesity are known significant risk factors for diabetes in the future. BMI was strongly associated with diabetes incidence in women . in addiIn a study of 84,000 female nurses for 16 years, it has found that being overweight or obese was the single most important predictor of T2DM . Our stuOut of 404 female patients with type 2 diabetes, 24.8% of them were coded with ICD 10 between I00 and I99, diseases of the circulatory system. The relationship between radial pulse waves and status of ventricular-arterial system was illustrated in the past studies . A 1.8 yC2 and C3 were also previously reported to be related to the blood circulation of the renal artery and superior mesenteric artery (SMA) respectively. Young et al. informed that 3 seconds ligating of the left renal artery caused changes to C2 and ligating the SMA caused changes to C3 . 42.9% oMany studies  have beeThe combination of BMI and arterial radial pressure wave is a very useful first-step screening test to identify women at risk for diabetes. Investigating if the male patients and other ethnic groups have the similar trend will be imperative in the future. In addition, due to insufficient clinical data, some risk factors associated with diabetes and blood pressure, such as Low-density lipoprotein, cholesterol, smoking, medication use, family history, and history of other cardiovascular or chronic diseases, were not considered in this study. Future research will consider these important factors at the same time to revise the predictive indicators and conduct longitudinal research. A longitudinal study of each patient may also provide additional insights into if radial pressure wave changes after diagnosis of T2DM. This may be especially beneficial in the age of telemedicine or screening in those regions with less access to medical resources .In conclusion, beyond the common risk scores for type 2 diabetes to identify women at high risk, non-invasive measurement of arterial radial pressure wave provides supplementary and independent predictive value.S1 Dataset(XLSX)Click here for additional data file.


There is limited knowledge of the effects of blood pressure (BP) lowering oncerebral haemodynamics after transient ischaemic attack (TIA) andnon-disabling stroke, particularly at older ages. We aimed to evaluatechanges in transcranial Doppler (TCD) haemodynamic indices in patientsundergoing early blood pressure lowering after TIA/non-disabling stroke,irrespective of age.2 and bilateral middle cerebral artery (MCA) velocityon TCD were compared in the acute setting versus one-month follow-up;changes were stratified by baseline hypertension (clinic-BP≥140/90) and byage .Among consecutive eligible patients attending a rapid-access clinic withsuspected TIA/non-disabling stroke and no evidence of extra/intracranialstenosis, hypertensive ones underwent intensive BP-lowering guided by dailyhome telemetric blood pressure monitoring (HBPM). Clinic-based BP, HBPM,End-tidal COp < 0.0001) at one-month (133.7/17.4 mmHg), drivenby patients hypertensive at baseline . Compared with baseline, a significant change was observedat one-month only in mean/SD MCA end diastolic velocity (EDV) and in resistance index (RI), driven by hypertensive patients. Findings were similar at all ages,including 117 patients aged ≥80. EDV and RI changes were largest in 100patients with clinic systolic-BP decrease ≥30 mmHg .In 697 patients with repeated TCD measures, mean/SD baseline systolic-BP(145.0/21.3 mmHg) was reduced by an average of 11.3/19.9 mmHg(There was no evidence of worsening of TCD haemodynamic indices associatedwith BP-lowering soon after TIA/non-disabling stroke, irrespective of ageand degree of BP reduction. In fact, EDV increase and RI decrease observedafter treatment of hypertensive patients suggest a decrease in distalvascular resistance. Blood pressure (BP) lowering after stroke or transient ischaemic attack (TIA)also reduces the risk of recurrent stroke,6 but some uncertainties remain.Firstly, there is limited evidence on the effectiveness of BP-lowering in randomisedtrials in older (>80 years) patients with TIA/stroke. In most trials on antihypertensive treatment for secondary stroke prevention,including the PROGRESS trial, older patients were underrepresented. Secondly, there is uncertainty abouthow early antihypertensive treatment should be initiated. There is no evidence ofbenefit, and even possible harm, from acute initiation of treatment in major acute stroke. Although patients with TIA/non-disabling stroke are also often started onantihypertensive treatment in the acute setting, the effects of intensive blood pressure lowering on cerebral perfusion inthese patients are uncertain, particularly at older ages. Small studies onTIA/stroke patients10 without carotid occlusive disease showed no evidence ofworsening cerebral perfusion, but observation was limited to 2 weeks afterinitiating BP-lowering, and few older patients were studied. Reduced cerebral bloodflow at older ages could place elderly patients at higher risk of cerebral hypoperfusion, particularly those with decreased diastolic flow and increasedcerebrovascular resistances, which is associated with cognitive decline.12Treatment of hypertension is safe and effective in elderly patients in primaryprevention, but guidelines for TIA/stroke make no comment on BP-lowering in olderpatients and do not address the timing of treatment.15 Uncertainty aboutage-specific thresholds and about timing might partly explain underprescription ofantihypertensive medications after TIA/stroke,18 particularly if decisions aredelayed, given that in-hospital prescription is known to be the strongest predictorof long-term adherence. High blood pressure in hypertensive subjects is associated with reducedcerebral blood flow,20 and with further decline with increasing age in longitudinalcohorts,22 but there is evidence of an increase in cerebral blood flowafter intensive blood pressure lowering in older hypertensive subjects withouthistory of stroke. In the absence of randomised trials comparing different BP-targets in elderlypatients with TIA/non-disabling stroke, or of immediate versus delayed initiation ofmedication, data on the physiological effects of early BP-reduction might providesome support for clinical decision making. We hypothesised that intensiveBP-lowering would not decrease transcranial Doppler (TCD) blood flow velocities, andin particular end-diastolic velocity, in older patients with recent TIA/stroke withno intra/extracranial carotid stenosis.Guidelines for management of hypertension in primary prevention set more cautiousBP-thresholds as treatment goals in older patients, (Supplementary Methods). From 1 November 2011, all eligible patientsattending the OxVasc rapid-access TIA/stroke clinic underwent additional phenotyping(OxVasc Phenotyped Cohort), including TCD ultrasound and telemetric home bloodpressure monitoring (HBPM); patients with presumed TIA or non-disabling stroke wereeligible for inclusion in this study if they had no evidence of significantextra/intracranial stenosis of the anterior circulation (no stenosis or up to<50%), were willing and able to come back to clinic for one-month follow-upassessment and had a temporal bone window suitable for insonation.We studied TCD parameters in a large population-based cohort attending a rapid-accessclinic, undergoing early blood pressure lowering soon after TIA/non-disablingstroke, irrespective of age. The study was nested in the Oxford Vascular (OxVasc) StudySupplementary Methods). Demographic data, atherosclerotic riskfactors including male sex, history of hypertension, diabetes mellitus,hypercholesterolemia, smoking habit (ex or current smoker), history of atrialfibrillation and ongoing medications were also recorded at initial face-to-faceinterview and cross-checked with primary care records.During acute clinical assessment, brain and vascular imaging were obtained  was performed by one of the three experiencedoperators , who were unaware of the patient’s clinical presentation,as detailed in the Supplementary Methods).Patients carried on HBPM with a Bluetooth-enabled telemetric blood pressure monitor(IEM Stabil-o-Graph or A&D UA-767 BT) until at least the 1 month follow-upappointment, if tolerated , plus clopidogrel (300 mg loading doseand then 75 mg for 30 days) for high risk patients; atorvastatin (40–80 mg daily);antihypertensive treatment (unless systolic blood pressure was below 130 mm Hg onrepeated measurement), according to a standardized protocol: a combination ofperindopril arginine 5 mg and indapamide 1.25 mg followed by addition of amlodipine5/10 mg, if necessary. internal carotid artery (ICA) or MCA stenosis on vascular imaging. Toreduce the risk of selection bias, the main analysis included patients recruitedwith what was considered initially to be a TIA, but in whom an alternativediagnosis was subsequently made on the basis of further investigation at follow-up, as well as patients with recurrent ischemic stroke between baseline andfollow-up assessment.Analysis included all eligible patients recruited between 1 November 2011 and 30November 2018 who underwent TCD ultrasound and had no evidence of ≥50% Measures of clinic systolic blood pressure (SBP) and diastolic bloodpressure (DBP) were given as the mean/SD of two measurements taken before andafter each TCD scan. Mean End-tidal CO2 (EtCo2) was givenas the average of the readings recorded throughout the procedure at eachtime-point.Haemodynamic TCD measures of peak systolic velocity (PSV), end diastolic velocity(EDV), mean flow velocity (MFV), pulsatility index (PI) and resistance index(RI) were given as a mean/SD of the average of two measurements on each side ateach time point.The difference between one-month follow-up and baseline measure for each variablewas expressed as mean (mean one-month – mean baseline)/SD, with negative valuesreflecting a decrease between the two time-points.Paired t test was used to compare blood pressure and haemodynamic parameters atbaseline, at one-month follow-up and changes between the two time points in theanalysis on the whole cohort, stratified by clinic and HBPM blood pressure andby age . as office-based blood pressure ≥140/90 mmHg and HBPM-based ≥135/85 mmHgduring the first 3 days of HBPM (Supplementary Methods).To maximise precision of measurement of blood pressure changes, we also ran theanalysis of hemodynamic changes in those patients in whom blood pressurereduction (with a target of <130/80) was guided by telemetric HBPM throughoutthe first month. ‘Hypertension’ at baseline was defined according to the ESC classificationChanges between baseline and follow-up of blood pressure and TCD parameters wereanalysed in the group of patients without antihypertensive treatment at baselineand follow-up, to explore the range of spontaneous variations of physiologicalparameters between the two time-points.Sensitivity analyses were also done in patients presenting with SBP reduction≥30 mmHg between baseline and follow-up TCD assessment; with SBP≥160 mmHg atbaseline TCD assessment; with ≤7 days-interval since symptoms-onset; with anischaemic lesion consistent with symptoms on magnetic resonancediffusion-weighted imagining (DWI).Reliability of repeated measures of relevant variables at baseline and one-monthfollow-up was expressed as intra-class correlation coefficient with 95%confidence interval (CI).To analyse the effect of changes between baseline and one-month follow-up inrelevant TCD parameters change on long-term risk of subsequent recurrent strokeor death, Cox regression analysis was used, with age, sex and SBP at baseline ascovariates.All analyses were performed using SPSS version 26 and Stata version 16.1., 779 (94.9%)attended the one-month follow-up clinic for a second TCD assessment; 82 patientswith ≥50% intraor extracranial stenosis were excluded. Demographic andclinical characteristics of the remaining 697 patients included in the analysis arereported in Of 821 eligible patients with an initial diagnosis of first-ever TIA/non-disablingstroke who had TCD in the rapid-access clinic p < 0.0001) at 1 month (133.7/17.4 mmHg), mainlyin patients who were hypertensive at baseline . Of all the TCD parameters, the only significant change observedbetween baseline and follow-up was an increase in EDV  and a decrease in RI , driven by hypertensive patients , with larger changes inpatients with blood pressure reduction between baseline and follow-up in the highesttertile (Supplementary Table 2). Changes in TCD parameters were unrelated togender (Supplementary Table 3).Blood pressure (both clinic-based and HBPM) and haemodynamic parameters at baselineand follow-up and changes between the two time-points, are shown in tertile . Inthe tertile . Therewtrend= 0.357; RI change–ptrend = 0.225), including 117 patients ≥80 (mean/SDage 84.43/3.71), where haemodynamic changes similar to those in the younger agegroups were observed, despite somewhat greater blood pressure decrease betweenbaseline and one-month follow-up (Supplementary Table 4).Changes in EDV and RI were consistent across age groups  andfollow-up . The EtCO2 change did not differ across gender (mean/SD EtCO2 change =0.25/0.61 KPa in men vs 0.24/0.63 in women p = 0.863) and age groups.Mean/SD EtCOBetween the first and the second assessment, the group of 180 patients on noantihypertensive treatment at baseline and follow-up displayed EDV changes rangingbetween −19.75 and 20 cm/s. In the 517 patients on antihypertensive medication, EDV changes ranged between−23.50 and 37.50 cm/s. Only two of these patients had an EDV decrease betweenbaseline and follow-up below −19.75 cm/s (−23.50 and −20.75 cm/s), both with PSV atbaseline suggestive of possible MCA stenosis, which resolved on subsequentassessment and was not demonstrated at the time of vascular imaging. These twopatients did not have any excess adverse events on long-term follow-up. In thesub-group with more intensive SBP reduction (≥30 mmHg), EDV changes ranged between−17.25 and 24 cm/s p-values in bold are statistically significant (p < 0.05).Supplementary Table 1), results were consistent when excludingpatients with an ultimate non-vascular diagnosis at one-month follow-up and afterexcluding three patients with recurrent ischemic stroke between baseline andfollow-up assessment. Haemodynamic changes were also consistent in patients withSBP≥160 mmHg at baseline, those with symptoms onset 7 days before baselineassessment or less  and those with an acute ischaemic lesion consistentwith symptoms on magnetic-resonance DWI. The largest absolute changes inhaemodynamic parameters were observed in the 100 patients with mean clinic SBPdecrease of 30 mmHg or more, with mean/SD increase in EDV of 2.49/7.47 cm/s(p = 0.001) and decrease in RI of −0.024/0.063(p < 0.0001) (Supplementary Table 1).In the other sensitivity analyses (p = 0.873).Increase in EDV at one-month follow-up was not associated with a higher risk ofrecurrent stroke or death on long-term (mean/SD = 4.31/1.84 years) follow-up and very old (≥80 years) patients. In fact, asignificant increase in TCD EDV was consistent across all age groups, with noevidence that older ages are at disproportionately higher risk of reduced velocitieswith intensive blood pressure reduction early after TIA/non-disabling stroke. Thisis a clinically important finding given that many elderly patients are treated inrapid-access TIA clinics and that there is some uncertainty around timing andtargets for blood pressure reduction in the context of secondary prevention ofstroke in this age group. the EDV increase and RI decrease observed in our study after blood pressurereduction suggest, in presence of constant proximal MCA calibre, there is a decreasein distal vascular resistance vessels. EDV increase has been shown to reflectincreased perfusion in the clinical setting of pharmacological cerebral reperfusionafter stroke, with even a small increase in early post-recanalisation EDV beingassociated with significant neurological and functional improvement, suggesting thatEDV is a clinically relevant marker of cerebral perfusion.As the autoregulatory response to blood pressure variations takes place predominantlyin small parenchymal vessels distal to the proximal MCA,Interestingly, absolute changes in EDV and RI were largest in patients withhypertension at baseline and in those with SBP reduction of 30 mmHg or more, with noevidence of disproportionate EDV decrease in any of these patients . Reducti such as patients with more recent symptoms-onset , or withDWI-positive lesions on MRI imaging.The direction and magnitude of haemodynamic changes were un-altered in oursensitivity analyses, including in patients who might be at higher risk of alteredcerebral autoregulation due to cerebral infarction,2, albeit small in absolute terms, might havecontributed to the increase in EDV between baseline and follow-up, and could partlyreflect a state of anxiety – with relative hypocapnia – in patients in the acutesetting, which was attenuated at 1 month follow-up. Indeed, there is a positive linear association between TCD velocities andpartial arterial CO2 pressure, which is made steeper by anxiety. However, the fact that TCD changes were only seen in hypertensive patientsmakes it unlikely that that they were entirely due to anxiety-related changes inEtCO2.The observed increase in EtCOThis study has several strengths. It is the first large study on cerebralhaemodynamic effects of blood pressure lowering in symptomatic patients soon afterTIA/non-disabling stroke, allowing detection of small physiological changes thatwould otherwise go overlooked. Importantly, we included a large proportion (abouttwo-thirds) of patients ≥65 years of age, 117 of whom ≥80, who were followed up4 weeks after the first assessment, when autoregulation is more likely to havesettled after a vascular event. It was a pragmatic, real-world study, conducted inan every-day clinical setting, therefore providing more clinically usefulinformation to clinicians than physiologically sophisticated studies removed fromroutine clinical conditions. However, TCD is an accurate and easily accessible method for functionalstudies of cerebral haemodynamics, 31 and a strong correlationbetween blood flow volume and TCD blood flow velocity in the proximal MCA has been demonstrated. Although it could be argued that pharmacologically induced blood pressurereductions could result in changes of MCA diameter, experimental studies suggest that any such effects are negligible in theproximal MCA, with changes confined to the smaller distal vessels. Moreover, minor changes in proximal MCA diameter would be unlikely to causeunacceptable discrepancy between velocity and flow in most cases. Furthermore, other imaging methods, including Xe inhalation method and single photon emission computed tomography arterial spin labelling magnetic resonance imaging, are less practical in large studies and more likely to lead to exclusion ofolder and frail patients. Our findings highlight the potential of TCD EDV and RI aspotential surrogate markers of cerebral blood flow in future studies and trialstargeting cerebral perfusion. Secondly, some antihypertensive medications have direct and specific effectson cerebral blood flow,35 but we were unable to assess this, as the majority of ourpatients were treated with multiple agents. Thirdly, although the magnitude anddirection of EDV changes between baseline and follow-up was consistent across allsensitivity analyses, they represent mean changes; we have however shown that therange of changes in the group of patients receiving pharmacological blood pressurelowering was similar to that of patients whose blood pressure was notpharmacologically reduced, with a shift towards higher value of EDV increase ratherthan towards EDV decrease. Lastly, these results cannot be generalised to patientswith significant intra/extracranial stenosis, who were excluded from the presentanalysis. Further studies are needed in this group of patients.However, our study also has some weakness. Firstly, we used TCD sonography, whichprovides a measure of blood flow velocity in the basal cerebral arteries rather thanof blood flow.In this study on patients without arterial stenosis, there was no suggestion on TCDsonography of decreased blood flow velocities associated to blood pressure loweringsoon after TIA and non-disabling stroke, irrespective of age, including elderly(65–79 years) and very old (≥80 years) patients. Rather, the observed EDV increaseand RI decrease suggest reduction in distal vascular resistance.Click here for additional data file.Supplemental Material, sj-pdf-1-eso-10.1177_23969873211039716 for Age-specificcerebral haemodynamic effects of early blood pressure lowering after transientischaemic attack and non-disabling stroke by Sara Mazzucco, Linxin Li, Iain JMcGurgan, Maria A Tuna, Nicoletta Brunelli, Lucy E Binney, Peter M Rothwell andon behalf of the Oxford Vascular Study Phenotyped cohort in European StrokeJournal


Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are a relatively novel class of drug for treating type 2 diabetes mellitus (T2DM) that inhibits glucose reabsorption in the renal proximal tubule to promote glycosuria and reduce blood glucose levels. SGLT2i has been clinically indicated for treating T2DM, with numerous recent publications focussing on both primary and secondary prevention of cardiovascular and renal events in Type 2 diabetic patients. The most recent clinical trials showed that SGLT2i have moderately significant beneficial effects on atherosclerotic major adverse cardiovascular events (MACE) in patients with histories of atherosclerotic cardiovascular disease. In this review and analysis, SGLT2i have however demonstrated clinically significant benefits in reducing hospitalisation for heart failure and worsening of chronic kidney disease (CKD) irrespective of pre-existing atherosclerotic cardiovascular disease or previous heart failure history. A meta-analysis suggests that all SGLT2 inhibitors demonstrated the therapeutic benefit on all-cause and cardiovascular mortality, as shown in EMPAREG OUTCOME study with a significant decrease in myocardial infarction, without increased stroke risk. All the above clinical trial recruited type 2 diabetic patients. This article aims to postulate and review the possible primary prevention role of SGLT2i in healthy individuals by reviewing the current literature and provide a prospective overview. The emphasis will include primary prevention of Type 2 Diabetes, Heart Failure, CKD, Hypertension, Obesity and Dyslipidaemia in healthy individuals, whom are defined as healthy, low or intermediate risks patients. SGLT2i is a novel class of medication that decreases plasma glucose concentration. The pharmacological action shows that a healthy individual will approximately filter 160–180g glucose daily from the glomerulus with almost 100% reabsorption via the proximal convoluted tubule (PCT), hence leaving almost no urinary glucose. Diabetic patients' glomerular filtration of glucose increased significantly to 180–240g daily above renal glucose threshold, leading to glycosuria. SGLT2i bind to SGLT2 receptors with an insulin-independent mechanism of action, further increasing glycosuria and consequently lowering plasma glucose concentration . SGLT2i The authors performed an extensive literature review using the following Medical Subject Headings (MeSH) terms including SGLT2i, guideline, safety, cardiovascular diseases, chronic kidney diseases, heart failure, hypertension, dyslipidaemias, obesity, chronic diseases and primary prevention. The review has identified 2185 publications related to SGLT2 inhibitors' safety, guidelines in different countries and potential preventive role in cardiovascular diseases, chronic kidney diseases, heart failure, hypertension, dyslipidaemias, obesity and chronic diseases. After scanning the titles and the abstracts to remove duplication, we have included 88 publications based on SGLT2 inhibitors' relevancy on the role of primary prevention by using the Oxford Equator PRISMA checklist to satisfy an evidence-based narrative review.In Australia, the Therapeutic and Goods Administration (TGA), has currently approved two SGLT2i use in Australia: dapagliflozin and empagliflozin . CanagliIn the United States of America, the Food and Drug Administration (FDA) has authorised the use of four SGLT2 inhibitors including canagliflozin, dapagliflozin, empagliflozin and ertugliflozin in treating T2DM patients. Recent guidelines by American Diabetes Association state that patients with high-risk or pre-existing atherosclerotic cardiovascular disease, or pre-existing kidney disease, or heart failure, we recommended SGLT2i as part of the glucose-reducing regimen irrespective of HbA1c control .In the United Kingdom and the European Union, SGLT2 inhibitors are approved as an add-on therapy for patients having high blood glucose levels despite being on metformin and insulin. They are, however, not recommended to be prescribed for patients with CKD due to decreased efficacy .In the European continent, SGLT2i is indicated in the 2019 European Society of Cardiology guideline as first-line therapy for patients with T2DM and established cardiovascular disease .In China there are three SGLT2 inhibitors that have been approved for use: dapagliflozin, empagliflozin and canagliflozin . SGLT2i There are numerous reports of potential safety issues associated with the use of SGLT2i including the rare but serious adverse events of diabetic ketoacidosis and necrotising fasciitis of the perineum. The report regarding the possible heightened risk of lower limb amputation and fracture with SGLT2i is conflicting.SGLT2i used as a monotherapy are all associated with a low risk of developing hypoglycaemia, and hypoglycaemia risk is raised when utilised as an add-on therapy with sulfonylurea or insulin , 9. NeveThe most well-documented adverse event of SGLT2i in comparison with placebo groups is mycotic infections, particularly amongst the female population , 16. IntThe widespread use of SGLT2i in recent years has been associated with a slightly increased risk of diabetic ketoacidosis. , 20 The Canagliflozin in clinical trial (CANVAS) increased the risk of toe and foot amputation  , as wellThe best practise of SGLT2i use for patients with kidney disease is debated . The useSGLT-2i did not seem to increase the overall risk of cancer in patients with T2DM. In terms of global use of common SGLT-2 inhibitors including canagliflozin, dapagliflozin and empagliflozin, most research showed that there were no direct links between SGLT2i use and overall cancer risk. Two reviews particularly reported for canagliflozin and empagliflozin, demonstrating contrasted trend of cancer risk with a statistically significant decreased risk of gastric cancer but increased bladder cancer risk , 37. DetApart from well-documented benefit in diabetic patients as a monotherapy or add-on therapy, more recent evidence demonstrated that SGLT2i reduced major adverse cardiovascular events (MACE) and hospitalisation for heart failure (HHF) , 43. SGLTaken together, evidence is mounting for reviewing the literature of SGLT2i use in both diabetic and non-diabetic population , so as tChronic Kidney Disease leads to many severe morbidity and mortality, with hypertension and diabetes being the commonest causes. Diabetic nephropathy is ranked the second in causing end-stage kidney disease in China, while the global incidence of diabetic microalbuminuria is 39% with the incidence of albuminuria being 3.1% annually . Thirty The mechanism of the reno-protective benefit of SGLT2i for diabetic patients has been proposed in a few recent studies –54 incluvia the mechanism of reducing the single nephron glomerular filtration rate (SNGFR) and thus preventing hyper-filtration. Of important note is that cessation of SGLT2 inhibitors will lead to SNGFR returning to its original level prior to commencing the SGLT2 inhibitors . Cardiovascular-related death, nonfatal cerebral infarction, and nonfatal myocardial infarction reduced by 14%, while the number of cardiovascular-related deaths reduced by 38%, as well as the number of hospitalised patients with heart failure reduced by 35%, and its mortality rate reduced by 32% in the SGLT2i group in comparison to the placebo group. Furthermore, the follow-up study demonstrated the ongoing significant cardiovascular benefit of empaglifozin from 30 to 90 days of treatment, as well as with the extension of treatment time compared with the placebo group. In the Canagliflozin Cardiovascular Assessment Study (CANVAS) trial, 10,142 patients with T2DM and high cardiovascular risk with 34.4% without prior CVD were randomly assigned to receive canagliflozin or placebo, with MACE being reduced by 14% (p = 0.02), but no significant reduction in individual components of the composite outcome  0.1 , 63–65.  outcome . A signin = 2,181, 49.6%), showed that canagliflozin significantly decreased the risk of MACE by 20% (p = 0.01) with consistent reduction in both primary and secondary prevention group  (p < 0.001)  trial in patients without CVD (on 0.25) . Anotheron 0.25) , 51–53. < 0.001)  The mech< 0.001) , 65, 67.Taken together, SGLT2i has strong evidence of prevention of MACE and HHF in diabetic patients, whereas the evidence is not consistent with the low-risk non-diabetic patients. It is worthy to proceed with a RCT to examine the preventive role of SGLT2i in non-diabetic low-risk population, especially the prevention of MACE and cardiac death as being observed in DAPA-HF trial .via the inhibition of SGLT2i on sodium reabsorption, resulting in natriuresis, osmotic diuresis and subsequent BP reduction by plasma and extracellular volume contraction (Recent review on SGLT2i BP lowering effects in diabetic patients with hypertension  has demotraction . BP redutraction . In simitraction , 72, SGLtraction , 73. BP traction , and BP traction , but redtraction , many cltraction . Furthertraction , 76. OneThere were inconsistent results in numerous clinical trials with diabetic patients regarding the effects of SGLT2i on dyslipidaemia. One study showed that SGLT2i raised HDL cholesterol and reduced triglycerides levels , howevervia glycosuria and negative energy balance, thereby leading to significant weight loss (Obesity is well established to be an independent risk factor for cardiovascular disease . SGLT2i ght loss . SGLT2i ght loss . This reght loss , 27, 82.ght loss . Howeverght loss . In a MRght loss . In anotght loss , weight ght loss , indicatght loss . There ight loss . Most ofIn summary, SGLT2 inhibitors reduce MACE in patients with known atherosclerotic cardiovascular disease, cardiovascular risk factors including hypertension, dyslipidaemia, overweight/obesity, and have a profound effect on preventing hospitalisation for heart failure, as well as reducing the risk of worsening estimated glomerular filtration rate, end-stage kidney disease, or renal death. However, the majority of these evidences concerned diabetic patients or high CVS risk patients with only small numbers of low-risk/heathy individuals in studies of non-diabetic, coronary arterial diseases and heart failure patients. Taking all the evidences together, there is a need for consideration of SGLT2i as a potential agent for primary prevention clinical trial in low-risk of cardiovascular and renal diseases or even healthy population with research design focusing on ensuring its safety and minimising potential side effects. A carefully-designed protocol for this SGLT2i double-blind randomised controlled primary prevention trial should answer the ultimate goal of exploring its prevention role in reducing events and improving quality of life in the healthy individual.DX, OC, CW, CH, JA, DY, XL, WC, YL, CR, and HX reviewed the final manuscript. DX, DY, XL, WC, YL, CR, and HX designed the manuscript. DX, OC, CW, and CH drafted the initial manuscript. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. 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There are unexplained geographical variations in the incidence of kidney cancer with the high rates reported in Baltic countries, as well as eastern and central Europe. Having access to a large and well-annotated collection of “tumor/non-tumor” pairs of kidney cancer patients from the Czech Republic, Romania, Serbia, UK, and Russia, we aimed to analyze the morphology of non-neoplastic renal tissue in nephrectomy specimens. By applying digital pathology, we performed a microscopic examination of 1012 frozen non-neoplastic kidney tissues from patients with renal cell carcinoma. Four components of renal parenchyma were evaluated and scored for the intensity of interstitial inflammation and fibrosis, tubular atrophy, glomerulosclerosis, and arterial wall thickening, globally called chronic renal parenchymal changes. Moderate or severe changes were observed in 54 (5.3%) of patients with predominance of occurrence in Romania  and Serbia  in reference to those from Russia. Further adjustment for comorbidities, tumor characteristics, and stage did not change risk estimates. In multinomial regression model, relative probability of non-glomerular changes was 5.22 times higher for Romania and Serbia compared to Russia. Our findings show that the frequency of chronic renal parenchymal changes, with the predominance of chronic interstitial nephritis pattern, in kidney cancer patients varies by country, significantly more frequent in countries located in central and southeastern Europe where the incidence of kidney cancer has been reported to be moderate to high. The observed association between these pathological features and living in certain geographic areas requires a larger population-based study to confirm this association on a large scale.The online version contains supplementary material available at 10.1007/s00428-020-02986-3. Worldwide, kidney cancer was reported as the 9th most common malignancy in men and 14th in women in 2018, with an estimated 136,515 and 67,424 new cases in Europe and North America respectively. There is considerable geographic variation in the incidence of kidney cancer; the reason for that is unknown. The highest incidence rates are reported in Baltic countries, as well as Central and Southern Europe, with age-standardized incidence rates of 16.8 in Belarus, followed by Latvia (15.2), Lithuania (14.8), Czech Republic (14.7), and Estonia (14.6) [Previous data indicate that non-neoplastic kidney tissues in nephrectomy specimens, removed for renal neoplasms or advanced renal diseases, are rarely normal and often show variable levels of pathological changes such as glomerular abnormalities, diabetic or hypertensive nephropathies, and chronic pyelonephritis. It is shown that 5 to 25% of RCC patients have varying pathologies of chronic kidney disease and those with normal renal function are more likely to develop chronic kidney disease after nephrectomy. Such changes may cause impairment of renal function and reduce the patient’s quality of life . Chronichttp://www.cng.fr/cagekid/). This collection comprises more than 2000 frozen “tumor/non-tumor” pairs with annotated clinico-epidemiological data of kidney cancer patients.During 2007 to 2016, the International Agency for Research on Cancer (IARC)/WHO conducted hospital- and population-based, multicentric case-control studies in the Czech Republic, Romania, Serbia, and Russia (K2 study) to recruit incident cases with a kidney cancer diagnosis for the purpose of a better understanding of the epidemiology, etiology, and genomics of renal cancer. In parallel, incident kidney cancer cases were recruited in the United Kingdom (UK) by the Leeds Multidisciplinary Research Tissue Bank. Both collections were used in the Cancer Genomic of Kidney (CAGEKID) project  throughout the participating countries. Immediately after partial or radical nephrectomy, in addition to tumor tissue, one piece of non-neoplastic tissue was collected with the following specifications: from the renal cortex, distant from tumor, and at least 5 mm in the largest diameter. However, the exact distance of the collected non-tumor tissue from tumor was not recorded. All of the collected tissues were snap-frozen and stored in liquid nitrogen or directly immersed in RNAThe current study took shape accidentally and following some specific observations. We at IARC, responsible for DNA/RNA extraction for the CAGEKID study, noticed lower RNA quality in non-tumor tissues compared to tumors. While looking for the reason behind this observation and finding none, we decided to have a second look at the microscopy of non-tumor tissues to understand if there could be any morphological finding relevant to this observation. BAA, pathologist at IARC, performed this examination and evaluated and recorded the observed features, as detailed as possible. The pathologist was blinded to tumor type, epidemiological data, country of residence, and results of RNA quality. This first essay on 626 tissues ended to find nothing that could explain the quality of RNA. Instead, we found some pathologies that our preliminary statistical analyses showed them occurring significantly limited to specific countries. These unexpected but interesting results led us to expand our work to a larger number of available tissues in our biorepository and to re-evaluate them altogether under one project and by applying more rigorous statistical analyses. Below, we report the design and the results of this work.We selected 1045 non-neoplastic kidney tissues based on the availability of at least one hematoxylin and eosin (H&E) stained slide, irrespective of the tumor type or the country of recruitment. High-resolution whole slide images were used for digital microscopy by one pathologist (BAA), blind to the type and status of tumor, demographic and clinical data, country of recruitment, or laboratory results. We first evaluated the composition of renal parenchyma, and if purely from cortex or containing medulla as well. Four components of renal cortex and their pathological changes were examined: renal glomeruli and the presence of various degrees of glomerular sclerosis (GS); renal tubules and the presence and severity of atrophy; presence and severity of interstitial fibrosis ; presence, severity, and type of inflammation; and also blood vessels’ structure. All the observed changes were recorded. We then qualitatively scored the intensity of these changes, which were collectively called chronic renal parenchymal changes (CRPC), from none to severe as follows: none, if no significant pathological changes were observed, and mild, moderate, and severe if any or a complex of parenchymal changes were seen with +, ++, or +++ intensity, respectively. We then used the proposed scoring method by the International Society of Nephrology (ISN) to report the microscopic findings of the non-neoplastic renal tissues in native kidney biopsies. In ISN scoring, the severity of changes in each renal parenchymal component is scored quantitatively, and by adding the scores the severity of chronic changes are graded into minimal, mild, moderate, and severe . By applDependent on our findings, we categorized outcomes into two main groups: those with none–mild CRPC versus those with moderate–severe CRPC. Demographic variables were then categorized and compared between two outcomes including country of recruitment, age at diagnosis, body mass index (BMI) at diagnosis, tobacco smoking status, and alcohol consumption habit. Furthermore, we added variables that could have a negative impact on our collection protocol such as tumor size and stage, surgical approach , and percentage of the medulla (the predominance of medulla was considered as a possible indicator of full occupation of cortex by tumor). Kidney-related diseases or medical conditions that could potentially confound the relation between CRPC and demographic variables were analyzed, including self-reported history of hypertension, diabetes mellitus, nephrolithiasis, chronic kidney disease, and ever use of non-steroidal anti-inflammatory drugs (NSAIDs). Logistic regression models were used to calculate unadjusted and adjusted odds ratios (ORs) and 95% confidence intervals (CIs). In all analyses, unexposed groups were the reference. For numerical variables, lowest category was considered as a reference. To study the association between country and CRPC, we used three models to include co-variables for adjustment: model 1 includes age (5 levels of age groups), sex, and percentage of the medulla (4 categories); in model 2, we added stage of the tumor (4 levels) and tumor size ( 4 categories); in model 3, we added 3 binary variables including history of diabetes mellitus, hypertension, and NSAID use to model 1.We evaluated the performance of our scoring by comparing it with the ISN scoring method. Also, we used multinominal regression analysis to compare geographical residence (as predictor) association with the presence of individual components of CRPC without applying any score which included: only GS and at any level, pathologies limited to IFTA with no GS, presence of both GS and IFTA, and absence of any pathological change. Age, gender, and presence of inflammation were included in the model.P = 0.001). The proportion of both glomerular and tubular components of CRPC increased by age , the UK (Leeds), Russia (Moscow), and Serbia (Belgrade). Clear cell RCC was the most common histological type of RCC in the entire examined patients (84.0%), followed by papillary RCC 7.3%). Other tumor types included chromophobe RCC, collecting duct carcinoma, unclassified RCC, and oncocytoma, which altogether comprised 8.7% of the total examined cases. The proportion of major RCC histological types did not vary across CRPC scores (Table %. Other P = 0.20). Among cases with predominant IFTA, surgical approaches were 7.8% and 8.8% for partial and radical nephrectomy (P = 0.72).Table P = 0.4). Self-reporting of diabetes mellitus was recorded in 12.0% of patients. Similar proportion of our two CRPC groups did not report history of diabetes (73.0% vs. 70.0%). Although percentage of missing data for diabetes was significantly higher in none–mild category, there was a trend towards less cases with diabetes among moderate–severe CRPC (P = 0.03). In our series, 121 patients reported a history of diabetes . A total of 511 patients had a history of hypertension . NSAIDs users were defined as those who take NSAIDs at least once a week for a year. Both groups of CRPC showed a similar proportion of non-users (68.5% vs. 70.6%) while missing data amongst advanced CRPCs was less than half of none–mild group (7.0% vs. 17.0%). After excluding missing data, NSAIDs use was less common among moderate–severe CRPC group than none–mild one (P = 0.04).Since medical conditions such as hypertension and diabetes mellitus are common in RCC patients and could lead to morphological changes in renal parenchyma, we evaluated the association of the observed CRPC with medical conditions and risk factors for RCC. Almost half of RCC patients reported history of hypertension in this study. In spite of variation in prevalence of hypertension across countries, hypertensive patients were equally distributed among CRPC categories , 100% specificity (95% CI: 87.2%–100%), and 0.91 area under ROC (95% CI: 0.83–0.99)  who was also member of the expert pathology panel of the CAGEKID study. We acknowledge the importance of long-time expertise in uro-nephro pathology to examine renal tissues, although our findings show that the level of expertise might not differentially affect the classification of tissues into CRPC and otherwise between countries and it is unlikely that the observed difference is due to this aspect of study design.Previous reports on the microscopic examination of non-neoplastic kidney tissue in cancer-related nephrectomies have shown that the pressure effect from the adjacent tumor causes pathologic morphological and clinical features while this effect reduces with distance. Azhar et al. showed that the severity of pathological findings such as inflammation, nephrosclerosis, and glomerulosclerosis decreased from severe to mild at 1 to 5 mm distance from tumor . StudiesTo address the possibility of tumor pressure effect being the origin of our observations, we first relied on our harmonized sample collection procedure in which collection of non-neoplastic tissues as distant as possible from tumor, and from renal cortex has been emphasized. Based on these guidelines, we expect that these tissues were collected distant from tumor, particularly in more than 5 mm . The observed association between CRPC and country of origin could not be entirely explained by possibility of collecting nontumoral tissues closer to tumor in Romania and Serbia, notably because we observed lower number of tumors larger than 10 cm in these countries. Also, choice of surgical method and tumor stage proportion of cases with GS or IFTA was similar between patients with and without CRPC. In addition, all of the examined non-neoplastic tissues were free of tumor in microscopic examination. Adjusted models for confounders such as tumor size and type of nephrectomy did not change the initial risk estimates. These findings support the idea that the observed CRPC are not caused by the pressure effect from tumor and are independent events.Hypertension and diabetes mellitus are among the main causes of chronic and end-stage renal disease and lead to pathological parenchymal features mainly in arterioles and glomerular capillaries. For precise evaluation of these changes, special stains such as periodic acid-Schiff and methenamine silver should complete the H&E staining. Due to the frozen nature of our samples, we could not perform special stains. Instead, we applied strict criteria to overcome this limitation. We categorized all of the mild changes with those with no significant pathological changes, in the group of none–mild to avoid overestimation of the observations and to cover any possibility of missing some diagnostic features due to the use of frozen tissues. Our qualitative scoring was not only correlated with the quantitative one by ISN but also lower sensitivity in this method ensures us that our estimated risk might be even underestimated due to misclassification of true positive ones among CRPC negative group. In addition, lack of hypertension and diabetes mellitus history was similarly reported in the both groups of none–mild and moderate–severe CRPC. When adjusted for these factors, the odds estimate did not change. Self-reported hypertension and diabetes mellitus were less frequent among Romanians. As a result, these two common medical conditions are more frequent in our reference population (Russians) and cannot fully explain the higher prevalence of CRPC in patients from the Czech Republic or Romania and Serbia.http://www.healthdata.org/gbd), and WHO data observatory (https://www.who.int/gho/en/), the prevalence of chronic kidney disease (CKD) in the Czech Republic, Romania, and Serbia is 13.5%, 12.3%, and 13.3% respectively. In our study, the report of medical history of CKD in the Czech Republic and Romania with 426 and 128 recruited cases was 3.5% and 3.9%, respectively. The prevalence of CKD in our study group from these two countries is lower than the reported country prevalence with no statistical difference between two countries. Among 31 Serbian cases, only 6 reported a history of CKD. Due to the modest sample size, we combined patients from Serbia and Romania. CKD prevalence in the combined group reaches to 6.9%. There is no statistical difference between CKD prevalence in the Czech Republic versus combined Romania and Serbia .The significant presence of CRPC in Romania and Serbia is of particular interest. Based on the 2019 Global Burden of Disease (GBD) study database  that might lead to answer some of the questions in this regard.We showed that IFTA is the main driver for the observed difference between the occurrence and severity of CRPC across study regions. Interstitial fibrosis and inflammation, with tubular atrophy, were the predominant features and glomerular and vascular changes seem to stem from the interstitial disease. These features are more suggestive for a chronic interstitial nephritis (CIN) pattern. CIN is a nonspecific diagnosis and identification of a specific reason causing it is not based on light microscopy only and needs accurate clinical history and imaging studies, the elements that are missing in our study. Chronic pyelonephritis, analgesic nephropathy, and Balkan endemic nephropathy (BEN) are among the most important specific reasons leading to CIN. BEN was first reported in the 1950s as a progressive renal disease in the form of chronic interstitial nephritis affecting the people living in the Balkan Peninsula along the tributaries of the Danube River in Bosnia and Herzegovina, Bulgaria, Croatia, Romania, and Serbia. Data support the etiologic role of dietary exposure to aristolochic acid (AA) in both BEN and Chinese herbs nephropathy. The association of AA nephropathy with urothelial carcinoma of the upper urinary tract is shown but such a link with RCC is not reported –16. We h in them . Eight oTo our best knowledge, this study is unique and the first one to report pathological changes in non-neoplastic kidney tissues regarding both sample size and geographical diversity of the patients from countries with variable incidence of RCC. That is also the first report from Serbia where we observed the highest proportion (13.3%) of moderate–severe changes in renal parenchyma.Additionally, this is the first report relying on frozen tissues for detailed microscopic examination. In the current era of a growing number of molecular studies based on the use of frozen tissues to optimize the quality of the high throughput technologies, it is critical to assess the reliability of morphological examination of frozen tissues. It was worth mentioning that properly preserved frozen tissues have acceptable quality for microscopic examination, although one should be aware of their limitations. At IARC, we are experienced in treating and evaluating variable kinds of frozen tissues and performing the routine microscopic evaluation of frozen tissues for the purpose of genomic studies.Our study has some limitations. Undoubtedly, we could have better verified our findings on formalin-fixed paraffin-embedded (FFPE) tissues that are the gold standard in diagnostic pathology. However, we did not have access to FFPE blocks because of the retrospective nature of the study, collection of samples in more than 10 years ago, and multicentric nature of the collection that complicates the access to the pathology archives of the hospitals. The main limitation of use of frozen tissues in this study is inability to apply special stains, which are part of routine practice of nephropathology, particularly to evaluate glomerular and vascular changes. However, H&E is good enough for the microscopic evaluation of interstitial and tubular changes, the predominant observed pathological features.Additionally, our study suffers from missing clinical and laboratory data of renal function, because it is based on retrospective collection that was designed for another aim. However, our findings bring the first level of information and urge for properly designed studies to answer the raised questions.In conclusion, we report renal parenchymal pathologies in non-neoplastic kidney tissue of RCC patients in central and southeastern Europe with the predominance of CIN pattern rather than primary glomerular disease. We show that these findings are unlikely to be due to sampling method or pressure effect of the tumor alone. The observed association between CRPC and living in certain geographic areas requires larger population-based studies to confirm this association in large-scale and designed studies for this aim.ESM 1(PPTX 7.17 mb)ESM 2(DOCX 15.1 kb)