Obesity is associated with several neurohumoral changes that play an essential role in organ damage. Increased arterial stiffness causes functional vessel wall changes and can therefore lead to accelerated target organ damage as well. Whether obesity causes an independent increase in central arterial stiffness is, however, not yet fully known.One hundred thirty-three patients  were included. Body Mass Index (BMI) was defined as body weight in kilograms, divided by the square of body height in meters. Chronic Kidney Disease Epidemiology Collaboration creatinine 2009 equation was used to estimate the glomerular filtration rate (eGFR). Non-invasive applanation tonometry was used for arterial stiffness measurements . All patients underwent coronarography.2, eGFR 75.5 ± 17.2 ml/min/1.73 m2 and ankle-brachial index (ABI) 1.0 ± 0.1. Their arterial stiffness measurements showed mean carotid-femoral pulse wave velocity (cfPWV) 10.3 ± 2.7 m/s, subendocardial viability ratio (SEVR) 164.4 ± 35.0%, and pulse pressure (PP) 47.8 ± 14.5 mmHg. Spearman's correlation test revealed a statistically significant correlation between BMI and SEVR , BMI and cfPWV  and between BMI and PP . Multiple regression analysis confirmed an independent connection between BMI and cfPWV  and between BMI and SEVR . There was no association between BMI and kidney function, ABI, or coronary artery disease.The mean age of our patients was 65.0 ± 9.2 years. Their mean BMI was 28.5 ± 4.4 kg/mIncreased BMI is independently associated with augmented central arterial stiffness and reduced subendocardial perfusion but not with coronary artery disease, kidney function, or ABI. Obesity is a complex and multifactorial disease, affecting nearly one-third of the world’s population. The epidemiologic burden of obesity is increasing and it is postulated that by 2030, almost 40% of all adults will be either overweight or obese .2 indicate that a person is overweight. World Health Organization (WHO) defines obesity as excessive fat accumulation that can impair health and is diagnosed at BMI ≥ 30 kg/m2 [Body Mass Index (BMI) values between 25 and 30 kg/m30 kg/m2 .Obesity substantially increases the risk of metabolic diseases (type 2 diabetes mellitus and fatty liver disease), cardiovascular diseases , musculoskeletal disease (osteoarthritis), Alzheimer dementia, chronic kidney disease (CKD), obstructive sleep apnea, and several malignancies  . BesidesArterial stiffness develops from an intricate interaction between structural and functional vessel wall alterations, which are inherently linked to the process of atherosclerosis . VasculaObesity is an important predictor of atherosclerosis . BesidesThe aim of the study was to assess whether increased BMI can lead to increased arterial stiffness and if this connection is independent of traditional atherosclerosis risk factors. Additionally, we wanted to determine if there was any connection between BMI and target organ damage, such as coronary artery disease (defined by coronarography), peripheral arterial perfusion , and kidney function (determined by estimated glomerular filtration rate (eGFR)).st, 2016, and February 1st, 2020, due to planned elective coronarography .In our cross-sectional cohort study, 133 patients were included. All patients were hospitalised at the Department of Cardiology and Angiology at the Clinic for Internal Medicine, University Medical Centre Maribor between March 1Exclusion criteria for the study were pregnancy, active malignancy at the time of the study, and age under 18 years. Both atrial fibrillation and aortic stenosis can impact peripheral pulse wave readings and arterial stiffness measurements; patients with these two pathological entities were therefore also excluded from the study .The patient’s medical history along with comorbidities and prescribed medications at the time of inclusion in the study was recorded.2.BMI was calculated as the ratio between body weight in kilograms and height in squared meters and was expressed in kg/mBefore coronarography, patients had their peripheral blood drawn. Analysed laboratory values included serum haemoglobin (g/L), serum lipid profile , high-density lipoprotein (HDL) and triglycerides, all values were expressed in mmol/L), creatinine (umol/L), cystatin C (mg/L), and N-terminal pro-hormone beta natriuretic peptide .Ankle-brachial index (ABI) was measured by using a previously validated, automated non-invasive waveform analysis device  . Blood pThe glomerular filtration rate was estimated (eGFR) by using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2009 creatinine equation.All patients signed a written informed consent prior to inclusion in the study.The National Ethics Committee approved the study (N°0120–32/2017/4). The study adhered to the Declaration of Helsinki and was performed per Good Clinical Practice standards.Arterial stiffness was measured at the Department of Dialysis, Clinic for Internal Medicine, University Medical Centre Maribor. Non-invasive applanation tonometry was employed to obtain these measurements . All the measurements were performed by two examiners , between 10 and 12 AM, from Monday to Friday, before coronarography.Each patient waited 5–10 min in a supine position before the measurements and all electronic gadgets and mobile phones were turned off during the study to prevent distortions in the obtained data. All patients abstained from coffee, cigarettes, heavy meals, and exercise at least 12 h before.Pulse wave analysis (PWA) was performed on the radial artery. Pulse pressure (PP) was defined as the difference between systolic and diastolic blood pressure. Augmentation pressure (AP) was the difference between the first and second systolic peaks. The augmentation index (AIx) was calculated as the ratio between PP and AP and it was also normalised to a heart rate of 75 beats per minute (AIx@75). The ejection duration (ED) was defined as the duration of the left ventricle systolic ejection. Subendocardial viability ratio (SEVR) was obtained from the ratio between the diastolic and systolic time index .All the measurements had to fulfil quality criteria to be included. Quality indices were: operator index ≥ 80%, average pulse height ≥ 80%, pulse height variation ≤ 5%, and diastolic variation ≤ 5%.Carotid femoral pulse-wave velocity (cfPWV) was defined as the pulse wave distance between the carotid and femoral artery, divided by pulse transit time . A subtracted carotid-femoral distance was used —) . Each paFor statistical analysis, Statistical Package for Social Sciences version 28.0 was used . Basic descriptive statistics were used for continuous variables (mean ± SD). Categorical variables were expressed with frequencies and percentages.The distribution of variables was tested with the Shapiro–Wilk test. Due to the non-normal distribution of our variables, non-parametric tests were used, such as Spearman's correlation test and one-way analysis of variance (ANOVA).p-value of < 0.05 was defined as statistically significant.Multiple regression analysis was performed with SEVR, cfPWV, and PP as dependent variables, and BMI, systolic blood pressure, diabetes, age, hyperlipidemia, and eGFR as independent variables. Additionally, BMI groups were created by using quartiles, and the differences between BMI groups were tested by using ANOVA and Chi-squared test. For all tests, a n = 105, 78.9%), hyperlipidemia , diabetes mellitus type 2 , heart failure , CKD  and peripheral arterial disease .84 patients (63.2%) were male. The most common comorbidities were arterial hypertension , statins , beta-blockers , angiotensin convertase inhibitors , diuretics , calcium channel blockers , angiotensin II receptor blockers  and alfa channel blockers . Seven patients (5.3%) were receiving aldosterone antagonists. The most commonly prescribed peroral antidiabetic therapy was metformin , ten patients (7.5%) had been prescribed insulin.Most commonly prescribed medications were acetylsalicylic acid (2 (range 18.9–42.5), and the mean eGFR was 75.5 ± 17.2 ml/min/1.73 m2 (range 6–90). All the other demographic and anthropometric data and laboratory values are presented in Table The mean age of our patients was 65.0 ± 9.2 years (range 27–82), the mean BMI was 28.5 ± 4.4 kg/m2 range 8.9–42.5,Arterial stiffness measurements are presented in Table Coronarography showed normal coronary angiogram in 43 patients (32.3%), 24 patients had one-vessel coronary artery disease (18.0%), 28 patients had two-vessel coronary artery disease (21.1%) and 38 patients had three-vessel coronary artery disease (28.6%).Comparing comorbidities, prescribed medications, BMI and arterial stiffness parameters between patients with different degrees of coronary artery disease showed no differences between groups. Comparison in arterial stiffness parameters in patients with different degrees of coronary artery disease is presented in Table r = -0.193, p = 0.026), cfPWV  and PP . No correlation was found between BMI and ABI values or between BMI and eGFR. No correlation was found between BMI and coronary artery disease either.BMI showed statistically significant correlation with SEVR (p = 0.044) and between BMI and cfPWV . Age also correlated with SEVR , cfPWV  and PP . No other associations were observed.Multiple regression analysis was performed to determine whether the correlation between BMI and several arterial stiffness parameters was independent of traditional atherosclerosis risk factors. Dependent variables were SEVR, cfPWV, and PP and independent variables were eGFR, age, diabetes mellitus, hyperlipidemia, BMI, and systolic blood pressure. A statistically significant and independent association was found between BMI and SEVR   and reduced SEVR. This association was present even in the absence of any structural or functional left ventricle adaptations and also in the absence of macrovascular coronary artery disease. The authors concluded that SEVR was a reliable marker of microvascular dysfunction [There have been some reports on the association between subendocardial perfusion and obesity. and SEVR . In a stnd cfPWV . Similarht peers . SEVR isht peers . It is aht peers . In a stfunction . As evidfunction . These fPetersen et al. found that even a modest decrease in body weight improved central arterial stiffness parameters [According to studies, increasing BMI is associated with decreasing arterial compliance, resulting in increased PP . This warameters , 40. Simrameters . The imprameters , 43. Evirameters . Additiorameters . It appeOur study had several limitations. The design of the study was imperfect in the sense that only patients with a high probability of cardiovascular disease were included. The study was not prospective and randomized, follow up measurements would be useful to assess the changes in arterial stiffness parameters during time in patients with different BMI. lso, only Caucasian patients were included, introducing racial bias into the results of the study. We did not perform definitive testing for microvascular coronary artery disease (scuh as coronary blood flow reserve with coronarography) and we also did not test for sensitive markers of inflammation, for example, high-sensitivity C-reactive protein. It would be sensible to perform additional research on a more diverse population and patients with different baseline cardiovascular risk profiles. Additionally, the inclusion of coronary blood flow reserve measurements, high-sensitivity C-reactive protein, and perhaps even echocardiography with strain measurements , would greatly improve our understanding of obesity-caused changes in vascular and myocardial function.We believe that the results of our study, underlined with multifactorial analysis and the use of both non-invasive and invasive methods are important, and will hopefully inspire more researchers to perform additional studies on arterial stiffness changes in patients with increased BMI.Increased BMI is independently associated with increased central arterial stiffness, even in the absence of clinically detectable target organ damage.


Kidney disease is a rare manifestation of ankylosing spondylitis (AS) and its pathological alterations remain poorly described. The aim of this study was to investigate the clinical presentation and pathological alterations on kidney biopsy of AS patients and review and discuss the current literature on the issue.We retrospectively studied the clinical presentation and kidney pathological alterations of 15 Caucasian AS patients submitted to kidney biopsy between October 1985 and March 2021.Patients were predominantly male (66.7%) with median age at the time of kideney biopsy of 47 years [IQR 34 - 62]. Median serum creatinine at presentation was 1.3 mg/dL [IQR 0.9 - 3] and most patients also had either proteinuria (85.7%) and/or hematuria (42.8%). The most common indication for kidney biopsy was nephrotic syndrome (33.3%), followed by acute or rapidly progressive kidney injury (20%) and chronic kidney disease of unknown etiology (20%). Chronic interstitial nephritis (CIN) (n=3) and AA amyloidosis (n=3) were the most common diagnosis. Others included IgA nephropathy (IgAN) (n=2), focal segmental glomerulosclerosis (n=2), membranous nephropathy (n=1), and immune complex-mediated membranoproliferative glomerulonephritis (IC-MPGN)(n=1).We present one of the largest series of biopsy-proven kidney disease in Caucasian AS patients. We found a lower prevalence of IgAN than previously reported in Asian cohorts. We found a higher prevalence of CIN and a lower prevalence of AA amyloidosis than that described in previous series of Caucasian patients. We also present the first case of AS-associated IC-MPGN. Patients can also experience peripheral arthritis as well as extra-articular manifestations, being the most common acute anterior uveitis (26%), psoriasis (9%), and inflammatory bowel disease (7%). AS has been associated with an increased risk of kidney disease compared to the general population, which may be an overlooked extra-articular manifestation in AS patients. The exact mechanism of kidney disease remains poorly understood as kidney biopsy results are only rarely reported. We present a case series of 15 Caucasian patients with AS submitted to kidney biopsy and provide a review and discussion of the current literature on renal manifestations of AS.Ankylosing spondylitis (AS) is an autoimmune-mediated axial spondyloarthropathy that affects primarily spinal and sacroiliac joints. It has a male predominance and its onset peaks in early adulthood. The most common manifestations include inflammatory back pain and progressive spinal rigidity leading to fusion of the spine and immobilityWe retrospectively studied renal biopsies of 15 patients with the diagnosis of AS received at our laboratory from October 1985 to March 2021. Histologic diagnosis was reviewed, as were serum creatinine (sCr), urinalysis, and 24-h proteinuria at the time of biopsy. When available, other relevant clinical data were collected.Proteinuria was defined as protein urinary excretion of more than 300 mg/24h and hematuria as presence of more than five erythrocytes per high power field (400x) on microscopic urine examination. Nephrotic syndrome was assumed whenever serum albumin was <3.5 g/dL with protein excretion of >3.5 g/24h.Renal biopsy specimens were examined by light microscopy (LM) and immunofluorescence (IF). LM analysis was performed after staining with hematoxylin and eosin (HE), periodic acid Schiff (PAS), periodic acid methenamine silver (PAM), Masson’s trichrome, and Congo-red. IF was performed in frozen sections (or in paraffin fragments after protease digestion as needed) using fluorescein isothiocyanate conjugated antisera to human immunoglobulins , light chains (λ and κ), complement , and fibrinogen. Amyloid substance was characterized using immunofluorescence or immunochemistry staining for SAA or κ and λ light chains.2 (standard deviation ±41mL/min/1.73m2) and most patients also had either proteinuria (86%) and/or hematuria (43%). The most common indication for kidney biopsy in our cohort was nephrotic syndrome , followed by acute or rapidly progressive kidney injury  and chronic kidney disease of unknown etiology .All patients were Caucasian and the majority (68%) was male with median age of 47 years (interquartile range [IQR] 34 to 62 years) and 10 years of median duration of the disease at the time of kidney biopsy (IQR 6 to 15 years). Only one patient was known to have a previous extra-articular manifestation (cutaneous psoriasis) and most patients had been treated with non-steroidal anti-inflammatory drugs (NSAID)  and/or Sulfasalazine  for AS. Median sCr at presentation was 1.3 mg/dL (IQR 0.9 to 3 mg/dL), mean estimated glomerular filtration rate (CKD-EPI) was 60mL/min/1.73mPathological diagnosis and clinical presentation of patients are described in A 63-year-old man with past medical history of AS diagnosed at 17 years of age, poorly controlled hypertension, and obesity was referred to the nephrology department for impaired kidney function with sCr of 1.6 mg/dL. Usual medication consisted in olmesartan, aliskiren, amlodipine, hydrochlorothiazide, fenofibrate, and allopurinol without recent changes or over-the-counter medications. Despite having controlled AS symptoms at the time of referral with no need for therapy, the patient had previous history of sulfasalazine and NSAIDs use. Aliskiren was suspended and carvedilol was initiated for better control of hypertension. Complementary studies revealed subnephrotic proteinuria (0.9g/24h), normal urinary sediment, and an erythrocyte sedimentation rate (ESR) of 56 mm/h. Immunologic studies and serum electrophoresis were unremarkable as were hepatitis B (HBV), C (HCV), and human immunodeficiency (HIV) virus serologies. For the next 6 months, the patient evolved with progressive kidney impairment reaching a sCr of 3 mg/dL. Kidney biopsy was performed and revealed 90% of interstitial fibrosis with tubular atrophy and an area of inflammatory infiltrate, consistent with CIN . As othe reported the case of a 78-year-old woman with a seronegative polyarthritis evolving for 10 years and corticoid-induced diabetes mellitus who presented to the nephrology department for NS . She also complained of constitutional symptoms, diarrhea, and inflammatory arthralgia. Usual medication consisted in methotrexate, deflazacort, esomeprazole, tapentadol, folic acid, and calcium carbonate plus cholecalciferol and insulin. Despite the main complaint was of peripheral arthritis, the patient also described a lower back pain. Bilateral sacroiliitis on image studies together with a positive HLA-B27 antigen made the definitive diagnosis of AS. Complementary studies revealed elevated ESR (117 mm/h) and C-Reactive Protein (CRP) (77 mg/L) and slight microscopic hematuria. Occult neoplasia, infection, and autoimmunity were excluded and a kidney biopsy was performed. Light microscopy showed amorphous deposition in the mesangium and small arterioles of a material that was Congo-red positive and showed apple-green birefringence under polarized light. Immunofluorescence was positive for AA protein and the definite diagnosis of AA amyloidosis was made. Similarly, AA amyloidosis was also found on intestinal biopsy. As reported by the authors, etanercept was prescribed with improvement of kidney function and arthralgias.Recently, Domingos et alA 61-year-old man presented to the emergency department for macroscopic hematuria and reduced urinary output. He had previous medical history of diabetes and AS diagnosed 2 years before. Usual medication consisted in glibenclamide, metformin, and infliximab, without recent use of NSAIDs. The patient denied asthenia, dyspnea, cough, hemoptysis, or other relevant complaints including upper respiratory symptoms. On examination, he was afebrile, hypertensive, and anuric with peripheral edema, but without need for supplemental oxygen therapy. He did not show any signs of rash or cutaneous purpura. Lab test revealed AKI with sCr of 6.4 mg/dL and urea of 130 mg/dL. Serum electrolytes, CRP, and albumin were within normal range. Thorax x-ray showed mild pleural effusion and renal ultrasound excluded obstruction. Diuretic therapy was initiated without improvement and the patient was started on hemodialysis. Complementary investigation revealed negative ANCA, anti-glomerular basement membrane, ANA, and anti-dsDNA antibodies. Screening for hepatitis B, C, and HIV were negative, as were other microbiologic studies. Serum electrophoresis was unremarkable. Kidney biopsy was performed and revealed a globally proliferative glomerulonephritis with extensive endocapillary and extracapillary proliferation, with total cellular crescents in 8 of the 15 glomeruli and necrotizing lesions in five of them . TubulesFinally, we describe a case of a 38 year-old man with end-stage CKD on peritoneal dialysis (PD). During PD follow-up, he presented with a constitutional syndrome characterized by progressive weight loss, low grade fever, inflammatory arthralgia, mainly of the lumbar joints but occasionally of the wrist and the elbow, polyserositis, and sustained elevated CPR. There were no complaints suggestive of infection including peritonitis, dialysis dose was adequate (Kt/V of 2), and the patient was euvolemic. Labs on admission were remarkable for normocytic normochromic anemia with hemoglobin of 7.4 g/dL, high ferritin levels (685 mg/dL), elevated ESR (87 mm/h), and CPR (140 mg/L). Extensive investigation for occult neoplasia and infectious diseases were all negative, as were ANA, anti-dsDNA, ANCA, and rheumatoid factor. Complement levels were normal.CKD had been diagnosed two years before after the patient presented with NS , impaired kidney function (sCr 1.7 mg/dL), and hematuria. The patient also had a previous history of lower back pain starting at young age, chronic NSAIDs use (resumed when CKD was diagnosed), overweight, hypertension, and active smoking.As an undiagnosed autoimmune disease was suspected, previous kidney biopsy was reviewed . Light m to 35%, depending on case series and mainly reflecting involvement by urinalysis alterations, although impaired kidney function has also been described. Renal pathology, on the other hand, is largely unknow. Previous reviews report AA amyloidosis, followed by IgAN, as the most common histological findings in kidney biopsies of AS patients. Since then, a small number of case series and some case reports have been published. Results are summarized in Manifestations of kidney disease in AS may not be as rare as initially thought. Reported prevalence varies from 8. In the present study, we highlight a case previously reported by Domingos et al. The patient presented with nephrotic syndrome and ERS >100 mm/h at the time of kidney biopsy and was successfully treated with etanercept. Lee et al showed similar results. Anti-Tumor Necrosis Factor (TNF)-α, together with NSAIDs, are currently the mainstay treatment for AS. We hypothesize that the reduced prevalence of AA amyloidosis in our series, compared with existing literature, may be due to a lower degree of inflammation in our patients and that further reduction of this diagnosis is expected in future cohorts due to novel and more efficient therapeutic regimens.Both AA amyloidosis and CIN were the most frequent diagnoses in our study. Regarding AA amyloidosis, evidence suggests that up to 6.1% of the AS patients may develop this complication following a 20-year period with a mean time from diagnosis of 14.4±10 years. High ESR has been reported as an independent predictive factor for renal AA amyloidosis. Furthermore, the association between the repeated use of NSAIDs and CIN is well established. Given its ubiquitous use in this particular disease, we hypothesize that even if we could not establish previous medications in some of the patients, the high prevalence of CIN in our series may be attributed to NSAIDs use . Nevertheless, we cannot completely exclude CIN as an uncommon renal manifestation of AS. More studies with larger cohorts are needed to investigate this possibility. Although we did not find a case of acute interstitial nephritis (AIN), there is one case report of adalimumab-associated AIN for treatment of AS. As other biological agents are being studied and increasingly used, we urge clinicians to be highly suspicious of this diagnosis as well.Although CIN is uncommon in other series, we do not find our results surprising. As previously discussed, NSAIDs are part of the first-line therapy for AS and are commonly used over a long period of time, being the only medication needed for many patients. However, we believe this association should be interpreted with caution. As IgAN is the most common glomerulonephritis worldwide, we cannot exclude that this association occurs by chance. Moreover, we should be aware that the largest series of biopsy-proven kidney disease in AS were conducted in Asian populations where IgAN is particularly common. In our series, IgAN was the third most frequent diagnosis. It has been suggested that downregulation of IgA Fc receptors (CD89) on blood phagocytes of AS patients leads to IgA immune-complex defective clearance and may explain more than a fortuitous association. Interestingly, in a recent French nationwide study, spondyloarthritis (SpA)-associated IgAN was shown to have poorer prognosis compared to primary IgAN. These patients seem to present with faster decline in kidney function and greater prevalence of crescents on pathological examination. The case described in the present study illustrates these results, where a crescentic IgAN was diagnosed in a Caucasian patient with AS. The reason of these findings is still unknown and deserves further investigation, although systemic inflammation mediated by TNF-α may play a role.AS has long been described as a cause of secondary IgA nephropathy, FSGS, and unspecified proliferative GN. Given their rarity, it is difficult to establish causality. In our study, patients diagnosed with FSGS had no other known factors suggestive of a secondary cause. The only case of MN was diagnosed in 1999, before the anti-PLA2R era, and thus we cannot exclude a coincidental diagnosis of a PLA2R-associated MN. We also highlight a case of IC-MPGN. To our knowledge, this is the first case described in the literature.Other less commonly described pathological alterations in AS patients include MNThe population analyzed in our cohort is somewhat different from the ones in previous series. Although we found a similar male predominance, we also showed that our patients were on average older at the time of kidney biopsy than previously reported. Considering that AS is commonly diagnosed in early adulthood, this may have impacted our results, as older age is probably associated with longer course of disease.. In contrast with their results, we found a higher prevalence of CIN and a lower prevalence of amyloidosis. Also, we found one case of IC-MPGN and one MN, pathological patterns not described in their series.Our study has several limitations. The retrospective design with a long period of inclusion and multicentric origin of the patients hindered collection of all relevant clinical data. Besides, given the small number of patients, it was not possible to establish significant correlations. Thus, we present an observational study describing renal pathological alterations in AS patients for a 36-year period and present illustrative cases. Despite the limitations, this study is remarkable for being one of the largest series addressing this issue in Caucasian patients, together with the one from Taarit et al, mainly in Asian cohorts. Moreover, it has been suggested that SpA-IgAN may be associated with poorer renal outcomes compared to primary IgAN in Caucasian patients. As renal abnormalities may contribute to long-term prognosis in a sizable portion of AS patients, larger prospective studies are needed to investigate kidney disease in AS.Renal manifestations of AS include a heterogenous group of diseases that are poorly characterized. They may be related to the autoimmune disease or to treatment modalities. In the past, AA amyloidosis was the most common diagnosis. More recently, a number of case series showed an increasing prevalence of IgAN


The optimal control thresholds for systolic blood pressure (SBP) and diastolic blood pressure (DBP) in patients with white matter hyperintensity (WMH) are still unclear.A longitudinal retrospective study of patients with brain magnetic resonance imaging (MRI) scans with intervals of more than 3  years was conducted. Blood pressure records during hospitalization and from outpatient visits between baseline and the last MRI scan were collected. The outcome was the change in total WMH from baseline to the final visit.n = 121), mild WMH group (n = 126), and moderate to severe WMH group (n = 210). Both baseline and longitudinal mean SBP, DBP, and SBP SD were significantly associated with WMH severity (p < 0.05). An average SBP of 130-140 mmHg  was associated with a higher risk of WMH progression. DBP ≥ 90 mmHg  was associated with a higher risk of WMH progression, but was not after adjusted for other covariates. Longitudinal BP variability was not significantly associated with WMH progression.Among the 965 patients with MRI scans, 457 patients with detailed longitudinal blood pressure records were ultimately included and classified into the WMH absent group (Both SBP and DBP had a stronger relationship with the severity of WMH. A target mean SBP of <130 mmHg and mean DBP of <80 mmHg was associated with a lower risk of WMH progression. An observational study revealed that a systolic blood pressure (SBP) higher than 160 mmHg or lower than 140 mmHg was associated with higher risk of WMH progression compared to an SBP between 140 and 160 mmHg in patients over 80 years old , indicatCurrently, whether diastolic blood pressure (DBP) plays an important role in the development and progression of WMH remains controversial . SeveralTo provide more evidence for SBP and DBP control in patients with WMH, this study mainly focused on longitudinal SBP and DBP data from baseline to the final MRI scan. Second, in this study, we aimed to determine the optimal threshold of mean SBP and DBP, and BP variability associated with a lower risk of WMH progression.2.2.1.This was a longitudinal retrospective study involving patients admitted to Dalian Central Municipal Hospital between January 1st, 2008, and January 1st, 2022, with dynamic MRI scans with intervals of more than 3 years and detailed blood pressure records between the baseline and last magnetic resonance imaging (MRI) both in hospitalization and outpatient visits. The inclusion criteria were as follows: (1) age over 18 years old; (2) BP records of more than 5 times every year. The exclusion criteria were as follows: (1) WMH with a defined or suspicious diagnosis of gene disease such as cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL); (2) WMH with a defined or suspicious diagnosis of acute inflammation or immune-mediated small vessel disease; (3) patients with large area cerebral infarction that influenced the analysis of WMH; and (4) patients without detailed clinical data.2.2.Baseline demographic variables, including age, sex, and education, were collected. Clinical variables, including history of hypertension, diabetes mellitus, hyperlipidemia, hyperhomocysteinemia, smoking, alcohol consumption, cardiovascular disease, atrial fibrillation, heart failure, kidney dysfunction, chronic respiratory disease, autoimmune disease, thyroid disease, anxiety, and depression, were all collected. The average interval of MRI from baseline to the last scans was calculated between groups. Etiology of hospitalization were also collected.2.3.BP values were collected from inpatient records , outpatient visit records, community monitoring records, and home monitoring records . BP values were calculated as baseline mean SBP and DBP values (mmHg), mean SBP and DBP values for longitudinal control (mmHg), and two commonly used BP variability indices, including SDs and coefficients of variation (CVs). The intervals of mean SBP were stratified into <130 mmHg, 130–140 mmHg, 140–150 mmHg, and ≥ 150 mmHg; the intervals of mean DBP were stratified into <80 mmHg, 80–90 mmHg, and ≥ 90 mmHg. BP variability were calculated using the SD (mmHg), and CV  . BP SD a2.4.All patients had undergone dynamic MRI scans . The presence and severity of WMH was assessed based on the baseline and last MRI by two neuroimaging specialists according to the semiquantitative Fazekas scale . If the 2.5.Baseline characteristics of the study population, categorized based on the severity of WMH, were compared with standard statistics. Continuous variables are expressed as the mean (SD) or median . Categorical variables are presented as counts (percentages). Fisher’s exact tests or chi-square tests were used for categorical variables. ANOVA or Kruskal–Wallis tests were used for continuous variables. Ordinal logistic analysis was used to evaluate the associations between different BP values and the severity of WMH. Binary logistic regression was used to analyze the association between different BP thresholds and the risk of WMH progression, of which Model 1 was not adjusted and Model 2 was adjusted for age, education level, diabetes mellitus, hyperhomocysteinemia, smoking status, stroke, kidney dysfunction, and etiology of hospitalization.p value <0.05 was considered significant. All statistical analyses were performed using SAS version 9.4 .A two-sided 3.3.1.n = 121), mild WMH group (n = 126), and moderate to severe WMH group (n = 210) (p < 0.001). Other risk factors with significant differences between groups were education level, hypertension, diabetes mellitus, hyperhomocysteinemia, smoking status, history of stroke, kidney dysfunction. The mean intervals of MRI from baseline to the last scan were 6.52 ± 2.97 years in total, 6.83 ± 2.90 years in the WMH absent group, 6.47 ± 2.83 years in the mild WMH group, and 6.38 ± 3.09 years in the moderate to severe WMH group (p = 0.24). Etiology of hospitalization were also different between groups, especially hospitalization due to cerebral vascular disease (p < 0.001). The median number of BP measurement time points was 16  . Demogras was 16 .3.2.p < 0.001, p < 0.001, The mean baseline SBP was 129.25 ± 10.52 mmHg in the WMH absent group, 131.33 ± 11.32 mmHg in the mild WMH group, and 141.03 ± 13.72 mmHg in the moderate to severe WMH group , and patients with a history of stroke , but not in patients with age over than 70 years or without a history of stroke , p = 0.01], male patients , and patients with a history of stroke  but not in patients aged over 70  years, diabetic patients, female patients, or patients without a history of stroke , f stroke . A longif stroke .4.In this retrospective study, both SBP and DBP values were strongly associated with the severity of WMH. A mean SBP value lower than 130 mmHg, a mean DBP value lower than 80 mmHg were associated with a lower risk of WMH progression, but only mean SBP was significant after adjusted for age, education level, diabetes mellitus, hyperhomocysteinemia, smoking status, stroke, kidney dysfunction, and etiology of hospitalization. Although longitudinal SBP variability and DBP variability were associated with the severity of WMH, but were not related to risk of WMH progression.In the SPRINT study , intensiUntil now, the association between DBP and WMH has remained controversial. Two studies using the data from the Northern Manhattan study revealed a significant association between DBP and WMH progression  and the In our study, SBP SD, SBP CV, DBP SD, and DBP CV was not associated with the risk of WMH progression. Although SBP SD >11.1 mmHg and an SBP CV of >12.24% was associated with the risk WMH progression, but this was not significant after adjusting for age, education level, diabetes mellitus, hyperhomocysteinemia, smoking status, stroke, kidney dysfunction, and the etiology for hospitalization. Previous studies had reported an independent association between 24 h BP variability and WMH volumes/severity . There wSubgroup analysis in our study revealed that the risk of WMH progression was significantly reduced when the SBP value was lower than 130 mmHg and the DBP value was lower than 80 mmHg in patients younger than 70 years old and patients with a history of stroke. This was consistent with a previous meta-analysis that indicated a higher risk of WMH progression in patients under 70 years old than in patients over 70 years old when their DBP increased . A cliniPatients with hypertension tend to develop lower myelin content, have more severe brain microstructure impairment , have a This study had several differences and limitations compared with other studies. The first was that we used the Fazekas scale to semi-quantitatively analyze severity and WMH progression rather than WMH volume. As the Fazekas scale is a commonly used tool both in the clinic and in clinical studies, it may be easier and applicable to help clinicians understand the severity of WMH and the velocity of WMH progression. The second was that we did not analyze a lower SBP of <120 mmHg or < 110 mmHg and DBP <60 mmHg as there were very few patients with a mean SBP of lower than 120 mmHg and DBP lower than 70 mmHg in our study. The third limitation of the retrospective study was that the total number of blood pressure records and the time interval between blood pressure measurements, which might differ among different patients as the number of hospitalizations and outpatient visits were different. These blood pressure records may not be adequate to represent the patients’ average daily control of blood pressure.5.In this longitudinal retrospective study, both SBP and DBP had a strong relationship with the severity of WMH. A target mean SBP lower than 130 mmHg and a mean DBP lower than 80 mmHg were associated with a lower risk of WMH progression. An SBP SD value <11.1 mmHg and an SBP CV value <12.24% were associated with lower risk of WMH progression, but DBP variability was not.The original contributions presented in the study are included in the article/All procedures were performed in accordance with relevant named guidelines and regulations and were approved by the ethics committee of the Dalian Central Municipal Hospital. Written informed consent was not required to participate in this study in accordance with the local legislation and institutional requirements.SL: Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Project administration, Resources, Software, Writing – original draft. MW: Data curation, Formal analysis, Supervision, Validation, Visualization, Writing – original draft. DG: Data curation, Investigation, Validation, Writing – original draft. YL: Data curation, Investigation, Validation, Writing – original draft. XZ: Data curation, Investigation, Validation, Writing – original draft. HL: Data curation, Investigation, Validation, Writing – original draft. CJ: Investigation, Validation, Writing – original draft. XN: Investigation, Conceptualization, Data curation, Formal analysis, Funding acquisition, Methodology, Project administration, Resources, Writing – review & editing. JL: Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Project administration, Writing – review & editing.


Background2. Prior studies have reported the existence of a correlation between tourniquet deflation and an increase in intracranial pressure in patients undergoing surgery under general anesthesia. However, there is a dearth of literature demonstrating such relationships among patients undergoing surgery under subarachnoid block in the Indian setting. The present research was conducted to study the variations in intracranial pressure after the deflation of the tourniquet by measuring the optic nerve sheath diameter (ONSD) using ultrasound among patients undergoing orthopedic surgery of the lower limb under spinal anesthesia at a tertiary care hospital in eastern India.Orthopedic surgeries of the lower extremities frequently require exsanguination and the use of pneumatic tourniquets. However, the deflation of the tourniquet is accompanied by predominant metabolic changes such as an increase in PaCOMethodology2, EtCO2, and ONSD were noted 15 minutes before administration of subarachnoid block (T0), just before tourniquet deflation (T1) and at 5, 10, and 15 minutes after tourniquet deflation .After obtaining clearance from the Institutional Ethics Committee, this prospective observational study was conducted among 45 patients undergoing orthopedic surgeries of the lower limb using a pneumatic tourniquet. Changes in intracranial pressure following tourniquet deflation were recorded by measuring ONSD by ultrasound in these patients. Heart rate (HR), mean arterial pressure (MAP), SpOResults2 showed a significant increase compared to baseline values at every point of observation intraoperatively whereas MAP showed a significant decrease (p < 0.05). For all parameters , the most significant change in observation was noted at T10, i.e., 10 minutes after the deflation of the tourniquet.The ONSD varied significantly at each point of observation (p < 0.05). The ONSDs at 5 and 10 minutes after the deflation of the tourniquet were significantly greater than that at T0 (p = 0.002). EtCO Conclusions2. However, the results obtained cannot be validated outside the present research owing to the observational nature of the study and limited sample size. Thus, it is difficult to arrive at a definitive conclusion. Further large-scale multicentric studies may be needed to substantiate the findings of this study.The significant finding in this study was that the ONSD measurements recorded by ultrasound were increased after the deflation of the tourniquet and that this change can be attributed to an increase in EtCO Throughout the world, tourniquets are routinely and safely used during limb surgeries . Due to However, using a tourniquet can lead to several complications, both local and systemic. These concerns include mechanical compression of the underlying structures, ischemia, and reperfusion effects . High cu2) from the released ischemic metabolic products during the reperfusion period causes increased PaCO2, which simultaneously causes cerebral vasodilatation and an increase in cerebral blood flow (CBF), ultimately leading to an increase in ICP [When the tourniquet is deflated, the increase in carbon dioxide , Tata Main Hospital . A total of 45 patients aged between 18 and 65 years, belonging to the American Society of Anesthesiologists (ASA) Physical Status Classification System grade I-II, and scheduled to undergo elective orthopedic surgery on a lower extremity using a tourniquet under spinal anesthesia were included in this study. Patients aged 65 years or more; those who required bilateral tourniquet usage; those with a history of orbital trauma, optic nerve pathology, glaucoma, asthma, or coronary obstructive pulmonary disease; those with a previous corneal or intraocular surgery; patients with increased ICP, coagulopathy, and local site infection; and those refusing to participate in the study were excluded. Further, patients in whom conversion to general anesthesia was required for any reason perioperatively were also excluded from the study.2, and EtCO2. This was followed by performing neuraxial block  using a 3 mL dose of 0.5% bupivacaine at the level of L3-L4 or L4-L5, as suitable, and simultaneously co-loading with 1 L of Ringer’s lactate solution. In all patients, a standard pneumatic tourniquet with an 11-cm-wide cuff was placed with the distal edge 15 cm proximal to the proximal pole of the patella, and it was inflated to an inflation pressure of a pneumatic tourniquet pressure which is equal to systolic blood pressure (SBP) + 100 mmHg.All patients underwent standard ASA monitoring including electrocardiogram (ECG), noninvasive blood pressure (NIBP), SpO2, EtCO2, and ONSD values were recorded 15 minutes before the administration of subarachnoid block (T0), just before the deflation of the tourniquet (T1) and at 5, 10, and 15 minutes after the deflation of the tourniquet . Age, sex, body mass index (BMI), ASA score, and duration of tourniquet use were also noted for each patient. All details were recorded in a predesigned, pretested case record form.Sonographic measurement of ONSD  for all patients was performed by a single anesthesiologist with an experience of at least more than 25 ultrasound measurements. A thin gel layer was applied to the upper eyelid with the patient in the supine position and with the eyes closed  and statistical analysis was done using SPSS version 16.0 . The data were analyzed by appropriate statistical tools and represented as tables, graphs, diagrams, etc. Continuous variables were expressed as mean ± standard deviation (SD), and categorical variables were expressed as relative frequency and percentage.2 with different time points were assessed using the Friedman test. Pairwise significant changes in ONSD and EtCO2 at different time points  were assessed using the Wilcoxon signed-rank test. Correlation between ONSD at different time points and EtCO2 at different time points was assessed using Spearman’s correlation test. All tests were two-sided. A p-value <0.05 was considered statistically significant.Significant changes in ONSD, HR, SBP, DBP, MAP, and EtCOThe final analysis was done on 45 study participants. The mean age of the study participants was 39.7 ± 11.2 years with a male-to-female ratio of 2.75:1. More than half of the study participants did have any associated comorbidity (57.8%). The proportion of subjects having diabetes only, hypertension only, and both diabetes and hypertension were 4.4%, 31.1%, and 6.7% respectively. The majority of the subjects belonged to the ASA grade I Physical Status classification (73.3%), and the mean body weight was 68.31 ± 7.06 kg. Spinal anesthesia was introduced at the intervertebral level of L3-L4 for 15.6% of the patients and at the level of L4-L5 for the remaining 84.4% of the patients. The mean dose of anesthesia used was 3.02 ±0.19 mL. The mean tourniquet pressure at the time of surgery was 309.33 ± 17.89 mmHg, and the mean duration of tourniquet application was 98 ± 12.0 minutes.2 were significantly different at each point of measurement (p < 0.05), as shown in Table The temporal changes in ONSD, HR, SBP, DBP, MAP, and EtCO2 at baseline T0 (just before induction) and at other points of observation  showed significant variations in ONSD at each point of observation (p < 0.05). The ONSD at T5 and T10 were significantly greater than that at T0 (p = 0.002), as shown in Table Pairwise analysis between the measurement of ONSD and EtCO2 analyzed at different points of observation intraoperatively showed that although there was a weak negative correlation observed between ONSD and EtCO2 at T0, T1, T5, and T15, none of the associations were statistically significant (p > 0.05). The best correlation between ONSD and EtCO2 was noted at T10 .Correlation between differences in ONSD and EtCO2), arterial carbon dioxide partial pressure (PaCO2), potassium ion, and lactate levels fluctuate because of tourniquet inflation and deflation [2) into the systemic circulation that has collected during the ischemia phase. A rise in ICP follows the resulting elevation in PaCO2. Although most healthy patients can compensate for and tolerate this increase in CBF, it may result in an increase in ICP in patients with impaired intracranial compliance [The use of pneumatic tourniquets in orthopedic surgery provides the benefits of reduced operating time and lesser blood loss during the procedure. The pH, arterial oxygen partial pressure , immediately before tourniquet deflation (T1), and at 5, 10, and 15 minutes after tourniquet deflation . The temporal changes in ONSD, HR, SBP, DBP, MAP, and EtCO2 were significantly different at each point of measurement (p < 0.05). The ONSD showed significant differences at each point (p < 0.05). The ONSDs at T5 and T10 were significantly greater than that at T0 (p = 0.002). This study finding is consistent with that reported by Kim et al. [The present study was conducted to investigate the variations in ICP following tourniquet deflation by measuring ONSD by ultrasound. HR, MAP, ETCOm et al.  where th2 significantly increased compared to baseline values at every point of observation intraoperatively (p < 0.05). For all parameters , the highest change in observation was noted at T10, i.e., 10 minutes after the deflation of the tourniquet. The best correlation between ONSD and EtCO2 was noted at T10 with a correlation coefficient of r = 0.15, p = 0.033. This finding is similar to that reported by the aforementioned studies, where the change in ONSD was significantly correlated with the change in the EtCO2 after tourniquet deflation [Results from our study showed a significant decrease in MAP whereas EtCOeflation ,15. HoweIn many investigations, intracranial hypertension was defined as an ICP value of more than 20 mmHg . The ONSThis study did have some limitations. First, the measurement of ICP by invasive methods, such as the placement of an intraventricular catheter, is considered the gold standard. This was not done in this study due to the requirement of invasive surgical techniques and ethical considerations. Second, this research was performed as an observational study only, and further prospective randomized trials in this domain may be required. Lastly, because the study was conducted in a single hospital, it has the disadvantages of a limited sample size and centripetal bias. Further studies in different settings in other parts of the country and on a larger population are necessary to validate our study findings.2. However, these findings cannot be validated outside the present research owing to the observational nature of the study and limited sample size. Thus, it is difficult to arrive at a definitive conclusion. Further large-scale, multicentric studies may be needed to substantiate the findings of this study.The present study is the only study, to our best knowledge, conducted in the Indian setting to evaluate changes in ICP following tourniquet deflation after orthopedic surgeries of the lower limb under subarachnoid block. The significant finding in this study was that the ONSD measurements obtained by ultrasound were increased following tourniquet deflation and that this change was linked to an increase in EtCO


Background: Chronic kidney disease (CKD) has various etiologies, making it impossible to fully understand its complex pathophysiology. Elevated levels of plasma creatinine, proteinuria, and albuminuria and declined eGFR are traits observed in CKD patients. The current study attempts to highlight the collagen triple helix repeat containing 1 (CTHRC1) protein as a putative blood biomarker for CKD in addition to existing recognized indicators of CKD progression. Methods: A total of 26 CKD patients and 18 healthy controls were enrolled in this study. Clinical characteristics and complete blood and biochemical analyses were collected, and human ELISA kits were used to detect possible CKD biomarkers. Results: The study’s findings showed that CTHRC1 correlates with key clinical markers of kidney function such as 24 h urine total protein, creatinine, urea, and uric acid. In addition, CTHRC1 demonstrated a strong significant difference (p ≤ 0.0001) between the CKD and control group. Conclusions: Our research demonstrates that the plasma level of CTHRC1 can distinguish between those with CKD and healthy patients. Plasma CTHRC1 levels may aid in the diagnosis of CKD given the current state of knowledge, and these results call for further investigation in a wider, more diverse patient group. Chronic kidney disease (CKD) has a varied etiology, and comprehending its complicated pathophysiology is inherently difficult . EndotheThe main causes of renal fibrosis are considered to be prolonged inflammation, excessive accumulation of ECM components, and initial renal injury, overall leading to renal scar formation and end-stage renal disease (ESRD) ,5. It isThe involvement of the both canonical and non-canonical TGFβ/Smad signaling pathways in renal fibrosis has been thoroughly investigated. Edeling et al. showed that TGFβ/Smad interacts with other signaling pathways, such as Wnt/β-catenin, Jagged1/Notch, and Hedgehog, during epithelial differentiation, myofibroblast transformation, and proliferation . Collagen triple helix repeat containing 1 (CTHRC1) is a secreted, glycosylated protein that is normally expressed in mesenchymal connective tissue during embryonic development. The overexpression of CTHRC1 in adult mesenchyme-derived cells is associated with enhanced cell motility and the invasiveness of cancer metastases . It has Numerous studies demonstrate that the Wnt/β-catenin signaling pathway is crucial for the progression of renal fibrosis, podocyte injury, and proteinuria ,12,13,14According to a report, CTHRC1 stabilizes the formation of the WNT5A-ROR2 complex, allowing it to specifically activate the planar cell polarity pathway of Wnt signaling . CTHRC1 p > 0.05 in Kaplan–Meier plotter) when their CTHRC1 transcriptional level was greater in various cancers.Studies have shown that CTHRC1 alters cell adhesion via modulating the production of molecules, including integrin and MMPs, allowing cells to move more freely and increasing tumor spread and invasion. Moreover, it was shown that CTHRC1 has a huge impact on the formation of fibrosis in the liver  via the Taking into account the crucial roles of TGFβ signaling, as well as canonical and non-canonical pathways in CKD, we hypothesized that CTHRC1 can have a certain role in renal dysfunction. To address this question, a randomized cross-sectional pilot study was performed. In this study, we aimed to analyze the levels of CTHRC1 in the peripheral blood of CKD patients and to test CTHRC1′s association with other markers of CKD. This project is a prospective observational validation study. The 26 patients with established diagnoses of CKD were recruited from the “National Scientific Medical Center” hospital while they were admitted to the internal medicine department. Eighteen volunteers were enrolled from the outpatient clinics. All of the included participants had stable clinical circumstances and no active malignancy, autoimmune, cardiovascular, neuropsychiatric, or inflammatory illnesses. Samples were collected to the hospital in a time period of 14 months. The approximate time interval averaged 2–3 patients per month. Up until the conclusion of the study, the laboratory researchers were blinded to data revealing patients’ clinical outcomes. Independent blood and urine samples were taken without taking the patients’ prognosis into account. For each participant, blood metabolic profiles were acquired, including those for serum creatinine, serum urea, glucose, uric acid, total protein, AST, ALT, lipid profiles, and protein fractions. A 24 h urinalysis with values for the urine protein, sodium, potassium, uric acid, and creatinine was also defined at the time of registration.The following inclusion criteria for CKD patient group were used: according to KDIGO classification, CKD stages varied between 1 and 3; enrolled patients’ age was between 18 and 65 years old; and proteinuria levels were greater than 300 mg/24 h. 2, n = 13), CKD stage 2 , and CKD stage 3 . The control group consisted of 18 subjects; 34.7 ± 8.05 years of age; without a medical history of renal disease, and with eGFR more than 60 mL/min/1.73 m2.CKD patients with the following characteristics were excluded: glomerular filtration rate (GFR) < 15 mL/min; females at any stage of pregnancy; patients with accompanying diseases such as diabetes mellitus (Type I and II), any type of cancer, infectious diseases, and any other inflammatory and autoimmune diseases specifically liver fibrosis, rheumatoid arthritis, and other life-treating comorbidities/conditions. The diagnosis of CKD was based on the levels of proteinuria and was not confirmed by kidney biopsy. CKD-EPI Creatinine Equation (2021) was used to estimate GFR and CKD stages, as recommended by the National Kidney Foundation . CKD patAll work within the project was conducted in accordance with international and national legal and ethical principles. All study procedures were approved by the Nazarbayev University Institutional Review Ethics Committee on 25 February 2020 (NU-IREC 208/06122019). Written informed consent was obtained from all participants. Peripheral venous blood samples were collected from each participant in the morning on an empty stomach. Each participant was identified before to sampling and given all the information required to be entered into the laboratory information system. The puncture was performed while the participants were seated; to prevent venous stasis, the puncture site was cleansed with 70% alcohol, and the tourniquet was applied for less than three minutes. To ensure the traceability between the patient and the samples, each tube was assigned a distinct bar code. Blood samples were collected on etheylenediaminetetraacetic acid (EDTA) tubes for complete blood count (CBC), and lithium heparin tubes for biochemical analysis. EDTA plasma was separated within 30 to 90 min of sample collection; samples were centrifuged at RT for 15 min. at 2200 g. After the CBC analysis, plasma were stored at −40 °C until the CTHRC1 ELISA test was performed.All laboratory measurements were performed in the laboratory at the “National Scientific Medical Center” hospital. Plasma creatinine, urea, and CRP concentrations were measured using an automated biochemical analyzer (Cobas 6000) with the commercially available kits. CBC analysis was completed using a Sysmex-XN 3000 analyzer. CTHRC1 levels were measured in the Biology department at the PI “National Laboratory Astana”, Nazarbayev University using Human CTHRC1 SimpleStep ELISA kit , according to the manufacturers’ protocol. Human CTHRC1 SimpleStep ELISA kit , TNF alpha ELISA Kit , Human MMP9 Elisa kit , and Human MMP2 Elisa kit  were used to detect proteins in plasma samples. First, stock standards were prepared according to the Human CTHRC1 SimpleStep ELISA kit protocol. The 96-well plate strips included with the kit were supplied and ready to use. All materials and reagents were equilibrated and prepared at RT prior to use. Sample and standards were diluted to ½ for CTHRC1, ½ for TNF alpha, 1/10 for MMP2, and 1/50 for MMP9 with a Sample Diluent buffer. Fifty microliters of each standard and sample was added into appropriate wells. Then, 50 µL of the Antibody Cocktail was added to each well. The plate was sealed and incubated for 1 h at RT on a plate shaker set to 400 rpm. Each well was washed with 3 × 350 µL 1× Wash Buffer PT. The wells were washed by aspirating and then dispensing 350 µL 1× Wash Buffer PT into each well. Next, 100 µL of TMB Development Solution (provided with the kit) was added to each well and incubated for 10 min in the dark on a plate shaker set to 400 rpm. The reaction was stopped by adding 100 µL of Stop Solution to each well. The absorbance of each plate was measured at 450 nm with the reference wavelength of 620 nm using the VarioScan Flash microplate reader  . t-test was used to compare normally distributed data; otherwise, the Mann–Whitney U-test was used. For qualitative variables, the Pearson’s correlation test was used. The link between two continuous variables was described by non-parametric Spearman correlation coefficients. When employed as continuous variables, CTHRC1 levels had a skewed distribution and underwent log transformation. All reported p-values were two-tailed, and significance was set at p value ≤ 0.05. For statistical analysis and visual representations, GraphPad Prism version 8.0.1 for Windows was used .The median and interquartile ranges (IQR) or the mean with standard deviation (SD) were used to summarize patient data. Student’s p value = 0.0279) (p = 0.0059), among which the difference in neutrophils (p = 0.0089) and monocytes (p = 0.0068) between the CKD and control groups was significant (p < 0.0001).The analysis of a 24 h urine collection is the gold standard for quantifying proteinuria. Expectedly, the median protein levels in 24 h urine collection for the CKD and control groups were 1.66 g/24 h and 0.09 g/24 h, respectively . The mea 0.0279) . The meanificant . Lipid lnificant . ELISA tp = 0.0005) (p = 0.0025) (p = 0.0026) (p = 0.0068) (p = 0.0366) (p = 0.0156)  A, uric a 0.0025) B, urea ( 0.0026) D, total  0.0068) E and eGF 0.0366) H. CTHRC1 0.0156) F were anp ≤ 0.05) and eGFR (p ≤ 0.05) values demonstrated adequate significant difference (p ≤ 0.0001) (p ≤ 0.01)   between  ≤ 0.01)  were als ≤ 0.01) .p = 0.9685) (p = 0.9661) (p = 0.2522) (p = 0.2522) (p = 0.0038)  A, neutro 0.9661) B, basoph 0.2522) D, and eo 0.2522) E in the  0.0038) C. In add 0.0038) H–J.2 (eGFR < 60) and above 60 mL/min/1.73 m2 (eGFR > 60)  , where C2 (eGFR < 60) was 0.7619 (0.5923 to 0.9315)  , whereasThe measurement of blood creatinine concentrations and subsequent determination of the GFR are the foundations of contemporary CKD diagnosis and course monitoring . This meAlthough there are many evidences showing an association of WBC and other inflammatory markers with kidney function ,33, therp = 0.0366)  and elevated in 20% of individuals with red hair and fair skin. The median concentration of CTHRC1 for healthy volunteers was 69.6 ng/mL . This va 0.0366) H. It is TGFb regulates the expression of CTHRC1 in many signaling pathways, including TGF-β, Wnt, integrin β/FAK, PI3K/AKT/ERK, and PKC-δ/ERK signaling pathways ,42.There are many studies showing the relationship between the TGFb family and CTHRC1, such as the induction of CTHRC1 transcription and expression by TGFb and BMP in NIH3T3 cells . During CTHRC1 inhibits collagen deposition and promotes cell migration by preventing Smad2/3 phosphorylation in TGF-β signaling . CTHRC1 To our knowledge, CTHRC1 was studied in CKD patients for the first time, and there is a lack of information regarding the role of this protein in CKD pathogenesis. Further studies would be required to elucidate the exact function in glomerular filtration and reabsorption. Based on the studies showing the significant role of Wnt/B catenin pathways, including ligands and receptors in CKD progression, we hypothesize that CTHRC1 should have an essential role as well.Numerous restrictions apply to our study, particularly, the limited sample size in each group, and due to its cross-sectional form, it is challenging to pinpoint the connection between CTHRC1 and the early-stage of CKD as well as the progression of the disease. To determine CTHRC1 expression in relation to disease stage, a large number of patients with stages from 1 to 5 should be included, and a longitudinal study would be necessary. Medical history, including the etiology of CKD and any current medications, was not reported in the current study.To further the obtained results, the effect of CTHRC1 to podocyte detachment and on fibroblast transformation to myofibroblasts as well as exact role of this protein in scar formation should be studied. This study is the second study in the Kazakhstani population where CTHRC1 is investigated; therefore, the threshold for CTHRC1 should be established for the Kazakhstani population.The study’s findings have shown that declines in kidney function are linked to an elevation of CTHRC1 levels in CKD patients. At the current level of understanding, elevated plasma CTHRC1 levels may indicate disease status in CKD, and these findings warrant confirmation in a larger, more comprehensive patient population. Our study demonstrated that CTHRC1 has a significant correlation with creatinine, total protein, urea, and uric acid, which are considered to be the main indicators of CKD and its progression. Therefore, we identify CTHRC1 as a potential marker of CKD, which can improve the diagnosis.


An increased blood pressure is a known comorbidity of both type 1 diabetes (T1DM) and obesity in children. Increasing evidence suggests a subtle interplay between epidermal growth factor (EGF) and renin along the juxtaglomerular system, regulating the impact of blood pressure on kidney health and the cardiovascular system. In this study, we investigated the relation between urinary EGF, serum renin and blood pressure in children with obesity or T1DM. 147 non-obese children with T1DM and 126 children with obesity, were included. Blood pressure was measured and mean arterial pressure (MAP) and the pulse pressure (PP) were calculated. Serum renin and urinary EGF levels were determined with a commercial ELISA kit. Partial Spearman rank correlation coefficients and multiple linear regression models were used to study the association between renin, the urinary EGF/urinary creatinine ratio and blood pressure parameters. The urinary EGF/urinary creatinine ratio is correlated with the SBP and the MAP in boys with obesity as well as in boys with T1DM. Multiple regression analysis showed that sex and pulse pressure in male subjects were found to be independently associated with renin. Sex, the presence of diabetes, age, the glomerular filtration rate and both pulse pressure and mean arterial pressure in male subjects were independently associated with urinary EGF/urinary creatinine. In conclusion, in boys with either obesity or diabetes, pulse pressure and mean arterial pressure are negatively associated with the functional integrity of the nephron, which is reflected by a decreased expression of urinary EGF. The burden of childhood obesity is undisputable. According to the World Health Organization, 340 million children and adolescents worldwide were overweight or obese in 2016 [In parallel with the obesity epidemic, also the incidence of Type 1 diabetes mellitus (T1DM) is increasing in youth . T1DM isIndependent of any associated comorbidities, hypertension is a major risk factor for deterioration of the kidney and cardiovascular function in adults . BesidesAlready in an early phase, tubulo-interstitial changes induced by glomerulopathies lead to diminished production and urinary excretion of epidermal growth factor (EGF), making urinary EGF a sensitive and ‘early stage’ biomarker for the deterioration of kidney function . In chilEpidermal growth factor (EGF) stimulates cell growth, proliferation and differentiation by binding to its receptor EGFR . In the In this study, we hypothesized that intrarenal renin production plays a role in the fluctuation of urinary EGF excretion, including a suppression of kidney EGF production by high intrarenal renin and vice versa. An increased blood pressure is a known comorbidity in children and adolescents with both T1DM and obesity, however the pathophysiological mechanisms differ between the conditions. In obesity, hypertension is (at least partly) caused by salt-retention and associated with a low to normal renin production  which inWere included at the Antwerp University Hospital (n = 147) between October 2016 and April 2018 in an observational, monocentric, prospective cohort study. Serum and urine samples were collected from each patient.Inclusion criteria: 8–18 years of age; T1DM diagnosis for at least one year; and insulin treatment of ≥0.5E/kg/d (thereby excluding patients with a significant autonomous insulin production).Exclusion criteria: obesity defined by a body mass index (BMI) z-score > 2, use diuretics, calcineurin inhibitors, platinum derivates or aminoglycosides and known genetic syndromes.Were recruited by consecutive inclusion at the paediatric obesity clinic of the Antwerp University Hospital through two research projects  (n = 126) . PatientInclusion criteria: Children with overweight or obesity (aged 8–18 years old) who were diagnosed with insulin resistance. Insulin resistance was defined by meeting one of the following three criteria, depending on a 3-hour oral glucose tolerance test (OGTT): a fasting insulin > 100 pmol/l; or a peak insulin during OGTT > 1000 pmol/l or a glycaemia that exceeds 140 mg/dl at 120’. The OGTT was performed after a 12-hour overnight fast and blood samples were withdrawn at six different moments: 0’, 15’, 30’, 60’, 120’ and 180’. Glucose levels > 140 mg/dl at minute 120 of the OGTT is an indicator of impaired glucose tolerance and therefore of insulin resistance , 26.Exclusion criteria: an underlying illness with intestinal malabsorption, an endogenous cause of obesity , epilepsy, use diuretics, calcineurin inhibitors, platinum derivates or aminoglycosides, T1DM and known genetic syndromes.In order to avoid overlap between the 2 populations, we explicitly excluded patients with T1DM with a BMI z-score > 2 as well as patients with obesity with characteristics of T1DM.The study was conducted in accordance with the Declaration of Helsinki and the principles of Good Clinical Practice. The study protocol was reviewed and approved by the Ethics Committee of the Antwerp University Hospital , 17/10/112 (WELCOME), 19/45/519 (ULTROMEC)). All patients and the parents or legal guardians of the children below 18 years old gave a written informed consent.Age, sex, medical and medication history, and laboratory values were extracted out of the electronic patient files for all patients.Height (cm) was measured to 0.1cm using a standing stadiometer and weight was measured to the nearest 0.05kg using a digital weighing scale.2. Weight, height and BMI were further analysed as z-scores using the Flemish Growth Study as reference population [BMI was calculated as weight in kg over height in mpulation . Overweipulation .The arterial blood pressure was measured three times consecutively by an automated validated oscillometric device at the right upper arm with an adjusted cuff. The mean value of these measurements was calculated. Systolic and diastolic blood pressure z-scores for age, height and sex were calculated .Pulse pressure (PP), a measure for artery stiffness and flow pulsatility , (PP) waMean arterial pressure (MAP) was calculated as DBP plus 1/3(PP), and is determined by small resistance artery function and cardiac output .Serum and urine creatinine were analysed with an automated Dimension Vista 1500 system .The estimated glomerular filtration rate (eGFR) was then calculated using the Bedside Swartz equation, which includes serum creatinine and height and is the preferred method in subjects under 18 years old .Urine EGF was measured using an EGF human Elisa kit® , according to the manufacturer’s guidelines. The detection limit of the assay was 3.9 pg/ml. Urine EGF was corrected for kidney function (creatinine) as previously published .Serum renin was measured using a Human Renin Quantikine ELISA kit® , according to the manufacturer’s guidelines . The detNormality was tested with Shapiro-Wilk test and visual inspection of QQ-plots. Since not all parameters were normally distributed, patient characteristics were presented per group (obesity/diabetes) as median with range (min-max). As it is known that serum renin levels are higher in boys when compared to age-matched girls , all datThe association between renine, the urinary EGF (uEGF)/urinary creatinine (uCreat) ratio and blood parameters was studied in each of the four subgroups (diabetes/obesity by sex) by partial Spearman rank correlation coefficients (rho), controlling for age and height-z-score. Both age and height-z-score were used as controlling variables as children with obesity were seen to be taller than non-obese peers.Finally, a multiple linear regression model was constructed for renin and log-transformed uEGF/uCreat ratio, containing sex, disease (obesity/diabetes), age, height-z-score, eGFR, PP, MAP and interactions between PP and sex, and between MAP and sex as explanatory variables. In this way a different association was allowed between blood pressure parameters and renin or uEGF/uCreat ratio for boys and girls. Adding an interaction between PP and disease or between MAP and disease did not significantly improve the model fit. Model assumptions were judged by looking at residual plots. Added variable plots were constructed to visualize the relation between renin or uEGF/uCreat ratio and blood pressure parameters after controlling for the remaining variables in the model.All analyses were performed in R 4.1.3 (R Core Team 2022) and significance was concluded when p-values were below 0.05.As presented in Based on the height z-scores, we see that children and adolescents with obesity were taller than their peers and had an increased BMI z-score meeting the criteria for obesity as described by the IOTF. The z-scores for height and BMI in children and adolescents with T1DM were within normal range.Both in boys with T1DM and boys with obesity, the serum renin levels are higher when compared to girls.th centile and 2.2% (3/139) displayed a DBP of more than 5 mmHg above 95th centile . In the subgroup with obesity, 7.3% (9/124) of the children and adolescents were in the pre-hypertensive range for SBP and 8.1% (10/124) for DBP. The criteria for stage 2 hypertension (> 5 mmHg above P99 for age and height) were only met in 2.2% of the T1DM group (0.7% DBP (1/139) and 1.4% SBP (2/139)), and in 4.0% of the population with obesity (2.4% DBP (3/124) and 2.4% SBP (3/124)). The boxplots shown in Pulse pressure was significantly higher in the T1DM group compared to the group with obesity (p < 0.001) after correction for age, sex and height-z-score, while no significant difference in MAP could be withheld. Overall, no significant difference in SBP z-score or DBP z-score was seen between the subpopulations with obesity or diabetes. Five percent (7/139) of the children and adolescents with diabetes had a SBP of more than 5 mmHg above 95In children and adolescents with T1DM, proteinuria was 14.5 (10.0–20.8) mg/dl and in children and adolescents with obesity 12.6 (8.2–18.0) mg/dl (p = 0.016). In children and adolescents with T1DM, microalbuminuria was 8.4 (5.6–12.6) mg/g creatinine and in children and adolescents with obesity 5.5 (2.9–7.8) mg/g creatinine (p<0.001). Eight percent of the children and adolescents with obesity and 10% of the children and adolescents with T1DM had microalbuminuria >30mg/g creatinine (p = 0.630).Partial correlations controlling for age and height z-score between renin, urinary EGF/ urinary creatinine ratio, blood pressure parameters and eGFR are depicted in Two multiple linear regressions models were fitted to determine which parameters are independently related to renin or urinary EGF/urinary creatinine as presented in Aiming at dissecting a hypothetical interaction between systemic blood pressure, plasma renin and urinary EGF in children, we compared the characteristics of these three actors in two distinct paediatric populations, namely children with obesity and T1DM, thereby avoiding any overlap of disease. Although no direct link between renin and urinary EGF could be withheld, two interesting patterns of association were observed in male subjects: pulse pressure was found to be independently related to renin, and both pulse pressure and mean arterial pressure showed a clear association with urinary EGF.th centile and 2.2% (3/139) displayed a DBP of more than 5 mmHg above 95th centile . In the subgroup with obesity, 7.3% (9/124) of the children were in the pre-hypertensive range for SBP and 8.1% (10/124) for DBP. The criteria for stage 2 hypertension (> 5 mmHg above P99 for age and height) were only met in 2.2% of the T1DM group (0.7% DBP (1/139) and 1.4% SBP (2/139)), and in 4.0% of the population with obesity (2.4% DBP (3/124) and 2.4% SBP (3/124)).Vascular health is determined by arterial vascular stiffness, which in turn comprises both large artery elasticity (non-invasively measured by pulse pressure (PP)) and small artery compliance ) . SystemiChildren with obesity had lower renin levels compared to the paediatric T1DM group although this difference was only significant in the male subjects. The lower renin levels observed in the subjects with obesity correspond to the well-documented difference in pathophysiological cause of hypertension between obese and diabetic subjects, namely salt-driven low or normal renin hypertension in obesity  opposed The third player in our study was urinary EGF/creatinine, which showed to be significantly lower in de T1DM group compared to the patients with obesity . The patients with diabetes had a lower, although not significant (p = 0.10) eGFR than the children with obesity. However, in the partial correlation analyses, no significant link between urinary EGF/creatinine and eGFR was withheld in any of the subgroups, indicating that the decreased urinary excretion of EGF in the diabetic subgroup was not merely a reflection of a lower eGFR. As published before, a decreasing urinary EGF might precede the decline in glomerular filtration rate in patients with T1DM .Strikingly, in boys with obesity as well as in boys with diabetes, the partial correlation analysis did reveal a significant, inverse link between urinary EGF/creatinine and both SBP and MAP. The inverse correlation between urinary EGF/creatinine and MAP in the male patients was confirmed in the multiple linear regression model, and appeared to be independent of disease (T1DM or obesity) and independent of eGFR. It is known that, besides its function as sensitive, pre-clinical biomarker for kidney function and tubulo-interstitial fibrosis, urinary EGF plays a role in regulating salt-sensitive hypertension. In hypertensive adults, salt-infusion resulted in an increased urinary expression of EGF, which in turn triggered urinary salt excretion through ENaC channels in the collecting duct . So a diOn the other hand, the significant difference between urinary EGF/creatinine levels in the children with obesity or diabetes, seems to confirm the difference in physiological regulation of blood pressure in the 2 groups, salt-sensitivity-driven in the obese versus renin-induced in the T1DM patients.Our study could not provide evidence for a direct link between renin and urinary EGF/creatinine. Of course, we should keep in mind that the measured serum renin is only a weak surrogate of the actual intrarenal RAS, and thus possibly not strong or reliable enough to uncover intrarenal actions between RAS and urinary EGF.Reviewing the literature, no direct effect of renin on urinary EGF has been demonstrated so far. In a few reports, the influence of the intrarenal RAS on urinary EGF has been indirectly studied by the effect of ACE-inhibition (ACE-I): in a rat model inducing RAS activation , a beneficial stimulatory effect of ACE-I on urinary EGF has been observed . In humaPulse pressure is the pulsatile component of the blood pressure, and reflects large arterial stiffness . A graduThe positive correlation between pulse pressure and plasma renin which we observed in the subpopulation of boys with either obesity or T1DM, does not provide an answer on which of these 2 actors triggers the other. A higher pulse pressure could theoretically be a consequence of RAS activation, but the lack of statistical evidence in the partial correlations  for any Complementary to pulse pressure, mean arterial pressure (MAP) represents the steady reflective component of blood pressure, and is determined by cardiac output and systemic vascular resistance of the small arteries . In ordeIn our study population, a significant inverse correlation between MAP and urinary EGF was observed in the subgroup of boys with either T1DM or obesity, independent of eGFR. So again, even before any obvious parameter of kidney decline (such as proteinuria or decrease in GFR) becomes apparent, a lower urinary EGF in our population seems to reflect the adverse effect of systemic blood pressure on glomerular integrity, preceding effective kidney decline.To the best of our knowledge, the observations in our study are the first to provide insight in the urinary excretion of EGF in children with obesity. Moreover, the association between PP and MAP on the one hand and the excretion of urinary EGF in boys with either obesity or T1DM on the other hand, also represents a novel finding that has not been reported before, not even in adults. So additionally to the known function of urinary EGF as an early prognostic biomarker for kidney damage, urinary EGF can also be considered as a sensitive alarm bell for preclinical undermined vascular health in obesity and T1DM at young age, long before the development of overt hypertension.Although no direct effect of renin on urinary EGF excretion could be demonstrated in this study, extrapolation of the results provides arguments for an either triggering and/or amplifying role of renin in the observed negative loop between blood pressure and urinary EGF in this pediatric population.In the prevention of vascular disease in children with diabetes or obesity, we could even argue that, besides physical exercise and dietary measurement, a lower threshold for ‘preventive’ ACE-inhibition should be envisaged in order to break the vicious circle between increased blood pressure and early signs of impaired vascular health and of glomerular damage. The current decisive algorithm of when to start ACE-inhibition and / or diuretics in children with diabetes or obesity  relies oOur findings also shed a new light on the definition of hypertension in childhood, which currently is still based on the upper segment of normal BP distribution , and notStrengths: By including two well-defined populations of lean children and adolescents with T1DM and children and adolescents with obesity and insulin resistance, we were able to investigate the relationship between renin, EGF and vascular status in two important patient groups of the metabolic spectrum. The young age implies a purer study population (compared to the adult population) with hardly any co-morbidity or bias from confounding factors of metabolic syndrome (obesity) or end organ damage (diabetes). The children and adolescents who participated in this study were not treated for hypertension. This rules out the possibility that drug treatment influenced the results. Moreover, they had a normal eGFR. Both blood pressure and renin production can be impaired in kidney failure , so if kLimitations: The study is limited by the fact that serum renin was used as a surrogate for intrarenal RAS. Both plasma and serum renin have been analysed in other studies as measures of renal RAS , 46, 47,Future perspectives: Future studies should focus on evaluating the individual evolution of urinary EGF, renin and blood pressure under the influence of weight loss in children and adolescents with obesity, or the effect of physical exercise in both children and adolescents with obesity or T1DM. It would be interesting to implement a roadmap in future studies in which the measurement of a mean blood pressure over 24h and overnight blood pressure measurement can be decided based on decreased urinary EGF levels. This might highlight the function of urinary EGF in selecting patients with nightly dipping and thus at risk of early cardiovascular morbidity.In boys with either obesity or diabetes, pulse pressure and mean arterial pressure are negatively associated with the functional integrity of the nephron , which is reflected by a decreased expression of urinary EGF. So in the prevention of cardiovascular morbidity in children with either obesity or diabetes, urinary EGF measurement could play an important role to monitor the earliest phase of impaired vascular health and of preclinical kidney damage.


Traditional monitoring addresses the symptoms, but not the underlying cause. Microcirculatory assessments complement macrocirculatory monitoring, and bladder-catheter-based technology offers a better representation of central microcirculation. Flap reconstruction surgeries involve demolitive and reconstructive phases, requiring optimal tissue perfusion. The literature lacks a consensus on macro–microcirculation coupling, and there is no agreement on the use of vasopressors during head and neck surgeries. Evidence-based guidelines are lacking, resulting in variations in vasopressor administration. (2) Methods: This is a 12-month observational, prospective study conducted in a single center. It aims to evaluate the impact of macro–microcirculation coupling on clinical complications in head and neck surgery. All consecutive patients undergoing oncologic surgery requiring flap reconstruction and meeting the inclusion criteria will be enrolled. The study will utilize standard hemodynamic monitoring and bladder catheterization for measuring urine output and temperature. (3) Conclusions: The study aims to evaluate the coupling of macro- and microcirculation in head and neck surgeries, assess hemodynamic parameters and microcirculatory changes, and investigate their association with postoperative complications. The results can enhance patient care and surgical outcomes. Major oncological demolitive–reconstructive surgeries of the head and neck region are characterized by prolonged operating times, during which patients experience significant biohumoural, cardiac, and vascular stress. This can lead to disturbances in both macrocirculatory and microcirculatory parameters. While these alterations are often addressed by administering fluids and vasoactive medications to correct the observed events, the underlying cause remains unaddressed. To better understand and potentially prevent these events, it is important to complete traditional macrocirculatory monitoring with microcirculatory assessment .Various devices, such as pulse contour monitors (PCM), are currently available for macrocirculatory monitoring with minimal impact on patient stress. Generally, PCMs use the calibrations and/or the pre-calculate data to obtain the flow of the patients ,3,4. On Demolitive surgery with flap reconstruction is the primary treatment for neoplastic conditions in the head and neck region. These procedures involve highly demolitive phases with intense nociceptive stimulation , followed by reconstructive phases with microsurgery, where nociceptive stimuli are reduced, and tissue perfusion must be optimally maintained to ensure successful microvascular anastomosis.The current literature lacks consensus regarding the coupling of macrocirculation with microcirculation, both for physiological and pharmacological confoundings . Many mi®, Vygon, Ecouen, France). The monitoring of the measured variables will be performed using the radial access technique.This is an observational, prospective, single-center, non-profit study. All consecutive patients undergoing oncological head and neck surgery with free flap reconstruction within a 12-month period  and meeting the inclusion criteria will be enrolled. The routine hemodynamic monitoring usually used for these type of surgery allows for the continuous recording of macrocirculatory parameters, including Pulse Rate Variability (PRV), Stroke Volume (SV), Cardiac Output (CO), Systemic Vascular Resistance (SVR), dp/dt max, and Cardiac Cycle Efficiency (CCE), using the Pressure Recording Analytical Method (PRAM) technique ,18. Thes®, VYGON, Ecouen, France) catheter to monitor urine output and temperature, the continuous monitoring of the microcirculation will also be achieved.Additionally, all patients undergoing demolitive–reconstructive surgery require the placement of a bladder catheter, which will remain in place during the postoperative period. This catheter will allow for the measurement of urine output and the patient’s temperature. By using the IKORUS  who are admitted to the geriatric intensive care unit in the postoperative period. Age 18–85 yo, BMI 15–35, eligible for this type of surgery multidisciplinary oncologic evaluation, informed consent, ASA status <IV.Exclusion criteria: Patients in whom cannulation of the peripheral artery would not be possible. Patients in whom the IKORUS catheter cannot be inserted  and who will require special catheters inserted directly by urologists. Patients who will not give their consent.Study outcomes: The study aims to evaluate the coupling between macro- and microcirculation and its potential impact on the intra- and postoperative clinical outcomes. The clinical outcomes will be classified according to the Clavien–Dindo classification during the hospital stay . AdditioSample size: All eligible cases within the study criteria will be included over a 12-month period. It is estimated that approximately 30 patients will undergo free flap reconstruction.For the definition of the hemodynamic parameters mentioned above, please refer to the literature on the subject, as they are well-known parameters . Here arHeart Rate Variability (HRV) is the fluctuation in time intervals between adjacent heartbeats generated by the interaction between the heart and the brain through the autonomic nervous system (sympathetic and parasympathetic), which acts dynamically and non-linearly. HRV is the result of interdependent regulatory systems that facilitate our adaptation to environmental and psychological variations ,21.PRV is the oscillation in time intervals between adjacent blood pressure waves, as the RR interval variations observed in HRV correspond to variations in the duration of the individual cardiac cycle described by the arterial pressure wave (pressor cardiac cycle). Some studies have compared these two methods of studying cardiac rhythm variability and confirmed a substantial correspondence between the two methods .CCE is a more recently introduced and less well-known hemodynamic parameter. It is an index of hemodynamic performance that reflects the energy expenditure sustained by the cardiovascular system (heart and circulation) to maintain a specific hemodynamic state. It is expressed as a number (ranging from +1 to −1) derived from the ratio between the work performed by the system and the energy expenditure necessary to maintain adequate homeostasis. Since no machine has 100% efficiency, no individual has a CCE equal to +1. To simplify, young and healthy individuals will have positive CCE values, older individuals will have lower positive values, and decompensated elderly individuals will have negative CCE values .The MostCare-up system allows for the real-time display of variables related to both macrocirculation and tissue perfusion. These variables are electronically acquired and stored within the device; this device records arterial pressure signals at a sampling rate of 1000 Hz. Beat-to-beat analysis is performed, and the results are saved in electronic format in the system’s internal memory. Two CSV files are generated, one containing the average values of the variables every 30 s, and the other containing the beat-to-beat values of all the variables displayed on the monitor. PRV values are recorded every 5 min in the file with the 30 s averages . Additionally, the beat-to-beat CSV file stored within the MostCare-up device allows for the offline analysis of PRV.The PCM method utilized in this study does not rely on external calibrations or pre-estimated data. It is implemented within the technology of the MostCare-up system, which electronically stores parameters such as pulse rate, arterial pressures, and flow. This enables the investigation of the relationship between macrocirculation and microcirculation, as well as the assessment of variations in the sympathetic–parasympathetic system through PRV. Both the macrocirculatory and microcirculatory systems are influenced by changes in the balance of the sympathetic–parasympathetic system induced by drugs and the surgical procedure.Healthy biological systems exhibit complex, nonlinear oscillations in the intervals between consecutive beats and blood pressure waves, reflecting their adaptability to environmental changes. Diseases can disrupt this complexity, resulting in reduced HRV and PRV, which are generally indicative of pathological conditions. However, certain pathological conditions, such as intramyocardial conduction abnormalities, can increase HRV and PRV. Optimal levels of HRV and PRV are associated with good health status, autoregulatory capacity, adaptability, and resilience .®, VYGON, Ecouen, France) will be employed. Alongside routine measurements of bladder temperature and urine collection, this special catheter enables the real-time visualization of saturation variations using a photodiode. These variations closely correlate with microcirculatory changes at the urethro-vesical junction [For microcirculation monitoring, the IKORUS system  positioned within a Foley catheter to monitor the urethral Perfusion Index (uPI). The PPG sensor makes direct contact with the urethral mucosa, capturing the pulsatile waveform. Employing an AC/DC ratio approach, the dedicated IKORUS monitor calculates the uPI, which demonstrates a close correlation with the standard perfusion index derived from pulse oximetry. The uPI represents the integral of pulsatile blood absorbance over a specific time window, yielding valuable insights into variations in total hemoglobin concentration weighted by tissue oxygen saturation. The monitor continuously displays the results of the uPI analysis at regular intervals of 10 s, 1 min, and 5 min, enabling the real-time monitoring of tissue perfusion.This approach provides a novel means for studying microcirculation within a central domain, facilitating a comprehensive understanding of the relationship between macro- and microcirculation as an integrated systemic response. The IKORUS system’s capability to measure the uPI offers valuable insights into tissue perfusion dynamics, enhancing our knowledge of microcirculatory changes in various clinical scenarios .In conclusion, the availability of minimally invasive hemodynamic monitoring systems, including PRV, based on PCM such as the upgraded version of MostCare-up, which is already in routine use in our institution for surgical patients, allows for the association of macrocirculatory variations, PRV, and hemodynamic profiles with the study of microcirculation using the IKORUS system during major demolitive–reconstructive surgeries in the head and neck region .p-values using Bonferroni corrections. Statistical significance will be set at a two-tailed p-value < 0.05.Continuous variables will be presented as mean (±standard deviation) or median (interquartile range: 25th–75th percentile), while categorical variables will be presented as numbers and percentages. Differences in hemodynamic parameters (macro and microcirculation) will be assessed at the following time points: baseline (T0), after anesthesia induction (T1), at the start of ischemia (T2), at the end of ischemia (T3), at the start of microsurgery (T4), at the end of microsurgery (T5), at the end of surgery (T6), at admission to ICU/SUB (T7), and on discharge from surgical ICU (T8) . StatistThe study aims to evaluate the coupling between macrocirculation and microcirculation in major demolitive–reconstructive surgeries of the head and neck region. By using pulse contour monitors and the IKORUS system, the study will assess hemodynamic parameters and microcirculatory changes during different phases of surgery. The results are expected to provide insights into the impact of these surgical procedures on both macro- and microcirculation. Additionally, the study will investigate the association between variations in hemodynamic parameters and the development of postoperative complications. These findings can contribute to improving patient care and optimizing surgical outcomes in this patient population.