The risk of post-transplantation adverse events did not differ between the two groups. Conclusions: Within the limits of its observational, retrospective design, this is the first study to suggest that nutritional management with sLPDs can safely delay the timing of preemptive kidney transplantation.Background: Although several studies suggest the benefit of a low-protein diet supplemented with amino acids and keto acids (sLPD) in delaying the initiation of hemodialysis, evidence on whether these nutritional approaches could delay the timing of preemptive transplantation is lacking. Methods: Retrospective nationwide cohort study, from Taiwan’s National Health Insurance Research Database. Patients having undergone a first preemptive kidney transplantation between 2001 and 2017 were identified and divided into two groups according to the presence of sLPD treatment or not. The primary outcome was the time between the diagnosis of advanced CKD and transplantation. Secondary outcomes were post-transplantation adverse events. Results: A total of 245 patients who received their first preemptive kidney transplantation were identified from the nationwide database; 63 of them had been on an sLPD prior to transplantation (sLPD group). The duration between the day of advanced CKD diagnosis and the day of transplantation was significantly longer in the sLPD group compared with the non-sLPD group (median duration: 345 vs. 220 days,  Uremia has been classically defined as a state of protein intoxication, and protein metabolism plays a major role in several pathophysiological alternations in advanced chronic kidney disease (CKD) ,2,3,4. TIn the 1970s, Walser et al. first reported that a very low-protein diet supplemented with ketoanalogues of essential amino acids can safely delay the progression of CKD . This trFurthermore, large observational studies have reported that patients on dietary treatment had a lower risk of death or infection after commencing dialysis ,20. MostAlthough there is growing evidence of the effect of sLPDs and sVLPDs in delaying the need to start dialysis, the issue regarding the need for preemptive kidney transplantation has not been fully explored. Indeed, preemptive kidney transplantation is a choice that may be of particular relevance to young patients, and in settings in which dialysis availability is restricted. To the best of our knowledge, only one paper has addressed this issue, reporting on a small series of cases successfully managed on a moderately restricted supplemented diet while waiting for preemptive pancreas-kidney transplantation . DelayinTaking advantage of the comprehensive nationwide medical records collected in Taiwan by the National Health Insurance Research Database (NHIRD), this study investigated the association between the use of sLPDs and the time to surgery among patients who received a preemptive kidney transplantation. In addition, this study aimed to check for eventual adverse effects of sLPDs on survival, and on the risk of major complications after transplantation.The novelty of the study, aimed at trying to answer an unanswered question, resides in the study population, relatively young and with low comorbidity, since the characteristics of the patients receiving kidney transplantations differed from those of the usual CKD patients receiving dialysis, in terms of age and comorbidity burden ,25,26.This retrospective cohort study utilized the National Health Insurance (NHI) Research Database (NHIRD) collected by the National Health Informatics Project (NHIP) and managed by the Health and Welfare Data Science Center (HWDC) of Taiwan. In March 1995, Taiwan launched a nationwide, single-payer, compulsory health care program called the NHI program, which covers approximately 99.8% of Taiwan’s population (nearly 24 million people in 2017). Comprehensive health care information on insured patients, including outpatient visits, disease diagnoses, drug prescriptions, and procedures, is included in the NHIRD. Disease diagnoses in the NHIRD follow the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) before 2015, and ICD-10-CM after 2016. Although examination reports and laboratory data are not available, the population-wide comprehensiveness is the strength of the database. Further information regarding the NHI and NHIRD is available in previous publications ,28,29. TPatients who received their first kidney transplantation between 2001 and 2017 were identified from the NHIRD, covering the entire Taiwanese population. The diagnosis code 55.69 (ICD-9-CM), Z94.0 (ICD-10-CM), the procedure code V42.0 (ICD-9-CM), 0TY00Z0, 0TY00Z2 (ICD-10-PCS) and the Taiwan reimbursement code 76020 were used in combination to identify kidney transplantation according to hospitalization data of NHIRD. The discharge date after hospitalization for kidney transplantation was defined as the index date. Patients who had a history of kidney transplantation or had received dialysis before the index date were excluded. Finally, patients whose information of advanced CKD was not available were also excluded .The kidney transplant donors were not identifiable from the NHIRD. Taiwan has implemented very strict regulations on organ donations, banning organ trafficking and trading; thus, the process of transplantation in Taiwan takes place without the exchange of money. In this study, patients receiving kidney transplantations were identified from the Taiwan’s NHIRD, which indicated that they all received their living donor kidney transplantations in Taiwan and followed the strict regulations.Patients with preemptive kidney transplantation were divided into two groups, depending on the use of ketoanalogue supplementation between the date of diagnosis of advanced CKD, and the date of kidney transplantation. The date of diagnosis of advanced CKD was defined as the date of first use of erythropoiesis- stimulating agents (ESAs) after at least three outpatient diagnoses of CKD. In accordance with the NHI reimbursement regulations, only patients with serum creatinine >6 mg/dL in combination with a hematocrit <28% qualify for ESA treatment. Therefore, this has been a commonly used method to identify patients with CKD stage 5 in previous NHIRD studies ,31. SimiThe covariates analyzed were age, sex, primary kidney disease, comorbid conditions , the Charlson Comorbidity Index (CCI), a history of hospitalization for events , and medications, namely anti-platelet agents, angiotensin converting enzyme inhibitors (ACEi), angiotensin receptor blockers (ARB), non-steroidal anti-inflammatory drugs (NSAID), statins, iron, vitamin D, calcium, oral hypoglycemic agents (OHA), and insulin. The diagnosis of comorbidities was defined as having at least two outpatient diagnoses or one inpatient diagnosis in the year preceding the index date. The history of hospitalization was traced back to 1995. Most of the diagnostic codes used in this study have been validated in previous NHIRD studies ,33. InfoThe main outcome was the duration between the date of advanced CKD diagnosis and the date of receiving kidney transplantation. The secondary outcomes were adverse events after kidney transplantation, including all-cause mortality, infection-associated hospitalization or death, newly diagnosed malignancy, osteoporosis-related fracture, new-onset diabetes mellitus, allograft failure requiring maintenance dialysis, and major cardiac and cerebrovascular events (MACCE). The latter were composed of acute myocardial infarction, acute ischemic stroke, intracerebral hemorrhage, heart failure hospitalization, and cardiovascular death. Information of date, place, and causes of mortality were available in the Taiwan Death Registry database which were included in HWDC. Components of MACCE were detected using a principal discharge diagnosis. Infection-related hospitalization, including sepsis, was detected using the principal or secondary discharge diagnoses. Osteoporosis-related fracture was identified on the basis of the principal diagnosis of a hospitalization or emergency visit. Newly diagnosed malignancy and allograft failure requiring maintenance dialysis were identified from the catastrophic illness certificate sub-database of the NHIRD. New-onset diabetes mellitus required at least two newly performed outpatient diagnoses with a prescription of oral hypoglycemic agents  or insulin.p value < 0.05 was considered statistically significant. All statistical analyses were performed using SAS version 9.4 .The mean duration from the day of advanced CKD to the day of transplantation was compared using the Mann–Whitney U-test between the sLPD and non-sLPD groups. The risk of adverse events (MACCE) or death  after transplantation was compared using a Cox proportional hazard model. The risk of non-fatal outcomes  after transplantation was compared using the Fine and Gray subdistribution hazard model which considered death during follow-up as a competing risk. To control for confounders, we created a propensity score in which the study group (sLPD vs. non-sLPD) was regressed on the patient’s characteristics, and we additionally adjusted for the propensity score in the survival analyses . Variablp = 0.022). Patients in the sLPD group were more likely to be male (58.7% vs. 44.5%), though this was not significant (p = 0.052). Except for age, there were no significant differences of the baseline characteristics between groups.A total of 245 patients who received their first preemptive kidney transplantation between 2001 and 2017 were identified from the NHIRD. Among them, 63 had been on a supplemented low protein diet (sLPD group), whereas the remaining 182 patients had not (non-sLPD group). p = 0.001). The median duration was 345 days (interquartile range: 195–700 days) in the sLPD group and 220 days in the non-sLPD group (interquartile range: 110–476 days), respectively.As illustrated in The mean follow-up duration after kidney transplantation was 6.7 years (standard deviation: 4.1 years) among the 245 patients. No significant difference between groups was found in terms of all-cause mortality, MACCE, infection-related hospitalization or death, newly diagnosed malignancy, new-onset diabetes mellitus, osteoporosis-related fracture, or allograft failure requiring dialysis .The importance of supplemented low-protein diets has been recently underlined in the new KDOQI guidelines, principally for their advantage of allowing a longer follow-up in the pre-dialysis phase . High-quOur study was performed in Taiwan, employing the NHIRD, a comprehensive nationwide database; it suggests that sLPDs may safely delay the timing of preemptive kidney transplantation among patients with advanced CKD.In Taiwan, patients who receive preemptive kidney transplantations account for a very small number of patients with ESRD. Only 245 recipients between 2001 and 2017 were identified. Even in Western countries, where organ donation is more popular than in Asian countries, preemptive kidney transplantation remains a niche ,38.Within the limits of a small number of cases, our study suggests that an sLPD treatment can significantly delay the timing of preemptive kidney transplantation, by a median of 125 days. Even more importantly, this study suggests that the most severe posttransplant adverse events, namely all-cause mortality, cardiovascular diseases, allograft failure requiring dialysis, new-onset diabetes mellitus, fracture, and malignancy, were not increased in patients who had been on a supplemented diet before kidney transplantation.Another point of interest is related to the characteristics of the study group: the mean age of our patients was 43.8 years, remarkably lower than the age of patients starting chronic dialysis (presently around 61 years), as reported in previous NHIRD-based studies ,20. FurtSeveral limitations of the current study should be acknowledged. First, the prevalence of preemptive kidney transplantations in Taiwan is lower than the global average. Therefore, even after using a nationwide database, the number of enrolled patients was limited in this study. Second, laboratory data, including serum albumin, creatinine, lipid profile, proteinuria, and hemoglobin, were not available in the NHIRD. In addition, the information on medical institutions and socioeconomic status of enrollees was not available in the dataset, and differences among these covariates may theoretically influence the results. Third, in an observational study, removing all potential confounders is impossible regardless of the study design, which may further bias the results. Namely, the possibility cannot be excluded that patients with a slower progression of CKD, or with better compliance, were selected. Fourth, this study was based on a Taiwanese database. Therefore, the results of the current study may not apply entirely to other populations because of cultural, dietary, and genetic differences. Fourth, although this study suggests that the use of sLPDs may delay the need of preemptive kidney transplantation, and without increasing short-term adverse events, it was not clear if delaying access to the transplantation would result in longer life expectancy or better quality of life. Lastly, the details of the diets were not available in the database, and the characteristics of the donors could not be identified.Most of these limitations are linked to the study design; however, a randomized control study would be hardly feasible, as well as possibly unsound from an ethical point of view, since diets need commitment and compliance is crucial ,41.Accepting these limitations, in conclusion, this study suggests that sLPDs have the potential to delay the timing of preemptive kidney transplantation, without increasing the risk of post-transplantation adverse events. Further well-designed randomized and prospective studies are warranted to verify these findings.


The Cox proportional hazard model was used to estimate hazard ratios (HRs) for the incidence of dementia in ARB users in the CKD population. During the 11-year follow-up period, 2207 dementia events were recorded; multivariate-adjusted hazard ratios for dementia by ARB usage and ARB usage per MPR were 0.578 (95% CI: 0.52–0.643) and 0.996 (95% CI: 0.995–0.998), respectively. This association was observed in almost all subgroups. Dose frequency effect of ARBs was noted; patients with higher MPRs of ARBs generally had higher protection from dementia. Patients with hypertension and CKD who received ARBs had a decreased risk of dementia. Protective effects of ARBs on dementia increased with the frequency of ARB use.Chronic kidney disease (CKD) is associated with dementia. Angiotensin receptor blockers (ARBs) have been widely used for delaying CKD progression; however, their effect on dementia prevention in patients with CKD remains unclear. We designed a retrospective cohort study to investigate the effects of ARBs on the incidence of dementia in patients with CKD. We selected 21,208 patients from the Taiwan nationwide database from 1 January 2006 to 31 December 2006. We identified ARB users ( Chronic kidney disease (CKD), a major health problem that causes considerable financial burden worldwide, can lead to end-stage renal disease (ESRD), resulting in the requirement of renal replacement therapy and contributing to increased cardiovascular mortality and morbidity ,2. The eCKD is commonly associated with hypertension as a comorbidity. Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor inhibitors (ARBs) are the preferred agents for treating hypertension in the CKD cohort due to their ability to delay the progression of CKD ,12. The ACEIs are associated with cough and a considerably but relatively low angioedema risk; the overall withdrawal rate due to adverse events is higher for ACEIs than ARBs . ACEIs cIn the present study, we examined the correlation between the usage of ARBs and the incidence of dementia in the CKD population by using real-world data from the National Health Insurance (NHI) Research Database (NHIRD).The present study used CKD thematic data from the NHIRD maintained by the Health and Welfare Data Science Center (HWDC), Ministry of Health and Welfare (MOHW), Taiwan. CKD was defined as having 3 outpatient diagnoses, with an interval of more than 4 weeks between each other within 1 year; the diagnosis of CKD includes 124 ICD-9-CM codes that were verified officially in the Chronic Kidney Disease Prevention Technology Research Project conducted by the Health Promotion Administration, Ministry of Health and Welfare. This includes CKD stages from 1 to 5 . The NHIn = 34,779). Patients who were previously diagnosed as having cancer, ESRD, dementia, or cerebrovascular disease; were receiving regular hemodialysis or peritoneal dialysis; had previously undergone renal transplantation; were aged <18 or >80 years; and had missing information were excluded. Finally, a total 21 379 patients with CKD and hypertension were included in this study  to estimate the degree to which the patients were prescribed ARBs during the follow-up period. The MPR is calculated as the sum of the days on which the drug was used during the observation period, divided by the total number of days in the observation period . In addiThe primary outcome of this study was the diagnosis of dementia, which was determined based on whether a patient was eligible for the NHI Administration IC Card for Severe Illness issued by the National Health Insurance Administration for dementia-related diagnoses. The data were analyzed from the index date (1 January 2007) to the first diagnosis of dementia, as defined previously, or the end of the study period (31 December 2017). This study used the criteria of the application for the NHI Administration IC Card for Severe Illness for dementia .t test for the means of continuous variables. The Kaplan–Meier method was used to estimate and plot dementia-free curves, which were evaluated using the log-rank test. A Cox proportional regression model was used to estimate hazard ratios (HRs) and 95% CIs for the risk of dementia. Both crude and multivariable variables were adjusted. The assumption of the proportional hazard was not violated when the interaction between time and the variables was examined. Moreover, we considered the death as a competing risk of dementia diagnosis in our analysis.Continuous variables are expressed as means ± standard deviations, whereas categorical variables are expressed as counts with proportions. Differences in the variables between the groups (ARB users vs nonusers) were determined using the chi-squared test for the proportions of continuous variables and the p value of < 0.05 was considered statistically significant.All statistical analyses were performed using SAS, version 9.4 . For all tests, a two-sided To examine the reliability of our findings, we used a separate regression model for modeling dichotomic ARB usage (yes vs no) or the MPR of ARBs as a function of the dementia event by using a modified stepwise procedure by using 4 modeling steps; the variables of demographic data, comorbidities, and medications were added into the models step by step. In addition, we analyzed the MPR of ARBs during the follow-up period to investigate the dose frequency effect of ARBs on the prevention of dementia. The Cochran–Armitage test was performed to examine the dose frequency effect of ARBs. We stratified the ARB users by the MPR and included them in the following groups: those with an MPR of ≤20%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, and >80%. We considered the group with an MPR of ≤20% as our reference point. Finally, we performed a subgroup analysis by age, sex, and comorbidities to test the consistency of the protective effect of ARBs on dementia in patients with CKD.We enrolled 21,208 patients with hypertension and CKD in the present study . The meap < 0.05). Moreover, the ARB users were more likely to be prescribed antiplatelet agents, insulin, statin, metformin, ACEIs, calcium channel blockers, and beta-blocker, whereas the ARB nonusers were more likely to be prescribed acetaminophen and benzodiazepine .A total of 2207 dementia events were noted during the 11-year observation period. The incidence rates of dementia in the ARB users and nonusers were 0.011 and 0.016 per person-year (PY), respectively. After adjusting for multivariable factors, only female sex; comorbidities, namely ischemic heart disease, diabetes mellitus, chronic heart failure, COPD, major depressive disorder, Parkinson’s disease, and insomnia; and the usage of antiplatelet agents, benzodiazepines, insulin, diuretics, and metformin were found to be significant risk factors for dementia. Significant protective effects of ARBs on the incidence of dementia were observed in both crude and adjusted analyses. Although we observed significant protective effects of ACEIs on the incidence of dementia, the results of crude analysis were not significant.2 = 68.56, p < 0.001; The results of the Kaplan–Meier analysis revealed that a significant difference in dementia-event-free curves between the ARB users and non-users (χp = 0.005).In this nationwide study, we observed that ARBs exerted a significant protective effect on the incidence of dementia in our hypertensive CKD cohort. Such protective effect exhibited a dose frequency effect pattern. Moreover, the protective effect of ARBs on dementia was consistently observed in almost all the subgroups. Using real-world data, our study extends the current knowledge in the field by indicating that ARB use can prevent dementia in the hypertensive CKD population.p = 0.003) in the presence of normal baseline cognitive function [p < 0.001) and vascular dementia  [Several studies have determined the relationship between ARB usage and cognitive decline or dementia apart from its benefit in blood pressure reduction. Some studies have reported significantly positive findings. In the GEMS trial, Yasar et al conducted a post-hoc analysis and found that in individuals aged between 75 and 96 years, ARB usage more significantly reduced the incidence of Alzheimer disease dementia compared with no antihypertensive medication use  . In thei< 0.001) . Chiu et< 0.001) . However< 0.001) . Another< 0.001) . n = 5513), Chiu et al reported that ARB use could prevent dementia in Taiwanese patients with CKD  [Kuan et al found that among patients with diabetes mellitus and hypertension, all-cause dementia risk was lower in those receiving ARBs  . Other s30–0.46) ; this fiCurrent guidelines recommend that ACEIs or ARBs should be used in patients with CKD who have high blood pressure ,28 becauApart from the effect of ARBs on dementia in the CKD population, we found that male sex was a protective factor for dementia; this finding is compatible with those of previous studies ,31. We oThe strengths of this study are as follows. First, because this was a nationwide population-based cohort study, its results can be generalized to the Chinese population. Second, our follow-up duration of 11 years was adequate to examine the primary outcomes. Moreover, we adjusted for some potential confounders; thus, the inference would be reliable. Finally, we minimized the overcoding of dementia by using the approved application for the catastrophic illness certificate of dementia in the NHI as our definition of dementia, and the diagnoses were made according to a strict protocol by neurologists or psychologists. Thus, the diagnoses of dementia were reliable in our study. Despite its strengths, our study still has some limitations. Information regarding potential confounding factors that are associated with dementia, including the body mass index, blood pressure, socioeconomic status, and lifestyle, was not available in the NHI database. Second, the severity of CKD stages could not be determined in the NHIRD, which might bias our inference. Finally, our study included only Taiwanese patients. Therefore, the results still need further verification before applying to other populations. Our study provides insights into the protective effects of ARB on dementia in the hypertensive CKD population in which ACEIs and ARBs are recommended for delaying CKD progression. Moreover, the protective effects of ARBs on dementia increased with an increase in the frequency of ARB use.


Helicobacter pylori infection in children as detected with an antigen stool test. We aimed to determine Helicobacter pylori prevalence in an adequately sized group of individuals with phenylketonuria and healthy subjects using the standard gold test (urea breath test). Further, we correlated Helicobacter pylori infection with metabolic control. The study comprised 103 individuals with phenylketonuria and 103 healthy subjects on whom a 13C urea breath test was performed. Blood phenylalanine levels in the preceding year were analysed. The infection rate did not differ between individuals with phenylketonuria and healthy subjects . The frequency of testing and phenylalanine concentrations of Helicobacter pylori-positive and Helicobacter pylori-negative patients with phenylketonuria did not differ . No associations were detected for body mass index or metabolic control. Forward stepwise regression models revealed that age (p = 0.0009–0.0016) was the only independent correlate of Helicobacter pylori infection with a relatively low fraction of the variability of the condition being explained . In conclusion, Helicobacter pylori infection in phenylketonuria is not more frequent than in the general population. Moreover, it does not depend on metabolic control.In a small preliminary study, phenylketonuria and poor metabolic control were suggested as risk factors for  Phenylketonuria (PKU) is an inborn error of metabolism that results in the abnormal metabolism of phenylalanine (Phe). Untreated or not adequately treated PKU can result in behavioural problems, mental disorders, intellectual disability and seizures. In general, the overall prognosis for patients with PKU is good ,2. Adequp ≤ 0.001 for all). The highest adjusted PR (p < 0.001 for both) were for renal insufficiency with hypertension  = 2.20 (1.60–3.00)) and overweight (PR (95% CI) = 2.06 (1.85–2.30)). Trefz et al. [Burton et al.  retrospeHelicobacter pylori (HP) infection in children with PKU than that in healthy peers (28.1% vs 9.4%). However, the control group of healthy subjects was very small. A dramatically higher frequency rate was documented in patients with mean Phe levels above 600 µmol/L for the preceding two years (51.8%) than those with lower concentrations (10.2%). Therefore, we aimed to determine the prevalence of HP in an adequately sized group of patients with PKU and thoroughly selected healthy peers. In addition, we correlated the presence of infection with individually defined metabolic control.Oztürk et al.  suggesteThe study comprised patients with PKU treated at five centres in Poland. The inclusion criteria included a diagnosis of classical PKU, continuous treatment from birth and willingness to participate in the study. The exclusion criteria were chronic diseases, which could influence Phe levels. All subjects with PKU were continuously receiving Phe-free formula. None of them were on additional treatment . None of the patients had a detectable neurological impairment or intellectual problems. All patients were attending normal schools, study or work. The assessment of metabolic control was based on Phe levels obtained within 12 months preceding the study. Phe concentrations were expressed as milligrams per decilitre (mg/dL). The number of tests, median Phe level and the percentage of abnormal Phe concentrations (>6 mg/dL up to 12 years of age and >10 mg/dL for older patients) were calculated for each patient according to recent recommendations . Similar13C isotope-labelled UBT. The 13CO2/12CO2 ratio measurement was carried out using a 13C-infrared isotope analyser system  as described earlier [In all patients and healthy controls, body weight and height were measured, and body mass index (BMI) was calculated. BMI was recalculated for patients younger than 18 years according to International Obesity Task Force values (BMI-IOTF corrected) . The pre earlier .The sample size was calculated with the assumption of a 15% difference  in the The mean and standard deviation (SD), median, and interquartile range (IQR) were calculated for all data. The Mann–Whitney U test was used to compare continuous variables between the groups. The Fisher’s test was used in the case of Boolean variables. The odds ratio (OR) was calculated to compare the frequency of HP infection in patients with PKU depending on age, BMI and metabolic control in the preceding year (according to (a) the median Phe concentration or (b) the percentage of abnormal Phe concentrations or the percentage of Phe concentrations higher, respectively, than (c) 6 mg/dL, (d) 10 mg/dL, (e) 12 mg/dL). Forward stepwise regression models were built to identify variables with the strongest relationship with HP infection. The models included: age, gender, BMI (IOTF adjusted) and metabolic control (as described for OR). Statistical significance was set at 0.05, and all tests were two-sided. Statistical analyses were carried out using Statistica 13.3 .The study was approved by the Bioethical Committee at Poznan University of Medical Sciences ; all the patients provided informed consent for their participation in this research project.p = 0.41).The characteristics of the studied subjects are summarised in p = 0.026 and p = 0.048, respectively). However, BMI values corrected for age  did not differ (p = 0.73). The frequency of testing and metabolic control of HP-positive and HP-negative patients in the preceding year were very similar . However, no differences were detected for nutritional status (BMI) or metabolic control  in the preceding year .Forward stepwise regression revealed that, exclusively, age was the independent correlate of HP infection. The five models explained a relatively low fraction of the variability of condition (Rn = 32) [n = 103) and matched healthy peers (n = 103).This is the first comparative study on the prevalence of HP infection in patients with PKU and healthy controls using a urea stable isotope breath test . We did n = 32) . In the n = 885 and n = 101) studied in Turkey , based upon a histopathological assessment [The infection rate in patients with PKU and HS in the present study was not different. Similarly, the prevalence of HP did not differ between selected age subgroups from our study and recent country-based publications comprising healthy peers . Żabka esessment ,21. AlthIn subjects with PKU, we did not find any association between metabolic control and the prevalence of HP infection. Our results significantly contradict the findings by Oztürk et al. , who fouThe strengths of our study are that it includes the largest studied population of patients with PKU and controls, the use of a non-invasive gold standard technique and well-defined metabolic control. The limitations comprise the lack of analysis of family history, socioeconomic status, potential risky behaviours   and the In conclusion, the HP infection rate in treated PKU is not higher than in the general population. Moreover, it does not depend on recent metabolic control.


Objective: To determine whether systemic vascular dysregulation (SVD) evaluated by nailfold capillaroscope and Flammer Syndrome Questionnaire (FSQ) affects retinal peripapillary microcirculation in non-glaucomatous healthy eyes at steady status.Methods: 120 healthy eyes from 63 non-glaucomatous subjects underwent Optical coherence tomography angiography (OCTA) after a rest of 30 minutes. Average retinal peripapillary capillary (RPC) vessel density (VD) and sectoral VD were automatically calculated, and peripapillary retinal nerve fiber layer thickness (RNFLT) was measured. Vasospastic diathesis was assessed using Flammer Syndrome Questionnaire (FSQ). Cold provocation test (CPT) was performed using nail-fold capillaroscope after OCTA. Positive CPT and a score of FSQ higher than 20% were necessary to determine a subject with SVD. Systemic and ocular parameters were compared between subjects with and without SVD.Results: In this study, heart rate (p = 0.042), ocular perfusion pressure (p = 0.014) and average RPC vessel density (p = 0.046) was significantly different between subjects with and without SVD determined by the combination of CPT and FSQ. Generalized estimation equation (GEE) showed lower VD was significantly associated with longer axial length , thinner peripapillary retinal nerve fiber layer thickness (RNFLT) , SVD determined by CPT and FSQ  and high blood pressure . In the superotemporal sector, multivariate model showed only SVD was associated with RPC vessel density .Conclusion: In subjects with SVD and non-glaucomatous healthy eyes, lower RPC vessel density in the superotemporal sector was observed. SVD determined by CPT and FSQ was significantly associated with attenuated retinal peripapillary microcirculation. Studies on ocular diseases relevant to vasospasms should consider the effects of SVD on the retinal peripapillary capillaries. Systemic vascular dysregulation (SVD) is a condition of inappropriate constriction or insufficient dilation of the microvasculature in response to irritation like cold provocation or emotional stress . People Nailfold capillaroscopy (NFC), a non-invasive convenient technology, can provide visual inspection of dynamic activities of the peripheral capillaries with high magnification and resolution for the observation of blood cells in the living body. Digital microcirculation was associated with retinal microcirculation . Cold prOptical coherence tomography angiography (OCTA) is a noninvasive effective device that can assess the retinal capillary network with high repeatability . Radial In this study, we used CPT combined with Flammer Syndrome Questionnaire , 20 to sAll the participants were recruited from an ongoing prospective study  approved by the Ethics Committee of Beijing Tongren Hospital (No. TRECKY2018-044) from November 2020 to February 2021. The subjects were volunteers from a neighbor community, staff of the hospital, or medical students. The study adhered the tenets of the declaration of Helsinki and all participants provided written informed consent after entering the research. The inclusion criteria were (1) subjects with non-glaucomatous healthy eyes confirmed by normal result of optical coherence tomography, Humphrey visual field test and non-contact tonometer; (2) no history of ocular trauma or intraocular surgery, any optic nerve or retinal pathology; (3) spherical diopter between +3.0 to −8 diopters (D). The exclusion criteria were (1) usage of anti-hypertensive drug and anticoagulant, (2) history of connective tissue diseases, diabetes mellitus, hypertension, hypercoagulation state, or other severe systemic diseases that could influence the retinal or digital circulation except for hyperlipidemia, (3) history of non-dominant hand trauma within 1 month, (4) poor clarity in site of nailfold, (5) optic disc tilt (ratio of the longest to the shortest diameter of the optic disc) higher than 1.3, (6) vitreous opacity or cataract and (7) glaucoma suspect.Systemic parameters were obtained on the day of testing including age, sex, systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR). Blood pressures were measured at the sitting position after 10 minutes of rest using an electronic hemopiezometer . High blood pressure (HBP) was defined as blood pressure higher than 140/90 mmHg on the visiting day. The mean arterial pressure (MAP) were calculated as the equation: MAP = DBP+ 1/3(SBP- DBP). Ocular perfusion pressure (OPP) were calculated as the equation: OPP = 2/3MAP – IOP. Comprehensive ophthalmic examination was performed for every participant including: optometry test, best corrected visual acuity, intra ocular pressure (IOP), axial length and central corneal thickness , fundus color photography , OCTA , OCT  and visual field test .Every participant was asked to answer the Flammer Syndrome Questionnaire (FSQ)  regardinThe cold provocation test (CPT) was performed by nailfold capillaroscopy  after the OCTA test to avoid temporary autonomic system irritation. Before the examination, the participants were asked to rest in the laboratory for at least 30 minutes at the room temperature of 25°C. To avoid the disturbance of morphology and obtain the most precise evaluation, the CPT test was performed on the fourth finger of the non-dominant hand after smearing with almond oil on the nailfold area. The videos of the nailfold capillaries were recorded at 300× magnification. After adjusting the hand to the same height of heart, the first video clip was recorded for 1 minute as contrast. Every part of the first row of capillaries along the nailfold was recorded for at least 5 seconds to observe baseline blood flow velocity. Later, the finger was immersed into 40°C warm water for 3 minutes and the second video clip was recorded for 1 minute. The recording method was the same as the first video clip. Last, the third video was recorded after immersion of −5°C ice saline for 1 minute. Each part of the first row of capillaries along the nailfold was quickly recorded to capture a blood flow standstill. The recording was ended until the blood flow recovered. Finally, the tested finger was gently covered by a soft cloth to recover to normal temperature after the end of the examination. Two observers (YQ.G and YX.S) identified whether there was a blood flow standstill (stops for more than 12 seconds) 2 weeks later after the videos were blinded to the clinical information.SVD was identified as long as a patient's FSQ score higher than 20% and have positive CPT at the same time.The OCTA images were obtained by a commercially available device . Every image contains 1 vertical and 1 horizontal priority of raster volumetric pattern with an 840 × 10 nm scan beam wavelength. Structural and blood flow information of high-definitional quality was acquired simultaneously at a 4.5 × 4.5 mm square centered on the optic disc. The optic disc margin was determined manually on the B-scan before measuring the parameters. The measurement of VD extends from the internal limiting membrane (ILM) to the posterior boundary of RNFL using system-provided AngioVue software (version 2017). Retinal vessel density was calculated as the percentage area of the vessel signals in a 750-μm-wide elliptical annulus stretching from the margin of the optic disc. The RNFLT was calculated in a band of 1 mm width extending from the optic disc boundary.Poor quality images were excluded: (1) strength index less than 47; (2) motion artifacts; (3) wrong RNFL segmentation.t-tests, Mann-Whitney U-test, or Chi-square test. Generalized estimation equation (GEE) was used to compare ocular variables and test the factors associated with VD accounting for inter-eye correlations. In univariate regression analysis, variables included in the model were as follows: age, sex, FSQ scores, SBP, DBP, HR MAP, OPP, IOP, axial length, CCT, average RNFLT, HBP, HBC, and SVD determined by FSQ and CPT. The multivariate model included parameters with P-value <1.5 in univariate regression analysis. Correlation analyzes between RPC vessel density and RNFLT, axial length, and FSQ score were performed using Spearman analysis. All statistical analyses were performed by Statistical Package for the Social Sciences . P values <0.05 were considered statistically significant. All data are presented as mean and standard deviation.Inter-observer agreement on the identification of positive CPT was assessed using kappa statistics (κ = 0.866). Any disagreement was solved by the third person (Y.Z). Comparisons of systemic parameters between 2 groups were performed using independent p = 0.056), diastolic pressure (p = 0.196), and mean arterial pressure (p = 0.056) between the SVD (+) and SVD (–) group. The SVD (+) has significantly lower heart rate (p = 0.042), higher FSQ scores (p < 0.001) and lower ocular perfusion pressure (p = 0.014) than SVD (–). There was no significant difference between the two groups in the spherical diopter, axial length, central cornea thickness, and intraocular pressure.This study included 63 participants, among which 15 were identified as SVD (+) by positive CPT and an FSQ score higher than 20% . The meap = 0.046). There was no significant difference in the sectoral comparison of the peripapillary RNFLT (p < 0.001).The mean peripapillary RNFLT of the SVD (–) and SVD (+) were 111.81 ± 10.39 and 113.43 ± 11.96 respectively (p = 0.562) . The avery RNFLT . Howeverp < 0.001), average RNFLT (p < 0.001) and SVD determined by CPT and FSQ scores (p = 0.046) were significantly associated with average peripapillary retinal vessel density in univariate model , average RNFLT , high blood pressure  and SVD  were significant factors associated with average peripapillary retinal vessel density in the final model.Using generalized estimation equation analysis, axial length (te model . Parametp = 0.036), and SVD determined by CPT and FSQ scores (p < 0.001) were significantly associated with peripapillary retinal vessel density in the superotemporal sector  was a significant factor associated with peripapillary retinal vessel density in the superotemporal sector in the final model.In the univariate model, axial length (l sector . Parametp = 0.02), and hyperlipidemia (p = 0.016) were significantly associated with peripapillary retinal vessel density in the inferotemporal sector      and axia< 0.001)  was sign= 0.019)  was signSince the OCTA test was performed after a rest for 30 minutes and before the cold provocation test, the lower RPC vessel density in this study can be interpreted as attenuate retinal capillaries associated with vasospastic predisposition rather than irritation-induced vasoconstriction of the retinal arterioles. There was a study that demonstrated a significant decrease in the retinal capillary flow of patients with Raynaud's phenomenon during the immersion of a hand in the ice water, which remained 17% reduced for at least 10 minutes after removal . The queTo be clear, several ocular factors have strong association with peripapillary vessel density in healthy eyes. Consistent with other studies –24, the p < 0.001) and SVD (p = 0.003) in the multivariate model. HBP patients in our study were subjects who presented blood pressure higher than 140/90 mmHg on the visiting day but without a medical history of hypertension. Temporary rise of blood pressure can cause retinal blood vessel changes by vasoconstrictive and malignant phases to control the volume of blood received by retinal capillary bed retinal arteriole  and blood flux index (p < 0.001), whereas RNFLT (p = 0.48) was not significantly different. Hou H (p = 0.014) but not in the inter-eye asymmetry of structural thickness (p = 0.943). The higher prevalence of migraine and cold extremities in open angle glaucoma, especially normal tension glaucoma, is also evidence of possible effect of vascular dysregulation on the retina  and SVD (–). This may imply that there was heterogeneous topographical peripapillary retinal blood supply in the SVD (+) group. Interestingly, the peripapillary superotemperal sector is one of the impressionable areas of glaucomatous damage. Several hints implied that impairment of retinal circulation might precede the loss of retinal nerve fiber layer loss. Chen CL  comparedt. Hou H  comparedH p = 0.0 but not e retina . HoweverCold provocation test by nailfold capillaroscopy as one of the objective examinations with binary outcome may occupy an important position in diagnosing vascular dysregulation. Different from complaints of patients regarding migraine, it is influenced little by confusion of depression or other types of cephalalgia, which might need further neurological examination for differential diagnosis. Its binary outcome can provide discriminable results, unlike other devices like dynamic vessel analyzes without a decision point. The difference of blood flow standstill time among healthy, normal tension glaucoma and high-tension glaucoma has been demonstrated before. The longer the standstill time of the blood flow, the more deteriorative the mean visual sensitivity was . Our stuThere were limitations in this study. First, bias resulted from a small sample size should be considered. Due to the lower prevalence of SVD in healthy population than in glaucoma, a bigger sample size is needed to collect data from healthy subjects with SVD. Second, other systemic factors including analysis of blood compositions and hemodynamic parameters were not included in this study. Further investigations are needed to include the influence of these factors. Third, this is a cross-sectional study. Prospective longitudinal studies are needed to clarify the causal relationship between SVD and peripapillary retinal circulation and possible structural changes.In conclusion, we found lower superficial peripapillary retinal vessel densities in subjects with systemic vascular dysregulation and non-glaucomatous healthy eyes, especially in the superotemporal sector. This is the first study to demonstrate that systemic vascular dysregulation may be associated with attenuated peripapillary retinal microcirculation on steady status. Thus, our study will be useful for further investigations of vascular impairment in ocular diseases associated with SVD. In addition, systemic vascular dysregulation profiling may be useful for early detection of the primary vascular impairment of the peripapillary vasculature.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.The studies involving human participants were reviewed and approved by the Ethics Committee of Beijing Tongren Hospital. The patients/participants provided their written informed consent to participate in this study.YG and NW: study design. HL and KC: data analysis. YG and YS: writing and data collection. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Thus, subnormothermic perfusion at 21 °C with Hemopure + 200 nM AP39 improves renal outcomes. Additionally, our novel blood-free model of ex vivo kidney preservation and reperfusion could be useful for studying other therapeutics.The use of blood for normothermic and subnormothermic kidney preservation hinders the translation of these approaches and promising therapeutics. This study evaluates whether adding hydrogen sulfide donor AP39 to Hemopure, a blood substitute, during subnormothermic perfusion improves kidney outcomes. After 30 min of renal pedicle clamping, porcine kidneys were treated to 4 h of static cold storage (SCS-4 °C) or subnormothermic perfusion at 21 °C with Hemopure (H-21 °C), Hemopure + 200 nM AP39 (H200nM-21 °C) or Hemopure + 1 µM AP39 (H1µM-21 °C). Then, kidneys were reperfused with Hemopure at 37 °C for 4 h with metabolic support. Perfusate composition, tissue oxygenation, urinalysis and histopathology were analyzed. During preservation, the H200nM-21 °C group exhibited significantly higher urine output than the other groups and significantly higher tissue oxygenation than the H1µM-21 °C group at 1 h and 2h. During reperfusion, the H200nM-21 °C group exhibited significantly higher urine output and lower urine protein than the other groups. Additionally, the H200nM-21 °C group exhibited higher perfusate pO Kidney transplantation is the preferred treatment for end-stage kidney disease (ESKD) because it improves long-term survival and quality of life compared to hemodialysis ,2,3. How2S), a gasotransmitter with cytoprotective properties, to preservation solutions [2S donor, AP39, to cold preservation solution improves renal and cardiac graft outcomes [Several strategies have been explored to improve cold preservation methods, such as the addition of hydrogen sulfide , can solve the problem of oxygenation and circumvent the need for blood in the context of normothermic and subnormothermic preservation. One promising candidate is Hemopure , which is made of highly purified bovine hemoglobin ,23. Clin2S donor, AP39, to University of Wisconsin (UW) solution, a preservation solution that is commonly used for SCS, made it suitable for subnormothermic preservation [While recent evidence supports the use of Hemopure for kidney preservation, its potential as a platform to deliver therapeutics that could further enhance renal graft outcomes remains unexplored. We have previously shown that adding Hervation . Additioervation . In this2, pH and lactate levels  and at the end of reperfusion to evaluate differences in gross morphology . The imae levels , Table 1ch group A. The H1ch group B. Furthech group C, which ch group B. None oTo evaluate the impact of the treatments on organ perfusion, tissue oxygenation was measured hourly during preservation and reperfusion , Table 2To evaluate kidney function, urine output was measured during both halves of the experiment and urinalysis was performed . During To evaluate apoptotic tissue injury, kidney sections were stained with TUNEL A and scoThis study establishes a novel blood-free model of ex vivo kidney preservation and reperfusion using Hemopure, a hemoglobin-based oxygen carrier that serves as a blood substitute. Using this model, we show that subnormothermic perfusion of DCD pig kidneys at 21 °C with AP39-supplemented Hemopure improves graft function and reduces tissue injury compared to SCS and subnormothermic perfusion with Hemopure alone.The primary finding of this study is that the H200nM-21 °C group displayed significantly improved or comparable outcomes relative to the SCS-4 °C group, which reflects the clinical standard of care for kidney preservation. Importantly, the H200nM-21 °C group exhibited significantly higher urine output than the SCS-4 °C group during reperfusion. The immediacy of post-operative urine output is a critical renal transplant outcome, as it determines whether dialysis is needed to address delayed graft function. In 2018, Hosgood et al.  successfIn addition to showing that our novel approach matches the clinical standard of care, this study strengthens the evidence supporting the use of 200 nM AP39 in kidney preservation. We have previously shown that prolonged SCS in UW + 200 nM AP39 improves recipient outcomes in an in vivo model of murine kidney transplantation . AdditioOne of the focal points of this study is our novel blood-free model of preservation and reperfusion. While Hemopure has been used for normothermic and subnormothermic kidney preservation before ,20,26, w2, pH and Lactate) with our iSTAT analysis platform since it was designed for use with blood (not Hemopure) at normothermic temperatures rather than subnormothermic temperatures. Our attempt to use the IDEXX analysis platform to detect perfusate levels during preservation also failed. Moreover, our study lacks a number of controls such as cold or subnormothermic perfusion group without Hemopure. This is because the high cost (CAD 5000/pig experiment) limits the number of groups we could evaluate. Thus, we designed our study around the premise of comparing the outcomes of our novel approach to that of SCS, which is the clinical standard of care, and perfusion with Hemopure alone, which is the control for the effects of temperature and oxygenated perfusion. Lastly, while perfusion was kept at constant pressure by adjusting the flow, we are unable to report flow data. On the other hand, our novel perfusion model has several limitations. Although we used Hemopure to establish a blood-free model of preservation and reperfusion, the lack of white blood cells in our perfusate largely excludes the inflammatory component of subnormothermic preservation as well as reperfusion with blood. Additionally, the pigmented nature of Hemopure, due to the hemoglobin, prevented the use of colorimetric and fluorescent assays to detect inflammatory markers in the perfusate. Furthermore, pairs of kidneys were connected to the same circuit and perfused using a shared Hemopure reservoir due to the limitation of having only one organ perfusion pump. Although we collected urine output separately for each kidney, the perfusate parameter readings were less robust, as only one reading was obtained due to the perfusate being shared by pairs of kidneys. Moreover, we were unable to detect perfusate parameters , purchased from a regional farm, were tranquilized and routinely prepped for surgery. A midline incision was used to expose the kidneys. Following intravenous infusion of 10,000 U of heparin, the renal pedicles were clamped in situ for 30 min to induce warm ischemia and mimic DCD injury. The complete cessation of renal blood flow replicates an extreme clinical DCD scenario where no oxygen is being supplied to the kidneys. This approach has been used in many other studies within the field and previous studies by our center. During the clamping period, the ureters and arteries were cannulated to facilitate ex vivo perfusion and urine collection. Subsequently, both kidneys were nephrectomized and the donor animal was euthanized. Surgeries were performed by transplant fellows at University Hospital, London, Canada. All procedures were approved by the University of Western Ontario’s Animal Use Committee  on 28 March 2019.The ex vivo perfusion setup used in this study is identical to the setup used in previous studies ,19,20 by®, USA) on ice for 4 h (SCS-4 °C), which reflects the clinical standard of care. The second group of kidneys were flushed with HTK solution and treated to 4 h of subnormothermic perfusion at 21 °C with Hemopure (H-21 °C). The third group of kidneys were flushed with HTK solution + 200 nM AP39 and treated to 4 h of subnormothermic perfusion at 21 °C with Hemopure + 200 nM AP39 (H200nM-21 °C). The fourth group of kidneys were flushed with HTK solution + 1 µM AP39 and treated to 4 h of subnormothermic perfusion at 21 °C with Hemopure + 1 µM AP39 (H1µM-21 °C). For the three preservation treatments involving subnormothermic perfusion, urine output was recorded hourly and the volume loss was replaced with the addition of PlasmaLyte. Additionally, tissue oxygenation was measured hourly using the InSpectra StO2 Spot Check Tissue Perfusion Monitor .Pairs of kidneys were assigned to one of four treatment groups . The firFollowing 4 h of preservation, kidneys were reperfused for 4 h using our novel blood-free reperfusion model . Due to 2 Spot Check Tissue Perfusion Monitor . Additionally, perfusate parameters  were measured using the iSTAT Handheld Blood Analyzer  to allow for relative comparison between groups. Sodium bicarbonate was injected as needed to adjust perfusate pH. After 4 h of reperfusion, kidney sections (cortex and medulla) were cut and stored in formalin for histopathological analyses.During reperfusion, urine samples were collected, and urine output was recorded hourly. The volume lost was replaced with the addition of PlasmaLyte. Tissue oxygenation was measured hourly using the InSpectra StOHydrogen sulfide donor molecule, AP39, synthesized in-house by Prof. Whiteman , was disg. Urine protein and creatinine levels were analyzed using the IDEXX Urine Analyzer , but creatinine values remained undetectable.Most of the urine samples collected were heavily pigmented, due to the presence of hemoglobin from the Hemopure, which prevented the use of conventional urinalysis methods. A 1:3 dilution of urine in Hemoglobind  allowed us to obtain clearer urine samples after 10 min of vigorous shaking and centrifugation at 12,000× Formalin-fixed kidney sections, including cortex and medulla, were embedded in paraffin and mounted onto microscope slides. The sections were stained with Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and Hematoxylin and Eosin (H&E) to determine the level of apoptosis and acute tubular necrosis, respectively. TUNEL and H&E imaging was done using the Nikon Instruments Eclipse 90i digital microscope at 10× magnification . Both sets of slides were scored by a blinded renal pathologist as per the following scheme: 1 = <11%, 2 = 11–24%, 3 = 25–45%, 4 = 46–75%, 5 = >75%.n values in certain groups. One-way or two-way ANOVA followed by Tukey’s post-hoc test was used for comparisons of three or more experimental groups. Statistical significance was accepted at p < 0.05.GraphPad Prism v9.0  was used to create graphs and conduct statistical analyses. SEM is graphed as it accounts for the impact of varying The data reported in this study are a part of a US patent application  that is pending approval. Additionally, Prof. Matthew Whiteman and the University of Exeter have intellectual property (patent filings) related to hydrogen sulfide delivery molecules and their therapeutic use.


Outcome variables included changes in blood pressure levels, triglycerides, HDL cholesterol, fasting glucose, body mass index, waist/hip ratio, abdominal obesity, and metabolic syndrome risk score, health-related quality of life, and depressive symptoms. Longitudinal multilevel analyses assessed the effects of the BC and ER programs and the level of adherence of the ER on clinical, anthropometric, and mental health variables, models were linear for continuous variables, and logistic for dichotomous variables. Differences were observed in triglycerides, BMI, metabolic risk scores variables, and depressive symptoms among ER and BC programs. In addition, differences in the ER group were observed according to the level of adherence in blood pressure levels, waist circumference and waist/hip ratio, depressive symptoms, and the mental health component of health-related quality of life. An ER program in comparison to a BC intervention is promoting changes in some specific health indicators of hypertensive patients, showing the usefulness of these PA programs in primary health care facilities.Among the modifiable health behaviors, physical activity (PA) promotion has been one of the challenges in primary care, particularly how to translate the results of proven interventions and implement them in the real world. This study was aimed to compare whether two programs designed for hypertensive patients achieve changes in clinical and anthropometric variables, quality of life, and depressive symptoms; and if higher levels of adherence to one of the interventions using an exercise referral (ER) approach achieved better health outcomes. Pragmatic cluster randomized trials were carried out in four Primary Health Care Units (PHCUs). Physicians in the PHCUs identified hypertensive patients and assessed whether they were eligible to be part of this trial. Each center was randomized to a brief PA counseling (BC,  In the global health community, one of the greatest challenges is how to translate the results of proven interventions and implement them in the real world. Part of this challenge resides on the individuals themselves who are responsible for making these recommendations.The efficacy of interventions to reduce high-risk behaviors through healthy lifestyle promotion, including healthy food habits, smoking cessation, and increased physical activity (PA) levels, has been determined in randomized or quasi-randomized controlled trials . HoweverAmong the modifiable health behaviors, the promotion of PA has been one of the challenges in primary care. Estimations indicated that not meeting PA recommendations is responsible for more than 5 million deaths globally each year . AlthougFew studies have evaluated the impact of the levels of adherence of PA interventions carried out in primary health care, and its effects on participants physical health, anthropometry, perception of their quality of life, as well as mental well-being. The aim of this study was to compare if two PA programs designed for increasing the PA levels of hypertensive patients achieve changes in clinical and anthropometric variables, quality of life, and depressive symptoms between baseline, 16 and 24 weeks; and if higher levels of adherence to one of the interventions using an exercise referral (ER) approach achieve better outcomes.Cluster randomized trial, with Primary Health Care Units(PHCUs) as the unit of randomization and hypertensive patients as the unit of assessment.The physicians in all PHCUs identified hypertensive patients and assessed that they met the established criteria. Study design and details of the recruitment process are described elsewhere .Trained staff in all the PHCUs used the eligibility criteria to warrant both that the practice of PA was safe for all participants, and the conditions to apply the behavioral theory-based intervention: women and men with IMSS affiliation, between 35 and 70 years old, less than 5 years from hypertension diagnosis, and/or without drug treatment (according to JNC 7 criteria) , self-reHypertensive patients complying with the inclusion criteria were not eligible if they reported a high PA level (>300 min a week of moderate to vigorous intensity), and have previously attended a PA program at IMSS facilities.The Mexican Social Security Institute (IMSS) includes facilities for primary, secondary, and tertiary health care services as well as available resources designed to develop PA programs  called Social Security Centers (SCC). The screening assessment and the exercise reference by physicians were carried out in PHCUs, while the PA program exercise program was performed during 16 weeks at SCCs. The functioning and staff of the SCCs were described previously.The sample size estimation was based on the goal of increasing the percentage of hypertensive patients who are physically active from 17 to 37%, the proportion that has been shown in preliminary assessments. An increase in compliance with PA recommendations of 20% showed whether the intervention was effective. The proportion is consistent with the effectiveness level tested in other studies . Thus, tTo avoid contamination randomization was conducted with IMSS facilities PHCUs located on average 5.5 kilometers (kms) from the place where patients were referred , within the urban area of the city, and had public transportation available, average transfer time being 20 to 30 min. The four PHCUs were randomized into an intervention group called exercise referral (ER) (two centers) and a BC (two centers) using sealed envelopes by a health researcher who was not involved in this study.The recruitment process took place from September 2011 to March 2012, in four PHCUs; 506 hypertensive patients were identified and assessed by 108 PHC physicians who took part in the four PHCUs that were randomized as the study groups. The activities of the physicians during the daily consultation to identify potential participants were expressed in a previous publication . Figure The main health outcomes were: systolic and diastolic blood pressure levels, triglycerides, HDL cholesterol, fasting glucose, body mass index, weight, waist/hip ratio, and metabolic syndrome risk score, health-related quality of life, and depressive symptoms.Follow-up measurements were carried out at the end of the intervention (16 weeks) for both ER and BC groups, while the sustainability of intervention effects was assessed 24 weeks after the beginning of the study. In addition, differences in health outcomes were observed among hypertensive patients belonging to the ER group who achieved 50% of adherence to the PA program, which means they attended at least 24 planned PA sessions or more.(a)Blood pressure levels measured with a digital instrument following criteria established by the JNC 7 ;(b)Biochemical markers measured according to the procedures of the International Federation of Clinical Chemistry and Laboratory Medicine : (1) Fas(c)2), overweight (BMI = 25–29.9 kg/m2) and obese (BMI = > 30 kg/m2)  weight, measured with TANITA electronic scale, with participants wearing minimal clothes and without shoes; (2) Body Mass Index (BMI), was calculated dividing kilograms by height in meters squared. The data obtained were categorized according to the following criteria: normal (BMI = 18.5–24.9 kg/m0 kg/m2) ; (3) wai0 kg/m2)  and wais(d)Physical and psychological measurements: (1) health-related quality of life (HRQoL), measured through the short form of 12 items (SF-12), considering two components physical (PCS) and mental (MCS) . The Phy(2) Symptoms of depression were measured with the Center for Epidemiologic Studies–Depression Scale, (CESD), this version included 20 items which are summarized to create the scale, the score range is from 0 to 60, higher scores are indicating a certain level of depressive symptomatology .Metabolic Syndrome Risk Score (MetSyn): Abdominal obesity; elevated fasting glucose as 100 mg/dL, triglycerides as 150 mg/dL; Cholesterol HDL <40 mg/dL and blood pressure as a resting systolic 130 mm Hg or a resting diastolic 85 mm Hg, which corresponds to a mean arterial blood pressure (MABP) of 100 mm Hg. For each MetSyn component, the clinical cutoff value was subtracted from the individual’s value and then divided by the population’s standard deviation (SD). The standardized score for each MetSyn component was then averaged to derive a clustered CVD risk score relative to IDF MetSyn definition (CVD risk score). To compile the CVD risk score with units of SD, positively skewed variables (FG and TG) were previously transformed .Physical activity: PA levels were assessed at baseline, T1 (16 weeks) and T2 (24 weeks), to determine changes in the following: percentage of participants meeting the PA recommendation, minutes of moderate and vigorous PA performed per week, and minutes per day of sedentary behavior. PA was measured by self-report (indirect methods) and accelerometry (direct methods). Self-reported (subjective) through the short version of the International Physical Activity Questionnaire (IPAQ) , and objEach patient’s accelerometer record was analyzed in terms of time (in minutes) to perform PA of moderate to vigorous intensity per day and then calculate the average time spent (in minutes) of PA during the week. Using this data, patients were categorized as complying or not complying with PA recommendation, 6 (150 min of PA at moderate to vigorous intensity a week) at baseline, T1 and T2, in both IG and CG. Additionally, PA measures were complemented with a PA log that participants completed every week.Socio-demographic variables included age, age group, gender, marital status, and main activity.We defined as confounding and modifier variables the following: met PA recommendation measured by both self-reported and objectively with the accelerometer, weight, and BMI at baseline, age, gender, education, main activity.The intervention was based on the assumptions of the Transtheoretical Model and Social Cognitive Theory . The infDuring the first session, a functional capacity assessment and PA prescription were carried out. The program of 16 weeks had 48 sessions of 60 min, a frequency of three times per week, and an average intensity of moderate to vigorous. Three levels or stages during the 16 weeks of the PA program were developed: Level 1, or Induction; Level 2, or Development; and Level 3, or Maintenance. In addition, each session consisted of three phases of exercise: warm-up and flexibility phase; aerobics phase, and recovery phase. The ER program had 48 sessions of planned PA. We defined a high level of adherence (>50%) to those patients who attended at least half of the sessions (24 sessions or more), while a low level of adherence (<50%) was determined for patients who attended less than 24 sessions of the PA program.At the end of the 16 weeks of the program, PA specialists encouraged the participants to continue with PA practice at the CSS facilities (at no cost for the following 6 months) or practice regular PA during leisure time in their preferred facilities, but without financial support from IMSS.Participants belonging to PHCUs were randomized to the control group after inclusion criteria were confirmed. Additionally, written and verbal information about the health benefits of PA practice, and how to increase PA levels in a safe way was distributed to the participants. All the patients in this group continued receiving their usual care at PHCU facilities but were also informed about the health benefits of PA and a balanced diet, and how to safely increase PA levels during free time, their participation in this PA program did not include planned PA sessions, therefore adherence to PA program was not estimated. In addition, they were invited to undergo two subsequent measurements at the PHCU facilities, at 16 weeks and 24 to the baseline measurement. Monthly contact with participants was carried out during their consultation at PHCUs.Analyses were carried out according to an intention to treat analysis.T-test or analysis of variance (ANOVA) was conducted, while U of Mann Whitney was used to compare variables with not normal distribution.A baseline comparability analysis was carried out among the ER and BC, in relation to the variables studied during the baseline, 16 and 14 weeks. To compare means, a Due randomization took place in PHCUs and multilevel analyses were used. Longitudinal multilevel analyses were developed to account for the three measurements between intervention and control groups, thus the three follow-up measurements of the outcome measure concerned were defined as dependent variables. The multilevel model allowed taking into account the clustering of individuals within PHCUs through the next levels: (1) the individual and (2) PHCUs. These models were linear for all outcome variables including blood pressure, biochemical and anthropometric measurements, depressive symptoms, the physical and mental component of quality of life, and metabolic syndrome risk score. The Wald statistic was used to determine the statistical significance of intervention effects and level of compliance on the outcome variables.For the variables, the models were adjusted for confounding or modifier effects variables following the next steps: (1) crude model, adjusted by group (intervention/control), stage (time), and baseline value of the outcome measure concerned, the latest to avoid a regression bias to the estimated mean ; (2) AddThe National Research Commission and Ethics Committee at Mexican Social Security Institution and National Institute of Public Health in Mexico, approved this study and all its procedures, as stated before .The characteristics of the study population according to meeting PA recommendations at 16 (T1) and 24 (T2) weeks of follow-up in the BC and the ER groups and by the level of adherence for the ER are shown in The percentage change observed in systolic and diastolic blood pressure was not statistically significantly different in longitudinal multilevel analyses, although blood pressure levels decreased in the BC group and remained at the same levels in the ER group. We also observed a statistically significant difference in weight and in metabolic syndrome risk score, whose values in participants in the ER group decreased among basal, T1 (16 weeks), and T2 (24 weeks) of follow-up, however, difference by level of compliance was not observed in biological  variables .Longitudinal changes in depressive symptoms and quality of life showed differences statistically significant among Baseline, T1, and T2 in depressive symptoms among the ER and BC groups, and by level of compliance >50% of the ER group in the mean of the mental health component of quality of life .p-value < 0.05.Multilevel longitudinal analyses according to intention to treat analysis showed statistically significant changes in the biochemical variables measured in the study among ER and BC groups: triglycerides β adjusted = −14.1  and Metabolic syndrome risk score β adjusted = −3.5 , . Anthropp < 0.05, after adjusting for group, stage (time), and baseline value of outcome measure , waist circumference β adjusted −1.8 , depressive symptoms β adjusted −1.66  and the score of the Mental Health Component (MCS) of quality of life,  measure .The results of this study show firstly the feasibility of carrying out an exercise-referral scheme intervention in the context of a social security institution in an upper-middle-income country like Mexico. We observed that both PA programs achieved changes in clinical indicators as triglycerides and anthropometric values Body Mass Index and Metabolic syndrome risk score. While higher levels of adherence of patients who got the ER scheme to increase PA levels accomplished better outcomes in the Mental Health Component in comparison with hypertensive patients who had a lower level of adherence to the ER scheme. In comparison to the BC group, the ER and higher levels of adherence achieved both changes in the perception of social functioning.Backgrounds in a similar context are lacking, and thus the findings of this cluster-randomized trial would be helpful to encourage the design of programs and strategies to increase PA among patients with chronic diseases in a context such as Mexico.Physical activity promotion through an exercise-referral scheme, compared to the control group with BC to encourage PA, showed findings which are according to previous studies of effectiveness in which the BC has achieved increased the PA levels compared to the exercise-referral scheme ; or as hThe differences observed in clinical variables such as blood pressure levels, triglycerides, and fasting glucose among those who reported higher levels of adherence to the intervention could be supported by findings in previous studies with similar approaches in which a “Hawthorne” effect could have been present. In fact, the findings of improved clinical and anthropometric factors have been reported in studies carried out mostly in high-income countries .In a way consistent with the evidence generated in studies of exercise-referral schemes, the ability of the intervention to increase physical health outcomes was low . The eliLikewise, in the follow-up, the rates of participation among the ER and BC were different, while the control group observed a follow-up rate at 24 weeks of 90%, the intervention group saw a decrease to 62%. Independent of changes of behavior and contrary to expectations, a behavioral theory-based intervention carried out with an exercise-referral scheme had less impact hooking the subjects as participants in the study. Studies in primary health care settings have suggested that motivational activities including the provision of exercise are more effective than interventions with only exercise aims . HoweverThe modest effect of an exercise-referral scheme using a behavioral theory-based approach to achieve a recommended level, as stated before in National Exercise-Referral Schemes depends on the level of adherence; one of the most questionable issues of exercise-referral schemes. In this cluster trial, we set a goal of 50% of compliance (attendance of at least 24 sessions) which resulted in 78.2% of participants who began the exercise program achieving this level of adherence; a top-level compared to the levels observed in other trials. In This cluster-randomized trial has several strengths. To our knowledge, this is perhaps the first study to carry out an intervention to increase PA through an exercise-referral scheme among sedentary patients with a recent diagnosis of hypertension; in an upper-middle-income country.This study used a control group with the same measurements throughout the study, which allowed for the assessment of the intervention effects from several dimensions during the three stages of the study. Particularly it had the strength of assessing PA levels through an objective method, thereby reducing the bias of self-reported PA measures.It measured the sustainability effects and the level of adherence to the intervention, reinforcing the capacity of measuring the effects carefully. The trial was clustered by practice to reduce the risk of the intervention being contaminated; however, this mechanism of allocation was not enough to avoid changes in lifestyles in the control group, thus changes in outcome variables were observed in the BC group, which as it has been mentioned received a less intensive PA program under a BC approach, influencing not only in PA variables but in other lifestyles, findings that have been previously reported . FinallyThis intervention achieved changes among the hypertensive patients who participated in the exercise referral program in comparison with those in the BC group. Changes observed among PA programs at time 0, 16, and 24 weeks pointed out a better performance of the ER in comparison to the BC program in clinical indicators and anthropometric variables, such as triglycerides and the Metabolic syndrome risk score, BMI, and also depression symptoms. About the objective aimed to determine differences in the outcome variables according to level of adherence to the exercise referral scheme, we observed that whether in clinical outcomes as blood pressure levels, waist circumference, and the rate waist/hip and in depressive symptoms and health-related quality of life perception of hypertensive patients who achieved at least 50% adherence to the ER have a better outcome than those with a lower level of adherence. However, although these results did not keep statistical significance in the adjusted models, they at least allow us to glimpse the benefits of PA when programs achieved higher attachment, which could be an important finding to promote a higher engagement in PA programs in the population with chronic conditions.The original contributions presented in the study are included in the article/The studies involving human participants were reviewed and approved by The National Research Commission and Ethics Committee at Mexican Social Security Institution, and National Institute of Public Health in Mexico, approved this study and all its procedures. The patients/participants provided their written informed consent to participate in this study.KG-C wrote the original protocol and manuscript, collected the data, designed statistical models, and performed analyses. CG-P contributed to the original protocol and wrote the first and final draft. NS-D-S wrote the first draft with contributions from KG-C. JS contributed to the original protocol and wrote the first draft with contributions from KG-C. FL contributed to the original protocol, supported in developing the strategy to analyze the data, and wrote the first draft with contributions from KG-C. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


The current concept of healthcare incites a more personalized treatment of diseases. To this aim, biomarkers are needed to improve decision-making facing chronic kidney disease (CKD) patients. Prognostic markers provided by real-world  evidence are proposed in this Special Issue entitled “Biomarkers in Chronic Kidney Disease”, with the intention to identify high-risk patients. These markers do not target measurable parameters in patients but clinical endpoints that may be in turn transformed to benefits under the effect of future interventions. Healthcare is changing. Currently and more and more, there is an urgent need for targeted or more personalized therapies, which should be especially addressed to the most susceptible patient populations. Shifting the focus from a one-size-fits-all system to one that is patient-tailored, must provide clinicians with the right tools to treat the right patient with the right dose of the right medicine (or medicines) at the right time. In this context, biomarkers should allow the evaluation and improve the impact of the interventions destined to chronic kidney disease (CKD) patients, with the objective to achieve the most clinically rewarding outcomes for them . ImportaA complicated decision-making process may be facilitated if specific markers for CKD patients are available. The common markers used in non-CKD populations are not useful for managing individuals with kidney function deterioration. A paradoxical effect from such markers leads to confusion, it is already noticeable among patients with moderated kidney function deterioration, and clinically clear in the end-stage of kidney disease (ESKD) .According to the definition of the National Institute for Health (NIH), a biomarker is “a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes or pharmacological responses to a therapeutic intervention” . This brIn addition, biomarkers that are easily available in everyday practice and understandable to clinicians who adjust treatments should especially be preferred. In fact, in many of the most important clinical areas, user-friendly biomarkers are not available, probably as a consequence of the current momentum and enthusiasm for more complex markers.Facing the current situation and to boost translational epidemiology (1), this Special Issue presents a collection of observational studies providing real-world evidence of accessible-for-all risk factors with an interest to treat CKD patients specifically. Approximately 10 years ago, an interesting review contextualized the importance of observational evidence to reach a personalized treatment period for CKD . As an iReal-world  data constitutes a source of information to evaluate  diseases and patients affected by diseases. Large databases are now being performed to enlarge the knowledge on diseases and patients, and to facilitate physicians’ decisions. For instance, new risk factors for patients with coronavirus disease 2019 (COVID-19) and acute kidney function deterioration are proposed by our team, and such factors may be used as prognostic markers for this population to prevent bad outcomes . In addiSince several years, the amino acid metabolite profile was found to be related to CKD apparition. Indeed, the kidneys directly manage circulating levels of such molecules. However, not only kidney function decline may be predicted by amino acid levels and their ratios, but the characteristics of kidney affectation may be reflected by given profiles . For insThe intensity of inflammation and its consequences may in turn be measured. Oxidative stress, uremia, malnutrition and a high risk for cardiovascular events are expressions of the same common “magnum” alteration, which contribute to high CKD-associated mortality, as well as to morbidity charge as eGFR progressively deteriorates. Recently, there is an interest to better know the association between advanced glycation end-product (AGE) levels and soluble forms of the receptor for AGE (RAGE) with the pro-inflammatory state of patients with CKD. Particularly, this Special Issue highlights the inverse association between the cleave RAGE/endogenous secretory RAGE ratio with the risk of death in CKD patients . TherefoInterestingly, biomarkers must be looked for anywhere in CKD patients, i.e., all potential sources should be considered, and observations should not only be centered in metabolites. For instance, changes in gut microbiome composition towards a state of “intestinal dysbiosis”, contributing to a pro-inflammatory environment, should be searched in early CKD, especially in the cases of diabetic CKD or when a metabolic disease is suspected as the cause of CKD . Future Analyses leading to proposed biomarkers may be forced to consider composite outcomes , especially when using groups of markers are presumed to be more efficacious than using separately given biomarkers  . EspeciaNevertheless, observational evidence and especially that provided by real-world environments are limited importantly by confounders, among other biases such as attrition, selection and that related to information. It should not be forgotten that researchers on the “real-world”  are working outside rigorous research environments considering randomization to guarantee a more credible research production. In this context, sample size may oblige to repeat assessments in order to reproduce observations, and to make that then generalizable to the main population affected by CKD.Observational evidence is becoming an interesting way to propose biomarkers for persons affected by CKD, considering its diversity (heterogeneity) and the several conditions conducing to and maintaining kidney function loss and alterations associated to that. Examples of well-performing research are increasing in recent years, even if limitations in this type of evidence are criticizable when compared to more formal research dominated by randomization. The examples presented in this Special Issue aim to identify high-risk CKD and propose objectives targetable by future interventions.


Cognitive decline is an important contributor to disability in patients with chronic heart failure, affecting 25%–50% of patients. The aim of this review is to stress the importance of understanding pathophysiological mechanisms of heart failure involved in cognitive decline.An extensive PubMed search was conducted for the literature on the basic mechanisms of cerebral blood flow regulation, the effect of cardiac dysfunction on cerebral blood flow, and possible mechanisms underlying the association between cardiac dysfunction and cognitive decline.Published literature supports the thesis that cardiac dysfunction leads to cerebral blood flow impairment and predisposes to cognitive decline. One of the postulated mechanisms underlying cognitive decline in chronic heart failure is chronic regional hypoperfusion of critical brain areas. Cognitive function may be further compromised by microvascular damage due to cardiovascular risk factors. Furthermore, it is implied that cerebral blood flow assessment could enable early recognition of patients at risk and help guide appropriate therapeutic strategies.Interdisciplinary knowledge in the fields of neurology and cardiology is essential to clarify heart and brain interconnections in chronic heart failure. Understanding and identifying the basic neuropathophysiological changes in chronic heart failure could help with developing methods for early recognition of patients at risk, followed by institution of therapeutic actions to prevent or decrease cognitive decline. One of the postulated mechanisms underlying cognitive decline in chronic heart failure is chronic regional hypoperfusion of critical brain areas. Cognitive function may be further compromised by microvascular damage due to cardiovascular risk factors in chronic heart failure patients. Cerebral blood flow assessment is proposed for early recognition of patients at risk of cognitive decline and could guide further therapeutic strategy. On the other hand, intraparenchymal vessels are innervated by projections from subcortical neurons originating in locus coeruleus, nucleus basalis, and dorsal raphe nucleus Figure  Brassar.Sympathetic postganglionic nerve fibers originate mainly from the superior cervical ganglion, with noradrenaline, neuropeptide Y, and adenosine triphosphate as the main neurotransmitters , and nitric oxide synthase (NOS)  do not cross the blood–brain barrier (BBB) in the mature brain and therefore have minimal influence on the cerebral vasculature and cerebral metabolic rate , a condition frequently accompanying CHF, causes CBF disruption through specific mechanisms and will be dealt with separately. It carries a fivefold increased risk for thromboembolic transient ischemic attack and stroke (Gardarsdottir et al., 5In 1977, an article published in the Lancet proposed the name cardiogenic dementia for the CD observed following recurrent episodes of cardiac arrhythmias or heart disease (Dementia, 6Current guidelines suggest Mini–Mental Test and the Montreal Cognitive Test to evaluate cognitive function in CHF (Ponikowski et al., It is fair to assume that patients who are at risk of CD due to CHF could be identified through CBF evaluation even before neuropsychological testing reveals cognitive impairment. Various nuclear, magnetic resonance, and sonographic imaging methods have been used to evaluate CBF in CHF; (Caldas et al., 7The review of the contemporary literature supports the thesis that cardiac dysfunction leads to CBF impairment and predisposes to CD. It appears that the contributions to CBF impairment in such setting are multifactorial. An important role could be attributed to chronically activated neurohumoral mechanisms in CHF patients, including increased sympathetic activity, which is known to affect CBF predominantly in pathological conditions. With its vasoconstrictive effects, it could compromise CBF regulation and incline CHF patients to cerebral hypoperfusion. Microvascular damage due to cardiovascular risk factors in CHF patients could further potentiate CD in CHF. Areas with lack of collateral blood flow or increased density of perivascular sympathetic nerves, such as the medial temporal lobes and deep brain white matter, are predominantly prone to chronic global cerebral hypoperfusion. Therefore, injury in these critical brain regions is expected to be found in CHF patients, leading to CD. Understanding and identifying the basic neuropathophysiological changes involved could help with developing methods for early recognition of patients at risk, followed by institution of therapeutic actions to decrease CD in CHF patients.None to declare.All authors have made substantial contributions to the conception and design of the manuscript, acquisition of data, analysis and interpretation of data, drafting and critical revision of the article and have approved the final version to be submitted.https://publons.com/publon/10.1002/brb3.2176.The peer review history for this article is available at