Sex and gender disparities in the epidemiology and outcomes of chronic kidney disease

A lipidome landscape of aging in mice

Understanding the molecular mechanisms of aging is crucial for enhancing healthy longevity. We conducted untargeted lipidomics across 13 biological samples from mice at various life stages (2, 12, 19 and 24 months) to explore the potential link between aging and lipid metabolism, considering sex (male or female) and microbiome (specific pathogen-free or germ-free) dependencies. By analyzing 2,704 molecules from 109 lipid subclasses, we characterized common and tissue-specific lipidome alterations associated with aging. For example, the levels of bis(monoacylglycero)phosphate containing polyunsaturated fatty acids increased in various organs during aging, whereas the levels of other phospholipids containing saturated and monounsaturated fatty acids decreased. In addition, we discovered age-dependent sulfonolipid accumulation, absent in germ-free mice, correlating with Alistipes abundance determined by 16S ribosomal RNA gene amplicon sequencing. In the male kidney, glycolipids such as galactosylceramides, galabiosylceramides (Gal2Cer), trihexosylceramides (Hex3Cer), and mono- and digalactosyldiacylglycerols were detected, with two lipid classes-Gal2Cer and Hex3Cer-being significantly enriched in aged mice. Integrated analysis of the kidney transcriptome revealed uridine diphosphate galactosyltransferase 8A (UGT8a), alkylglycerone phosphate synthase and fatty acyl-coenzyme A reductase 1 as potential enzymes responsible for the male-specific glycolipid biosynthesis in vivo, which would be relevant to sex dependency in kidney diseases. Inhibiting UGT8 reduced the levels of these glycolipids and the expression of inflammatory cytokines in the kidney. Our study provides a valuable resource for clarifying potential links between lipid metabolism and aging.

8-OHdG mediates the association of co-exposure to fifty-five typical endocrine-disrupting chemicals with renal function: a cross-section investigation in Southern Chinese adults

Individual typical endocrine-disrupting chemicals (EDCs), including organophosphate triesters (OPEs), parabens, triclosan (TCS), bisphenols, benzophenones (BPs), phthalates (PAEs), and synthetic phenolic antioxidants (SPAs), are associated with renal dysfunction. However, the combined effects and underlying mechanisms of mixed EDC exposure on renal function remain unclear. Two hundred ninety-nine adult participants were enrolled in the cross-sectional survey conducted in Guangzhou, China. Urinary levels of 7 OPEs, 6 parabens, TCS, 14 bisphenols, 8 BPs, 15 PAEs, 4 SPAs, and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were determined, and estimated glomerular filtration rate (eGFR) was served as the outcome index. We found elevated levels of diphenyl phosphate (DPP), bisphenol A (BPA), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-butyl phthalate (MBP) showed dose-responsive associations with eGFR decline, However, nonlinear associations were observed for bis(2-butoxyethyl) hydrogen phosphate (BBOEP), TCS, 4-hydroxybenzophenone (HBP), mono-n-pentyl phthalate (MnPP), and mono-benzyl phthalate (MBzP). The quantile-based g-computation model demonstrated that a quartile increase in the EDC mixture corresponded to a 0.383-SD decrease (95% CI - 0.658 ~  - 0.108, P = 0.007) in eGFR. Notably, BPA was identified as the primary contributor to this effect. Moreover, 8-OHdG mediated the eGFR decline associated with EDC mixtures with a mediation proportion of 25.49%. A sex-modified effect was also observed (P = 0.004), indicating that exposure to the mixture of EDC was linked to more pronounced renal dysfunction in females. Our novel findings suggest that exposure to a typical mixture of EDCs is associated with renal dysfunction in the general adult population of Southern China. Furthermore, 8-OHdG may play a role in the pathogenesis of EDC mixture-related renal dysfunction.

Association between oxidative balance score in adults with and without chronic kidney disease: 2011-2028 NHANES

Introduction

Oxidative stress status is associated with CKD; however, few studies have investigated this association. The oxidative balance score (OBS) reflects systemic stress status and consists of 16 anti-and pro-oxidant dietary factors and four anti-and pro-oxidant lifestyle factors. Higher OBS implies exposure to more antioxidants. The purpose of this study was to explore the association between OBS and CKD.

Methods

We enrolled 8,134 study participants from the 2011-2018 National Health and Nutrition Examination Survey and obtained OBS by adding the 20 dietary and lifestyle factors. Based on OBS, the participants were divided into three groups. We performed logistic regression, subgroup analyzes, and restricted cubic spline regression to explore the association between OBS and CKD. In addition, we tested the adjusted model.

Results

OBS was negatively associated with CKD (OR: 0.54; 0.66, 0.82). After adjusting for all confounders, when dietary OBS was >20, the prevalence of CKD was reduced by 42% for each unit increase in OBS (p < 0.05). The negative associations of total OBS, dietary OBS, and lifestyle OBS with CKD were more significant in the female group. When the total OBS was ~20, the trend of decreasing prevalence in the female group was more significant.

Conclusion

OBS is negatively associated with chronic kidney disease.

Associations between long-term exposure to air pollution and kidney function utilizing electronic healthcare records: a cross-sectional study

BACKGROUND

Chronic kidney disease (CKD) affects more than 38 million people in the United States, predominantly those over 65 years of age. While CKD etiology is complex, recent research suggests associations with environmental exposures.

METHODS

Our primary objective is to examine creatinine-based estimated glomerular filtration rate (eGFRcr) and diagnosis of CKD and potential associations with fine particulate matter (PM2.5), ozone (O3), and nitrogen dioxide (NO2) using a random sample of North Carolina electronic healthcare records (EHRs) from 2004 to 2016. We estimated eGFRcr using the serum creatinine-based 2021 CKD-EPI equation. PM2.5 and NO2 data come from a hybrid model using 1 km2 grids and O3 data from 12 km2 CMAQ grids. Exposure concentrations were 1-year averages. We used linear mixed models to estimate eGFRcr per IQR increase of pollutants. We used multiple logistic regression to estimate associations between pollutants and first appearance of CKD. We adjusted for patient sex, race, age, comorbidities, temporality, and 2010 census block group variables.

RESULTS

We found 44,872 serum creatinine measurements among 7,722 patients. An IQR increase in PM2.5 was associated with a 1.63 mL/min/1.73m2 (95% CI: -1.96, -1.31) reduction in eGFRcr, with O3 and NO2 showing positive associations. There were 1,015 patients identified with CKD through e-phenotyping and ICD codes. None of the environmental exposures were positively associated with a first-time measure of eGFRcr < 60 mL/min/1.73m2. NO2 was inversely associated with a first-time diagnosis of CKD with aOR of 0.77 (95% CI: 0.66, 0.90).

CONCLUSIONS

One-year average PM2.5 was associated with reduced eGFRcr, while O3 and NO2 were inversely associated. Neither PM2.5 or O3 were associated with a first-time identification of CKD, NO2 was inversely associated. We recommend future research examining the relationship between air pollution and impaired renal function.

Gender and kidney transplantation

Kidney transplantation provides the best form of kidney replacement therapy with improvement in quality of life and longevity. However, disparity exists in its availability, utilisation and outcomes, not only due to donor availability or financial constraints but also arising from the influence of biological sex and its sociocultural attribute i.e., Gender. Women make up the majority of kidney donors but are less likely to be counselled regarding transpantation, be waitlisted or receive living/deceased donor kidney. Biological differences also contribute to differences in kidney transplantation among the sexes. Women are more likely to be sensitised owing to pregnancy, especially in multiparous individuals, complicating donor compatibility. A heightened immune system in women, evidenced by more autoimmune illnesses, increases the risk of allograft rejection and loss. Differences in the pharmacokinetics of transplant drugs owing to biological variances could also contribute to variability in outcomes. Transgender medicine is also increasingly becoming a relevant topic of study, providing greater challenges in the form of hormonal manipulations and anatomic changes. It is thus important to determine and study transplantation and its nuances in this backdrop to be able to provide relevant sex and gender-specific interventions and design better practices for optimum kidney transplant utilisation and outcomes.

Single-cell transcriptome atlas in C57BL/6 mice encodes morphological phenotypes in the aging kidneys

C57BL/6 mice are frequently utilized as murine models with the desired genetic background for altertion in multiple research contexts. So far, there is still a lack of comprehensive kidney morphology and single-cell transcriptome atlas at all stages of growth of C57BL/6 mice. To provide an interactive set of reference standards for the scientific community, we performed the current study to investigate the kidney's development throughout the capillary-loop stage until senescence. Eight groups, with five to six mice each, represented embryonic stage (embryos 18.5 days), suckling period (1 day after birth), juvenile stage (1 month old), adulthood (containing 3 months old, 6 months old and 10 months old), reproductive senescence stage (20 months old), and post-senescence stage (30 months old), respectively. With age, the thickness of the glomerular basement membrane (GBM) was increased. Notably, GBM knobs appeared at three months and became frequent with age. Using single-cell transcriptome data, we evaluated how various biological process appear in particular cell types and investigated the potential mechanism of formation of GBM konbs. In conclusion, having access to detailed kidney morphology and single-cell transcriptome maps from C57BL/6 mice at various developmental stages of C57BL/6 mice would be a novel and major resource for biological research and testing of prospective therapeutic approaches.

The Factors Influencing Chronic Kidney Disease Incidence: Database from the Korean National Health Insurance Sharing Service (NHISS)

Background: The global prevalence of chronic kidney disease (CKD) is increasing, with diabetes accounting for the highest proportion. We analyzed the influence of clinical factors on the incidence of CKD according to the renal function, primary focusing on patients with diabetes. Methods: We used the Sample Cohorts Database provided by the National Health Insurance Sharing Service (NHISS) in Korea. Participants aged ≥ 40 years who underwent a health checkup in 2009 were categorized into six groups based on their eGFR values (<60 mL/min, 60-89 mL/min, ≥90 mL/min) and the presence of diabetes. And all patients with CKD at 2009 screening were excluded. The participants were tracked from 2010 to 31 December 2019. The CKD incidence rate according to the eGFR values and the effect of the accompanying factors on CKD incidence were confirmed. Results: 148,089 people without CKD were analyzed. The CKD incidence rate was highest in those with eGFR < 60 mL/min with diabetes and lowest in those with eGFR ≥ 90 mL/min without diabetes. The CKD incidence rates were similar between the eGFR < 60 mL/min group without diabetes and the eGFR 60-89 mL/min group with diabetes. Compared to under 44 years of age, the hazard ratio of CKD incidence was 8 times higher in over 75 years of age. Men had a 1.7-fold higher risk of developing CKD than women. Current smoker, hypertension, dyslipidemia, myocardial infarction history, and atrial fibrillation and flutter increased the risk of CKD incidence. Age, diabetes, and baseline eGFR are important factors in the occurrence of CKD. As age increases, the risk of developing CKD in men increases compared to women. Conclusions: These results will be helpful in predicting risk groups for CKD and establishing strategies to lowering CKD incidence.

Higher potassium intake is associated with a lower risk of chronic kidney disease: population-based prospective study

BACKGROUND

High-potassium intake is associated with a lower risk of cardiovascular disease. However, the association between potassium intake and the development of chronic kidney disease (CKD) remains unclear.

OBJECTIVE

The objective of this study was to investigate whether potassium intake is associated with outcomes of incident CKD.

METHODS

This is a population-based prospective observational cohort study from the UK Biobank cohort between 2006 and 2010. We included 317,162 participants without CKD from the UK Biobank cohort. The main predictor was spot urine potassium-to-creatinine ratio (KCR). The primary outcome was incident CKD, which was defined by the International Classification of Disease 10 codes or Operating Procedure Codes Supplement 4 codes.

RESULTS

At baseline, individuals with higher KCR had lower blood pressure, body mass index, and inflammation, and were less likely to have diabetes and hypertension. During a median follow-up of 11.9 y, primary outcome events occurred in 15,246 (4.8%) participants. In the cause-specific model, the adjusted hazard ratio (aHR) per 1-standard deviation increase in KCR for incident CKD was 0.90 [95% confidence interval (CI): 0.89, 0.92]. Compared with quartile 1 of KCR, the aHRs (95% CIs) for quartiles 2-4 were 0.98 (0.94, 1.02), 0.90 (0.86, 0.95), and 0.80 (0.76, 0.84), respectively. In sensitivity analysis with different definitions of CKD, the results were similar. In addition, further analysis with dietary potassium intake also showed a negatively graded association with the primary outcome.

CONCLUSIONS

Higher urinary potassium excretion and intake were associated with a lower risk of incident CKD.

Investigation of the reasons for patients who choose peritoneal dialysis as kidney replacement therapies to change their decisions

INTRODUCTION

Peritoneal dialysis (PD) is one of the kidney replacement therapies (KRT). Patients' choice of KRT is influenced by personal causes, familial factors, factors related to healthcare professionals, and social factors.

METHODS

This study included 341 patients. PD patients who changed their KRT selection were asked for the reasons to change with a questionnaire.

RESULTS

Of the patients who initially chose PD, only 48.5% received KRT by PD. Five (20%) of the patients gave up PD compulsorily because they heard that the risk of infection with PD was higher, eight (40%) thought they could not do it, four (20%) because they needed to do assisted PD but had no relatives to do it, and three (15%) because they had abdominal surgery.

CONCLUSION

We believe that the fact that KRT training is carried out by a PD trained team and that patients are provided with assistance for PD will be effective in addressing the concerns of patients with PD undecided.

Relationships, race/ethnicity, gender, age, and living kidney donation evaluation willingness

Racial/ethnic and gender disparities in living donor kidney transplantation are large and persistent but incompletely explained. One previously unexplored potential contributor to these disparities is differential willingness to donate to recipients in specific relationships such as children, parents, and friends. We collected and analyzed data from an online sample featuring an experimental vignette in which respondents were asked to rate their willingness to donate to a randomly chosen member of their family or social network. Results show very large differences in respondents' willingness to donate to recipients with different relationships to them, favoring children, spouses/partners, siblings, and parents, and disfavoring friends, aunts/uncles, and coworkers. Evidence suggesting an interactive effect between relationship, respondent race/ethnicity, respondent or recipient gender, was limited to a few cases. At the p < 0.05 level, the parent-recipient gender interaction was statistically significant, favoring mothers over fathers, as was other/multiracial respondents' greater willingness to donate to friends compared to Whites. Additionally, other interactions were significant at the p < 0.10 level, such as Hispanics' and women's higher willingness to donate to parents compared to Whites and men respectively, women's lower willingness to donate to friends compared to men, and Blacks' greater willingness to donate to coworkers than Whites. We also examined differences by age and found that older respondents were less willing to donate to recipients other than their parents. Together these results suggest that differential willingness to donate by relationship group may be a moderately important factor in understanding racial/ethnic and gender disparities in living donor kidney transplantation.

Is There a Two-Way Risk between Decreased Testosterone Levels and the Progression and Prognosis of Chronic Kidney Disease? A Cohort Study Based on the National Health and Nutrition Examination Survey Database

PURPOSE

The causal relationship between the incidence and prognosis of chronic kidney disease (CKD) and serum testosterone levels in patients is not yet fully understood. This study aims to use the National Health and Nutrition Examination Survey (NHANES), a large-scale nationally representative sample, to investigate the relationship between CKD and testosterone.

MATERIALS AND METHODS

This study included six NHANES cycles for linear regression analysis, verified by multiple imputation methods. Stratified analysis and subgroup analysis were used to demonstrate the stability of CKD's effect on testosterone. Furthermore, we used Kaplan-Meier plots and log-rank tests to evaluate differences in survival rates between CKD male patients with low and normal levels of testosterone.

RESULTS

From a total of 71,163 subjects, the cohort selected 28,663 eligible participants. Results showed that CKD patients had testosterone levels 28.423 ng/mL (24.762, 32.083) lower than non-CKD patients. The results of multiple imputations (β=27.700, 95% confidence interval: 23.427, 31.974) were consistent with those of linear regression analysis, and the numerical match was good. Stratified regression analysis, and subgroup analysis results showed that CKD had a significant impact on testosterone at different dimensions. Kaplan-Meier plots showed significantly reduced survival rates in low testosterone CKD male patients (p<0.0001).

CONCLUSIONS

The results of this big data analysis suggest that there may be a two-way risk between low levels of testosterone and CKD. The testosterone levels of CKD patients were significantly lower than those of the non-CKD population, and CKD patients with low testosterone levels had poorer prognoses. These results suggest that correcting testosterone levels in a timely manner can have preventive and therapeutic effects on the progression of CKD.

Relationship of microvascular complications and healthy lifestyle with all-cause and cardiovascular mortality in women compared with men with type 2 diabetes

BACKGROUND

Sex differences exist in the prevalence of microvascular disease (MVD) and healthy-lifestyle adherence. Whether MVD and healthy lifestyles are associated with mortality risk similarly for women and men who have type 2 diabetes mellitus (T2DM) remains unknown.

METHODS

The present study included 9992 women and 15,860 men with T2DM from the UK Biobank. MVDs included retinopathy, peripheral neuropathy, and chronic kidney disease. Healthy lifestyle factors consisted of ideal BMI, nonsmoking, healthy diet, regular exercise, and appropriate sleep duration. Sex-specific hazard ratios (HRs) of mortality associated with the MVDs or healthy lifestyles were calculated and women-to-men ratio of HRs (RHR) were further estimated, after multivariable adjustment for potential confounders.

RESULTS

During a median of 12.7 years of follow-up, 4346 (1202 in women) all-cause and 1207 (254 in women) CVD deaths were recorded. The adjusted HRs (95% CI) of all-cause mortality for 1 additional increment of the MVDs were 1.71 (1.55, 1.88) for women and 1.48 (1.39, 1.57) for men, with an RHR of 1.16 (1.03, 1.30). The corresponding RHR was 1.36 (1.09, 1.69) for cardiovascular mortality. Adhering to a healthy lifestyle (≥4 vs. ≤1 lifestyle factor) was associated with an approximately 60%-70% lower risk of all-cause and cardiovascular mortality without sex differences (P-interaction >0.70). Furthermore, as compared with having no MVD and an unfavorable lifestyle, having ≥2 MVDs but a favorable lifestyle was not associated with a higher risk of all-cause mortality either in women (HR = 0.88; 95% CI: 0.49, 1.60) or in men (HR = 0.95; 95% CI: 0.64, 1.40), similarly when considering cardiovascular mortality.

CONCLUSIONS

In T2DM, while MVDs are more strongly associated with mortality risk in women than in men, adhering to a favorable lifestyle is associated with a substantially lower risk of mortality and may eliminate the detrimental impact of MVDs in both sexes.

Risk factors affecting the sleep quality of patients on dialysis: A single-center cross-sectional study

Sleep quality is among the common complication in patients on dialysis and serious affect their health and quality of life; however, other associated risk factors are unclear. This study aimed to investigate the risk factors affecting sleep quality in patients on dialysis. Data were collected from 260 patients who met the inclusion criteria at out hospital from May 2023 to October 2023. Questionnaires were completed by patients, and biochemical indicators were obtained from past medical records. Univariate and multifactor analyses were used to find factors influencing sleep quality in patients on dialysis. Simple linear regression results showed that female, type of kidney primary disease, high systolic blood pressure (SBP), pruritus, pruritus frequency, restless legs syndrome (RLS), anxiety, and depression were associated with poor sleep quality. Blood biochemical parameters showed that low sodium and calcium levels and high ferritin levels were associated with poor sleep quality. Multiple linear regression statistics showed that female, pruritus, RLS, high SBP, depression, and high ferritin levels were associated with poor sleep quality. This study showed that female, chronic nephritis syndrome, high SBP, pruritus, RLS, low mood. and high ferritin levels were associated with poor sleep quality. Future development of individual nursing and targeted therapies is key to improving sleep quality in patients on dialysis.

International comparison and time trends of first kidney transplant recipient characteristics across Europe: an ERA Registry study

BACKGROUND

The aim of this study was to provide an overview of age, sex and primary renal disease (PRD) distribution among first kidney transplant recipients across Europe.

METHOD

The European Renal Association (ERA) Registry database was used to obtain data on patients aged 20 years or older receiving their first kidney transplant between 2010 and 2019 from 12 European countries. The numbers and percentages of recipients in each age, sex and PRD group were calculated by country, donor type and year.

RESULTS

In total, 99 543 adults received a first kidney transplant. Overall, 23% of the recipients were 65 years or older, 36% were female, and 21% had glomerulonephritis and 15% diabetes mellitus as PRD. Compared with deceased donor kidney transplant recipients, living donor kidney transplant recipients were less often 65 years or older (13% versus 26%), more often had glomerulonephritis (25% versus 20%) and less often diabetes mellitus (8% versus 17%) as PRD. We found large international differences, which were most prominent for age and PRD and less prominent for sex. Over time, the largest change in recipient characteristics was observed for the percentage of recipients aged 65 years or older, increasing from 18% in 2010 to 28% in 2019 for all countries combined with a similar trend in most countries.

CONCLUSION

We observed large differences for age and PRD distribution between recipients of living and deceased donor kidneys and between European countries. Over time, the percentage of older first kidney transplant recipients increased.

K, C. G. S, Reddy GG. Gender disparity in maintenance hemodialysis units in South India: a cross-sectional observational study

Background

Diseases manifest differently according to gender in many medical specialties. However, sex differences in kidney diseases have not been well explored worldwide, especially in India. These differences could also be attributed to sociocultural factors. Although CKD is more prevalent in women worldwide, most men are initiated on kidney replacement therapy (KRT). This study aimed to examine sex disparities in patients on maintenance hemodialysis.

Materials and methods

A cross-sectional observational study was conducted in two maintenance hemodialysis units at the Institute of Nephrourology, a tertiary care referral government center in Bengaluru, India. Demographic characteristics and laboratory parameters were also recorded.

Results

In total, 374 adult patients (aged >18 years) were included in the study. Most patients (72.7%) were men. Mean age in men was 46.95 ± 12.65 years, and women was 46.63 ± 13.66 years. There was no significant difference in marital status and the availability of caretakers between the groups. Spouses were the predominant caretakers for both sexes (64% men and 51% women, P = 0.14). Sons cared more for patients with mother than fathers (19.6% vs 8.8%, P = 0.074). Diabetic nephropathy was the most common cause of ESKD in both groups (33.1% vs 31.3%, P = 0.92). Men had a significantly longer duration of HTN and received more HD sessions per week than women. Mean hemoglobin (9.9 ± 1.79 vs 9.46 ± 1.47 g%) and mean serum creatinine (7.76 ± 2.65 vs 6.41 ± 2.27 mg/dl) were higher in men compared to women (P <0.002). Intradialytic complications, such as hypotension and cramps, were significantly more common in women than in men (P = 0.004). Most men (47.1%) were planning a kidney transplant (and were waitlisted) compared with fewer women (43%). There was no significant difference in the average number of hospitalizations per month or HD vintage.

Conclusion

Women tend to initiate dialysis later, and a lesser number are waitlisted for kidney transplantation, which might be partly related to varying access to or delivery of health care services. Factors such as lack of education, insufficient identification of and strategies to address cultural obstacles to healthcare, and a shortage of financial means to afford medical care are potentially correctable elements that might explain this discrepancy.

Interaction between anemia and hyperuricemia in the risk of all-cause mortality in patients with chronic kidney disease

Aim

Both hyperuricemia and anemia are not only the manifestation of chronic kidney disease (CKD) but also related to its occurrence and development. A recent study has found that there was a synergetic effect between hyperuricemia and anemia on new-onset CKD. Herein we aimed to explore the roles of hyperuricemia and anemia in the all-cause mortality in patients with CKD.

Methods

Data of adult patients with CKD were extracted from the National Health and Nutrition Examination Surveys (NHANES) database in 2009-2018 in this retrospective cohort study. Weighted univariate and multivariate COX regression analyses were used to investigate the associations of hyperuricemia and anemia with all-cause mortality, and the evaluation indexes were hazard ratios (HRs) and 95% confidence intervals (CIs). The interaction effect between hyperuricemia and anemia on the risk of all-cause mortality was assessed via relative excess risk due to interaction (RERI) and attributable proportion of interaction (AP). Subgroup analyses of age, gender, CVD, hypertension, DM, and cancer were also performed to assess this interaction effect.

Results

Among 3,678 eligible patients, 819 died from all causes. After adjusting for covariables, we found that CKD patients with anemia (HR = 1.72, 95%CI: 1.42-2.09) or hyperuricemia (HR = 1.21, 95%CI: 1.01-11.45) had a higher risk of all-cause mortality. There was a potential synergetic effect between anemia and hyperuricemia on all-cause mortality, with RERI of 0.630 and AP of 0.291. Moreover, this synergetic effect was also observed in ≥65 years old (AP = 0.330), male (AP = 0.355), hypertension (AP = 0.736), non-hypertension (AP = 0.281), DM (AP = 0.371), and cancer (AP = 0.391) subgroups.

Conclusion

A potential synergetic effect between anemia and hyperuricemia on all-cause mortality was found in patients with CKD. However, further studies are needed to clarify the causal relationship between them.

The Heterogeneity of Symptom Burden and Fear of Progression Among Kidney Transplant Recipients: A Latent Class Analysis

Purpose

Kidney transplant recipients (KTRs) may experience symptoms that increase their fear of progression (FoP), but a dearth of research examines the issue from a patient-centered perspective. Our study aimed to first determine the category of symptom burden, then to explore the differences in characteristics of patients in different subgroups, and finally to analyze the impact of symptom subgroup on FoP.

Patients and Methods

Sociodemographic and Clinical Characteristics, Symptom Experience Scale, and Fear of Progression Questionnaire-Short Form were used. Latent class analysis was used to group KTRs according to the occurrence of symptoms. We used multivariate logistic regression to analyze the predictors of different subgroups. The differences in FoP among symptom burden subgroups were analyzed by hierarchical multiple regression.

Results

Three subgroups were identified, designated all-high (20.5%), moderate (39.9%), and all-low (39.6%) according to their symptom occurrence. Multivariate logistic regression showed that gender, post-transplant time, per capita monthly income, and hyperuricemia were the factors that distinguished and predicted the all-high subgroup (P < 0.05). Hierarchical multiple regression showed that symptom burden had a significant effect on FoP (class1 vs class3: β = 0.327, P < 0.001; class2 vs class3: β = 0.104, P = 0.046), explaining the 8.0% variance of FoP (ΔR2 = 0.080).

Conclusion

KTRs generally experience moderate or low symptom burden, and symptom burden is an influencing factor in FoP. Identifying the traits of KTRs with high symptom burden can help clinicians develop targeted management strategies and ease FoP of KTRs.

Sex disparities in mortality and cardiovascular outcomes in chronic kidney disease

Sex (biologically determined) and gender (socially constructed) modulate manifestations and prognosis of a vast number of diseases, including cardiovascular disease (CVD) and chronic kidney disease (CKD). CVD remains the leading cause of death in CKD patients. Population-based studies indicate that women present a higher prevalence of CKD and experience less CVD than men in all CKD stages, although this is not as clear in patients on dialysis or transplantation. When compared to the general population of the same sex, CKD has a more negative impact on women on kidney replacement therapy. European women on dialysis or recipients of kidney transplants have life expectancy up to 44.8 and 19.8 years lower, respectively, than their counterparts of similar age in the general population. For men, these figures stand at 37.1 and 16.5 years, representing a 21% to 20% difference, respectively. Hormonal, genetic, societal, and cultural influences may contribute to these sex-based disparities. To gain a more comprehensive understanding of these differences and their implications for patient care, well-designed clinical trials that involve a larger representation of women and focus on sex-related variables are urgently needed. This narrative review emphasizes the importance of acknowledging the epidemiology and prognosis of sex disparities in CVD among CKD patients. Such insights can guide research into the underlying pathophysiological mechanisms, leading to optimized treatment strategies and ultimately, improved clinical outcomes.

Analysis of risk factors for fatal renal complications after allogeneic hematopoietic cell transplantation

Various complications can influence hematopoietic cell transplantation (HCT) outcomes. Renal complications can occur during the early to late phases of HCT along with various factors. However, studies focusing on fatal renal complications (FRCs) are scarce. Herein, we analyzed 36,596 first allogeneic HCT recipients retrospectively. Overall, 782 patients died of FRCs at a median of 108 (range, 0-3,440) days after HCT. The cumulative incidence of FRCs was 1.7% and 2.2% at one and five years, respectively. FRCs were associated with older age, male sex, non-complete remission (non-CR), lower performance status (PS), and HCT comorbidity index (HCT-CI) associated with renal comorbidity in multivariate analysis. The risk factors within 100 days included older age, multiple myeloma, PS, and HCT-CI comorbidities (psychiatric disturbance, hepatic disease, obesity, and renal disease). Older age and male sex were risk factors between 100 days and one year. After one year, HCT-CI was associated with the presence of diabetes and prior solid tumor; total body irradiation was identified as a risk factor. Non-CR was a common risk factor in all three phases. Furthermore, acute and chronic graft-versus-host disease, reactivation of cytomegalovirus, and relapse of underlying disease also affected FRCs. Systematic follow-up may be necessary based on the patients' risk factors and post-HCT events.

A high level of thyroid-stimulating hormone is a risk factor for the development of chronic kidney disease in men: a 10-year cohort study

Hypothyroidism has been reported to be associated with chronic kidney disease (CKD). However, the impact of thyroid-stimulating hormone (TSH) on new onset of CKD and its gender dependence remain undetermined. We investigated the association of serum TSH level and the development of CKD defined by estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 or positive for urine protein in 28,990 Japanese subjects who received annual health examinations. After excluding subjects with no data for serum TSH, urinalysis and eGFR and those with CKD at baseline, a total of 10,392 subjects (men/women: 6802/3590, mean age: 48 years) were recruited. During a 10-year follow-up, 1185 men (6.7%) and 578 women (2.9%) newly developed CKD. Multivariable Cox proportional hazard models after adjustment of age, body mass index, smoking habit, hypertension, diabetes mellitus, dyslipidemia, ischemic heart disease and eGFR (≥ 90 mL/min/1.73 m2) showed that the hazard ratio (HR) for the development of CKD in the high TSH (> 4.2 mU/L) group was significantly higher than that in the low TSH (≤ 4.2 mU/L) group in men (HR [95% confidence interval]: 1.41 [1.09-1.83]) but not in women (1.08 [0.77-1.51]). There was a significant interaction between sex and the category of TSH level for the development of CKD (p = 0.02). The adjusted HR with a restricted cubic spline increased with a higher level of TSH in men but not in women. In conclusion, a high level of TSH is associated with an increased risk for the development of CKD in men but not in women.

Sex-specific differences in a large cohort of Brazilian incident dialysis patients over 12 years: A retrospective study

OBJECTIVE

Sex-specific differences in the epidemiology of chronic kidney disease, such as higher prevalence of women on pre-dialysis and men on chronic dialysis treatment, have been reported worldwide. In this regard, data from non-high-income countries are scarce. We aimed to compare the demographic, clinical, and dialysis characteristics of incident dialysis patients, both men and women, in a large cohort of Brazilian patients over a 12-year period.

METHODS

This was a multicentric retrospective cohort study coordinated by the Brazilian Society of Nephrology. The study included all adult incident dialysis patients in the Brazilian Dialysis Registry from January 2011 to December 2022. The variables studied encompassed age, skin color, education, CKD etiology, predialysis nephrologist care, dialysis characteristics, and geographic region. Additionally, the sample was analyzed for each of the three 4-year periods over the 12 years of data collection.

RESULTS

A total of 24,632 incident dialysis patients were included. Men were 59.1% of the dialysis population, remaining stable over the three 4-year periods. Besides other differences, women started dialysis younger (58.5 ± 16.2 years vs 59.5 ± 14.4 years; p < 0.001), had a lower educational level (less than 8 years at school: 54% vs 44%; p < 0.001), received more predialysis nephrologist care (46.2% vs 44.2%; p = 0.04), and had a higher prevalence of peritoneal dialysis (4.4% vs 3.5%; p = 0.03).

CONCLUSION

We consistently observed a higher prevalence of men on dialysis and differences in demographic, clinical, and dialysis characteristics. The underlying reasons for these sex differences still necessitate further clarification.

Multiple urinary peptides display distinct sex-specific distribution

Previous studies have established the association of sex with gene and protein expression. This study investigated the association of sex with the abundance of endogenous urinary peptides, using capillary electrophoresis-coupled to mass spectrometry (CE-MS) datasets from 2008 healthy individuals and patients with type II diabetes, divided in one discovery and two validation cohorts. Statistical analysis using the Mann-Whitney test, adjusted for multiple testing, revealed 143 sex-associated peptides in the discovery cohort. Of these, 90 peptides were associated with sex in at least one of the validation cohorts and showed agreement in their regulation trends across all cohorts. The 90 sex-associated peptides were fragments of 29 parental proteins. Comparison with previously published transcriptomics data demonstrated that the genes encoding 16 of these parental proteins had sex-biased expression. The 143 sex-associated peptides were combined into a support vector machine-based classifier that could discriminate males from females in two independent sets of healthy individuals and patients with type II diabetes, with an AUC of 89% and 81%, respectively. Collectively, the urinary peptidome contains multiple sex-associated differences, which may enable a better understanding of sex-biased molecular mechanisms and the development of more accurate diagnostic, prognostic, or predictive classifiers for each individual sex.

Advancing Healthcare Equity in Nephrology: Addressing Racial and Ethnic Disparities in Research Trials and Treatment Strategies

Within the healthcare sector, especially in the field of nephrology, the matter of gender and racial inequalities continues to be a critical concern that requires immediate focus. Women, particularly those of underrepresented racial groups, face significant challenges due to a lack of representation in research studies, leading to a deficit in knowledge about how kidney diseases affect them differently. These challenges are exacerbated by systemic biases in the healthcare system, which manifest in both gender and racial dimensions, hindering access to and the quality of care for kidney diseases. Addressing these complex disparities requires a recalibration of risk stratification models to include both gender- and race-specific factors and a transformation of healthcare policies to facilitate a more inclusive and sensitive approach. Essential to this transformation is the empowerment of women of all races to actively participate in their healthcare decisions and the strengthening of support systems to help them navigate the complexities of the healthcare environment. Furthermore, education programs must be designed to be culturally competent and address the unique needs and concerns of women across different racial backgrounds. Promoting a collaborative patient-provider relationship is crucial in fostering an environment where equity, dignity, and respect are at the forefront. The path to equitable nephrology care lies in a concerted, collective action from researchers, healthcare providers, policymakers, and patients, ensuring that every individual receives the highest standard of care, irrespective of gender or race.

Gender disparities in kidney replacement therapies and transplantation in Colombia

BACKGROUND

In chronic kidney disease (CKD), there are historical inequities in multiple stages of the pathway for organ transplantation. Women have been recognized as disadvantaged within this process even after several efforts. Therefore, we aimed to analyze the prevalence and incidence of CKD by gender and their access to Kidney replacement therapy (KRT) in Colombia.

METHODS

A cross-sectional study based on secondary analysis of national information on CKD, hypertension, diabetes, waiting list, deceased, and living donor transplantation between 2015 and 2020.

RESULTS

In Colombia, 4.934.914 patients were diagnosed with hypertension, diabetes, or CKD. 60,64% were female, with a mean age of 63.84 years (SD 14,36). Crude incidence for hypertension (10.85 vs. 7.21 /1000 inhabitants), diabetes mellitus (3.77 vs. 2.98 /1000 inhabitants), and CKD (4 vs. 2 /1000 inhabitants) was higher for females. Crude incidence for KRT was 86.45 cases /100.0000 inhabitants. In 2020, 2978 patients were on the waiting list, 44% female. There were 251 deaths on the waiting list, 38% female. This year, 517 kidney transplants were performed, and only 40% were female.

CONCLUSION

In Colombia, there are proportionally more females with CKD and precursor comorbidities. Nevertheless, there are fewer females on the waiting list and transplanted annually.

Prevalence of chronic kidney disease in Tunisian diabetics: the TUN-CKDD survey

BACKGROUND

In Tunisia, the prevalence of diabetes mellitus increased from 15.5% on 2016 to 23% by 2023. While Chronic Kidney Disease (CKD) stills the most dreaded complications of diabetes, studies on the prevalence of chronic kidney disease non-dialysis diet are scarce. The aim of this study was to assess the prevalence of chronic kidney disease among the Tunisian diabetic population based on investigators' specialty, demographic criteria (gender, age, duration of diabetes and geographic distribution) and diagnosis criteria (albuminuria and/or eGFR).

METHODS

This observational, multicentric, and cross-sectional study enrolled all diabetic subjects from all regions of Tunisia with at least 3 months of follow-up before the inclusion date, from 09 January to 08 February 2023. CKD diagnosis was established based on the KDIGO guidelines. The study was carried out at medical departments and ambulatory clinics of different healthcare providers. Baseline data were collected by investigators using an electronic case report form (eCRF). Continuous variables were described by means, median, standard deviation, and quartiles. Categorical data were tabulated in frequencies and percentages.

RESULTS

The overall prevalence of CKD among the 10,145 enrolled patients with diabetes mellitus was 38.7% with a 95%CI [37.8-39.6%]. 50.9% were male, with a mean age of 67.5 (± 11.3) years. The mean diabetes duration was 16.1 years (± 8.9). The highest CKD prevalence was noted among nephrologists (82.2%), while it was similar between the cardiologists and the primary care physicians (30.0%). CKD prevalence was highest among males (43.0% versus 35.1%) and increased proportionally with patients' age and diabetes duration. CKD was more frequent in the Mid-East Area when compared to other regions (49.9% versus 25.3 to 40.1% in other regions). Albuminuria was present within 6.6% of subjects with CKD, and it was found an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m² within 13.3% of subjects wit h CKD. 18.9% had both criteria.

CONCLUSIONS

In Tunisia, CKD among diabetics had a prevalence of 38.7%, approaching European prevalence. The prevalence discrepancy worldwide of CKD can be improved with a larger population size and by implementing standardized practices.

Characteristics of Vascular Access Cannulation Complications in End Stage Kidney Disease Patients in West Java from 2018 to 2022: A Retrospective Observational Study

Background

End-stage kidney disease (ESKD) is associated with a tremendous financial burden. Data in Indonesia shows an increasing number of patients with ESKD taking hemodialysis as a routine procedure every year. Establishment and maintenance of vascular access are important in the management of ESKD. Vascular complications that often arise due to hemodialysis are common and one of the main reasons for hospitalization. Cannulation complications ranged from minor hematomas to acute bleeding from pseudoaneurysms that required emergency surgical procedures. This study aims to assess the different clinicopathological characteristics of ESKD patients with vascular access cannulation complications and the surgical management related to the complications.

Materials and Methods

This research is a retrospective observational study. The research subjects in this study were ESKD patients in the vascular and endovascular surgery division of the tertiary hospital in West Java, Indonesia. There were 121 study subjects. Clinicopathological characteristics of vascular cannulation complications and surgical management are extracted from the medical record.

Results

Three major vascular complications were ruptured pseudoaneurysms 64/121 (52.9%), impending rupture pseudoaneurysms 28/121 (23.1%), and pseudoaneurysms 21/121 (17.4%). Common surgical procedures were ligation of the draining vein 47/121 (38.8%), arterial primary repair 28/121 (23.1%), and arterial patch repair 18/121 (14.9%). There was a significant relationship between symptoms of bleeding in ruptured pseudoaneurysms and bulging masses in pseudoaneurysms (p = 0.001). There was a significant relationship between the diameter of the vascular mass, vascular defect size, and hematoma and the type of surgical procedure taken (p < 0.010).

Conclusion

Ruptured, impending rupture, and pseudoaneurysms are major complications of vascular access in ESKD patients, and there was a significant relationship between the carried-out surgical procedure and the size of the vascular mass, defect, and hematoma.

Brazil Nut-Enriched Diet Modulates Enteric Glial Cells and Gut Microbiota in an Experimental Model of Chronic Kidney Disease

Introduction: Chronic kidney disease (CKD) promotes gut dysbiosis, and enteric glial reactivity, a feature of intestinal inflammation. Brazil nut modulated enteric glial profile in healthy animals and could modulate these cells in 5/6 nephrectomized rats.Methods: A 5/6 nephrectomy-induced CKD and Sham-operated rats were divided as follows: CKD and Sham received a standard diet and CKD-BN and Sham-BN received a 5% Brazil nut enriched-diet. The protein content of glial fibrillary acid protein (GFAP), enteric glial marker, and GPx protein content and activity were assessed in the colon. The major phyla of gut microbiota were assessed.Results: CKD-BN group presented a decrease in GFAP content (p = 0.0001). The CKD-BN group modulated the abundance of Firmicutes, increasing its proportion compared to the CKD group. The CKD-BN group showed increased GPx activity in the colon (p = 0.0192), despite no significant difference in protein content.Conclusion: Brazil nut-enriched diet consumption decreased enteric glial reactivity and modulated gut microbiota in the CKD experimental model.

Risk factors associated with glomerular filtration rate in Mexican adults with type 2 diabetes mellitus

INTRODUCTION

Type 2 diabetes mellitus (T2DM) is related to glomerular filtration rate (GFR) impairment, which is one of the main causes of chronic kidney disease. The objective of this study was to identify the risk factors related to GFR in Mexican adults with T2DM, using a validated multiple linear regression model (MLRM), with emphasis in body adiposity, glycemic control, duration of the diabetes and other relevant risk factors.

MATERIALS AND METHODS

A cross-sectional, analytical, and observational study was carried out in 252 adults with a previous diagnosis of T2DM. Body mass index (BMI) and waist circumference (WC) were determined and a fasting blood sample was collected for glucose, creatinine and HbA1c determinations. GFR was calculated with the Cockcroft-Gault equation adjusted for body surface area. Four MLRM were performed to determine the factors related to the GFR; it was evaluated whether these models complied with the statistical assumptions of the linear regression model.

RESULTS

The average age of the participants was 60 ± 12 years, 62.3% of them were women. GFR correlated with BMI and WC; age and duration of the diabetes were associated inversely. Model 4 of the MLRM reported a coefficient of determination of 53.5% where the variables BMI (β = 1.31), male sex (β = -6.01), duration of T2DM (β = -0.57), arterial hypertension (β = -6.53) and age (β = -1.45) were simultaneously and significantly related to the GFR.

CONCLUSIONS

Older age, male sex, longer duration of T2DM and the presence of arterial hypertension were associated with a decrease in the GFR; BMI and WC were directly associated. No effect of glucose and HbA1c on GFR was observed.

Comprehensive analysis of the gene expression profile of the male and female BTBR mice with diabetic nephropathy

Comprehensive insight into the gender-based gene expression-related omics data in a rodent model of diabetic nephropathy (DN) is scarce. In the present study, the gender-based genes regulating different pathways involved in the progression of DN were explored through an unbiased RNA sequence of kidneys from BTBR mice with DN. We identified 17,739 and 17,981 genes in male and female DN mice; 1121 and 655 genes were expressed differentially (DEGs, differentially expressed genes) in male and female DN mice; both genders displayed only 195 DEGs. In the male DN mice, the number of upregulated genes was nearly the same as that of the down-regulated genes. In contrast, the number of upregulated genes was lesser than that of the down-regulated genes in the female DN mice, manifesting a remarkable gender disparity during the progression of DN in this animal model. Gene Ontology (GO) and KEGG-enriched results showed that most of these DEGs were related to the critical biological processes, including metabolic pathways, natural oxidation, bile secretion, and PPAR signaling; all are highly associated with DN. Notably, the DEGs significantly enriched for steroid hormone biosynthesis pathway were identified in both genders; the number of DEGs increased was 22 in male DN mice and 14 in female DN mice. Specifically, the Ugt1a10, Akr1c12, and Akr1c14 were upregulated in both genders. Interestingly, the Hsd11b1 gene was upregulated in female DN mice but downregulated in male DN mice. These results suggest that a significant gender-based variance in the gene expression occurs during the progression of DN and may be playing a role in the advancement of DN in the BTBR mouse model.

Renal function and periprocedural complications in patients undergoing left atrial catheter ablation: A comparison between uninterrupted direct oral anticoagulants and phenprocoumon administration

BACKGROUND

Data regarding uninterrupted oral anticoagulation in patients with chronic kidney disease (CKD) during catheter ablation for left atrial arrhythmias is limited. This study aimed to evaluate the safety and efficacy of periprocedural uninterrupted direct oral anticoagulants (DOAC) compared with uninterrupted phenprocoumon in patients with CKD undergoing left atrial catheter ablation.

METHODS AND RESULTS

We conducted a retrospective single-center study of patients who underwent left atrial catheter ablation between 2016 and 2019 with underlying chronic kidney disease (glomerular filtration rate (GFR) between 15 and 45 ml/min). The primary objective of this study was to investigate whether direct oral anticoagulant (DOAC) therapy or warfarin presents a superior safety profile in patients with chronic kidney disease (CKD) undergoing left atrial catheter ablation. We compared periprocedural complications (arteriovenous fistula, aneurysm, significant hematoma (> 5 cm)) and/or bleeding (drop in hemoglobin of >2 g/dl, pericardial effusion, retroperitoneal bleeding, other bleeding, stroke) between patients receiving either uninterrupted DOAC or warfarin therapy. Secondary analysis included patient baseline characteristics as well as procedural data. A total of 188 patients (female n = 108 (57%), mean age 75.3 ± 8.1 years, mean GFR 36.8 ± 6 ml/min) were included in this study. Underlying arrhythmias were atrial fibrillation (n = 104, 55.3%) and atypical atrial flutter (n = 84, 44.7%). Of these, n = 132 patients (70%) were under a DOAC medication, and n = 56 (30%) were under phenprocoumon. Major groin complications including pseudoaneurysm and/or AV fistula occurred in 8.9% of patients in the phenprocoumon group vs. 11.3% of patients in the DOAC group, which was not statistically significant (p = 0.62). Incidence of cardiac tamponade (2.3% vs. 0%; p = 0.55) and stroke (0% vs. 0%) were low in both DOAC and phenprocoumon groups with similar post-procedural drops in hemoglobin levels (1.1±1 g/dl vs 1.1±0.9 g/dl; p = 0.71).

CONCLUSION

The type of anticoagulation had no significant influence on bleeding or thromboembolic events as well as groin complications in this retrospective study. Despite observing an increased rate of groin complications, the uninterrupted use of DOAC or phenprocoumon during left atrial catheter ablation in patients with CKD appears to be feasible and effective.

Physical and psychosocial burden experienced by women on maintenance hemodialysis

BACKGROUND

The global prevalence of chronic kidney disease is growing at an alarming rate, and the number of patients progressing to kidney failure is increasing. A substantial number of patients are undergoing hemodialysis (HD), which improves health and lengthens life. However, it imposes multiple physical and psychological demands on the patients. With the intensity of symptoms being greater among women, a greater focus is needed to obtain empirical evidence regarding the health problems of females receiving HD.

MATERIALS AND METHODS

A descriptive qualitative design was used to explore the health problems of women undergoing maintenance HD. The sampling technique used was maximum variation purposive sampling. The data were collected through in-depth face-to-face interviews with 12 female patients attending the dialysis unit of a tertiary care hospital in northern Kerala, South India, using a semi-structured interview guide. The interview was audiotaped, and the participant content was later converted verbatim into English. The content was imported to NVivo and coded. Thematic analysis was performed using Braun and Clarke's six-step approach.

RESULT

During data analysis, six major themes and 20 subthemes emerged. The themes include (1) physical suffering, (2) mental agony, (3) restricted life, (4) sexual inactivity, (5) breakdown of social life, and (6) financial hardship.

CONCLUSION

Females undergoing maintenance hemodialysis experience significant health-related issues in all major dimensions of health. They are physically vulnerable, psychologically defeated, and socially detached. The study highlights the need for detailed evaluation and consistently supportive and educational care.

X-chromosome and kidney function: evidence from a multi-trait genetic analysis of 908,697 individuals reveals sex-specific and sex-differential findings in genes regulated by androgen response elements

X-chromosomal genetic variants are understudied but can yield valuable insights into sexually dimorphic human traits and diseases. We performed a sex-stratified cross-ancestry X-chromosome-wide association meta-analysis of seven kidney-related traits (n = 908,697), identifying 23 loci genome-wide significantly associated with two of the traits: 7 for uric acid and 16 for estimated glomerular filtration rate (eGFR), including four novel eGFR loci containing the functionally plausible prioritized genes ACSL4, CLDN2, TSPAN6 and the female-specific DRP2. Further, we identified five novel sex-interactions, comprising male-specific effects at FAM9B and AR/EDA2R, and three sex-differential findings with larger genetic effect sizes in males at DCAF12L1 and MST4 and larger effect sizes in females at HPRT1. All prioritized genes in loci showing significant sex-interactions were located next to androgen response elements (ARE). Five ARE genes showed sex-differential expressions. This study contributes new insights into sex-dimorphisms of kidney traits along with new prioritized gene targets for further molecular research.

Sociodemographic Disparities in Adults with Kidney Failure: A Meta-Analysis

This meta-analysis aims to assess current evidence regarding sociodemographic disparities among adults with kidney failure. Medline, Scopus, Web of Science, CENTRAL, and Google Scholar were systematically searched from inception to 20 February 2022. Overall, 165 cohort studies were included. Compared to White patients, dialysis survival was significantly better among Black (hazard ratio-HR: 0.68; 95% CI: 0.61-0.75), Asian (HR: 0.67; 95% CI: 0.61-0.72) and Hispanic patients (HR: 0.80; 95% CI: 0.73-0.88). Black individuals were associated with lower rates of successful arteriovenous fistula use, peritoneal dialysis and kidney transplantation, as well as with worse graft survival. Overall survival was significantly better in females after kidney transplantation compared to males (HR: 0.87; 95% CI: 0.84-0.90). Female sex was linked to higher rates of central venous catheter use and a lower probability of kidney transplantation. Indices of low SES were associated with higher mortality risk (HR: 1.22, 95% CI: 1.14-1.31), reduced rates of dialysis with an arteriovenous fistula, peritoneal dialysis and kidney transplantation, as well as higher graft failure risk. In conclusion, Black, Asian and Hispanic patients present better survival in dialysis, while Black, female and socially deprived patients demonstrate lower rates of successful arteriovenous fistula use and limited access to kidney transplantation. PROSPERO registration: CRD42022300839.

Circulating metabolites associated with kidney function decline and incident CKD: a multi-platform population-based study

Background

Investigation of circulating metabolites associated with kidney function and chronic kidney disease (CKD) risk could enhance our understanding of underlying pathways and identify new biomarkers for kidney function.

Methods

We selected participants from the population-based Rotterdam Study with data on circulating metabolites and estimated glomerular filtration rate based on serum creatinine (eGFRcreat) available at the same time point. Data on eGFR based on serum cystatin C (eGFRcys) and urine albumin-to-creatinine ratio (ACR) were also included. CKD was defined as eGFRcreat <60 ml/min per 1.73 m2. Data on circulating metabolites (ntotal = 1381) was obtained from the Nightingale and Metabolon platform. Linear regression, linear mixed, and Cox proportional-hazards regression analyses were conducted to study the associations between metabolites and kidney function. We performed bidirectional two-sample Mendelian randomization analyses to investigate causality of the identified associations.

Results

We included 3337 and 1540 participants with data from Nightingale and Metabolon, respectively. A total of 1381 metabolites (243 from Nightingale and 1138 from Metabolon) were included in the analyses. A large number of metabolites were significantly associated with eGFRcreat, eGFRcys, ACR, and CKD, including 16 metabolites that were associated with all four outcomes. Among these, C-glycosyltryptophan (HR 1.50, 95%CI 1.31;1.71) and X-12026 (HR 1.46, 95%CI 1.26;1.68) were most strongly associated with CKD risk. We revealed sex differences in the associations of 11-ketoetiocholanolone glucuronide and 11-beta-glucuronide with the kidney function assessments. No causal associations between the identified metabolites and kidney function were observed.

Conclusion

Our study indicates that several circulating metabolites are associated with kidney function which are likely to have potential as biomarkers, rather than as molecules involved in the pathophysiology of kidney function decline.

Differences in peripheral microcirculatory blood flow regulation in chronic kidney disease based on wavelet analysis of resting near-infrared spectroscopy

Vascular impairment is closely related to increased mortality in chronic kidney disease (CKD). The objective of this study was to assess impairments in the regulation of peripheral microvascular perfusion in patients with CKD based on time-frequency spectral analysis of resting near-infrared spectroscopy (NIRS) signals. Total hemoglobin (tHb) concentration and tissue saturation index (TSI) signals were collected using NIRS for a continuous 5 mins at 10 Hz from the forearm of 55 participants (34 CKD including 5 with end-stage renal disease, and 21 age-matched control). Continuous wavelet transform-based spectral analysis was used to quantify the spectral amplitude within five pre-defined frequency intervals (I, 0.0095-0.021 Hz; II, 0.021-0.052 Hz; III, 0.052-0.145 Hz; IV, 0.145-0.6 Hz and V, 0.6-2.0 Hz), representing endothelial, neurogenic, myogenic, respiratory and heartbeat activity, respectively. CKD patients showed lower tHb average spectral amplitude within the neurogenic frequency interval compared with controls (p = 0.014), consistent with an increased sympathetic outflow observed in CKD. CKD patients also showed lower TSI average spectral amplitude within the endothelial frequency interval compared with controls (p = 0.046), consistent with a reduced endothelial function in CKD. These findings demonstrate the potential of wavelet analysis of NIRS to provide complementary information on peripheral microvascular regulation in CKD.

Sex differences in renal transporters: assessment and functional consequences

Mammalian kidneys are specialized to maintain fluid and electrolyte homeostasis. The epithelial transport processes along the renal tubule that match output to input have long been the subject of experimental and theoretical study. However, emerging data have identified a new dimension of investigation: sex. Like most tissues, the structure and function of the kidney is regulated by sex hormones and chromosomes. Available data demonstrate sex differences in the abundance of kidney solute and electrolyte transporters, establishing that renal tubular organization and operation are distinctly different in females and males. Newer studies have provided insights into the physiological consequences of these sex differences. Computational simulations predict that sex differences in transporter abundance are likely driven to optimize reproduction, enabling adaptive responses to the nutritional requirements of serial pregnancies and lactation - normal life-cycle changes that challenge the ability of renal transporters to maintain fluid and electrolyte homeostasis. Later in life, females may also undergo menopause, which is associated with changes in disease risk. Although numerous knowledge gaps remain, ongoing studies will provide further insights into the sex-specific mechanisms of sodium, potassium, acid-base and volume physiology throughout the life cycle, which may lead to therapeutic opportunities.

Are Differences in Living Kidney Donation Rates a Sex or a Gender Disparity?

Sex-disaggregated data reveal significant disparities in living kidney donation, with more female than male living kidney donors in most countries and proportions over 60% in some countries. We summarize the present state of knowledge with respect to the potential drivers of this disparity and argue that it is primarily driven by gender-related factors. First, we present the differences between sex and gender and then proceed to summarize the potential medical reasons that have been proposed to explain why males are less likely to be living kidney donors than females, such as the higher prevalence of kidney failure in males. We then present counterarguments as to why biological sex differences are not enough to explain lower living kidney donation among males, such as a higher prevalence of chronic kidney disease among females, which could affect donation rates. We argue that gender differences likely provide a better explanation as to why there are more women than men living kidney donors and explore the role of economic and social factors, as well as gender roles and expectations, in affecting living kidney donation among both men and women. We conclude with the need for a gender analysis to explain this complex psychosocial phenomenon in living kidney donation.

Mechanisms and consequences of sex differences in immune responses

Biological sex differences refer to differences between males and females caused by the sex chromosome complement (that is, XY or XX), reproductive tissues (that is, the presence of testes or ovaries), and concentrations of sex steroids (that is, testosterone or oestrogens and progesterone). Although these sex differences are binary for most human individuals and mice, transgender individuals receiving hormone therapy, individuals with genetic syndromes (for example, Klinefelter and Turner syndromes) and people with disorders of sexual development reflect the diversity in sex-based biology. The broad distribution of sex steroid hormone receptors across diverse cell types and the differential expression of X-linked and autosomal genes means that sex is a biological variable that can affect the function of all physiological systems, including the immune system. Sex differences in immune cell function and immune responses to foreign and self antigens affect the development and outcome of diverse diseases and immune responses.

Differences in the epidemiology, management and outcomes of kidney disease in men and women

Improved understanding of differences in kidney disease epidemiology, management and outcomes in men and women could help nephrologists to better meet the needs of their patients from a sex- and gender-specific perspective. Evidence of sex differences in the risk and outcomes of acute kidney injury is mixed and dependent on aetiology. Women have a higher prevalence of chronic kidney disease (CKD) stages 3-5 than men, whereas men have a higher prevalence of albuminuria and hence CKD stages 1-2. Men show a faster decline in kidney function, progress more frequently to kidney failure and have higher mortality and risk of cardiovascular disease than women. However, the protective effect of female sex is reduced with CKD progression. Women are less likely than men to be aware of, screened for and diagnosed with CKD, started on antiproteinuric medication and referred to nephrologist care. They also consistently report a poorer health-related quality of life and a higher symptom burden than men. Women experience greater barriers than men to access the waiting list for kidney transplantation, particularly with respect to older age and obesity. However, women also have longer survival than men after transplantation, which may partly explain the comparable prevalence of transplantation between the sexes.

Self-controlled Case Series Study for Acute Kidney Injury after Starting Proton Pump Inhibitors or Potassium-Competitive Acid Blocker in Patients with Cancer Using a Large Claims Database

To investigate the risk of acute kidney injury (AKI) in patients with cancer following the initiation of proton pump inhibitors (PPIs) and potassium-competitive acid blocker (PCAB), considering sex and anti-cancer drug use. We conducted a self-controlled case-series study using the Japan Medical Data Center claims data from 12422 patients with cancer who were prescribed PPIs or PCAB between January 2017 and December 2019. Considering the timing of PPI or PCAB, control period (days -120 to -1), risk period 1 (days 0 to +30), and risk period 2 (days +31 to +365) were defined. To assess the incidence rate ratio (IRR) and 95% confidence interval (CI) as the risk ratio, we adjusted for anti-cancer drugs to assess the risk of AKI. Additionally, we also examined sex differences to identify the risk of AKI. AKI was observed in risk period 1 [2.05 (1.12-3.72), p = 0.0192], but a slight reduction was noted in risk period 2 [0.60 (0.36-1.00), p = 0.0481]. A sex-specific increase in the risk of AKI was observed only in males during risk period 1 [2.18 (1.10-4.32), p = 0.0260], with a reduction in risk period 2 [0.48 (0.26-0.89), p = 0.0200]. We identified an increased risk of AKI in patients with cancer starting PPIs or PCAB particularly in males within 30 d after PPI or PCAB initiation, emphasizing the need for vigilant monitoring and management of AKI in this patient population.

Sex differences in the survival benefit of kidney transplantation: a retrospective cohort study using target trial emulation

BACKGROUND

Kidney transplantation is the preferred treatment for eligible patients with kidney failure who need renal replacement therapy. However, it remains unclear whether the anticipated survival benefit from kidney transplantation is different for women and men.

METHODS

We included all dialysis patients recorded in the Austrian Dialysis and Transplant Registry who were waitlisted for their first kidney transplant between 2000 and 2018. In order to estimate the causal effect of kidney transplantation on 10-year restricted mean survival time, we mimicked a series of controlled clinical trials and applied inverse probability of treatment and censoring weighted sequential Cox models.

RESULTS

This study included 4408 patients (33% female) with a mean age of 52 years. Glomerulonephritis was the most common primary renal disease both in women (27%) and men (28%). Kidney transplantation led to a gain of 2.22 years (95% CI 1.88 to 2.49) compared with dialysis over a 10-year follow-up. The effect was smaller in women (1.95 years, 95% CI 1.38 to 2.41) than in men (2.35 years, 95% CI 1.92 to 2.70) due to a better survival on dialysis. Across ages the survival benefit of transplantation over a follow-up of 10 years was smaller in younger women and men and increased with age, showing a peak for both women and men aged about 60 years.

CONCLUSIONS

There were few differences in survival benefit by transplantation between females and males. Females had better survival than males on the waitlist receiving dialysis and similar survival to males after transplantation.

Associations Between Life's Essential 8 and Chronic Kidney Disease

BACKGROUND

Chronic kidney disease (CKD) is closely associated with cardiovascular disease. We aimed to examine the association of Life's Essential 8 (LE8), the recently updated measurement of cardiovascular health, with the prevalence of CKD among US adults.

METHODS AND RESULTS

This population-based cross-sectional study used data from the National Health and Nutrition Examination Survey from 2007 to 2018 and included adults aged ≥20 years. Multivariable logistic and restricted cubic spline models were used to assess the associations between LE8 and CKD. Among 24 960 participants, 4437 were determined to have CKD (weighted percentage, 14.11%). After the adjustment of potential confounders, higher LE8 scores were associated with reduced odds of CKD (odds ratio for each 10-point increase, 0.79 [95% CI, 0.76-0.83]), and a nonlinear dose-response relationship was observed. Similar patterns were also identified in the associations of health behavior and health factor scores with CKD. Meanwhile, higher scores for blood glucose (odds ratio, for each 10-point increase, 0.88 [95% CI, 0.87-0.90]) and blood pressure (odds ratio, for each 10-point increase, 0.92 [95% CI, 0.91-0.94]) in the LE8 component are significantly associated with a lower prevalence of CKD. The inversed association of LE8 score and CKD was significantly stronger among middle-aged, male, and coupled participants.

CONCLUSIONS

LE8 was negatively associated with the prevalence of CKD in a nonlinear fashion. Promoting adherence to optimal cardiovascular health levels may be beneficial to reduce the burden of CKD.

Mendelian randomization indicates causal effects of estradiol levels on kidney function in males

Context

Chronic kidney disease (CKD) is a public health burden worldwide. Epidemiological studies observed an association between sex hormones, including estradiol, and kidney function.

Objective

We conducted a Mendelian randomization (MR) study to assess a possible causal effect of estradiol levels on kidney function in males and females.

Design

We performed a bidirectional two-sample MR using published genetic associations of serum levels of estradiol in men (n = 206,927) and women (n = 229,966), and of kidney traits represented by estimated glomerular filtration rate (eGFR, n = 567,460), urine albumin-to-creatinine ratio (UACR, n = 547,361), and CKD (n = 41,395 cases and n = 439,303 controls) using data obtained from the CKDGen Consortium. Additionally, we conducted a genome-wide association study using UK Biobank cohort study data (n = 11,798 men and n = 6,835 women) to identify novel genetic associations with levels of estradiol, and then used these variants as instruments in a one-sample MR.

Results

The two-sample MR indicated that genetically predicted estradiol levels are significantly associated with eGFR in men (beta = 0.077; p = 5.2E-05). We identified a single locus at chromosome 14 associated with estradiol levels in men being significant in the one-sample MR on eGFR (beta = 0.199; p = 0.017). We revealed significant results with eGFR in postmenopausal women and with UACR in premenopausal women, which did not reach statistical significance in the sensitivity MR analyses. No causal effect of eGFR or UACR on estradiol levels was found.

Conclusions

We conclude that serum estradiol levels may have a causal effect on kidney function. Our MR results provide starting points for studies to develop therapeutic strategies to reduce kidney disease.

Renal outcomes in pediatric patients with sickle cell disease: a single center experience in Saudi Arabia

Background

Sickle cell nephropathy (SCN) is a significant complication of sickle cell disease (SCD) with an asymptomatic onset in childhood and potential progression to chronic kidney disease (CKD). The clinical findings of SCN include hyposthenuria, hematuria, proteinuria, hyperfiltration, and CKD. Data on renal manifestation among patients with SCD in Saudi Arabia is lacking. Therefore, this study aimed to evaluate renal outcomes in patients with SCD who visited a hematology clinic at the National Guard Hospital, Jeddah.

Methods

We conducted a retrospective chart review of renal complications in patients with SCD who are within 0-14 years of age and on regular follow-ups at the pediatric hematology clinic in King Abdulaziz Medical City-Jeddah, Saudi Arabia.

Results

Among the 140 patients with SCD, 99 met the inclusion criteria. The median age at diagnosis was 18 (1-108) months. Two SCD phenotypes were observed, with 82 (83%) patients having sickle cell anemia (HbSS) and 17 (17%) having HbS/B+ thalassemia. Of the total patients, 92 (93%) were administered hydroxyurea (HU), with a median starting age of 48 (9-168) months. The most common renal complication observed during routine urinalysis was hematuria (38%), followed by proteinuria (11%). After stratifying the sample into four age groups (0-3 years old, 4-7 years old, 8-11 years old, and 12-14 years old), the mean glomerular filtration rate (GFR) values were 96.16, 101.36, 112.69, and 120.11 ml/min/1.73 m2 respectively. Renal imaging revealed abnormal findings in 27 (29%) patients. The most common abnormality observed on US was increased echogenicity (43%).

Conclusion

SCN is a significant complication of SCD. In this study, we assessed the renal outcomes in pediatric patients with SCD. After analyzing the clinical findings of SCN, we concluded that the presence of renal complications in pediatric patients presented a progressive pattern.

Dialysis vintage is associated with a high prevalence and severity of unpleasant symptoms in patients on hemodialysis

Background: The burden of physical and emotional symptoms caused by somatic illness is present in most dialysis patients. However, it's unclear how symptom burden varies among patients with different dialysis vintages. We sought to examine differences in the prevalence and severity of unpleasant symptoms in hemodialysis patients with diverse dialysis vintage cohorts.Methods: This cross-sectional study included patients on maintenance hemodialysis at the Second Hospital of Anhui Medical University. We used the Dialysis Symptom Index (DSI) to determine the associated unpleasant symptoms, which is a validated survey to assess symptom burden/severity (higher scores indicate more severe symptoms), over June 2022 - September 2022.Results: We studied 146 patients: 35 (24%) had a dialysis vintage of ≤12 months (group 1) and 111 (76%) had a dialysis vintage of >12 months (group 2). Concerning Group 1 patients, the prevalence and severity of unpleasant symptoms were significantly higher in Group 2, the most common individual symptoms included feeling tired or lack of energy and trouble falling asleep (i.e., 75-85% of patients in each group), with dialysis vintage being an independent influencing factor (adjusted OR, 0.19; 95% CI, 0.16 to 0.23). Lower hemoglobin levels, iron stores, and dialysis adequacy levels are correlated with longer dialysis vintage.Conclusion: We observed a high prevalence of unpleasant symptoms and symptom clusters in a diverse dialysis vintages hemodialysis cohort. Further studies are needed to accurately and routinely define the symptom burden of chronic patients with chronic kidney disease (CKD).

Why do we keep ignoring sex in kidney disease?

Throughout the history of nephrology, little attention has been paid to the sex and gender differences in kidney disease. This lack of awareness prevents optimal diagnosis and management of kidney disease. In today's world of precision medicine, it is imperative to appreciate the differential factors regarding gender and kidney disease. This editorial summarizes the up-to-date literature regarding sex and gender differences in kidney disease and considers areas where knowledge is incomplete and where further research is needed. We address sex-specific effects on chronic kidney disease epidemiology; risks of dialysis underdosing and medication overdosing in women; unexplained loss of female sex advantage in life expectancy during dialysis, and impact of sex on diagnosis and management of genetic kidney disease. We also aim to highlight the impact of gender on kidney health and raise awareness of disparities that may be faced by women, and transgender and gender-diverse persons when a male-model approach is used by healthcare systems. By understanding the link between sex and kidney disease, kidney specialists can improve the care and outcomes of their patients. In addition, research on this topic can inform the development of targeted prevention and intervention strategies that address the specific needs and risk factors of different populations.

Inverse association between caffeine intake and albuminuria in US adults: an analysis of NHANES 2005-2016

OBJECTIVES

Albuminuria is a significant biomarker of various kidney diseases and is associated with renal outcome. Recently, caffeine intake has shown potential renoprotective effects. However, the relationship between caffeine intake and albuminuria remains profoundly elusive.

METHODS

We conducted a cross-sectional study aimed to explore the association between caffeine intake and albuminuria in the American adult population using the data acquired from the National Health and Nutrition Examination Survey (NHANES) 2005-2016. Caffeine intake was assessed by 24-h dietary recalls, and albuminuria was assessed by albumin-to-creatinine ratio. Multivariate logistic regression was performed to explore the independent association between caffeine intake and albuminuria. Subgroup analysis and interaction tests were also conducted.

RESULTS

Among 23,060 participants, 11.8% of the individuals exhibited albuminuria, and the prevalence of albuminuria decreased with higher caffeine intake tertiles (Tertile 1: 13%; Tertile 2: 11.9%; Tertile 3: 10.5%; P < 0.001). After adjusted potential confounders, the results of logistic regression indicated that a higher caffeine intake was associated with a decreased risk of albuminuria (OR = 0.903; 95% CI: 0.84, 0.97; P = 0.007), especially in females and the participants aged <60 years and chronic kidney disease stage II.

CONCLUSION

The present study first indicated an inverse correlation between caffeine intake and albuminuria, which further confirmed the potentially protective effects of caffeine on the kidney.

Association Between Cardiovascular Disease and Chronic Kidney Disease Prevalence and Characteristics in Saudi Arabia

Introduction Cardiovascular disease (CVD), including coronary artery disease (CAD), is a leading global cause of death. Chronic kidney disease (CKD) is a significant risk factor, particularly in data-scarce Saudi Arabia, due to shared risk factors. A study aims to assess the CVD-CKD relationship, identifying clinical characteristics and risk factors to improve prevention and care in this context, filling a knowledge gap in Saudi Arabia's healthcare map. Methodology It is a single-center retrospective study aimed at evaluating the relationship between cardiovascular disease and chronic kidney disease, conducted between January 2023 and October 2023. Data was sourced from patient files using a data sheet based on a previous study. The data was cleaned in MS Excel (Redmond, USA) and analyzed in IBM Corp. Released 2022. IBM SPSS Statistics for Windows, Version 29.0. Armonk, NY: IBM Corp. Results Our study contains predominantly males (61%), aged 61-80 (54.1%), with a normal body mass index (BMI) (<25) (61.5%) and a high prevalence of smoking (72.3%). Diabetes, hypertension, and smoking were prevalent risk factors. The relationship between CAD severity, renal dysfunction, and ejection fraction (EF) was explored, emphasizing the association between declining renal function and more advanced CAD stages, as well as the decline in estimated glomerular filtration rate (eGFR) with decreasing EF. Age, smoking, CAD, and decreasing EF were linked to renal dysfunction, while smoking, stroke history, peripheral vascular disease (PVD), BMI, and decreasing EF were associated with CAD stage severity. Conclusion Our study explored that as CAD severity increases, renal function decreases, showing both CVD and CKD connected with each other, and a similar correlation occurs between decreasing EF and decreasing eGFR, revealing significant associations with various risk factors. Further research is warranted to explore potential interventions aimed at mitigating the synergistic impact of CVD and CKD on patient morbidity and mortality.

Prevalence of and risk factors for chronic kidney disease in ten metropolitan areas of China: a cross-sectional study using three kidney damage markers

INTRODUCTION

To estimate the up-to-date prevalence of chronic kidney disease among the health check-up population in economically developed areas of China using estimated glomerular filtration rate, urinary albumin creatinine ratio, and kidney ultrasound.

METHODS

Healthcare data from 38,093 subjects in 10 megalopolises of China who had an annual health check-up in 2021 were used. The overall and stratified prevalence of chronic kidney disease by sex, age, region and comorbidity group was reported. The association between chronic kidney disease and covariates of demographics, and comorbidities were analyzed in the multivariable-adjusted logistic regression model.

RESULTS

A total of 3837 CKD cases were detected meeting any of the three CKD diagnostic criteria, with a crude prevalence of 10.1% in the study population. Using one criterion of decreased glomerular filtration rate, albuminuria and kidney structural abnormalities alone detected 204 (5.3%), 3289 (85.7%) and 563 (14.7%) cases, respectively. The addition of kidney ultrasound detected 427 (11.1%) structural abnormality cases without decreased GFR and albuminuria. The most common abnormalities were renal masses, hydronephrosis due to obstruction and congenital anomalies of kidney and urinary tract. Female, older age, low city-tier, hypertension, diabetes, obesity, hypertriglyceridemia as well as early disease stages such as pre-hypertension, impaired fasting glucose and overweight were significantly associated with chronic kidney disease.

CONCLUSION

Kidney ultrasound helps to amplify the detection of CKD patients, which is a supplement to kidney function and urine protein.