Renal angiotensin I-converting enzyme-deficient mice are protected against aristolochic acid nephropathy.

The renal renin-angiotensin system (RAS) is involved in the development of chronic kidney disease. Here, we investigated whether mice with reduced renal angiotensin I-converting enzyme (ACE-/-) are protected against aristolochic acid nephropathy (AAN). To further elucidate potential molecular mechanisms, we assessed the renal abundances of several major RAS components. AAN was induced using aristolochic acid I (AAI). Glomerular filtration rate (GFR) was determined using inulin clearance and renal protein abundances of renin, angiotensinogen, angiotensin I-converting enzyme (ACE) 2, and Mas receptor (Mas) were determined in ACE-/- and C57BL/6J control mice by Western blot analyses. Renal ACE activity was determined using a colorimetric assay and renal angiotensin (Ang) (1-7) concentration was determined by ELISA. GFR was similar in vehicle-treated mice of both strains. AAI decreased GFR in controls but not in ACE-/- mice. Furthermore, AAI decreased renal ACE activity in controls but not in ACE-/- mice. Vehicle-treated ACE-/- mice had significantly higher renal ACE2 and Mas protein abundances than controls. AAI decreased renal ACE2 protein abundance in both strains. Furthermore, AAI increased renal Mas protein abundance, although the latter effect did not reach statistical significance in the ACE-/- mice. Renal Ang(1-7) concentration was similar in vehicle-treated mice of both strains. AAI increased renal Ang(1-7) concentration in the ACE-/- mice but not in the controls. Mice with reduced renal ACE are protected against AAN. Our data suggest that in the face of renal ACE deficiency, AAI may activate the ACE2/Ang(1-7)/Mas axis, which in turn may deploy its reno-protective effects.

Carotid intima-media thickness and atherosclerotic plaques are associated with renal function decline: a 14-year longitudinal population-based study.

BACKGROUND: Chronic kidney disease (CKD) leads to increased morbidity and mortality. The underlying causes of CKD are often similar to those of atherosclerosis. We investigated whether carotid atherosclerotic parameters are associated with renal function decline. METHODS: Within the population-based Study of Health in Pomerania (SHIP), Germany, 2904 subjects were observed over 14 years. The carotid intima-media thickness (cIMT) as well as carotid plaques were measured by standardized B-mode ultrasound protocol. CKD is defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 and albuminuria as urinary albumin-creatinine ratio (ACR) ≥30 mg/g. eGFR was calculated by the full age spectrum (FAS) equation and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Mixed models were applied to associate carotid parameters with change in renal function longitudinally and adjusted for confounding. RESULTS: The age range of the study sample was 25-86 years with a median of 54 years at baseline. In longitudinal analyses, subjects with high cIMT and the presence of plaques at baseline showed a greater decrease in eGFR (cIMT: FAS-eGFR: P < .001, CKD-EPI-eGFR: P < .001; plaques: FAS-eGFR: P < .001, CKD-EPI-eGFR: n.s.) as well as an increased risk of developing CKD during the follow-up (cIMT: FAS-eGFR: P = .001, CKD-EPI-eGFR: P = .04; plaques: FAS-eGFR: P = .008, CKD-EPI-eGFR: P = .001). There was no association between atherosclerotic parameters and the risk of developing albuminuria. CONCLUSIONS: cIMT and carotid plaques are associated with renal function decline as well as CKD in a population-based sample. Furthermore, the FAS equation adapts best to this study population.

[Development of quality indicators for the care of patients with chronic kidney disease : Results of a structured consensus process using the Delphi technique]. / Entwicklung von Qualitätsindikatoren für die Versorgung von Patient:innen mit chronischer Nierenerkrankung : Ergebnisse einer strukturierten Konsensfindung mittels Delphi-Verfahrens.

BACKGROUND: Chronic kidney disease (CKD) is a common condition, especially in the elderly. In order to prevent progression and complications of the disease, guideline-adherent outpatient care of patients with CKD should be prioritized. Quality indicators (QIs) can be used to measure and evaluate the quality of ambulatory care for patients with CKD. QIs specifically made for evaluating CKD care in Germany are not yet available. The goal of this work was to develop QIs for the quality assessment of outpatient care for patients over the age of 70 with CKD not requiring dialysis. MATERIALS AND METHODS: QIs were operationalized from the recommendations of the German national guideline for CKD and others were proposed based on a published review of international QIs. The resulting QIs were divided into sets based on routine data (e.g., health insurance billing data) and data collection in practices (chart review). A panel of experts from various disciplines as well as a patient representative evaluated the proposed QIs in a two-stage Delphi process via online survey in October 2021 and January 2022 and a final consensus conference in March 2022. In addition, ranking lists of the most important QIs from each set were created. RESULTS: An incidence indicator and a prevalence indicator were established; these were not subject to vote. Further, 21 QIs were voted upon by the expert panel. The seven most important QIs in each set (billing data or chart review) were selected. Only one QI was rated by the expert panel as not suitable for additional use in adults under the age of 70 years. DISCUSSION: The QIs will enable the evaluation of the quality of outpatient care for patients with CKD with the long-term aim of optimizing guideline-adherent outpatient care.

Potentially inappropriate medication in patients with chronic kidney disease and elderly patients.

BACKGROUND: Most patients with chronic kidney disease (CKD) are old, comorbid, and subjected to polypharmacy. This study describes prevalence and predictors of potentially inappropriate medication (PIM) in CKD patients. MATERIALS AND METHODS: Medication plans of CKD patients of the "Greifswald Approach to Individualized Medicine" cross-sectional study (GANI_MED) were checked for PIM based on kidney function (PIM-K) and PIM for elderly patients (PIM-E). PIM-K were defined by prescription instructions of product labeling. PIM-E were defined by BEERS, -PRISCUS, and FORTA criteria. Predictors for PIM were identified through multiple stepwise regression. RESULTS: 375 patients were included (age: 67.9 ± 13.5 years; estimated glomerular filtration rate (eGFR): 23.3 ± 18.6 mL/min/1.73m2; prescriptions: 11.1 ± 4.7). 44.5% of all CKD patients had PIM-K, and 43.2 to 79.0% of all elderly patients had PIM-E. Polypharmacy and reduced eGFR were predictors for PIM. The risk for PIM-K was increased by 3.8 (95% confidence interval (CI): 1.5 - 9.6) with 10 or more prescriptions and by 8.7 (95% CI: 1.3 - 58.5) with an eGFR below 30 mL/min/1.73m2. On average, elderly patients with 10 or more prescriptions had 3.0 ± 1.7 PIM-E. CONCLUSION: Polypharmacy, PIM-K, and PIM-E affect many CKD patients and can lead to adverse events. Deprescribing and targeted prescribing may improve the outcome of CKD patients and elderly patients.

Referral criteria for chronic kidney disease: implications for disease management and healthcare expenditure-analysis of a population-based sample.

BACKGROUND: Clinical practice guidelines recommend specialist referral according to different criteria. The aim was to assess recommended and observed referral rate and health care expenditure according to recommendations from: • Kidney Disease Improving Global Outcomes (KDIGO,2012) • National Institute for Health and Care Excellence (NICE,2014) • German Society of Nephrology/German Society of Internal Medicine (DGfN/DGIM,2015) • German College of General Practitioners and Family Physicians (DEGAM,2019) • Kidney failure risk equation (NICE,2021) METHODS: Data of the population-based cohort Study of Health in Pomerania were matched with claims data. Proportion of subjects meeting referral criteria and corresponding health care expenditures were calculated and projected to the population of Mecklenburg-Vorpommern. RESULTS: Data from 1927 subjects were analysed. Overall proportion of subjects meeting referral criteria ranged from 4.9% (DEGAM) to 8.3% (DGfN/DGIM). The majority of patients eligible for referral were ≥ 60 years. In subjects older than 60 years, differences were even more pronounced, and rates ranged from 9.7% (DEGAM) to 16.5% (DGfN/DGIM). Estimated population level costs varied between €1,432,440 (DEGAM) and €2,386,186 (DGfN/DGIM). From 190 patients with eGFR < 60 ml/min, 15 had a risk of end stage renal disease > 5% within the next 5 years. CONCLUSIONS: Applying different referral criteria results in different referral rates and costs. Referral rates exceed actually observed consultation rates. Criteria need to be evaluated in terms of available workforce, resources and regarding over- and underutilization of nephrology services.

Monitoring and management of chronic kidney disease in ambulatory care - analysis of clinical and claims data from a population-based study.

BACKGROUND: Although chronic kidney disease (CKD) is highly prevalent in the general population, little research has been conducted on CKD management in ambulatory care. Objective was to assess management and quality of care by evaluating CKD coding in ambulatory care, patient diagnosis awareness, frequency of monitoring and whether appropriate patients are referred to nephrology. METHODS: Clinical data from the population-based cohort Study of Health in Pomerania (SHIP-START) were matched with claims data of the Association of Statutory Health Insurance Physicians. Quality of care was evaluated according international and German recommendations. RESULTS: Data from 1778 participants (56% female, mean age 59 years) were analysed. 10% had eGFR < 60 ml/min/1.73m2 (mean age 74 years), 15% had albuminuria. 21% had CKD as defined by KDIGO. 20% of these were coded and 7% self-reported having CKD. Coding increased with GFR stage (G3a 20%, G3b 61%, G4 75%, G5 100%). Serum creatinine and urinary dip stick testing were billed in the majority of all participants regardless of renal function. Testing frequency partially surpassed recommendations. Nephrology consultation was billed in few cases with stage G3b-G4. CONCLUSION: CKD coding increased with stage and was performed reliably in stages ≥ G4, while CKD awareness was low. Adherence to monitoring and referral criteria varied, depending on the applicability of monitoring criteria. For assessing quality of care, consent on monitoring, patient education, referral criteria and coordination of care needs to be established, accounting for patient related factors, including age and comorbidity. TRIAL REGISTRATION: This study was prospectively registered as DRKS00009812 in the German Clinical Trials Register (DRKS).

Long-term prognosis after kidney donation: a propensity score matched comparison of living donors and non-donors from two population cohorts.

BACKGROUND: Live donor nephrectomy is a safe procedure. However, long-term donor prognosis is debated, necessitating high-quality studies. METHODS: A follow-up study of 761 living kidney donors was conducted, who visited the outpatient clinic and were propensity score matched and compared to 1522 non-donors from population-based cohort studies. Primary outcome was kidney function. Secondary outcomes were BMI (kg/m2), incidences of hypertension, diabetes, cardiovascular events, cardiovascular and overall mortality, and quality of life. RESULTS: Median follow-up after donation was 8.0 years. Donors had an increase in serum creatinine of 26 µmol/l (95% CI 24-28), a decrease in eGFR of 27 ml/min/1.73 m2 (95% CI - 29 to - 26), and an eGFR decline of 32% (95% CI 30-33) as compared to non-donors. There was no difference in outcomes between the groups for ESRD, microalbuminuria, BMI, incidence of diabetes or cardiovascular events, and mortality. A lower risk of new-onset hypertension (OR 0.45, 95% CI 0.33-0.62) was found among donors. The EQ-5D health-related scores were higher among donors, whereas the SF-12 physical and mental component scores were lower. CONCLUSION: Loss of kidney mass after live donation does not translate into negative long-term outcomes in terms of morbidity and mortality compared to non-donors. TRIAL REGISTRATION: Dutch Trial Register NTR3795.

Long-term Association of Periodontitis With Decreased Kidney Function.

RATIONALE & OBJECTIVE: Previous studies have yielded inconclusive findings regarding the relationship between periodontitis and kidney function. We sought to investigate whether periodontitis is associated with subsequent decreases in kidney function (reductions in estimated glomerular filtration rate [eGFR] and increased urinary albumin-creatinine ratio [UACR]) in the general population. STUDY DESIGN: Population-based cohort study. SETTING & PARTICIPANTS: We used baseline and 11-year follow-up data from 2,297 and 1,512 adult participants, respectively, in the Study of Health in Pomerania (SHIP). Age range was limited to 20 to 59 years to avoid the potential influence of tooth loss. EXPOSURES: Periodontal status defined by periodontal pocket probing depth (PPD) and clinical attachment level. Mean levels and the percentage of sites ≥ 3mm was determined for either all sites (PPD) or interproximal sites (clinical attachment level). All PPDs≥4mm were summed to calculate the total PPD. OUTCOMES: GFR estimated from serum creatinine and serum cystatin C (eGFRcr-cys). Moderately increased albuminuria defined as UACR>30mg/g. ANALYTICAL APPROACH: Adjusted linear and logistic mixed regression models. RESULTS: At baseline and follow-up, average eGFRcr-cys was 118.3 and 105.0mL/min/1.73m2, respectively. Using mixed models, no consistently significant associations between periodontitis variables and eGFRcr-cys were detected. Long-term changes in UACR were inconsistently associated with periodontitis measures. After imputation of missing data, associations were either attenuated or no longer detectable. LIMITATIONS: Because periodontal assessments were performed using a partial recording protocol, periodontal disease severity estimates might have been underestimated, resulting in attenuated effect estimates. CONCLUSIONS: We found no consistent evidence for an association between periodontitis and decreased kidney function. In contrast to previous studies, these results do not support the hypothesis that periodontitis is an important risk factor for chronic kidney disease.

Staphylococcus aureus colonization in hemodialysis patients: a prospective 25 months observational study.

BACKGROUND: Dialysis patients are frequently exposed to Staphylococcus aureus due to stays in dialysis centers, hospitals or rest homes. The hemodialysis vascular access is a potential entry site for S. aureus, in particular when using a central venous catheter (CVC) which increases the risk of sepsis compared to arteriovenous (AV) fistula. We prospectively followed a cohort of 86 hemodialysis patients from an outpatient dialysis center over 25 months analyzing S. aureus carrier status, S. aureus infection rates and mortality. METHODS: Demographic data and patients´ medical histories were collected and followed from all hemodialysis patients. Blood samples, nasal swabs and swabs from the hemodialysis vascular access site were taken every six months for a period of 25 months and tested for S. aureus. Strains were cultured and further characterized by spa PCR and microarray-based genotyping. Resulting data were compared with those from the general population. RESULTS: In cross-sectional analyses, an average of 40% of hemodialysis patients were S. aureus carriers compared to 27% in the general population. Longitudinally, a total of 65% were S. aureus carriers: 16% were persistent carriers, 43% were intermittently colonized. The most common S. aureus lineage in the dialysis patient cohort was the clonal complex (CC) 8 and the spa type t008, while in the general population, the clonal complex CC30 dominates. During the study period, we observed six S. aureus-associated blood stream infections with one S. aureus attributable death. S. aureus carriers with an AV fistula were more densely colonized in the nasal mucosa compared to patients with a CVC. Overall mortality was lower for hemodialysis patients with a positive S. aureus carrier status compared to non-carriers (hazard ratio of 0.19). CONCLUSIONS: Compared to the general population, hemodialysis patients were more frequently colonized with S. aureus and displayed both different S. aureus colonization densities as well as lineages, possibly explained by more frequent exposure to health care environments. The lower overall mortality in carriers compared to non-carriers is intriguing and will be investigated in detail in the future. TRIAL REGISTRATION: ISRCTN 14385893 , 2. October 2018, retrospectively registered.

BDNF: mRNA expression in urine cells of patients with chronic kidney disease and its role in kidney function.

Podocyte loss and changes to the complex morphology are major causes of chronic kidney disease (CKD). As the incidence is continuously increasing over the last decades without sufficient treatment, it is important to find predicting biomarkers. Therefore, we measured urinary mRNA levels of podocyte genes NPHS1, NPHS2, PODXL and BDNF, KIM-1, CTSL by qRT-PCR of 120 CKD patients. We showed a strong correlation between BDNF and the kidney injury marker KIM-1, which were also correlated with NPHS1, suggesting podocytes as a contributing source. In human biopsies, BDNF was localized in the cell body and major processes of podocytes. In glomeruli of diabetic nephropathy patients, we found a strong BDNF signal in the remaining podocytes. An inhibition of the BDNF receptor TrkB resulted in enhanced podocyte dedifferentiation. The knockdown of the orthologue resulted in pericardial oedema formation and lowered viability of zebrafish larvae. We found an enlarged Bowman's space, dilated glomerular capillaries, podocyte loss and an impaired glomerular filtration. We demonstrated that BDNF is essential for glomerular development, morphology and function and the expression of BDNF and KIM-1 is highly correlated in urine cells of CKD patients. Therefore, BDNF mRNA in urine cells could serve as a potential CKD biomarker.

Diagnosis and management of non-dialysis chronic kidney disease in ambulatory care: a systematic review of clinical practice guidelines.

BACKGROUND: Chronic kidney disease (CKD) is age-dependent and has a high prevalence in the general population. Most patients are managed in ambulatory care. This systematic review provides an updated overview of quality and content of international clinical practice guidelines for diagnosis and management of non-dialysis CKD relevant to patients in ambulatory care. METHODS: We identified guidelines published from 2012-to March 2018 in guideline portals, databases and by manual search. Methodological quality was assessed with the Appraisal of Guidelines for Research and Evaluation II instrument. Recommendations were extracted and evaluated. RESULTS: Eight hundred fifty-two publications were identified, 9 of which were eligible guidelines. Methodological quality ranged from 34 to 77%, with domains "scope and purpose" and "clarity of presentation" attaining highest and "applicability" lowest scores. Guidelines were similar in recommendations on CKD definition, screening of patients with diabetes and hypertension, blood pressure targets and referral of patients with progressive or stage G4 CKD. Definition of high risk groups and recommended tests in newly diagnosed CKD varied. CONCLUSIONS: Guidelines quality ranged from moderate to high. Guidelines generally agreed on management of patients with high risk or advanced CKD, but varied in regarding the range of recommended measurements, the need for referrals to nephrology, monitoring intervals and comprehensiveness. More research is needed on efficient management of patients with low risk of CKD progression to end stage renal disease.

Urinary Angiotensinogen and Renin Excretion are Associated with Chronic Kidney Disease.

BACKGROUND/AIMS: Several studies sought to identify new biomarkers for chronic kidney disease (CKD). As the renal renin-angiotensin system is activated in CKD, urinary angiotensinogen or renin excretion may be suitable candidates. We tested whether urinary angiotensinogen or renin excretion is elevated in CKD and whether these parameters are associated with estimated glomerular filtration rate (eGFR). We further tested whether urinary angiotensinogen or renin excretion may convey additional information beyond that provided by albuminuria. METHODS: We measured urinary and plasma angiotensinogen, renin, albumin and creatinine in 177 CKD patients from the Greifswald Approach to Individualized Medicine project and in 283 healthy controls from the Study of Health in Pomerania. The urinary excretion of specific proteins is given as protein-to-creatinine ratio. Receiver operating characteristic (ROC) curves, spearman correlation coefficients and linear regression models were calculated. RESULTS: Urinary angiotensinogen [2,511 (196-31,909) vs. 18.6 (8.3-44.0) pmol/g, *P<0.01] and renin excretion [0.311 (0.135-1.155) vs. 0.069 (0.045-0.148) pmol/g, *P<0.01] were significantly higher in CKD patients than in healthy controls. The area under the ROC curve was significantly larger when urinary angiotensinogen, renin and albumin excretion were combined than with urinary albumin excretion alone. Urinary angiotensinogen (ß-coefficient -2.405, standard error 0.117, P<0.01) and renin excretion (ß-coefficient -0.793, standard error 0.061, P<0.01) were inversely associated with eGFR. Adjustment for albuminuria, age, sex, systolic blood pressure and body mass index did not significantly affect the results. CONCLUSION: Urinary angiotensinogen and renin excretion are elevated in CKD patients. Both parameters are negatively associated with eGFR and these associations are independent of urinary albumin excretion. In CKD patients urinary angiotensinogen and renin excretion may convey additional information beyond that provided by albuminuria.

Discrepant post filter ionized calcium concentrations by common blood gas analyzers in CRRT using regional citrate anticoagulation.

INTRODUCTION: Ionized calcium (iCa) concentration is often used in critical care and measured using blood gas analyzers at the point of care. Controlling and adjusting regional citrate anticoagulation (RCA) for continuous renal replacement therapy (CRRT) involves measuring the iCa concentration in two samples: systemic with physiological iCa concentrations and post filter samples with very low iCa concentrations. However, modern blood gas analyzers are optimized for physiological iCa concentrations which might make them less suitable for measuring low iCa in blood with a high concentration of citrate. We present results of iCa measurements from six different blood gas analyzers and the impact on clinical decisions based on the recommendations of the dialysis' device manufacturer. METHOD: The iCa concentrations of systemic and post filter samples were measured using six distinct, frequently used blood gas analyzers. We obtained iCa results of 74 systemic and 84 post filter samples from patients undergoing RCA for CRRT at the University Medicine of Greifswald. RESULTS: The systemic samples showed concordant results on all analyzers with median iCa concentrations ranging from 1.07 to 1.16 mmol/L. The medians of iCa concentrations for post filter samples ranged from 0.21 to 0.50 mmol/L. Results of >70% of the post filter samples would lead to major differences in decisions regarding citrate flow depending on the instrument used. CONCLUSION: Measurements of iCa in post filter samples may give misleading information in monitoring the RCA. Recommendations of the dialysis manufacturer need to be revised. Meanwhile, little weight should be given to post filter iCa. Reference methods for low iCa in whole blood containing citrate should be established.

Regional variation of chronic kidney disease in Germany: results from two population-based surveys.

BACKGROUND/AIMS: Due to the increasing prevalence of risk factors for chronic kidney disease (CKD), kidney dysfunction becomes a major public health problem. We investigated the CKD prevalence and determined to what extent the variation of risk factors explains the different CKD prevalence in Germany. METHODS: We analyzed data from 6,054 participants, aged 31 to 82 years, from the Study of Health in Pomerania (SHIP-1) in Northeast Germany and the Cooperative Health Research in the Region of Augsburg (KORA F4) Study in Southern Germany. Regional differences in selected percentiles corresponding to the cutpoints for estimated glomerular filtration rate (eGFR, <60 ml/min per 1.73 m(2)) and albumin-to-creatinine ratio (ACR, ≥30 mg/g) were tested using quantile regression models that adjusted for CKD risk factors. RESULTS: The prevalence of decreased eGFRcreatinine-cystatinC (5.9 vs. 3.1 %, p <0.001) and albuminuria (20.2 vs. 8.8 %, p<0.001) were higher in SHIP-1 than in KORA F4. The differential distribution of risk factors explained 18-21% of the regional differences of decreased eGFRcreatinine-cystatinC and high ACR. CONCLUSIONS: The CKD prevalence is higher in Northeast than in Southern Germany. Differences in the prevalence of risk factors partly explain the higher disease burden of CKD in Northeast than in Southern Germany.

Cohort profile: Greifswald approach to individualized medicine (GANI_MED).

BACKGROUND: Individualized Medicine aims at providing optimal treatment for an individual patient at a given time based on his specific genetic and molecular characteristics. This requires excellent clinical stratification of patients as well as the availability of genomic data and biomarkers as prerequisites for the development of novel diagnostic tools and therapeutic strategies. The University Medicine Greifswald, Germany, has launched the "Greifswald Approach to Individualized Medicine" (GANI_MED) project to address major challenges of Individualized Medicine. Herein, we describe the implementation of the scientific and clinical infrastructure that allows future translation of findings relevant to Individualized Medicine into clinical practice. METHODS/DESIGN: Clinical patient cohorts (N > 5,000) with an emphasis on metabolic and cardiovascular diseases are being established following a standardized protocol for the assessment of medical history, laboratory biomarkers, and the collection of various biosamples for bio-banking purposes. A multi-omics based biomarker assessment including genome-wide genotyping, transcriptome, metabolome, and proteome analyses complements the multi-level approach of GANI_MED. Comparisons with the general background population as characterized by our Study of Health in Pomerania (SHIP) are performed. A central data management structure has been implemented to capture and integrate all relevant clinical data for research purposes. Ethical research projects on informed consent procedures, reporting of incidental findings, and economic evaluations were launched in parallel.

Complement Activation in Nephrotic Glomerular Diseases.

The nephrotic syndrome holds significant clinical importance and is characterized by a substantial protein loss in the urine. Damage to the glomerular basement membrane or podocytes frequently underlies renal protein loss. There is an increasing belief in the involvement of the complement system, a part of the innate immune system, in these conditions. Understanding the interactions between the complement system and glomerular structures continually evolves, challenging the traditional view of the blood-urine barrier as a passive filter. Clinical studies suggest that a precise inhibition of the complement system at various points may soon become feasible. However, a thorough understanding of current knowledge is imperative for planning future therapies in nephrotic glomerular diseases such as membranous glomerulopathy, membranoproliferative glomerulonephritis, lupus nephritis, focal segmental glomerulosclerosis, and minimal change disease. This review provides an overview of the complement system, its interactions with glomerular structures, and insights into specific glomerular diseases exhibiting a nephrotic course. Additionally, we explore new diagnostic tools and future therapeutic approaches.

Age- and Sex-Specific Reference Values for Renal Volume and Association with Risk Factors for Chronic Kidney Disease in a General Population-An MRI-Based Study.

BACKGROUND: Renal volume (RV) is associated with renal function and with a variety of cardiovascular risk factors (CVRFs). We analysed RV using magnetic resonance imaging (MRI) in a large population-based study (Study of Health in Pomerania; SHIP-TREND) to find sex- and age-specific reference values for RV and to test the influence of several markers on RV. The main objective is to describe reference values for RV in people from the general population without kidney disease. METHODS: 1815 participants without kidney disease (930 women) aged 21-81 years were included in our study. Right and left RV with and without body surface area (BSA) indexation were compared among three age groups (22-39 years, 40-59 years, 60-81 years) by median and interquartile range and tested separately in women and men. RESULTS: The estimated glomerular filtration rate (eGFR), serum uric acid, and right and left RV were higher in men compared to women (all p < 0.001). Left kidneys were larger than right kidneys (both sexes). With age, RV showed a continuously decreasing trend in women and an upside-down U-shaped relation in men. In multivariable linear regression models, current smoking (ß = 14.96, 95% CI 12.12; 17.79), BSA (ß = 97.66, 95% CI 90.4; 104.93), diastolic blood pressure (ß = 0.17, 95% CI 0.01; 0.32), and eGFR (ß = 0.57, 95% CI 0.50; 0.65) were positively associated with both left and right RV, whereas uric acid (ß = -0.03, 95% CI -0.05; -0.01) showed an inverse association with RV. Interestingly, the same eGFR correlated with higher RV in men compared to women. CONCLUSION: Reference values for RV are different for age groups and sex. For any given age, female kidneys are smaller than male kidneys. RV associates positively with eGFR, but for any chosen eGFR, renal volume in females is lower compared to males. RV decreases with age, but in men showed a U-shaped correlation. This may reflect hyperfiltration and glomerular hypertrophy associated with the presence of CVRF in middle-aged males.

Childhood maltreatment and risk of metabolic dysfunction-associated steatotic liver disease - Evidence of sex-specific associations in the general population.

BACKGROUND AND AIMS: Childhood maltreatment (CM) is linked to self-reported liver disease in adulthood. However, specific diagnostic entities, e.g., metabolic dysfunction-associated steatotic liver disease (MASLD) as the most frequent chronic liver disease, and sex-differences have previously not been considered. METHODS: Cross-sectional analyses were conducted in 4188 adults from a population-based cohort in Northeastern Germany after excluding individuals with excessive alcohol consumption, cirrhosis, or chronic viral hepatitis. CM-exposure was assessed using the Childhood Trauma Questionnaire (CTQ). Liver-related outcomes included serologic liver enzymes, fibrosis-4 score (FIB-4) and, in 1863 subjects who underwent magnetic resonance imaging examination, liver fat content. Sex-stratified linear regression and logistic regression models predicting liver-related outcomes and risk for MASLD, respectively, from overall CTQ scores were adjusted for age, school education, alcohol consumption, and waist circumference. Exploratory analyses investigated effects of CTQ-subscales on liver-related outcomes and risk for MASLD. RESULTS: In both sexes, overall CM-exposure was associated with higher levels of serum aspartate aminotransferase and FIB-4 score. In men, effects were mainly driven by physical abuse, and in women by emotional neglect. Only in men, overall CM-exposure (ß = 0.70, 95%-CI 0.26-1.13, p = 0.002) and four CTQ-subscales were associated with greater liver fat content, and physical abuse (aOR = 1.22, 95%-CI 1.02-1.46, p = 0.034) and physical neglect (aOR = 1.25, 95%-CI 1.04-1.49, p = 0.015) were associated with higher risk for MASLD. CONCLUSIONS: These results suggest sex differences in the association between CM and objective serum and imaging markers of MASLD in adulthood. For men especially, a history of CM-exposure may increase risk of developing MASLD in adulthood.

Sex-specific associations of childhood maltreatment with obesity-related traits - The Study of Health in Pomerania (SHIP).

BACKGROUND: Child maltreatment (CM) is linked to obesity in adulthood. However, sex-differences and direct measurements of body fat have previously been insufficiently considered in this context. OBJECTIVE: To assess sex-specific associations of CM with anthropometric markers of overweight/obesity and direct measures of body fat. PARTICIPANTS AND SETTING: Analyses were conducted in 4006 adults from a population-based cohort in Northeastern Germany (SHIP-TREND-0). METHODS: CM was assessed using the Childhood Trauma Questionnaire (CTQ). Obesity-related traits included anthropometric indicators (i.e., height, weight, body mass index [BMI], waist [WC] and hip circumference [HC], waist-to-hip ratio [WHR], waist-to-height ratio [WHtR]), fat mass (FM) and fat-free mass (FFM) derived from bioelectrical impedance analysis (BIA), and subcutaneous (SAT) and visceral adipose tissue (VAT) ascertained using magnetic resonance imaging (MRI). Sex-stratified linear regression models predicting obesity-related traits from total CTQ scores were adjusted for age and education. Exploratory analyses investigated effects of CTQ subscales on obesity-related traits. RESULTS: In men, CM was positively associated with WHtR (ß = 0.04; p = .030) and VAT (ß = 0.02; p = .031) and inversely with body height (ß = -0.05; p = .010). In women, CM-exposure was positively associated with body weight (ß = 0.07; p = .018), BMI (ß = 0.03; p = .013), WC (ß = 0.07; p = .005), HC (ß = 0.05; p = .046), WHR (ß = 0.03; p = .015), WHtR (ß = 0.04; p = .006), FM (ß = 0.04; p = .006), and SAT (ß = 0.06; p = .041). In both sexes, effects were mainly driven by exposure to emotional and physical abuse. CONCLUSIONS: Results suggest that associations between CM-exposure and obesity-related traits in adulthood are primarily present in women. This may have implications for sex-specific obesity-related cardiometabolic risk after CM.