Investigating the causal association of generalized and abdominal obesity with microvascular complications in patients with type 2 diabetes: A community-based prospective study

AIM

The paradoxical protective association between overweight/obesity and diabetic microvascular complications (DMC), a phenomenon well-known as the obesity paradox, has been considered a non-causal association based on methodological influences. We aimed to investigate the association of generalized and abdominal obesity, as measured by body mass index (BMI) and waist circumference (WC), respectively, with DMC in patients with type 2 diabetes (T2D), using a causal inference approach.

MATERIALS AND METHODS

We enrolled 1436 patients with clinically diagnosed T2D but not DMC at baseline in a community-based prospective cohort in China between 2017 and 2019 and followed them annually until 2022 with new-onset DMC recorded. Marginal structural Cox models with inverse probability weighting were constructed to determine the causal association. Subgroup analyses were performed to identify potential effect modifiers.

RESULTS

We observed 360 incident DMC cases, including 109 cases of diabetic nephropathy (DN) and 277 cases of diabetic retinopathy (DR) during four follow-up visits. Multivariable-adjusted hazard ratios (95% confidence intervals) for overall DMC, DN and DR were 1.037 (1.005-1.071), 1.117 (1.062-1.175) and 1.018 (0.980-1.059) for 1 kg/m2 increase in BMI, and 1.005 (0.994-1.017), 1.034 (1.018-1.051) and 1.000 (0.987-1.014) for 1 cm increase in WC, respectively. Similar patterns were observed across the BMI and WC categories, while the positive association appeared to be more pronounced in women.

CONCLUSIONS

Generalized but not abdominal obesity was associated with an increased risk for the overall DMC, whereas both obesities were causally related to DN, albeit not DR, in T2D. Routine weight management should not be neglected in diabetes care, particularly in women.

Assessment of regional and total skeletal metabolism using 18F-NaF PET/CT in patients with chronic kidney disease

OBJECTIVE

The study aims to assess regional and total bone metabolic activity in patients with chronic kidney disease using Na[18F]F PET and correlation between semi-quantitative indices and blood parameters.

METHODS

Seventy-two subjects (mean age 61.8 ± 13.8 years) were included. Of these 24/72 patients had end-stage renal disease (ESRD) (GFR < 15 mL/min/1.73 m2), 38/72 had chronic kidney disease (CKD) (GFR between 60 and 15 mL/min/1.73 m2), and 10/72 were controls with normal renal function. All subjects underwent Na[18F]F PET-CT with a dose activity of 0.06 mCi/Kg. Regional and total skeletal metabolism were assessed with mean SUVs in a skeletal volume of interest (VOI), bone to soft tissue index (B/S), global SUV mean (GSUV mean) of the whole bone, and uptake in the femoral neck.

RESULTS

Statistically significant differences were observed in a number of 18F-NaF metrics like femoral neck metabolism in CKD and ERSD groups in comparison to control in right (P = 0.003) and left femur (P = 0.006), bone to soft tissue index in the femur (P = 0.016) and GSUV5 (P = 0.006). There is also a significant difference in SUV mean in lumbar vertebrae (L1-L4) among CKD, ESRD, and controls. There was a moderate correlation between 18F-NaF PET scan uptake and blood parameters such as ALP and PTH. Na[18F]F uptake parameters were significantly different in low versus high bone turnover state.

CONCLUSIONS

The assessment of total skeleton and regional metabolism and bone turnover in CKD patients is feasible with Na[18F]F PET. Na[18F]F can help to detect early changes in bone metabolism and assess the progression of bone disease in this complex condition. Quantification with Na[18F]F PET might provide better assessment of the bone turnover. The difference in Na[18F]F uptake in CKD compared to controls is likely related to a change in bone turnover which, however, requires further validation.

Tc-99m-MIBI SPECT/CT imaging to diagnose secondary hyperparathyroidism after parathyroid forearm transplantation

This article report a 40-year-old male patient who underwent total thyroidectomy and forearm auto-transplantation in another hospital for secondary hyperparathyroidism. After 4 years of follow-up, the level of parathyroid hormone continued to increase, and ultrasound showed nodules in the neck and right forearm, which were considered to be of parathyroid origin. Technetium 99m sestamibi single photon emission computed tomography and computed tomography (Tc-99m-MIBI SPECT/CT) imaging showed increased radioactive uptake in the submuscular soft tissue nodule of the right medial forearm, maximum standardized uptake value (SUVmax) is 0.98, which was identified as transplanted functioning parathyroid tissue. No parathyroid imaging activity was found in the neck. The patient then underwent partial removal of ectopic parathyroid tissue from the right forearm. Pathological examination confirmed parathyroid tissue, and removal was followed by a rapid decline in serum parathyroid hormone levels.

Impact of iodine contrast media on gamma camera-based GFR and factors affecting the difference between serum creatinine-based estimated GFR and Gate's GFR

OBJECTIVE

We aimed to elucidate the factors underlying the difference between estimated glomerular filtration rate (eGFR) calculated from serum creatinine and Gate's GFR (gGFR) measured using technetium-99m diethylene triamine pentaacetic acid ( 99m Tc-DTPA) scintigraphy.

METHODS

This study was based on consecutive patients who underwent 99m Tc-DTPA scintigraphy at our hospital between January 2021 and December 2022 and whose blood serum creatinine data were obtained on the same day as the 99m Tc-DTPA scintigraphy. Relationships between the ratio of gGFR and eGFR (gGFR/eGFR) and age, sex, BMI, visceral fat, psoas muscle index (PMI), serum blood urea nitrogen, and creatinine level were investigated based on 75 patients. Additionally, for 44 patients who had two or more follow-up DTPA studies, we compared gGFR values for studies that used iodine contrast media (ICM) for computed tomography before same-day 99m Tc-DTPA studies and those that did not in the same patients.

RESULTS

Weak correlations were observed between gGFR/eGFR and PMI ( r  = 0.30), BMI ( r  = 0.24), and the visceral fat area ( r  = 0.33). Multi-regression analyses showed that gGFR/eGFR was correlated with PMI ( β  = 0.34, P  < 0.01) and approached significance with the visceral fat area ( β  = 0.24, P  = 0.05). A significant difference was observed in gGFR between patients who received ICM before the 99m Tc-DTPA renogram and those who did not ( P  < 0.001, eGFR 80.5 ± 19.0 vs. 91.7 ± 27.8 ml/min).

CONCLUSION

ICM administration temporarily decreased gGFR, and increased muscle mass increased the difference between eGFR and gGFR values.

Integrating the patient voice: patient-centred and equitable clinical risk prediction for kidney health and disease

PURPOSE OF REVIEW

Personalized approaches to care are increasingly common in clinical nephrology. Although risk prediction models are developed to estimate the risk of kidney-disease related outcomes, they infrequently consider the priorities of patients they are designed to help.

RECENT FINDINGS

This review discusses certain steps in risk prediction tool development where patients and their priorities can be incorporated. Considering principles of equity throughout the process has been the focus of recent literature.

SUMMARY

Applying a person-centred lens has implications for several aspects of risk prediction research. Incorporating the patient voice may involve partnering with patients as researchers to identify the target outcome for the tool and/or determine priorities for outcomes related to the kidney disease domain of interest. Assessing the list of candidate predictors for associations with inequity is important to ensure the tool will not widen disparity for marginalized groups. Estimating model performance using person-centred measures such as model calibration may be used to compare models and select a tool more useful to inform individual treatment decisions. Finally, there is potential to include patients and families in determining other elements of the prediction framework and implementing the tool once development is complete.

The association between blood pressure variability and renal damage in patients with primary aldosteronism

This research examines the association between blood pressure variability (BPV) and renal damage in a cohort of 129 primary aldosteronism (PA) patients, employing ambulatory blood pressure monitoring (ABPM) for comparative analysis with individuals diagnosed with essential hypertension (EH). The study reveals that PA patients exhibited significantly elevated levels of cystatin C and urine microalbumin/creatinine ratio (UACR). Additionally, a higher prevalence of non-dipping blood pressure patterns in PA patients suggests an increased risk of circadian blood pressure regulation disturbances. Notably, while most BPV indices were comparable between the two groups, the standard deviation of 24-h weighted diastolic blood pressure was markedly lower in the PA cohort, distinguishing it as a unique variable. Through multiple linear regression analysis, the duration of hypertension, angiotensin II concentrations, and daytime systolic blood pressure standard deviation emerged as significant determinants of estimated glomerular filtration rate (eGFR) in PA patients. Furthermore, UACR was significantly influenced by variables including the 24-h weighted standard deviation (wSD) of systolic BP, glycosylated hemoglobin levels, nocturnal systolic BP peaks, aldosterone-renin ratio (ARR), and total cholesterol, with the most pronounced association observed with the 24-h wSD of systolic BP (β = 0.383).The study also found significant correlations between the 24-h wSD of systolic BP, ARR, HbA1c, serum potassium levels, and 24-h urinary microalbumin, underscoring the critical role of the 24-h wSD of systolic BP (β = 0.267). These findings underscore the imperative of an integrated management strategy for PA, addressing the intricate interconnections among metabolic abnormalities, blood pressure variability, and renal health outcomes.

Assessing bias in GFR estimating equations: improper GFR stratification can yield misleading results

BACKGROUND

Assessing bias (estimated - measured) is key to evaluating glomerular filtration rate (GFR). Stratification by subgroups can indicate where equations perform differently. However, there is a fallacy in the assessment of two instruments (e.g., eGFR and mGFR) when stratifying on the level of only one of those instruments. Here, we present statistical aspects of the problem and a solution for GFR stratification along with an empirical investigation using data from the CKiD study.

METHODS

Compared and contrasted biases (eGFR relative to mGFR) with 95% confidence intervals within strata of mGFR only, eGFR only, and the average of mGFR and eGFR using data from the Chronic Kidney Disease in Children (CKiD) study.

RESULTS

A total of 304 participants contributed 843 GFR studies with a mean mGFR of 48.46 (SD = 22.72) and mean eGFR of 48.67 (SD = 22.32) and correlation of 0.904. Despite strong agreement, eGFR significantly overestimated mGFR when mGFR < 30 (+ 6.2%; 95%CI + 2.9%, + 9.7%) and significantly underestimated when mGFR > 90 (-12.2%; 95%CI - 17.3%, - 7.0%). Significant biases in opposite direction were present when stratifying by eGFR only. In contrast, when stratifying by the average of eGFR and mGFR, biases were not significant (+ 1.3% and - 1.0%, respectively) congruent with strong agreement.

CONCLUSIONS

Stratifying by either mGFR or eGFR only to assess eGFR biases is ubiquitous but can lead to inappropriate inference due to intrinsic statistical issues that we characterize and empirically illustrate using data from the CKiD study. Using the average of eGFR and mGFR is recommended for valid inferences in evaluations of eGFR biases.

Prognostic Assessment of Histopathologic Lesions in Patients with Community-Acquired AKI with Biopsy-Proven Acute Tubular Necrosis

Key Points

Background

Community-acquired AKI (CA-AKI) was more likely to be comorbid with underlying kidney histopathological lesions in addition to acute tubular necrosis (ATN). Thus, we tried to clarify the histological determinants that could influence the prognosis and recovery of patients with CA-AKI with biopsy-proven ATN.

Methods

Adult patients with CA-AKI with biopsy-proven ATN who underwent renal biopsy at Shanghai Changzheng Hospital from January 1, 2010, to December 31, 2018, were included and followed up for 5 years. The impacts of histopathological lesions on short-term and long-term renal dysfunction were also analyzed.

Results

Multivariate analysis revealed that ATNs, crescents, and decrease of arteriole lumens increased short-term dialysis requirements. The severity of ATN was closely associated with renal survival. According to the Kaplan–Meier analysis, the severity of ATN was significantly associated with short-term dialysis needs and long-term development of ESKD during follow-up. Crescent and decrease of arteriole lumens are significantly associated with progression to ESKD and exert synergistic effects with ATN. For patients who did not progress to dialysis, tubular atrophic/interstitial fibrosis and endocapillary lesions were more relevant to partial recovery of renal function after CA-AKI at the 3-month follow-up and increased the risk of CKD stage 3–5 at the 5-year follow-up. According to our correlation analysis, endocapillary lesions and crescents were positively correlated with ATN.

Conclusions

Histopathologic lesions, apart from tubular necrosis, contributed to the detrimental short-term and long-term renal prognosis of patients with CA-AKI with ATN; concomitant histopathologic lesions exerted a combined impact on renal survival together with ATN in patients with CA-AKI.

CD226 promotes renal fibrosis by regulating macrophage activation and migration

It has been found that CD226 plays an important role in regulating macrophage function, but its expression and function in macrophages during renal fibrogenesis have not been studied. Our data demonstrated that CD226 expression in macrophages was obviously upregulated in the unilateral ureteral obstruction model, while CD226 deficiency attenuated collagen deposition in renal interstitium along with fewer M1 within renal cortex and renal medulla and a lower level of proinflammatory factors compared to that of control littermates. Further studies demonstrated that Cd226-/- bone marrow-derived macrophages transferring could significantly reduce the tubular injury, collagen deposition, and proinflammatory cytokine secretion compared with that of Cd226+/+ bone marrow-derived macrophages transferring in the unilateral ureteral obstruction model. Mechanistic investigations revealed that CD226 promoted proinflammatory M1 macrophage accumulation in the kidney via suppressing KLF4 expression in macrophages. Therefore, our results uncovered a pathogenic role of CD226 during the development of chronic kidney disease by promoting monocyte infiltration from peripheral blood into the kidney and enhancing macrophage activation toward the inflammatory phenotype by suppressing KLF4 expression.

Association between stress hyperglycemia ratio and in-hospital outcomes: findings from the improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome (CCC-ACS) Project

BACKGROUND

Stress hyperglycemia ratio (SHR) could provide accurate information on the acute status of hyperglycemia. The relationship between SHR and acute coronary syndrome (ACS) prognosis remains unclear. This study was conducted to identity the association between SHR and in-hospital outcomes in patients with ACS.

METHODS

A total of 12,010 patients were eventually enrolled in the study. The relationship between SHR and in-hospital major adverse cardiovascular events (MACEs) was then modeled by restricted cubic spline (RCS) curves, and all patients were divided into three groups according to the results. The multivariate logistic regression analysis was used to determine the associations between the SHR and in-hospital outcomes, described as odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses were also performed on different diseases.

RESULTS

The median age of this cohort was 63 (54, 71) years old, and 8942 (74.5%) were male. Group 1 was defined as SHR < 0.6 (n = 426), Group 2 was defined as SHR between 0.6 and 1 (n = 5821), and Group 3 was defined as SHR > 1 (n = 5763). Compared with Group 2, Group 1 (OR = 1.891, 95% CI: 1.028-3.479, P < 0.001) and Group 3 (OR = 1.868, 95% CI: 1.434-2.434, P < 0.001) had higher risks of suffering from in-hospital MACEs. SHR was associated with higher risks of in-hospital MACEs in the subgroups of DM [OR = 2.282, 95% CI: 1.477-3.524).

CONCLUSIONS

Both low and high SHR levels were independently associated with in-hospital MACEs. Young males with DM, hypertension, and decreased renal function had much higher risks of suffering from SHR-correlated MACEs.

Risk factor analysis for a rapid progression of chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is a growing global health concern. Identifying individuals in routine clinical care with new-onset CKD at high risk of rapid progression of the disease is imperative to guide allocation of prophylactic interventions, but community-based data are limited. We aimed to examine the risk of rapid progression, kidney failure, hospitalization and death among adults with incident CKD stage G3 and to clarify the association between predefined risk markers and rapid CKD progression.

METHODS

Using plasma creatinine measurements for the entire Danish population from both hospitals and primary care, we conducted a nationwide, population-based cohort study, including adults in Denmark with incident CKD stage G3 in 2017-2020. We estimated 3-year risks of rapid progression (defined by a confirmed decline in estimated glomerular filtration rate of ≥5 mL/min/1.73 m2/year), kidney failure, all-cause hospitalization and death. To examine risk markers, we constructed a heat map showing the risk of rapid progression based on predefined markers: albuminuria, sex, diabetes and hypertension/cardiovascular disease.

RESULTS

Among 133 443 individuals with incident CKD stage G3, the 3-year risk of rapid progression was 14.6% [95% confidence interval (CI) 14.4-14.8]. The 3-year risks of kidney failure, hospitalization and death were 0.3% (95% CI 0.3-0.4), 53.3% (95% CI 53.0-53.6) and 18.1% (95% CI 17.9-18.4), respectively. In the heat map, the 3-year risk of rapid progression ranged from 7% in females without albuminuria, hypertension/cardiovascular disease or diabetes, to 46%-47% in males and females with severe albuminuria, diabetes and hypertension/cardiovascular disease.

CONCLUSION

This population-based study shows that CKD stage G3 is associated with considerable morbidity in a community-based setting and underscores the need for optimized prophylactic interventions among such patients. Moreover, our data highlight the potential of using easily accessible markers in routine clinical care to identify individuals who are at high risk of rapid progression.

Cumulative exposure to AHA Life's Essential 8 is associated with nonalcoholic fatty liver disease: a large cohort study

BACKGROUND AND AIM

We aimed to explore the associations of baseline and cumulative cardiovascular health with nonalcoholic fatty liver disease (NAFLD) development and regression using the new Life's Essential 8 score.

METHODS

From a health screening database, participants who underwent at least 4 health examinations between 2012 and 2022 were recruited and categorized into two cohorts: (a) the NAFLD development cohort with no history of NAFLD prior to Exam 4 and (b) the NAFLD regression cohort with diagnosed NAFLD prior to Exam 4. The LE8 score was calculated from each component. The outcomes were defined as newly incident NAFLD or regression of existing NAFLD from Exam 4 to the end of follow-up.

RESULTS

In the NAFLD development cohort, of 21,844 participants, 3,510 experienced incident NAFLD over a median follow-up of 2.3 years. Compared with the lowest quartile of cumulative LE8, individuals in the highest quartile conferred statistically significant 76% lower odds (hazard ratio [HR] 0.24, 95% confidence interval [CI], 0.21-0.28) of NAFLD incidence, and corresponding values for baseline LE8 were 42% (HR 0.58, 95% CI 0.53-0.65). In the NAFLD regression cohort, of 6,566 participants, 469 experienced NAFLD regression over a median follow-up of 2.4 years. Subjects with the highest quartile of cumulative LE8 had 2.03-fold (95% CI, 1.51-2.74) higher odds of NAFLD regression, and corresponding values for baseline LE8 were 1.61-fold (95% CI, 1.24-2.10).

CONCLUSION

Cumulative ideal cardiovascular health exposure is associated with reduced NAFLD development and increased NAFLD regression. Improving and preserving health behaviors and factors should be emphasized as an important part of NAFLD prevention and intervention strategies.

Gonadal hormones and metabolic syndrome in middle-aged and elderly males: results from a prospective cohort study in China

Background

Research has shown that gonadal hormones are involved in metabolic pathways relevant to metabolic syndrome (MetS). Nevertheless, no longitudinal study has been conducted on the association between SHBG and MetS in Chinese. The objective of our study was to determine whether there is any association between middle-aged and elderly males in China.

Methods

A total of 531 eligible male subjects, aged above 40 years or older, without MetS at baseline, were recruited. Sex hormone binding globulin (SHBG), total testosterone (TT), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were measured. A harmonized definition and recommended thresholds for the Chinese population were used to determine metabolic syndrome.

Results

During 3.2 years of follow-up, 20.7% of subjects had developed MetS. Compared with the non-MetS group, subjects in the new-onset MetS group had significantly lower SHBG (43.5 nmol/L [28.8, 74.9] vs 53.7nmol/L [33.8, 115.0], P=0.0018), TT (18.1nmol/L [13.6-21.7] vs 19.5nmol/L[15.0-23.6], P=0.0204), and LH (5.13mIU/L [3.63-7.29] vs 5.87mIU/L [4.05-8.36]) at baseline. The incidence of MetS was decreased according to elevated SHBG quartiles (Q1:26.9%, Q2:22.7%, Q3:21.1%, Q4:12.1%, P for trend =0.0035), TT (Q1: 25.2%, Q2:23.7%, Q3: 17.3%, Q4: 16.7%, P for trend=0.0425), and LH (Q1:25.0%, Q2:21.8%, Q3: 21.8%, Q4: 14.3%, P for trend=0.0411). Compared with those in quartile 4, the OR[CI] of incident MetS for participants in Quartile 1 was 2.33[1.13-4.79] after multiple adjustments. But associations between incident MetS and different quartiles of LH, TT, and FSH were not observed after multiple adjustments. In the subgroup analyses, the significant association between SHBG level and Mets was detected in subjects over 60 years or older, with normal BMI, without insulin resistance, and with eGFR ≥90 mL/min per 1.73m2.

Conclusion

Compared with TT, LH, and FSH, a lower level of SHBG is significantly related to the incidence of MetS among middle-aged and elderly males in China.

Exploring Health Literacy and Vascular Access Decision Making: A Scoping Review

One in seven adults in the United States has chronic kidney disease (CKD) and individuals with the most severe form, end stage kidney disease (ESKD), may require renal replacement therapy with hemodialysis. Despite well-established guidelines indicating that arteriovenous access is the preferred type of vascular access for hemodialysis, in 2021, 85.4% of patients initiated dialysis with a CVC. While the reasons for this evidence-practice gap are unclear, health literacy and patient disease-specific knowledge may play an important role. Importantly, 25% of patients with CKD have limited health literacy. While there is an abundance of research regarding the presence of poor health literacy, poor kidney disease-specific knowledge, and their association with health outcomes in patients with CKD, there is currently a paucity of data about the relationship between health literacy, vascular access-specific knowledge, and vascular access outcomes. The aim of this narrative review is to describe the relationship between health literacy, disease-specific knowledge, and vascular access in patients with CKD. A better understanding of health literacy in this population will help inform the development of strategies to assess patient vascular access-specific knowledge and aid in vascular access decision making.

Age and estimated glomerular filtration rate in Chinese older adults: a cohort study from 2014 to 2020

Objectives

This study aimed to fill the data gap of the course of renal function decline in old age and explore changes in renal function across different health states with increasing age.

Methods

This observational, retrospective, single-center cohort study included 5,112 Chinese older adults (3,321 men and 1,791 women, range 60-104 years). The individual rate of estimated glomerular filtration rate (eGFR) decline was analyzed using linear mixed-effects model to account for repeated measures over the years.

Results

The median age was 66 years, median BMI was 24.56 kg/m2, and median eGFR was 89.86 mL/min.1.73 m2. For every 1-year increase in age, women's eGFR decreased by 1.06 mL/min/1.73 m2 and men's by 0.91 mL/min/1.73 m2. We observed greater age-related eGFR decline in men and women with high systolic blood pressure (SBP). Men with high triglyceride (TG), high low-density lipoprotein cholesterol (LDL-C), and low high-density lipoprotein cholesterol (HDL-C), had greater age-related eGFR decline. In women, different BMI groups showed significant differences in age-related eGFR decline, with the highest decline in those with obesity. Additionally, participants with normal baseline eGFR had a faster age-related decline than those with low baseline eGFR.

Conclusion

The eGFR declined linearly with age in Chinese older adults, with women exhibiting a slightly faster decline than men. Both men and women should be cautious of SBP. Older adults with normal baseline renal function experienced a faster eGFR decline. Men with high TG, LDL-C, and low HDL-C levels, as well as obese women, should be vigilant in monitoring renal function.

Renal involvement in adults with cystic fibrosis: study of 89 patients

INTRODUCTION

We are assisting to an increase in survival rates among individuals with cystic fibrosis (CF). Until now, renal involvement was a minority issue, but with the rise in life expectancy, we will likely see an increase in its prevalence. Our main objective was to assess renal function in CF and study risk factors associated with its deterioration.

METHODS

A cross-sectional, retrospective study was conducted, including adults with CF. Clinical, respiratory function, microbiological, blood and urine analysis, and major chronic treatments received were collected.

RESULTS

Eighty nine patients with a mean age of 35±12 years were analyzed. Mean serum creatinine levels were 0.8±0.2mg/dL. 10.6% had a glomerular filtration rate less than 90mL/min/1.73m2. No patient showed albuminuria. In multivariate model, only age was an independent risk factor for reduced glomerular filtration (OR: 0.344; 95%CI: 0.004-0.017; P=.002).

CONCLUSIONS

11% of CF adults show decreased glomerular filtration, with age being the sole independent risk factor. Vigilance for this uncommon condition is crucial.

Replacement Strategies for Tunneled Hemodialysis Catheters with Complications: A Nationwide Cohort Study

Key Points

Background

Tunneled hemodialysis catheters often have infectious or mechanical complications that require unplanned removal and replacement, but the optimal replacement strategy is unknown. This study described the real-world use of two strategies in Australia and compared the survival of replacement catheters inserted by either strategy.

Methods

Observational data from the REDUcing the burden of dialysis Catheter ComplicaTIOns: a National approach trial, which enrolled a nationwide cohort of 6400 adults who received an incident hemodialysis catheter (2016–2020), was used for this secondary analysis. Tunneled catheters were replaced by either catheter exchange through the existing tunnel tract or removal and replacement through a new tract. The effect of the replacement strategy on the time to catheter removal because of infection or dysfunction was estimated by emulating a hypothetical pragmatic randomized trial among a subset of 434 patients with mechanical tunneled catheter failure.

Results

Of 9974 tunneled hemodialysis catheters inserted during the trial, 380 had infectious and 945 had mechanical complications that required replacement. Almost all infected hemodialysis catheters (97%) were removed and separately replaced through a new tunnel tract, whereas nephrology services differed widely in their replacement practices for catheters with mechanical failure (median=50% guidewire exchanged, interquartile range=30%–67%). Service-level differences accounted for 29% of the residual variation after adjusting for patient factors. In the target trial emulation cohort of patients with mechanical catheter failure (n=434 patients), catheter exchange was not associated with lower complication-free survival at 1, 6, or 12 months (counterfactual survival difference at 1 month=5.9%; 95% confidence interval, −2% to 14%).

Conclusions

Guidewire exchange for mechanical failure of catheter was not associated with lower catheter survival and may be preferable for patients.

Trial registration and protocol:

The trial was registered in the Australia and New Zealand clinical trials registry on the June 23, 2016 (ACTRN12616000830493).

Hepatitis B virus infection as a risk factor for chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Currently, several studies have observed that chronic hepatitis B virus infection is associated with the pathogenesis of kidney disease. However, the extent of the correlation between hepatitis B virus infection and the chronic kidney disease risk remains controversial.

METHODS

In the present study, we searched all eligible literature in seven databases in English and Chinese. The random effects model was used to conduct a meta-analysis. Quality of included studies was assessed using the Newcastle-Ottawa Quality Scale.

RESULTS

In this analysis, a total of 31 studies reporting the association between hepatitis B virus infection and chronic kidney disease risk were included. The results showed a significant positive association between hepatitis B virus infection and the risk of chronic kidney disease (pooled OR, 1.20; 95% CI, 1.12-1.29), which means that hepatitis B virus increases the risk of developing chronic kidney disease.

CONCLUSION

This study found that hepatitis B virus infection was associated with a significantly increased risk of chronic kidney disease. However, the current study still cannot directly determine this causal relationship. Thus, more comprehensive prospective longitudinal studies are needed in the future to provide further exploration and explanation of the association between hepatitis B virus and the risk of developing chronic kidney disease.

Evaluation of health care utilisation and mortality in medical hospitalisations with multimorbidity and kidney disease, according to frailty: a nationwide cohort study

INTRODUCTION

The impact of impaired kidney function on healthcare use among medical hospitalisations with multimorbidity and frailty is incompletely understood. In this study, we assessed the prevalence of acute kidney injury (AKI) and chronic kidney disease (CKD) among multimorbid medical hospitalisations in Switzerland and explored the associations of kidney disease with in-hospital outcomes across different frailty strata.

METHODS

This observational study analysed nationwide hospitalisation records from 1 January 2012 to 31 December 2020. We included adults (age ≥18 years) with underlying multimorbidity hospitalised in a medical ward. The study population consisted of hospitalisations with AKI, CKD or no kidney disease (reference group), and was stratified by three frailty levels (non-frail, pre-frail, frail). Main outcomes were in-hospital mortality, intensive care unit (ICU) treatment, length of stay (LOS) and all-cause 30-day readmission. We estimated multivariable adjusted odds ratios (OR) and changes in percentage of log-transformed continuous outcomes with 95% confidence intervals (CI).

RESULTS

Among 2,651,501 medical hospitalisations with multimorbidity, 198,870 had a diagnosis of AKI (7.5%), 452,990 a diagnosis of CKD (17.1%) and 1,999,641 (75.4%) no kidney disease. For the reference group, the risk of in-hospital mortality was 4.4%, for the AKI group 14.4% (adjusted odds ratio [aOR] 2.56 [95% CI 2.52-2.61]) and for the CKD group 5.9% (aOR 0.98 [95% CI 0.96-0.99]), while prevalence of ICU treatment was, respectively, 10.5%, 21.8% (aOR 2.39 [95% CI 2.36-2.43]) and 9.3% (aOR 1.01 [95% CI 1.00-1.02]). Median LOS was 5 days (interquartile range [IQR] 2.0-9.0) in hospitalisations without kidney disease, 9 days (IQR 5.0-15.0) (adjusted change [%] 67.13% [95% CI 66.18-68.08%]) in those with AKI and 7 days (IQR 4.0-12.0) (adjusted change [%] 18.94% [95% CI 18.52-19.36%]) in those with CKD. The prevalence of 30-day readmission was, respectively, 13.3%, 13.7% (aOR 1.21 [95% CI 1.19-1.23]) and 14.8% (aOR 1.26 [95% CI 1.25-1.28]). In general, the frequency of adverse outcomes increased with the severity of frailty.

CONCLUSION

In medical hospitalisations with multimorbidity, the presence of AKI or CKD was associated with substantial additional hospitalisations and healthcare utilisation across all frailty strata. This information is of major importance for cost estimates and should stimulate discussion on reimbursement.

Estimating the global prevalence of secondary hyperparathyroidism in patients with chronic kidney disease

Background

Chronic kidney disease (CKD)-related secondary hyperparathyroidism (SHPT) is associated with higher morbidity and death. The goal of this study was to mine the SHPT data already available to do a meta-analysis on the global prevalence of SHPT caused by CKD.

Methods

Embase, Medline, Web of Science, Cochrane Central Databases, and Google Scholar were searched to identify studies on the prevalence of SHPT due to CKD from inception to November 2023. Pooled prevalence was calculated using the DerSimonian-Laird random effects model with a logit transformation.

Results

Twenty-one eligible studies involving 110977 patients were included. Our results revealed that the estimated global prevalence of SHPT due to CKD was 49.5% (95% CI 30.20-68.18), regardless of the diagnostic criteria. For subgroup analysis, Southern Asia (84.36%, 95% CI 79.35-88.34) had a significantly higher SHPT prevalence than other geographic regions. SHPT due to CKD was most prevalent in China (85.14%, 95% CI 81.74-88.00).

Conclusions

SHPT due to CKD is highly prevalent. This necessitates awareness and therapeutic approaches from primary care physicians, medical professionals, and health strategy authorities.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO, identifier CRD42024514007.

Potentials of Natural Antioxidants in Reducing Inflammation and Oxidative Stress in Chronic Kidney Disease

Chronic kidney disease (CKD) presents a substantial global public health challenge, with high morbidity and mortality. CKD patients often experience dyslipidaemia and poor glycaemic control, further exacerbating inflammation and oxidative stress in the kidney. If left untreated, these metabolic symptoms can progress to end-stage renal disease, necessitating long-term dialysis or kidney transplantation. Alleviating inflammation responses has become the standard approach in CKD management. Medications such as statins, metformin, and GLP-1 agonists, initially developed for treating metabolic dysregulation, demonstrate promising renal therapeutic benefits. The rising popularity of herbal remedies and supplements, perceived as natural antioxidants, has spurred investigations into their potential efficacy. Notably, lactoferrin, Boerhaavia diffusa, Amauroderma rugosum, and Ganoderma lucidum are known for their anti-inflammatory and antioxidant properties and may support kidney function preservation. However, the mechanisms underlying the effectiveness of Western medications and herbal remedies in alleviating inflammation and oxidative stress occurring in renal dysfunction are not completely known. This review aims to provide a comprehensive overview of CKD treatment strategies and renal function preservation and critically discusses the existing literature's limitations whilst offering insight into the potential antioxidant effects of these interventions. This could provide a useful guide for future clinical trials and facilitate the development of effective treatment strategies for kidney functions.

Assessing renal interstitial fibrosis using compartmental, non-compartmental, and model-free diffusion MRI approaches

OBJECTIVE

To assess renal interstitial fibrosis (IF) using diffusion MRI approaches, and explore whether corticomedullary difference (CMD) of diffusion parameters, combination among MRI parameters, or combination with estimated glomerular filtration rate (eGFR) benefit IF evaluation.

METHODS

Forty-two patients with chronic kidney disease were included, undergoing MRI examinations. MRI parameters from apparent diffusion coefficient (ADC), intra-voxel incoherent motion (IVIM), diffusion kurtosis imaging (DKI), and diffusion-relaxation correlated spectrum imaging (DR-CSI) were obtained both for renal cortex and medulla. CMD of these parameters was calculated. Pathological IF scores (1-3) were obtained by biopsy. Patients were divided into mild (IF = 1, n = 23) and moderate-severe fibrosis (IF = 2-3, n = 19) groups. Group comparisons for MRI parameters were performed. Diagnostic performances were assessed by the receiver operator's curve analysis for discriminating mild from moderate-severe IF patients.

RESULTS

Significant inter-group differences existed for cortical ADC, IVIM-D, IVIM-f, DKI-MD, DR-CSI VB, and DR-CSI VC. Significant inter-group differences existed in ΔADC, ΔMD, ΔVB, ΔVC, ΔQB, and ΔQC. Among the cortical MRI parameters, VB displayed the highest AUC = 0.849, while ADC, f, and MD also showed AUC > 0.8. After combining cortical value and CMD, the diagnostic performances of the MRI parameters were slightly improved except for IVIM-D. Combining VB with f brings the best performance (AUC = 0.903) among MRI bi-variant models. A combination of cortical VB, ΔADC, and eGFR brought obvious improvement in diagnostic performance (AUC 0.963 vs 0.879, specificity 0.826 vs 0.896, and sensitivity 1.000 vs 0.842) than eGFR alone.

CONCLUSION

Our study shows promising results for the assessment of renal IF using diffusion MRI approaches.

CRITICAL RELEVANCE STATEMENT

Our study explores the non-invasive assessment of renal IF, an independent and effective predictor of renal outcomes, by comparing and combining diffusion MRI approaches including compartmental, non-compartmental, and model-free approaches.

KEY POINTS

Significant difference exists for diffusion parameters between mild and moderate-severe IF. Generally, cortical parameters show better performance than corresponding CMD. Bi-variant model lifts the diagnostic performance for assessing IF.

Five-year survival analysis and predictors of mortality of adult hemodialysis patients in Indonesia: a nationwide database analysis

BACKGROUND

Hemodialysis (HD) is the modality of renal replacement therapy (RRT) with the highest mortality rate. The identification of prognostic factors will help achieve better outcomes among HD patients. In this study, we sought to conduct a survival analysis and determine the predictors of mortality among adult Indonesian HD patients using data obtained from Indonesian Renal Registry (IRR).

METHODS

This is a retrospective cohort study which reviewed all adult hemodialysis patients in Indonesia based on the records of IRR during 2007-2022. Variables analyzed in this study include age, sex, etiology of CKD, cause of death, HD frequency, and initial vascular access. A 5-year follow-up was performed until the outcome of death or drop out was found.

RESULTS

Among 99,552 eligible patients, the mean survival length was 1536.21 ± 2.50 days. The 5-year survival rate was 77%. Cox proportional hazard regression model revealed demographic and clinical characteristics that are significantly associated with mortality: male sex (HR: 1.038, 95% CI 1.002-1.075), age of 60 years or older (HR: 1.329, 95% CI 1.281-1.379), diabetic nephropathy (HR: 1.347, 95% CI 1.249-1.452), twice-weekly hemodialysis frequency (HR: 1.080, 95% CI 1.011-1.155), initial vascular accesses with femoral vein puncture (HR: 2.710, 95% CI 2.568-2.860), and CVC (HR: 2.992, 95% CI 2.848-3.144).

CONCLUSIONS

The 5-year survival rate of Indonesian HD patients is 77. Male sex, age of HD onset at 60 years or older, diabetic nephropathy, twice-weekly HD frequency, and the initial vascular accesses with femoral vein puncture and CVC are associated with increased risk of mortality.

Assessment of the safety of Roxadustat for cardiovascular events in chronic kidney disease-related anemia using meta-analysis and bioinformatics

Objective

This study compares the cardiovascular risk in anemic chronic kidney disease patients treated with Roxadustat versus erythropoietin stimulating agents (ESAs). It also explores the cardiovascular impact of Roxadustat.

Methods

We searched PubMed, EMBASE, Cochrane, Scopus, and Web of Science databases up to 13 August 2023, using terms such as "ESA," "Roxadustat," "MACE," "stroke," "death," "myocardial infarction," and "heart failure." Two researchers independently selected and extracted data based on predefined criteria. We assessed the risk of bias with the Cochrane tool and analyzed statistical heterogeneity using the Q and I2 tests. We conducted subgroup analyses by geographical region and performed data analysis with Stata 14.0 and RevMan 5.4 software. Data were sourced from the NCBI database by filtering for "Roxadustat" and "human," and differentially expressed genes were identified using R software, setting the significance at p < 0.01 and a 2-fold logFC, followed by GO enrichment analysis, KEGG pathway analysis, and protein interaction network analysis.

Results

A total of 15 articles encompassing 1,43,065 patients were analyzed, including 1,38,739 patients treated with ESA and 4,326 patients treated with Roxadustat. In the overall population meta-analysis, the incidences of Major Adverse Cardiovascular Events (MACE), death, and heart failure (HF) were 13%, 8%, and 4% in the Roxadustat group, compared to 17%, 12%, and 6% in the ESA group, respectively, with P-values greater than 0.05. In the subgroup analysis, the incidences were 13%, 11%, and 4% for the Roxadustat group versus 17%, 15%, and 5% for the ESA group, also with p-values greater than 0.05. Bioinformatics analysis identified 59 differentially expressed genes, mainly involved in the inflammatory response. GO enrichment analysis revealed that these genes are primarily related to integrin binding. The main pathways identified were the TNF signaling pathway, NF-κB signaling pathway, and lipid metabolism related to atherosclerosis. The protein interaction network highlighted IL1B, CXCL8, ICAM1, CCL2, and CCL5 as the top five significantly different genes, all involved in the inflammatory response and downregulated by Roxadustat, suggesting a potential role in reducing inflammation.

Conclusion

The meta-analysis suggests that the use of Roxadustat and ESA in treating anemia associated with chronic kidney disease does not significantly alter the likelihood of cardiovascular events in the overall and American populations. However, Roxadustat exhibited a safer profile with respect to MACE, death, and heart failure. The bioinformatics findings suggest that Roxadustat may influence integrin adhesion and affect the TNF and NF-κB signaling pathways, along with lipid and atherosclerosis pathways, potentially reducing inflammation.

Pulmonary hypertension and chronic kidney disease: prevalence, pathophysiology and outcomes

Pulmonary hypertension (PH) is common in patients with chronic kidney disease (CKD) or kidney failure, with an estimated prevalence of up to 78% in those referred for right-heart catheterization. PH is independently associated with adverse outcomes in CKD, raising the possibility that early detection and appropriate management of PH might improve outcomes in at-risk patients. Among patients with PH, the prevalence of CKD stages 3 and 4 is estimated to be as high as 36%, and CKD is also independently associated with adverse outcomes. However, the complex, heterogenous pathophysiology and clinical profile of CKD-PH requires further characterization. CKD is often associated with elevated left ventricular filling pressure and volume overload, which presumably leads to pulmonary vascular stiffening and post-capillary PH. By contrast, a distinct subgroup of patients at high risk is characterized by elevated pulmonary vascular resistance and right ventricular dysfunction in the absence of pulmonary venous hypertension, which may represent a right-sided cardiorenal syndrome defined in principle by hypervolaemia, salt avidity, low cardiac output and normal left ventricular function. Current understanding of CKD-PH is limited, despite its potentially important ramifications for clinical decision making. In particular, whether PH should be considered when determining the suitability and timing of kidney replacement therapy or kidney transplantation is unclear. More research is urgently needed to address these knowledge gaps and improve the outcomes of patients with or at risk of CKD-PH.

Long-Term Experience of Arterio-Venous Fistula Surgery in Children on Hemodialysis

Background: Arterio-venous fistulas (AVF) are used as first-line access for hemodialysis (HD) in the pediatric population. The aim of this investigation was to describe a single-center experience in the creation of AVF, together with its patency in children. Methods: This single-center retrospective study included all patients aged ≤18 years with AVFs created between 1993 and 2023. The collected data included patients' demographics, hemodialysis history, intraoperative data, and required reinterventions in order to determine the impact of these variables on primary, primary-assisted, and secondary patency. Results: Fifty-seven patients were analyzed with a median age of 15 years (range, 7-18 years). Fifty-four forearm and four upper arm fistulas were performed. The median follow-up was 6.9 years (range, 0-23 years). The primary failure rate was 10.5%. The primary patency rate was 67.6%, 53.6%, 51.4%, and 38.1% after 1, 3, 5, and 10 years; primary-assisted patency was 72.9%, 62.8%, 60.6%, and 41.5%; and secondary patency was 87.3%, 81.3%, 76.8%, and 66.6% after 1, 3, 5, and 10 years in the studied population. Conclusions: AVFs showed an acceptable rate of primary failure and excellent long-term patency. In this context, AVFs are an appropriate option for HD access, especially in pediatric patients.

Association of random glucose to albumin ratio with post-contrast acute kidney injury and clinical outcomes in patients with ST-elevation myocardial infarction

Purpose

Both glucose and albumin are associated with chronic inflammation, which plays a vital role in post-contrast acute kidney injury (PC-AKI). To explore the relationship between random glucose to albumin ratio (RAR) and the incidence of PC-AKI after percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI).

Patients and methods

STEMI patients who underwent PCI were consecutively enrolled from January, 01, 2010 to February, 28, 2020. All patients were categorized into T1, T2, and T3 groups, respectively, based on RAR value (RAR < 3.377; 3.377 ≤ RAR ≤ 4.579; RAR > 4.579). The primary outcome was the incidence of PC-AKI, and the incidence of major adverse clinical events (MACE) was the second endpoint. The association between RAR and PC-AKI was assessed by multivariable logistic regression analysis.

Results

A total of 2,924 patients with STEMI undergoing PCI were finally included. The incidence of PC-AKI increased with the increasing tertile of RAR (3.2% vs 4.8% vs 10.6%, P<0.001). Multivariable regression analysis demonstrated that RAR (as a continuous variable) was associated with the incidence of PC-AKI (adjusted odds ratio (OR) =1.10, 95% confidence interval (CI) =1.04 - 1.16, P<0.001) and in-hospital MACE (OR=1.07, 95% CI=1.02 - 1.14, P=0.012); RAR, as a categorical variable, was significantly associated with PC-AKI (T3 vs. T1, OR=1.70, 95% CI=1.08 - 2.67, P=0.021) and in-hospital MACE (T3 vs. T1, OR=1.63, 95% CI=1.02 - 2.60, P=0.041) in multivariable regression analyses. Receiver operating characteristic curve analysis showed that RAR exhibited a predictive value for PC-AKI (area under the curve (AUC)=0.666, 95% CI=0.625 - 0.708), and in-hospital MACE (AUC= 0.662, 95% CI =0.619 - 0.706).

Conclusions

The high value of RAR was significantly associated with the increasing risk of PC-AKI and in-hospital MACE after PCI in STEMI patients, and RAR offers a good predictive value for those outcomes.

Prevalence, Predictors, and Outcomes of Pulmonary Hypertension in Patients with Lupus Nephritis

Background and Objectives: This study aimed to assess the prevalence, predictors, and outcomes of pulmonary hypertension (PH) in patients with lupus nephritis (LN). Materials and Methods: Baseline characteristics and clinical outcomes of 387 patients with LN were retrospectively collected from 2007 to 2017. PH was defined as pulmonary artery systolic pressure ≥40 mmHg assessed by resting transthoracic echocardiography. The primary endpoint was all-cause mortality. The secondary endpoint was renal events, defined as the doubling of baseline serum creatinine or end-stage renal disease. Associations between PH and outcomes were analyzed by Cox regression models. Results: A total of 15.3% (59/387) of patients with LN were diagnosed with PH, and the prevalence of PH was higher for patients with an estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m2 compared to those with an eGFR ≥ 30 mL/min/1.73 m2 (31.5% vs. 12.6%). Higher mean arterial pressure, lower hemoglobin, and lower triglyceride levels were associated with greater odds of having PH. After adjusting for relevant confounding variables, PH was independently associated with a higher risk for death (HR: 2.01; 95% CI: 1.01-4.00; p = 0.047) and renal events (HR: 2.07; 95% CI: 1.04-4.12; p = 0.039). Conclusions: PH is an independent risk factor for all-cause mortality and adverse renal outcomes in patients with LN.

Associations of accelerometer-measured physical activity and sedentary time with renal function and chronic kidney disease: a national population-based study

Introduction

There is limited information about the relationship between physical activity (PA) and sedentary behaviors in chronic kidney disease (CKD). Therefore, this study aims to explore the associations of accelerometer-measured PA and sedentary behaviors with CKD.

Methods

A cross-sectional study was conducted using data from the National Health and Nutrition Examination Survey in the 2003-2004 and 2005-2006 survey cycles. A uniaxial accelerometer measured physical activity (PA) and sedentary time (ST). The associations of PA and ST with estimated glomerular filtration rate (eGFR) and odds of CKD adopted the generalized linear regression, multivariable logistic regression, and isotemporal substitution models.

Results

A total of 5,990 adults with 605 CKD patients were included in this study. Compared with the individuals in the first quartile group, participants in the fourth quartile of low-intensity physical activity (LIPA), moderate to vigorous physical activity (MVPA), and ST were associated with 52% (35%, 65%) and 42% (14%, 62%) lower odds of CKD and 64% (17%, 131%) higher odds of CKD, respectively. Substituting 30 min/day of ST with equivalent LIPA/MVPA contributed to risk reduction in CKD.

Discussion

The findings suggest that increased LIPA and MVPA and reduced ST were associated with a lower risk of CKD and that replacing ST with LIPA may decrease the risk of CKD.

Association of serum concentrations of remnant cholesterol with incident cardiovascular disease in patients with rheumatoid arthritis: A real-world data from 2001 to 2022

BACKGROUND

Remnant cholesterol (RC) promotes cardiovascular disease (CVD) in the general population, but its role among rheumatoid arthritis (RA) patients remains unknown. We aimed to investigate circulating RC levels associated with incident CVD among Chinese patients with RA.

METHODS

A total of 1018 RA patients free of baseline CVD were included and followed up in a prospective RA CVD cohort from 2001 to 2022. Fasting serum levels of triglycerides, total cholesterol (TC), low-density (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were measured, while RC and Non-HDL-C levels were calculated. The primary exposure was RC levels. A LASSO Cox model was used to select covariates. The Fine-Gray competing risk model was used to estimate hazard ratios (HRs).

RESULTS

RA patients had a mean age of 53.9 years, and 802 (78.8%) were females. After a median follow-up of 5.54 years, 131 patients developed CVD with an incidence rate of 21.6 per 1000 person-years. Continuous and quartile-categorized RC levels were associated with incident CVD before and after multivariate adjustment and Bonferroni correction (all P < 0.001). There were no robust associations of other lipids with incident CVD. The fully adjusted HRs for RC were 2.30 (95% CI 1.58-3.35) per 1 mmol/L increase, and 2.40 (1.36-4.25) and 2.81 (1.60-4.94) for patients in the 3rd and 4th versus the 1st quartile, respectively.

CONCLUSIONS

Circulating RC levels are positively associated with incident CVD among Chinese RA patients independent of known risk factors, implying its clinically preferable use for improving the stratification of CVD risk in RA patients.

Consequences of low estimated glomerular filtration rate either before or early after kidney donation

In the general population, decreases in glomerular filtration rate (GFR) are associated with subsequent development of chronic kidney disease (CKD), cardiovascular disease (CVD), and death. It is unknown if low estimated GFR (eGFR) before or early after kidney donation was also associated with these risks. One thousand six hundred ninety-nine living donors who had both predonation and early (4-10 weeks) postdonation eGFR were included. We studied the relationships between eGFR, age at donation, and the time to sustained eGFR<45 (CKD stage 3b) and <30 mL/min/1.73m2 (CKD stage 4), hypertension, diabetes mellitus (DM), CVD, and death. Median follow-up was 12 (interquartile range, 6-21) years. Twenty-year event rates were 5.8% eGFR<45 mL/min/1.73m2; 1.2% eGFR<30 mL/min/1.73m2; 29.0% hypertension; 7.8% DM; 8.0% CVD; and 5.2% death. The median time to eGFR<45 mL/min/1.73m2 (N = 79) was 17 years, and eGFR<30 mL/min/1.73m2 (N = 22) was 25 years. Both low predonation and early postdonation eGFR were associated with eGFR<45 mL/min/1.73m2 (P < .0001) and eGFR<30 mL/min/1.73m2 (P < .006); however, the primary driver of risk for all ages was low postdonation (rather than predonation) eGFR. Predonation and postdonation eGFR were not associated with hypertension, DM, CVD, or death. Low predonation and early postdonation eGFR are risk factors for developing eGFR<45 mL/min/1.73m2 (CKD stage 3b) and <30 mL/min/1.73m2 (CKD stage 4), but not CVD, hypertension, DM, or death.

Comprehensive analysis of environmental exposure to hazardous trace elements and lung function: a national cross-sectional study

BACKGROUND

There is growing interest in the joint effects of hazardous trace elements (HTEs) on lung function deficits, but the data are limited. This is a critical research gap given increased global industrialisation.

METHODS

A national cross-sectional study including spirometry was performed among 2112 adults across 11 provinces in China between 2020 and 2021. A total of 27 HTEs were quantified from urine samples. Generalised linear models and quantile-based g-computation were used to explore the individual and joint effects of urinary HTEs on lung function, respectively.

RESULTS

Overall, there were negative associations between forced expiratory volume in 1 s (FEV1) and urinary arsenic (As) (z-score coefficient, -0.150; 95% CI, -0.262 to -0.038 per 1 ln-unit increase), barium (Ba) (-0.148, 95% CI: -0.258 to -0.039), cadmium (Cd) (-0.132, 95% CI: -0.236 to -0.028), thallium (Tl) (-0.137, 95% CI: -0.257 to -0.018), strontium (Sr) (-0.147, 95% CI: -0.273 to -0.022) and lead (Pb) (-0.121, 95% CI: -0.219 to -0.023). Similar results were observed for forced vital capacity (FVC) with urinary As, Ba and Pb and FEV1/FVC with titanium (Ti), As, Sr, Cd, Tl and Pb. We found borderline associations between the ln-quartile of joint HTEs and decreased FEV1 (-20 mL, 95% CI: -48 to +8) and FVC (-14 mL, 95% CI: -49 to+2). Ba and Ti were assigned the largest negative weights for FEV1 and FVC within the model, respectively.

CONCLUSION

Our study investigating a wide range of HTEs in a highly polluted setting suggests that higher urinary HTE concentrations are associated with lower lung function, especially for emerging Ti and Ba, which need to be monitored or regulated to improve lung health.

Evaluation of the clinical value of 10 estimating glomerular filtration rate equations and construction of a prediction model for kidney damage in adults from central China

Objectives

This study aimed to evaluate 10 estimating glomerular filtration rate (eGFR) equations in central China population and construct a diagnostic prediction model for assessing the kidney damage severity.

Methods

The concordance of 10 eGFR equations was investigated in healthy individuals from central China, and their clinical effectiveness in diagnosing kidney injury was evaluated. Subsequently, relevant clinical indicators were selected to develop a clinical prediction model for kidney damage.

Results

The overall concordance between CKD-EPIASR-Scr and CKD-EPI2021-Scr was the highest (weightedκ = 0.964) in healthy population. The CG formula, CKD-EPIASR-Scr and CKD-EPI2021-Scr performed better than others in terms of concordance with referenced GFR (rGFR), but had poor ability to distinguish between rGFR < 90 or < 60 mL/min·1.73 m2. This finding was basically consistent across subgroups. Finally, two logistic regression prediction models were constructed based on rGFR < 90 or 60 mL/min·1.73 m2. The area under the curve of receiver operating characteristic values of two prediction models were 0.811 vs 0.846 in training set and 0.812 vs 0.800 in testing set.

Conclusion

The concordance of CKD-EPIASR-Scr and CKD-EPI2021-Scr was the highest in the central China population. The Cockcroft-Gault formula, CKD-EPIASR-Scr, and CKD-EPI2021-Scr more accurately reflected true kidney function, while performed poorly in the staging diagnosis of CKD. The diagnostic prediction models showed the good clinical application performance in identifying mild or moderate kidney injury. These findings lay a solid foundation for future research on renal function assessment and predictive equations.

Causes of Chronic Kidney Disease and Their Associations with Cardiovascular Risk and Disease in a Sub-Saharan Low-Income Population

Introduction

The causes of chronic kidney disease (CKD) in people living in Sub-Saharan Africa await identification. Also, whether cardiovascular risk and disease extent differ among patients with different CKD etiologies is uncertain.

Methods

In this prospective cross-sectional study, we examined the presumed causes of chronic kidney disease (CKD) and their relationships with cardiovascular risk and disease in 743 consecutive patients from a sub-Saharan low-income population.

Results

Hypertensive nephropathy (HNP) (60.2%), diabetic nephropathy (DNP) (24.4%), HIV associated CKD (20.0%) and glomerular disease (13.6%) comprised the major CKD etiologies upon enrolment at the hospital nephrology clinic. Pulse pressure was larger in patients with concurrent HNP and DNP than in those with HNP only (p<0.001). Pulse pressure and systolic blood pressure were larger in HNP or/and DNP patients than those with HIV associated CKD and glomerular disease (p=0.04 to <0.001). Cardiovascular disease was more prevalent in patients with HNP and concurrent HNP and DNP than those from other etiologic categories (p<0.05). HNP and DNP were associated with pulsatile pressures (pulse pressure and systolic blood pressure) independent of one another (p<0.01). In adjusted product of coefficient mediation analysis, mean arterial or distending pressure accounted fully for the potential impact of HNP on pulsatile pressures (103.9-115.7%) but not for that of DNP on the respective pressures (-2.0%-(-)7.5%).

Conclusion

HNP is by far the most prevalent presumed cause of CKD in this African population. Cardiovascular risk and disease differ markedly across CKD etiological categories.

Effectiveness of patient decision aids in patients with advanced kidney disease: a meta-analysis based on randomized controlled trials

PURPOSE

To systematically evaluate the decision effectiveness of patient decision aids (PtDAs) on the decision-making effect of patients with advanced chronic kidney disease.

METHOD

Two authors independently searched ten electronic databases [Web of science, PubMed, the Cochrane Library, Embase, CINAHL, EBSCO, CBM, CNKI, WanFang DATA and Vip database], to include randomized controlled trials of interventions through PtDAs in patients with advanced chronic kidney disease published from the inception of the database until April 2024. Two authors conducted a comprehensive quality evaluation (Cochrane 5.1.0) before independently extracting and analyzing the data with RevMan 5.2.

RESULTS

The study included 11 randomized controlled trials with a total of 1613 patients. According to the results, PtDAs can improve the decision knowledge [SMD = 0.53, 95% CI (0.26, 0.80), P = 0.0002] and decision preparation [SMD = 2.34, 95% CI (2.04, 2.65), P < 0.00001] of patients with advanced chronic kidney disease. Additionally, there was a substantial decrease in the levels of decision regret [SMD = - 1.33, 95% CI (- 2.11, - 0.55), P < 0.05] and decision conflict [SMD = - 0.88, 95% CI (- 1.47, - 0.28), P = 0.004].

CONCLUSION

The current available evidence indicates that PtDAs can significantly enhance the decision knowledge and decision preparation of patients with advanced chronic kidney disease. Additionally, PtDAs can reduce the levels of decision regret and decision conflict.

TRIAL REGISTRY

CRD42023433798.

The interaction between estimated glomerular filtration rate and dietary magnesium intake and its effect on stroke prevalence: a cross-sectional study spanning 2003-2018

Background

Despite the known associations of dietary magnesium intake and estimated glomerular filtration rate (eGFR) with cardiovascular diseases, their combined effects on stroke risk remain unclear. Therefore, this study aims to explore the associations of dietary magnesium intake and eGFR with stroke risk.

Methods

The National Health and Nutrition Examination Survey (NHANES) data of 37,637 adult participants (≥18 years) from 2003 to 2018 was analyzed. Dietary magnesium intake was categorized as low (≤ 254 mg/day) and normal (> 254 mg/day) based on experimental data. Multiple logistic regression analyses and interaction tests were conducted to assess the associations of dietary magnesium intake and eGFR with stroke risk, with a focus on the interaction between different chronic kidney disease (CKD) stages based on eGFR levels and dietary magnesium intake. Additional analyses included multiplicative interaction analysis, restricted cubic spline analysis, and subgroup evaluations by age, sex, and ethnicity.

Results

Dietary magnesium intake and eGFR were inversely correlated with the risk of stroke. Participants with low dietary magnesium intake had a higher stroke risk than those with normal magnesium intake (odds ratio [OR] 1.09, 95% confidence interval [CI]: 1.03-1.42). Likewise, low eGFR was associated with an elevated stroke risk compared with normal eGFR (OR 1.56, 95% CI: 1.15-2.13). Furthermore, the two factors showed a multiplicative interaction effect on stroke risk (OR 1.05, 95% CI: 1.01-1.09). We observed a significant interaction between stage G3 CKD and low dietary magnesium intake (OR 1.05, 95% CI: 1.01-1.09), suggesting a potential association with stroke risk. However, similar associations were not observed for stages G4 and G5, possibly due to the smaller number of participants with G4 and G5 CKD. The restricted cubic spline analysis revealed a non-linear relationship between dietary magnesium intake, eGFR, and stroke risk. The interaction between magnesium deficiency and low eGFR persisted in participants aged >60 years, as well as in females, non-Hispanic Black people, and people of other races.

Conclusion

Dietary magnesium intake and eGFR correlate negatively with stroke prevalence. Moreover, there was an interaction between dietary magnesium intake and stroke prevalence across different CKD stages. Further large-scale prospective studies are needed to analyze the potential relationship between dietary magnesium intake, eGFR, and stroke.

Prevalence and co-prevalence of comorbidities among Chinese adult patients with type 2 diabetes mellitus: a cross-sectional, multicenter, retrospective, observational study based on 3B study database

Purpose

This study aimed to investigate the prevalence and co-prevalence of comorbidities among Chinese individuals with type 2 diabetes (T2DM).

Methods

Medical records were retrospectively retrieved from the 3B Study database, which provided a comprehensive assessment of comorbid conditions in Chinese adult outpatients with T2DM. Patient characteristics, laboratory measures, and comorbidities were summarized via descriptive analyses, overall and by subgroups of age (<65, 65-74, 75 years) and gender.

Results

Among 25,454 eligible patients, 53% were female, and the median age was 63 years. The median time of diabetes duration was 6.18 years. A total of 20,309 (79.8%) patients had at least one comorbid condition alongside T2DM. The prevalence of patients with one, two, three, and four or more comorbid conditions was 28.0%, 24.6%, 15.6%, and 11.6%, respectively. Comorbidity burden increased with longer T2DM duration. Older age groups also exhibited higher comorbidity burden. Females with T2DM had a higher overall percentage of comorbidities compared to males (42.7% vs. 37.1%). The most common comorbid conditions in T2DM patients were hypertension (HTN) in 59.9%, overweight/obesity in 58.3%, hyperlipidemia in 42.0%, retinopathy in 16.5%, neuropathy in 15.2%, cardiovascular disease (CVD) in 14.9%, and renal disease in 14.4%. The highest co-prevalence was observed for overweight/obesity and HTN (37.6%), followed by HTN and hyperlipidemia (29.8%), overweight/obesity and hyperlipidemia (27.3%), HTN and CVD (12.6%), HTN and retinopathy (12.1%), and HTN and renal disease (11.3%).

Conclusion

The majority of T2DM patients exhibit multiple comorbidities. Considering the presence of multimorbidity is crucial in clinical decision-making.

Systematic review registration

https://clinicaltrials.gov/, identifier NCT01128205.

Associations between bioelectrical impedance analysis-derived phase angle, protein-energy wasting and all-cause mortality in older patients undergoing haemodialysis

AIM

Protein-energy wasting (PEW) is a common syndrome in patients undergoing haemodialysis (HD) and is associated with poor prognosis. Bioelectrical impedance analysis (BIA)-derived phase angle (PA) is useful for predicting PEW, but sex and age need to be considered. We aimed to reveal sex-specific cut-off values of PA predicting PEW in HD patients aged ≥65.

METHODS

This two-centre retrospective cohort study included patients on HD who underwent BIA. PEW was detected using the International Society of Renal Nutrition and Metabolism (ISRNM) criteria as a reference. The PA was measured using a multifrequency bioimpedance device. Sex-specific cut-off values of PA predicting PEW were detected by receiver-operator characteristic analysis. We investigated the association between PEW determined using sex-specific cut-off values for PA and all-cause mortality.

RESULTS

This study included 274 patients undergoing HD, with a median age of 75 (70-80) years, mean PA of 3.8 ± 1.1° and PEW of 43%. Over a median follow-up duration of 1095 (400-1095) days, 111 patients died. Cut-off values of PA predicting PEW were as follows: female, 3.00° (sensitivity, 87.3%; specificity, 77.5%), and male, 3.84° (sensitivity, 77.6%; specificity, 71.4%). The kappa coefficient between sex-specific cut-off values of the PA and ISRNM criteria had a moderate coincidence level of 0.55. PEW detected by PA was independently associated with all-cause mortality (hazard ratio: 2.40; 95% confidence interval: 1.51-3.85; p < .001).

CONCLUSIONS

Sex-specific cut-off values for PA in older HD patients may be useful as a screening tool for predicting PEW and mortality.

Changes in the combination of the triglyceride-glucose index and obesity indicators estimate the risk of cardiovascular disease

BACKGROUND

Cardiovascular disease (CVD) is closely associated with the triglyceride glucose (TyG) index and its related indicators, particularly its combination with obesity indices. However, there is limited research on the relationship between changes in TyG-related indices and CVD, as most studies have focused on baseline TyG-related indices.

METHODS

The data for this prospective cohort study were obtained from the China Health and Retirement Longitudinal Study. The exposures were changes in TyG-related indices and cumulative TyG-related indices from 2012 to 2015. The K-means algorithm was used to classify changes in each TyG-related index into four classes (Class 1 to Class 4). Multivariate logistic regressions were used to evaluate the associations between the changes in TyG-related indices and the incidence of CVD.

RESULTS

In total, 3243 participants were included in this study, of whom 1761 (54.4%) were female, with a mean age of 57.62 years at baseline. Over a 5-year follow-up, 637 (19.6%) participants developed CVD. Fully adjusted logistic regression analyses revealed significant positive associations between changes in TyG-related indices, cumulative TyG-related indices and the incidence of CVD. Among these changes in TyG-related indices, changes in TyG-waist circumference (WC) showed the strongest association with incident CVD. Compared to the participants in Class 1 of changes in TyG-WC, the odds ratio (OR) for participants in Class 2 was 1.41 (95% confidence interval (CI) 1.08-1.84), the OR for participants in Class 3 was 1.54 (95% CI 1.15-2.07), and the OR for participants in Class 4 was 1.94 (95% CI 1.34-2.80). Moreover, cumulative TyG-WC exhibited the strongest association with incident CVD among cumulative TyG-related indices. Compared to the participants in Quartile 1 of cumulative TyG-WC, the OR for participants in Quartile 2 was 1.33 (95% CI 1.00-1.76), the OR for participants in Quartile 3 was 1.46 (95% CI 1.09-1.96), and the OR for participants in Quartile 4 was 1.79 (95% CI 1.30-2.47).

CONCLUSIONS

Changes in TyG-related indices are independently associated with the risk of CVD. Changes in TyG-WC are expected to become more effective indicators for identifying individuals at a heightened risk of CVD.

Association Between Peritoneal Glucose Absorption, Lipid Metabolism, and Cardiovascular Disease Risk in Nondiabetic Patients on Peritoneal Dialysis

BACKGROUND

Excessive sugar intake increases the energy metabolic burden and the risk of cardiovascular disease (CVD). Patients on peritoneal dialysis absorb much more glucose than the World Health Organization recommends, but the link to CVD is unclear.

OBJECTIVE

To identify the association between peritoneal glucose absorption, lipid metabolism, and CVD.

METHODS

We applied generalized additive mixed effects and mixed effects Cox proportional hazard models to evaluate the impact of peritoneal glucose absorption on lipid profiles and CVD risk. We performed subgroup analyses by using protein intake (normalized protein nitrogen appearance [nPNA] and normalized protein catabolic rate [nPCR] were used to assess protein intake) and high-sensitivity C-reactive protein (hs-CRP).

RESULTS

After multivariable adjustment, peritoneal glucose absorption per 10 g/d increase was associated with an increase in cholesterol of 0.145 (95% confidence interval [CI]: 0.086-0.204) mmol/L. No link with the total risk of CVD was observed; however, protein intake and hs-CRP levels affected the relationship between glucose absorption and CVD risk. Patients with values for nPNA and nPCR <1.0 g/(kg·d) were associated with a lower risk of CVD (hazard ratio [HR] 95% CI: 0.68 (0.46-0.98)) with glucose absorption per 10 g/d increase. While patients with hs-CRP levels ≥3 mg/d or values for nPNA or nPCR ≥1.0 g/(kg·d) were associated with a higher risk of CVD (HR 95% CI: 1.32 (1.07-1.63); 1.31 (1.02-1.68)) for glucose absorption per 10 g/d increase.

CONCLUSIONS

Our study found a positive correlation between peritoneal glucose absorption and lipid profiles. Increased glucose absorption was associated with a lower risk of CVD in lower protein intake patients and a higher risk of CVD in higher hs-CRP or protein intake levels in patients on peritoneal dialysis.

Mechanism of protective actions of sparsentan in the kidney: lessons from studies in models of chronic kidney disease

Simultaneous inhibition of angiotensin II AT1 and endothelin ETA receptors has emerged as a promising approach for treatment of chronic progressive kidney disease. This therapeutic approach has been advanced by the introduction of sparsentan, the first dual AT1 and ETA receptor antagonist. Sparsentan is a single molecule with high affinity for both receptors. It is US Food and Drug Administration approved for immunoglobulin A nephropathy (IgAN) and is currently being developed as a treatment for rare kidney diseases, such as focal segmental glomerulosclerosis. Clinical studies have demonstrated the efficacy and safety of sparsentan in these conditions. In parallel with clinical development, studies have been conducted to elucidate the mechanisms of action of sparsentan and its position in the context of published evidence characterizing the nephroprotective effects of dual ETA and AT1 receptor inhibition. This review summarizes this evidence, documenting beneficial anti-inflammatory, antifibrotic, and hemodynamic actions of sparsentan in the kidney and protective actions in glomerular endothelial cells, mesangial cells, the tubulointerstitium, and podocytes, thus providing the rationale for the use of sparsentan as therapy for focal segmental glomerulosclerosis and IgAN and suggesting potential benefits in other renal diseases, such as Alport syndrome.

Targeting the endothelium by combining endothelin-1 antagonism and SGLT-2 inhibition: better together?

Endothelin A and B receptors, together with sodium-glucose cotransporter-2 (SGLT-2) channels are important targets in improving endothelial function and intervention with inhibitors has been the subject of multiple mechanistic and clinical outcome trials over recent years. Notable successes include the treatment of pulmonary hypertension with endothelin receptor antagonists, and the treatment of heart failure and chronic kidney disease with SGLT-2 inhibitors. With distinct and complementary mechanisms, in this review, we explore the logic of combination therapy for a number of diseases which have endothelial dysfunction at their heart.

Renal fat deposition measured on dixon-based MRI is significantly associated with early kidney damage in obesity

PURPOSE

To investigate the renal fat deposition on Dixon-based magnetic resonance imaging (MRI) and to explore the predictive value of renal fat biomarkers of magnetic resonance (MR-RFBs) for early kidney damage in obesity.

METHODS

This prospective study included 56 obese volunteers and 47 non-obese healthy volunteers. All volunteers underwent renal magnetic resonance examinations. The differences in MR-RFBs [including renal proton density fat fraction (PDFF), renal sinus fat volume (RSFV), and perirenal fat thickness (PRFT)] measured on Dixon-based MRI between the obese and non-obese volunteers were analyzed using a general linear model, taking sex, age, diabetes, and hypertension as covariates. The relationship between estimated glomerular filtration rate (eGFR) and demographic, laboratory, and imaging parameters in obese volunteers was examined by correlation analysis.

RESULTS

Obese volunteers had higher MR-RFBs than non-obese volunteers after controlling for confounders (all p < 0.001). Renal PDFF (r = - 0.383; p = 0.004), RSFV (r = - 0.368; p = 0.005), and PRFT (r = - 0.451; p < 0.001) were significantly negatively correlated with eGFR in obesity. After adjusting for age, sex, body mass index, diabetes, hypertension, visceral adipose tissue, subcutaneous adipose tissue, renal PDFF, and RSFV, PRFT remained independently negatively associated with eGFR (β = - 0.587; p = 0.003).

CONCLUSIONS

All MR-RFBs are negatively correlated with eGFR in obesity. The MR-RFBs, especially PRFT, may have predictive value for early kidney damage in obesity.

Is endothelin targeting finally ready for prime time?

The endothelin family of peptides has long been recognized as a physiological regulator of diverse biological functions and mechanistically involved in various disease states, encompassing, among others, the cardiovascular system, the kidney, and the nervous system. Pharmacological blockade of the endothelin system, however, has encountered strong obstacles in its entry into the clinical mainstream, having obtained only a few proven indications until recently. This translational gap has been attributable predominantly to the relevant side effects associated with endothelin receptor antagonism (ERA), particularly fluid retention. Of recent, however, an expanding understanding of the pathophysiological processes involving endothelin, in conjunction with the development of new antagonists of endothelin receptors or adjustment of their doses, has driven a flourish of new clinical trials. The favorable results of some of them have extended the proven indications for ET targeting to a variety of clinical conditions, including resistant arterial hypertension and glomerulopathies. In addition, on the ground of strong preclinical evidence, other studies are ongoing to test the potential benefits of ERA in combination with other treatments, such as sodium-glucose co-transporter 2 inhibition in fluid retentive states or anti-cancer therapies in solid tumors. Furthermore, antibodies providing long-term blockade of endothelin receptors are under testing to overcome the short half-life of most small molecule endothelin antagonists. These efforts may yet bring new life to the translation of endothelin targeting strategies in clinical practice.

Magnoflorine Ameliorates Chronic Kidney Disease in High-Fat and High-Fructose-Fed Mice by Promoting Parkin/PINK1-Dependent Mitophagy to Inhibit NLRP3/Caspase-1-Mediated Pyroptosis

Excessive intake of fat and fructose in Western diets has been confirmed to induce renal lipotoxicity, thereby driving the progression of chronic kidney disease (CKD). This study was conducted to evaluate the efficacy of magnoflorine in a CKD mouse model subjected to high-fat and high-fructose diets. Our results demonstrated that magnoflorine treatment ameliorated abnormal renal function indices (serum creatinine, urea nitrogen, uric acid, and urine protein) in high-fat- and high-fructose-fed mice. Histologically, renal tubular cell steatosis, lipid deposition, tubular dilatation, and glomerular fibrosis were significantly reduced by the magnoflorine treatment in these mice. Mechanistically, magnoflorine promotes Parkin/PINK1-mediated mitophagy, thereby inhibiting NLRP3/Caspase-1-mediated pyroptosis. Consistent findings were observed in the palmitic acid-incubated HK-2 cell model. Notably, both silencing of Parkin and the use of a mitophagy inhibitor reversed the inhibitory effect of magnoflorine on NLRP3 inflammasome activation in vitro. Therefore, the present study provides compelling evidence that magnoflorine improves renal injury in high-fat- and high-fructose-fed mice by promoting Parkin/PINK1-dependent mitophagy to inhibit NLRP3 inflammasome activation and pyroptosis. Our findings suggest that dietary supplementation with magnoflorine and magnoflorine-rich foods (such as magnolia) might be an effective strategy for the prevention of CKD.

Metformin for preventing the progression of chronic kidney disease

BACKGROUND

Metformin has been used in the management of diabetes for decades. It is an effective, low-cost intervention with a well-established safety profile. Emerging evidence suggests that metformin targets a number of pathways that lead to chronic kidney damage, and long-term use may, therefore, slow the rate of kidney function decline and chronic kidney disease (CKD) progression.

OBJECTIVES

To evaluate the effect of metformin therapy on kidney function decline in patients with CKD with or without diabetes mellitus and assess the safety and dose tolerability in this population.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 19 July 2023 with assistance from an Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that reported kidney-related outcomes with a minimum duration of 12 months delivery of the metformin intervention and whose eligibility criteria included adult participants with either i) a diagnosis of CKD of any aetiology and/or ii) those with a diagnosis of diabetes mellitus. Comparisons included placebo, no intervention, non-pharmacological interventions, other antidiabetic medications or any other active control. Studies that included patients on any modality of kidney replacement therapy were excluded.

DATA COLLECTION AND ANALYSIS

Two authors independently carried out data extraction using a standard data extraction form. The methodological quality of the included studies was assessed using the Cochrane risk of bias tool. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes and mean difference (MD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

This review included 11 studies reporting on 8449 randomised participants. Studies were conducted in patient populations with Autosomal Dominant Polycystic Kidney Disease (ADPKD) (four studies) or diabetes mellitus (seven studies). Six studies compared metformin with no active control, four studies compared metformin with active controls (rosiglitazone, glyburide, pioglitazone, or glipizide), and one study included treatment arms that randomised to either metformin, diet and lifestyle modifications, or other antidiabetic therapies. The risk of bias in included studies varied; two studies were abstract-only publications and were judged to have a high risk of bias in most domains. Other included publications were judged to have a low risk of bias in most domains. Across comparisons, GRADE evaluations for most outcomes were judged as low or very low certainty, except for those relating to side effects, tolerance, and withdrawals, which were judged as moderate certainty. The evidence suggests that compared to placebo, metformin may result in i) a slightly smaller decline in kidney function (3 studies, 505 participants: MD 1.92 mL/min, 95% CI 0.33 to 3.51; I2 = 0%; low certainty), ii) very uncertain effects on the incidence of kidney failure (1 study, 753 participants: RR 1.20, 95% CI 0.17 to 8.49), iii) little or no effect on death (3 studies, 865 participants: RR 1.00, 95% CI 0.76 to 1.32; I2 = 0%; moderate certainty), iv) little or no effect on the incidence of serious adverse events (3 studies, 576 participants: RR 1.15, 95% CI 0.76 to 1.72; I2 = 0%; moderate certainty), and v) likely higher incidence of intolerance leading to study withdrawal than placebo (4 studies, 646 participants: RR 2.19, 95% CI 1.46 to 3.27; I2 = 0%; moderate certainty). The certainty of the evidence for proteinuria was very uncertain. Compared to other active controls (rosiglitazone, glyburide, pioglitazone, or glipizide), metformin i) demonstrated very uncertain effects on kidney function decline, ii) may result in little or no difference in death (3 studies, 5608 participants: RR 0.95 95% CI 0.63 to 1.43; I2 = 0%; low certainty), iii) probably results in little or no difference in intolerance leading to study withdrawal (3 studies, 5593 participants: RR 0.92, 95% CI, 0.79 to 1.08; I2 = 0%; moderate certainty), iv) probably results in little or no difference in the incidence of serious adverse events (2 studies, 5545 participants: RR 1.16, 95% CI 0.79 to 1.71; I2 = 0%; moderate certainty), and v) may increase the urinary albumin-creatinine ratio (2 studies, 3836 participants: MD 14.61, 95% CI 8.17 to 21.05; I2 = 0%; low certainty). No studies reported the incidence of kidney failure.

AUTHORS' CONCLUSIONS

This review highlights the lack of RCTs reporting on the effects of metformin on kidney function, particularly in patients with CKD. Future research in this field requires adequately powered RCTs comparing metformin to placebo or standard care in those with CKD. Seven ongoing studies were identified in this review, and future updates, including their findings, may further inform the results of this review.

Does Metabolic Syndrome and Its Components Have Prognostic Significance for Renal and Cardiovascular Outcomes in IgA Nephropathy?

BACKGROUND

Patients with IgA nephropathy (IgAN), a chronic kidney disease (CKD), are significantly more likely to have cardiovascular (CV) mortality and morbidity than the general population. The occurrence of metabolic syndrome (MetS) and metabolic risk factors are independent risk factors for CV disease and renal progression. The purpose of this study was to determine how metabolic characteristics in a homogeneous population of CKD patients relate to prognosis.

METHODS

A total of 145 patients with CKD stages 1-4 diagnosed with IgA nephropathy (92 men and 53 women, aged 54.7 ± 13 years) were examined and monitored for a median of 190 months. All-cause mortality and any CV event, such as stroke, myocardial infarction, revascularization (CV), end-stage renal disease, and renal replacement therapy (renal), have been included in the composite endpoints (CV and renal).

RESULTS

Patients with MetS had significantly more primary endpoint events (23/65 patients vs. 15/60 patients, p < 0.001) compared to the non-MetS group. The MetS group had a statistically significant increase in both primary renal and CV endpoints (18/65 vs. 10/60, p = 0.001), and in CV endpoint events (7/65 vs. 6/60, p = 0.029) among the secondary endpoints (CV and renal separately). Based on Cox regression analysis, the main endpoint independent predictors of survival were dyslipidemia, eGFR, hemoglobin, urine albuminuria, and diabetes mellitus. Independent predictors of secondary renal endpoints were dyslipidemia, hemoglobin, urine albumin, and eGFR. Predictors of secondary cardiovascular endpoints were gender, BMI, and diabetes. When Kaplan-Meier curves were analyzed at the combined endpoints (CV and renal) or each endpoint independently, significant differences were seen between MetS and non-MetS. With more MetS components, the primary endpoint rate increased significantly (MetS comp. 0 vs. MetS comp. 2+, primary endpoints, p = 0.012).

CONCLUSIONS

Our results show that the metabolic profile has a prognostic role not only for renal endpoints but also for CV endpoints in IgAN. BMI, hyperuricemia, hypertension, and diabetes have a predictive value for the prognosis of IgA nephropathy.

Loneliness, social isolation and incident chronic kidney disease among patients with diabetes

Background

Individuals with diabetes have a significantly higher risk of developing chronic kidney disease (CKD) and higher levels of social isolation and loneliness compared with those without diabetes. Recently, the American Heart Association highlighted the importance of considering social determinants of health (SDOH) in conjunction with traditional risk factors in patients with diabetes.

Aims

To investigate the associations of loneliness and social isolation with incident CKD risk in patients with diabetes in the UK Biobank.

Methods

A total of 18 972 patients with diabetes were included in this prospective study. Loneliness and Social Isolation Scales were created based on self-reported factors. An adjusted Cox proportional hazard model was used to investigate the associations of loneliness and social isolation with CKD risk among patients with diabetes. The relative importance in predicting CKD was also calculated alongside traditional risk factors.

Results

During a median follow-up of 10.8 years, 1127 incident CKD cases were reported. A higher loneliness scale, but not social isolation, was significantly associated with a 25% higher risk of CKD, independent of traditional risk factors, among patients with diabetes. Among the individual loneliness factors, the sense of feeling lonely emerged as the primary contributing factor to the elevated risk of CKD. Compared with individuals not experiencing feelings of loneliness, those who felt lonely exhibited a 22% increased likelihood of developing CKD. In addition, feeling lonely demonstrated greater relative importance of predicting CKD compared with traditional risk factors such as body mass index, smoking, physical activity and diet.

Conclusions

This study indicates the significant relationship between loneliness and CKD risk among patients with diabetes, highlighting the need to address SDOH in preventing CKD in this population.

Occupational particle exposure and chronic kidney disease: a cohort study in Swedish construction workers

OBJECTIVES

Increasing epidemiological and experimental evidence suggests that particle exposure is an environmental risk factor for chronic kidney disease (CKD). However, only a few case-control studies have investigated this association in an occupational setting. Hence, our objective was to investigate associations between particle exposure and CKD in a large cohort of Swedish construction workers.

METHODS

We performed a retrospective cohort study in the Swedish Construction Workers' Cohort, recruited 1971-1993 (n=286 089). A job-exposure matrix was used to identify workers exposed to nine different particulate exposures, which were combined into three main categories (inorganic dust and fumes, wood dust and fibres). Incident CKD and start of renal replacement therapy (RRT) were obtained from validated national registries until 2021 and analysed using adjusted Cox proportional hazards models.

RESULTS

Exposure to inorganic dust and fumes was associated with an increased risk of CKD and RRT during working age (adjusted HR for CKD at age <65 years 1.15, 95% CI 1.05 to 1.26). The elevated risk did not persist after retirement age. Exposure to cement dust, concrete dust and diesel exhaust was associated with CKD. Elevated HRs were also found for quartz dust and welding fumes.

CONCLUSIONS

Workers exposed to inorganic particles seem to be at elevated risk of CKD and RRT. Our results are in line with previous evidence of renal effects of ambient air pollution and warrant further efforts to reduce occupational and ambient particle exposure.

Remnant cholesterol and intensive blood pressure control in older patients with hypertension: a post hoc analysis of the STEP randomized trial†

AIMS

Emerging evidence shows a close relationship between remnant cholesterol (RC) and hypertension. However, it is unknown whether RC is associated with the effects of intensive systolic blood pressure (SBP) lowering on cardiovascular outcomes.

METHODS AND RESULTS

We performed a post hoc analysis of the Strategy of Blood Pressure Intervention in the Elderly Hypertensive Patients (STEP) trial. Participants were randomly allocated to intensive (110 to <130 mmHg) or standard (130 to <150 mmHg) treatment groups. The effects of intensive SBP lowering on the primary composite outcome (stroke, acute coronary syndrome, acute decompensated heart failure, coronary revascularization, atrial fibrillation, or cardiovascular death), the components thereof, and all-cause mortality were analysed by the tertile of baseline RC (lowest, middle, and highest). We followed 8206 patients for 3.33 years (median). The adjusted hazard ratios (HRs) [95% confidence interval (CI)] for the primary outcome were 1.06 (0.73-1.56), 0.58 (0.38-0.87), and 0.67 (0.46-0.96) in the lowest, middle, and highest RC tertiles, respectively (P for interaction = 0.11). However, significant heterogeneity in the treatment effects was observed when comparing the upper two tertiles with the lowest tertile (P for interaction = 0.033). For all-cause mortality, the adjusted HRs (95% CI) were 2.48 (1.30-4.73), 1.37 (0.71-2.65), and 0.42 (0.22-0.80) in the lowest, middle, and highest RC tertiles, respectively (P for interaction <0.0001).

CONCLUSION

Baseline RC concentrations were associated with the effects of intensive SBP lowering on the primary composite cardiovascular outcome and all-cause mortality in hypertensive patients. These results are hypothesis-generating and merit further study.

REGISTRATION

STEP ClinicalTrials.gov number: NCT03015311.