Paradoxical association between body mass index and mortality in men with CKD not yet on dialysis

Obesity and Metabolic Health in CKD

Obesity is a worldwide epidemic with a future projected growth of 40% over 10 years. Obesity increases the risk of diabetes, hypertension, and cardiovascular disease, and it also leads to higher risk of CKD, through both direct and indirect mechanisms. Although obesity is a feature of overnutrition and is associated with poor outcomes in the general population, obese individuals with CKD often display complex metabolic patterns such as sarcopenic obesity, and obesity can be associated with better survival in individuals with advanced CKD. Weight loss interventions are proven to improve glycemic control and cardiovascular risk factors, and successful weight loss is associated with improved albuminuria in patients with preexisting CKD. The long-term effects of weight loss interventions on kidney function and on survival in patients with CKD are less well studied, and hence, such interventions should be individualized.

Sarcopenic obesity in predialysis chronic kidney disease: Muscle strength is a predictor of mortlity and disease progression in a six-year prospective cohort

INTRODUCTION

Sarcopenic obesity (SO) is a poorly defined physiological condition that is associated with increased morbimortality in the general population. The prevalence of SO has increased, making it an important public health issue; however, its effects when associated with other chronic conditions are still unclear. Therefore, it is necessary to comprehend the potential outcomes in chronic kidney disease (CKD) patients.

OBJECTIVE

To assess the associations of predialysis CKD patients with SO and its components with death and disease progression to renal replacement therapy (RRT).

METHODS

Prospective six-year cohort with 100 patients with predialysis CKD (stages one through five). Participants were older than 18 years and signed an informed consent form. The data were collected in an outpatient clinic specializing in predialysis care, and demographic, clinical, laboratory and inflammatory variable data were collected. A descriptive analysis was performed, and the SO and non-SO groups were compared with Student's t test, Mann‒Whitney U test and Cox regression, taking into consideration all relevant confounding variables. Body composition variables utilized to diagnose SO were separately analyzed along with the outcomes.

RESULTS

Sixteen percent of our sample were diagnosed with SO, but this was not associated with death or RRT, while lower BMI values were negatively associated with these outcomes. However, in an isolated analysis, handgrip strength was correlated with both RRT (p = 0.029) and death (p = 0.003). We recommend that health professionals pay greater attention to muscle strength, striving for earlier assessment, in an effort to better counsel patients and implement actions to increase or preserve strength through nonpharmacological treatment, such as resistance training.

Personalized Nutrition in Chronic Kidney Disease

A personalized approach to nutrition in patients with chronic kidney disease (CKD) represents a promising paradigm shift in disease management, moving beyond traditional one-size-fits-all dietary recommendations. Patients with CKD often have other comorbidities and face unique nutritional challenges, including protein-energy wasting (PEW), sarcopenia, and impaired renal excretion of nutrients, which complicate dietary planning. Current guidelines focus primarily on nutrient restrictions-such as limiting protein, sodium, potassium, and phosphorus. However, these generalized recommendations often result in suboptimal adherence and outcomes. Personalized nutrition, which adapts dietary recommendations to individual characteristics, such as genotype, phenotype, and socio-cultural preferences, has gained traction across various chronic diseases. However, its application in nephrology remains underexplored, and despite promising results from studies such as Food4Me, questions remain about the real-world impact of such strategies. The aims of this review are (1) to summarize the evidence on the current state of nutritional recommendations in CKD, (2) to discuss the emerging role of multi-omics approaches in informing personalized nutrition advice in CKD, and (3) to provide an opinion on nutritional challenges faced by patients with CKD and the importance of collaboration with the renal dietician. We conclude that despite barriers, such as the cost and data integration, personalized nutrition holds the potential to improve CKD outcomes, enhance quality of life, and empower patients through tailored dietary strategies for better disease management.

Association of systemic immune-inflammation index with all-cause and cardio-cerebrovascular mortality in individuals with diabetic kidney disease: evidence from NHANES 1999-2018

Background

Emerging evidence suggests a potential role of immune response and inflammation in the pathogenesis of diabetic kidney disease (DKD). The systemic immune-inflammation index (SII) offers a comprehensive measure of inflammation; however, its relationship with the prognosis of DKD patients remains unclear.

Methods

Using data from the National Health and Nutrition Examination Survey (NHANES) spanning 1999 to 2018, this cross-sectional study involved adults diagnosed with DKD. Cox proportional hazards models were utilized to assess the associations between SII and all-cause or cardio-cerebrovascular disease mortality. Additionally, restricted cubic spline, piecewise linear regression, and subgroup analyses were performed.

Results

Over a median follow-up duration of 6.16 years, 1338 all-cause deaths were recorded. After adjusting for covariates, elevated SII levels were significantly associated with increased risks of all-cause and cardio-cerebrovascular disease mortality. Specifically, per one-unit increment in natural log-transformed SII (lnSII), there was a 29% increased risk of all-cause mortality (P < 0.001) and a 23% increased risk of cardio-cerebrovascular disease mortality (P = 0.01) in the fully adjusted model. Similar results were observed when SII was analyzed as a categorical variable (quartiles). Moreover, nonlinear association was identified between SII and all-cause mortality (P < 0.001) through restricted cubic spline analysis, with threshold value of 5.82 for lnSII. The robustness of these findings was confirmed in subgroup analyses. Likewise, the statistically significant correlation between SII levels and cardio-cerebrovascular disease mortality persisted in individuals with DKD.

Conclusion

Increased SII levels, whether examined as continuous variables or categorized, demonstrate a significant association with elevated risks of all-cause and cardio-cerebrovascular disease mortality among DKD patients. These findings imply that maintaining SII within an optimal range could be crucial in reducing mortality risk.

Relationships of Weight Change from 20 Years of Age with the Risks of All-Cause and Cardiovascular Mortality in Patients with Chronic Kidney Disease

AIMS

Weight changes from a young age are known to be associated with poor life outcomes in the general population. However, little is known about the association between weight change from a young age and life expectancy in patients with chronic kidney disease (CKD).

METHODS

Data of 2,806 nondialysis CKD patients who participated in the Fukuoka Kidney Disease Registry (FKR) Study, a multicenter observational study, were analyzed. The primary outcome was all-cause death, whereas the secondary outcome was cardiovascular mortality. The covariate of interest was weight change, defined as the difference between body weight at study enrollment and at 20 years old. Cox proportional-hazards models were used to estimate the risks of mortality for participants with weight changes of ≥ 5 or ＜5 kg compared with those with stable weights.

RESULTS

During the 5-year observation period, 243 participants died from all causes and 62 from cardiovascular disease. The risk of all-cause mortality in the weight-loss group was significantly higher than that in the stable-weight group (multivariable-adjusted hazard ratio, 2.11; 95% confidence interval [CI], 1.52-2.93). Conversely, the risk of cardiovascular mortality in the weight-loss group was significantly higher than that in the stable-weight group (multivariable-adjusted hazard ratio, 2.48; 95% CI, 1.32-4.64). However, no significant association was observed between weight gain and the risks of all-cause and cardiovascular mortalities.

CONCLUSION

Weight loss from 20 years of age was found to be associated with higher risks of all-cause and cardiovascular mortalities in patients with CKD.

Associations of exposure to organochlorine pesticides and polychlorinated biphenyls with chronic kidney disease among adults: the modifying effects of lifestyle

Exposure to organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) has been reported to be associated with renal impairment and chronic kidney disease (CKD). Nevertheless, the research results thus far have exhibited inconsistency, and the effect of lifestyle on their association is not clear. In this study, we assessed the correlation between serum OCPs/PCBs and CKD and renal function indicators including estimated glomerular filtration rate (eGFR) and albumin-to-creatinine ratio (ACR) among 1721 Chinese adults. In order to further investigate the potential impact of lifestyle, we conducted joint associations of lifestyle and OCPs/PCBs on CKD. We found a negative correlation between p,p'-DDE and eGFR, while logistic regression results showed a positive correlation between PCB-153 and CKD (OR, 1.92; 95% CI, 1.21, 3.06). Quantile g-computation regression analyses showed that the association between co-exposure to OCPs/PCBs and CKD was not significant, but p,p'-DDE and PCB-153 were the main contributors to the negative and positive co-exposure effects of eGFR and CKD, respectively, which is consistent with the regression results. Participants with both relatively high PCB-153 exposure and an unhealthy lifestyle had the highest risk of CKD, in the joint association analysis. The observed associations were generally supported by the FAS-eGFR method. Our research findings suggest that exposure to OCPs/PCBs may be associated with decreased eGFR and increased prevalence of CKD in humans, and a healthy lifestyle can to some extent alleviate the adverse association between PCB-153 exposure and CKD.

Lipid parameters, adipose tissue distribution and prognosis prediction in chronic kidney Disease patients

BACKGROUND

Lipid management in clinic is critical to the prevention and treatment of Chronic kidney disease (CKD), while the manifestations of lipid indicators vary in types and have flexible association with CKD prognosis.

PURPOSE

Explore the associations between the widely used indicators of lipid metabolism and their distribution in clinic and CKD prognosis; provide a reference for lipid management and inform treatment decisions for patients with non-dialysis CKD stage 3-5.

METHODS

This is a retrospective cohort study utilizing the Self-Management Program for Patients with Chronic Kidney Disease Cohort (SMP-CKD) database of 794 individuals with CKD stages 3-5. It covers demographic data, clinical diagnosis and medical history collection, laboratory results, circulating lipid profiles and lipid distribution assessments. Primary endpoint was defined as a composite outcome(the initiation of chronic dialysis or renal transplantation, sustained decline of 40% or more in estimated glomerular filtration rate (eGFR), doubled of serum creatinine (SCr) from the baseline, eGFR less than 5 mL/min/1.73m2, or all-cause mortality). Exposure variables were circulating lipid profiles and lipid distribution measurements. Association were assessed using Relative risks (RRs) (95% confidence intervals (CIs)) computed by multivariate Poisson models combined with least absolute shrinkage and selection operator (LASSO) regression according to categories of lipid manifestations. The best model was selected via akaike information criterion (AIC), area under curve (AUC), receiver operating characteristic curve (ROC) and net reclassification index (NRI). Subgroup analysis and sensitivity analysis were performed to assess the interaction effects and robustness..

RESULTS

255 individuals reached the composite outcome. Median follow-up duration was 2.03 [1.06, 3.19] years. Median age was 58.8 [48.7, 67.2] years with a median eGFR of 33.7 [17.6, 47.8] ml/min/1.73 m2. Five dataset were built after multiple imputation and five category-based Possion models were constructed for each dataset. Model 5 across five datasets had the best fitness with smallest AIC and largest AUC. The pooled results of Model 5 showed that total cholesterol (TC) (RR (95%CI) (per mmol/L) :1.143[1.023,1.278], P = 0.018) and percentage of body fat (PBF) (RR (95%CI) (per percentage):0.976[0.961,0.992], P = 0.003) were significant factors of composite outcome. The results indicated that comprehensive consideration of lipid metabolism and fat distribution is more critical in the prediction of CKD prognosis..

CONCLUSION

Comprehensive consideration of lipid manifestations is optimal in predicting the prognosis of individuals with non-dialysis CKD stages 3-5.

Strategy of targeting the tumor microenvironment via inhibition of fibroblast/fibrosis remodeling new era to cancer chemo-immunotherapy resistance

The use of repurposing drugs that may have neoplastic and anticancer effects increases the efficiency and decrease resistance to chemotherapy drugs through a biochemical and mechanical transduction mechanisms through modulation of fibroblast/fibrosis remodeling in tumor microenvironment (TME). Interestingly, fibroblast/fibrosis remodeling plays a vital role in mediating cancer metastasis and drug resistance after immune chemotherapy. The most essential hypothesis for induction of chemo-immunotherapy resistance is via activation of fibroblast/fibrosis remodeling and preventing the infiltration of T cells after is mainly due to the interference between cytoskeleton, mechanical, biochemical, metabolic, vascular, and remodeling signaling pathways in TME. The structural components of the tumor that can be targeted in the fibroblast/fibrosis remodeling include the depletion of the TME components, targeting the cancer-associated fibroblasts and tumor associated macrophages, alleviating the mechanical stress within the ECM, and normalizing the blood vessels. It has also been found that during immune-chemotherapy, TME injury and fibroblast/fibrosis remodeling causes the up-regulation of inhibitory signals and down-regulation of activated signals, which results in immune escape or chemo-resistance of the tumor. In this regard, repurposing or neo-adjuvant drugs with various transduction signaling mechanisms, including anti-fibrotic effects, are used to target the TME and fibroblast/fibrosis signaling pathway such as angiotensin 2, transforming growth factor-beta, physical barriers of the TME, cytokines and metabolic factors which finally led to the reverse of the chemo-resistance. Consistent to many repurposing drugs such as pirfenidone, metformin, losartan, tranilast, dexamethasone and pentoxifylline are used to decrease immune-suppression by abrogation of TME inhibitory signal that stimulates the immune system and increases efficiency and reduces resistance to chemotherapy drugs. To overcome immunosuppression based on fibroblast/fibrosis remodeling, in this review, we focus on inhibitory signal transduction, which is the physical barrier, alleviates mechanical stress and prevents mechano-metabolic activation.

Mapping the global research landscape on malnutrition for patients with chronic kidney disease: a visualization analysis

BACKGROUND

Chronic kidney disease (CKD) is seen as a diverse disease and a primary contributor to global mortality. Malnutrition arises within chronic illness, which involves protein energy depletion and inadequate levels of essential nutrients. These factors increase the likelihood of death and the overall impact of the disease on affected individuals. Consequently, this study aims to utilize bibliometric and visual analysis to assess the current state of research, the latest advances and emerging patterns in the fields of CKD and malnutrition.

METHODS

Extensive research was conducted using the Scopus database, which is the most authoritative database of research publications and citations, to focus on CKD research between 2003 and 2022, as indicated by title and author keywords. Then, within this vast collection of academic publications, a notable subset of articles was exclusively dedicated to investigating the relationship between CKD and malnutrition. Finally, we performed bibliometric analysis and visualization using VOSviewer 1.6.19 and Microsoft Excel 2013.

RESULTS

Large global research between 2003 and 2022 resulted in 50,588 documents focused on CKD, as indicated by title and author keywords. In this extensive collection of scientific publications, a staggering portion of 823 articles is devoted exclusively to investigating the link between CKD and malnutrition. Further analysis reveals that this body of work consists of 565 articles (68.65%), 221 reviews (26.85%), and 37 miscellaneous entries (4.50%), which encompass letters and editorials. The USA was found to be the most productive country (n = 173; 21.02%), followed by Italy (n = 83; 10.09%), Sweden (n = 56; 6.80%), Brazil (n = 54; 6.56%) and China (n = 51; 6.20%). The most common terms on the map include those related to the topic of (a) malnutrition in hemodialysis patients and predicting factors; terms associated with the (b) impact of malnutrition on cardiovascular risk and complications in CKD patients; and terms related to the (c) dietary protein intake and malnutrition in CKD.

CONCLUSIONS

This study is the first of its kind to analyze CKD and malnutrition research using data from Scopus for visualization and network mapping. Recent trends indicate an increasing focus on protein-energy wasting/malnutrition in hemodialysis patients and predicting factors, dietary protein intake, and malnutrition in CKD. These topics have gained significant attention and reflect the latest scientific advances. Intervention studies are crucial to examining diet therapy's impact on patients with stages 1 to 5 CKD. We hope this study will offer researchers, dietitians and nephrologists valuable information.

Divergent functions of NLRP3 inflammasomes in cancer: a review

The cancer is a serious health problem, which is The cancer death rate (cancer mortality) is 158.3 per 100,000 men and women per year (based on 2013-2017 deaths). Both clinical and translational studies have demonstrated that chronic inflammation is associated with Cancer progression. However, the precise mechanisms of inflammasome, and the pathways that mediate this phenomenon are not fully characterized. One of the most recently identified signaling pathways, whose activation seems to affect many metabolic disorders, is the "inflammasome" a multiprotein complex composed of NLRP3 (nucleotide-binding domain and leucine-rich repeat protein 3), ASC (apoptosis associated speck-like protein containing a CARD), and procaspase-1. NLRP3 inflammasome activation leads to the processing and secretion of the proinflammatory cytokines interleukin-1β (IL-1β) and IL-18. The goal of this paper is to review new insights on the effects of the NLRP3 inflammasome activation in the complex mechanisms of crosstalk between different organs, for a better understanding of the role of chronic inflammation in cancer pathogenesis. We will provide here a perspective on the current research on NLRP3 inflammasome, which may represent an innovative therapeutic target to reverse the malignancy condition consequences of the inflammation. Video Abstract.

Anthropometric Measures of Adiposity as Markers of Kidney Dysfunction: A Cross-Sectional Study

The present study was designed to provide information on the ability of several different anthropometric markers to reflect the renal impairment associated with body weight increase and to predict the development of renal alterations linked to overweight and obesity. In 574 subjects representative of the general population of the Pressioni Arteriose Monitorate e Loro Associazioni (PAMELA) study, with an age range between 57 and 73 years, we investigated the association between different anthropometric markers of body fat, as alternative to body mass index, and renal failure, to obtain information useful for determining their potential predictive value. Renal dysfunction was significantly associated with almost all anthropometric markers of adiposity related to body weight and body shape. After adjustment for confounders, such as age, sex, office blood pressure, serum glucose, antihypertensive drugs and smoking habit, association remained significant only for waist-to-hip ratio (WHR), lipid accumulation product (LAP) and visceral adiposity index (VAI). These 3 markers also displayed at the receiver operating curves (ROC) analysis the best ability to detect subjects with or without kidney dysfunction. The results of the present study provide evidence that WHR, LAP and VAI represent the best markers of renal dysfunction associated with visceral body fat accumulation.

Elevated Crude Mortality in Obese Chronic Kidney Disease Patients with Loss of Exercise Habit: A Cohort Study of the Japanese General Population

Objective The relationship between obesity and risk of death in chronic kidney disease (CKD) patients remains controversial. In addition, no clear evidence has been accumulated regarding whether or not exercise improves mortality in CKD patients. Methods The original cohort was based on a Japanese general population of 685,889 people from 40 to 74 years old who had undergone annual specific health checkups. The number of all-cause deaths during follow-up (mean, 4.7 years) in this study was 1,490. Information on walking and exercise habits was obtained by questionnaires. The study population was divided into 4 categories by the combination of CKD and obesity [body mass index (BMI) ≥25.0 kg/m2]. Changes in the BMI and walking and exercise habits were determined by results for the first year and following year. Results Obese CKD patients with weight gain (BMI increase by more than +1.0 kg/m2/year) showed a higher crude mortality (1.32%) than those with a stable BMI (within ±1.0 kg/m2/year; 0.69%). In the obese CKD population, mortality was higher with loss of exercise habits (0.96%) than in those continuously maintaining exercise habits (0.52%). The age- and sex-adjusted hazard ratio for all-cause death was 2.23 in the group with weight gain compared to the group with stable weight (p<0.01) and 2.08 in the group with loss of exercise habits compared to those who maintained exercise habits (p<0.01). Conclusion This observational cohort study suggested that loss of exercise habits as well as weight gain of more than 1 kg/m2/year might worsen all-cause mortality in the obese CKD population.

Does Vitamin Supplementation Play a Role in Chronic Kidney Disease?

Although the role of vitamins in the human body is proven, guidelines for patients with chronic kidney disease (CKD) remain unclear. This narrative review summarizes the findings of 98 studies of CKD and the effects of vitamin D, B, C, A, E, and K supplementation on patients on dialysis for CKD, with the aim of summarizing the existing guidelines. The findings are promising, showing the potential effectiveness of vitamin supplementation with, for example, vitamins B, D, or C. However, recommendations are still ambiguous, especially in the case of vitamins A and K, due to the potential toxicity associated with higher doses for patients. Continued research is needed to rigorously evaluate the effectiveness and carefully consider the potential risks of some vitamin supplementation for patients with CKD.

An Exploratory Study on a New Method for Nutritional Status Assessment in Patients with Chronic Kidney Disease

Malnutrition is a risk factor for disease progression and poor prognosis in chronic kidney disease (CKD). However, the complexity of nutritional status assessment limits its clinical application. This study explored a new method of nutritional assessment in CKD (stage 1-5) patients using the Subjective Global Assessment (SGA) as the gold standard and evaluated its applicability. The kappa test was used to analyze the consistency of the Renal Inpatient Nutrition Screening Tool (Renal iNUT) with SGA and protein-energy wasting. Logistic regression analysis was used to analyze the risk factors of CKD malnutrition and calculate the prediction probability of multiple indicators combined for the diagnosis of CKD malnutrition. The receiver operating characteristic curve of the prediction probability was drawn to evaluate its diagnostic efficiency. A total of 161 CKD patients were included in this study. The prevalence of malnutrition according to SGA was 19.9%. The results showed that Renal iNUT had a moderate consistency with SGA and a general consistency with protein-energy wasting. Age > 60 years (odds ratio, OR = 6.78), neutrophil-lymphocyte ratio > 2.62 (OR = 3.862), transferrin < 200 mg/dL (OR = 4.222), phase angle < 4.5° (OR = 7.478), and body fat percentage < 10% (OR = 19.119) were risk factors for malnutrition in patients with CKD. The area under the receiver operating characteristic curve of multiple indicators for the diagnosis of CKD malnutrition was 0.89 (95% confidence interval: 0.834-0.946, p < 0.001). This study demonstrated that Renal iNUT has good specificity as a new tool for the nutrition screening of CKD patients, but its sensitivity needs to be optimized. Advanced age, high neutrophil-lymphocyte ratio, low transferrin level, low phase angle, and low body fat percentage are risk factors for malnutrition in patients with CKD. The combination of the above indicators has high diagnostic efficiency in the diagnosis of CKD malnutrition, which may be an objective, simple, and reliable method to evaluate the nutritional status of patients with CKD.

Non-insulin-based insulin resistance indices for predicting all-cause mortality and renal outcomes in patients with stage 1-4 chronic kidney disease: another paradox

Non-insulin-based insulin resistance (IR) indices serve as the indicators of metabolic syndrome (MetS) but have limited value for predicting clinical outcomes. Whether the obesity paradox affects the predictive value of these indicators in patients with chronic kidney disease (CKD) remains unknown. We investigated whether MetS and non-insulin-based IR indices can predict all-cause mortality and renal outcomes in a prospective observational study with stage 1-4 CKD Asians (N = 2,457). These IR indices were associated with MetS. A Cox regression model including body mass index (BMI) revealed an association between MetS and renal outcomes. Among the IR indices, only high triglyceride-glucose (TyG) index was associated with adverse renal outcomes: the hazard ratio of Q4 quartile of the TyG index was 1.38 (1.12-1.70). All-cause mortality was marginally associated with MetS but not high IR indices. Low TyG and TyG-BMI indices as well as low BMI and triglyceride were paradoxically associated with increased risks of clinical outcomes. The triglyceride-to-high-density lipoprotein cholesterol ratio and metabolic score for IR indices were not associated with clinical outcomes. In conclusion, MetS and TyG index predict renal outcome and obesity paradox affects the prediction of IR indices in patients with stage 1-4 CKD.

TME-targeted approaches of brain metastases and its clinical therapeutic evidence

The tumor microenvironment (TME), which includes both cellular and non-cellular elements, is now recognized as one of the major regulators of the development of primary tumors, the metastasis of which occurs to specific organs, and the response to therapy. Development of immunotherapy and targeted therapies have increased knowledge of cancer-related inflammation Since the blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier (BCB) limit immune cells from entering from the periphery, it has long been considered an immunological refuge. Thus, tumor cells that make their way "to the brain were believed to be protected from the body's normal mechanisms of monitoring and eliminating them. In this process, the microenvironment and tumor cells at different stages interact and depend on each other to form the basis of the evolution of tumor brain metastases. This paper focuses on the pathogenesis, microenvironmental changes, and new treatment methods of different types of brain metastases. Through the systematic review and summary from macro to micro, the occurrence and development rules and key driving factors of the disease are revealed, and the clinical precision medicine of brain metastases is comprehensively promoted. Recent research has shed light on the potential of TME-targeted and potential treatments for treating Brain metastases, and we'll use that knowledge to discuss the advantages and disadvantages of these approaches.

The new visceral adiposity index outperforms traditional obesity indices as a predictor of subclinical renal damage in Chinese individuals: a cross-sectional study

BACKGROUND

The new visceral adiposity index (NVAI) was superior to previous obesity indices in predicting cardiovascular diseases among Asians. Nevertheless, the utility of the NVAI for predicting chronic kidney disease is still unclear. The objective of this research was to explore the relationship between the NVAI and subclinical renal damage (SRD) and to investigate whether the NVAI outperforms other common obesity indices in predicting SRD in the Chinese population.

METHODS

Participants in this cross-sectional study were from the Hanzhong Adolescent Hypertension Cohort. The NVAI and seven other common obesity indices were calculated, including body mass index, waist circumference, lipid accumulation product, visceral adiposity index, Chinese visceral adiposity index, a body shape index and metabolic score for visceral fat. Logistic regression models revealed the association between NVAI and SRD. The odds ratio (OR) and the 95% confidence interval (CI) were calculated to show the association between the two variables. The predictive power of eight obesity indices for SRD was evaluated through the receiver operating characteristic curve and area under the curve (AUC). In addition, the net reclassification index (NRI) and integrated discrimination improvement (IDI) were also applied to compare the incremental predictive value for SRD of different obesity indices.

RESULTS

The median age of the 2358 subjects was 42.00 years. Across NVAI tertiles, the prevalence of SRD was 7.25%, 11.21%, and 21.60%, respectively. After adjusting for confounders, a high level of NVAI remained a risk factor for SRD. The ORs of the middle and top NVAI tertiles for SRD were 1.920 (95% CI: 1.322, 2.787) and 4.129 (95% CI: 2.750, 6.202), respectively. The AUC of the NVAI was 0.666 (95% CI: 0.647, 0.685), which was significantly larger than the AUC of any of the other obesity indicators. Moreover, the NRI and IDI were significantly improved when NVAI was added to the basic model for predicting SRD. Among eight obesity indices, NVAI had the highest NRI (0.392; 95% CI: 0.280, 0.503), and its IDI (0.021; 95% CI: 0.014, 0.027) was second only to that of the body mass index (0.023; 95% CI: 0.014, 0.032).

CONCLUSIONS

NVAI is independently and positively associated with SRD. Among the eight obesity indices, the NVAI shows the strongest predictive power for SRD in the Chinese population. The NVAI may be useful as an effective warning indicator of chronic kidney disease in Chinese adults.

An investigation of low-protein diets' qualification rates and an analysis of their short-term effects for patients with CKD stages 3-5: a single-center retrospective cohort study from China

BACKGROUND

The feasibility and efficacy of low-protein diets (LPD) treatment in chronic kidney disease (CKD) is controversial. Based on the characteristics of the Chinese diet, we observe the qualification rates and short-term clinical effects of LPD for CKD patients in our center.

METHODS

This is a retrospective cohort study. CKD stages 3-5 patients who were regularly followed up 5 times (over 2 years) and treated with LPD were included. We collected clinical data to observe the changes in LPD qualification rates and divided patients into LPD and non-LPD group according to the average dietary protein intake (DPI) of 5 follow-up time points and compared the changes in primary and secondary outcome measures between the two groups.

RESULTS

We analyzed data from 161 eligible CKD stages 3-5 patients. From baseline to the 5th follow-up time point, the LPD qualification rates of all patients were 11.80%, 35.40%, 47.82%, 53.43% and 54.04%, respectively. For primary outcome measures, the urine protein/creatinine ratio (UPCR) decreased more in the LPD group than in the non-LPD group [Median (interquartile range, IQR) of the difference between the 5th follow-up time point and baseline: 0.19 (- 0.01-0.73) vs. 0.10 (- 0.08-0.27), P < 0.001]. We constructed three classes of mixed linear models (model I, II, III). The UPCR slopes were all negative in the LPD group and positive in the non-LPD group (P < 0.001). Meanwhile, in model I, the estimate glomerular filtration rate(eGFR) decline slope in the LPD group was lower than that in the non-LPD group [slope (standard error): - 1.32 (0.37) vs. - 2.35 (0.33), P = 0.036]. For secondary outcome measures, body mass index (BMI) triglycerides (TG), body weight, and fat free mass (FFM) showed stable statistical differences in the comparison of LPD and non-LPD groups, with greater declines in the former.

CONCLUSION

The results of this study suggest that LPD treatment can reduce UPCR in patients with CKD stages 3-5, and may also delay the decline in eGFR. Meanwhile, it also reduces BMI, TG, body weight, and FFM, thus the need to prevent malnutrition in clinical implementation.

Dietary EPA+DHA Mitigate Hepatic Toxicity and Modify the Oxylipin Profile in an Animal Model of Colorectal Cancer Treated with Chemotherapy

Irinotecan (CPT-11) and 5-fluorouracil (5-FU) are commonly used to treat metastatic colorectal cancer, but chemotherapy-associated steatosis/steatohepatitis (CASSH) frequently accompanies their use. The objective of this study was to determine effect of CPT-11+5-FU on liver toxicity, liver oxylipins, and cytokines, and to explore whether these alterations could be modified by dietary eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the form of fish oil (EPA+DHA). Tumor-bearing animals were administered CPT-11+5-FU and maintained on a control diet or a diet containing EPA+DHA (2.3 g/100 g). Livers were collected one week after chemotherapy for the analysis of oxylipins, cytokines, and markers of liver pathology (oxidized glutathione, GSSH; 4-hydroxynonenal, 4-HNE, and type-I collagen fiber). Dietary EPA+DHA prevented the chemotherapy-induced increases in liver GSSH (p < 0.011) and 4-HNE (p < 0.006). Compared with the tumor-bearing animals, ten oxylipins were altered (three/ten n-6 oxylipins were elevated while seven/ten n-3 oxylipins were reduced) following chemotherapy. Reductions in the n-3 fatty-acid-derived oxylipins that were evident following chemotherapy were restored by dietary EPA+DHA. Liver TNF-α, IL-6 and IL-10 were elevated (p < 0.05) following chemotherapy; dietary EPA+DHA reduced IL-6 (p = 0.09) and eotaxin (p = 0.007) levels. Chemotherapy-induced liver injury results in distinct alterations in oxylipins and cytokines, and dietary EPA+DHA attenuates these pathophysiological effects.

Waist-hip ratio measured by bioelectrical impedance analysis as a valuable predictor of chronic kidney disease development

Obesity is a major health problem worldwide and is associated with chronic kidney disease (CKD). Body mass index (BMI) is a common method of diagnosing obesity, but there are concerns about its accuracy and ability to measure body composition. This study evaluated the risk of CKD development in a middle-aged population in association with various body composition metrics. From a prospective cohort of 10,030 middle-aged adults, we enrolled 6727 for whom baseline and follow-up data were available. We collected data pertaining to participants' BMI, manually measured waist-hip ratio (WHR), and various measurements of bioelectrical impedance analysis (BIA), including total body fat content, muscle content, and calculated WHR, and classified the participants into quintiles accordingly. CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m² in follow-up laboratory tests. While an increase in BMI, WHR, and total body fat were associated with an elevated risk of CKD, an increase in total body muscle decreased the risk. Among the body composition metrics, WHR measured by BIA had the highest predictive value for CKD (C-statistics: 0.615). In addition, participants who were "healthy overweight, (defined as low WHR but high BMI), exhibited a 62% lower risk of developing CKD compared to those with "normal-weight obesity," (defined as high WHR despite a normal BMI). In conclusion, we suggest that central obesity measured by BIA is a more accurate indicator than BMI for predicting the development of CKD.

Glomerular filtration rate abnormalities in sickle cell disease

Sickle cell disease (SCD) is a group of inherited blood disorders affecting the β-globin gene, resulting in the polymerization of hemoglobin and subsequent sickling of the red blood cell. Renal disease, the most common complication in SCD, begins in childhood with glomerular hyperfiltration and then progresses into albuminuria, a fast decline of glomerular filtration, and renal failure in adults. This mini-review focuses on glomerular filtration abnormalities and the mechanisms of hyperfiltration, explores genetic modifiers and methods of estimating glomerular filtration rates, and examines novel biomarkers of glomerular filtration in SCD.

Normal weight and waist obesity indicated by increased total body fat associated with all-cause mortality in stage 3–5 chronic kidney disease

Patients with chronic kidney disease (CKD) demonstrate a survival benefit with a high body mass index (BMI); this is the obesity paradox. Central obesity has a higher prognostic value than BMI, even in those with normal weight. Whether total body fat percentage (TBF%) provides more information than BMI and waist circumference (WC) remains unknown. We included 3,262 Asian patients with stage 3–5 CKD and divided these patients by TBF% and waist-to-height ratio (WHtR) quartiles (Q1–Q4). TBF% was associated with BMI, WC, nutritional markers, and C-reactive protein. In all patients, BMI but not TBF% or WHtR demonstrated a survival paradox. In patients with BMI &lt;25 kg/m2, but not in those with BMI ≥ 25 kg/m2, TBF% Q4 and WHtR Q4 were associated with all-cause mortality, with hazard ratios [HRs; 95% confidence intervals (CIs)] of 2.35 (1.31–4.22) and 1.38 (1.06–1.80), respectively. The HRs of TBF% Q4 for all-cause mortality were 2.90 (1.50–5.58) in patients with a normal WC and 3.81 (1.93–7.50) in patients with normal weight and normal WC (All P for interaction &lt; 0.05). In conclusion, TBF% can predict all-cause mortality in patients with advanced CKD and a normal weight, normal WC, or both.

The association between body mass index and all-cause mortality in Japanese patients with incident hemodialysis

Background

A higher body mass index (BMI) has been associated with better survival among chronic kidney disease patients in some reports. However, more research is required to determine the associations between BMI and mortality in incident hemodialysis patients. Therefore, this study aimed to investigate the association between mortality and BMI measured at the first hemodialysis session and 2 weeks after hemodialysis initiation in Japanese patients with incident hemodialysis.

Methods

We retrospectively enrolled 266 adult patients with incident hemodialysis who were treated at our hospital between May 2013 and June 2019. The data on BMI was obtained at the first hemodialysis session and 2 weeks after hemodialysis initiation. Patients were divided into tertiles based on BMI [<18.5 (low), 18.5–23.9 (normal), and ≥24 (high) kg/m2]. The normal group was used as the reference group. The primary outcome was all-cause mortality.

Results

The mean age of patient was 68.9 ± 12.0 years, and the BMI was 23.3 ± 4.24 kg/m2 at the first hemodialysis session. The body mass index was 22.0 ± 3.80 kg/m2 at 2 weeks after hemodialysis initiation. During a mean follow-up of 3.89 ± 2.12 years, 80 (30.1%) deaths occurred. In multivariate analyses, low BMI at the first hemodialysis session was significantly associated with worse all-cause mortality (hazard ratio, 2.39; 95% confidence interval, 1.13–5.03). At 2 weeks after hemodialysis initiation, high BMI was significantly associated with better all-cause mortality (hazard ratio, 0.38; 95% confidence interval, 0.18–0.81).

Conclusion

At 2 weeks after HD initiation, high BMI was associated with lower mortality in Japanese patients with incident hemodialysis.

Association between Body Mass Index and Renal Outcomes Modified by Chronic Kidney Disease and Anemia: The Obesity Paradox for Renal Outcomes

Obesity-related nephropathy is associated with renal function progression. However, some studies have associated a high body mass index (BMI) with improved renal outcomes—this is referred to as the obesity paradox for renal outcomes, especially in relation to advanced chronic kidney disease (CKD). Central obesity can explain the obesity paradox in all-cause mortality. However, whether obesity or central obesity is associated with renal outcomes (renal replacement therapy or a 50% decline in the estimated glomerular filtration rate) in patients with advanced CKD remains unclear. Our study included 3605 Asian patients with CKD stages 1−5 divided into six groups according to their BMI (between 15 and 35 kg/m2). Through linear regression, BMI was positively associated with hemoglobin and albumin at CKD stages 4 and 5. In the competing risk Cox regression model, a high BMI (27.5−35 kg/m2) was associated with renal outcomes at CKD stages 1−3, but not stages 4 and 5. A high BMI was associated with renal outcomes in patients with hemoglobin ≥11 g/dL, but not <11 g/dL. A high waist-to-hip ratio was not associated with renal outcomes. We conclude that the CKD stage and anemia may explain the obesity paradox in renal outcomes in patients with CKD.

Joint latent class trees: A tree-based approach to modeling time-to-event and longitudinal data

In this paper, we propose a semiparametric, tree-based joint latent class model for the joint behavior of longitudinal and time-to-event data. Existing joint latent class approaches are parametric and can suffer from high computational cost. The most common parametric approach, the joint latent class model, further restricts analysis to using time-invariant covariates in modeling survival risks and latent class memberships. The proposed tree method (joint latent class tree) is fast to fit, and permits time-varying covariates in all of its modeling components. We demonstrate the prognostic value of using time-varying covariates, and therefore the advantage of joint latent class tree over joint latent class model on simulated data. We apply joint latent class tree to a well-known data set (the PAQUID data set) and confirm its superior prediction performance and orders-of-magnitude speedup over joint latent class model.

Renal Function Effect on the Association Between Body Mass Index and Mortality Risk After Acute Myocardial Infarction

Background: Body mass index (BMI) is a critical determinant of mortality after acute myocardial infarction (AMI), and higher BMI is associated with survival benefit in patients with renal impairment. However, there are no studies investigating the interactive effects of BMI and renal function on mortality risk after AMI occurrence. Methods: We enrolled 12,647 AMI patients from Korea Acute Myocardial Infarction Registry between November 2011 and December 2015. Patients were categorized based on estimated Glomerular Filtration Rate (eGFR) and BMI. The primary endpoint was all-cause mortality after AMI treatment. Results: Within each renal function category, the absolute mortality rate was decreased in patients with higher BMI. However, the adjusted hazard ratio (HR) of all-cause mortality for higher BMI was decreased as renal function worsened [adjusted HR (95% confidence interval) at BMI ≥ 25 kg/m²: 0.63 (0.41-0.99), 0.76 (0.59-0.97), and 0.84 (0.65-1.08) for patients with eGFR ≥ 90, 90-45, and <45 mL/min/1.73 m², respectively]. There was a significant interaction between BMI and renal function (P for interaction = 0.010). The protective effect of higher BMI was preserved against non-cardiac death and it was also decreased with lowering eGFR in competing risks models [adjusted HR at BMI ≥25 kg/m²: 0.38 (0.18-0.83), 0.76 (0.59-0.97), and 0.84 (0.65-1.08) for patients with eGFR ≥ 90, 90-45, and <45 mL/min/1.73 m², respectively; P for interaction = 0.03]. However, renal function did not significantly affect the association between BMI and risk of cardiac death (P for interaction = 0.20). Conclusions: The effect of BMI on the mortality risk after AMI was dependent on renal function. The association between greater BMI and survival benefit was weakened as renal function was decreased. In addition, the negative effect of renal function on the BMI - mortality association was pronounced in the non-cardiac death.

U-Shaped Association between Waist-to-Hip Ratio and All-Cause Mortality in Stage 3-5 Chronic Kidney Disease Patients with Body Mass Index Paradox

The obesity paradox, referring to the association of high body mass index (BMI) with low all-cause mortality risk, is found in patients with chronic kidney disease (CKD). Central obesity is associated with metabolic syndrome and may have better prognostic value than BMI for all-cause mortality. Whether central obesity is associated with all-cause mortality in cases of obesity paradox in CKD patients remains unknown. We included 3262 patients with stage 3–5 CKD, grouped into five quintiles (Q1–5) by waist-to-hip ratio (WHR). Low WHR and BMI were associated with malnutrition and inflammation. In Cox regression, high BMI was not associated with all-cause mortality, but BMI < 22.5 kg/m² increased the mortality risk. A U-shaped association between central obesity and all-cause mortality was found: WHR Q1, Q4, and Q5 had higher risk for all-cause mortality. The hazard ratio (95% confidence interval) of WHR Q5 and Q1 for all-cause mortality was 1.39 (1.03–1.87) and 1.53 (1.13–2.05) in male and 1.42 (1.02–1.99) and 1.28 (0.88–1.85) in female, respectively. Waist-to-height ratio and conicity index showed similar results. Low WHR or low BMI and high WHR, but not high BMI, are associated with all-cause mortality in advanced CKD.

The obesity paradox and hypoglycemia in critically ill patients

BACKGROUND

A high body mass index (BMI) has been associated with decreased mortality in critically ill patients. This association may, in part, relate to the impact of BMI on glycemia. We aimed to study the relationship between BMI, glycemia and hospital mortality.

METHODS

We included all patients with a recorded BMI from four large international clinical databases (n = 259,177). We investigated the unadjusted association of BMI with average glucose levels, mortality and hypoglycemia rate. We applied multivariate analysis to investigate the impact of BMI on hypoglycemia rate, after adjusting for glycemia-relevant treatments (insulin, dextrose, corticosteroids, enteral and parenteral nutrition) and key physiological parameters (previous blood glucose level, blood lactate, shock state, SOFA score).

RESULTS

We analyzed 5,544,366 glucose measurements. On unadjusted analysis, increasing BMI was associated with increasing glucose levels (average increase of 5 and 10 mg/dL for the 25-30, 30-35 kg/m2 BMI groups compared to normal BMI (18.5-25 kg/m2) patients). Despite greater hyperglycemia, increasing BMI was associated with lower hospital mortality (average decrease of 2% and 3.25% for the 25-30, 30-35 kg/m2 groups compared to normal BMI patients) and lower hypoglycemia rate (average decrease of 2.5% and 3.5% for the 25-30, 30-35 kg/m2 groups compared to normal BMI patients). Increasing BMI was significantly independently associated with reduced hypoglycemia rate, with odds ratio (OR) 0.72 and 0.65, respectively (95% CIs 0.67-0.77 and 0.60-0.71, both p < 0.001) when compared with normal BMI. Low BMI patients showed greater hypoglycemia rate, with OR 1.6 (CI 1.43-1.79, p < 0.001). The association of high BMI and decreased mortality did not apply to diabetic patients. Although diabetic patients had higher rates of hypoglycemia overall and higher glucose variability (p < 0.001), they also had a reduced risk of hypoglycemia with higher BMI levels (p < 0.001).

CONCLUSIONS

Increasing BMI is independently associated with decreased risk of hypoglycemia. It is also associated with increasing hyperglycemia and yet with lower mortality. Lower risk of hypoglycemia might contribute to decreased mortality and might partly explain the obesity paradox. These associations, however, were markedly modified by the presence of diabetes.

Combination of Thigh Circumference and Indices of Central Obesity Helps Predict Incident Chronic Kidney Disease: A 14-Year Prospective Cohort Study Using a Three-Dimensional Body Laser Scanner

OBJECTIVE

Obesity, high body mass index, and visceral fat accumulation are associated with renal diseases. However, the association between body measurements and chronic kidney disease (CKD) is still unclear.

METHODS

A cohort of 7,825 participants scheduled for follow-up of CKD was recruited from 2000 to 2008 in Taiwan. A questionnaire was developed to collect the basic demographics, lifestyle variables, personal disease history, and family disease history of the participants. A 3-dimensional body surface scanning system was used to take their body measurements. The participants underwent an average follow-up of 14.3 years for evaluation of the incidence of CKD. A multiple Cox regression model was built.

RESULTS

Three body measurements, namely chest width (hazard ratio [HR] 1.059, 95% confidence interval [CI] 1.011-1.110), waist circumference (HR 1.017, 95% CI 1.006-1.029), and thigh circumference (HR 0.941, 95% CI 0.922-0.961), were significantly associated with CKD. Two combinations of body measurements, namely the waist-to-thigh ratio and chest-to-thigh ratio, were derived to predict the occurrence of CKD. Participants with the highest quartile of waist-to-thigh ratio and chest-to-thigh ratio had a 2.175-fold and 2.182-fold risk of developing CKD, respectively.

CONCLUSIONS

This study suggests that along with central obesity, body limb measurements can be used as an indicator to predict the occurrence of CKD. The effects of limb measurements on CKD could help provide an innovative perspective regarding the intervention to be developed for the treatment of CKD and a preventive medicine for high-risk individuals. The association of thigh circumference with CKD warrants further investigation.

Significance of Adipose Tissue Maintenance in Patients Undergoing Hemodialysis

In the general population, obesity is known to be associated with adverse outcomes, including mortality. In contrast, high body mass index (BMI) may provide a survival advantage for hemodialysis patients, which is known as the obesity paradox. Although BMI is the most commonly used measure for the assessment of obesity, it does not distinguish between fat and lean mass. Fat mass is considered to serve as an energy reserve against a catabolic condition, while the capacity to survive starvation is also thought to be dependent on its amount. Thus, fat mass is used as a nutritional marker. For example, improvement of nutritional status by nutritional intervention or initiation of hemodialysis is associated with an increase in fat mass. Several studies have shown that higher levels of fat mass were associated with better survival in hemodialysis patients. Based on body distribution, fat mass is classified into subcutaneous and visceral fat. Visceral fat is metabolically more active and associated with metabolic abnormalities and inflammation, and it is thus considered to be a risk factor for cardiovascular disease and mortality. On the other hand, subcutaneous fat has not been consistently linked to adverse phenomena and may reflect nutritional status as a type of energy storage. Visceral and subcutaneous adipose tissues have different metabolic and inflammatory characteristics and may have opposing influences on various outcomes, including mortality. Results showing an association between increased subcutaneous fat and better survival, along with other conditions, such as cancer or cirrhosis, in hemodialysis patients have been reported. This evidence suggests that fat mass distribution (i.e., visceral fat and subcutaneous fat) plays a more important role for these beneficial effects in hemodialysis patients.

Dexamethasone Conjugates: Synthetic Approaches and Medical Prospects

Dexamethasone (DEX) is the most commonly prescribed glucocorticoid (GC) and has a wide spectrum of pharmacological activity. However, steroid drugs like DEX can have severe side effects on non-target organs. One strategy to reduce these side effects is to develop targeted systems with the controlled release by conjugation to polymeric carriers. This review describes the methods available for the synthesis of DEX conjugates (carbodiimide chemistry, solid-phase synthesis, reversible addition fragmentation-chain transfer [RAFT] polymerization, click reactions, and 2-iminothiolane chemistry) and perspectives for their medical application as GC drug or gene delivery systems for anti-tumor therapy. Additionally, the review focuses on the development of DEX conjugates with different physical-chemical properties as successful delivery systems in the target organs such as eye, joint, kidney, and others. Finally, polymer conjugates with improved transfection activity in which DEX is used as a vector for gene delivery in the cell nucleus have been described.

Body mass index as a predictor of mortality in bronchiectasis: A nationwide population-based study

INTRODUCTION

The prognosis of bronchiectasis is not well known. The purpose of this study was to evaluate the association between body mass index (BMI) and mortality in bronchiectasis using a large nationwide population-based cohort.

MATERIAL AND METHODS

Using the National Health Insurance Service-Health Screening Cohort in Korea, individuals with bronchiectasis were identified from 2004 to 2006 and monitored for up to 10 years. Mortality in bronchiectasis was analyzed based on a BMI score <18.5 kg/m² (underweight), 1.85-22.9 kg/m² (normal weight), 23.0-24.9 kg/m² (overweight), and >25.0 kg/m² (obese).

RESULTS

A total of 2769 individuals with bronchiectasis were included. The underweight, normal weight, overweight, and obese accounted for 5.1%, 40.4%, 25.4%, and 29.3% of all patients with bronchiectasis, respectively. Compared to normal weight, underweight in bronchiectasis was associated with increased all-cause mortality (hazard ratio [HR] = 2.60; 95% confidence interval [CI] = 1.92-3.54), while obese was associated with decreased all-cause mortality (HR = 0.71; 95% CI = 0.55-0.93). This relationship between BMI and mortality was more prominent in respiratory disease-related mortality.

CONCLUSIONS

BMI is a predictor of mortality in bronchiectasis. Underweight is associated with increased mortality among individuals with bronchiectasis while obese is associated with decreased mortality.

Incremental Effect of Aging on Obesity-Related Incident Chronic Kidney Disease in the Korean General Population

OBJECTIVES

Obesity may increase the risk of kidney function decline. However, few studies have addressed how age modifies obesity-associated risk of chronic kidney disease (CKD) in the Asian general population.

DESIGN

A community-based prospective cohort study.

SETTING AND PARTICIPANTS

6538 Korean general population with normal kidney function from the Korean Genome and Epidemiology Study Database.

METHODS

Participants were stratified according to age (40-49, 50-59, and 60-69 years old) and body mass index [≥18.5-<23 (normal-weight), ≥23-<27.5 (overweight), and ≥27.5 (obese)]. We conducted Kaplan-Meier and multivariable-adjusted Cox regression analyses to investigate the association of aging and obesity with incident CKD.

RESULTS

During the 12-year follow-up, an overall incidence rate of CKD was 6.1 cases per 1000 person-years. Obese, but not overweight, people had an increased risk of incident CKD compared with normal-weight people in multivariable models adjusted for metabolic factors. When analyzed by 10-year increments, this association was significant only in 60-69-year-old individuals. Kaplan-Meier analysis showed that the incidence of CKD associated with overweight or obesity showed an accentuated increase with age. With reference to normal-weight individuals aged 40-49 years, the adjusted hazard ratio of CKD increased with age regardless of body mass index, and the positive association between obesity and incident CKD was more prominent with increasing age.

CONCLUSIONS AND IMPLICATIONS

Obesity-associated risk of incident CKD was accentuated in older people, and this association was independent of metabolic abnormalities.

Abdominal adiposity assessed using CT angiography associates with acute kidney injury after trans-catheter aortic valve replacement

AIM

To determine if there is an association between area-based visceral abdominal adipose tissue (VAT), subcutaneous abdominal adipose tissue (SAT), and abdominal circumference measured on computed tomography (CT) angiography before trans-catheter aortic valve replacement (TAVR) and post-TAVR acute kidney injury (AKI).

MATERIALS AND METHODS

In this retrospective cohort study of 106 TAVR patients, SAT and VAT areas and abdominal circumference was measured on a single CT section at L4 vertebral level. Univariate comparisons between patients who did and did not develop AKI were undertaken for radiological measurements. Multivariable logistic regression was used to assess association between CT measurements and the development of post-TAVR AKI.

RESULTS

Post-TAVR AKI occurred in 20 of 106 patients (19%). In univariate comparisons, body mass index (BMI) did not differ significantly between patients who did and did not develop AKI (p=0.14); however, VAT+SAT (443.2±163.7 versus 351±168.7 cm²; p=0.03), VAT (213.9±110.6 versus 153.9±96.1 cm²; p=0.03), and outer abdominal circumference (100.2±14.4 cm versus 91.8±13.3 cm; p=0.02) were significantly higher in the patients who did not develop post-TAVR AKI. These three measures on pre-TAVR CT angiogram remained significantly associated with reduced post-TAVR AKI with a lower incidence of post-TAVR AKI after multivariable adjustment for pre-TAVR estimated glomerular filtration rate and patient height (p<0.05).

CONCLUSION

This study found that increased abdominal obesity as assessed by measures on pre-TAVR CT angiogram is associated with a significantly lower incidence of AKI.

Adiposity, Physical Function, and Their Associations With Insulin Resistance, Inflammation, and Adipokines in CKD

RATIONALE & OBJECTIVES

Adiposity and physical fitness levels are major drivers of cardiometabolic risk, but these relationships have not been well-characterized in chronic kidney disease (CKD). We examined the associations of visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), intrahepatic fat, and physical function with inflammation, insulin resistance, and adipokine levels in patients with CKD.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

Participants with stages 3-5 CKD not receiving maintenance dialysis, followed up at one of 8 clinical sites in the Chronic Renal Insufficiency Cohort (CRIC) Study, and who underwent magnetic resonance imaging of the abdomen at an annual CRIC Study visit (n = 419).

PREDICTORS

VAT volume, SAT volume, intrahepatic fat, body mass index, waist circumference, and time taken to complete the 400-m walk test (physical function).

OUTCOMES

Markers of inflammation (interleukin 1β [IL-1β], IL-6, tumor necrosis factor receptor 1 [TNFR1], and TNFR2), insulin resistance (homeostasis model assessment of insulin resistance), and adipokine levels (adiponectin, total and high molecular weight, resistin, and leptin).

ANALYTICAL APPROACH

Multivariable linear regression of VAT and SAT volume, intrahepatic fat, and physical function with individual markers (log-transformed values), adjusting for relevant covariates.

RESULTS

Mean age of the study population was 64.3 years; 41% were women, and mean estimated glomerular filtration rate was 53.2±14.6 (SD) mL/min/1.73m². More than 85% were overweight or obese, and 40% had diabetes. Higher VAT volume, SAT volume, and liver proton density fat fraction were associated with lower levels of total and high-molecular-weight adiponectin, higher levels of leptin and insulin resistance, and lower high-density lipoprotein cholesterol and higher serum triglyceride levels. A slower 400-m walk time was associated only with higher levels of leptin, total adiponectin, plasma IL-6, and TNFR1 and did not modify the associations between fat measures and cardiometabolic risk factors.

LIMITATIONS

Lack of longitudinal data and dietary details.

CONCLUSIONS

Various measures of adiposity are associated with cardiometabolic risk factors. Physical function was also associated with the cardiometabolic risk factors studied and does not modify associations between fat measures and cardiometabolic risk factors. Longitudinal studies of the relationship between body fat and aerobic fitness with cardiovascular and kidney disease progression are warranted.

Association of Body Mass Index and Waist Circumference with All-Cause Mortality in Hemodialysis Patients

In this study based on a large nationally representative sample of Korean adults, we investigated the potential associations of the body mass index (BMI) and waist circumference (WC) with mortality in patients undergoing hemodialysis. We obtained the data of 18,699 participants >20 years of age who were followed up with for 4 years and for whom BMI and WC information were available, using a nationally representative dataset from the Korean National Health Insurance System. Patients were stratified into five levels by their baseline BMI and into six levels by their WC (5-cm increments). A total of 4975 deaths occurred during a median follow-up period of 48.2 months. Participants with a higher BMI had a lower mortality rate than those with a lower BMI. In a fully adjusted Cox regression analysis, being overweight and obese was associated with a significantly lower relative risk of all-cause mortality relative to the reference group. Conversely, the mortality rate was higher among participants with a high WC than among those with a low WC. Participants with the highest WC had a higher risk of mortality, while those with the lowest WC level had a significantly lower risk of mortality. In conclusion, all-cause mortality was positively associated with WC, a measure of abdominal obesity, and inversely associated with BMI, a measure of body volume, in patients undergoing hemodialysis.

Effects of Rikkunshito treatment on renal fibrosis/inflammation and body weight reduction in a unilateral ureteral obstruction model in mice

Chronic kidney disease (CKD) progresses to end-stage renal failure via renal tubulointerstitial fibrosis. Malnutrition, inflammation, and arteriosclerosis interact to exacerbate the poor prognosis of CKD, and their effective management is thus essential. The traditional Japanese medicine Rikkunshito (RKT) exerts appetite-stimulating effects via ghrelin, which attenuates inflammation and fibrosis. We evaluated the therapeutic effect of RKT in unilateral ureter obstruction (UUO)-induced renal fibrosis/inflammation and body weight loss in mice. UUO and sham-operated mice were fed a standard diet or diet containing 3.0% RKT. Renal fibrosis was investigated by histopathology and macrophage infiltration was determined by immunohistochemistry. Expression levels of genes associated with fibrosis, inflammation, ghrelin, and mitochondrial function were determined by quantitative reverse transcription-polymerase chain reaction and western blot analyses. RKT treatment partially prevented UUO-induced weight loss but failed to attenuate renal fibrosis and inflammation. Renal expression of sirtuin 1, a ghrelin-downstream signalling molecule, and gene expression of peroxisome proliferator-activated receptor-γ coactivator 1α and Bcl-2/adenovirus E1B interacting protein 3 were unaffected by RKT. These results indicate that RKT inhibits weight loss but does not improve renal fibrosis or inflammation in a rapidly progressive renal fibrosis mouse model. RKT may have a protective effect on weight loss associated with CKD.

Nonlinear and time-dependent effects of sparsely measured continuous time-varying covariates in time-to-event analysis

Many flexible extensions of the Cox proportional hazards model incorporate time-dependent (TD) and/or nonlinear (NL) effects of time-invariant covariates. In contrast, little attention has been given to the assessment of such effects for continuous time-varying covariates (TVCs). We propose a flexible regression B-spline-based model for TD and NL effects of a TVC. To account for sparse TVC measurements, we added to this model the effect of time elapsed since last observation (TEL), which acts as an effect modifier. TD, NL, and TEL effects are estimated with the iterative alternative conditional estimation algorithm. Furthermore, a simulation extrapolation (SIMEX)-like procedure was adapted to correct the estimated effects for random measurement errors in the observed TVC values. In simulations, TD and NL estimates were unbiased if the TVC was measured with a high frequency. With sparse measurements, the strength of the effects was underestimated but the TEL estimate helped reduce the bias, whereas SIMEX helped further to correct for bias toward the null due to "white noise" measurement errors. We reassessed the effects of systolic blood pressure (SBP) and total cholesterol, measured at two-year intervals, on cardiovascular risks in women participating in the Framingham Heart Study. Accounting for TD effects of SBP, cholesterol and age, the NL effect of cholesterol, and the TEL effect of SBP improved substantially the model's fit to data. Flexible estimates yielded clinically important insights regarding the role of these risk factors. These results illustrate the advantages of flexible modeling of TVC effects.

Association of Body Mass Index and Outcome in Acutely Ill Patients With Chronic Kidney Disease Requiring Intensive Care Therapy

OBJECTIVE

An association of body mass index (BMI) and outcome, the "obesity paradox," has been described in patients with chronic kidney disease (CKD) and end-stage renal disease. We sought to assess whether a potential beneficial effect of a high body mass is also seen in CKD patients with critical illness.

METHODS

In a retrospective analysis of a prospectively collected database of 123,416 patients from 107 Austrian intensive care units (ICUs) in whom BMI was available, the association of 6 groups of BMI and hospital mortality was assessed in 12,206 patients with CKD 3-5 by univariate and multivariate logistic regression analyses.

RESULTS

Patients with CKD were sicker, had a longer ICU stay, and had a higher ICU and hospital mortality than those without. The association of BMI and outcome in CKD patients indicated a U-shaped curve with the highest mortality in patients with BMI <20 and ≥40, and the lowest with a BMI between ≥25 and <40. This relationship was also significant in a multivariate analysis adjusted for severity of illness assessed by Simplified Acute Physiology Score III score, age, gender, admission diagnosis, and pre-existing comorbidities. It was not found in patients with CKD 5 on renal replacement therapy, in patients below 60 years of age, and those with diabetes mellitus requiring insulin treatment.

CONCLUSIONS

BMI is associated with better outcomes in CKD 3-5 patients who have acquired acute intermittent diseases and are admitted to an ICU, but not those requiring renal replacement therapy. This higher tolerance to acute disease processes may in part explain the "obesity paradox" observed in CKD patients.

Chronic Kidney Disease and the Adiposity Paradox: Valid or Confounded?

OBJECTIVE

Obesity, defined by body mass index (BMI), is associated with lower mortality risk in patients with chronic kidney disease (CKD). BMI and % body fat (%BF) are confounded by muscle mass, while DXA derived fat mass index (FMI) overcomes this limitation. We compared the associations between obesity and mortality in persons with CKD using multiple estimates of adiposity, and determined whether muscle mass, inflammation and weight loss modify these associations.

METHODS

Obesity was defined using BMI and DXA-derived FMI and %BF cut-offs in 2,852 NHANES participants with CKD from 1999-2006 and linked to the National Death Index with follow up through 2011. Cox proportional hazards models assessed associations between mortality and measures of obesity.

RESULTS

Obesity based on FMI and continuous variables, FMI, BMI and %BF were associated with lower mortality. The protective association of obesity was less pronounced among participants with higher muscle mass and was no longer significant after adjustment for prior weight loss. Inflammation did not modify these associations.

CONCLUSIONS

We observed lower mortality associated with higher fat mass, particularly among persons with lower muscle mass. The prevalence of >10% weight loss was half as common among obese compared to non-obese participants and confounded these associations.

BMI and its association with death and the initiation of renal replacement therapy (RRT) in a cohort of patients with chronic kidney disease (CKD)

BACKGROUND

A survival advantage associated with obesity has often been described in dialysis patients. The association of higher body mass index (BMI) with mortality and renal replacement therapy (RRT) in preterminal chronic kidney disease (CKD) patients has not been established.

METHODS

Subjects were patients with pre-terminal CKD who were recruited to the CKD.QLD registry. BMI at time of consent was grouped as normal (BMI 18.5-24.9 kg/m2), overweight (BMI 25-29.9 kg/m2), mild obesity (BMI 30-34.9 kg/m2) and moderate obesity+ (BMI ≥ 35 kg/m2) as defined by WHO criteria. The associations of BMI categories with mortality and starting RRT were analysed.

RESULTS

The cohort consisted of 3344 CKD patients, of whom 1777 were males (53.1%). The percentages who had normal BMI, or were overweight, mildly obese and moderately obese+ were 18.9, 29.9, 25.1 and 26.1%, respectively. Using people with normal BMI as the reference group, and after adjusting for age, socio-economic status, CKD stage, primary renal diagnoses, comorbidities including cancer, diabetes, peripheral vascular disease (PVD), chronic lung disease, coronary artery disease (CAD), and all other cardiovascular disease (CVD), the hazard ratios (HRs, 95% CI) of males for death without RRT were 0.65 (0.45-0.92, p = 0.016), 0.60 (0.40-0.90, p = 0.013), and 0.77 (0.50-1.19, p = 0.239) for the overweight, mildly obese and moderately obese+. With the same adjustments the hazard ratios for death without RRT in females were 0.96 (0.62-1.50, p = 0.864), 0.94 (0.59-1.49, p = 0.792) and 0.96 (0.60-1.53, p = 0.865) respectively. In males, with normal BMI as the reference group, the adjusted HRs of starting RRT were 1.15 (0.71-1.86, p = 0.579), 0.99 (0.59-1.66, p = 0.970), and 0.95 (0.56-1.61, p = 0.858) for the overweight, mildly obese and moderately obese+ groups, respectively, and in females they were 0.88 (0.44-1.76, p = 0.727), 0.94 (0.47-1.88, p = 0.862) and 0.65 (0.33-1.29, p = 0.219) respectively.

CONCLUSIONS

More than 80% of these CKD patients were overweight or obese. Higher BMI seemed to be a significant "protective" factor against death without RRT in males but there was not a significant relationship in females. Higher BMI was not a risk factor for predicting RRT in either male or female patients with CKD.

Sarcopenia and relationships between muscle mass, measured glomerular filtration rate and physical function in patients with chronic kidney disease stages 3-5

Background

Sarcopenia and poor physical function are common in patients with chronic kidney disease (CKD). Our aim was to investigate the relationships between muscle mass and measured glomerular filtration rate (GFR) and between muscle mass and strength and balance, respectively, in patients with CKD stages 3-5.

Methods

This is a baseline data analysis of a randomized controlled clinical trial. A total of 148 adult patients with an estimated GFR <30 mL/min/1.72 m2, not on renal replacement therapy, irrespective of the number of comorbidities were included from the Department of Nephrology, Skåne University Hospital, Lund, from 2011 to 2016. Body composition was measured by dual-energy X-ray absorptiometry (DEXA). GFR was measured by iohexol clearance. Balance was measured by functional reach and the Berg balance test and strength by handgrip strength and isometric quadriceps strength.

Results

Measured GFR ranged from 8 to 55 mL/min/1.73 m2. Lean mass (P < 0.05), fat mass (P < 0.05), appendicular skeletal muscle (P < 0.001) and appendicular skeletal muscle index (P < 0.05) were associated with GFR. Functional reach was associated with leg lean mass (P < 0.05) and the Berg balance test score was associated with trunk lean mass (P < 0.05). Handgrip strength was associated with arm lean mass (P < 0.001). Isometric quadriceps strength was associated with leg lean mass (P < 0.001). More men (44%) suffered from low muscle mass than women (22%), whereas more women (36%) suffered from low muscle strength than men (26%). However, when combining both, men (16%) suffered from sarcopenia to a greater extent than women (8%).

Conclusions

Among patients with CKD stages 3-5, loss of lean body mass, especially appendicular skeletal muscle, was significantly related to GFR decline. Two important markers of physical function, balance and strength, were significantly related to muscle mass. Moreover, men were more prone to sarcopenia than women during kidney function decline.

Oxidative Imbalance and Kidney Damage in Cafeteria Diet-Induced Rat Model of Metabolic Syndrome: Effect of Bergamot Polyphenolic Fraction

Obesity is a potent risk factor for kidney disease as it increases the possibility of developing diabetes and hypertension, and it has a direct impact on the development of chronic kidney disease and end-stage renal disease. In this study, we tested the effect of bergamot polyphenolic fraction in a cafeteria with diet-fed rats, an excellent experimental model for studying human metabolic syndrome, as it is able to induce severe obesity with insulin resistance and high plasma triglyceride levels more efficiently than a traditional lard-based high-fat diet used in rodent models. We analyzed the plasmatic oxidative balance by photometric tests, and the expression of cytoplasmic antioxidant enzymes (superoxide dismutase 1 and glutatione S-tranferasi P1) and apoptotic markers (Caspase 8 and 9) in kidney tissues by Western blot analysis. Our results clearly showed that the cafeteria diet induces a marked pro-oxidant effect: significant reduction of plasmatic antioxidant capacity; downregulation of cytoplasmic antioxidant enzymes expression; and activation of apoptotic pathways. All these hallmarks of redox disequilibrium were mitigated by treatment with polyphenolic fraction of bergamot, highlighting its antioxidant effect in the metabolic syndrome. Our data show that the link between obesity and renal damage could be represented by oxidative stress.

Cardiovascular Disease and Diabetic Kidney Disease

Diabetic kidney disease commonly is associated with an increased risk of cardiovascular disease. There are traditional common risk factors for both conditions including hypertension and poor glycemic control. However, it is likely that there are other pathophysiological mechanisms that explain the clinical phenomenon of increased cardiovascular disease in diabetic patients with chronic kidney and vice versa. Current management of both conditions includes aggressive glucose and blood pressure control. The protective role of treating dyslipidemia has been shown for cardiovascular disease, but the results for renal disease are not as clear. The advent of new classes of glucose-lowering agents such as sodium glucose co-transporter2 inhibitors and glucagon-like peptide-1 agonists has resulted in impressive effects on both cardiovascular and renal disease in diabetes. However, how these drugs act independently of glucose lowering to confer both kidney and cardiovascular protection has not been fully elucidated. Nevertheless, these new treatments provide optimism for reducing both microvascular and macrovascular complications in diabetes, which represent the major causes of morbidity and premature mortality in this condition.

Adiposity and risk of decline in glomerular filtration rate: meta-analysis of individual participant data in a global consortium

OBJECTIVE

To evaluate the associations between adiposity measures (body mass index, waist circumference, and waist-to-height ratio) with decline in glomerular filtration rate (GFR) and with all cause mortality.

DESIGN

Individual participant data meta-analysis.

SETTING

Cohorts from 40 countries with data collected between 1970 and 2017.

PARTICIPANTS

Adults in 39 general population cohorts (n=5 459 014), of which 21 (n=594 496) had data on waist circumference; six cohorts with high cardiovascular risk (n=84 417); and 18 cohorts with chronic kidney disease (n=91 607).

MAIN OUTCOME MEASURES

GFR decline (estimated GFR decline ≥40%, initiation of kidney replacement therapy or estimated GFR <10 mL/min/1.73 m²) and all cause mortality.

RESULTS

Over a mean follow-up of eight years, 246 607 (5.6%) individuals in the general population cohorts had GFR decline (18 118 (0.4%) end stage kidney disease events) and 782 329 (14.7%) died. Adjusting for age, sex, race, and current smoking, the hazard ratios for GFR decline comparing body mass indices 30, 35, and 40 with body mass index 25 were 1.18 (95% confidence interval 1.09 to 1.27), 1.69 (1.51 to 1.89), and 2.02 (1.80 to 2.27), respectively. Results were similar in all subgroups of estimated GFR. Associations weakened after adjustment for additional comorbidities, with respective hazard ratios of 1.03 (0.95 to 1.11), 1.28 (1.14 to 1.44), and 1.46 (1.28 to 1.67). The association between body mass index and death was J shaped, with the lowest risk at body mass index of 25. In the cohorts with high cardiovascular risk and chronic kidney disease (mean follow-up of six and four years, respectively), risk associations between higher body mass index and GFR decline were weaker than in the general population, and the association between body mass index and death was also J shaped, with the lowest risk between body mass index 25 and 30. In all cohort types, associations between higher waist circumference and higher waist-to-height ratio with GFR decline were similar to that of body mass index; however, increased risk of death was not associated with lower waist circumference or waist-to-height ratio, as was seen with body mass index.

CONCLUSIONS

Elevated body mass index, waist circumference, and waist-to-height ratio are independent risk factors for GFR decline and death in individuals who have normal or reduced levels of estimated GFR.

Clinical and metabolomic risk factors associated with rapid renal function decline in sickle cell disease

Sickle cell disease (SCD) nephropathy and lower estimated glomerular filtration rate (eGFR) are risk factors for early mortality. Furthermore, rate of eGFR decline predicts progression to end-stage renal disease in many clinical settings. However, factors predicting renal function decline in SCD are poorly documented. Using clinical, laboratory, genetic, and metabolomic data, we evaluated predictors of renal function decline in a longitudinal cohort of 288 adults (mean age 33.0 years). In 193 subjects with 5-year follow-up data, mean rate of eGFR decline was 2.35 mL/min/1.73 m² /year, nearly twice that of African American adults overall. Hyperfiltration was prevalent at baseline (61.1%), and 36.8% of subjects experienced rapid eGFR decline (≥3 mL/min/1.73 m² /year). Severe Hb genotype; proteinuria; higher platelet and reticulocyte counts, and systolic BP; and lower Hb level and BMI were associated with rapid decline. A risk scoring system was created using these 7 variables and was highly predictive of rapid eGFR decline, with odds of rapid decline increasing 1.635-fold for every point increment (P < 0.0001). Rapid eGFR decline was also associated with higher organ system severity score and peak creatinine. Additionally, two metabolites (asymmetric dimethylarginine and quinolinic acid) were associated with rapid decline. Further investigation into longitudinal SCD nephropathy (SCDN) trajectory, early markers of SCDN, and tools for risk stratification should inform interventional studies targeted to slowing GFR decline and improving SCD outcomes.