Effect of weight loss on the estimated glomerular filtration rates of obese patients at risk of chronic kidney disease: the RIGOR-TMU study

Complications and Mortality After Surgery in Patients with Chronic Kidney Disease: A Retrospective Cohort Study Based on a Multicenter Clinical Database

Objective

To evaluate the postoperative complications and mortality among patients with chronic kidney disease.

Methods

Biochemical measurements, diagnosis codes for CKD and comorbid conditions for surgical patients aged ≥20 years were obtained from electronic medical records of three large hospitals in Taiwan in 2009-2017. We conducted this retrospective cohort study by using propensity score-matching methods to balance the baseline characteristics between CKD and non-CKD groups. The multiple logistic regression analysis was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of risks of primary outcome (included postoperative mortality) and secondary outcome (included postoperative infectious complications and non-infectious complications) associated with CKD.

Results

Among 31950 eligible surgical patients, the adjusted OR of in-hospital mortality in patients with CKD was 5.49 (95% CI 3.42-8.81) compared with that in non-CKD controls. The adjusted ORs of postoperative septicemia, pneumonia and cellulitis in patients with CKD were 5.90 (95% CI 2.12-16.5), 5.39 (95% CI 1.37-21.16), and 4.42 (95% CI 1.57-12.4), respectively, when compared with the non-CKD patients. CKD was also associated with postoperative stroke (OR 2.21, 95% CI 1.47-3.31).

Conclusion

Patients with CKD are at increased risk of postoperative stroke, infectious complications, and mortality. Our study implicated that it is crucial to improve the levels of hemoglobin and K+ in patients with CKD before surgery. Preventive strategies should be developed to improve clinical outcomes in these populations.

Impact of chronic kidney disease and end-stage renal disease on the mid-term adverse outcomes in diabetic patients with cardiovascular diseases

The evidence for the impact of renal dysfunction in patients with diabetes mellitus (DM) and first cardiovascular diseases on mid-term adverse outcomes remain scarce. This study included the data of patients with DM having first atherosclerotic cardiovascular disease (ASCVD) or congestive heart failure (CHF) from the Taipei Medical University Clinical Research Database. A Cox proportional hazards regression model was used to assess the impact of chronic kidney disease (CKD) or end-stage renal disease (ESRD) on the 1-year mortality and recurrent ASCVD/CHF outcomes. We enrolled 21,320 patients with DM hospitalized for ASCVD or CHF; of them, 18,185, 2639, and 496 were assigned to the non-CKD, CKD, and ESRD groups, respectively. After propensity score matching, compared with the non-CKD group, the CKD and ESRD groups had higher mid-term all-cause mortality (adjusted hazard ratio 1.72 [95% confidence interval 1.48-1.99] and 2.77 [2.05-3.73], respectively), cardiovascular death (1.84 [1.44-2.35] and 1.87 [1.08-3.24], respectively), and recurrent hospitalization for ASCVD (1.44 [1.24-1.68] and 2.33 [1.69-3.23], respectively) and CHF (2.08 [1.75-2.47] and 1.50 [1.04-2.17], respectively). The advancing age was associated with mortality in CKD/ESRD groups. In CKD group, male sex was associated with all-cause mortality and recurrent ASCVD risk; the diuretics usage was associated with mortality and recurrent CHF risks. Our findings suggest that CKD and ESRD are significant risk factors for mid-term adverse outcomes in patients with DM and established cardiovascular diseases. Additionally, old age, male sex and diuretics usage requires attention. Further good quality studies are needed in the future.

The expected changes with different periods of home-based resistance exercise in patients with chronic kidney disease

BACKGROUND

The comprehensive impact of prolonged home-based resistance training on individuals grappling with chronic kidney disease (CKD) have yet to be fully elucidated. This study aimed to explore the outcomes of varying exercise durations on physical performance, nutritional status, and kidney function within this specific population, encompassing patients undergoing dialysis and those affected by severe sarcopenia.

METHODS

This was a 1-year observational double cohort study following a 52-week longitudinal design, we enrolled 101 adult CKD outpatients. These participants were divided into two groups: the continuous group, comprising individuals who consistently exercised for over 6 months, and the interrupted group, which included those who did not sustain regular exercise for the same duration. The exercise regimen involved resistance exercises conducted at least 3 to 5 days per week, involving activities like lifting dumbbells and executing weighted wall squats. Physical activity assessments and biochemical blood tests were conducted at weeks 0, 4, 16, 28, 40, and 52 for all participants.

RESULTS

The continuous exercise group exhibited better handgrip strength and sit-to-stand movement compared to the interrupted group. Their estimated glomerular filtration rate stayed steady while the interrupted group was declined. Additionally, those who exercised consistently had better metabolism: higher carbon dioxide levels, increased albumin, better nutritional scores, and lower levels of blood urea nitrogen, creatinine, fasting blood glucose, and body weight. Subsequent adjustments for potential confounding factors continued to show improved physical performance and kidney function over time.

CONCLUSION

Our findings indicate the advantageous impact of extended resistance exercise training on overall health of CKD patients, even those on dialysis or with severe sarcopenia. Dedication to this exercise routine could improve kidney function, metabolism, and physical abilities in these patients.

The impact of weight loss on renal function in individuals with obesity and type 2 diabetes: a comprehensive review

Obesity and Type 2 Diabetes (T2D) are two highly prevalent diseases that exhibit a complex interplay between them. Obesity serves as a primary risk factor for the development of T2D, and conversely, individuals with T2D often exhibit comorbid obesity. Renal dysfunction emerges as a critical consequence of the convergence of obesity and Type 2 Diabetes, contributing significantly to the overall burden of complications associated with these conditions. Recognizing the profound implications of renal dysfunction in individuals contending with both obesity and Type 2 Diabetes, interventions targeting weight loss have gained prominence as potential therapeutic avenues. Weight loss not only addresses the primary risk factor of obesity but also holds the promise of mitigating the progression of Type 2 Diabetes and its associated renal complications. This comprehensive review aims to explore the impact of weight loss on renal function in individuals contending with the convergence of obesity and T2D.

Relationship between metformin use and lactic acidosis in advanced chronic kidney disease: The REMIND-TMU study

BACKGROUND

Evidence of metformin-associated lactic acidosis (MALA) in advanced chronic kidney disease (CKD) has been limited due to high mortality rate but rare incidence rate. The mechanism of increased MALA in advanced CKD is mainly based on the hypothesis of decreased drug elimination, which might also be confounded by increased comorbidities as CKD progresses. The goal of the study is to analyze the incidence and associated factors of lactic acidosis between metformin user and non-user with advanced CKD.

METHODS

This study used a three million population-based, propensity score-matched cohort from 2008 to 2016. The primary outcome was laboratory-defined lactic acidosis. Relationships between the probability of lactic acidosis and various estimated glomerular filtration rate (eGFR) values in advanced CKD patients were also presented in regression analysis.

RESULTS

Adults with type 2 diabetes whose eGFR was <30 mL/min/1.73 m² were enrolled in this study. After the process of propensity score matching, 7707 patients were divided into metformin and non-metformin groups. In linear regression model, metformin significantly increased the risk of lactic acidosis (p=0.0204) as the eGFR declined in advanced CKD over a mean follow up of over 600 days even after confounder adjustment with age, sex and comorbidities.

CONCLUSIONS

Metformin was associated with a significant increased risk of laboratory-defined lactic acidosis (p=0.0204) even after adjusting confounder such as age, sex and underlying comorbidities. This "REMIND" study reminds us that metformin-associated lactic acidosis is mainly caused by decreased drug renal elimination other than underlying comorbidities in advanced CKD patients.

Identification of core genes and pathways between geriatric multimorbidity and renal insufficiency: potential therapeutic agents discovered using bioinformatics analysis

Background

Geriatric people are prone to suffer from multiple chronic diseases, which can directly or indirectly affect renal function. Through bioinformatics analysis, this study aimed to identify key genes and pathways associated with renal insufficiency in patients with geriatric multimorbidity and explore potential drugs against renal insufficiency.

Methods

The text mining tool Pubmed2Ensembl was used to detect genes associated with the keywords including "Geriatric", "Multimorbidity" and "Renal insufficiency". The GeneCodis program was used to specify Gene Ontology (GO) biological process terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Protein–protein interaction (PPI) networks were constructed using STRING and visualized in Cytoscape. Module analysis was performed using CytoHubba and Molecular Complex Detection (MCODE) plugins. GO and KEGG analysis of gene modules was performed using the Database for Annotation, Visualization and Integrated Discover (DAVID) platform database. Genes clustered in salient modules were selected as core genes. Then, the functions and pathways of core genes were visualized using ClueGO and CluePedia. Finally, the drug-gene interaction database was used to explore drug-gene interactions of the core genes to identify drug candidates for renal insufficiency in patients with geriatric multimorbidity.

Results

Through text mining, 351 genes associated with "Geriatric", "Multimorbidity" and "Renal insufficiency" were identified. A PPI network consisting of 216 nodes and 1087 edges was constructed and CytoHubba was used to sequence the genes. Five gene modules were obtained by MCODE analysis. The 26 genes clustered in module1 were selected as core candidate genes primarily associated with renal insufficiency in patients with geriatric multimorbidity. The HIF-1, PI3K-Akt, MAPK, Rap1, and FoxO signaling pathways were enriched. We found that 21 of the 26 selected genes could be targeted by 34 existing drugs.

Conclusion

This study indicated that CST3, SERPINA1, FN1, PF4, IGF1, KNG1, IL6, VEGFA, ALB, TIMP1, TGFB1, HGF, SERPINE1, APOA1, APOB, FGF23, EGF, APOE, VWF, TF, CP, GAS6, APP, IGFBP3, P4HB, and SPP1 were key genes potentially involved with renal insufficiency in patients with geriatric multimorbidity. In addition, 34 drugs were identified as potential agents for the treatment and management of renal insufficiency.

A systematic review of statistical methodology used to evaluate progression of chronic kidney disease using electronic healthcare records

Background

Electronic healthcare records (EHRs) are a useful resource to study chronic kidney disease (CKD) progression prior to starting dialysis, but pose methodological challenges as kidney function tests are not done on everybody, nor are tests evenly spaced. We sought to review previous research of CKD progression using renal function tests in EHRs, investigating methodology used and investigators’ recognition of data quality issues.

Methods and findings

We searched for studies investigating CKD progression using EHRs in 4 databases (Medline, Embase, Global Health and Web of Science) available as of August 2021. Of 80 articles eligible for review, 59 (74%) were published in the last 5.5 years, mostly using EHRs from the UK, USA and East Asian countries. 33 articles (41%) studied rates of change in eGFR, 23 (29%) studied changes in eGFR from baseline and 15 (19%) studied progression to binary eGFR thresholds. Sample completeness data was available in 44 studies (55%) with analysis populations including less than 75% of the target population in 26 studies (33%). Losses to follow-up went unreported in 62 studies (78%) and 11 studies (14%) defined their cohort based on complete data during follow up. Methods capable of handling data quality issues and other methodological challenges were used in a minority of studies.

Conclusions

Studies based on renal function tests in EHRs may have overstated reliability of findings in the presence of informative missingness. Future renal research requires more explicit statements of data completeness and consideration of i) selection bias and representativeness of sample to the intended target population, ii) ascertainment bias where follow-up depends on risk, and iii) the impact of competing mortality. We recommend that renal progression studies should use statistical methods that take into account variability in renal function, informative censoring and population heterogeneity as appropriate to the study question.

Development of a Risk Model for Predicting Microalbuminuria in the Chinese Population Using Machine Learning Algorithms

Objective

Microalbuminuria (MAU) occurs due to universal endothelial damage, which is strongly associated with kidney disease, stroke, myocardial infarction, and coronary artery disease. Screening patients at high risk for MAU may aid in the early identification of individuals with an increased risk of cardiovascular events and mortality. Hence, the present study aimed to establish a risk model for MAU by applying machine learning algorithms.

Methods

This cross-sectional study included 3,294 participants ranging in age from 16 to 93 years. R software was used to analyze missing values and to perform multiple imputation. The observed population was divided into a training set and a validation set according to a ratio of 7:3. The first risk model was constructed using the prepared data, following which variables with P <0.1 were extracted to build the second risk model. The second-stage model was then analyzed using a chi-square test, in which a P ≥ 0.05 was considered to indicate no difference in the fit of the models. Variables with P <0.05 in the second-stage model were considered important features related to the prevalence of MAU. A confusion matrix and calibration curve were used to evaluate the validity and reliability of the model. A series of risk prediction scores were established based on machine learning algorithms.

Results

Systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), triglyceride (TG) levels, sex, age, and smoking were identified as predictors of MAU prevalence. Verification using a chi-square test, confusion matrix, and calibration curve indicated that the risk of MAU could be predicted based on the risk score.

Conclusion

Based on the ability of our machine learning algorithm to establish an effective risk score, we propose that comprehensive assessments of SBP, DBP, FBG, TG, gender, age, and smoking should be included in the screening process for MAU.

Effects of osteoporosis medications on bone fracture in patients with chronic kidney disease

PURPOSE OF THE STUDY

The risk of bone fracture is high in patients with chronic kidney disease (CKD), and aggressive treatment to reduce fragility fracture risk is the major strategy. However, the outcomes of osteoporosis medications in patients with CKD remain unclear.

STUDY DESIGN

Patients with stage 3-5 CKD during 2011-2019 were enrolled. Patients were divided into two groups based on receiving osteoporosis medications (bisphosphonates, raloxifene, teriparatide or denosumab) or not. Two groups were matched at a 1:1 ratio by using propensity scores. The outcomes of interest were bone fractures, cardiovascular (CV) events and all-cause mortality. Cox proportional hazard regression models were applied to identify the risk factors. Additional stratified analyses by cumulative dose, treatment length and menopause condition were performed.

RESULTS AND CONCLUSIONS

67 650 patients were included. After propensity score matching, 1654 patients were included in the study and control group, respectively. The mean age was 70.2±12.4 years, and 32.0% of patients were men. After a mean follow-up of 3.9 years, the incidence rates of bone fracture, CV events and all-cause mortality were 2.0, 1.7 and 6.5 per 1000 person-months, respectively. Multivariate analysis results showed that osteoporosis medications reduced the risk of CV events (HR, 0.35; 95% CI, 0.18 to 0.71; p=0.004), but did not alleviate the risks of bone fracture (HR, 1.48; 95% CI, 0.73 to 2.98; p=0.28) and all-cause mortality (HR, 0.93; 95% CI, 0.67 to 1.28; p=0.65). Stratified analysis showed that bisphosphonates users have most benefits in the reduction of CV events (HR, 0.26; 95% CI, 0.11 to 0.64; p=0.003). In conclusion, osteoporosis medications did not reduce the risk of bone fractures, or mortality, but improved CV outcomes in patients with CKD.

Safety and efficacy of very low carbohydrate diet in patients with diabetic kidney disease-A randomized controlled trial

Introduction

There is limited data on the effects of low carbohydrate diets on renal outcomes particularly in patients with underlying diabetic kidney disease. Therefore, this study determined the safety and effects of very low carbohydrate (VLCBD) in addition to low protein diet (LPD) on renal outcomes, anthropometric, metabolic and inflammatory parameters in patients with T2DM and underlying mild to moderate kidney disease (DKD).

Materials and methods

This was an investigator-initiated, single-center, randomized, controlled, clinical trial in patients with T2DM and DKD, comparing 12-weeks of low carbohydrate diet (<20g daily intake) versus standard low protein (0.8g/kg/day) and low salt diet. Patients in the VLCBD group underwent 2-weekly monitoring including their 3-day food diaries. In addition, Dual-energy x-ray absorptiometry (DEXA) was performed to estimate body fat percentages.

Results

The study population (n = 30) had a median age of 57 years old and a BMI of 30.68kg/m2. Both groups showed similar total calorie intake, i.e. 739.33 (IQR288.48) vs 789.92 (IQR522.4) kcal, by the end of the study. The VLCBD group showed significantly lower daily carbohydrate intake 27 (IQR25) g vs 89.33 (IQR77.4) g, p<0.001, significantly higher protein intake per day 44.08 (IQR21.98) g vs 29.63 (IQR16.35) g, p<0.05 and no difference in in daily fat intake. Both groups showed no worsening of serum creatinine at study end, with consistent declines in HbA1c (1.3(1.1) vs 0.7(1.25) %) and fasting blood glucose (1.5(3.37) vs 1.3(5.7) mmol/L). The VLCBD group showed significant reductions in total daily insulin dose (39(22) vs 0 IU, p<0.001), increased LDL-C and HDL-C, decline in IL-6 levels; with contrasting results in the control group. This was associated with significant weight reduction (-4.0(3.9) vs 0.2(4.2) kg, p = <0.001) and improvements in body fat percentages. WC was significantly reduced in the VLCBD group, even after adjustments to age, HbA1c, weight and creatinine changes. Both dietary interventions were well received with no reported adverse events.

Conclusion

This study demonstrated that dietary intervention of very low carbohydrate diet in patients with underlying diabetic kidney disease was safe and associated with significant improvements in glycemic control, anthropometric measurements including weight, abdominal adiposity and IL-6. Renal outcomes remained unchanged. These findings would strengthen the importance of this dietary intervention as part of the management of patients with diabetic kidney disease.

Improvement of kidney function in patients with chronic kidney disease and severe obesity after bariatric surgery: A systematic review and meta-analysis

The general management for chronic kidney disease (CKD) includes treating reversible causes, including obesity, which may be both a driver and comorbidity for CKD. Bariatric surgery has been shown to reduce the likelihood of CKD progression and improve kidney function in observational studies. We performed a systematic review and meta-analysis of patients with at least stage 3 CKD and obesity receiving bariatric surgery. We searched Embase, MEDLINE, CENTRAL and identified eligible studies reporting on kidney function outcomes in included patients before and after bariatric surgery with comparison to a medical intervention control if available. Risk of bias was assessed with the Newcastle-Ottawa Risk of Bias score. Nineteen studies were included for synthesis. Bariatric surgery showed improved eGFR with a mean difference (MD) of 11.64 (95%CI: 5.84 to 17.45, I²  = 66%) ml/min/1.73m² and reduced SCr with MD of -0.24 (95%CI -0.21 to -0.39, I²  = 0%) mg/dl after bariatric surgery. There was no significant difference in the relative risk (RR) of having CKD stage 3 after bariatric surgery, with a RR of -1.13 (95%CI: -0.83 to -2.07, I²  = 13%), but there was reduced likelihood of having uACR >30 mg/g or above with a RR of -3.03 (95%CI: -1.44 to -6.40, I²  = 91%). Bariatric surgery may be associated with improved kidney function with the reduction of BMI and may be a safe treatment option for patients with CKD. Future studies with more robust reporting are required to determine the feasibility of bariatric surgery for the treatment of CKD.

Investigation of dual antiplatelet therapy after coronary stenting in patients with chronic kidney disease

Background

Dual antiplatelet therapy (DAPT) is currently the standard treatment for the prevention of ischemic events after stent implantation. However, the optimal DAPT duration remains elusive for patients with chronic kidney disease (CKD). Therefore, we aimed to compare the effectiveness and safety between long-term and short-term DAPT after coronary stenting in patients with CKD.

Methods

This retrospective cohort study analyze data from the Taipei Medical University (TMU) Institutional and Clinical Database, which include anonymized electronic health data of 3 million patients that visited TMU Hospital, Wan Fang Hospital, and Shuang Ho Hospital. We enrolled patients with CKD after coronary stenting between 2008 and 2019. The patients were divided into the long-term (>6 months) and short-term DAPT group (≤ 6 months). The primary end point was major adverse cardiovascular events (MACE) from 6 months after the index date. The secondary outcomes were all-cause mortality and Thrombolysis in Myocardial Infarction (TIMI) bleeding.

Results

A total of 1899 patients were enrolled; of them, 1112 and 787 were assigned to the long-term and short-term DAPT groups, respectively. Long-term DAPT was associated with similar risk of MACE (HR: 1.05, 95% CI: 0.65–1.70, P = 0.83) compare with short-term DAPT. Different CKD risk did not modify the risk of MACE. There was also no significant difference in all-cause mortality (HR: 1.10, 95% CI: 0.75–1.61, P = 0.63) and TIMI bleeding (HR 1.19, 95% CI: 0.86–1.63, P = 0.30) between groups.

Conclusions

Among patients with CKD and coronary stenting, we found that long-term and short-term DAPT tied on the risk of MACE, all-cause mortality and TIMI bleeding.

Alterations of bone markers in obese patients with type 2 diabetes after bariatric surgery: A meta-analysis and systemic review of randomized controlled trials and cohorts

BACKGROUND

The aim of this study is to evaluate the alterations in bone mineral density and other surrogate markers for osteoporosis in obese patients with type 2 diabetes mellitus (T2DM) who received Roux-en-Y gastric bypass (RYGB) versus medical treatment as control.

METHODS

We searched 4 electronic databases and reference lists of relevant studies for eligible research published before December, 2019. After quality assessment, eligible studies were synthesized for relevant outcomes, including lumbar spine bone mineral density (L-spine BMD) change, total hip BMD change, osteocalcin level, C-terminal telopeptide level, and parathyroid hormone level.

RESULTS

Three randomized clinical trials and 2 observational studies concerning 307 total obese T2DM patients were included. Follow-up ranged from 12 to 60 months. Patients underwent RYGB surgery were associated with both higher L-spine BMD loss (mean difference: -2.90, 95% CI: -2.99∼-2.81, P < .00001) and total hip BMD loss (mean difference: -5.81, 95% CI: -9.22∼-2.40, P = .0008). As to biochemical markers of bone metabolism, we found significantly higher osteocalcin level in medical treatment (control) group compared with RYGB group (mean difference: 11.16, 95% CI: 8.57-13.75, P < .00001). However, higher C-terminal telopeptide level and parathyroid hormone level were noted in medical treatment group (control) compared with RYGB group (mean difference: 0.29, 95% CI: 0.11-0.48, P = .002; mean difference: 1.56, 95% CI: 0.84-2.27, P < .0001).

CONCLUSIONS

RYGB surgery is associated with negative impact on bone metabolism and increase the risk of osteoporosis in obese patients with T2DM. We suggest that clinicians acknowledge the adverse effects of surgery and keep monitoring bone mineral components in post-RYGB populations. Further studies regarding the optimal amount of perioperative and postsurgical supplementation should be evaluated.

Potential Therapeutic Targets of Obesity-Related Glomerulopathy

The global increase of obesity parallels the obesity-related glomerulopathy (ORG) epidemic. The purpose of this review is to emphasize the potential therapeutic targets of ORG as well as the corresponding possible mechanisms. We systematically identified surveys, reports, and published studies that included data for the purpose of this review and did literature analysis. Under circumstance of obesity, weight loss, and renin-angiotensin-aldosterone blockade are the most studied therapies, effective to induce antiproteinuric effects and reversal of hyperfiltration in ORG. Glucagon-like peptide-1-based therapies led to improvement in proteinuria. Newer therapies directed to lipid metabolism, including farnesoid X receptor and takeda G protein-coupled receptor 5 agonists, peroxisome proliferator-activated receptor α agonists, hold therapeutic promise. Prevention and treatments of obesity and ORG are of great importance.

Weight loss, malnutrition, and cachexia in COVID-19: facts and numbers

Patients with COVID-19 disease are prone to develop significant weight loss and clinical cachexia. Three reports with altogether 589 patients that reported on weight loss and cachexia in COVID-19 were identified. Disease severity of patients and the timing of the assessment during the disease course in these patients were variable-65 patients (11%) were intensive care treated at the time of assessment, and 183 (31%) were cared for in sub-intensive or intermediate care structures. The frequency of weight loss ≥5% (that defines cachexia) was 37% (range 29-52%). Correlates of weight loss occurrence were reported to be raised C-reactive protein levels, impaired renal function status, and longer duration of COVID-19 disease. Underweight status by WHO criteria (BMI < 18.5 kg/m² ) was only observed in 4% of patients analysing data from seven studies with 6661 patients. Cachexia assessment in COVID-19 needs assessment of weight loss. COVID-19 associated cachexia is understood to affect muscle and fat tissue as is also seen in many other chronic illness-associated forms of cachexia. There are many factors that can contribute to body wasting in COVID-19, and they include loss of appetite and taste, fever and inflammation, immobilization, as well as general malnutrition, catabolic-anabolic imbalance, endocrine dysfunction, and organ-specific complications of COVID-19 disease such as cardiac and renal dysfunction. Treatment of COVID-19 patients should include a focus on nutritional support and rehabilitative exercise whenever possible. Specific anti-cachectic therapies for COVID-19 do not exist, but constitute a high medical need to prevent long-term disability due to acute COVID-19 disease.

Inflammation and Oxidative Stress in Chronic Kidney Disease-Potential Therapeutic Role of Minerals, Vitamins and Plant-Derived Metabolites

Chronic kidney disease (CKD) is a debilitating pathology with various causal factors, culminating in end stage renal disease (ESRD) requiring dialysis or kidney transplantation. The progression of CKD is closely associated with systemic inflammation and oxidative stress, which are responsible for the manifestation of numerous complications such as malnutrition, atherosclerosis, coronary artery calcification, heart failure, anemia and mineral and bone disorders, as well as enhanced cardiovascular mortality. In addition to conventional therapy with anti-inflammatory and antioxidative agents, growing evidence has indicated that certain minerals, vitamins and plant-derived metabolites exhibit beneficial effects in these disturbances. In the current work, we review the anti-inflammatory and antioxidant properties of various agents which could be of potential benefit in CKD/ESRD. However, the related studies were limited due to small sample sizes and short-term follow-up in many trials. Therefore, studies of several anti-inflammatory and antioxidant agents with long-term follow-ups are necessary.

Prevalence of Early Chronic Kidney Disease and Main Associated Factors in Spanish Population: Populational Study

The aim of this study was to determine the prevalence of early chronic kidney disease (EKD) (stages 1 and 2) and the factors associated. This was a populational study including individuals from 18–75 years randomly selected from 18 Primary Healthcare centers in the area of Barcelonès Nord and Maresme (Catalunya, Spain). Variables: anamnesis, physical examination, blood pressure, and analysis. EKD was defined with by a glomerular filtration rate (GFR) ≥60 mL/min/1.73 m² and albumin/creatinine ratio (ACR) ≥17 mg/g in men and ≥25 mg/g in women confirmed with two determinations. 2871 individuals: 43% men, mean age 55 years (19–75), 32.2% obese, 50.5% abdominal obesity, 21.1% hypertensive, and 10.6% diabetic. Prevalence of EKD: With one determination 157 individuals (5.5%), 110 men (9%) and 47 women (2.8%); with two determinations 109 individuals (3.8%), 85 men (7%), and 24 women (1.5%). Factors independently associated with the multivariate logistic regression model: Man (OR 3.35), blood pressure ≥ 135/85 mmHg (OR 2.29), BMI ≥ 30 kg/m² (OR 2.48), glycemia ≥ 100 mg/dL (OR 1.73), smoker (OR 1.67) and age (OR 1.04). The prevalence varies if the diagnosis is established based on one or two analytical determinations, overestimated if only one determination is made and depends on the value chosen to define urine albumin excretion.

Effect of weight loss on the estimated glomerular filtration rates of obese patients at risk of chronic kidney disease: the RIGOR-TMU study

BACKGROUND

Weight-reduction therapies, including bariatric surgery (BS), are standard treatments for severely obese patients with type 2 diabetes; however, the outcomes of these therapies are inconclusive for obese patients with chronic kidney disease (CKD). This study aimed to investigate the effects of BS or non-surgical interventions on the estimated glomerular filtration rate (eGFR) and to determine whether BS can be recommended for renal function preservation based on body mass index (BMI) and eGFR changes in obese patients with CKD.

METHODS

This study used data from the weight Reduction Intervention on GFR in Obese Patients with Renal Impairment-Taipei Medical University (TMU) study, which was a large, long-term, propensity score-matched cohort study based on clinical data from patients who registered at weight-reduction centres at TMU and its affiliated hospitals from 2008 to 2016. The patients were stratified according to whether they had undergone BS and into the mild, moderate, and high CKD risk groups using the Kidney Disease: Improving Global Outcomes guidelines. The primary outcome was the eGFR calculated using the Taiwan Chronic Kidney Disease-Epidemiology Collaboration equation. Cox regression models were used to determine hazard ratios (HRs) for eGFR decreases ≥25%.

RESULTS

A total of 4332 obese patients were enrolled in this study. After propensity score matching, 1620 patients, including 60.2% women, with a mean age of 36.5 (9.9) years were divided into BS or non-surgery groups (n = 810 per group). The overall mean eGFRs increased by 4.4 (14) mL/min·1.73 m² and decreased by 6.4 (16.0) mL/min·1.73 m² in the BS and non-surgery groups, respectively. The decrease in BMI in the BS and non-surgery groups were 2.5 and 1.3 kg/m² , respectively. In the moderate/high CKD risk BS group, a significant correlation was evident between an increased eGFR and a reduced BMI (Spearman's correlation -0.229, P < 0.001). The Cox regression analysis showed that the BS group had a significantly lower risk of an eGFR decline ≥25% at 12 months [adjusted HR (aHR) 0.47, P = 0.03). After BS, obese patients with hypertension or albuminuria had significantly lower risks of eGFR declines ≥25% (aHR 0.37, P = 0.02 and aHR 0.13, P = 0.0018, respectively).

CONCLUSIONS

Bariatric surgery was associated with eGFR preservation in all obese patients and, particularly, in those with moderate-to-high CKD risks. A longer term outcome study is warranted to determine the benefits of BS for CKD patients.