Kidney Function Measures and Mortality: A Mendelian Randomization Study.

RATIONALE & OBJECTIVE: Individuals with a low estimated glomerular filtration rate (eGFR) are at a high risk of death. However, the causes underpinning this association are largely uncertain. This study aimed to assess the causal relationship of low eGFR with all-cause and cause-specific mortality. STUDY DESIGN: Retrospective cohort study incorporating Mendelian randomization (MR). SETTING & PARTICIPANTS: Individual-level data from 436,214 White participants (54.3% female; aged 56.8±8.0 years) included in the UK Biobank. EXPOSURES: eGFR estimated using cystatin C (eGFRcyst). OUTCOMES: The outcomes of interest included all-cause mortality, cardiovascular mortality, cancer mortality, infection mortality, and other-cause mortality. ANALYTICAL APPROACH: Cox proportional hazards analysis for the conventional observational analyses; linear and nonlinear MR analyses implemented using genetic allele scores as instrumental variables representing kidney function to estimate the effect of kidney function on the survival outcomes. RESULTS: During a median follow-up of 12.1 years, there were 30,489 deaths, 6,098 of which were attributed to cardiovascular events, 15,538 to cancer, 1,516 to infection, and 7,227 to other events. In the conventional observational analysis, eGFRcyst exhibited a nonlinear association with all the outcomes. MR analysis suggested that a genetically predicted lower eGFRcyst was linearly associated with a higher rate of cardiovascular mortality (HR, 1.43; 95% CI, 1.18-1.75) across the entire measurement range (every 10-mL/min/1.73m2 decrement). Nonetheless, no causal associations between eGFRcyst and all-cause mortality (HR, 1.07; 95% CI, 0.98-1.17) or any types of noncardiovascular mortality were detected. LIMITATIONS: Potential misclassification of the actual cause of death, a nonrepresentative sample, and potential error in the interpretation of the magnitude of associations generated in MR analyses. CONCLUSIONS: These findings suggest a potential causal association between low eGFR and cardiovascular mortality in the general population, but no causal relationship with all-cause mortality or noncardiovascular mortality was observed. Further studies in other populations are warranted to confirm these findings. PLAIN-LANGUAGE SUMMARY: This study investigated the existence of a causal relationship between lower kidney function and death of different causes. Using data from 436,214 people in the United Kingdom, we applied conventional statistical analyses and those incorporating genetic data to implement Mendelian randomization, an approach that estimates causal associations. The observational analysis showed a nonlinear association between kidney function and various types of mortality outcomes. However, Mendelian randomization analysis suggested a linear increase in the risk of cardiovascular mortality with lower kidney function, but no causal link between the level of kidney function and all-cause or noncardiovascular mortality was identified. Managing kidney health may help reduce cardiovascular mortality, but caution is needed in interpreting the magnitudes of these results. Further validation in other populations and in those with advanced kidney failure is needed.

Incidence, risk factors and outcome of postoperative acute kidney injury in China.

BACKGROUND: Postoperative acute kidney injury (AKI) is a common condition after surgery, however, the available data about nationwide epidemiology of postoperative AKI in China from large and high-quality studies are limited. This study aimed to determine the incidence, risk factors and outcomes of postoperative AKI among patients undergoing surgery in China. METHODS: This was a large, multicentre, retrospective study performed in 16 tertiary medical centres in China. Adult patients (≥18 years of age) who underwent surgical procedures from 1 January 2013 to 31 December 2019 were included. Postoperative AKI was defined by the Kidney Disease: Improving Global Outcomes creatinine criteria. The associations of AKI and in-hospital outcomes were investigated using logistic regression models adjusted for potential confounders. RESULTS: Among 520 707 patients included in our study, 25 830 (5.0%) patients developed postoperative AKI. The incidence of postoperative AKI varied by surgery type, which was highest in cardiac (34.6%), urologic (8.7%) and general (4.2%) surgeries. A total of 89.2% of postoperative AKI cases were detected in the first 2 postoperative days. However, only 584 (2.3%) patients with postoperative AKI were diagnosed with AKI on discharge. Risk factors for postoperative AKI included older age, male sex, lower baseline kidney function, pre-surgery hospital stay ≤3 days or >7 days, hypertension, diabetes mellitus and use of proton pump inhibitors or diuretics. The risk of in-hospital death increased with the stage of AKI. In addition, patients with postoperative AKI had longer lengths of hospital stay (12 versus 19 days) and were more likely to require intensive care unit care (13.1% versus 45.0%) and renal replacement therapy (0.4% versus 7.7%). CONCLUSIONS: Postoperative AKI was common across surgery type in China, particularly for patients undergoing cardiac surgery. Implementation and evaluation of an alarm system is important for the battle against postoperative AKI.

Detecting Neonatal AKI by Serum Cystatin C.

SIGNIFICANCE STATEMENT: Serum creatinine is not a sensitive biomarker for neonatal AKI because it is confounded by maternal creatinine level, gestational age, and neonatal muscle mass. In this multicenter cohort study of 52,333 hospitalized Chinese neonates, the authors proposed serum cystatin C-related criteria (CyNA) for neonatal AKI. They found that cystatin C (Cys-C) is a robust and sensitive biomarker for identifying AKI in neonates who are at an elevated risk of in-hospital mortality and that CyNA detects 6.5 times as many cases as the modified Kidney Disease Improving Global Outcomes creatinine criteria. They also show that AKI can be detected using a single test of Cys-C. These findings suggest that CyNA shows promise as a powerful and easily applicable tool for detecting AKI in neonates. BACKGROUND: Serum creatinine is not a sensitive biomarker for AKI in neonates. A better biomarker-based criterion for neonatal AKI is needed. METHODS: In this large multicenter cohort study, we estimated the upper normal limit (UNL) and reference change value (RCV) of serum cystatin C (Cys-C) in neonates and proposed cystatin C-based criteria (CyNA) for detecting neonatal AKI using these values as the cutoffs. We assessed the association of CyNA-detected AKI with the risk of in-hospital death and compared CyNA performance versus performance of modified Kidney Disease Improving Global Outcomes (KDIGO) creatinine criteria. RESULTS: In this study of 52,333 hospitalized neonates in China, Cys-C level did not vary with gestational age and birth weight and remained relatively stable during the neonatal period. CyNA criteria define AKI by a serum Cys-C of ≥2.2 mg/L (UNL) or an increase in Cys-C of ≥25% (RCV) during the neonatal period. Among 45,839 neonates with measurements of both Cys-C and creatinine, 4513 (9.8%) had AKI detected by CyNA only, 373 (0.8%) by KDIGO only, and 381 (0.8%) by both criteria. Compared with neonates without AKI by both criteria, neonates with AKI detected by CyNA alone had an increased risk of in-hospital mortality (hazard ratio [HR], 2.86; 95% confidence interval [95% CI], 2.02 to 4.04). Neonates with AKI detected by both criteria had an even higher risk of in-hospital mortality (HR, 4.86; 95% CI, 2.84 to 8.29). CONCLUSIONS: Serum Cys-C is a robust and sensitive biomarker for detecting neonatal AKI. Compared with modified KDIGO creatinine criteria, CyNA is 6.5 times more sensitive in identifying neonates at elevated risk of in-hospital mortality.

Statin initiation and risk of incident kidney disease in patients with diabetes.

BACKGROUND: The role of statin therapy in the development of kidney disease in patients with type 2 diabetes mellitus (DM) remains uncertain. We aimed to determine the relationships between statin initiation and kidney outcomes in patients with type 2 DM. METHODS: Through a new-user design, we conducted a multicentre retrospective cohort study using the China Renal Data System database (which includes inpatient and outpatient data from 19 urban academic centres across China). We included patients with type 2 DM who were aged 40 years or older and admitted to hospital between Jan. 1, 2000, and May 26, 2021, and excluded those with pre-existing chronic kidney disease and those who were already on statins or without follow-up at an affiliated outpatient clinic within 90 days after discharge. The primary exposure was initiation of a statin. The primary outcome was the development of diabetic kidney disease (DKD), defined as a composite of the occurrence of kidney dysfunction (estimated glomerular filtration rate [eGFR] < 60 mL/min/1.73 m2 and > 25% decline from baseline) and proteinuria (a urinary albumin-to-creatinine ratio ≥ 30 mg/g and > 50% increase from baseline), sustained for at least 90 days; secondary outcomes included development of kidney function decline (a sustained > 40% decline in eGFR). We used Cox proportional hazards regression to evaluate the relationships between statin initiation and kidney outcomes, as well as to conduct subgroup analyses according to patient characteristics, presence or absence of dyslipidemia, and pattern of dyslipidemia. For statin initiators, we explored the association between different levels of lipid control and outcomes. We conducted analyses using propensity overlap weighting to balance the participant characteristics. RESULTS: Among 7272 statin initiators and 12 586 noninitiators in the weighted cohort, statin initiation was associated with lower risks of incident DKD (hazard ratio [HR] 0.72, 95% confidence interval [CI] 0.62-0.83) and kidney function decline (HR 0.60, 95% CI 0.44-0.81). We obtained similar results to the primary analyses for participants with differing patterns of dyslipidemia, those prescribed different statins, and after stratification according to participant characteristics. Among statin initiators, those with intensive control of high-density lipoprotein cholesterol (LDL-C) (< 1.8 mmol/L) had a lower risk of incident DKD (HR 0.51, 95% CI 0.32-0.81) than those with inadequate lipid control (LDL-C ≥ 3.4 mmol/L). INTERPRETATION: For patients with type 2 DM admitted to and followed up in academic centres, statin initiation was associated with a lower risk of kidney disease development, particularly in those with intensive control of LDL-C. These findings suggest that statin initiation may be an effective and reasonable approach for preventing kidney disease in patients with type 2 DM.

Healthy Lifestyle and Mortality Among Adults Receiving Hemodialysis: The DIET-HD Study.

RATIONALE & OBJECTIVE: A healthy lifestyle promotes cardiovascular health and reduces cardiac-related mortality in the general population, but its benefits for people receiving maintenance hemodialysis are uncertain. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 5,483 of 9,757 consecutive adults receiving maintenance hemodialysis (January 2014 to June 2017, median dialysis vintage: 3.6 years) in a multinational private dialysis network and with complete lifestyle data. EXPOSURE: Based on the American Heart Association's recommendations for cardiovascular prevention, a modified healthy lifestyle score was the sum of 4 components addressing use of smoking tobacco, physical activity, diet, and control of systolic blood pressure. OUTCOME: Cardiovascular and all-cause mortality. ANALYTICAL APPROACH: Adjusted proportional hazards regression analyses with country as a random effect to estimate the associations between lifestyle score (low [0-2 points] as the referent, medium [3-5], and high [6-8]) and mortality. Associations were expressed as adjusted hazard ratio (AHR) with 95% CI. RESULTS: During a median of 3.8 years (17,451 person-years in total), there were 2,163 deaths, of which 826 were related to cardiovascular disease. Compared with patients who had a low lifestyle score, the AHRs for all-cause mortality among those with medium and high lifestyle scores were 0.75 (95% CI, 0.65-0.85) and 0.64 (95% CI, 0.54-0.76), respectively. Compared with patients who had a low lifestyle score, the AHRs for cardiovascular mortality among those with medium and high lifestyle scores were 0.73 (95% CI, 0.59-0.91) and 0.65 (95% CI, 0.49-0.85), respectively. LIMITATIONS: Self-reported lifestyle, data-driven approach. CONCLUSIONS: A healthier lifestyle is associated with lower all-cause and cardiovascular mortality among patients receiving maintenance hemodialysis.

Modifiable Lifestyle Factors for Primary Prevention of CKD: A Systematic Review and Meta-Analysis.

BACKGROUND: Despite increasing incidence of CKD, no evidence-based lifestyle recommendations for CKD primary prevention apparently exist. METHODS: To evaluate the consistency of evidence associating modifiable lifestyle factors and CKD incidence, we searched MEDLINE, Embase, CINAHL, and references from eligible studies from database inception through June 2019. We included cohort studies of adults without CKD at baseline that reported lifestyle exposures (diet, physical activity, alcohol consumption, and tobacco smoking). The primary outcome was incident CKD (eGFR<60 ml/min per 1.73 m2). Secondary outcomes included other CKD surrogate measures (RRT, GFR decline, and albuminuria). RESULTS: We identified 104 studies of 2,755,719 participants with generally a low risk of bias. Higher dietary potassium intake associated with significantly decreased odds of CKD (odds ratio [OR], 0.78; 95% confidence interval [95% CI], 0.65 to 0.94), as did higher vegetable intake (OR, 0.79; 95% CI, 0.70 to 0.90); higher salt intake associated with significantly increased odds of CKD (OR, 1.21; 95% CI, 1.06 to 1.38). Being physically active versus sedentary associated with lower odds of CKD (OR, 0.82; 95% CI, 0.69 to 0.98). Current and former smokers had significantly increased odds of CKD compared with never smokers (OR, 1.18; 95% CI, 1.10 to 1.27). Compared with no consumption, moderate consumption of alcohol associated with reduced risk of CKD (relative risk, 0.86; 95% CI, 0.79 to 0.93). These associations were consistent, but evidence was predominantly of low to very low certainty. Results for secondary outcomes were consistent with the primary finding. CONCLUSIONS: These findings identify modifiable lifestyle factors that consistently predict the incidence of CKD in the community and may inform both public health recommendations and clinical practice.

Lifestyle interventions for preventing and ameliorating CKD in primary and secondary care.

PURPOSE OF REVIEW: Despite the growth in chronic kidney disease (CKD) epidemics, evidence-based lifestyle recommendations for primary prevention of CKD are limited by reliance on observational studies and predominantly pilot clinical trials. RECENT FINDINGS: Emerging data have shown lifestyle modification strategies for primary CKD prevention with the most evidence favoring a healthy dietary pattern (rich in fruit, vegetables, potassium and have a higher plant-based to animal protein ratio), and diet low in sodium, being physically active, avoiding tobacco smoking, moderating alcohol consumption and maintaining a healthy body weight. The way these behavioral interventions can be implemented in practice should consider their synergistic benefit as well as mechanisms to facilitate long-term behavior change. Sustaining long-term behavior change remains a challenge in practice, particularly due to a lack of healthcare resources and behavior relapse. Some suggestions to mitigate this include ensuring adequate time is spent in intervention codesign and planning, utilizing adaptive trial/intervention designs with regular intervention tailoring for intervention dose, intensity, duration, and modality. SUMMARY: A number of modifiable lifestyle behaviors consistently associate with developing CKD in the community. The current evidence base, despite its inherent limitations, may inform both public health recommendations and clinical practice.

Short- and long-term outcomes after incident pneumonia in adults with chronic kidney disease: a time-dependent analysis from the Stockholm CREAtinine Measurement project.

BACKGROUND: Little is known about the health sequelae of pneumonia in persons with chronic kidney disease (CKD). METHODS: We studied adults with CKD in Stockholm during 2006-11, who not previously been diagnosed with lower respiratory tract infections. We used multivariable-adjusted Cox regression with pneumonia as a time-varying exposure to estimate hazard ratios (HRs) [95% confidence intervals (CIs)] for the events of death, major adverse cardiovascular events (MACEs), acute kidney injury (AKI), CKD progression or hospitalization for urinary tract infections (UTIs)/sepsis. Cataract and knee/joint replacement served as negative control outcomes. RESULTS: We identified 71 931 adults (mean age 79 years, 59% women), of whom 8379 (12%) were diagnosed with pneumonia during follow-up; incident pneumonia was associated with 10 times higher adjusted mortality risk during the first 90 days [HR = 10.0, 95% confidence interval (CI) 9.5-10.5] and double the mortality beyond 90 days from pneumonia diagnosis (HR = 2.0; 95% CI 1.9-2.1). Incident pneumonia was similarly associated with higher adjusted risk of MACE (<90 days: HR = 12.6; 95% CI 12.0-13.3; ≥90 days: HR = 1.5; 95% CI 1.4-1.6). The adjusted risk of CKD progression and UTI/sepsis hospitalization was highest within 90 days from pneumonia but remained elevated thereafter. For AKI, the association with incident pneumonia was only seen within 90 days. Neither cataract nor knee/joint replacement was related to pneumonia. CONCLUSIONS: Incident pneumonia was associated with increased risks of MACE, CKD progression, severe UTI/sepsis and death, with risks highest soon after pneumonia diagnosis but extending beyond 90 days. Our findings highlight the susceptibility for adverse outcomes of CKD patients following pneumonia diagnosis, and may inform clinical decisions regarding vaccination strategies.

Effects of dialysis modality choice on the survival of end-stage renal disease patients in southern China: a retrospective cohort study.

BACKGROUND: The optimal choice of treatment, with hemodialysis (HD) or peritoneal dialysis (PD), for end-stage renal disease (ESRD) patients, is still controversial. Only a few studies comparing HD and PD have been conducted in China, which has the largest number of dialysis patients in the world. METHODS: A retrospective cohort study was conducted on ESRD patients who began renal replacement treatment from January 1, 2012 to December 31, 2017 in Guangdong Provincial Hospital of Chinese Medicine. Propensity scoring match was applied to balance the baseline conditions and multivariate Cox regression analysis to compare the mortality between HD and PD patients, and evaluated the correlation between mortality and various baseline characteristics. RESULTS: A total of 436 HD patients and 501 PD patients were included in this study, and PD patients had better survival than HD patients, but the difference was not statistically significant. For younger ESRD patients (≤60-year-old), the overall survival of PD was better than that of HD, but HD was associated with a lower risk of death in older patients (> 70-year-old). This difference was still significant after adjustment for a variety of confounding factors. Female gender, age at dialysis initiation, cardiovascular disease, cholesterol, and HD were risk factors of all-cause mortality in the younger subgroup, while PD was risk factor in the older subgroup. CONCLUSION: PD may be a better choice for younger ESRD patients, and HD for the older patients.

Vitamin D deficiency and treatment versus risk of infection in end-stage renal disease patients under dialysis: a systematic review and meta-analysis.

Background: Infections are common and can be fatal in patients undergoing long-term dialysis. Recent studies have shown conflicting evidence associating infection with vitamin D status or use of vitamin D and have not been systematically reviewed in this population. Methods: We searched PubMed, Web of Science, Cochrane Library, Embase and three Chinese databases from inception until December 2017 for interventional [non-randomized or randomized controlled trials (RCTs)], cohort and case-control studies on levels of serum 25-hydroxyvitamin D [25(OH)D] or use of vitamin D [supplemental nutritional vitamin D or vitamin D receptor activator (VDRA)] and infection (any infection, infection-required hospitalization or infection-related death or composite) in long-term dialysis patients. We conducted a meta-analysis on the relative risk (RR) of infection and level of 25(OH)D or use of vitamin D. Results: Of 2440 reports identified, 17 studies met inclusion criteria, all with moderate quality, with 6 cohort studies evaluating 25(OH)D serum concentrations (n = 5714) and 11 (2 RCTs and 9 observational studies) evaluating the use of vitamin D (n = 92 309). The risk of composite infection was 39% lower {relative risk [RR] 0.61 [95% confidence interval (CI) 0.41-0.89]} in the subjects with high or normal levels of 25(OH)D than in those with low levels. When compared with those who did not use vitamin D, the pooled adjusted risk for composite infection was 41% lower in those who used vitamin D [RR 0.59 (95% CI 0.43-0.81)]. Conclusions: High or normal serum levels of 25(OH)D and the use of vitamin D, particularly VDRA, were each associated with a lower risk of composite infection in long-term dialysis patients.

Oral Astragalus (Huang qi) for preventing frequent episodes of acute respiratory tract infection in children.

BACKGROUND: Acute respiratory tract infections (ARTIs) are common in children and can involve both upper and lower airways. Many children experience frequent ARTI episodes or recurrent respiratory tract infections (RRTIs) in early life, which creates challenges for paediatricians, primary care physicians, parents and carers of children.In China, Astragalus (Huang qi), alone or in combination with other herbs, is used by Traditional Chinese Medicine (TCM) practitioners in the form of a water extract, to reduce the risk of ARTIs; it is believed to stimulate the immune system. Better understanding of the therapeutic mechanisms of Astragalus may provide insights into ARTI prevention, and consequently reduced antibiotic use. OBJECTIVES: To assess the effectiveness and safety of oral Astragalus for preventing frequent episodes of acute respiratory tract infections (ARTIs) in children in community settings. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 12, 2015), MEDLINE (Ovid) (1946 to 31 December 2015), Embase (Elsevier) (1974 to 31 December 2015), AMED (Ovid) (1985 to 31 December 2015), Chinese National Knowledge Infrastructure (CNKI) (1979 to 31 December 2015) and Chinese Scientific Journals full text database (CQVIP) (1989 to 31 December 2015), China Biology Medicine disc (CBM 1976 to 31 December 2015) and Wanfang Data Knowledge Service Platform (WanFang) (1998 to 31 December 2015). SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing oral Astragalus as a sole Chinese herbal preparation with placebo to prevent frequent episodes of ARTIs in children. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures for this review. We assessed search results to identify relevant studies. We planned to extract data using standardised forms. Disagreements were to be resolved through discussion. Risk of bias was to be assessed using the Cochrane 'Risk of bias' tool. We planned to use mean difference (MD) or standardised mean difference (SMD) for continuous data and risk ratio (RR) or odds ratio (OR) to analyse dichotomous data, both with 95% confidence intervals (CIs). MAIN RESULTS: We identified 6080 records: 3352 from English language databases, 2724 from Chinese databases, and four from other sources. Following initial screening and deduplication, we obtained 120 full-text papers for assessment. Of these, 21 were not RCTs; 55 did not meet the inclusion criteria because: participants were aged over 14 years; definition was not included for recurrent or frequent episodes;Astragalus preparation was not an intervention; Astragalus preparation was in the formula but was not the sole agent; the Astragalus preparation was not administered orally; or Astragalus was used for treatment rather than prevention of ARTI. A further 44 studies were excluded because they were not placebo-controlled, although other inclusion criteria were fulfilled.No RCTs met our inclusion criteria. AUTHORS' CONCLUSIONS: We found insufficient evidence to enable assessment of the effectiveness and safety of oral Astragalus as a sole intervention to prevent frequent ARTIs in children aged up to 14 years.

Dietary interventions for mineral and bone disorder in people with chronic kidney disease.

BACKGROUND: Chronic kidney disease-mineral and bone disorder (CKD-MBD) is a systemic dysfunction of mineral and bone metabolism in people with CKD. Recent research shows that phosphate retention plays a significant role in the development of CKD-MBD. Compared with drug therapies, dietary interventions may be simple, inexpensive and feasible for phosphate retention. However, there is little evidence to support these interventions. OBJECTIVES: Our objective was to assess the benefits and harms of any dietary intervention for preventing and treating CKD-MBD. SEARCH METHODS: We searched Cochrane Kidney and Transplant's Specialised Register to 27 August 2015 through contact with the Trials' Search Co-ordinator using search terms relevant to this review. We also searched the Chinese Biomedicine Database (CBM) (1976 to August 2015), China Knowledge Resource Integrated Database (CNKI) (1979 to August 2015), and VIP (1989 to August 2015). SELECTION CRITERIA: Randomised controlled trials (RCTs) and quasi-RCTs looking at dietary interventions for prevention or treatment of CKD-MBD were eligible for inclusion. DATA COLLECTION AND ANALYSIS: Two authors independently assessed the eligibility, methodological quality, and extracted data. Continuous outcomes (serum calcium level, serum phosphorus level, calcium × phosphate product, parathyroid hormone (PTH), fibroblast growth factor 23 (FGF-23) and alkaline phosphatase) were expressed as mean difference (MD) with 95% confidence interval (CI). Dichotomous outcomes (mortality) were expressed as risk ratio (RR) with 95% CI. We used a random-effects model to meta-analyse studies. MAIN RESULTS: Nine studies were included in this review which analysed 634 participants. Study duration ranged from 4 to 24 weeks. The interventions included calcium-enriched bread, low phosphorus intake, low protein intake, very low protein intake, post haemodialysis supplements and hypolipaemic diet. Only one study reported death; none of the included studies reported cardiovascular events or fractures. There was insufficient reporting of design and methodological aspects among the included studies to enable robust assessment of risk of bias.There was limited and low-quality evidence to indicate that calcium-enriched bread increased serum calcium (1 study, 53 participants: MD -0.16 mmol/L, 95% CI -0.51 to -0.31), decreased serum phosphorus (53 participants: MD -0.41 mmol/L, 95% CI -0.51 to -0.31) and decreased the calcium × phosphate product (53 participants: MD -0.62 mmol²/L², 95% CI -0.77 to -0.47).Very low protein intake was not superior to conventional low protein intake in terms of effect on serum phosphorus (2 studies, 41 participants: MD -0.12 mmol/L, 95% CI -0.50 to 0.25), serum calcium (MD 0.00 mmol/L, 95% CI -0.17 to 0.17), or alkaline phosphatase (MD -22.00 U/L, 95% CI -78.25 to 34.25). PTH was significantly lower in the very low protein intake group (2 studies, 41 participants: MD -69.64 pmol/L, 95% CI -139.83 to 0.54).One study reported no significant difference in the number of deaths between low phosphorus intake and normal diet (279 participants: RR 0.18, 95% CI 0.01 to 3.82). Low phosphorus intake decreased serum phosphorus (2 studies, 359 participants: MD -0.18 mmol/L, 95% CI -0.29 to -0.07; I(2) = 0%).One study reported post-haemodialysis supplements did not increase serum phosphorus compared to normal diet (40 participants: MD 0.12 mmol/L, 95% CI -0.24 to 0.49).One study reported low phosphorus intake plus lanthanum carbonate significantly decreased FGF-23 (19 participants: MD -333.80 RU/mL, 95% CI -526.60 to -141.00), but did not decrease serum phosphorus (19 participants: MD -0.10 mg/dL, 95% CI -0.38 to 0.58) or PTH (19 participants: MD 31.60 pg/mL, 95% CI -29.82 to 93.02). AUTHORS' CONCLUSIONS: There was limited low quality evidence to indicate that dietary interventions (calcium-enriched bread or low phosphorus/protein intake) may positively affect CKD-MBD by increasing serum calcium, decreasing serum phosphorus, the calcium × phosphate product and FGF-23. Large and well-designed RCTs are needed to evaluate the effects of various interventions for people with CKD-MBD.

Rationale and design of the Helping Ease Renal failure with Bupi Yishen compared with the Angiotensin II Antagonist Losartan (HERBAAL) trial: a randomized controlled trial in non-diabetes stage 4 chronic kidney disease.

BACKGROUND: Chronic kidney disease (CKD) is a global public health problem. Currently, as for advanced CKD populations, medication options limited in angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB), which were partially effective. A Chinese herbal compound, Bupi Yishen formula, has showed renal protective potential in experiments and retrospective studies. This study will evaluate the efficacy and safety of Bupi Yishen formula (BYF) in patients with CKD stage 4. DESIGN: In this double blind, double dummy, randomized controlled trial (RCT), there will be 554 non-diabetes stage 4 CKD patients from 16 hospitals included and randomized into two groups: Chinese medicine (CM) group or losartan group. All patients will receive basic conventional therapy. Patients in CM group will be treated with BYF daily while patients in control group will receive losartan 100 mg daily for one year. The primary outcome is the change in estimated glomerular filtration rate (eGFR) over 12 months. Secondary outcomes include the incidence of endpoint events, liver and kidney function, urinary protein creatinine ratio, cardiovascular function and quality of life. DISCUSSION: This study will be the first multi-center, double blind RCT to assess whether BYF, compared with losartan, will have beneficial effects on eGFR for non-diabetes stage 4 CKD patients. The results will help to provide evidence-based recommendations for clinicians. TRIAL REGISTRATION: Chinese Clinical Trial Registry Number: ChiCTR-TRC-10001518 .

Prevalence and associated factors of frailty in patients with chronic kidney disease: a cross-sectional analysis of PEAKING study.

AIM:  Frailty is common and is reported to be associated with adverse outcomes in patients with chronic diseases in Western countries. However, the prevalence of frailty remains unclear in individuals with chronic kidney disease (CKD) in China. We examined the prevalence of frailty and factors associated with frailty in patients with CKD. METHODS:  This was a cross-sectional analysis of 177 adult patients (mean age 54 ± 15 years, 52% men) with CKD from the open cohort entitled Physical Evaluation and Adverse outcomes for patients with chronic Kidney disease IN Guangdong (PEAKING). Frailty at baseline were assessed by FRAIL scale which included five items: fatigue, resistance, ambulation, illnesses, and loss of weight. Potential risk factors of frailty including age, sex, body mass index, and daily step counts recorded by ActiGraph GT3X + accelerometer were analyzed by multivariate logistic regression analysis. RESULTS: The prevalence of prefrailty and frailty was 50.0% and 11.9% in patients with stages 4-5 CKD, 29.6% and 9.3% in stage 3, and 32.1% and 0 in stages 1-2. In the multivariate logistic regression analysis, an increase of 100 steps per day (OR = 0.95, 95% CI 0.91-0.99, P = 0.01) and an increase of 5 units eGFR (OR = 0.82, 95% CI 0.68-0.99, P = 0.045) were inversely associated with being frail; higher BMI was associated with a higher likelihood of being frail (OR = 1.52, 95% CI 1.11-2.06, P = 0.008) and prefrail (OR = 1.25, 95% CI 1.10-1.42, P = 0.001). CONCLUSION:  Frailty and prefrailty were common in patients with advanced CKD. A lower number of steps per day, lower eGFR, and a higher BMI were associated with frailty in this population.

Interaction of general obesity and abdominal obesity with frailty in patients with chronic kidney disease: a nationally representative analysis.

Background: General and abdominal obesity are prevalent, with established associations to frailty in the elderly. However, few studies have investigated these associations in patients with chronic kidney disease (CKD), yielding inconsistent results. Methods: This cross-sectional study analysed data from the National Health and Nutrition Examination Survey (NHANES 2003-2018). Frailty was evaluated by the 36-item frailty index. General obesity was defined as a body mass index (BMI) >30 kg/m2; abdominal obesity was identified if waist circumference (WC) reached 102 cm in men and 88 cm in women. The associations of general and abdominal obesity with frailty were analysed using weighted multivariate logistic regression and restricted cubic splines. The interaction of general and abdominal obesity with frailty was examined. Results: A total of 5604 adult patients (median age 71 years, 42% men) with CKD were included in this analysis, with a median estimated glomerular filtration rate of 57.3 ml/min/1.73 m2. A total of 21% were frail with general obesity and 32% were frail with abdominal obesity. Neither general nor abdominal obesity alone was associated with frailty. There was an interaction between general and abdominal obesity with frailty. Compared with individuals with normal BMI and WC, those with both general and abdominal obesity, rather than either alone, exhibited significantly increased odds of frailty {odds ratio [OR] 1.53 [95% confidence interval (CI) 1.20-1.95]}. General obesity was associated with being frail only when CKD patients had abdominal obesity [OR 1.59 (95% CI 1.08-2.36)]. Conclusions: There may be an interaction between general and abdominal obesity with frailty in patients with CKD. Interventions aimed at preventing frailty should consider both aspects.

Real-world effectiveness of early insulin therapy on the incidence of cardiovascular events in newly diagnosed type 2 diabetes.

Early insulin therapy is capable to achieve glycemic control and restore ß-cell function in newly diagnosed type 2 diabetes (T2D), but its effect on cardiovascular outcomes in these patients remains unclear. In this nationwide real-world study, we analyzed electronic health record data from 19 medical centers across China between 1 January 2000, and 26 May 2022. We included 5424 eligible patients (mean age 56 years, 2176 women/3248 men) who were diagnosed T2D within six months and did not have prior cardiovascular disease. Multivariable Cox regression models were used to estimate the associations of early insulin therapy (defined as the first-line therapy for at least two weeks in newly diagnosed T2D patients) with the incidence of major cardiovascular events including coronary heart disease (CHD), stroke, and hospitalization for heart failure (HF). During 17,158 persons years of observation, we documented 834 incident CHD cases, 719 stroke cases, and 230 hospitalized cases for HF. Newly diagnosed T2D patients who received early insulin therapy, compared with those who did not receive such treatment, had 31% lower risk of incident stroke, and 28% lower risk of hospitalization for HF. No significant difference in the risk of CHD was observed. We found similar results when repeating the aforesaid analysis in a propensity-score matched population of 4578 patients and with inverse probability of treatment weighting models. These findings suggest that early insulin therapy in newly diagnosed T2D may have cardiovascular benefits by reducing the risk of incident stroke and hospitalization for HF.

Dipeptidyl peptidase 4 inhibitors vs. metformin for new-onset dementia: a propensity score-matched cohort study.

BACKGROUND: Hypoglycemic pharmacotherapy interventions for alleviating the risk of dementia remains controversial, particularly about dipeptidyl peptidase 4 (DPP4) inhibitors versus metformin. Our objective was to investigate whether the initiation of DPP4 inhibitors, as opposed to metformin, was linked to a reduced risk of dementia. METHODS: We included individuals with type 2 diabetes over 40 years old who were new users of DPP4 inhibitors or metformin in the Chinese Renal Disease Data System (CRDS) database between 2009 and 2020. The study employed Kaplan-Meier and Cox regression for survival analysis and the Fine and Gray model for the competing risk of death. RESULTS: Following a 1:1 propensity score matching, the analysis included 3626 DPP4 inhibitor new users and an equal number of metformin new users. After adjusting for potential confounders, the utilization of DPP4 inhibitors was associated with a decreased risk of all-cause dementia compared to metformin (hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.45-0.89). Subgroup analysis revealed that the utilization of DPP4 inhibitors was associated with a reduced incidence of dementia in individuals who initiated drug therapy at the age of 60 years or older (HR 0.69, 95% CI 0.48-0.98), those without baseline macrovascular complications (HR 0.62, 95% CI 0.41-0.96), and those without baseline microvascular complications (HR 0.67, 95% CI 0.47-0.98). CONCLUSION: In this real-world study, we found that DPP4 inhibitors presented an association with a lower risk of dementia in individuals with type 2 diabetes than metformin, particularly in older people and those without diabetes-related comorbidities.

Piperacillin/tazobactam and risk of acute kidney injury in adults hospitalized with infection without vancomycin: a multi-centre real-world data analysis.

BACKGROUND: There is uncertainty about whether piperacillin/tazobactam (PT) increases the risk of acute kidney injury (AKI) in patients without concomitant use of vancomycin. This study compared the risk of hospital-acquired AKI (HA-AKI) among adults treated with PT or antipseudomonal ß-lactams (meropenem, ceftazidime) without concomitant use of vancomycin. METHODS: This real-world study analysed the data from China Renal Data System and assessed the risk of HA-AKI in adults hospitalized with infection after exposure to PT, meropenem or ceftazidime in the absence of concomitant vancomycin. The primary outcome was any stage of HA-AKI according to the Kidney Disease Improving Global Outcomes guidelines. A multi-variable Cox regression model and different propensity score (PS) matching models were used. RESULTS: Among the 29,441 adults [mean (standard deviation) age 62.44 (16.84) years; 17,980 females (61.1%)] included in this study, 14,721 (50%) used PT, 9081 (31%) used meropenem and 5639 (19%) used ceftazidime. During a median follow-up period of 8 days, 2601 (8.8%) develped HA-AKI. The use of PT was not associated with significantly higher risk of HA-AKI compared with meropenem [adjusted hazard ratio (aHR) 1.07, 95% confidence interval (CI) 0.97-1.19], ceftazidime (aHR 1.09, 95% CI 0.92-1.30) or both agents (aHR 1.07, 95% CI 0.97-1.17) after adjusting for confounders. Results were consistent in stratified analyses, PS matching using logistic regression or random forest methods to generate a PS, and in an analysis restricting outcomes to AKI stage 2-3. CONCLUSIONS: Without concomitant use of vancomycin, the risk of AKI following PT therapy is comparable with that of meropenem or ceftazidime among adults hospitalized with infection.

Immunosuppression versus Supportive Care on Kidney Outcomes in IgA Nephropathy in the Real-World Setting.

BACKGROUND: The efficacy of immunosuppression in the management of immunoglobulin A (IgA) nephropathy remains highly controversial. The study was conducted to assess the effect of immunosuppression, compared with supportive care, in the real-world setting of IgA nephropathy. METHODS: A cohort of 3946 patients with IgA nephropathy, including 1973 new users of immunosuppressive agents and 1973 propensity score-matched recipients of supportive care, in a nationwide register data from January 2019 to May 2022 in China was analyzed. The primary outcome was a composite of 40% eGFR decrease of the baseline, kidney failure, and all-cause mortality. A Cox proportional hazard model was used to estimate the effects of immunosuppression on the composite outcomes and its components in the propensity score-matched cohort. RESULTS: Among 3946 individuals (mean [SD] age 36 [10] years, mean [SD] eGFR 85 [28] ml/min per 1.73 m 2 , and mean [SD] proteinuria 1.4 [1.7] g/24 hours), 396 primary composite outcome events were observed, of which 156 (8%) were in the immunosuppression group and 240 (12%) in the supportive care group. Compared with supportive care, immunosuppression treatment was associated with 40% lower risk of the primary outcome events (adjusted hazard ratio, 0.60; 95% confidence interval, 0.48 to 0.75). Comparable effect size was observed for glucocorticoid monotherapy and mycophenolate mofetil alone. In the prespecified subgroup analysis, the treatment effects of immunosuppression were consistent across ages, sexes, levels of proteinuria, and values of eGFR at baseline. Serious adverse events were more frequent in the immunosuppression group compared with the supportive care group. CONCLUSIONS: Immunosuppressive therapy, compared with supportive care, was associated with a 40% lower risk of clinically important kidney outcomes in patients with IgA nephropathy.

Predicting in-hospital outcomes of patients with acute kidney injury.

Acute kidney injury (AKI) is prevalent and a leading cause of in-hospital death worldwide. Early prediction of AKI-related clinical events and timely intervention for high-risk patients could improve outcomes. We develop a deep learning model based on a nationwide multicenter cooperative network across China that includes 7,084,339 hospitalized patients, to dynamically predict the risk of in-hospital death (primary outcome) and dialysis (secondary outcome) for patients who developed AKI during hospitalization. A total of 137,084 eligible patients with AKI constitute the analysis set. In the derivation cohort, the area under the receiver operator curve (AUROC) for 24-h, 48-h, 72-h, and 7-day death are 95·05%, 94·23%, 93·53%, and 93·09%, respectively. For dialysis outcome, the AUROC of each time span are 88·32%, 83·31%, 83·20%, and 77·99%, respectively. The predictive performance is consistent in both internal and external validation cohorts. The model can predict important outcomes of patients with AKI, which could be helpful for the early management of AKI.