Objective: Exploring the effect and mechanism of Xinyang Tablet on reduction of ferroptosis in myocardial cells from mice with chronic heart failure. Methods: Sixty C57BL/6J mice were randomly assigned to the sham, model, Xinyang Tablet low-dose (0.34 g/kg), Xinyang Tablet medium-dose (0.68 g/kg), Xinyang Tablet high-dose (1.36 g/kg), and perindopril (0.607 mg/kg) groups using a random number table method (10 mice in each group). Except for the sham group, all other groups underwent aortic arch constriction surgery to construct a chronic heart failure model. On the third day after completion of the modeling, each treatment group was administered the corresponding medication by gavage, while the sham and model groups were administered equal volumes of water by gavage once a day for eight consecutive weeks. After treatment, cardiac ultrasound was used to detect the structure and function of the mouse heart. Hematoxylin and eosin staining was used to detect pathological changes in mouse heart tissue. Masson staining was used to detect the proportion of fibrotic area of mouse heart tissue. Realtime fluorescence PCR was used to detect the mRNA expression of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), collagen 3α (Col3α), and myosin heavy chain 7 (MYH7) in mouse myocardial tissue. Transmission electron microscope was used to detect the ultrastructure of myocardial cell mitochondria. Reactive oxygen species (ROS) staining was used to detect the mean fluorescence intensity of ROS in myocardial tissue. Micro-determination was used to detect superoxide dismutase (SOD) activity in myocardial tissue. An immunofluorescence assay was used to detect the mean fluorescence intensity of phosphorylated histone deacetylase 2 (p-HDAC2) in myocardial cell. Western blotting was used to detect the protein expression of nuclear factor-erythroid 2-related factor 2 (Nrf2), p-HDAC2, nicotinamide adenine dinucleotide phosphate oxidase 1 (NOX1), glutathione peroxidase 4 (GPX4), and cystine glutamate reverse transporter (xCT) in mouse myocardial tissue. Results: Compared to the sham group, the model group showed a decrease in left ventricular ejection fraction (LVEF), left ventricular fraction shortening (LVFS), an increase in left ventricular end-systolic diameter(LVESD) and left ventricular end-diastolic diameter (LVEDD), an increase in the proportion of cardiac fibrosis area, an increase in relative expression levels of ANP, BNP, Col3α, and MYH7 mRNA, an increase in ROS mean fluorescence intensity, a decrease in SOD activity, an increase in mean fluorescence intensity of p-HDAC2, an increase in relative expression levels of p-HDAC2 and NOX1 proteins, and a decrease in relative expression levels of Nrf2, GPX4, and xCT proteins (P<0.05). Myocardial fibrosis lesions are obvious, with disordered mitochondrial arrangement, decreased volume and shrinkage, increased membrane density, and reduced mitochondrial cristae. Compared to the model group, the LVEF and LVFS of mice in each dose group of Xinyang Tablet and the perindopril group increased, LVESD and LVEDD decreased, the proportion of fibrotic area of heart tissue decreased, the relative expression levels of ANP, BNP, Col3α, MYH7 mRNA decreased, ROS mean fluorescence intensity decreased, SOD activity increased, mean fluorescence intensity of p-HDAC2 decreased, relative expression levels of p-HDAC2 and NOX1 proteins decreased, and relative expression levels of Nrf2 and xCT proteins increased (P<0.05). Myocardial fibrosis was reduced, the mitochondrial arrangement was more regular, the mitochondria enlarged, the membrane density was reduced, and mitochondrial cristae increased. Compared to the model group, the relative expression level of the GPX4 protein in myocardial tissue increased in the Xinyang Tablet medium-, high-dose, and the perindopril groups (P<0.05). Conclusion Xinyang Tablet can improve ferroptosis and ventricular remodeling in mice with chronic heart failure by regulating the HDAC2-mediated Nrf2 antioxidant pathway.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Objective To explore the relationship between geriatric nutritional risk index(GNRI)and adverse outcomes in elderly patients undergoing maintenance hemodialysis(MHD).Methods A prospective cohort trial was conducted on 337 MHD patients aged ≥60 years in hemodialysis centers of 11 hospitals in Beijing from April to June 2017.Their baseline data were collected,and they were divided into non-malnutrition(GNRI≥98,226 cases),mild malnutrition(92≤GNRI＜98,81 cases),and major malnutrition groups(GNRI＜92,30 cases).All of them were followed up until June 2018.The endpoint events were all-cause mortality and cardiovascular disease(CVD)mortality.Kaplan-Meier survival analysis was used to compare the cumulative survival rate among the 3 groups.Multivariate Cox regression model was employed to analyze the relationship of GNRI with all-cause and CVD mortality.Results The mild and major malnutrition groups had significantly lower BMI,serum albumin level and GNRI(P＜0.01).During the median follow-up of 52(4.4-52.0)weeks,56(16.6％)patients died of all-cause death and 25(44.6％)of CVD death.Kaplan-Meier survival curve showed significant differences in all-cause mortality(x2=30.484,P＜0.01)and CVD mortality(x2=22.398,P＜0.01)in the 3 groups.Multivariate Cox regression analysis indicated that,as a continuous variable,elevated GNRI was a protective factor for all-cause mortality(HR=0.910,95％CI:0.870-0.952,P=0.000)and CVD mortality(HR=0.895,95％CI:0.852-0.940,P=0.000),and as a categorical variable,mild and major malnutri-tion were independently correlated with all-cause and CVD mortality(P＜0.05).Conclusion GNRI is an independent risk factor for all-cause and CVD mortality in elderly MHD patients.Mo-nitoring the nutritional status using GNRI can predict the risk of adverse prognosis.

Objective:To investigate the concern about pollen broadcasting in Chinese population from multiple dimensions and to understand the information about allergic rhinitis (AR) in China by analyzing related factors.Methods:From March 1 to September 30, 2022, a large-scale multi-center cross-sectional survey was conducted based on the Questionnaire Star platform in 21 Chinese hospitals. A total of 7 056 subjects from 7 regions in China: Northeast, North, East, Central, South, Southwest, and Northwest China were included. Basic characteristics (including social demographic characteristics and disease characteristics of AR patients), concern about pollen broadcasting, the willingness of pollen-induced AR (PiAR) patients to receive pollen broadcasting, and the treatment satisfaction rate of AR patients were collected. The chi-square test, multivariate linear regression model, and Logistic regression analysis were used to analyze the concern about pollen broadcasting in the Chinese population and related factors from multiple dimensions.Results:Among 7 056 subjects, 23.02% were concerned about pollen broadcasting. Among 3 176 self-reported AR and 1 019 PiAR patients, 25.60% and 39.16% were concerned about pollen broadcasting, respectively, which was higher than that of non-AR or non-PiAR subjects ( χ2 value was 21.74 and 175.11, respectively, both P<0.001). Among AR patients, the proportion of spring and autumn allergen-positive patients concerned about pollen broadcasting was higher than that in perennial allergen-positive patients ( χ2 value was 20.90 and 19.51, respectively, both P<0.001). The proportion of AR patients with asthma, sinusitis, allergic conjunctivitis, and cardiovascular and cerebrovascular diseases was higher than those without complications ( χ2 value was 50.83, 21.97, 56.78, 7.62, respectively, all P<0.05). The proportion of AR patients in North China who could find pollen broadcasting locally was 31.01%, significantly higher than those in other regions (all P<0.05). Multivariate linear regression model analysis showed that among PiAR patients, those with higher per capita household income and higher AR disease cognition levels had been concerned about pollen broadcasting in the past, and those complicated with allergic conjunctivitis had stronger intention to receive pollen broadcasting (B value was 0.24, 0.13, 0.66, 0.47, respectively, all P<0.05). The higher the disease cognition level of PiAR patients, the stronger their willingness to actively participate in treatment ( R2=0.72, P<0.001). Only 18.89% of AR patients felt satisfied with the treatment effect. Logistic regression analysis showed that in AR patients, the treatment satisfaction rate was significantly higher among those concerned about pollen broadcasting compared to those who were not ( OR=1.83, P<0.001). Conclusions:Currently, the dissemination of pollen broadcasting in China is hindered by various factors such as disease cognition level. The treatment satisfaction among AR patients remains unsatisfactory.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Objective:To explore the effect of pentraxin 3 (PTX3) on memory improvement and Aβ expression in Alzheimer's disease (AD) model mice.Methods:(1) Ten 5-month-old 5×FAD mice were randomly divided into PTX3 group and model group ( n=5); 5 C57BL/6 wild-type mice at the same age were selected as control group; mice in the PTX3 group and control group were stereotactically injected 4 μL 0.5 g/L PTX3 or same dose of phosphate buffered saline (PBS); Morris water maze test was used to detect the learning and memory abilities, Y maze test was used to detect the short-term memory, and ELISA was used to obsevre the contents of Aβ 40 and Aβ 42 in the brain hemisphere. (2) Twenty-five 3-month-old 5×FAD mice were randomly divided into model group, 2 μg/kg PTX3 group, 4 μg/kg PTX3 group, 8 μg/kg PTX3 group, and 16 μg/kg PTX3 group ( n=5); 5 C57BL/6 wild-type mice at the same age were selected as control group; mice in the PTX3 groups were intranasally injected 2, 4, 8, and 16 μg/kg PTX3, respectively; those in the model group and control group were intranasally injected same dose of PBS; injection was given once every 96 h for a total of 7 times. Morris water maze test was used to detect the learning and memory abilities, Y maze test was used to detect the short-term memory, and ELISA was used to obsevre the contents of Aβ 40 and Aβ 42 in the hippocampus. Results:(1) Compared with the model group, the PTX3 group had significantly shorter platform latency, higher percentage of exploration time and higher percentage of spontaneous alternations ( P<0.05). Compared with those in model group ([63.38±21.42] pg/mL, [29.77±6.11] pg/mL), the concentrations of Aβ 40 and Aβ 42 in the brain tissues of PTX3 group ([15.87±2.11] pg/mL, [16.55±1.95] pg/mL) were statistically lower ( P<0.05). (2) Compared with the model group, the 16 μg/kg PTX3 group had significantly shorter escape latency and higher percentage of exploration time ( P<0.05); compared with the model group, the 2 μg/kg PTX3 group and 16 μg/kg PTX3 group had significantly higher percentage of spontaneous alternations ( P<0.05). The contents of Aβ 40 and Aβ 42 in the hippocampus of 8 μg/kg PTX3 group and 16 μg/kg PTX3 group were statistically lower compared with those in the model group ( P<0.05). Conclusion:PTX3 may attenuate cognitive deficits and decrease Aβ expression in the brain or hippocampus tissues of 5×FAD mice with AD.

Objective:To analyze the clinical characteristics and risk factors of acute kidney injury (AKI) in portal venous hypertension patients undergoing transjugular intrahepatic portosystemic shunt (TIPS).Methods:It was a retrospective observational study. In this study, the clinical data of portal venous hypertension patients undergoing TIPS at Beijing Shijitan Hospital, Capital Medical University from October 16, 2020 to March 30, 2022 were collected retrospectively. According to the Kidney Disease: Improving Global Outcomes (KDIGO) definition of AKI, patients were divided into AKI group and non-AKI group. The clinical characteristics of the patients were compared between the two groups, and multivariate logistic regression was used to analyze the risk factors of AKI.Results:A total of 384 patients undergoing TIPS were included in this study, whose age was (53.17±13.35) years. Among them, 122 (31.8%) were female, and 32 patients (8.3%) had AKI. Compared to the non-AKI group, the proportion of patients with diabetes mellitus, baseline estimated glomerular filtration rate (eGFR) <60 ml·min -1·(1.73 m 2) -1 and intraoperative hypotension, Child-Pugh score of liver function, preoperative serum creatinine, preoperative blood uric acid, and postoperative portal venous pressure gradient (PPG) were higher in AKI group (all P<0.05), while the levels of hemoglobin and serum albumin were lower (both P<0.05). Multivariate logistic regression results showed that combined diabetes ( OR=3.728, 95% CI 1.262-11.013, P=0.017), baseline eGFR<60 ml·min -1·(1.73 m 2) -1( OR=3.571, 95% CI 1.356-9.400, P=0.010), decreased serum albumin ( OR=0.847, 95% CI 0.738-0.972, P=0.018), increased PPG after TIPS ( OR=1.096, 95% CI 1.002-1.200, P=0.045) and intraoperative hypotension ( OR=7.006, 95% CI 2.023-24.195, P=0.002) were independently associated with postoperative AKI in portal venous hypertension patients undergoing TIPS. Until discharge, 6 patients with AKI (18.8%) had complete renal function recovery, 24 patients (75.0%) partially recovered, and 2 patients (6.3%) did not recover. The length of hospital stay, hospitalization costs, and all-cause mortality in AKI patients were significantly higher than those in the non-AKI group ( P<0.05, respectively). Conclusions:AKI is not uncommon in patients receiving TIPS. The classical risk factors of AKI, such as diabetes and baseline renal dysfunction, and the factors affecting volumes like lower serum albumin level, hypotension during the operation, and higher PPG level are closely related to the incidence of AKI in these patients. AKI significantly increases the all-cause mortality and medical expenses, which is worth early prevention and treatment by clinicians.

Objective:To investigate the changes and associated factors of cerebral blood flow in middle-aged and elderly patients undergoing maintenance hemodialysis (MHD).Methods:This was a prospective observational study. End-stage renal disease (ESRD) patients undergoing MHD aged over 50 years at Beijing Shijitan Hospital, Capital Medical University from January 2023 to June 2023 were included. General clinical data of the selected individuals were collected, and dialysis related indicators were recorded and calculated. Mean flow velocity (MFV) of the middle cerebral arterial was measured by transcranial Doppler sonography (TCD) to represent cerebral blood flow throughout dialysis. Hemodialysis-related variables were collected. The MFV values of bilateral middle cerebral artery were measured through temporal windows at 7 time points: 15 minutes before dialysis (T1), 15 minutes (T2), 30 minutes (T3), 60 minutes (T4), 120 minutes (T5), 180 minutes (T6) during dialysis, and the endpoint of dialysis (T7), and the average values were recorded. The ΔMFV was calculated as pre-minus endpoint values of MFV. The Spearman rank correlation method was used to analyze the correlations between ΔMFV and dialysis-related variables, and multiple linear regression method was used to analyze the related factors of the changes in MFV.Results:This study included a total of 123 patients undergoing MHD, aged (63.63±8.44) years (range 50-85 years), including 99 males (80.5%). TCD examination demonstrated a decline trend in MFV throughout dialysis. The MFV at T7 was significantly lower than that at T1 ( Z=-7.650, P<0.001). The Spearman correlation analysis showed that the decline in MFV was correlated with ultrafiltration volume ( r=0.356), ultrafiltration rate ( r=0.371), the difference in systolic pressure (pre-analysis minus post-dialysis, r=0.251), the difference in mean arterial pressure (pre-dialysis minus post-dialysis, r=0.194), combined diabetes ( r=0.293), dialysis vintage ( r=0.220), Kt/V ( r=0.287), and serum albumin ( r=-0.295). Multiple linear regression analysis showed that combined with diabetes ( B=3.889, 95% CI 1.373-6.405, P=0.003), decreased serum albumin ( B=-0.456, 95% CI -0.877--0.036, P=0.034), increased ultrafiltration rate ( B=11.099, 95% CI 6.402-15.797, P<0.001) and the decline in systolic pressure ( B=0.062, 95% CI 0.008-0.116, P=0.026) were significantly associated with the decline in MFV throughout dialysis. Conclusions:In middle and elderly patients with ESRD undergoing hemodialysis, there is a decline trend in cerebral blood flow during hemodialysis. The combination of diabetes, lower serum albumin, higher ultrafiltration rate, and intradialytic systolic pressure decline are the risk factors influencing the intradialytic decline of cerebral blood flow.

Objective:To explore the relationship between geriatric nutritional risk index (GNRI) and modified creatinine index (mCI) and all-cause mortality in maintenance hemodialysis (MHD) patients.Methods:It was a prospective cohort study. The MHD patients aged≥50 years old at hemodialysis centers of eleven hospitals in Beijing from April to June 2017 were selected as subjects. Baseline clinical data of the patients were collected. The patients were divided into high GNRI group (≥98) and low GNRI group (<98), and high mCI group (≥20.16 mg·kg -1·d -1) and low mCI group (<20.16 mg·kg -1·d -1), and further divided into 4 groups: G1 group (high GNRI and high mCI), G2 group (high GNRI and low mCI), G3 group (low GNRI and high mCI) and G4 group (low GNRI and low mCI). The differences of clinical characteristics among the four groups were compared. The patients were followed-up until June 2018 or death or loss, and the endpoint event was all-cause mortality. Kaplan-Meier survival analysis was used to compare the differences of the cumulative survival rates among the four groups. A multivariate Cox regression model was used to analyze the relationship between GNRI and mCI and all-cause mortality. Results:A total of 613 patients were included in the study, aged (63.65±7.78) years old (ranged from 50 to 81 years old), with 355 males (57.91%). The GNRI and mCI were (99.35±5.75) and (20.16±2.79) mg·kg -1·d -1, respectively. There were 232 patients (37.85%) in the G1 group, 177 patients (28.87%) in the G2 group, 95 patients (15.50%) in the G3 group, and 109 patients (17.78%) in the G4 group. There were statistically significant differences in age, sex, proportion of diabetes, proportion of coronary heart disease, body mass index, serum albumin and serum creatinine among the four groups (all P<0.05). A total of 69 patients (11.26%) died during a median follow-up time of 52(4, 52) weeks. Kaplan-Meier survival curve results showed that the mortality of patients with low GNRI was higher than that of patients with high GNRI (log-rank χ 2=26.956, P<0.001), and the mortality of patients with low mCI was higher than that of patients with high mCI (log-rank χ 2=25.842, P<0.001). The mortality was 3.45% in group G1, 10.73% in group G2, 9.47% in group G3, and 30.28% in group G4, and the differences among the four groups were statistically significant (log-rank χ 2=57.153, P<0.001). Multivariate Cox regression analysis results showed that as continuous variables, GNRI ( HR=0.911, 95% CI 0.882-0.941, P<0.001) and mCI ( HR=0.873, 95% CI 0.797-0.956, P=0.003) were correlated with all-cause death. As categorical variables, compared with high GNRI group and high mCI group, patients with low GNRI ( HR=3.469, 95% CI 2.125-5.665, P<0.001) and low mCI ( HR=3.255, 95% CI 1.879-5.640, P<0.001) had higher risks of death. Compared with G1 group, patients in G2 group ( HR=2.488, 95% CI 1.079-5.738, P=0.033) and G4 group ( HR=9.449, 95% CI 4.362-20.470, P<0.001) had higher risks of death. Conclusions:GNRI and mCI are independent predictive factors of all-cause mortality in MHD patients. The combination of GNRI and MCI can more accurately predict the risk of all-cause death in middle-aged and elderly MHD patients.

Objective:To investigate the association between body mass index (BMI) and waist circumference (WC) with all-cause mortality in middle-aged and elderly patients receiving maintenance hemodialysis (MHD).Methods:It was a prospective cohort study. The clinical data of MHD patients aged ≥50 years old from eleven hemodialysis centers from April to June 2017 in Beijing were analyzed. The patients were divided into low BMI group [body mass index (BMI)<18.5 kg/m 2], normal BMI group (18.5 kg/m 2≤BMI <24.0 kg/m 2), overweight group (24.0 kg/m 2≤BMI<28.0 kg/m 2) and obesity group (BMI≥28.0 kg/m 2) by BMI, and central obesity group (male ≥85 cm, female ≥80 cm) and normal WC group (male <85 cm, female <80 cm) by WC. Kaplan-Meier survival analysis method was used to compare the difference of all-cause mortality between those groups. Multivariate Cox regression model was used to analyze the association of BMI and WC with all-cause mortality. Results:A total of 613 MHD patients were enrolled, with age of (63.82±7.14) years old and 258 (42.09%) females. There were 46 (7.50%) patients in the low BMI group, 303 (49.43%) patients in the normal BMI group, 227 (37.03%) patients in the overweight group and 37 (6.04%) patients in the obesity group. In addition, 346 (56.44%) patients were categorized as central obesity. Kaplan-Meier survival analysis results showed that the all-cause mortality rates of low BMI group (log-rank χ2=13.571, P<0.001) and obesity group (log-rank χ2=6.664 P=0.010) were higher than that of normal BMI group, and the all-cause mortality rate of central obesity group was higher than that of normal WC group (log-rank χ2=5.698, P=0.017). Multivariate Cox regression analysis results showed that，besides the low BMI group and obesity group (with normal BMI group as a reference, HR=5.289, 95% CI 2.318-12.067, P<0.001; HR=5.360, 95% CI 2.088-13.760, P<0.001, respectively), normal BMI and overweight combined with central obesity were also independently correlated with all-cause mortality (with normal WC group as a reference, HR=2.605, 95% CI 1.199-5.663, P=0.016; HR=1.787, 95% CI 1.026-3.732, P=0.031, respectively). Conclusions:Lower and higher BMI or combined central obesity are independently associated with all-cause mortality in the middle-aged and elderly patients receiving MHD.