Associations between heat waves and chronic kidney disease in China: The modifying role of land cover.

The increasing frequency of heat waves under the global urbanization and climate change background poses elevating risks of chronic kidney disease (CKD). Nevertheless, there has been no evidence on associations between long-term exposures to heat waves and CKD as well as the modifying effects of land cover patterns. Based on a national representative population-based survey on CKD covering 47,086 adults and high spatial resolution datasets on temperature and land cover data, we found that annual days of exposure to heat waves were associated with increased odds of CKD prevalence. For one day/year increases in HW_975_4d (above 97.5 % of annual maximum temperature and lasting for at least 4 consecutive days), the odds ratio (OR) of CKD was 1.14 (95 %CI: 1.12, 1.15). Meanwhile, stronger associations were observed in regions with lower urbanicity [rural: 1.14 (95 %CI: 1.12, 1.16) vs urban: 1.07 (95 %CI: 1.03, 1.11), Pinteraction < 0.001], lower water body coverage [lower: 1.14 (95 %CI: 1.12, 1.16) vs higher: 1.02 (95 %CI: 0.98, 1.05), Pinteraction < 0.001], and lower impervious area coverage [lower: 1.16 (95 %CI: 1.14, 1.18) vs higher: 1.06 (95 %CI: 1.03, 1.10), Pinteraction = 0.008]. In addition, this study found disparities in modifying effects of water bodies and impervious areas in rural and urban settings. In rural regions, the associations between heat waves and CKD prevalence showed a consistent decreasing trend with increases in both proportions of water bodies and impervious areas (Pinteraction < 0.05). Nevertheless, in urban regions, we observed significant effect modification by water bodies, but not by impervious areas. Our study indicates the need for targeted land planning as part of adapting to the kidney impacts of heat waves, with a focus on urbanization in rural regions, as well as water body construction and utilization in both rural and urban regions.

The Difference Between Cystatin C- and Creatinine-Based Estimated Glomerular Filtration Rate and Risk of Diabetic Microvascular Complications Among Adults With Diabetes: A Population-Based Cohort Study.

OBJECTIVE: The impact of the difference between cystatin C- and creatinine-based estimated glomerular filtration rate (eGFRdiff) on diabetic microvascular complications (DMCs) remains unknown. We investigated the associations of eGFRdiff with overall DMCs and subtypes, including diabetic retinopathy (DR), diabetic kidney disease (DKD), and diabetic neuropathy (DN). RESEARCH DESIGN AND METHODS: This prospective cohort study included 25,825 participants with diabetes free of DMCs at baseline (2006 to 2010) from the UK Biobank. eGFRdiff was calculated using both absolute difference (eGFRabdiff) and the ratio (eGFRrediff) between cystatin C- and creatinine-based calculations. Incidence of DMCs was ascertained using electronic health records. Cox proportional hazards regression models were used to evaluate the associations of eGFRdiff with overall DMCs and subtypes. RESULTS: During a median follow-up of 13.6 years, DMCs developed in 5,753 participants, including 2,752 cases of DR, 3,203 of DKD, and 1,149 of DN. Each SD decrease of eGFRabdiff was associated with a 28% higher risk of overall DMCs, 14% higher risk of DR, 56% higher risk of DKD, and 29% higher risk of DN. For each 10% decrease in eGFRrediff, the corresponding hazard ratios (95% CIs) were 1.16 (1.14, 1.18) for overall DMCs, 1.08 (1.05, 1.11) for DR, 1.29 (1.26, 1.33) for DKD, and 1.17 (1.12, 1.22) for DN. The magnitude of associations was not materially altered in any of the sensitivity analyses. CONCLUSIONS: Large eGFRdiff was independently associated with risk of DMCs and its subtypes. Our findings suggested monitoring eGFRdiff in the diabetes population has potential benefit for identification of high-risk patients.

Executive summary of the KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease: known knowns and known unknowns.

The Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease (CKD) updates the KDIGO 2012 guideline and has been developed with patient partners, clinicians, and researchers around the world, using robust methodology. This update, based on a substantially broader base of evidence than has previously been available, reflects an exciting time in nephrology. New therapies and strategies have been tested in large and diverse populations that help to inform care; however, this guideline is not intended for people receiving dialysis nor those who have a kidney transplant. The document is sensitive to international considerations, CKD across the lifespan, and discusses special considerations in implementation. The scope includes chapters dedicated to the evaluation and risk assessment of people with CKD, management to delay CKD progression and its complications, medication management and drug stewardship in CKD, and optimal models of CKD care. Treatment approaches and actionable guideline recommendations are based on systematic reviews of relevant studies and appraisal of the quality of the evidence and the strength of recommendations which followed the "Grading of Recommendations Assessment, Development, and Evaluation" (GRADE) approach. The limitations of the evidence are discussed. The guideline also provides practice points, which serve to direct clinical care or activities for which a systematic review was not conducted, and it includes useful infographics and describes an important research agenda for the future. It targets a broad audience of people with CKD and their healthcare, while being mindful of implications for policy and payment.

Surgical procedure and recurrence of upper urinary tract stone: a national-wide study based on hospitalized patients.

PURPOSE: This study aimed to investigate the influence of surgical intervention on recurrence risk of upper urinary tract stone and compare the medical burden of various surgical procedures. METHODS: This study analyzed data from patients with upper urinary tract stone extracted from a national database of hospitalized patients in China, from January 2013 to December 2018. Surgical recurrence was defined as patients experience surgical procedures for upper urinary tract stone again with a time interval over 90 days. Associations of surgical procedures with surgical recurrence were evaluated by Cox regression. RESULTS: In total, 556,217 patients with upper urinary tract stone were included in the present analysis. The mean age of the population was 49.9 ± 13.1 years and 64.1% were men. During a median follow-up of 2.7 years (IQR 1.5-4.0 years), 23,012 patients (4.1%) had surgical recurrence with an incidence rate of 14.9 per 1000 person-years. Compared to patients receiving open surgery, ESWL (HR, 1.59; 95% CI 1.49-1.70), URS (HR, 1.38; 95% CI 1.31-1.45), and PCNL (HR, 1.11; 95% CI 1.06-1.18) showed a greater risk for surgical recurrence. Patients receiving ESWL had the shortest hospital stay length and the lowest cost among the 4 procedures. CONCLUSIONS: Compared with open surgery, ESWL, URS, and PCNL are associated with higher risks of surgical recurrence for upper urinary tract stone, while ESWL showed the least medical burden including both expenditure and hospital stay length. How to keep balance of intervention efficacy and medical expenditure is an important issue to be weighed cautiously in clinic practice and studied more in the future.

Association between ambient PM1 and the prevalence of chronic kidney disease in China: A nationwide study.

Particulate of diameter ≤ 1 µm (PM1) presents a novel risk factor of adverse health effects. Nevertheless, the association of PM1 with the risk of chronic kidney disease (CKD) in the general population is not well understood, particularly in regions with high PM1 levels like China. Based on a nationwide representative survey involving 47,204 adults and multi-source ambient air pollution inversion data, the present study evaluated the association of PM1 with CKD prevalence in China. The two-year average PM1, particulate of diameter ≤ 2.5 µm (PM2.5), and PM1-2.5 values were accessed using a satellite-based random forest approach. CKD was defined as estimated glomerular filtration rate < 60 ml/min/1.73 m2 or albuminuria. The results suggested that a 10 µg/m3 rise in PM1 was related to a higher CKD risk (odds ratio [OR], 1.13; 95% confidence interval [CI] 1.08-1.18) and albuminuria (OR, 1.11; 95% CI, 1.05-1.17). The association between PM1 and CKD was more evident among urban populations, older adults, and those without comorbidities such as diabetes or hypertension. Every 1% increase in the PM1/PM2.5 ratio was related to the prevalence of CKD (OR, 1.03; 95% CI, 1.03-1.04), but no significant relationship was found for PM1-2.5. In conclusion, the present study demonstrated long-term exposure to PM1 was associated with an increased risk of CKD in the general population and PM1 might play a leading role in the observed relationship of PM2.5 with the risk of CKD. These findings provide crucial evidence for developing air pollution control strategies to reduce the burden of CKD.

Differences Between Cystatin C- and Creatinine-Based Estimated Glomerular Filtration Rate and Association with Mortality and Cardiovascular Events: Results from Three Cohorts of Adults with Diabetes.

BACKGROUND AND HYPOTHESIS: To explore the association between the differences between cystatin C- and creatinine-based estimated glomerular filtration rate (eGFRdiff) with the risk of mortality and cardiovascular (CV) events in individuals with diabetes. METHODS: Three prospective cohorts analyzed data of adults with diabetes from the Incident, Development, and Prognosis of Diabetic Kidney Disease (INDEED) study (2016-2017 to 2020) in China, the National Health, Nutrition Examination Survey (NHANES, 1999-2004 to 2019) in the United States, and UK Biobank (UKB, 2006-2010 to 2022). Baseline eGFRdiff was calculated using both absolute difference between cystatin C- and creatinine-based calculations (eGFRabdiff), and the ratio between them (eGFRrediff). Cox proportional hazards regression models were used to investigate the association between eGFRdiff and outcomes including all-cause mortality and incident CV events. RESULTS: A total of 8,129 individuals from the INDEED (aged 60.7±10.0 years), 1,634 from the NHANES (aged 62.5±14.4 years), and 29,358 from the UKB (aged 59.4±7.3 years;) were included. At baseline, 43.6%, 32.4% and 42.1% of participants in the INDEED, NHANES and UKB had an eGFRabdiff value ≥15 ml/min/1.73 m2. During a median follow-up of 3.8 years for the INDEED, 15.2 years for the NHANES, and 13.5 years for the UKB, a total of 430, 936 and 6143 deaths and a total of 481, 183 and 5583 CV events occurred, respectively. Each 1-standard deviation higher baseline eGFRabdiff was independently associated with a lower risk of all-cause mortality and CV events, with hazard ratios (HRs) of 0.77 and 0.82 in the INDEED, 0.70 and 0.68 in the NHANES, and 0.66 and 0.78 in the UKB. Similar results were observed for eGFRrediff. CONCLUSIONS: eGFRdiff represents a marker of adverse events for diabetes among general population. Monitoring both eGFRcys and eGFRcr yields additional prognostic information and has clinical utility in identifying high-risk individuals for mortality and CV events.

Ambient PM2.5 components and prevalence of chronic kidney disease: a nationwide cross-sectional survey in China.

OBJECTIVES: Chronic kidney disease (CKD) is a global public health concern, and accumulating evidence has indicated that air pollution increases the odds of CKD. However, a limited number of studies have examined the long-term effects of ambient fine particulate matter (PM2.5) components on the risk of CKD among general population; thus, major knowledge gaps remain. METHODS: Using data from a nationwide representative cross-sectional survey in China and a validated PM2.5 composition dataset, we established generalized linear models to quantify the association between five major components of PM2.5 and CKD prevalence. RESULTS: There were significant associations between long-term exposure to three PM2.5 components [including black carbon (BC), sulfate (SO42-), organic matter (OM)] and increased odds of CKD prevalence. Along with an interquartile range (IQR) increment in BC (3.3 µg/m3), SO42- (9.7 µg/m3), and OM (16.2 µg/m3) at a 4-year moving average, the odds ratios (ORs) for CKD prevalence were 1.28 (95% CI 1.07, 1.54), 1.23 (95% CI 1.03, 1.45), and 1.23 (95% CI 1.02, 1.47), respectively. We did not detect any significant association of the other two PM2.5 components [nitrate (NO3-) or ammonium (NH4+)] with CKD prevalence. Stratified analyses revealed no differences (P ≥ 0.05) in the effect estimates of subgroups based on administrative region, sex, age, and other demographic characteristics. For instance, along with an IQR increment in BC at a 4-year moving average, the ORs of CKD prevalence among males and females were 1.30 (95% CI 0.98, 1.73) and 1.29 (95% CI 1.01, 1.65), respectively. The odds of CKD were generally higher with increasing PM2.5 composition concentration. CONCLUSIONS: Our study demonstrated that long-term exposure to specific PM2.5 components including BC, SO42-, and OM increased CKD risk in the general population. This study could provide new insights into source-directed PM2.5 control and CKD prevention.

Air pollution and the risk of incident chronic kidney disease in patients with diabetes: An exposure-response analysis.

Impact of air pollution on incident chronic kidney disease (CKD) in diabetic patients is insufficiently studied. We aimed to examine exposure-response associations of PM2.5, PM10, PM2.5-10, NO2, and NOX with incident CKD in diabetic patients in the UK. We also widened exposure level of PM2.5 and examined PM2.5-CKD association in diabetic patients across the entire range of global concentration. Based on data from UK biobank cohort, we applied Cox proportional hazards models and the shape constrained health impact function to investigate the associations between air pollutants and incident CKD in diabetic patients. Global exposure mortality model was applied to combine the PM2.5-CKD association in diabetic patients in the UK with all other published associations. Multiple air pollutants were positively associated with incident CKD in diabetic patients in the UK, with hazard ratios (HRs) of 1.034 (95 %CI: 1.015-1.053) and 1.021 (95 %CI: 1.007-1.036) for every 1 µg/m3 increase in PM2.5 and PM10 concentration, and 1.113 (95 %CI: 1.053-1.177) and 1.058 (95 %CI: 1.027-1.091) for every 10 µg/m3 increase in NO2 and NOX concentration, respectively. For PM2.5-10, associations with CKD in diabetic patients did not reach the statistical significance. Exposure-response associations with CKD in diabetic patients showed a near-linear trend for PM2.5, PM10, NO2, and NOX in the UK, whereas PM2.5-DKD associations in the globe exhibited a non-linear increasing trend. This study supports that air pollution could significantly increase the risk of CKD onset in diabetic patients.

Hospitalizations of Chronic Dialysis Patients: A National Study in China.

Background: Patients receiving chronic dialysis are usually with multiple comorbidities and at high risk for hospitalization, which lead to tremendous health care resource utilization. This study aims to explore the characteristics of hospitalizations among chronic dialysis patients in China. Methods: Hospital admissions from January 2013 to December 2015 were extracted from a national inpatient database in China. Chronic dialysis, including hemodialysis and peritoneal dialysis, was identified according to inpatient discharge records and International Classification of Diseases-10 (ICD-10) codes. The primary kidney disease, causes of admissions, modalities of dialysis, and comorbidities were analyzed. Multivariable logistic regression model was used to assess the association of patient characteristics with multiple hospitalizations per year. Results: Altogether, 266,636 hospitalizations from 124,721 chronic dialysis patients were included in the study. The mean age was 54.46 ± 15.63 years and 78.29% of them were receiving hemodialysis. The leading cause of hospitalizations was dialysis access-related, including dialysis access creation (25.06%) and complications of access (21.09%). The following causes were nonaccess surgery (1.89%), cardiovascular disease (1.66%), and infectious diseases (1.43%). One-fourth of the patients were hospitalized more than once per year. Multivariate logistic regression models indicated that the primary kidney disease of diabetic kidney disease (odds ratio [OR]: 1.16, 95% confidence interval [CI]: 1.11-1.22) or hypertensive nephropathy (OR: 1.33, 95% CI: 1.27-1.40), coronary heart disease (OR: 1.09, 95% CI: 1.05-1.14), cancer (OR: 1.21, 95% CI: 1.13-1.30), or modality of peritoneal dialysis (OR: 2.67, 95% CI: 2.59-2.75) was risk factors for multiple hospitalizations. Conclusion: Our study described characteristics and revealed the burden of hospitalizations of chronic dialysis patients in China. These findings highlight the importance of effective and efficient management strategies to reduce the high burden of hospitalization in dialysis population.

Association between alkaline phosphatase/albumin ratio and the prognosis in patients with chronic kidney disease stages 1-4: results from a C-STRIDE prospective cohort study.

Background: The alkaline phosphatase-to-albumin ratio (APAR) has been demonstrated to be a promising non-invasive biomarker for predicting prognosis in certain diseases. However, the relationship between APAR and prognosis in non-dialysis chronic kidney disease (CKD) patients remains unclear. This study aims to identify the association between APAR and prognosis among CKD stages 1-4 in China. Methods: Patients with CKD stages 1-4 were consecutively recruited from 39 clinical centers in China from 2011 to 2016. New occurrences of end-stage kidney disease (ESKD), major adverse cardiovascular and cerebrovascular events, and all-cause deaths were the outcome events of this study. Subdistribution hazard competing risk and Cox proportional hazards regression models were adopted. Results: A total of 2,180 participants with baseline APAR values were included in the analysis. In the primary adjusted analyses, higher APAR level [per 1-standard deviation (SD) increase in natural logarithm transformed (ln-transformed) APAR] was associated with 33.5% higher risk for all-cause deaths [adjusted hazard ratio (HR) 1.335, 95% confidence interval (CI) 1.068-1.670]. In addition, there was evidence for effect modification of the association between APAR and ESKD by baseline estimated glomerular filtration rate (eGFR) (P interaction < 0.001). A higher APAR level (per 1-SD increase in ln-transformed APAR) was associated with a greater risk of ESKD among participants with eGFR ≥ 60 ml/min/1.73 m2 (adjusted SHR 1.880, 95% CI 1.260-2.810) but not in eGFR < 60 ml/min/1.73 m2. Conclusion: Higher APAR levels in patients with CKD stages 1-4 seemed to be associated with an increased risk of all-cause death. Thus, APAR appears to be used in risk assessment for all-cause death among patients with CKD stages 1-4.

Heat exposure and hospitalizations for chronic kidney disease in China: a nationwide time series study in 261 major Chinese cities.

BACKGROUND: Climate change profoundly shapes the population health at the global scale. However, there was still insufficient and inconsistent evidence for the association between heat exposure and chronic kidney disease (CKD). METHODS: In the present study, we studied the association of heat exposure with hospitalizations for cause-specific CKD using a national inpatient database in China during the study period of hot season from 2015 to 2018. Standard time-series regression models and random-effects meta-analysis were developed to estimate the city-specific and national averaged associations at a 7 lag-day span, respectively. RESULTS: A total of 768,129 hospitalizations for CKD was recorded during the study period. The results showed that higher temperature was associated with elevated risk of hospitalizations for CKD, especially in sub-tropical cities. With a 1 °C increase in daily mean temperature, the cumulative relative risks (RR) over lag 0-7 d were 1.008 [95% confidence interval (CI) 1.003-1.012] for nationwide. The attributable fraction of CKD hospitalizations due to high temperatures was 5.50%. Stronger associations were observed among younger patients and those with obstructive nephropathy. Our study also found that exposure to heatwaves was associated with added risk of hospitalizations for CKD compared to non-heatwave days (RR = 1.116, 95% CI 1.069-1.166) above the effect of daily mean temperature. CONCLUSIONS: Short-term heat exposure may increase the risk of hospitalization for CKD. Our findings provide insights into the health effects of climate change and suggest the necessity of guided protection strategies against the adverse effects of high temperatures.

Nephrology workforce in China: describing current status and evaluating the optimal capacity based on real-world data.

OBJECTIVE: This study aims to characterize the current status of the nephrology workforce in China and evaluate its optimal capacity based on real-world patient mobility data. METHODS: Data on nephrologists in China were collected from two prominent online healthcare platforms using web crawlers and natural language processing techniques. Hospitalization records of patients with chronic kidney disease (CKD) from January 2014 to December 2018 were extracted from a national administrative database in China. City-level paths of patient mobility were identified. Effects of nephrology workforce on patient mobility were analyzed using multivariate Poisson regression models. RESULTS: Altogether 9.13 nephrologists per million population (pmp) were in practice, with substantial city-level variations ranging from 0.16 to 88.79. The ratio of nephrologists to the estimated CKD population was 84.57 pmp. Among 6 415 559 hospitalizations of patients with CKD, 21.3% were cross-city hospitalizations and 7441 city-level paths of patient mobility with more than five hospitalizations were identified. After making adjustment for healthcare capacity, healthcare insurance, economic status, and travel characteristics, the Poisson regression models revealed that the number of nephrologists in both the source city (incidence rate ratio [IRR] 0.99, per 1 pmp increase) and destination city (IRR 1.07, per 1 pmp increase) were independently associated with patient mobility. An IRR plateau was observed when the number of nephrologists exceeded 12 pmp in the source city, while a rapidly increasing IRR was observed beyond 20 pmp in the destination city. CONCLUSIONS: The nephrology workforce in China exhibits significant geographic variations. Based on local healthcare needs, an optimal range of 12-20 nephrologists pmp is suggested.

Association Between Serum Cystatin C and Cognitive Decline Independently from Creatinine: Evidence from Two Nationally Representative Aging Cohorts.

BACKGROUND: Studies on the association between cystatin C based estimated glomerular filtration rate (eGFRcys) and cognitive outcomes yielded inconsistent results. OBJECTIVE: The present study aimed to examine the potential association of eGFRcys with subsequent cognitive decline rate. METHODS: A total of 11,503 community-based participants were involved in our analyses, including 5,837 (aged 72.9±6.3; 58.6% women) in the Health and Retirement Study (HRS) from the US and 5,666 (aged 58.1±9.2; 49.0% women) in the China Health and Retirement Longitudinal Study (CHARLS). The association of eGFRcys with subsequent cognitive decline rate was evaluated by linear mixed models. RESULTS: During 85,266 person-years of follow-up, both baseline elevated serum cystatin C (-0.048 standard deviation [SD]/year per mg/L; 95% confidence interval [CI], -0.060 to -0.036; p < 0.001) and decreased eGFRcys (0.026 SD/year per 30 mL/min/1.73m2; 95% CI, 0.020 to 0.032; p < 0.001) were associated with faster cognitive decline rate after full adjustment. Compared with those had eGFRcys ≥90 mL/min/1.73m2, participants with eGFRcys between 60 to 90 mL/min/1.73m2 (-0.012 SD/year; 95% CI, -0.020 to -0.004; p = 0.004) and those with eGFRcys <60 mL/min/1.73m2 (-0.048 SD/year; 95% CI, -0.058 to -0.039; p < 0.001) experienced statistically significantly faster cognitive decline after adjustment. The associations were independent from serum creatinine/eGFRcre (eGFR that was calculated from serum creatinine). CONCLUSION: Decreased eGFRcys are significantly associated with faster cognitive decline after full adjustment, independently from serum creatinine/eGFRcre. Serum cystatin C might be a risk factor or a prodromal biomarker of cognitive decline.

Self-sovereign identity empowered non-fungible patient tokenization for health information exchange using blockchain technology.

BACKGROUND: Patient tokenization is a novel approach that allows anonymous patient-level linkage across healthcare facilities, minimizing the risk of breaching protected health information in health information exchange (HIE). Most patient tokenization is the centralized approach that is unable to address data security concerns fundamentally. Non-Fungible Tokens (NFT), which are non-transferable cryptographic assets on the blockchain, have the potential to provide secure, decentralized, and trustworthy patient tokenization. Self-Sovereign Identity (SSI) is a user-centric approach to verify the ownership of NFTs in a decentralized manner. METHODS: We have developed a blockchain architecture that contains four modules: (1) Creation module for NFTs creation, (2) Linkage module to link the local patients' accounts to their NFTs, (3) Authentication module that allows patients to permit healthcare providers to access their token, and (4) Exchange module, which involves the HIE process and the validation of the legitimacy of the token through SSI. RESULTS: A case study has been conducted on the proposed architecture. Over 3 million transactions have been completed successfully with a blockchain validation and written time of 1.17 s on average. A stability test has also been conducted with a higher throughput of 200 transactions per second running for an hour with an average transaction processing time of 1.42 s. CONCLUSIONS: This study proposed a blockchain architecture that achieves SSI-enabled NFT-based patient tokenization. Our architecture design, implementation, and case studies have demonstrated the feasibility and potential of NFT with SSI to establish a secure, transparent, and patient-centric identity management and HIE.

ESKD Risk Prediction Model in a Multicenter Chronic Kidney Disease Cohort in China: A Derivation, Validation, and Comparison Study.

BACKGROUND AND OBJECTIVES: In light of the growing burden of chronic kidney disease (CKD), it is of particular importance to create disease prediction models that can assist healthcare providers in identifying cases of CKD individual risk and integrate risk-based care for disease progress management. The objective of this study was to develop and validate a new pragmatic end-stage kidney disease (ESKD) risk prediction utilizing the Cox proportional hazards model (Cox) and machine learning (ML). DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: The Chinese Cohort Study of Chronic Kidney Disease (C-STRIDE), a multicenter CKD cohort in China, was employed as the model's training and testing datasets, with a split ratio of 7:3. A cohort from Peking University First Hospital (PKUFH cohort) served as the external validation dataset. The participants' laboratory tests in those cohorts were conducted at PKUFH. We included individuals with CKD stages 1~4 at baseline. The incidence of kidney replacement therapy (KRT) was defined as the outcome. We constructed the Peking University-CKD (PKU-CKD) risk prediction model employing the Cox and ML methods, which include extreme gradient boosting (XGBoost) and survival support vector machine (SSVM). These models discriminate metrics by applying Harrell's concordance index (Harrell's C-index) and Uno's concordance (Uno's C). The calibration performance was measured by the Brier score and plots. RESULTS: Of the 3216 C-STRIDE and 342 PKUFH participants, 411 (12.8%) and 25 (7.3%) experienced KRT with mean follow-up periods of 4.45 and 3.37 years, respectively. The features included in the PKU-CKD model were age, gender, estimated glomerular filtration rate (eGFR), urinary albumin-creatinine ratio (UACR), albumin, hemoglobin, medical history of type 2 diabetes mellitus (T2DM), and hypertension. In the test dataset, the values of the Cox model for Harrell's C-index, Uno's C-index, and Brier score were 0.834, 0.833, and 0.065, respectively. The XGBoost algorithm values for these metrics were 0.826, 0.825, and 0.066, respectively. The SSVM model yielded values of 0.748, 0.747, and 0.070, respectively, for the above parameters. The comparative analysis revealed no significant difference between XGBoost and Cox, in terms of Harrell's C, Uno's C, and the Brier score (p = 0.186, 0.213, and 0.41, respectively) in the test dataset. The SSVM model was significantly inferior to the previous two models (p < 0.001), in terms of discrimination and calibration. The validation dataset showed that XGBoost was superior to Cox, regarding Harrell's C, Uno's C, and the Brier score (p = 0.003, 0.027, and 0.032, respectively), while Cox and SSVM were almost identical concerning these three parameters (p = 0.102, 0.092, and 0.048, respectively). CONCLUSIONS: We developed and validated a new ESKD risk prediction model for patients with CKD, employing commonly measured indicators in clinical practice, and its overall performance was satisfactory. The conventional Cox regression and certain ML models exhibited equal accuracy in predicting the course of CKD.

Trends of Urolithiasis in China: A National Study Based on Hospitalized Patients from 2013 to 2018.

Introduction: The aim of this study was to explore the chronological trends in clinical features and utilization of healthcare resources for hospitalized patients with urolithiasis in China. Methods: Patients with urolithiasis were extracted from the Hospital Quality Monitoring System, a national database of hospitalized patients in China, based on the International Classification of Diseases, Tenth Revision, codes. Variables including demographic characteristics, comorbidities, treatment modalities for urolithiasis, length of hospital stay, and expenditures were collected and analyzed. Results: Among 79.8 million hospitalized patients, 3.5 million were diagnosed with urolithiasis with an increasing trend (from 3.0% in 2013 to 4.0% in 2018). Most of these patients had upper urinary tract calculi (76.6% in 2013 and 81.7% in 2018). Middle-aged patients (46-65 years) constituted the largest proportion with a stable trend (from 46.9% in 2013 to 48.8% in 2018), while the proportion of older patients (>65 years) showed an increasing trend (from 23.7% in 2013 to 27.4% in 2018). The percentages of gout/hyperuricemia, hypertension, diabetes, and cardiovascular disease among the hospitalized patients with urolithiasis increased steadily, with the sharpest increases in patients from rural areas. Overall, 656,952 patients (18.9%) received surgical interventions for urolithiasis. The proportions of ureteroscopy and extracorporeal shockwave lithotripsy increased steadily during the 6-year study period, with simultaneous decreases in open surgery and percutaneous nephrolithotomy. The median length of hospital stay decreased from 10 days to 8 days. The cost of urolithiasis intervention accounted for 2.0% of the total hospitalization fee in 2013 and increased to 2.7% in 2018. Conclusions: The analysis showed an increasing trend in the percentage of hospitalized patients with urolithiasis, accompanied by an increased percentage of the total hospitalization fee for urolithiasis intervention during the 6-year study period. Based on the increasing trends in the proportion of older patients (>65 years) and percentages of metabolic comorbidities among patients with urolithiasis, an increased burden of urolithiasis on the healthcare system in China is anticipated.

Regional urbanicity levels modify the association between ambient air pollution and prevalence of obesity: A nationwide cross-sectional survey.

Ambient air pollution exposure may increase the risk of obesity, but the population susceptibility associated with urbanicity has been insufficiently investigated. Based on a nationwide representative cross-sectional survey on 44,544 adults, high-resolution night light satellite remote sensing products, and multi-source ambient air pollution inversion data, the present study evaluated the associations of fine particulate matter (PM2.5) and nitrogen dioxide (NO2) concentrations with the prevalence of obesity and abdominal obesity. We further calculated the associations in regions with different urbanicity levels characterized by both administrative classification of urban/rural regions and night light index (NLI). We found that 10 µg/m3 increments in PM2.5 at 1-year moving average and in NO2 at 5-year moving average were associated with increased prevalence of obesity [odds ratios (OR) = 1.16 (1.14, 1.19); 1.12 (1.09, 1.15), respectively] and abdominal obesity [OR = 1.08 (1.07, 1.10); 1.07 (1.05, 1.09), respectively]. People in rural regions experienced stronger adverse effects than those in urban regions. For instance, a 10 µg/m3 increment in PM2.5 was associated with stronger odds of obesity in rural regions than in urban regions [OR = 1.27 (1.23, 1.31) vs 1.10 (1.05, 1.14), P for interaction <0.001]. In addition, lower NLI values were associated with constantly amplified associations of PM2.5 and NO2 with obesity and abdominal obesity (all P for interaction <0.001). In summary, people in less urbanized regions are more susceptible to the adverse effects of ambient air pollution on obesity, suggesting the significance of collaborative planning of urbanization development and air pollution control, especially in less urbanized regions.