Earth-abundant Li-ion cathode materials with nanoengineered microstructures.

Manganese-based materials have tremendous potential to become the next-generation lithium-ion cathode as they are Earth abundant, low cost and stable. Here we show how the mobility of manganese cations can be used to obtain a unique nanosized microstructure in large-particle-sized cathode materials with enhanced electrochemical properties. By combining atomic-resolution scanning transmission electron microscopy, four-dimensional scanning electron nanodiffraction and in situ X-ray diffraction, we show that when a partially delithiated, high-manganese-content, disordered rocksalt cathode is slightly heated, it forms a nanomosaic of partially ordered spinel domains of 3-7 nm in size, which impinge on each other at antiphase boundaries. The short coherence length of these domains removes the detrimental two-phase lithiation reaction present near 3 V in a regular spinel and turns it into a solid solution. This nanodomain structure enables good rate performance and delivers 200 mAh g-1 discharge capacity in a (partially) disordered material with an average primary particle size of ∼5 µm. The work not only expands the synthesis strategies available for developing high-performance Earth-abundant manganese-based cathodes but also offers structural insights into the ability to nanoengineer spinel-like phases.

E-cigarette use and associated factors among adults aged 18-44 years in China: Findings from an online survey.

INTRODUCTION: There needs to be more up-to-date evidence on the prevalence of e-cigarette use among Chinese adults. This study aims to investigate the prevalence and associated factors of e-cigarette use among adults aged 18-44 years in China. METHODS: Cross-sectional design and convenience sampling were used. The data for this study were obtained from an online survey conducted in mainland China from April to May 2023. The target population was adults aged 18-44 years. Descriptive analysis was employed to report the prevalence of e-cigarette use, while adjusted multivariable logistic regression was performed to examine the association between e-cigarette use and related factors. RESULTS: A total of 4256 participants were included in this study; 12.9% were current e-cigarette users, 5.9% were frequent users, and 7.0% were occasional users. The descriptive analysis results indicated that males and cigarette users had a higher prevalence of e-cigarette use. Multivariable analysis showed that e-cigarette use was significantly associated with female gender (AOR=0.76, 95% CI: 0.60-0.96), those aged 25-34 years with monthly income 6000-8999 CNY (AOR=2.01; 95% CI: 1.18-3.41), those aged 25-34 years with monthly income ≥9000 CNY (AOR=2.20; 95% CI: 1.26-3.82), college or undergraduate degree (AOR=1.91; 95% CI: 1.22-3.00), urban residence (AOR=1.72; 95% CI: 1.34-2.20), being a current smoker (AOR=3.32; 95% CI: 2.64-4.16), perception of harm (AOR=0.66; 95% CI: 0.60-0.73), and perception of benefit (AOR=2.31; 95% CI: 2.04-2.61). CONCLUSIONS: The prevalence of current e-cigarette use among adults in China was 12.9% within our sample. In addition to sociodemographic factors, individuals with a higher perception of the harm associated with e-cigarettes were less likely to engage in e-cigarette consumption. Conversely, individuals who perceive the 'benefits' of e-cigarettes more favorably use them. Targeted interventions, such as health education, are recommended to help adults develop a correct understanding of e-cigarettes and lower the prevalence of e-cigarette use.

Estimating trans-ancestry genetic correlation with unbalanced data resources.

The aim of this paper is to propose a novel method for estimating trans-ancestry genetic correlations in genome-wide association studies (GWAS) using genetically-predicted observations. These correlations describe how genetic architecture of complex traits varies among populations. Our new estimator corrects for biases arising from prediction errors in high-dimensional weak GWAS signals, while addressing the ethnic diversity inherent in GWAS data, such as linkage disequilibrium (LD) differences. A distinguishing feature of our approach is its flexibility regarding sample sizes: it necessitates a large GWAS sample only from one population, while the secondary population may have a much smaller cohort, even in the hundreds. This design directly addresses the existing imbalance in GWAS data resources, where datasets for European populations typically outnumber those of non-European ancestries. Through extensive simulations and real data analysis from the UK Biobank study encompassing 26 complex traits, we validate the reliability of our method. Our results illuminate the broader implications of transferring genetic findings across diverse populations.

Neuroelectrophysiological alteration associated with cognitive flexibility after 24 h sleep deprivation in adolescents.

The cognitive neural mechanisms by which sleep deprivation affects cognitive flexibility are poorly understood. Therefore, the study investigated the neuroelectrophysiological basis of the effect of 24 h sleep deprivation on cognitive flexibility in adolescents. 72 participants (36 females, mean age ± SD=20.46 ± 2.385 years old) participated in the study and were randomly assigned to the sleep deprivation group and control group. They were instructed to complete a task switch paradigm, during which participants' behavioral and electroencephalographic data were recorded. Behaviorally, there were significant between-group differences in accuracy. The results of event-related potential showed that the P2, N2 and P3 components had significant group effects or interaction effects. At the time-frequency level, there were statistically significant differences between the delta and theta bands. These results suggested that 24 h sleep deprivation affected problem-solving effectiveness rather than efficiency, mainly because it systematically impaired cognitive processing associated with cognitive flexibility.

Prevalence and Incidence of Hepatitis E Infection in China.

BACKGROUND AND AIMS: China is an endemic area for hepatitis E virus (HEV) infection. Estimating the prevalence and incidence of HEV infection in China plays a pivotal role in informing public health policies to prevent and control hepatitis E. This study aimed to investigate the prevalence of anti-HEV IgG and incidence of HEV seroconversion in China. METHODS: This study was based on the Meinian health check-up database in China. Participants who underwent testing for anti-HEV IgG at check-up centers in 24 provinces between 2017 and 2022 were included. In the cross-sectional analyses, overall prevalence and stratified prevalence in subpopulations with various characteristics were estimated and standardized according to the 2020 census of the Chinese population. In the longitudinal analyses, the occurrence of anti-HEV IgG positivity during the follow-up was defined as an incident HEV seroconversion. Overall and stratified incidence rates were estimated and expressed as per 100 person-years. Poisson regression was used to explore risk factors associated with HEV seroconversion. RESULTS: A total of 85,238 and 11,154 participants were included in the cross-sectional and longitudinal analyses, respectively. The prevalence of anti-HEV IgG in the general population was 18.02%. During a median follow-up of 1.2 years, the incidence rate of HEV seroconversion was 1.79 per 100 person-years. Age ≥60 years, low socioeconomic status, living in coastal areas, living in areas with high drainage density, and living in areas with high anti-HEV IgG prevalence were independent risk factors for HEV seroconversion. CONCLUSIONS: Our findings would help inform policymaking for hepatitis E prevention and control in China as well as in other endemic regions of the world.

Adherence to a Healthy Diet and Risk of Multiple Carotid Atherosclerosis Subtypes: Insights from the China MJ Health Check-Up Cohort.

AIM: Early-stage phenotypes of carotid atherosclerosis (CAS), such as increased carotid intima-media thickness (cIMT), and advanced-stage phenotypes, such as carotid plaque (CP), are at risk for adverse ischemic stroke events. There is limited evidence regarding the causal association between dietary patterns and the risk of CAS in Chinese adults. We therefore examined multiple dietary patterns associated with the risk of CAS and identified the optimal dietary pattern for preventing CAS. METHODS: We analyzed data collected from the prospective MJ Health Check-up Study (2004-2020), including 13,989 participants 18-80 years of age without CAS. The dietary intake was measured using validated food frequency questionnaires, and dietary pattern scores were calculated for four a priori and four a posteriori dietary patterns. The Cox model was used to estimate the adjusted hazard ratios (HRs) relating various dietary pattern scores to the risk of CAS. RESULTS: During 43,903.4 person-years of follow-up, 3732 incidents of increased cIMT and 2861 incident CP events were documented. Overall, the seven dietary patterns, except for the high-protein diet, exhibited significant associations with the risk of increased cIMT and CP. Comparing the highest and lowest quartiles, the a posteriori high-fiber dietary pattern (HFIDP) score demonstrated the strongest inverse associations with the risk of increased cIMT (HR 0.65 [95% confidence interval (CI) 0.59-0.71]) and CP (HR 0.65 [95% CI 0.59-0.73]); conversely, another a posteriori high-fat dietary pattern (HFADP; i.e., incorporating high-fat and processed foods) demonstrated the strongest positive associations with the risk of increased cIMT (HR 1.96 [95% CI 1.75-2.20]) and CP (HR 1.83 [95% CI 1.61-2.08]) (all p for trend < 0.01). CONCLUSIONS: Multiple dietary patterns are significantly associated with the risk of early- and advanced-stage phenotypes of CAS. Notably, a high adherence to an HFIDP and low adherence to an HFADP may confer the greatest risk reduction for CAS.

The Structural Characterization of a Polysaccharide from the Dried Root of Salvia miltiorrhiza and Its Use as a Vaccine Adjuvant to Induce Humoral and Cellular Immune Responses.

In order to supplement the research gap concerning Salvia miltiorrhiza polysaccharide extracted from Danshen in NMR analysis, and to clarify its immune enhancement effect as an adjuvant, we isolated and purified SMPD-2, which is composed of nine monosaccharides such as Ara, Gal, and Glc from Danshen. Its weight average molecular weight was 37.30 ± 0.096 KDa. The main chain was mainly composed of →4)-α-D-Galp-(1→, →3,6)-ß-D-Glcp-(1→ and a small amount of α-L-Araf-(1→. After the subcutaneous injection of SMPD-2 as an adjuvant to OVA in mice, we found that it enhanced the immune response by activating DCs from lymph nodes, increasing OVA-specific antibody secretion, stimulating spleen lymphocyte activation, and showing good biosafety. In conclusion, SMPD-2 could be a promising candidate for an adjuvant.

Eye-brain connections revealed by multimodal retinal and brain imaging genetics.

The retina, an anatomical extension of the brain, forms physiological connections with the visual cortex of the brain. Although retinal structures offer a unique opportunity to assess brain disorders, their relationship to brain structure and function is not well understood. In this study, we conducted a systematic cross-organ genetic architecture analysis of eye-brain connections using retinal and brain imaging endophenotypes. We identified novel phenotypic and genetic links between retinal imaging biomarkers and brain structure and function measures from multimodal magnetic resonance imaging (MRI), with many associations involving the primary visual cortex and visual pathways. Retinal imaging biomarkers shared genetic influences with brain diseases and complex traits in 65 genomic regions, with 18 showing genetic overlap with brain MRI traits. Mendelian randomization suggests bidirectional genetic causal links between retinal structures and neurological and neuropsychiatric disorders, such as Alzheimer's disease. Overall, our findings reveal the genetic basis for eye-brain connections, suggesting that retinal images can help uncover genetic risk factors for brain disorders and disease-related changes in intracranial structure and function.

[Application of the cigarette purchase tasks in achieving China' s tobacco control goals].

OBJECTIVE: To assess cigarette demand among Chinese smokers through a cigarette purchase task (CPT) and to evaluate cigarette prices under different hypothetical scenarios in order to meet the goals of smoking prevalence reduction in China. METHODS: In the study, 447 participants completed a hypothetical CPT at baseline assessments of a trial, thus, cigarette demand curves were individually fitted for each participant using an exponentiated version of the exponential demand model. Typically, five demand indices were derived, intensity (consumption when free), breakpoint (first price at which consumption is suppressed to 0), maximum output (Omax), maximum price (Pmax, price at which Omax occurred), and elasticity (the ratio of the change in quantity demanded to the change in price). A one-way analysis of variance was used to explore the correlations between the cigarette purchase task indices and socio-demographic and smoking characteristics. The one-way decay model was employed to simulate the smoking cessation rates and determine optimal cigarette prices in a series of scenarios for achieving 20% smoking prevalence. RESULTS: The price elasticity drawn from CPT was 0.54, indicating that a 10% price increase could reduce smoking by 5.4% in the participated smokers. Smokers with higher income were less sensitive to cigarette prices (elasticity=-2.31, P=0.028). Cigarette purchase task indices varied significantly among the smokers with different prices of commonly used cigarettes, tobacco dependence, and smoking volume. The smokers who consumed cigarettes of higher prices reported higher breakpoint, Omax and Pmax, but lower intensity (P=0.001). The smokers who were moderately or highly nicotine dependent reported higher intensity, breakpoint, Omax and Pmax, and they had lower intensity (P=0.001). The smokers who had a higher volume of cigarettes reported higher intensity and Omax, and lower intensity (P < 0.001). To achieve the goal of reducing smoking prevalence to 20% in mainland China, we estimated the desired increase on smoking cessation rate and prices accordingly in a series of scenarios, considering the gender variance and reduced smoking initiation. In scenario (a), to achieve a smoking prevalence goal of 20%, it would be necessary for 24.81% of the current smokers to quit smoking when there were no new smokers. Our fitting model yielded a corresponding value of 59.64 yuan (95%CI 53.13-67.24). Given the assumption in scenario (b) that only males quitted smoking, the desired cessation rates would be 25.82%, with a higher corresponding price of 62.15 yuan (95%CI 55.40-70.06) to induce desired cessation rates. In the proposed scenario (c) where 40 percent of the reduction in smoking prevalence came from reduced smoking initiation, and females and males equally quitted smoking due to increased cigarette prices, the price of a pack of cigarettes would be at least 37.36 yuan (95%CI 32.32-42.69) (equals to $ 5.20) per pack to achieve the cessation rate of 14.89 percent. In scenario (d) where only males quitted smoking due to increased cigarette prices considering the reduced smoking initiation, the respective smoking cessation rates should be 15.49% with the desired prices of 38.60 yuan (95%CI 33.53-44.02). After adjusting for education levels and income levels in scenario (c), the price of cigarettes would be at least 37.37 yuan/pack (equals to $ 5.20) (95%CI 30.73-44.94) and 37.84 yuan/pack (equals to $ 5.26) (95%CI 31.94-44.53), respectively. CONCLUSION: Cigarette purchase task indices are significantly associated with income levels and prices of commonly used cigarettes, levels of tobacco dependence, and smoking volume, which is inspiring in studying price factors that influence smoking behavior. It is suggested that higher cigarette prices, surpassing the current actual market level, is imperative in mainland China. Stronger policy stra-tegies should be taken to increase tobacco taxes and retail cigarette prices to achieve the Healthy China 2030 goal of reducing smoking prevalence to 20%.

Graphdiyne-Induced CoN/CoS2 Heterojunction: Boosting Efficiency for Bifunctional Oxygen Electrochemistry in Zinc-Air Batteries.

The performance of zinc-air battery is constrained by the sluggish rate of oxygen electrode reaction, particularly under high current discharge conditions where the kinetic process of the oxygen reduction reaction (ORR) decelerates significantly. To address this challenge, we present a novel phase transition strategy that facilitates the creation of a heteroatom-doped heterointerface (CoN/CoS2). The meticulously engineered CoN/CoS2/NC electrocatalyst displays a superior ORR half-wave potential of 0.87 V and an OER overpotential of 320 mV at 10 mA cm-2. Experimental and computational analysis confirm that the CoN/CoS2 heterostructure optimizes local charge distribution, accelerates electron transfer, and tunes active sites for enhanced catalysis. Notably, this heterojunction improves stability by resisting corrosion and degradation under harsh alkaline conditions, thus demonstrating superior performance and longevity in a custom-made liquid zinc-air battery. This research provides valuable practical and theoretical foundations for designing efficient heterointerfaces in electrocatalysis applications.

Genetically Encoded Photocaged Proteinogenic and Non-Proteinogenic Amino Acids.

Photocaged amino acids could be genetically encoded into proteins via genetic code expansion (GCE) and constitute unique tools for innovative protein engineering. There are a number of photocaged proteinogenic amino acids that allow strategic conversion of proteins into their photocaged variants, thus enabling spatiotemporal and non-invasive regulation of protein functions using light. Meanwhile, there are a hand of photocaged non-proteinogenic amino acids that address the challenges in directly encoding certain non-canonical amino acids (ncAAs) that structurally resemble proteinogenic ones or possess highly reactive functional groups. Herein, we would like to summarize the efforts in encoding photocaged proteinogenic and non-proteinogenic amino acids, hoping to draw more attention to this fruitful and exciting scientific campaign.

Multi-organ imaging-derived polygenic indexes for brain and body health.

The UK Biobank (UKB) imaging project is a crucial resource for biomedical research, but is limited to 100,000 participants due to cost and accessibility barriers. Here we used genetic data to predict heritable imaging-derived phenotypes (IDPs) for a larger cohort. We developed and evaluated 4,375 IDP genetic scores (IGS) derived from UKB brain and body images. When applied to UKB participants who were not imaged, IGS revealed links to numerous phenotypes and stratified participants at increased risk for both brain and somatic diseases. For example, IGS identified individuals at higher risk for Alzheimer's disease and multiple sclerosis, offering additional insights beyond traditional polygenic risk scores of these diseases. When applied to independent external cohorts, IGS also stratified those at high disease risk in the All of Us Research Program and the Alzheimer's Disease Neuroimaging Initiative study. Our results demonstrate that, while the UKB imaging cohort is largely healthy and may not be the most enriched for disease risk management, it holds immense potential for stratifying the risk of various brain and body diseases in broader external genetic cohorts.

Financial incentive interventions for smoking cessation among Chinese smokers: study protocol for a cluster randomised controlled trial.

INTRODUCTION: There is an urgent issue to relieve the burdens caused by tobacco use through feasible and effective smoking cessation interventions, particularly in a middle-income country with less accessible smoking cessation services and high demand for quitting smoking. Financial incentives have shown effective in changing health behaviours, thus needing to test its portability to a wider implementation and effectiveness of increasing smoking cessation rates. METHODS AND ANALYSIS: This is a three-arm cluster randomised controlled trial. 462 eligible participants will be assigned to 2 financial incentive groups-rewards or deposits, or the control group. All participants including those in the control group will receive text messages to help quitting smoking developed by the US National Cancer Institute over a 3-month intervention period. In addition to text messages, reward group participants will be rewarded with CNY200 and CNY400 (CNY100 approximately US$15) for sustained smoking abstinence at 1 month and 3 months follow-up assessments; participants in the deposit group will accumulate CNY200 and CNY600 in the deposit accounts after verified smoking abstinence at 1 month and 3 months follow-up assessments, and all the deposits will be given at once right after the 3-month follow-up visit. The primary outcome is biochemically verified smoking abstinence rate sustained for 6 months after enrolment. ETHICS AND DISSEMINATION: This trial protocol has been approved by the Ethics Committee of Peking University Health Science Centre (date: 23 February 2023; ethical approval number: IRB00001052-22172). Results and findings of this trial will be disseminated in peer-reviewed journals and professional conferences. TRIAL REGISTRATION NUMBER: ChiCTR-IOR-2300069631.

Carbon wet deposition flux and river carbon output in a forest watershed in permafrost region of the Da Xing'an Mountains.

Carbon wet deposition and river carbon output in river basins are important components of global carbon cycle. The assessment of both properties is of great significance for regional carbon budget. However, research on these topics in high-latitude permafrost regions in China is still lacking. We conducted dynamic monitoring of carbon wet deposition and carbon output in the river from May 28th to October 30th, 2022, in Laoyeling watershed, a typical forested watershed in the Da Xing'an Mountains permafrost region. We analyzed the variations of carbon component concentrations and fluxes in precipitation and river water, and estimated the contribution of carbon wet deposition to carbon output in the watershed. The results showed that wet deposition fluxes of dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), and total dissolved carbon (TDC) in the Laoyeling watershed were 1354.86, 684.59, and 2039.45 kg·km-2, respectively. The fluxes of DOC, DIC, TDC, particulate organic carbon (POC), particulate inorganic carbon (PIC), and total carbon (TC) in the river were 601.75, 1977.30, 2579.05, 125.13, 21.99, and 2726.17 kg·km-2, respectively. The contribution of TDC wet deposition to the river TDC output was 9941.89 kg, accounting for 17.6% of total output. The DIC concentration in the river showed significant seasonal differences, with increased runoff resulting from precipitation leading to a decrease in DIC concentration in the river and showing a clear dilution effect, while the concentrations of DOC, POC, and PIC increased, mainly due to erosion effect. In conclusion, carbon wet deposition flux in the Laoyeling watershed was mainly determined by precipitation, and its contribution to river carbon output was relatively small compared to other factor. Runoff was the dominant factor affecting river carbon output. The results would provide important insights into carbon cycling and carbon budget balance in permafrost regions under climate change.

Analyzing bivariate cross-trait genetic architecture in GWAS summary statistics with the BIGA cloud computing platform.

As large-scale biobanks provide increasing access to deep phenotyping and genomic data, genome-wide association studies (GWAS) are rapidly uncovering the genetic architecture behind various complex traits and diseases. GWAS publications typically make their summary-level data (GWAS summary statistics) publicly available, enabling further exploration of genetic overlaps between phenotypes gathered from different studies and cohorts. However, systematically analyzing high-dimensional GWAS summary statistics for thousands of phenotypes can be both logistically challenging and computationally demanding. In this paper, we introduce BIGA (https://bigagwas.org/), a website that aims to offer unified data analysis pipelines and processed data resources for cross-trait genetic architecture analyses using GWAS summary statistics. We have developed a framework to implement statistical genetics tools on a cloud computing platform, combined with extensive curated GWAS data resources. Through BIGA, users can upload data, submit jobs, and share results, providing the research community with a convenient tool for consolidating GWAS data and generating new insights.

Poor condyle position after mandibular reconstruction and a classification system for patients with "VSCU" based on computed tomography: a cross-sectional study with retrospective data collection.

Background: Although the application of vascularized free bone muscle flap to reconstruct the mandible has become a standardized approach for mandible reconstruction, the results of its reconstruction are not always satisfactory. The purpose of this study was to identify the types of mandibular and condylar defects by analyzing the unsatisfactory cases of mandibular reconstruction in clinical practice, and to provide some clinical experience of reconstruction. Methods: Our study retrospectively analyzed 364 patients who underwent mandibular resection and vascularized free bone flap reconstruction of the mandible and temporomandibular joint (TMJ). We innovatively proposed a "VSCU" classification system (V: vertical position, S: sagittal position, C: coronal position, U: condylar resection is not required) by analyzing computed tomography (CT) scans of mandibular branches and TMJs. Results: In all, 221 cases of free iliac muscle flap and 143 cases of fibula muscle flap were included in this study, of which 23 cases had unsatisfactory results after TMJ reconstruction. We classified 23 patients with unsatisfactory mandibular reconstruction according to the "VSCU" classification system. The most common type was U + V + SfC (n=8), followed by V - SfC + U + (n=4), V - s + C + U + (n=3), V - sbcou - (n=3), V - SBC + U + (n=2), V - s + C + U - (n=1). The most common classification was insufficient mandibular rami length, followed by condylar sagittal anteriorization. There was no significant change in the position of condyle on the healthy side during mandibular reconstruction involving condyle. P1 on the affected side was 52.28±4.17 mm before operation and 58.94±5.65 mm after operation, P<0.01; P2 was 12.83±3.49 mm before operation and 24.90±7.15 mm after operation. S2 was 4.54±2.84 mm before operation and 19.10±8.54 mm after operation. A2 was 11.46±3.35 mm before operation and 24.15±8.29 mm after operation. The P values were all less than 0.01, and the differences were statistically significant. Conclusions: We propose to use the "VSCU" classification system for accurate 3-dimensional (3D) analysis and positioning, and then obtain accurate models through computer-aided design and manufacturing (CAD/CAM), which can reduce the occurrence of poor reconstruction effect and unreasonable joint position, and is worthy of clinical promotion.

High toxin concentration in pollen may deter collection by bees in butterfly-pollinated Rhododendron molle.

BACKGROUNDS AND AIMS: The hypothesis that plants evolve features that protect accessible pollen from consumption by flower visitors remains poorly understood. METHODS: To explore potential chemical defenses against pollen consumption, we examined the pollinator assemblage, foraging behaviour, visitation frequency and pollen transfer efficiency in Rhododendron molle, a highly toxic shrub containing Rhodojaponin III. Nutrient (protein and lipid) and toxic components in pollen and other tissues were measured. KEY RESULTS: Overall in the five populations, floral visits by butterflies and bumblebees were relatively more frequent than visits by honeybees. All foraged for nectar but not pollen. Butterflies did not differ from bumblebees in the amount of pollen removed per visit, but deposited more pollen per visit. Pollination experiments indicated that R. molle was self-compatible, but both fruit and seed production were pollen limited. Our analysis indicated that the pollen was not protein-poor and had a higher concentration of the toxic compound Rhodojaponin III than petals and leaves, which compound was undetectable in nectar. CONCLUSION: Pollen toxicity in Rhododendron flowers may discourage pollen robbers (bees) from taking the freely accessible pollen grains, while the toxin-free nectar rewards effective pollinators, promoting pollen transfer. This preliminary study supports the hypothesis that chemical defense in pollen would be likely to evolve in species without physical protection from pollinivores.

Association between weight change, waist circumference change, and the risk of nonalcoholic fatty liver disease in individuals with metabolically healthy overweight or obesity and metabolically unhealthy overweight or obesity.

BACKGROUND: This study aimed to explore and compare the effect of weight change, and waist circumference (WC) change, on the risk of nonalcoholic fatty liver disease (NAFLD) in individuals with metabolically healthy overweight or obesity (MHOW/O) and metabolically unhealthy overweight or obesity (MUOW/O) in a health check-up cohort in China. METHODS: 5625 adults with overweight or obesity, and free from NAFLD at baseline were included. Metabolically healthy was defined as not having any components of metabolic syndrome. Weight/WC changes were calculated as the relative difference between the first and second visits of check-up. NAFLD was assessed based on abdominal ultrasound. RESULTS: During a median follow-up of 2.1 (IQR: 1.1-4.3) years, 1849 participants developed NAFLD. In MHOW/O participants, the multivariable adjusted HRs (95 % CIs) for NAFLD in weight change ≤ -5.0 %, and - 4.9-- 1.0 % were 0.36 (0.23-0.59), 0.59 (0.43-0.80), respectively, compared to the weight stable group (-0.9% to 0.9 %). The corresponding HRs (95 % CIs) for the association between WC change (≤ 6.0 %, - 5.9 to -3.0 %) and NAFLD in MHOW/O participants were 0.41 (0.27-0.62), and 0.74 (0.54-1.01), respectively, compared to the WC stable group (-2.9-2.9 %). Similar patterns were observed in MUOW/O participants. A more marked gradient of cumulative incidence of NAFLD across weight/WC change categories was observed in MHOW/O than in MUOW/O individuals. CONCLUSIONS: A more evident association between weight/WC loss and risk of NAFLD was observed in MHOW/O than in MUOW/O individuals. Our findings indicate the practical significance of encouraging all individuals with overweight and obesity to achieve a clinically relevant level of weight/WC loss to prevent NAFLD, even among metabolic healthy groups.