BACKGROUND:Brain metastases (BMs) cause significant mortality in cancer patients. While surgical resection is standard for large or symptomatic lesions, accurate prognostic stratification remains challenging. Existing models often rely on historical data, failing to incorporate the survival impact of modern immune and targeted therapies. This study identifies independent prognostic factors and shares our institutional experience regarding surgical outcomes and multimodal management. METHODS:We analyzed 301 patients who underwent surgical resection for BMs at Beijing Tiantan Hospital (2020-2022) using the NBTRC database. Univariate and multivariate Cox regression analyses were performed to identify predictors of overall survival (OS). A statistical model was constructed to visualize these parameters, and its internal discrimination and calibration were evaluated. RESULTS:Multivariate analysis identified negative OS predictors in order of importance: infratentorial tumor location (HR = 1.896, P < 0.001), multiple metastases (HR = 1.194, P = 0.003), and advancing age (HR = 1.018, P = 0.035). Conversely, postoperative immune/targeted therapy (HR = 0.361, P < 0.001), adjuvant WBRT (HR = 0.671, P = 0.015), and higher discharge KPS (HR = 0.983, P < 0.001) were significant protective factors. An internally validated nomogram (C-index 0.692) confirmed these stratifications. CONCLUSIONS:Based on our institutional experience, surgical resection of BMs has proven to be a safe and effective technique in our hands for carefully selected patients. Furthermore, strict risk stratification-focusing on tumor location, tumor burden, and the integration of modern systemic therapies-is essential for optimizing these real-world clinical outcomes.

OBJECTIVES:The rising global prevalence of electronic cigarette (e-cigarette) use poses significant public health concerns, including nicotine dependence. This systematic review and meta-analysis evaluated the efficacy and safety of pharmacological interventions for e-cigarette cessation. METHODS:We systematically searched 5 databases, including Cochrane Library, PubMed, Ovid Embase, Sinomed, and Web of Science Core Collection, up to May 1, 2024, that evaluated the efficacy and safety of pharmacological intervention compared with placebo for e-cigarette cessation. Two investigators independently screened studies, extracted data, and assessed the risk of bias. The outcomes of interest were (1) continuous abstinence rate (CAR); (2) 7-day point prevalence of e-cigarette abstinence at different weeks; and (3) adverse effects. This study was registered with PROSPERO (CRD42024577356). RESULTS:Of 1567 initially identified records, 7 studies involving 1161 participants were included. Most studies had a low risk of bias. The results indicated that varenicline (4 studies, n=463; OR=2.52, 95% CI: 1.14-5.58) was effective, while the effect of nicotine replacement therapy (NRT; 2 studies, n=538; OR=1.38, 95% CI: 0.61-3.14) was not statistically significant. One study on cytisine also suggested potential benefit. CONCLUSIONS:Varenicline has demonstrated efficacy in supporting e-cigarette cessation, whereas the current evidence for NRT and cytisine remains insufficient to draw firm conclusions. Further well-designed studies are needed to clarify the effectiveness of these 2 interventions. Although pharmacotherapies used for cigarette smoking show potential for repurposing, their utility in e-cigarette cessation should be interpreted cautiously until stronger evidence becomes available.

INTRODUCTION:Smoking is a major preventable cause of morbidity and premature death worldwide. Both bupropion and NRT help achieve smoking cessation. However, evidence on whether the combination of bupropion and NRT is more effective than bupropion alone remains uncertain. The aim of this study was to compare the efficacy and safety of bupropion combined with NRT with bupropion monotherapy. METHODS:The Cochrane Library, Embase, PubMed, and Web of Science were systematically searched for original articles published in English. Randomized controlled trials (RCTs) that compared bupropion plus NRT therapy with bupropion were included. Qualitative and quantitative analyses were conducted and the risk of bias was assessed using the Cochrane Risk of Bias 2 tool. RESULTS:Nine RCTs involving 4005 participants (53.8% female) were included in this study. The mean age across studies ranged from 27 to 55 years. The risk of bias results showed that two RCTs were rated as high, one was low, and six were unclear. Pooled analysis indicated that bupropion combined with NRT significantly improved biochemically validated 7-day point prevalence abstinence at the end of treatment [risk ratio (RR) = 1.35, 95% confidence interval (CI): 1.22-1.50, I2 = 21%]. At long-term follow-up (≥6 months), bupropion plus NRT showed a non-significant benefit over bupropion monotherapy (RR = 1.10, 95% CI: 0.90-1.34, I2 = 52%). Adverse events were generally comparable between groups, except for a higher incidence of nausea in the combination therapy group (10.9% vs. 7.3%; RR = 1.42, 95% CI 1.04-1.94, I2 = 0%). No significant subgroup differences were found based on the types of NRT (nicotine patch, gum, or lozenge) (χ2 = 0.89, p = 0.64). CONCLUSION:Combination therapy of bupropion and NRT was associated with superior short-term smoking cessation outcome compared with bupropion alone, with a comparable safety profile except for increased risk of nausea. However, the long-term benefit of combination therapy over bupropion monotherapy was attenuated and non-significant. Further high-quality RCTs with adequate long-term follow- up are needed to confirm these findings.

BACKGROUND AND AIMS: Evidence on the dual use profile of electronic cigarettes (e-cigarettes) and cigarettes remains limited, especially for the adult population. This study aimed to assess the prevalence and associated factors of lifetime dual use among adults who smoke in China. METHODS: The nationally representative survey of the China Health Literacy Survey (CHLS) was conducted in 2018. Participants were recruited from 31 provinces in the Mainland of China (n=21,582). Dual use was defined as self-reported ever use of both cigarettes and e-cigarettes. Multivariate logistic regression models with weights (accounting for study design, non-response rate and post hoc stratification) were used to identify the associated factors of dual use, shown in adjusted odds ratios (aOR) and 95% confidence intervals (CI). RESULTS: The prevalence of lifetime dual use of cigarettes and e-cigarettes was 0.82% in China, 2.95% among those who ever smoked, and 3.01% among those who currently smoked. The dual use was consistently more prevalent in urban areas than rural areas and decreased with age. In the adjusted logistic model, dual use was associated with younger age, living in urban areas, single status, high educational level, high income, poor self-reported health status, nicotine dependence, and other smoking-related factors. Withdrawal symptoms were more prevalent among those who used both cigarettes and e-cigarettes compared with those who exclusively smoked cigarettes, including the urge to smoke, hard to concentrate, quick temper, increased appetite, weight gain, involuntary hand tremor, and sleepiness (P<0.05). CONCLUSION: Although the prevalence of lifetime dual use is low, the absolute number of affected individuals in China is substantial. Our study identified key risk factors associated with lifetime dual use, providing critical evidence to inform targeted interventions for at-risk populations and guide the development of tailored tobacco control strategies.

BACKGROUND AND OBJECTIVES:Emerging evidence suggests that the nicotine metabolite ratio (NMR) may influence the efficacy of smoking cessation, yet its role across pharmacotherapies remains unclear. This study aims to investigate how NMR affects cessation outcomes under different medications to guide personalized treatment. METHODS:We searched PubMed, Medline, EMBASE, and the Cochrane Central Register of Controlled Trials (inception to September 30, 2024) for randomized controlled trials on pharmacotherapy for smoking cessation with NMR data. Data were synthesized using random-effects models, with heterogeneity assessment. The primary outcome was verified smoking cessation rate at the end of treatment or the closest time-point. RESULTS:Eleven RCTs with accessible full text were included in the qualitative analyses and nine were included in the quantitative synthesis. For non-titratable nicotine replacement therapy (NRT), normal/fast metabolizers demonstrated lower odds of smoking cessation than slow metabolizers (Odds Ratio, OR=0.81, 95% confidence interval, CI=0.68-0.96; 5 studies, I²=62.5%). No significant associations were shown between normal/fast and slow metabolizers using titratable NRT (OR=1.04, 95% CI=0.95-1.14; 2 studies, I²=0%), bupropion (OR=0.67, 95% CI=0.38-1.16; 2 studies, I²=51.4%), or varenicline (OR=1.17, 95% CI=0.79-1.74; 4 studies, I²=59.8%). CONCLUSION:Current evidence demonstrates that NMR moderates' treatment efficacy among those who smoke using non-titratable NRT, with slow metabolizers achieving significantly better cessation outcomes than normal/fast metabolizers. Substantial further research is needed to determine optimal medication hierarchies across metabolic profiles.

AIMS:To estimate the projected cost-effectiveness of NMR-guided metabolism-informed care (MIC) compared with standard care (SC) for smoking cessation in China. MATERIALS AND METHODS:A 24-week decision tree was linked to an annual semi-Markov cohort model that followed individuals from age 45 to age 100. Clinical inputs were informed by the China National Tobacco Cessation Cohort Study. Stabilized inverse probability of treatment weights were estimated using a multinomial propensity-score model, trimmed at the 1st and 99th percentiles, and analyzed using robust sandwich variance estimators. Under MIC, fast metabolizers (NMR ≥ 0.31) received varenicline, while slow metabolizers (NMR < 0.31) received either nicotine replacement therapy (NRT) or bupropion. Costs were expressed in 2023 Chinese yuan (CNY), and costs and health outcomes were discounted at 5% annually. RESULTS:Over the lifetime model horizon, SC generated 13.125 QALYs per person at a total cost of CNY 40,832.29. Both MIC medication-cost scenarios generated an additional 0.003 QALYs. MIC-Bupropion cost CNY 41,033.81 and yielded an ICER of CNY 67,930.00 per QALY gained versus SC. The corresponding deterministic INMB versus SC was CNY 63.57 at the primary threshold. In the fully incremental analysis, MIC-NRT was strictly dominated by MIC-Bupropion. At CNY 89,358.00 per QALY, MIC-Bupropion had the highest net monetary benefit in 50.4% of probabilistic simulations. LIMITATIONS:Findings depended on observational clinical inputs, literature-derived long-term parameters, and structural assumptions, and did not fully capture all smoking-related diseases, adherence, adverse effects, or implementation costs. CONCLUSIONS:MIC-Bupropion showed favorable expected economic performance relative to SC, whereas MIC-NRT was strictly dominated. Further comparative-effectiveness, budget-impact, and implementation studies are warranted before routine adoption.

Background:Smokers with similar smoking exposure show markedly different risks of chronic obstructive pulmonary disease (COPD), and it remains unclear whether genetically determined nicotine metabolism, measured by the nicotine metabolite ratio (NMR), is independently associated with COPD beyond smoking exposure. Methods:This study integrated genetic evidence and population-based phenotypic analyses. First, two-sample Mendelian randomization (MR) analyses were conducted using genome-wide association study summary statistics to evaluate the causal effect of the NMR on COPD, with colocalization analyses to assess shared causal genetic variants. Second, phenotypic analyses in the China National Tobacco Cessation Cohort Study were conducted in a cross-sectional setting to compare COPD prevalence across metabolic phenotypes under comparable smoking exposure, with mediation analyses evaluating the contribution of smoking behavior. Results:MR analysis showed a causal association between a higher NMR and increased risk of COPD (OR = 1.06, 95% CI: 1.05-1.08). Colocalization analyses identified shared causal variants. Population-based phenotypic analyses showed that COPD prevalence was consistently higher in normal metabolizers (NMR ≥ 0.31) than slow metabolizers (NMR < 0.31), regardless of smoking exposure strata, and more importantly, remained higher within comparable levels of cumulative smoking. Mediation analysis showed that smoking behavior partially mediated this association (indirect effect β = 0.0049, P < 0.001), accounting for 14.5% of the total effect. Conclusion:Nicotine metabolism, as captured by NMR, is causally associated with COPD susceptibility. These findings suggest that incorporating nicotine metabolism into smoking exposure assessment may have potential value in improving COPD risk stratification.

BACKGROUND:We aimed to estimate the changes in, second hand smoke (SHS) and potential drivers of its health outcome from 1990 to 2021 worldwide. METHODS:The data was derived from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021, which covered 204 countries and territories. We reported SHS changes by sex, year and sociodemographic index (SDI) level (a summary measure that identifies where countries or other geographic areas sit on the spectrum of development) from 1990 to 2021. We analyzed the risk-outcome pairs among all age groups to estimate disease burden attributable to SHS exposure and also did a decomposition method to attribute changes in all-cause SHS attributable deaths or disability-adjusted life years (DALYs) to population growth, population aging, and mortality change. RESULTS:Worldwide, the age-standardized summary exposure values (SEV) of SHS exposure in 2021 was 30.6% (28.9 to 31.6) for males and 38.0% (35.5 to 39.0) for females, with a percentage change of -0.2 (-0.2 to -0.1) and -0.3 (-0.3 to -0.2), respectively, since 1990. Among the top 10 countries with the highest SEV, there were mainly high-middle SDI countries for male and low-middle SDI and middle SDI countries for female, respectively. Secondly, about 1.29 million deaths (0.68-1.90) and 34.90 million DALYs (17.95-52.21) were attributable to SHS exposure, and about half of them took place in two countries (China and India). Ischemic heart disease (IHD) (29.67%), chronic obstructive pulmonary disease (COPD) (19.04%), and lower respiratory infections (LRIs) (10.87%) were the three leading causes of SHS associated deaths. Lastly, since 2010, the number of SHS related death significantly increased due to population growth and population aging, despite a decrease in mortality attributable to SHS exposure. CONCLUSION:Globally, the age-standardized SEV of SHS exposure decreased from 1990 to 2021. Since 2010, the increased number of deaths attributable to SHS exposure was mainly attributable to population growth and aging.

AIMS:To assess whether combining nicotine replacement therapy (NRT) with varenicline improves long-term smoking cessation rates compared with varenicline or NRT alone. METHOD:Systematic review and meta-analysis of randomized controlled trials (RCTs) or quasi-RCTs, conducted according to PRISMA guidelines. A comprehensive literature search of PubMed, MEDLINE, EMBASE, Web of Science and the Cochrane Central Register of Controlled Trials was conducted through June 2025. The primary outcome was smoking abstinence at the longest follow-up (≥6 months). Secondary outcomes included adverse events (AEs) and serious adverse events (SAEs). Risk ratios (RRs) with 95% confidence intervals (CIs) were pooled using random-effects meta-analyses. The certainty of evidence was assessed using the GRADE approach. Risk of bias was assessed using the Cochrane RoB 2.0 tool. The protocol was pre-registered in the PROSPERO (registration number CRD42024600510). RESULTS:Seven trials including 2631 participants met inclusion criteria. Compared with varenicline alone, combination therapy was associated with statistically significantly higher abstinence rates at the longest follow-up (RR = 1.33, 95% CI = 1.04-1.69; 5 studies; I2 = 51%). A sensitivity analysis including trials with ≥3 months of follow-up yielded similar results (RR = 1.31, 95% CI = 1.06-1.62; 6 studies). However, when excluding the trial at high risk of bias, the result was not statistically significant (RR = 1.26, 95% CI = 0.94-1.68). Compared with NRT alone, only one RCT was included, and the effect of combination therapy on abstinence was not statistically significant (RR = 0.94, 95% CI = 0.51-1.72). AEs were more common with combination therapy compared with varenicline alone (RR = 1.11, 95% CI = 1.02-1.20). Specifically, skin reactions were significantly increased with NRT patch plus varenicline (RR = 1.67; 95% CI = 1.29-2.16). Compared with NRT alone, combination therapy was associated with increased AEs (RR = 1.23; 95% CI = 1.07-1.41). SAEs were infrequent and generally unrelated to treatment. CONCLUSIONS:Low-certainty evidence indicates that combining varenicline with nicotine replacement therapy may improve long-term smoking cessation rates compared with varenicline alone and is generally well tolerated.

Background: Cigar smoking poses significant public health challenges due to its rising prevalence and associated health risks. However, research on cigar use in China remains limited. This study investigates the prevalence, demographic characteristics, and key factors associated with cigar use among Chinese adults. Methods: We analyzed data from the 2018–2019 China Health Literacy Survey, including 86,701 participants aged 20–69 years. Multistage stratified sampling was employed, and logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for factors associated with cigar use. Weighted data were applied to ensure national representation. Results: Of the 86,701 respondents, 1025 participants reported having used cigars, including 248 exclusive cigar users and 777 dual users of cigars and other tobacco products. Cigar use was significantly higher among men (1.93%) than women (0.05%). Most users were aged 50–59, with a mean age of 49.3 years. Factors associated with cigar use among men included higher education (for college and higher, OR: 1.81; 95% CI: 1.42–2.30), lower household income (for income < 20,000, OR: 1.02; 95% CI: 1.08–1.53), poor self-reported health (OR: 1.45; 95% CI: 1.15–1.83), and severe nicotine dependence (FTND ≥ 7 points, OR: 2.09, 95% CI: 1.67–2.61). Cigar use prevalence showed notable regional variation, with the highest rates observed in northern and eastern provinces. Interpretation: The estimated number of cigar users in China is approximately 10.46 million. Male cigar users often represent a unique demographic: “knowledgeable but economically marginalized” individuals, characterized by higher education but lower economic status. Tailored tobacco control measures addressing regional disparities, socioeconomic factors, and marketing-driven misconceptions about cigars are essential to reduce public health impacts.

BACKGROUND:The comparative efficacy of endoscopic versus microscopic transsphenoidal surgery for patients with pituitary adenoma (PA) remains controversial. Previous retrospective studies have often been limited by inconsistencies in baseline characteristics of patients, which may affect the validity of the comparisons. This study aimed to evaluate the trend in the proportion of transsphenoidal endoscopic and microscopic surgeries in China and compare outcomes in comparable patients. MATERIALS AND METHODS:The National Brain Tumor Registry of China (NBTRC) database was queried to extract PA patients (2011-2021) for trend analysis. Stratified sampling was performed, and a 1:1 propensity score matching (PSM) was used to balance the patients' baseline characteristics. Postoperative outcomes, complications, and prognosis were compared. RESULTS:Among the nationwide 17 012 PA patients, there was a gradual increase in the proportion of endoscopic surgeries (annual percent change, 11.89%). Among the 1863 stratified patients, those who underwent endoscopic surgery had a higher preoperative recurrence rate and higher Knosp and Hardy grades ( P < 0.05). Endoscopic surgery showed a similar gross total resection (GTR) rate to microscopy (55.6% vs. 54.9%, P = 0.886) in the real-world cohort and a higher GTR rate (59.5% vs. 54.3%, P = 0.037) in the PSM cohort. After PSM, there was no significant difference in cerebrospinal fluid leak and secondary surgery ( P > 0.05); endoscopic surgery showed more bleeding, longer surgical time, shorter hospital stay, and higher costs (all P < 0.001) compared to microscopic surgery. The risk of postoperative progression was similar between endoscopic and microscopic surgeries for comparable PA patients ( P = 0.45). CONCLUSION:Endoscopic transsphenoidal surgery is increasingly adopted in China, demonstrating a higher GTR rate than microscopic transsphenoidal surgery in PA patients with similar characteristics, without increasing severe complication rates. The risk of postoperative progression was similar between the two techniques.

BACKGROUND:Cigarette smoking has been reported to be associated with SARS-CoV-2 negative conversion, while little is known about the effect of its dual use with e-cigarettes. This study aimed to investigate whether tobacco product use patterns including e-cigarette use were linked with delayed negative conversion of SARS-CoV-2. METHODS:An online national survey was conducted from January 28 through February 21, 2023, targeting a community-based population in mainland of China after peak waves of the coronavirus disease 2019 (COVID-19). Participants were followed from the onset of COVID-19 symptoms until the negative conversion day or the day of answering the questionnaire as the endpoint of the study. Multi-variable adjusted Cox proportional hazard models were used to compare the negative conversion time of SARS-CoV-2 across different cigarette and e-cigarette use patterns. RESULTS:A total of 66,537 participants infected with COVID-19 were enrolled and 13,294 were included in the analyses. During the median duration of 7 days (interquartile range 5 to 10 days), a total of 11,587 (87.2%) had a negative conversion. Compared with never users, current exclusive smokers (multi-variable adjusted HR 0.59, 95% CI 0.48-0.71), current dual users (HR 0.31, 95% CI 0.22-0.44), and previous smokers (HR 0.56, 95% CI 0.37-0.83) took longer to turn negative after 10 days of follow-up. CONCLUSIONS:Both current exclusive cigarette use and dual use of cigarettes and e-cigarettes were associated with the delayed negative conversion of SARS-CoV-2, which strengthens the importance of smoking and vaping cessation messaging and community-based tobacco control strategies during pandemics like COVID-19 next time.

Chronic obstructive pulmonary disease (COPD) is a complex and heterogeneous respiratory disorder that arises from interactions between genetic susceptibility and environmental exposures, with cigarette smoking being the primary modifiable risk factor. Cigarette smoke reprograms pulmonary glucose metabolism, a process recognized as an early molecular event driving disease progression. Prolonged exposure is associated with enhanced glycolysis, suppression of the tricarboxylic acid cycle and oxidative phosphorylation, mitochondrial dysfunction, and excessive production of mitochondrial reactive oxygen species. These metabolic disturbances converge to form a pathological axis linking metabolism, inflammation, and immunity, leading to immune dysregulation, chronic airway inflammation, and tissue remodeling. This review summarizes the characteristics and molecular mechanisms of cigarette smoke-induced glucose metabolic reprogramming in COPD while highlighting the therapeutic potential of targeting glucose metabolism. Particular emphasis is placed on comprehensive strategies aimed at restoring metabolic homeostasis. A deeper understanding of glucose metabolic reprogramming in COPD associated with smoking may provide novel insights into disease pathogenesis and contribute to the development of individualized therapies. Nevertheless, clinical evidence remains limited, underscoring the need for translational studies targeting glucose metabolism in COPD.

INTRODUCTION:Smoking has been identified as a potential risk factor for adverse COVID-19 outcomes. This study aimed to investigate the association between long-term smoking cessation and COVID-19 outcomes. METHODS:In this nationwide, cross-sectional online survey conducted in China (January-February 2023), 22709 adults with COVID-19, confirmed by nucleic acid amplification test (NAAT) or SARS-CoV-2 antigen testing, were included. Smoking status was self-reported and classified as never smokers, long-term ex-smokers (≥10 years), ex-smokers (<10 years), and current smokers. COVID-19 outcomes, including pneumonia, hospitalization, and severe COVID-19, were compared across these groups. Logistic regression models were used to adjust for potential confounders. Sensitivity analyses included all self-reported cases irrespective of test confirmation. RESULTS:Among 22709 COVID-19-positive participants, current smokers and ex-smokers <10 years exhibited significantly higher proportion of pneumonia, hospitalization, and severe COVID-19 than never smokers. Current smokers (AOR=3.18; 95% CI: 2.90-3.48) and ex-smokers quit <10 years (AOR=3.48; 95% CI: 2.96-4.09) had increased odds of pneumonia, whereas long-term ex-smokers showed no elevated risk (AOR=1.12; 95% CI: 0.45-2.41). These associations were consistent in sensitivity analyses. Other factors significantly associated with pneumonia included sex, education level, residence, obesity, income, and chronic conditions. CONCLUSIONS:Long-term smoking cessation was not associated with an elevated risk of COVID-19-related pneumonia compared to never smokers, whereas ex-smokers (<10 years) and current smokers remained high-risk groups. These findings support the potential benefits of sustained cessation, although further longitudinal studies are needed to confirm and extend these findings.

Objective: To identify factors influencing the intention to quit (ItQ) among Chinese who smoke, focusing on 10th Revision of the International Classification of Diseases (ICD-10) Nicotine dependence. Additionally, to estimate the number of individuals with ItQ, supporting optimal allocation of cessation resources. Methods: This study used data from the 2018 China Health Literacy Survey, a nationally representative crosssectional study with 20,288 participants who smoke currently aged 20-69 years. The ItQ proportions were estimated overall and by subgroup. Logistic regression was employed to estimate ORs and 95 % CIs for ItQ. The number of people who smoke with ItQ was estimated based on the census data. Results: In China, 41.34 % of individuals who smoke had ItQ, higher in females (44.89 %) than males (41.34 %). Provincial proportions ranged from 23.53 % to 63.56 %. ItQ was significantly associated with smoking characteristics, including occasional smoking (OR = 2.08, 95 % CI = 1.88-2.20), fewer pack-years (OR = 0.70, 95 % CI = 0.68-0.73), older smoking initiation age (OR = 1.22, 95% CI = 1.18-1.27), and ICD-10 Nicotine dependence (OR = 1.12, 95 % CI = 1.06-1.19), as well as age, sex, socioeconomic factors, and health status. Withdrawal symptoms were positively associated with ItQ in individuals who smoke without ICD-10 Nicotine dependence but negatively in those with ICD-10 Nicotine dependence. An estimated 100.3 million adults aged 20-69 in China have ItQ, with 52.14 million suffering from ICD-10 Nicotine dependence. Conclusions: The intention to quit smoking among Chinese who smoke is low and varies by ICD-10 Nicotine dependence and region, underscoring the need for targeted smoking cessation interventions across diverse smoking populations.

The impact of e-cigarettes on COVID-19 remains unclear. This study aims to assess the relationship between e-cigarette use and COVID-19 diagnosis and other related outcomes. This systematic review and meta-analysis searched studies from 2019 to April 2nd, 2024, in Medline (via OVID), EMBASE, Scopus and the Cochrane Central Register of Controlled Trials for eligible observational studies. Among the initially identified 1116 items, a total of 20 studies met the inclusion criteria. The meta-analysis revealed that e-cigarette use was significantly associated with higher odds of COVID-19 diagnosis (N = 14, adjusted odds ratio, OR 1.25, 95

Background:Social media platforms have become influential spaces for disseminating information about electronic cigarettes (e-cigarettes). Concerns persist about the spread of misleading content, particularly among social media vulnerable groups. Xiaohongshu (RedNote), widely used by Chinese youth, plays a growing role in shaping e-cigarette perceptions. Understanding the narratives circulating on this platform is essential for identifying misinformation, assessing public perception, and guiding future health communication strategies. Objective:This study aimed to analyze the content, topics, user engagement, and sentiment trends of e-cigarette-related posts on Xiaohongshu and to assess the factors that influence engagement. Methods:E-cigarette-related posts published on Xiaohongshu between January 2020 and November 2024 were collected using web scraping, based on a predefined keyword list and a time-stratified random sampling strategy. Posts were categorized into 4 themes: advertising promotion, health hazards, usage interaction, and others. High-frequency keywords were extracted, and representative quotes were included to illustrate user perspectives across each category. Sentiment analysis was performed on posts in the usage interaction category to assess public attitudes. We defined 4 sentiment categories: positive, negative, neutral, and mixed. Logistic regression was conducted to explore the effects of post type, content length, and thematic classification on user engagement metrics such as likes, saves, and comments. Results:A total of 1729 posts were included and analyzed. Usage interaction posts were the most common (681/1729, 39.39%), with keywords such as "experience," "regulations," and "quit smoking" dominating this category. Advertising promotion posts (512/1729, 29.61%) frequently used terms like "flavor," "fashion," and "design" to attract younger users. Health hazards posts (311/1729, 17.99%) highlighted risks with keywords like "nicotine," "addiction," and "secondhand smoke," while others included policy and industry updates. Representative quotes highlighted typical concerns about aesthetics, health risks, and cessation struggles. Health hazards posts garnered the highest engagement in terms of likes and saves, despite their limited presence (odds ratio [OR] 1.498, 95% CI 1.099-2.042, P=.01). Video posts significantly outperformed text-image posts in generating comments (OR 2.624, 95% CI 2.017-3.439, P<.001). Sentiment analysis of the usage interaction posts (n=681) revealed that 53.45% (364/681) were positive, highlighting reduced harm, convenience, or flavor preferences. Negative sentiment was observed in 33.48% (228/681) of posts, often expressing concerns about addiction and health risks. Mixed sentiments appeared in 6.90% (47/681), acknowledging both pros and cons. In addition, 6.17% (42/681) of posts were classified as neutral without evident emotional tone. Conclusions:The findings underscore the dual role of Xiaohongshu as a platform for both e-cigarette promotion and public discourse. Misleading marketing targeting vulnerable groups, such as adolescents, remains a critical issue. However, the strong user response to health-related content suggests that social media platforms could be leveraged for effective health education. Strengthened regulatory oversight and educational campaigns leveraging engaging content formats are urgently needed to counter misinformation and protect public health.