Discrete event simulation (DES) model is based on individual data, by which discrete events over time are simulated to reflect disease progression. The effects of individual characteristics on disease progression could be considered in the DES model. Moreover, unlike state-transition models, DES model without setting of fixed cycle can contribute to more accurate estimation of event time, especially in the evaluation of the long-term effectiveness of screening strategies for complex diseases in which time dimension needs to be considered. This article introduces the general principles, construction steps, analytic methods and other relevant issues of the DES model. Based on a research case of estimating the cost-effectiveness of screening for abdominal aortic aneurysms in women aged 65 years and above in the United Kingdom, key points in applications of the DES model in analysis on effectiveness of complex disease screening are discussed in detail, including model construction and analysis and interpretation of the results. DES model can predict occurring time of discrete events accurately by establishing the distribution function of their occurring time and is increasingly used to evaluate the screening strategies for complex diseases in which time dimension needs to be considered. In the construction of DES model, it is necessary to pay close attention to the clear presentation of model structure and simulation process and follow the relevant reporting specification to conduct cost-effectiveness analysis to ensure the transparency and repeatability of the research.
Humans ; Female ; Cost-Benefit Analysis ; Cost-Effectiveness Analysis ; Disease Progression

High density lipoprotein (HDL) is an important biochemical index of clinical cardiovascular disease. Many new studies have demonstrated abnormalities of plasma HDL subfractions in patients with this disease,and their clinical significance is greater than the overall abnormalities of HDL. Therefore,the HDL subfraction as an important factor in cardiovascular disease has attracted extensive research and attention. This article summarizes current research on HDL subfractions,their measurements and their relationships with atherosclerosis and coronary artery disease.
Humans ; Cardiovascular Diseases ; Clinical Relevance ; Cholesterol, HDL ; Lipoproteins, HDL ; Coronary Artery Disease

Objective: To understand HIV self-testing and related factors in men who have sex with men (MSM) in Shijiazhuang. Methods: From August to September 2020, convenient sampling was used to recruit MSM in Shijiazhuang. Online questionnaires were used to collect information about their demographic characteristics, sexual behaviors and HIV self-testing. logistic regression model was used to analyze the related factors associated with HIV self-testing. Results: In the 304 MSM respondents, 52.3% (159/304) had HIV self-testing in the past 6 months, and 95.0% (151/159) used fingertip blood HIV detection reagent. Self-purchase was the main way to obtain HIV testing reagents (45.9%, 73/159), followed by supply from MSM social organization (44.7%, 71/159). The reasons for having HIV self-testing were non-specific testing time (67.9%, 108/159) and privacy protection (62.9%,100/159), the reasons for having no HIV self-testing included inability of using (32.4%, 47/145), being unaware of HIV self-testing reagent (24.1%, 35/145), and worry about inaccurate self-testing results (19.3%, 28/145). Multivariate logistic regression analysis showed that being 18-29 years old (aOR=2.68, 95%CI: 1.20-5.94), obtaining free HIV self-testing kits in recent 6 months (aOR=8.61, 95%CI: 4.09-18.11) and making friends through Internet and social software (aOR=2.68, 95%CI: 1.48-4.88) were positive factors for having HIV self-testing. Conclusion: HIV self-testing is a more flexible and convenient way to detect HIV in MSM, and the promotion of HIV self-testing in MSM should be strengthened to further increase the HIV detection rate in this population.
Male ; Humans ; Adolescent ; Young Adult ; Adult ; Homosexuality, Male ; Self-Testing ; Sexual and Gender Minorities ; HIV Testing ; Sexual Behavior

Child ; Humans ; Class I Phosphatidylinositol 3-Kinases/genetics* ; Mutation ; Neoplasms, Germ Cell and Embryonal/genetics*

OBJECTIVE: To compare the expected population impact of benefit and risk of aspirin treatment strategies for the primary prevention of cardiovascular diseases recommended by different guidelines in the Chinese Electronic Health Records Research in Yinzhou (CHERRY) study. METHODS: A decision-analytic Markov model was used to simulate and compare different strategies of aspirin treatment, including: Strategy ①: Aspirin treatment for Chinese adults aged 40-69 years with a high 10-year cardiovascular risk, recommended by the 2020 Chinese Guideline on the Primary Prevention of Cardiovascular Diseases; Strategy ②: Aspirin treatment for Chinese adults aged 40-59 years with a high 10-year cardiovascular risk, recommended by the 2022 United States Preventive Services Task Force Recommendation Statement on Aspirin Use to Prevent Cardiovascular Disease; Strategy ③: Aspirin treatment for Chinese adults aged 40-69 years with a high 10-year cardiovascular risk and blood pressure well-controlled (< 150/90 mmHg), recommended by the 2019 Guideline on the Assessment and Management of Cardio-vascular Risk in China. The high 10-year cardiovascular risk was defined as the 10-year predicted risk over 10% based on the 2019 World Health Organization non-laboratory model. The Markov model simulated different strategies for ten years (cycles) with parameters mainly from the CHERRY study or published literature. Quality-adjusted life year (QALY) and the number needed to treat (NNT) for each ischemic event (including myocardial infarction and ischemic stroke) were calculated to assess the effectiveness of the different strategies. The number needed to harm (NNH) for each bleeding event (including hemorrhagic stroke and gastrointestinal bleeding) was calculated to assess the safety. The NNT for each net benefit (i.e., the difference of the number of ischemic events could be prevented and the number of bleeding events would be added) was also calculated. One-way sensitivity analysis on the uncertainty of the incidence rate of cardiovascular diseases and probabilistic sensitivity analysis on the uncertainty of hazard ratios of interventions were conducted. RESULTS: A total of 212 153 Chinese adults, were included in this study. The number of people who were recommended for aspirin treatment Strategies ①-③ was 34 235, 2 813, and 25 111, respectively. The Strategy ③ could gain the most QALY of 403 [95% uncertainty interval (UI): 222-511] years. Compared with Strategy ①, Strategy ③ had similar efficiency but better safety, with the extra NNT of 4 (95%UI: 3-4) and NNH of 39 (95%UI: 19-132). The NNT per net benefit was 131 (95%UI: 102-239) for Strategy ①, 256 (95%UI: 181-737) for Strategy ②, and 132 (95%UI: 104-232) for Strategy ③, making Strategy ③ the most favorable option with a better QALY and safety, along with similar efficiency in terms of net benefit. The results were consistent in the sensitivity analyses. CONCLUSION The aspirin treatment strategies recommended by the updated guidelines on the primary prevention of cardiovascular diseases showed a net benefit for high-risk Chinese adults from developed areas. However, to balance effectiveness and safety, aspirin is suggested to be used for primary prevention of cardiovascular diseases with consideration for blood pressure control, resulting in better intervention efficiency.
Adult ; Humans ; Aspirin/therapeutic use* ; Cardiovascular Diseases/epidemiology* ; Gastrointestinal Hemorrhage ; Myocardial Infarction/prevention & control* ; Primary Prevention/methods* ; Middle Aged ; Aged

High density lipoprotein (HDL) is an important biochemical index of clinical cardiovascular disease. Many new studies have demonstrated abnormalities of plasma HDL subfractions in patients with this disease,and their clinical significance is greater than the overall abnormalities of HDL. Therefore,the HDL subfraction as an important factor in cardiovascular disease has attracted extensive research and attention. This article summarizes current research on HDL subfractions,their measurements and their relationships with atherosclerosis and coronary artery disease.
Humans ; Cardiovascular Diseases ; Clinical Relevance ; Cholesterol, HDL ; Lipoproteins, HDL ; Coronary Artery Disease

OBJECTIVE: To evaluate the effectiveness of statin treatment strategies based on risk assessment for the primary prevention of cardiovascular diseases by the Western guidelines in a community-based Chinese population from economically developed areas using data from the Chinese electronic health records research in Yinzhou (CHERRY) study. METHODS: A Markov model was used to evaluate the effectiveness of the following statin treatment strategies, including: (1) usual care without cardiovascular risk assessment(Strategy 0); (2) using the World Health Organization (WHO) non-laboratory-based risk charts with statin treatment for high-risk group (risk ≥ 20%) (Strategy 1); (3) using the WHO laboratory-based risk charts with statin treatment for high-risk group (risk ≥ 20%) (Strategy 2); and (4) using the Prediction for Atherosclerotic cardiovascular disease Risk in China (China-PAR) model with statin treatment for high-risk group (risk ≥ 10%, Strategy 3). According to the guidelines, adults in the medium-risk group received lifestyle intervention, and adults in the high-risk group received life-style intervention and statin treatment under these strategies. The Markov model simulated different strategies for ten years (cycles) using parameters from the CHERRY study, published data, meta-analyses and systematic reviews for Chinese. The number of cardiovascular events or deaths, as well as the number need to treat (NNT) with statin per cardiovascular event or death prevented, were calculated to compare the effectiveness of different strategies. One-way sensitivity analysis on the uncertainty of incidence rate of cardiovascular diseases, and probabilistic sensitivity analysis on the uncertainty of hazard ratios of interventions were conducted. RESULTS: Totally 225 811 Chinese adults aged 40-79 years without cardiovascular diseases at baseline were enrolled. In contrast to the usual care without risk assessment-based statin treatment strategy, Strategy 1 using the WHO non-laboratory-based risk charts could prevent 3 482 [95% uncertainty interval (UI): 2 110-4 661] cardiovascular events, Strategy 2 using the WHO laboratory-based risk charts could prevent 3 685 (95%UI: 2 255-4 912) events, and Strategy 3 using the China-PAR model could prevent 3 895 (95%UI: 2 396-5 181) events. NNTs with statin per cardiovascular event prevented were 22 (95%UI: 14-54), 21 (95%UI: 14-52), and 27 (95%UI: 17-67), respectively. Strategy 3 could prevent more cardiovascular events, while Strategies 1 and 2 required fewer numbers need to treat with statin per cardiovascular event prevented. The results were consistent in the sensitivity analyses. CONCLUSION The statin treatment strategies based on risk assessment for the primary prevention of cardiovascular diseases recommended by the Western guidelines could achieve substantive health benefits in adults from developed areas of China. Using the China-PAR model for cardiovascular risk assessment could prevent more cardiovascular diseases while using the WHO risk charts seems more efficient.
Adult ; Cardiovascular Diseases/prevention & control* ; China/epidemiology* ; Cost-Benefit Analysis ; Humans ; Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use* ; Primary Prevention

OBJECTIVE: To evaluate the effectiveness of different screening strategies for type 2 diabetes to prevent cardiovascular disease in a community-based Chinese population from economically developed areas based on the Chinese electronic health records research in Yinzhou (CHERRY) study. METHODS: A Markov model was used to simulate different systematic diabetes screening strategies, including: (1) screening among Chinese adults aged 40-70 years recommended by the 2020 Chinese Guideline for the prevention and Treatment of Type 2 Diabetes (Strategy 1); (2) screening among Chinese adults aged 35 to 70 years recommended by the 2022 American Diabetes Association Standard of Medical Care in Diabetes (Strategy 2); and (3) screening among Chinese adults aged 35-70 years with overweight or obesity recommended by the 2021 United States Preventive Services Task Force Recommendation Statement on Screening for Prediabetes and Type 2 Diabetes (Strategy 3). According to the guidelines, individuals who were screened positively (fasting plasma glucose ≥ 7.0 mmol/L) would be introduced to intensive glycemic targets management (glycated hemoglobin < 7.0%).The Markov model simulated different screening scenarios for ten years (cycles) with parameters mainly from the CHERRY study or published literature. Number of cardiovascular disease events or deaths could be prevented and number needed to screen (NNS) were calculated to compare the effectiveness of the different strategies. One-way sensitivity analysis on the sensitivity of screening methods and probabilistic sensitivity analysis on uncertainties of diabetes incidence, the sensitivity of screening methods, and intensive glycemic management effects were conducted. RESULTS: Totally 289 245 Chinese adults aged 35-70 years without cardiovascular diseases or diagnosed diabetes at baseline were enrolled. In terms of the number of cardiovascular disease events could be prevented, Strategy 1 for systematic diabetes screening among the adults aged 35-70 years was 222 (95%UI: 180-264), Strategy 2 for systematic diabetes screening among the adults aged 40-70 years was 227 (95%UI: 185-271), and Strategy 3 for systematic diabetes screening among the adults aged 35-70 years with obesity or overweight (body mass index ≥ 24 kg/m²) was 131 (95%UI: 98-164), compared with opportunistic screening. NNS per cardiovascular disease event for the strategies 1, 2 and 3 were 1 184 (95%UI: 994-1 456), 1 274 (95%UI: 1 067-1 564) and 814 (95%UI: 649-1 091), respectively. Compared with Strategy 1, NNS per cardiovascular disease event for Strategy 2 increased by 90 (95%UI: -197-381) with similar effectiveness of cardiovascular prevention; however, NNS per cardiovascular disease event for Strategy 3 was reduced by 460 (95%UI: 185-724) in contrast to the Strategy 2, suggesting that the Strategy 3 was more efficient. The results were consistent in multiple sensitivity analyses. CONCLUSION Systematic screening for diabetes based on the latest guidelines in economically developed areas of China can reduce cardiovascular events and deaths. However, merely lowering the starting age of screening from 40 to 35 years seems ineffective for preventing cardiovascular disease, while screening strategy for Chinese adults aged 35-70 years with overweight or obesity is recommended to improve efficiency.
Adult ; Cardiovascular Diseases/prevention & control* ; China/epidemiology* ; Cost-Benefit Analysis ; Diabetes Mellitus, Type 2/prevention & control* ; Humans ; Mass Screening/methods* ; Obesity ; Overweight ; United States

Blastocystis hominis is a parasite that parasitizes in the intestines of humans and animals, and is closely related to a variety of gastrointestinal diseases such as abdominal pain and diarrhea. B. hominis is distributed worldwide, and the prevalence of B. hominis infections and dominant subgenotypes vary in countries and in regions from the same country. This paper reviews the global prevalence of B. hominis human infections, its subtypes and geographical distribution, so as to provide insights into the understanding of the global epidemiology of B. hominis and the management of B. hominis infections.

The Solanaceae plants distributed in China belong to 105 species and 35 varietas of 24 genera. Some medicinal plants of Solanaceae are rich in tropane alkaloids(TAs), which have significant pharmacological activities. In this paper, the geographical distribution, chemical components, traditional therapeutic effect, pharmacological activities, and biosynthetic pathways of TAs in Solanaceous plants were summarized. Besides, the phylogeny of medicinal plants belonging to Solanaceae was visualized by network diagram. Fourteen genera of Solanaceae plants in China contain TAs and have medical records. TAs mainly exist in Datura, Anisodus, Atropa, Physochlaina, and Hyoscyamus. The TAs-containing species were mainly concentrated in Southwest China, and the content of TAs was closely related to plant distribution area and altitude. The Solanaceae plants containing TAs mainly have antispasmodic, analgesic, antiasthmatic, and antitussive effects. Modern pharmacological studies have proved the central sedative, pupil dilating, glandular secretion-inhibiting, and anti-asthma activities of TAs. These pharmacological activities provide a reasonable explanation for the traditional therapeutic efficacy of tropane drugs. In this paper, the geographical distribution, chemical components, traditional therapeutic effect, and modern pharmacological activities of TAs-containing species in Solanaceae were analyzed for the first time. Based on these data, the genetic relationship of TAs-containing Solanaceae species was preliminarily discussed, which provided a scientific basis for the basic research on TAs-containing solanaceous species and was of great significance for the development of natural medicinal plant resources containing TAs.
Biosynthetic Pathways ; Phylogeny ; Plants, Medicinal ; Solanaceae/genetics* ; Tropanes