基于IPTW法筛选高脂血症人群的差异肠道菌群

目的:研究高脂血症患者与非高脂血症人群肠道菌群的差异。方法:采用Illumina HiSeq二代测序技术分析肠道菌群组成和丰度,利用逆处理概率加权法(IPTW)校正混杂因素,通过QIIME2 ANCOM筛选高脂血症的差异菌群,运用R Tax4Fun包进行功能预测。结果:高脂血症组和非高脂血症组共有7个差异扩增序列变体(ASVs)(ASV_232、ASV_63、ASV_173、ASV_46、ASV_393、ASV_283、ASV_41);甘油三酯组和非甘油三酯组(TG组与非TG组)只有1个差异ASV_(ASV_422);高密度脂蛋白胆固醇组与非高密度脂蛋白胆固醇组(HDL-C组和非HDL-C组)共有18个差异ASVs(ASV_9、ASV_15、ASV_28、ASV_36、ASV_50、ASV_56、ASV_80、ASV_99、ASV_153、ASV_45、ASV_636、ASV_243、ASV_109、ASV_516、ASV_13、ASV_74、ASV_96、ASV_259)。功能预测结果显示:高脂血症组与非高脂血症组样本菌群功能组成高度相似,没有发现显著差异,大多数功能基因与能量代谢有关。结论:高脂血症患者与非高脂血症人群的差异肠道菌群为毛螺菌科、疣微菌科,双歧杆菌属、粪杆菌属、拟杆菌属、瘤胃菌属_UCG-013、Agathobacter、Subdoligranulum、Lachnoclostridium、Lachnospiraceae_UCG-010属,该结果说明碳水化合物代谢和氨基酸代谢所占比例较大。

Net Effect of Short-Term Smoking Cessation on Mental Health Changes:Inverse Probability of Treatment Weighting and Difference-in-Differences Method

Background:In response to the need for research clearly demonstrating the net effect of smoking cessation on mental health status,considering the causal relationship between smoking cessation and changes in mental health status,this study was undertaken.Thus,this study aimed to examine the net effect of short-term smoking cessation on five specific mental health metrics and the overall mental health status score.Methods:We used data from the first wave of the Korean Health Panel(KHP)Survey(2011–2013,2016–2018)and focused on men aged 19 years and older,to explore the effects of smoking cessation.We compared mental health status before and after cessation among current non-smokers who had quit smoking and continuous smokers.We ensured homogeneity between the two groups via inverse probability of treatment weighting(IPTW)and employed a difference-in-differences(DID)analysis to assess changes in mental health status.This study controlled for factors that could influence mental health and explored the net effect of short-term smoking cessation through difference-in-differences model using multiple regression analysis.Results:The results showed that short-term smoking cessation significantly alleviated mental and physical stress(p<0.1),reduced experiences of frustration(p<0.01),and improved the overall mental health status score(p<0.1).Conclusion:Thus,these results highlight a meaningful link between positive health behavior changes,such as smoking cessation,and enhanced mental health.Moreover,the application of temporal variables further improved the understanding of the causal relationship between health behaviors and mental health.

边缘结构模型在职业暴露跟踪研究中的应用理论探讨

为解决在职业暴露跟踪调查及重复测量研究中,健康工人效应会使研究结果出现偏差的问题,采用新型的边缘结构模型(MSM)对相关数据进行处理。通过构造与事实相反的虚构样本,同时处理不同情况下的数据删失问题,以寻找跟踪调查的中间结果作为时变混杂变量,进而计算稳定反概率处理权重(IPTW)以修正健康工人效应造成的统计结果偏差,并用MSM来处理实际样本数据。结果表明:MSM可以通过使用稳定IPTW在一定程度上减少职业暴露研究数据分析过程中健康工人效应对研究的影响,比以往的数据分析方法更能准确地反映重复测量跟踪调查研究中职业暴露水平与职业危害间的关系。

基于倾向性评分逆概率加权法胃癌患者疗效评价

目的基于倾向性评分逆概率加权法(IPTW)评价手术、放疗和联合治疗3种方式治疗胃癌患者的疗效,为胃癌的治疗提供参考依据。方法收集2004年1月—2013年12月美国国家癌症研究所监测、流行病学与预后项目(SEER)数据库中经胃镜病理诊断确诊的7005例胃癌患者数据,其中接受手术治疗者3983例、接受放疗者795例、接受联合治疗者2227例;采用倾向性评分IPTW法以生存时间和结局为效应指标,分析不同的治疗方法对胃癌患者生存率的影响。结果手术组、放疗组和联合治疗组胃癌患者倾向性评分IPTW法加权前中位生存期分别为30、9和38个月,加权后分别为25、11和38个月,加权前、后3组胃癌患者生存曲线间差异均有统计学意义(均P<0.001),联合治疗组患者加权前、后的预后均优于手术组和放疗组患者;加权后大部分基线特征绝对标准化平均差异(ASMD)减小,且均<0.2,3组患者均衡效果较好;在控制了性别、年龄、种族、婚姻状况、肿瘤大小、病理分化、肿瘤分期、T分期、N分期和远处转移情况等混杂因素后,多因素Cox回归分析结果显示,与手术组胃癌患者相比,放疗组胃癌患者的预后较差(HR=2.044,95%CI=1.770~2.361),联合治疗组胃癌患者的预后较好(HR=0.630,95%CI=0.573~0.694)。结论联合治疗方法疗效优于手术和放疗治疗方法。