Supplementary Material for: Inflammatory Bowel Disease is Associated with Pericarditis: A Cross-Sectional Study in an NIH-Sponsored, Nationwide Database

Introduction Inflammatory bowel disease (IBD) is a chronic inflammatory condition affecting approximately 2.39 million individuals in the United States. IBD is associated with extraintestinal manifestations (EIMs), among which pericarditis is prominent, comprising 70% of cardiac EIMs. The onset of pericarditis in these patients is primarily attributed to IBD medication-related adverse effects and is predominantly documented through case reports. This highlights the need for an epidemiological study in a large, propensity-matched cohort, given the significant morbidity and mortality of pericarditis. Methods Using the National Institutes of Health’s (NIH) All of Us Research Program, we conducted a cross-sectional study and propensity-matched 5,178 IBD cases to 15,534 controls (1:3). We compared demographics, clinical characteristics, prevalence of autoimmune diseases, and rates of pericarditis. Logistic regressions assessed the association between IBD and pericarditis, adjusting for confounders (p < 0.15), and a sensitivity analysis confirmed the association (p < 0.001). A Kaplan-Meier analysis compared the incidence of pericarditis in various IBD severity cohorts, including mild (n=620) and moderate/severe (n=1,908), stratified by IBD medication exposure. Results Pericarditis was significantly more prevalent in IBD cases (1.3% vs. 0.6%; absolute risk difference (ARD) 0.7%, 95% confidence interval (CI) 0.37%–1.03%), with significant associations in univariable (odds ratio (OR) 2.2, 95% CI 1.6–3.0, p < 0.001) and multivariable analyses (OR 1.9, 95% CI 1.3–2.6, p < 0.001). IBD preceded pericarditis in 65% of cases. There was no difference in pericarditis-free survival between mild and moderate/severe cohorts (p = 0.90). Conclusion This study uniquely provides evidence of a significant association between IBD and pericarditis, establishing pericarditis as a clinically significant EIM in a large, diverse U.S. cohort, independent of disease severity. This highlights the need for heightened screening to enhance pericarditis management and patient outcomes.

引言 炎症性肠病（Inflammatory Bowel Disease, IBD）是一类慢性炎症性疾病，在美国约有239万患者。IBD常伴随肠外表现（Extraintestinal Manifestations, EIMs），其中心包炎（pericarditis）较为突出，占心脏相关肠外表现的70%。此类患者的心包炎发作主要与IBD治疗药物相关不良反应有关，目前相关证据多来自个案报道。鉴于心包炎可导致严重的发病率与死亡率，当前亟需开展基于大样本倾向匹配队列的流行病学研究。
方法 本研究依托美国国立卫生研究院（National Institutes of Health, NIH）的“我们所有人”研究计划（All of Us Research Program），开展了一项横断面研究，按照1:3的比例将5178例IBD患者与15534例对照人群进行倾向得分匹配。研究对比了两组人群的人口学特征、临床特点、自身免疫疾病患病率以及心包炎发生率。采用logistic回归分析评估IBD与心包炎的关联，并对混杂因素进行校正（P<0.15）；敏感性分析验证了该关联（P<0.001）。采用Kaplan-Meier分析对比了不同严重程度分层的IBD队列的心包炎发生率，队列按IBD治疗药物暴露情况划分，其中轻度IBD队列620例，中/重度IBD队列1908例。
结果 IBD患者的心包炎患病率显著高于对照人群（1.3% vs. 0.6%；绝对风险差（Absolute Risk Difference, ARD）为0.7%，95%置信区间（Confidence Interval, CI）为0.37%~1.03%），单因素（比值比（Odds Ratio, OR）=2.2，95%CI：1.6~3.0，P<0.001）与多因素logistic回归分析均显示二者存在显著关联（OR=1.9，95%CI：1.3~2.6，P<0.001）。65%的病例中，IBD发病早于心包炎。轻度与中/重度IBD队列的无心包炎生存率无显著差异（P=0.90）。
结论 本研究首次在大样本、多元化的美国人群队列中证实了IBD与心包炎之间存在显著关联，明确心包炎为具有临床意义的IBD肠外表现，且该关联不受疾病严重程度影响。该研究结果提示，需加强心包炎筛查以优化其诊疗管理，改善患者预后。