Supplementary Material for: Glucocorticoids and Rates of Biphasic Reactions in Patients with Adrenaline-Treated Anaphylaxis: A Propensity Score Matching Analysis

Background: The effectiveness of glucocorticoids in preventing biphasic reactions in patients with anaphylaxis remains controversial. Objective: We evaluated the effects of glucocorticoids on rates of biphasic reactions in hospitalized patients with anaphylaxis treated with adrenaline. Methods: In this retrospective observational study using a national inpatient database in Japan, we identified 31,570 hospitalized patients with anaphylaxis treated with adrenaline on the day of admission. We divided them into two groups: those who were treated with adrenaline plus glucocorticoids and those who received adrenaline only on the day of admission. The primary outcome was the occurrence of a biphasic reaction, defined as requiring two or more ampules of adrenaline within 7 days of admission. We performed a one-to-four propensity score matching analysis to compare the outcomes between the two groups. Results: Of the 31,570 eligible patients, 28,145 (89.2%) were treated with glucocorticoids on the day of admission. The overall percentage of biphasic reactions within 7 days of admission was 11.2%. One-to-four propensity score matching created matched cohorts of 3,425 patients in the control group and 13,700 patients in the glucocorticoid group. After propensity score matching, there were no significant differences in rates of biphasic reactions (10.7% in the glucocorticoids group vs. 10.5% in the control group; odds ratio, 1.03; 95% confidence interval, 0.85–1.24; p = 0.77) between patients with anaphylaxis treated with and without glucocorticoids on the day of admission. Conclusion: Our findings do not support the use of glucocorticoids to prevent biphasic reactions in hospitalized patients with severe anaphylaxis requiring adrenaline.

背景：糖皮质激素用于预防过敏反应（anaphylaxis）患者出现双相反应（biphasic reactions）的有效性仍存在争议。
目的：本研究评估糖皮质激素（glucocorticoids）对接受肾上腺素（adrenaline）治疗的住院过敏反应患者双相反应发生率的影响。
方法：本研究依托日本全国住院患者数据库开展回顾性观察研究，共纳入31570例入院当日接受肾上腺素治疗的住院过敏反应患者。将其分为两组：入院当日接受肾上腺素联合糖皮质激素治疗组，以及仅接受肾上腺素治疗组。本研究的主要结局为双相反应发生情况，定义为入院后7天内需要使用2支及以上肾上腺素安瓿。采用1:4倾向得分匹配（propensity score matching）分析对两组患者的结局进行比较。
结果：在31570例符合纳入标准的患者中，28145例（89.2%）在入院当日接受了糖皮质激素治疗。入院后7天内双相反应的总体发生率为11.2%。经1:4倾向得分匹配后，对照组与糖皮质激素治疗组的匹配队列分别包含3425例和13700例患者。倾向得分匹配后，入院当日接受与未接受糖皮质激素治疗的过敏反应患者，其双相反应发生率无显著差异（糖皮质激素组为10.7%，对照组为10.5%；比值比（odds ratio）为1.03；95%置信区间（95% confidence interval）为0.85~1.24；p=0.77）。
结论：本研究结果不支持对需接受肾上腺素治疗的重症过敏反应住院患者使用糖皮质激素预防双相反应。