Table 2_Intranasal insulin and postoperative delirium in adult surgical patients: a meta-analysis and systematic review of randomized controlled trials.docx

IntroductionThe efficacy and safety of intranasal insulin (INI) for preventing postoperative delirium (POD) remain uncertain.
MethodsWe searched PubMed, Web of Science, Cochrane Library, Embase, and registers from inception to July 1, 2025, for randomized controlled trials (RCTs) enrolling adult surgical patients that compared INI with control (saline) investigating the efficacy of INI for POD prevention. The risk of bias was assessed using the revised Cochrane Risk of Bias tool (RoB 2), and the certainty of evidence was evaluated with the GRADE framework. Primary and secondary outcomes were POD incidence and a comprehensive set of secondary measures (including cognitive scores, hypoglycemia rates, pain scores, and inflammatory markers), respectively.
ResultsA meta-analysis of 7 randomized trials (n = 765) showed that INI significantly reduced the incidence of POD within 3 days postoperatively (RR = 0.35; 95% CI: 0.26–0.46; P < 0.001; I2 = 0%) and improved cognitive recovery (MMSE mean difference = 0.99; 95% CI: 0.52–1.47; P < 0.001; I2 = 1.7%). INI also reduced early postoperative interleukin-6 (IL-6) levels without affecting the incidence of hypoglycemia or pain scores.
ConclusionINI may protect perioperative cognitive function, reduce POD incidence within 3 days postoperatively, and alleviate postoperative inflammation without increasing hypoglycemia risk. However, larger-scale, randomized, multicenter trials are needed to confirm clinical efficacy and establish optimal protocols.
Clinical trial registrationThe protocol for this meta-analysis is available in PROSPERO (CRD42024614995).

引言 鼻内胰岛素（intranasal insulin, INI）用于预防术后谵妄（postoperative delirium, POD）的有效性与安全性目前仍不明确。
方法 本研究检索了PubMed、Web of Science、Cochrane图书馆、Embase及各临床试验注册库，检索时限设置为从建库至2025年7月1日，纳入比较鼻内胰岛素与对照（生理盐水）用于预防术后谵妄的随机对照试验（randomized controlled trials, RCTs），研究对象为成年手术患者。采用修订版Cochrane偏倚风险评估工具（RoB 2）评价偏倚风险，使用GRADE框架评估证据质量。主要结局指标为术后谵妄发生率，次要结局指标则涵盖一系列综合评估项：认知评分、低血糖发生率、疼痛评分及炎症标志物水平。
结果 针对7项随机试验（共纳入765名受试者）的荟萃分析显示，鼻内胰岛素可显著降低术后3天内的术后谵妄发生率（相对危险度RR=0.35；95%置信区间CI：0.26~0.46；P<0.001；I²=0%），并改善认知恢复情况（简易精神状态检查表（Mini-Mental State Examination, MMSE）均数差=0.99；95%CI：0.52~1.47；P<0.001；I²=1.7%）。此外，鼻内胰岛素可降低术后早期白细胞介素-6（interleukin-6, IL-6）水平，且不影响低血糖发生率与疼痛评分。
结论 鼻内胰岛素可保护围手术期认知功能，降低术后3天内的术后谵妄发生率，减轻术后炎症反应，且不会增加低血糖风险。但未来仍需开展大样本、多中心随机对照试验，以验证其临床有效性并确立最优应用方案。
临床试验注册 本荟萃分析的研究方案已在PROSPERO平台注册（注册号：CRD42024614995）。