Sheffield Teaching Hospitals NHS Foundation Trust and Sheffield University, UK.
University Hospitals Coventry and Warwickshire, UK.
Int J Surg. 2021 Sep;93:106063. doi: 10.1016/j.ijsu.2021.106063. Epub 2021 Aug 16.
Postoperative delirium (POD) is associated with increased mortality, increased length of hospital stays and increased rates and severity of subsequent cognitive decline including dementia. A wide range of risk factors for POD have been suggested in the literature across multiple surgical specialities. However few are validated and no accurate prognostic models exist. We therefore aimed to map the existing evidence regarding risk factors for POD to help guide future research by undertaking an umbrella review of systematic reviews examining risk factors for POD in any context.
We systematically searched multiple medical databases for systematic reviews examining the risk factors for POD in adults undergoing any surgery. We then selected relevant reviews with minimal overlap in primary studies and extracted information about individual risk factors.
Thirty-five relevant reviews were identified of which ten were in trauma and orthopaedic surgery patients (four exclusively examined hip fractures), five were in cardiac surgery patients, and four were in vascular surgery patients. Due to substantial overlap in reviews, eighteen reviews were analysed in detail finding the widely examined and consistent risk factors were increasing age, nursing home residency, pre-existing cognitive impairment, psychiatric disorders, cerebrovascular disease, end stage renal failure, low albumin, higher ASA score, and intra-operative blood transfusion. Many other risk factors were examined, but they were either not studied in multiple systematic reviews, or inconsistent either in results or in categorisation (which for many factors was heterogenous even within systematic reviews). There are also a large number of existing prognostic models, many of which remain unvalidated.
Given the wealth of existing literature, future research should avoid simple risk factor evaluation except for novel candidates, validate existing prognostic models where possible, and instead focus on interventional research.
术后谵妄（POD）与死亡率增加、住院时间延长以及随后认知能力下降（包括痴呆）的发生率和严重程度增加有关。在多个外科专业的文献中，已经提出了 POD 的广泛风险因素。然而，其中很少有得到验证，也没有准确的预后模型。因此，我们旨在通过对任何背景下 POD 风险因素的系统评价进行伞式审查，以帮助指导未来的研究，从而对 POD 的现有证据进行映射。
我们系统地搜索了多个医学数据库，以寻找评估任何手术成人 POD 风险因素的系统评价。然后，我们选择了具有最小重叠主要研究的相关综述，并提取了有关单个风险因素的信息。
确定了 35 篇相关综述，其中 10 篇来自创伤和骨科手术患者（4 篇专门研究髋部骨折），5 篇来自心脏手术患者，4 篇来自血管手术患者。由于综述存在大量重叠，因此详细分析了 18 篇综述，发现广泛研究且一致的风险因素是年龄增加、疗养院居住、预先存在的认知障碍、精神疾病、脑血管疾病、终末期肾脏疾病、低白蛋白血症、较高的 ASA 评分和术中输血。还检查了许多其他风险因素，但它们要么没有在多个系统评价中进行研究，要么在结果或分类上不一致（对于许多因素，即使在系统评价内部，分类也是异质的）。此外，还有大量现有的预后模型，其中许多仍未得到验证。
鉴于现有文献的丰富性，未来的研究除了新的候选者外，应避免简单的风险因素评估，尽可能验证现有的预后模型，并将重点放在干预性研究上。
