Inouye S K, Viscoli C M, Horwitz R I, Hurst L D, Tinetti M E
Yale University School of Medicine, New Haven Connecticut.
Ann Intern Med. 1993 Sep 15;119(6):474-81. doi: 10.7326/0003-4819-119-6-199309150-00005.
To prospectively develop and validate a predictive model for the occurrence of new delirium in hospitalized elderly medical patients based on characteristics present at admission.
Two prospective cohort studies done in tandem.
University teaching hospital.
The development cohort included 107 hospitalized general medical patients 70 years or older who did not have dementia or delirium at admission. The validation cohort included 174 comparable patients.
Patients were assessed daily for delirium using a standardized, validated instrument. The predictive model developed in the initial cohort was then validated in a separate cohort of patients.
Delirium developed in 27 of 107 patients (25%) in the development cohort. Four independent baseline risk factors for delirium were identified using proportional hazards analysis: These included vision impairment (adjusted relative risk, 3.5; 95% Cl, 1.2 to 10.7); severe illness (relative risk, 3.5; Cl, 1.5 to 8.2); cognitive impairment (relative risk, 2.8; Cl, 1.2 to 6.7); and a high blood urea nitrogen/creatinine ratio (relative risk, 2.0; Cl, 0.9 to 4.6). A risk stratification system was developed by assigning 1 point for each risk factor present. Rates of delirium for low- (0 points), intermediate- (1 to 2 points), and high-risk (3 to 4 points) groups were 9%, 23%, and 83% (P < 0.0001), respectively. The corresponding rates in the validation cohort, in which 29 of 174 patients (17%) developed delirium, were 3%, 16%, and 32% (P < 0.002). The rates of death or nursing home placement, outcomes potentially related to delirium, were 9%, 16%, and 42% (P = 0.02) in the development cohort and 3%, 14%, and 26% (P = 0.007) in the validation cohort.
Delirium among elderly hospitalized patients is common, and a simple predictive model based on four risk factors can be used at admission to identify elderly persons at the greatest risk.
前瞻性地开发并验证一种基于入院时特征的预测模型，用于预测老年内科住院患者新发谵妄的发生情况。
两项同步进行的前瞻性队列研究。
大学教学医院。
开发队列包括107名70岁及以上的住院普通内科患者，他们入院时没有痴呆或谵妄。验证队列包括174名类似患者。
使用标准化、经过验证的工具每天对患者进行谵妄评估。然后在另一组患者中验证在初始队列中开发的预测模型。
开发队列中的107名患者中有27名（25%）发生谵妄。使用比例风险分析确定了谵妄的四个独立基线风险因素：包括视力障碍（调整后相对风险为3.5；95%可信区间为1.2至10.7）；重病（相对风险为3.5；可信区间为1.5至8.2）；认知障碍（相对风险为2.8；可信区间为1.2至6.7）；以及高血尿素氮/肌酐比值（相对风险为2.0；可信区间为0.9至4.6）。通过为每个存在的风险因素赋予1分来建立风险分层系统。低风险（0分）、中度风险（1至2分）和高风险（3至4分）组的谵妄发生率分别为9%、23%和83%（P<0.0001）。在验证队列中，174名患者中有29名（17%）发生谵妄，相应的发生率分别为3%、16%和32%（P<0.002）。在开发队列中，与谵妄可能相关的死亡或入住养老院的发生率分别为9%、16%和42%（P = 0.02），在验证队列中分别为3%、14%和26%（P = 0.007）。
老年住院患者谵妄很常见，基于四个风险因素的简单预测模型可在入院时用于识别风险最高的老年人。
