Martinez Juan Antonio, Belastegui Ana, Basabe Iban, Goicoechea Xabier, Aguirre Cristina, Lizeaga Nerea, Urreta Iratxe, Emparanza Jose Ignacio
Department of Internal Medicine, Donostia University Hospital, San Sebastian, Spain.
BMJ Open. 2012 Sep 14;2(5). doi: 10.1136/bmjopen-2012-001599. Print 2012.
To develop and validate a simple clinical prediction rule, based on variables easily measurable at admission, to identify patients at high risk of developing delirium during their hospital stay on an internal medicine ward.
Prospective study of two cohorts of patients admitted between 1 May and 30 June 2008 (derivation cohort), and between 1 May and 30 June 2009 (validation cohort).
A tertiary hospital in Donostia-Gipuzkoa (Spain).
In total 397 patients participated in the study. The mean age and incidence of delirium were 75.9 years and 13%, respectively, in the derivation cohort, and 75.8 years and 25% in the validation cohort.
The predictive variables analysed and finally included in the rule were: being aged 85 years old or older, being dependent in five or more activities of daily living, and taking two or more psychotropic drugs (antipsychotics, benzodiazepines, antidepressants, anticonvulsant and/or antidementia drugs). The variable of interest was delirium as defined by the short Confusion Assessment Method, which assesses four characteristics: acute onset and fluctuating course, inattention, disorganised thinking and altered level of consciousness.
We developed a rule in which the individual risk of delirium is obtained by adding one point for each criterion met (age≥85, high level of dependence, and being on psychotropic medication). The result is considered positive if the score is ≥1. The rule accuracy was: sensitivity=93.4% (95% CI 85.5% to 97.2%), specificity=60.6% (95% CI 54.1% to 66.8%), positive predictive value=44.4% (95% CI 36.9% to 52.1%) and negative predictive value=96.5% (95% CI: 92% to 98.5%). The area under the receiver operator characteristic (ROC) curve was 0.85 for the validation cohort.
The presence or absence of any of the three predictive factors (age≥85, high level of dependence and psychotropic medication) allowed us to classify patients on internal medicine wards according to the risk of developing delirium. The simplicity of the variables in our clinical prediction rule means that the data collection required is feasible in busy medicine units.
基于入院时易于测量的变量，制定并验证一种简单的临床预测规则，以识别在内科病房住院期间发生谵妄的高危患者。
对2008年5月1日至6月30日入院的两组患者（推导队列）以及2009年5月1日至6月30日入院的两组患者（验证队列）进行前瞻性研究。
西班牙多诺斯蒂亚 - 吉普斯夸的一家三级医院。
共有397名患者参与了该研究。推导队列中患者的平均年龄和谵妄发生率分别为75.9岁和13%，验证队列中分别为75.8岁和25%。
分析并最终纳入该规则的预测变量为：年龄85岁及以上、日常生活中五项及以上活动依赖他人、服用两种及以上精神药物（抗精神病药、苯二氮䓬类药物、抗抑郁药、抗惊厥药和/或抗痴呆药）。感兴趣的变量是由简易精神状态检查表定义的谵妄，该检查表评估四个特征：急性起病且病情波动、注意力不集中、思维紊乱和意识水平改变。
我们制定了一条规则，即根据符合的每条标准（年龄≥85岁、高度依赖、服用精神药物）加一分来得出个体发生谵妄的风险。如果得分≥1，则结果被视为阳性。该规则的准确性为：敏感性=93.4%（95%置信区间85.5%至97.2%），特异性=60.6%（95%置信区间54.1%至66.8%），阳性预测值=44.4%（95%置信区间36.9%至52.1%），阴性预测值=96.5%（95%置信区间：92%至98.5%）。验证队列的受试者工作特征（ROC）曲线下面积为0.85。
存在或不存在这三个预测因素（年龄≥85岁、高度依赖和服用精神药物）中的任何一个，使我们能够根据发生谵妄的风险对内科病房的患者进行分类。我们临床预测规则中变量的简单性意味着在繁忙的医疗科室进行所需的数据收集是可行的。
