Confusion Assessment Method Severity Research Articles

The Relationship Between Rejection of Care Behaviors and Pain and Delirium Severity in Hospital Dementia Care.

Rejection of care is common in hospitalized persons living with dementia. However, distinguishing between rejection of care behaviors related to care practices or other causes, such as pain or delirium, is challenging. The purpose of this study is to further understand the relationship between rejection of care and pain and delirium in hospitalized patients with dementia by identifying which rejection of care behaviors are associated with pain and delirium. Care encounters between hospitalized patients with dementia (n = 16) and nursing staff (n = 53) were observed on 88 separate occasions across 35 days. Rejection of care was measured using the 13 behaviors from the Resistiveness to Care Scale. Pain and delirium severity were measured using a variety of scales including the Pain Assessment in Advanced Dementia Scale, Checklist of Nonverbal Pain Indicators, and numeric rating scale for pain severity and the Confusion Assessment Method-Severity short form and Delirium Observation Screening Scale for delirium severity. Linear mixed modeling was used to determine the relationship between rejection of care behaviors and pain and delirium severity for each measure. About 48.9% of the observations included rejection of care, 49.9% included a patient in pain, and 12.5% included a patient with delirium. Cry, push away, scream/yell, and turn away indicated a higher pain severity across pain measures. No rejection of care behaviors were found to indicate delirium severity. Certain rejection of care behaviors may be helpful in identifying pain in hospitalized patients with dementia, suggesting that caregivers should be cognizant of pain when these rejection of care behaviors are present. However, in this sample rejection of care behaviors was not found to be useful for identifying delirium severity in hospital dementia care.

Moderate-to-high risk of obstructive sleep apnea with excessive daytime sleepiness is associated with postoperative neurocognitive disorders: a prospective one-year follow-up cohort study.

Few studies found that obstructive sleep apnea (OSA) may be related to postoperative neurocognitive disorders (PND) including postoperative delirium (POD) and cognitive decline (POCD) in the early postoperative period. However, the results are controversial and need further verification, and no research has explored the effect of OSA on the incidence of PND during the 1-year follow-up periods. Furthermore, OSA patients with excessive daytime sleepiness (EDS) as a severe phenotype have more significant neurocognitive impairments, but the relationship between OSA with EDS and PND within 1 year after surgery has not been studied. To explore the effect of moderate-to-high risk of OSA and the moderate-to-high risk of OSA with EDS on PND within 1 year after surgery. In this prospective cohort study, including 227 older patients, moderate-to-high risk of OSA (using STOP-BANG), subjective EDS (using Epworth Sleepiness Scale), and objective EDS (using Actigraphy) were selected as exposures. Key outcomes included POD during hospitalization (using Confusion Assessment Method-Severity), POCD at discharge, 1-month and 1-year after surgery (using Mini-Mental State Examination and Telephone Interview for Cognitive Status-40). We applied multiple logistic regression models to estimate the effect of moderate-to-high risk of OSA and moderate-to-high risk of OSA with EDS on PND. In the multivariate analysis, moderate-to-high risk of OSA was not associated with POD during hospitalization and POCD at discharge, 1-month, and 1-year after surgery (p > 0.05). However, the moderate-to-high risk of OSA with subjective EDS was related to POCD at discharge compared to the moderate-to-high risk of OSA or normal group (no moderate-to-high risk of OSA and no EDS) (p < 0.05). In addition, moderate-to-high risk of OSA with objective EDS was associated with POCD at discharge, 1-month, and 1-year postoperatively compared to the moderate-to-high risk of OSA or normal group (p < 0.05). Moderate-to-high risk of OSA with EDS, not moderate-to-high risk of OSA alone, was a clinically helpful predictor for POCD within 1-year after surgery and should be routinely assessed before surgery.

Preoperative homocysteine modifies the association between postoperative C-reactive protein and postoperative delirium.

BackgroundHomocysteine and C-reactive protein (CRP) may serve as biomarkers of postoperative delirium. We set out to compare the role of blood concentration of homocysteine versus CRP in predicting postoperative delirium in patients.Materials and methodsIn this prospective observational cohort study, the plasma concentration of preoperative homocysteine and postoperative CRP was measured. Delirium incidence and severity within 3 days postoperatively were determined using the Confusion Assessment Method and Confusion Assessment Method-Severity algorithm.ResultsOf 143 participants [69% female, median (interquartile range, 25th–75th) age of 71 (67–76) years] who had knee or hip surgery under general anesthesia, 44 (31%) participants developed postoperative delirium. Postoperative plasma concentration of CRP was associated with postoperative delirium incidence [adjusted odds ratio (OR) per one standard deviation change in CRP: 1.51; 95% Confidence Interval (CI): 1.05, 2.16; P = 0.026], and severity [in which each one standard deviation increase in postoperative CRP was associated with a 0.47 point (95% CI: 0.18–0.76) increase in the severity of delirium, P = 0.002] after adjusting age, sex, preoperative Mini-Mental State Examination score and the days when postoperative CRP was measured. A statistically significant interaction (adjusted P = 0.044) was also observed, in which the association between postoperative plasma concentration of CRP and postoperative delirium incidence was stronger in the participants with lower preoperative plasma concentrations of homocysteine compared to those with higher preoperative levels.ConclusionPending validation studies, these data suggest that preoperative plasma concentration of homocysteine modifies the established association between postoperative plasma concentration of CRP and postoperative delirium incidence.

VE-CAM-S: Visual EEG-Based Grading of Delirium Severity and Associations With Clinical Outcomes.

This prospective, single-center, observational cohort study was conducted from August 2015 to December 2016 and October 2018 to December 2019. Academic medical center, all inpatient wards. Adult inpatients undergoing a clinical EEG recording; excluded if deaf, severely aphasic, developmentally delayed, non-English speaking (if noncomatose), or if goals of care focused primarily on comfort measures. Four-hundred six subjects were assessed; two were excluded due to technical EEG difficulties. None. A machine learning model, with visually coded EEG features as inputs, was developed to produce scores that correlate with behavioral assessments of delirium severity (Confusion Assessment Method-Severity [CAM-S] Long Form [LF] scores) or coma; evaluated using Spearman R correlation; area under the receiver operating characteristic curve (AUC); and calibration curves. Associations of Visual EEG Confusion Assessment Method Severity (VE-CAM-S) were measured for three outcomes: functional status at discharge (via Glasgow Outcome Score [GOS]), inhospital mortality, and 3-month mortality. Four-hundred four subjects were analyzed (mean [sd] age, 59.8 yr [17.6 yr]; 232 [57%] male; 320 [79%] White; 339 [84%] non-Hispanic); 132 (33%) without delirium or coma, 143 (35%) with delirium, and 129 (32%) with coma. VE-CAM-S scores correlated strongly with CAM-S scores (Spearman correlation 0.67 [0.62-0.73]; p < 0.001) and showed excellent discrimination between levels of delirium (CAM-S LF = 0 vs ≥ 4, AUC 0.85 [0.78-0.92], calibration slope of 1.04 [0.87-1.19] for CAM-S LF ≤ 4 vs ≥ 5). VE-CAM-S scores were strongly associated with important clinical outcomes including inhospital mortality (AUC 0.79 [0.72-0.84]), 3-month mortality (AUC 0.78 [0.71-0.83]), and GOS at discharge (0.76 [0.69-0.82]). VE-CAM-S is a physiologic grading scale for the severity of symptoms in the setting of delirium and coma, based on visually assessed electroencephalography features. VE-CAM-S scores are strongly associated with clinical outcomes.

Physiological Assessment of Delirium Severity: The Electroencephalographic Confusion Assessment Method Severity Score (E-CAM-S).

Delirium is a common and frequently underdiagnosed complication in acutely hospitalized patients, and its severity is associated with worse clinical outcomes. We propose a physiologically based method to quantify delirium severity as a tool that can help close this diagnostic gap: the Electroencephalographic Confusion Assessment Method Severity Score (E-CAM-S). Retrospective cohort study. Single-center tertiary academic medical center. Three-hundred seventy-three adult patients undergoing electroencephalography to evaluate altered mental status between August 2015 and December 2019. None. We developed the E-CAM-S based on a learning-to-rank machine learning model of forehead electroencephalography signals. Clinical delirium severity was assessed using the Confusion Assessment Method Severity (CAM-S). We compared associations of E-CAM-S and CAM-S with hospital length of stay and inhospital mortality. E-CAM-S correlated with clinical CAM-S (R = 0.67; p < 0.0001). For the overall cohort, E-CAM-S and CAM-S were similar in their strength of association with hospital length of stay (correlation = 0.31 vs 0.41, respectively; p = 0.082) and inhospital mortality (area under the curve = 0.77 vs 0.81; p = 0.310). Even when restricted to noncomatose patients, E-CAM-S remained statistically similar to CAM-S in its association with length of stay (correlation = 0.37 vs 0.42, respectively; p = 0.188) and inhospital mortality (area under the curve = 0.83 vs 0.74; p = 0.112). In addition to previously appreciated spectral features, the machine learning framework identified variability in multiple measures over time as important features in electroencephalography-based prediction of delirium severity. The E-CAM-S is an automated, physiologic measure of delirium severity that predicts clinical outcomes with a level of performance comparable to conventional interview-based clinical assessment.

Science, Medicine, and the Anesthesiologist

Science, Medicine, and the Anesthesiologist

One-Year Medicare Costs Associated With Delirium in Older Patients Undergoing Major Elective Surgery

Delirium is a common, serious, and potentially preventable problem for older adults, associated with adverse outcomes. Coupled with its preventable nature, these adverse sequelae make delirium a significant public health concern; understanding its economic costs is important for policy makers and health care leaders to prioritize care. To evaluate current 1-year health care costs attributable to postoperative delirium in older patients undergoing elective surgery. This prospective cohort study included 497 patients from the Successful Aging after Elective Surgery (SAGES) study, an ongoing cohort study of older adults undergoing major elective surgery. Patients were enrolled from June 18, 2010, to August 8, 2013. Eligible patients were 70 years or older, English-speaking, able to communicate verbally, and scheduled to undergo major surgery at 1 of 2 Harvard-affiliated hospitals with an anticipated length of stay of at least 3 days. Eligible surgical procedures included total hip or knee replacement; lumbar, cervical, or sacral laminectomy; lower extremity arterial bypass surgery; open abdominal aortic aneurysm repair; and open or laparoscopic colectomy. Data were analyzed from October 15, 2019, to September 15, 2020. Major elective surgery and hospitalization. Cumulative and period-specific costs (index hospitalization, 30-day, 90-day, and 1-year follow-up) were examined using Medicare claims and extensive clinical data. Total inflation-adjusted health care costs were determined using data from Medicare administrative claims files for the 2010 to 2014 period. Delirium was rated using the Confusion Assessment Method. We also examined whether increasing delirium severity was associated with higher cumulative and period-specific costs. Delirium severity was measured with the Confusion Assessment Method-Severity long form. Regression models were used to determine costs associated with delirium after adjusting for patient demographic and clinical characteristics. Of the 566 patients who were eligible for the study, a total of 497 patients (mean [SD] age, 76.8 [5.1] years; 281 women [57%]; 461 White participants [93%]) were enrolled after exclusion criteria were applied. During the index hospitalization, 122 patients (25%) developed postoperative delirium, whereas 375 (75%) did not. Patients with delirium had significantly higher unadjusted health care costs than patients without delirium (mean [SD] cost, $146 358 [$140 469] vs $94 609 [$80 648]). After adjusting for relevant confounders, the cumulative health care costs attributable to delirium were $44 291 (95% CI, $34 554-$56 673) per patient per year, with the majority of costs coming from the first 90 days: index hospitalization ($20 327), subsequent rehospitalizations ($27 797), and postacute rehabilitation stays ($2803). Health care costs increased directly and significantly with level of delirium severity (none-mild, $83 534; moderate, $99 756; severe, $140 008), suggesting an exposure-response relationship. The adjusted mean cumulative costs attributable to severe delirium were $56 474 (95% CI, $40 927-$77 440) per patient per year. Extrapolating nationally, the health care costs attributable to postoperative delirium were estimated at $32.9 billion (95% CI, $25.7 billion-$42.2 billion) per year. These findings suggest that the economic outcomes of delirium and severe delirium after elective surgery are substantial, rivaling costs associated with cardiovascular disease and diabetes. These results highlight the need for policy imperatives to address delirium as a large-scale public health issue.

Pain Incidence, Treatment, and Associated Symptoms in Hospitalized Persons with Dementia

BackgroundModerate to severe pain has been frequently reported in hospitalized older adults. Pain in hospitalized persons with dementia within the context of other common symptoms, functional decline, delirium, and behavioral and psychological symptoms of dementia (BPSD), has received little attention. AimsDescribe the incidence of pain, the pharmacologic management of pain, and the association of pain with physical function, delirium, and BPSD in hospitalized persons with dementia. DesignDescriptive, cross-sectional study. SettingSix medical units in three hospitals. ParticipantsBaseline data from 299 hospitalized persons with dementia enrolled in the Family-centered Function-focused Care (Fam-FFC) cluster randomized trial. MethodsDescriptive analyses of pain used the Pain Assessment in Advanced Dementia (PAINAD) scale and the use of medication for pain management. Linear regression analyses tested relationships between pain and:1) physical function (Barthel Index), 2) delirium severity (Confusion Assessment Method Severity Short Form) and 3) BPSD severity (Neuropsychiatric Inventory- Questionnaire). ResultsThe majority of the sample was female (61.9%), non-Hispanic (98%), and Black (53.2%), with a mean age of 81.58 (SD=8.54).Of the 299 patients, 166 (56%) received pain medication. Of the 108 individuals who demonstrated pain, 40% (n=43) did not receive pain medication. When controlling for age, gender, cognition, and comorbidities, pain was significantly associated with function, delirium severity, and BPSD severity. ConclusionsResults suggest that pain may be undertreated in hospitalized persons with dementia, and should be considered upon admission to optimize function, decrease delirium, and prevent or decrease BPSD.

New Delirium Severity Indicators: Generation and Internal Validation in the Better Assessment of Illness (BASIL) Study

Background: Delirium is a common and preventable geriatric syndrome. Moving beyond the binary classification of delirium present/absent, delirium severity represents a potentially important outcome for evaluating preventive and treatment interventions and tracking the course of patients. Although several delirium severity assessment tools currently exist, most have been developed in the absence of advanced measurement methodology and have not been evaluated with rigorous validation studies. Objective: We aimed to report our development of new delirium severity items and the results of item reduction and selection activities guided by psychometric analysis of data derived from a field study. Methods: Building on our literature review of delirium instruments and expert panel process to identify domains of delirium severity, we adapted items from existing delirium severity instruments and generated new items. We then fielded these items among a sample of 352 older hospitalized patients. Results: We used an expert panel process and psychometric data analysis techniques to narrow a set of 303 potential items to 17 items for use in a new delirium severity instrument. The 17-item set demonstrated good internal validity and favorable psychometric characteristics relative to comparator instruments, including the Confusion Assessment Method – Severity (CAM-S) score, the Delirium Rating Scale Revised 98, and the Memorial Delirium Assessment Scale. Conclusion: We more fully conceptualized delirium severity and identified characteristics of an ideal delirium severity instrument. These characteristics include an instrument that is relatively quick to administer, is easy to use by raters with minimal training, and provides a severity rating with good content validity, high internal consistency reliability, and broad domain coverage across delirium symptoms. We anticipate these characteristics to be represented in the subsequent development of our final delirium severity instrument.

Characterisation and outcome of neuropsychiatric symptoms in patients with anti-NMDAR encephalitis.

Encephalitis due to anti-N-methyl-D-aspartate receptor antibodies (ANMDARE) is the most frequent immune-mediated encephalitis. It is distinguished by the subacute onset of neuropsychiatric symptoms. To evaluate the characteristic neuropsychiatric symptoms and their outcome in patients diagnosed with ANMDARE. This was a prospective, longitudinal study in patients with a diagnostic suspicion of ANMDARE that presented to the National Institute of Neurology from March 2018 to February 2019. A comparative analysis of two groups (positive N-methyl-D-aspartate receptor [NMDAR] vs. negative NMDAR antibodies in cerebrospinal fluid [CSF]) was done on admission and at discharge. Neuropsychiatric systematic assessments included the Neuropsychiatric Inventory Questionnaire, the Bush Francis Catatonia Rating Scale, the Confusion Assessment Method Severity, the Montreal Cognitive Assessment, and the Overt Agitation Severity Scale. 24 individuals were analysed: 14 had positive NMDAR antibodies, and 10 had negative NMDAR antibodies in CSF. On admission, agitation/aggression, euphoria/exaltation, and disinhibition were more common in patients with positive antibodies. Excited catatonia and delirium were diagnosed more frequently in patients with positive antibodies. At discharge, there was an important decrease in neuropsychiatric symptoms, but substantial cognitive impairment remained. The mean hospitalisation length was 41.71 (SD 39.33) days for patients with definitive ANMDARE (p 0.259). Neuropsychiatric symptoms profile in ANMDARE was associated with the early onset of euphoria/exaltation and disinhibition, accompanied by marked psychomotor agitation. When ANMDARE was suspected, the presence of excited-type catatonia and delirium showed a tendency to predict definitive ANMDARE. At discharged, most patients recovered from catatonia, delirium, and psychosis, but marked cognitive symptoms, anxiety, and depression persisted at discharge.

Apolipoprotein E genotype and the association between C-reactive protein and postoperative delirium: Importance of gene-protein interactions

IntroductionApolipoprotein E (APOE) status may modify the risk of postoperative delirium conferred by inflammation. MethodsWe tested whether APOE modifies the established association between C-reactive protein (CRP) and delirium incidence, severity, and duration in 553 noncardiac surgical patients aged 70 and older. High postoperative plasma CRP (≥234.12 mg/L) was defined by the highest sample-based quartile. Delirium was determined using the Confusion Assessment Method and chart review, and severity was determined by the Confusion Assessment Method––Severity score. ResultsAPOE ε4 carrier prevalence was 19%, and postoperative delirium occurred in 24%. The relationship between CRP and delirium incidence, severity, and duration differed by ε4 status. Among ε4 carriers, there was a strong relationship between high CRP (vs. low CRP) and delirium incidence (relative risk [95% confidence interval], 3.0 [1.4–6.7]); however, no significant association was observed among non-ε4 carriers (relative risk [95% CI], 1.2 [0.8–1.7]). DiscussionOur findings raise the possibility that APOE ε4 carrier status may modify the relationship between postoperative day 2 CRP levels and postoperative delirium.

The study protocol for a randomized, controlled trial of acupuncture versus a sham procedure versus standard care alone for the treatment of delirium in acutely hospitalized older adults with a medical illness

BackgroundMany hospitalized older adults experience delirium, but treatment options are limited. Acupuncture has been shown to improve cognitive function and reduce agitation in dementia. We hypothesize that acupuncture, when compared with a sham intervention, will reduce the duration and severity of delirium, normalize delirium biomarkers, and improve clinical outcomes related to delirium in acutely hospitalized older adults with a medical illness. MethodsThis three-arm, prospective, randomized, clinical trial will evaluate adults aged over 65 years who are acutely hospitalized to an internal-medicine ward and diagnosed with delirium or subsyndromal delirium. The 288 patients (96 in each of three groups) will be randomly allocated to receive either daily true acupuncture with usual care, a daily sham procedure with usual care, or usual care only in a 1:1:1 distribution for up to one week or until the patient is delirium-free for over 48 h. Other delirium and clinical interventions will remain unchanged. Delirium will be diagnosed using DSM-5 criteria and its severity will be assessed using the long Confusion Assessment Method Severity (CAM-S) tool. OutcomesThe primary study outcome will be the daily CAM-S score over 7 days between the three groups. Secondary outcomes will include time to first resolution of the delirium (over 7 days), the proportion of days spent delirium-free, daily antipsychotic use, daily pain scores, sleep quality, morning serum cortisol and T3 levels, and midnight urinary cortisol/creatinine ratio, all determined twice a week, and delirium-related complications. Hospital mortality, duration of hospital stay and functional status at discharge will also be compared between the three groups. Adverse events potentially related to acupuncture will be evaluated daily. The cost-effectiveness of acupuncture will be estimated. ConclusionThis novel randomized study will evaluate both the specific and the non-specific effects of acupuncture on delirium, and related outcomes, and its safety. Potential mechanism(s) of action for acupuncture in reducing delirium will be explored and healthcare-related costs estimated. Positive study results may prove pivotal in facilitating a multimodal, non-pharmacologic, integrative approach to delirium treatment among older, medical inpatients.

Harmonization of delirium severity instruments: a comparison of the DRS-R-98, MDAS, and CAM-S using item response theory

BackgroundThis study aimed to describe the level of agreement of three commonly used delirium instruments: the Delirium Rating Scale-Revised-98 (DRS-R-98), Memorial Delirium Assessment Scale (MDAS), and Confusion Assessment Method-Severity (CAM-S).MethodsWe used data from a prospective clinical research study, in which a team of trained lay interviewers administered each instrument along with supporting interview and cognitive assessments in the same group of patients daily while in the hospital (N = 352). We used item response theory methods to co-calibrate the instruments.ResultsThe latent traits underlying the three measures, capturing the severity of a delirium assessment, had a high degree of correlation (r’s > .82). Unidimensional factor models fit well, facilitating co-calibration of the instruments. Across instruments, the less intense symptoms were generally items reflecting cognitive impairment. Although the intensity of delirium severity for most in the sample was relatively low, many of the item thresholds for the delirium severity scales are high (i.e., in the more severe range of the latent ability distribution). This indicates that even people with severe delirium may have a low probability of endorsing the highest severity categories for many items. Co-calibration enabled us to derive crosswalks to map delirium severity scores among the delirium instruments.ConclusionThese delirium instruments measure the same underlying construct of delirium severity. Relative locations of items may inform design of refined measurement instruments. Mapping of overall delirium severity scores across the delirium severity instruments enabled us to derive crosswalks, which allow scores to be translated across instruments, facilitating comparison and combination of delirium studies for integrative analysis.

End-Tidal Hypocapnia Under Anesthesia Predicts Postoperative Delirium.

Background: Postoperative delirium (POD) might be associated with anesthetic management, but research has focused on choice or dosage of anesthetic drugs. We examined potential contributions of intraoperative ventilatory and hemodynamic management to POD.Methods: This was a sub-study of the ENGAGES-Canada trial (NCT02692300) involving non-cardiac surgery patients enrolled in Winnipeg, Canada. Patients received preoperative psychiatric and cognitive assessments, and intraoperatively underwent high-fidelity data collection of blood pressure, end-tidal respiratory gases and anesthetic agent concentration. POD was assessed by peak and mean POD scores using the Confusion Assessment Method-Severity (CAM-S) tool. Bivariate and multiple linear regression models were constructed controlling for age, psychiatric illness, and cognitive dysfunction in the examination of deviations in intraoperative end-tidal carbon dioxide (areas over (AOC) and under the curve (AUC)) on POD severity scores.Results: A total of 101 subjects [69 (6) years of age] were studied; 89 had comprehensive intraoperative hemodynamic and end-tidal gas measurements (data recorded at 1 Hz). The incidence of POD was 11.9% (12/101). Age, cognitive dysfunction, anxiety, depression, and intraoperative end-tidal CO2 (AUC) were significant correlates of POD severity. In the multiple regression model, cognitive dysfunction and AUC end-tidal CO2 (0.67 kPa below median intra-operative value) were the only independent significant predictors across both POD severity (mean and peak) scores. There was no association between cumulative anesthetic agent exposure and POD.Conclusions: POD was associated with intraoperative ventilatory management, reflected by low end-tidal CO2 concentrations, but not with cumulative anesthetic drug exposure. These findings suggest that maintenance of intraoperative normocapnia might benefit patients at risk of POD.

Delirium Severity Post-Surgery and its Relationship with Long-Term Cognitive Decline in a Cohort of Patients without Dementia.

Delirium has been associated with more rapid cognitive decline. However, it is unknown whether increased delirium severity is associated with a higher rate of long-term cognitive decline. To evaluate delirium severity and the presence and rate of cognitive decline over 36 months following surgery. We examined patients from the Successful Aging after Elective Surgery Study, who were age ≥70 years undergoing major elective surgery (N = 560). Delirium severity was determined by the peak Confusion Assessment Method-Severity (CAM-S) score for each patient's hospitalization and grouped based on the sample distribution: scores of 0-2, 3-7, and 8-19. A neuropsychological composite, General Cognitive Performance (GCP), and proxy-reported Informant Questionnaire for Cognitive Decline (IQCODE) were used to examine cognitive outcomes following surgery at 0, 1, and 2 months, and then every 6 months for up to 3 years. No significant cognitive decline was observed for patients with peak CAM-S scores 0-2 (-0.17 GCP units/year, 95% confidence interval [CI] -0.35, 0.01). GCP scores decreased significantly in the group with peak CAM-S scores 3-7 (-0.30 GCP units/year, 95% CI -0.51, -0.09), and decreased almost three times faster in the highest delirium severity group (peak CAM-S scores 8-19; -0.82 GCP units/year, 95% CI -1.28, -0.37). A similar association was found for delirium severity and the proportion of patients who developed IQCODE impairment over time. Patients with the highest delirium severity experienced the greatest rate of cognitive decline, which exceeds the rate previously observed for patients with dementia, on serial neuropsychological testing administered over 3 years, with a dose-response relationship between delirium severity and long-term cognitive decline.

Quantifying the Severity of a Delirium Episode Throughout Hospitalization: the Combined Importance of Intensity and Duration.

The ability to determine which episodes of delirium are likely to lead to poor clinical outcomes has remained a major area of challenge. To quantify delirium severity and course over an entire hospitalization using several measures, and to evaluate their predictive validity for 30- and 90-day outcomes post-discharge. Two prospective cohort studies. Analysis was conducted in two independent cohorts of adult patients aged ≥70. Nine delirium episode severity measures were examined: (1) measures reflecting delirium intensity (peak Confusion Assessment Method-Severity [CAM-S] and mean CAM-S score), (2) a measure reflecting delirium intensity and duration (sum of all CAM-S scores, sum of all CAM-S scores on delirium days only, peak CAM-S score x days with delirium), (3) measures requiring information on delirium duration and delirium at discharge (total number of delirium days, percentage of delirium days, delirium at discharge), and (4) a measure of cognitive change. Associations of the delirium episode severity measures with 30- and 90-day post-hospital outcomes (death, nursing home placement, and readmission) relevant to delirium were examined. The delirium episode severity measure that required information on both delirium intensity and duration (sum of all CAM-S scores) was the most strongly associated with 30- and 90-day post-hospital outcomes. Using this measure, the relative risk [95% confidence interval] for death at 30-days increased across levels of sum of all CAM-S scores from 1.0 (referent) to 2.1 [0.8, 5.4] for 'low,' to 2.9 [1.2, 7.1] for 'moderate,' to 6.4 [2.9, 14.0] for 'high' (p for trend <.01). The delirium episode severity measure that included both intensity and duration had the strongest association with important post-hospital outcomes.