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Validating the Fluctuating Mental Status Evaluation in Neurocritically Ill Patients With Acute Stroke

OBJECTIVES

Neurocritically ill patients are at high risk for developing delirium, which can worsen the long-term outcomes of this vulnerable population. However, existing delirium assessment tools do not account for neurologic deficits that often interfere with conventional testing and are therefore unreliable in neurocritically ill patients. We aimed to determine the accuracy and predictive validity of the Fluctuating Mental Status Evaluation (FMSE), a novel delirium screening tool developed specifically for neurocritically ill patients.

DESIGN

Prospective validation study.

SETTING

Neurocritical care unit at an academic medical center.

PATIENTS

One hundred thirty-nine neurocritically ill stroke patients (mean age, 63.9 [ sd , 15.9], median National Institutes of Health Stroke Scale score 11 [interquartile range, 2-17]).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Expert raters performed daily Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition-based delirium assessments, while paired FMSE assessments were performed by trained clinicians. We analyzed 717 total noncomatose days of paired assessments, of which 52% ( n = 373) were rated by experts as days with delirium; 53% of subjects were delirious during one or more days. Compared with expert ratings, the overall accuracy of the FMSE was high (area under the curve [AUC], 0.85; 95% CI, 0.82-0.87). FMSE scores greater than or equal to 1 had 86% sensitivity and 74% specificity on a per-assessment basis, while scores greater than or equal to 2 had 70% sensitivity and 88% specificity. Accuracy remained high in patients with aphasia (FMSE ≥ 1: 82% sensitivity, 64% specificity; FMSE ≥ 2: 64% sensitivity, 84% specificity) and those with decreased arousal (FMSE ≥ 1: 87% sensitivity, 77% specificity; FMSE ≥ 2: 71% sensitivity, 90% specificity). Positive FMSE assessments also had excellent accuracy when predicting functional outcomes at discharge (AUC, 0.86 [95% CI, 0.79-0.93]) and 3 months (AUC, 0.85 [95% CI, 0.78-0.92]).

CONCLUSIONS

In this validation study, we found that the FMSE was an accurate delirium screening tool in neurocritically ill stroke patients. FMSE scores greater than or equal to 1 indicate "possible" delirium and should be used when prioritizing sensitivity, whereas scores greater than or equal to 2 indicate "probable" delirium and should be used when prioritizing specificity.

Rest-activity patterns associated with delirium in patients with intracerebral hemorrhage

BACKGROUND

Delirium is an acute cognitive disturbance frequently characterized by abnormal psychomotor activity and sleep-wake cycle disruption. However, the degree to which delirium affects activity patterns in the acute period after stroke is unclear. We aimed to examine these patterns in a cohort of patients with intracerebral hemorrhage (ICH).

METHODS

We enrolled 40 patients with intracerebral hemorrhage (ICH) who had daily DSM-5-based delirium assessments. Continuous activity measurements were captured using bilateral wrist actigraphs throughout each patient's admission. Activity data were collected in 1-min intervals, with "rest" defined as periods with zero activity. We compared differences in activity based on delirium status across multiple time intervals using multivariable models adjusted for age, ICH severity, and mechanical ventilation.

RESULTS

There were 279 days of actigraphy monitoring, of which 199 (71%) were rated as days with delirium. In multivariable analyses, delirium was associated with 98.4 (95% CI 10.4-186.4) fewer daily minutes of rest, including 5.3% (95% CI -0.1-10.1%) fewer minutes during daytime periods (06:00-21:59) and 10.2% (95% CI 1.9-18.4%) fewer minutes during nocturnal periods (22:00-5:59), with higher levels of activity across multiple individual hourly intervals (18:00-21:00, 23:00-03:00, and 04:00-08:00). These differences were even more pronounced in hyperactive or mixed delirium, although even hypoactive delirium was associated with more activity during multiple time periods.

CONCLUSIONS

Post-stroke delirium is associated with less rest and higher overall levels of activity, especially during nocturnal periods.

A Pilot Study of the Fluctuating Mental Status Evaluation: A Novel Delirium Screening Tool for Neurocritical Care Patients

BACKGROUND

Delirium occurs frequently in patients with stroke and neurocritical illness but is often underrecognized. We developed a novel delirium screening tool designed specifically for neurocritical care patients called the fluctuating mental status evaluation (FMSE) and aimed to test its usability and accuracy in a representative cohort of patients with intracerebral hemorrhage (ICH).

METHODS

We performed a single-center prospective study in a pilot cohort of patients with ICH who had daily delirium assessments throughout their admission. Reference-standard expert ratings were performed each afternoon using criteria from the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, and were derived from bedside assessments and clinical data from the preceding 24 h. Paired FMSE assessments were performed by patients' clinical nurses after receiving brief one-on-one training from research staff. Nursing assessments were aggregated over 24-h periods (including day and night shifts), and accuracy of the FMSE was analyzed in patients who were not comatose to determine optimal scoring thresholds.

RESULTS

We enrolled 40 patients with ICH (mean age 71.1 ± 12.2, 55% male, median National Institutes of Health Stroke Scale score 16.5 [interquartile range 12-20]), of whom 85% (n = 34) experienced delirium during their hospitalization. Of 308 total coma-free days with paired assessments, 208 (68%) were rated by experts as days with delirium. Compared with expert ratings, FMSE scores ≥ 1 had 86% sensitivity and 73% specificity on a per-day basis, whereas FMSE scores ≥ 2 had 68% sensitivity and 82% specificity. Accuracy remained high in patients with aphasia (FMSE scores ≥ 1: 83% sensitivity, 77% specificity; FMSE scores ≥ 2: 68% sensitivity, 85% specificity) and decreased arousal (FMSE scores ≥ 1: 80% sensitivity, 100% specificity; FMSE scores ≥ 2: 73% sensitivity, 100% specificity).

CONCLUSIONS

In this pilot study, the FMSE achieved a high sensitivity and specificity in detecting delirium. Follow-up validation studies in a larger more diverse cohort of neurocritical care patients will use score cutoffs of ≥ 1 as "possible" delirium and ≥ 2 as "probable" delirium.

Impact of Delirium on Outcomes After Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

Delirium portends worse outcomes after intracerebral hemorrhage (ICH), but it is unclear if symptom resolution or postacute care intensity may mitigate its impact. We aimed to explore differences in outcome associated with delirium resolution before hospital discharge, as well as the potential mediating role of postacute discharge site.

METHODS

We performed a single-center cohort study on consecutive ICH patients over 2 years. Delirium was diagnosed according to DSM-5 criteria and further classified as persistent or resolved based on delirium status at hospital discharge. We determined the impact of delirium on unfavorable 3-month outcome (modified Rankin Scale score, 4-6) using logistic regression models adjusted for established ICH predictors, then used mediation analysis to examine the indirect effect of delirium via postacute discharge site.

RESULTS

Of 590 patients (mean age 70.5±15.5 years, 52% male, 83% White), 59% (n=348) developed delirium during hospitalization. Older age and higher ICH severity were delirium risk factors, but only younger age predicted delirium resolution, which occurred in 75% (161/215) of ICH survivors who had delirium. Delirium was strongly associated with unfavorable outcome, but patients with persistent delirium fared worse (adjusted odds ratio [OR], 7.3 [95% CI, 3.3-16.3]) than those whose delirium resolved (adjusted OR, 3.1 [95% CI, 1.8-5.5]). Patients with delirium were less likely to be discharged to inpatient rehabilitation than skilled nursing facilities (adjusted OR, 0.31 [95% CI, 0.17-0.59]), and postacute care site partially mediated the relationship between delirium and functional outcome in ICH survivors, leading to a 25% reduction in the effect of delirium (without mediator: adjusted OR, 3.0 [95% CI, 1.7-5.6]; with mediator: adjusted OR, 2.3 [95% CI, 1.2-4.3]).

CONCLUSIONS

Acute delirium resolves in most patients with ICH by hospital discharge, which was associated with better outcomes than in patients with persistent delirium. The impact of delirium on outcomes may be further mitigated by postacute rehabilitation.