The predisposing and precipitating risk factors for delirium in neurosurgery: a prospective cohort study of 949 patients

Neurological Examination Frequency and Time-to-Delirium After Traumatic Brain Injury

BACKGROUND

Frequent neurological examinations in patients with traumatic brain injury (TBI) disrupt sleep-wake cycles and potentially contribute to the development of delirium.

OBJECTIVE

To evaluate the risk of delirium among patients with TBI with respect to their neuro-check frequencies.

METHODS

A retrospective study of patients presenting with TBI at a single level I trauma center between January 2018 and December 2019. The primary exposure was the frequency of neurological examinations (neuro-checks) assigned at the time of admission. Patients admitted with hourly (Q1) neuro-check frequencies were compared with those who received examinations every 2 (Q2) or 4 (Q4) hours. The primary outcomes were delirium and time-to-delirium. The onset of delirium was defined as the first documented positive Confusion Assessment Method for the Intensive Care Unit score.

RESULTS

Of 1552 patients with TBI, 458 (29.5%) patients experienced delirium during their hospital stay. The median time-to-delirium was 1.8 days (IQR: 1.1, 2.9). Kaplan-Meier analysis demonstrated that patients assigned Q1 neuro-checks had the greatest rate of delirium compared with the patients with Q2 and Q4 neuro-checks ( P < .001). Multivariable Cox regression modeling demonstrated that Q2 neuro-checks (hazard ratio: 0.439, 95% CI: 0.33-0.58) and Q4 neuro-checks (hazard ratio: 0.48, 95% CI: 0.34-0.68) were protective against the development of delirium compared with Q1. Other risk factors for developing delirium included pre-existing dementia, tobacco use, lower Glasgow Coma Scale score, higher injury severity score, and certain hemorrhage patterns.

CONCLUSION

Patients with more frequent neuro-checks had a higher risk of developing delirium compared with those with less frequent neuro-checks.

Music to prevent deliriUm during neuroSurgerY (MUSYC): a single-centre, prospective randomised controlled trial

OBJECTIVES

Delirium is a serious complication following neurosurgical procedures. We hypothesise that the beneficial effect of music on a combination of delirium-eliciting factors might reduce delirium incidence following neurosurgery and subsequently improve clinical outcomes.

DESIGN

Prospective randomised controlled trial.

SETTING

Single centre, conducted at the neurosurgical department of the Erasmus Medical Center, Rotterdam, the Netherlands.

PARTICIPANTS

Adult patients undergoing craniotomy were eligible.

INTERVENTIONS

Patients in the intervention group received preferred recorded music before, during and after the operation until day 3 after surgery. Patients in the control group were treated according to standard of clinical care.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary outcome was presence or absence of postoperative delirium within the first 5 postoperative days measured with the Delirium Observation Screening Scale (DOSS) and, in case of a daily mean score of 3 or higher, a psychiatric evaluation with the latest Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria. Secondary outcomes included anxiety, heart rate variability (HRV), depth of anaesthesia, delirium severity and duration, postoperative complications, length of stay and location of discharge.

RESULTS

We enrolled 189 patients (music=95, control=94) from July 2020 through September 2021. Delirium, as assessed by the DOSS, was less common in the music (n=11, 11.6%) than in the control group (n=21, 22.3%, OR:0.49, p=0.048). However, after DSM-5 confirmation, differences in delirium were not significant (4.2% vs 7.4%, OR:0.47, p=0.342). Moreover, music increased the HRV (root mean square of successive differences between normal heartbeats, p=0.012). All other secondary outcomes were not different between groups.

CONCLUSION

Our results support the efficacy of music in reducing the incidence of delirium after craniotomy, as found with DOSS but not after DSM-5 confirmation, substantiated by the effect of music on preoperative autonomic tone. Delirium screening tools should be validated and the long-term implications should be evaluated after craniotomy.

TRIAL REGISTRATION NUMBER

Trialregister.nl: NL8503 and ClinicalTrials.gov: NCT04649450.

Potential Risk Factors for, and Clinical Implications of, Delirium during Inpatient Rehabilitation: A Matched Case-Control Study

OBJECTIVES

To investigate the association between a wide set of baseline characteristics (age, sex, rehabilitation discipline), functional scores [Functional Independence Measure (FIM), cumulative Illness Rating Scale (CIRS)], diseases, and administered drugs and incident delirium in rehabilitation inpatients and, furthermore, to assess clinical implications of developing delirium during rehabilitation.

DESIGN

Matched case-control study based on electronic health record data.

SETTING AND PARTICIPANTS

We studied rehabilitation stays of inpatients admitted between January 1, 2015, and December 31, 2018, to ZURZACH Care, Rehaklinik Bad Zurzach, an inpatient rehabilitation clinic in Switzerland.

METHODS

We conducted unconditional logistic regression analyses to estimate adjusted odds ratios (AORs) with 95% CIs of exposures that were recorded in ≥5 cases and controls.

RESULTS

Among a total of 10,503 rehabilitation stays, we identified 125 validated cases. Older age, undergoing neurologic rehabilitation, a low FIM, and a high CIRS were associated with an increased risk of incident delirium. Being diagnosed with a bacterial infection (AOR 2.62, 95% CI 1.06-6.49), a disorder of fluid, electrolyte, or acid-base balance (AOR 2.76, 95% CI 1.19-6.38), Parkinson's disease (AOR 5.68, 95% CI 2.54-12.68), and administration of antipsychotic drugs (AOR 8.06, 95% CI 4.26-15.22), antiparkinson drugs (AOR 2.86, 95% CI 1.42-5.77), drugs for constipation (AOR 2.11, 95% CI 1.25-3.58), heparins (AOR 2.04, 95% CI 1.29-3.24), or antidepressant drugs (AOR 1.88, 95% CI 1.14-3.10) during rehabilitation, or an increased anticholinergic burden (ACB ≥ 3) (AOR 2.59, 95% CI 1.41-4.73) were also associated with an increased risk of incident delirium.

CONCLUSIONS AND IMPLICATIONS

We identified a set of factors associated with an increased risk of incident delirium during inpatient rehabilitation. Our findings contribute to detect patients at risk of delirium during inpatient rehabilitation.

Dexmedetomidine administration during brain tumour resection for prevention of postoperative delirium: a randomised trial

BACKGROUND

Delirium is common, especially after neurosurgery. Dexmedetomidine might reduce delirium by improving postoperative analgesia and sleep quality. We tested the primary hypothesis that dexmedetomidine administration during intracerebral tumour resection reduces the incidence of postoperative delirium.

METHODS

This randomised, double-blind, placebo-controlled trial was conducted in two tertiary-care hospitals in Beijing. We randomised 260 qualifying patients to either dexmedetomidine (n=130) or placebo (n=130). Subjects assigned to dexmedetomidine were given a loading dose of 0.6 μg kg^-1 followed by continuous infusion at 0.4 μg kg^-1 h^-1 until dural closure; subjects in the placebo group were given comparable volumes of normal saline. The primary outcome was the incidence of delirium, which was assessed with the Confusion Assessment Method twice daily during the initial 5 postoperative days.

RESULTS

The average (standard deviation) age of participating patients was 45 (12) yr, duration of surgery was 4.2 (1.5) h, and patients assigned to dexmedetomidine were given an average of 126 (45) μg of dexmedetomidine. There was less delirium during the initial 5 postoperative days in patients assigned to dexmedetomidine (22%, 28 of 130 patients) than in those given placebo (46%, 60 of 130 patients) with a risk ratio of 0.51 (95% confidence interval: 0.36-0.74, P<0.001). Postoperative pain scores with movement, and recovery and sleep quality were improved by dexmedetomidine (P<0.001). The incidence of safety outcomes was similar in each group.

CONCLUSIONS

Prophylactic intraoperative dexmedetomidine infusion reduced by half the incidence of delirium during the initial 5 postoperative days in patients recovering from elective brain tumour resection.

CLINICAL TRIAL REGISTRATION

NCT04674241.

Predisposing and precipitating risk factors for delirium in gastroenterology and hepatology: Subgroup analysis of 718 patients from a hospital-wide prospective cohort study

BACKGROUND AND AIMS

Delirium is the most common acute neuropsychiatric syndrome in hospitalized patients. Higher age and cognitive impairment are known predisposing risk factors in general hospital populations. However, the interrelation with precipitating gastrointestinal (GI) and hepato-pancreato-biliary (HPB) diseases remains to be determined.

PATIENTS AND METHODS

Prospective 1-year hospital-wide cohort study in 29'278 adults, subgroup analysis in 718 patients hospitalized with GI/HPB disease. Delirium based on routine admission screening and a DSM-5 based construct. Regression analyses used to evaluate clinical characteristics of delirious patients.

RESULTS

Delirium was detected in 24.8% (178/718). Age in delirious patients (median 62 years [IQR 21]) was not different to non-delirious (median 60 years [IQR 22]), p = 0.45). Dementia was the strongest predisposing factor for delirium (OR 66.16 [6.31-693.83], p < 0.001). Functional impairment, and at most, immobility increased odds for delirium (OR 7.78 [3.84-15.77], p < 0.001). Patients with delirium had higher in-hospital mortality rates (18%; OR 39.23 [11.85-129.93], p < 0.001). From GI and HPB conditions, cirrhosis predisposed to delirium (OR 2.11 [1.11-4.03], p = 0.023), while acute renal failure (OR 4.45 [1.61-12.26], p = 0.004) and liver disease (OR 2.22 [1.12-4.42], p = 0.023) were precipitators. Total costs were higher in patients with delirium (USD 30003 vs. 10977; p < 0.001).

CONCLUSION

Delirium in GI- and HPB-disease was not associated with higher age per se, but with cognitive and functional impairment. Delirium needs to be considered in younger adults with acute renal failure and/or liver disease. Clinicians should be aware about individual risk profiles, apply preventive and supportive strategies early, which may improve outcomes and lower costs.

Comparison of logistic regression and machine learning methods for predicting postoperative delirium in elderly patients: A retrospective study

AIMS

To compare the performance of logistic regression and machine learning methods in predicting postoperative delirium (POD) in elderly patients.

METHOD

This was a retrospective study of perioperative medical data from patients undergoing non-cardiac and non-neurology surgery over 65 years old from January 2014 to August 2019. Forty-six perioperative variables were used to predict POD. A traditional logistic regression and five machine learning models (Random Forest, GBM, AdaBoost, XGBoost, and a stacking ensemble model) were compared by the area under the receiver operating characteristic curve (AUC-ROC), sensitivity, specificity, and precision.

RESULTS

In total, 29,756 patients were enrolled, and the incidence of POD was 3.22% after variable screening. AUCs were 0.783 (0.765-0.8) for the logistic regression method, 0.78 for random forest, 0.76 for GBM, 0.74 for AdaBoost, 0.73 for XGBoost, and 0.77 for the stacking ensemble model. The respective sensitivities for the 6 aforementioned models were 74.2%, 72.2%, 76.8%, 63.6%, 71.6%, and 67.4%. The respective specificities for the 6 aforementioned models were 70.7%, 99.8%, 96.5%, 98.8%, 96.5%, and 96.1%. The respective precision values for the 6 aforementioned models were 7.8%, 52.3%, 55.6%, 57%, 54.5%, and 56.4%.

CONCLUSIONS

The optimal application of the logistic regression model could provide quick and convenient POD risk identification to help improve the perioperative management of surgical patients because of its better sensitivity, fewer variables, and easier interpretability than the machine learning model.

Higher Grade Glioma Increases the Risk of Postoperative Delirium: Deficient Brain Compensation Might Be a Potential Mechanism of Postoperative Delirium

Objective

The brain compensation mechanism in postoperative delirium (POD) has not been reported. We uncovered the mechanism by exploring the association between POD and glioma grades, and the relationship between preoperative brain structural and functional compensation with POD in patients with frontal glioma.

Methods

A total of 335 adult patients with glioma were included. The multivariable analysis examined the association between tumor grade and POD. Then, 20 patients with left frontal lobe glioma who had presurgical structural and functional MRI data and Montreal Cognitive Assessment (MoCA) in this cohort were analyzed. We measured the gray matter volume (GMV) and functional connectivity (FC) in patients with (n = 8) and without (n = 12) POD and healthy controls (HCs, n = 29) to detect the correlation between the structural and functional alteration and POD.

Results

The incidence of POD was 37.3%. Multivariable regression revealed that high-grade glioma had approximately six times the odds of POD. Neuroimaging data showed that compared with HC, the patients with left frontal lobe glioma showed significantly increased GMV of the right dorsal lateral prefrontal cortex (DLPFC) in the non-POD group and decreased GMV of right DLPFC in the POD group, and the POD group exhibited significantly decreased FC of right DLPFC, and the non-POD group showed the increasing tendency. Partial correlation analysis showed that GMV in contralesional DLPFC were positively correlated with preoperative neurocognition, and the GMV and FC in contralesional DLPFC were negatively correlated with POD.

Conclusions

Our findings suggested that insufficient compensation for injured brain regions involving cognition might be more vulnerable to suffering from POD.

Discharge Destinations of Delirious Patients: Findings from a Prospective Cohort Study of 27,026 Patients From a Large Health Care System

OBJECTIVES

Delirium is known to contribute to increased rates of institutionalization and mortality. The full extent of adverse outcomes, however, remains understudied. We aimed to systematically assess the discharge destinations and mortality risk in delirious patients in a large sample across all hospital services.

DESIGN

Pragmatic prospective cohort study of consecutive admissions to a large health care system.

SETTING AND PARTICIPANTS

A total of 27,026 consecutive adults (>18 years old) with length of stay of at least 24 hours in a tertiary care center from January 1 to December 31, 2014.

METHODS

Presence of delirium determined by routine delirium screening. Clinical characteristics, discharge destination, and mortality were collected. Calculation of odds ratios (ORs) with logistic regression with adjustment for age, sex, and Charlson comorbidity index (CCI).

RESULTS

Delirium was detected in 19.7% of patients (5313 of 27,026), median age of delirious patients was 56 years (25-75 interquartile range = 37-70). The electronic health record (DSM-5-based) delirium algorithm correctly identified 93.3% of delirium diagnoses made by consultation-liaison psychiatrists. Across services, the odds of delirious patients returning home was significantly reduced [OR 0.12; confidence interval (CI) 0.10-0.13; P < .001]. Rather, these patients were transferred to acute rehabilitation (OR 4.15; CI 3.78-4.55; P < .001) or nursing homes (OR 4.12; CI 3.45-4.93; P < .001). Delirious patients had a significantly increased adjusted mortality risk (OR 30.0; CI 23.2-39.4; P < .001).

CONCLUSIONS AND IMPLICATIONS

This study advances our understanding of the discharge destination across all services in adults admitted to a large hospital system. Delirium was associated with reduced odds of returning home, increased odds of discharge to a setting of higher dependency, and excess mortality independent of comorbidity, age, and sex. These findings emphasize the potentially devastating outcomes associated with delirium and highlight the need for timely diagnosis and hospital-wide management.

Effect of dexmedetomidine on postoperative delirium in patients undergoing brain tumour resections: study protocol of a randomised controlled trial

INTRODUCTION

Postoperative delirium (POD) is a common complication. The incidence of POD is about 25% in non-cardiac surgery and ranges from 10% to 30% in neurological procedures. A lot of trials show that dexmedetomidine might help to reduce the incidence of delirium in patients undergoing non-cardiac surgery. However, the impact of dexmedetomidine on POD for patients undergoing craniotomy and tumour resections remains unclear.

METHODS AND ANALYSIS

The study is a prospective, single-centre, randomised, double-blinded, paralleled-group controlled trial. Patients undergoing elective frontotemporal tumour resections will be randomly assigned to the dexmedetomidine group and the control group. After endotracheal intubation, patients in the dexmedetomidine group will be administered with a loading dose of dexmedetomidine 0.6 µg/kg in 10 min followed by continuous infusion at a rate of 0.4 µg/kg/hour until the start of dural closure. In the control group, patients will receive the identical volume of normal saline in the same setting. The primary outcome will be the cumulative incidence of POD within 5 days. The delirium assessment will be performed by using the confusion assessment method in the first 5 consecutive days after surgery. Secondary outcomes include the pain severity assessed by Numerical Rating Scale pain score, quality of postoperative sleep assessed by the Richards Campbell sleep questionnaire and postoperative quality of recovery from anaesthesia by the Postoperative Quality Recovery Scale.

ETHICS AND DISSEMINATION

The protocol (V.1.0, 10 November 2020) has been approved by the Ethics Review Committee of the Chinese Clinical Trial Registry (number ChiECRCT-20200436). The findings of the study will be disseminated in a peer-reviewed journal and at a scientific conference.

TRIAL REGISTRATION NUMBER

NCT04674241.

Evaluation and Management of Delirium

Delirium, sometimes referred to as encephalopathy, is an acute confusional state that is both common in hospitalized patients and associated with poor outcomes. For patients, families, and caregivers, delirium can be a traumatic experience. While delirium is one of the most common diagnoses encountered by the consulting neurologist, the majority of the time it will have been previously unrecognized as such by the care team. Neurologic syndromes such as dementia or aphasia can either be misdiagnosed as delirium or may coexist with it, necessitating careful neurologic assessment. Once the diagnosis of delirium has been established, a careful evaluation for predisposing and precipitating factors can help uncover modifiable contributors, which should be addressed as part of a multicomponent, primarily nonpharmacologic intervention. Importantly, delirium management, which begins with comprehensive prevention, should emphasize the humanity of the delirious patient and the challenges of caring for this vulnerable population. When considered, delirium represents an important opportunity for the neurologist to substantially enhance patient care.

Music to prevent deliriUm during neuroSurgerY (MUSYC) Clinical trial: a study protocol for a randomised controlled trial

INTRODUCTION

Delirium is a neurocognitive disorder characterised by an acute and temporary decline of mental status affecting attention, awareness, cognition, language and visuospatial ability. The underlying pathophysiology is driven by neuroinflammation and cellular oxidative stress.Delirium is a serious complication following neurosurgical procedures with a reported incidence varying between 4% and 44% and has been associated with increased length of hospital stay, increased amount of reoperations, increased costs and mortality.Perioperative music has been reported to reduce preoperative anxiety, postoperative pain and opioid usage, and attenuates stress response caused by surgery. We hypothesize that this beneficial effect of music on a combination of delirium eliciting factors might reduce delirium incidence following neurosurgery and subsequently improve clinical outcomes.

METHODS

This protocol concerns a single-centred prospective randomised controlled trial with 6 months follow-up. All adult patients undergoing a craniotomy at the Erasmus Medical Center in Rotterdam are eligible. The music group will receive recorded music through an overear headphone before, during and after surgery until postoperative day 3. Patients can choose from music playlists, offered based on music importance questionnaires administered at baseline. The control group will receive standard of clinical careDelirium is assessed by the Delirium Observation Scale and confirmed by a delirium-expert psychiatrist according to the DSM-5 criteria. Risk factors correlated with the onset of delirium, such as cognitive function at baseline, preoperative anxiety, perioperative medication use, depth of anaesthesia and postoperative pain, and delirium-related health outcomes such as length of stay, daily function, quality of life (ie, EQ-5D, EORTC questionnaires), costs and cost-effectiveness are collected.

ETHICS AND DISSEMINATION

This study is being conducted in accordance with the Declaration of Helsinki. The Medical Ethics Review Board of Erasmus University Medical Center Rotterdam, The Netherlands, approved this protocol. Results will be disseminated via peer-reviewed scientific journals and conference presentations.

TRIAL REGISTRATION NUMBERS

NL8503 and NCT04649450.

Reflections on dexmedetomidine as an optimum therapy for emergence delirium in the elderly with emergency abdominal surgery

Emergence delirium (ED) is a common complication in elderly patients in post post-anesthesia care units (PACU), To our knowledge, there is currently no specific treatment for ED in the elderly, especially for patients combined with vital organs dysfunction. This article described an elderly patient with ED was successfully treated with dexmedetomidine. Although dexmedetomidine has been widely used in recent years, there are few articles on the administration of dexmedetomidine in PACU. The purpose of this paper is to review the literature and analyze related hazardous factors for ED in the elderly with complications of emergency abdominal surgery and angiocardiopathy, and to further confirm and explain the effectiveness and validation of dexmedetomidine as a rescue therapy in PACU. Finally, we look forward to more samples being collected to persuasively prove our opinion in this case.

Delirium in neurosurgery: a systematic review and meta-analysis

Delirium is a frequent occurring complication in surgical patients. Nevertheless, a scientific work-up of the clinical relevance of delirium after intracranial surgery is lacking. We conducted a systematic review (CRD42020166656) to evaluate the current diagnostic work-up, incidence, risk factors and health outcomes of delirium in this population. Five databases (Embase, Medline, Web of Science, PsycINFO, Cochrane Central) were searched from inception through March 31st, 2021. Twenty-four studies (5589 patients) were included for qualitative analysis and twenty-one studies for quantitative analysis (5083 patients). Validated delirium screening tools were used in 70% of the studies, consisting of the Confusion Assessment Method (intensive care unit) (45%), Delirium Observation Screening Scale (5%), Intensive Care Delirium Screening Checklist (10%), Neelon and Champagne Confusion Scale (5%) and Nursing Delirium Screening Scale (5%). Incidence of post-operative delirium after intracranial surgery was 19%, ranging from 12 to 26% caused by variation in clinical features and delirium assessment methods. Meta-regression for age and gender did not show a correlation with delirium. We present an overview of risk factors and health outcomes associated with the onset of delirium. Our review highlights the need of future research on delirium in neurosurgery, which should focus on optimizing diagnosis and assessing prognostic significance and management.

Management of post-operative delirium following stereoelectroencephalography electrode placement for drug resistant epilepsy: Lessons learned from two case reports

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Post-operative delirium poses unique challenges in neurosurgical patients.

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Substance use is a modifiable risk factor for post-operative delirium after SEEG.

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SEEG patients have increased risk of harm when experiencing post-operative delirium.

Post-operative delirium (POD) represents a unique challenge in the care of any surgical patient but is especially challenging in neurosurgical inpatient management due to a host of potentially significant predisposing factors. Patients undergoing stereoencephalography (SEEG) for diagnosis of drug resistant epilepsy are at unique risk due to safety concerns, yet POD has been underdiscussed in this population. Patients should be counseled pre-operatively about their risk and subsequent steps be taken post-operatively. We present two cases of POD status-post SEEG and propose a mechanism by which future post-operative care be coordinated by the physician, patient, and patient’s family.

Death in delirious palliative-care patients occurs irrespective of age: A prospective, observational cohort study of 229 delirious palliative-care patients

Objectives

Patients with terminal illness are at high risk of developing delirium, in particular, those with multiple predisposing and precipitating risk factors. Delirium in palliative care is largely under-researched, and few studies have systematically assessed key aspects of delirium in elderly, palliative-care patients.

Methods

In this prospective, observational cohort study at a tertiary care center, 229 delirious palliative-care patients stratified by age: <65 (N = 105) and ≥65 years (N = 124), were analyzed with logistic regression models to identify associations with respect to predisposing and precipitating factors.

Results

In 88% of the patients, the underlying diagnosis was cancer. Mortality rate and median time to death did not differ significantly between the two age groups. No inter-group differences were detected with respect to gender, care requirements, length of hospital stay, or medical costs. In patients ≥65 years, exclusively predisposing factors were relevant for delirium, including hearing impairment [odds ratio (OR) 3.64; confidence interval (CI) 1.90–6.99; P < 0.001], hypertension (OR 3.57; CI 1.84–6.92; P < 0.001), and chronic kidney disease (OR 4.84; CI 1.19–19.72; P = 0.028). In contrast, in patients <65 years, only precipitating factors were relevant for delirium, including cerebral edema (OR 0.02; CI 0.01–0.43; P = 0.012).

Significance of results

The results of this study demonstrate that death in delirious palliative-care patients occurs irrespective of age. The multifactorial nature and adverse outcomes of delirium across all age in these patients require clinical recognition. Potentially reversible factors should be detected early to prevent or mitigate delirium and its poor survival outcomes.

Predisposing and precipitating risk factors for delirium in palliative care patients

Objective

Delirium is a common complication in palliative care patients, especially in the terminal phase of the illness. To date, evidence regarding risk factors and prognostic outcomes of delirium in this vulnerable population remains sparse.

Method

In this prospective observational cohort study at a tertiary care center, 410 palliative care patients were included. Simple and multiple logistic regression models were used to identify associations between predisposing and precipitating factors and delirium in palliative care patients.

Results

The prevalence of delirium in this palliative care cohort was 55.9% and reached 93% in the terminally ill. Delirium was associated with prolonged hospitalization (p < 0.001), increased care requirements (p < 0.001) and health care costs (p < 0.001), requirement for institutionalization (OR 0.11; CI 0.069–0.171; p < 0.001), and increased mortality (OR 18.29; CI 8.918–37.530; p < 0.001). Predisposing factors for delirium were male gender (OR 2.19; CI 1.251–3.841; p < 0.01), frailty (OR 15.28; CI 5.885–39.665; p < 0.001), hearing (OR 3.52; CI 1.721–7.210; p < 0.001), visual impairment (OR 3.15; CI 1.765–5.607; p < 0.001), and neoplastic brain disease (OR 3.63; CI 1.033–12.771; p < 0.05). Precipitating factors for delirium were acute renal failure (OR 6.79; CI 1.062–43.405; p < 0.05) and pressure sores (OR 3.66; CI 1.102–12.149; p < 0.05).

Significance of results

Our study identified several predisposing and precipitating risk factors for delirium in palliative care patients, some of which can be targeted early and modified to reduce symptom burden.

Predisposing and precipitating factors for delirium in neurology: a prospective cohort study of 1487 patients

INTRODUCTION

Predisposing and precipitating factors for delirium are well known; however, their interaction and impact on delirium in neurological patients remains largely unknown. Therefore, those factors were evaluated in hospitalized patients with neurological disorders.

METHODS

In this prospective cohort study, 1487 neurological patients were included, 356 patients with delirium and 1131 without delirium. Relevant neurological- and medical-related clusters were assessed with multiple regression analyses, prediction models, and cluster analysis evaluating their association with delirium.

RESULTS

The 1-year incidence of delirium in this cohort was 23.9%. Delirium developed in 31% of patients with stroke, in 39.5% with epilepsy, and in 58.4% with ICH. The most relevant predisposing factors were substance-use disorders (OR 4.24, 2.28-7.78, p < 0.001), advanced age (OR 3.44, CI 2.40-4.92, p < 0.001), and neurodegenerative disorders (OR 2.58, CI 1.47-4.54, p = 0.001). The most relevant precipitating factors were meningitis (OR 21.52, CI 1.22-379.83, p = 0.036), acute renal failure (OR 10.01, CI 1.13-88.73, p = 0.039), and intracranial hemorrhage (OR 3.62, CI 2.08-6.30, p < 0.001). Delirious patients were hospitalized 6 days longer, had higher in-hospital mortality, and were discharged more often to nursing homes and rehabilitation. Best predictor for delirium was the coexistence of advanced age with epilepsy (58.3%, p < 0.001), while patients aged < 65 years without epilepsy and stroke rarely developed delirium (5.1%, p < 0.001).

CONCLUSIONS

Delirium is common in elder neurological patients and associated with worse outcome. Primary cerebral conditions most frequently precipitate delirium in neurology. Neurologists are advised to monitor symptoms of delirium in the presence of risk factors to enable both timely diagnostic work-up and management of delirium.