Rivastigmine in the treatment of delirium in older people: a pilot study

Pharmacologic Treatment Strategies for Delirium in Hospitalized Adults: Past, Present, and Future

Despite the use of multidomain prevention strategies, delirium still frequently occurs in hospitalized adults. With delirium often associated with undesirable symptoms and deleterious outcomes, including cognitive decline, treatment is important. Risk-factor reduction and the protocolized use of multidomain, nonpharmacologic bundles remain the mainstay of delirium treatment. There is a current lack of strong evidence to suggest any pharmacologic intervention to treat delirium will help resolve it faster, reduce its symptoms (other than agitation), facilitate hospital throughput, or improve post-hospital outcomes including long-term cognitive function. With the exception of dexmedetomidine as a treatment of severe delirium-associated agitation in the ICU, current practice guidelines do not recommend the routine use of any pharmacologic intervention to treat delirium in any hospital population. Future research should focus on identifying and evaluating new pharmacologic delirium treatment interventions and addressing key challenges and gaps surrounding delirium treatment research.

The impact of rivastigmine on post-surgical delirium and cognitive impairment; a randomized clinical trial

BACKGROUND

Delirium is an acute and transient disorder of brain function that often occurs in post-surgical patients. Rivastigmine is a cholinesterase inhibitor drug that has been proposed as an adjuvant drug in recent years, still, despite significant theoretical evidence, few clinical studies have been performed on its impact on delirium.

AIM

Due to the widespread use of cholinesterase inhibitors in pediatric and adult surgery, the present study aims to investigate the impact of Rivastigmine as a cholinesterase inhibitor on delirium after radical surgery.

METHODS

In this randomized double-blind clinical trial, a hundred recruited patients were randomly assigned to either Rivastigmine (n = 50) or placebo (n = 50) groups, and we measured post-operative impact on delirium, by Confusion Assessment Method (CAM) score, and cognitive impairment, by the Mini-Mental State Examination (MMSE). Our univariate and multivariate logistical regression models assessed this hypothesized impact.

RESULTS

Treatment with Rivastigmine was significantly associated with reduced day one post-op delirium, as measured by CAM score (Odds Ratio (OR) = 0.35, 95% Confidence Interval (CI) 0.11 to 0.97, p = 0.05), and cognitive impairment, as measured by MMSE (OR = 0.25, 95% CI 0.1 to 0.59, p = 0.0022). These associations became stronger after controlling for age, blood loss, and post-op blood sodium levels: Delirium (OR = 0.23, 95% CI 0.05 to 0.92, p = 0.05), cognitive impairment (OR = 0.12, 95% CI 0.03 to 0.42, p = 0.000178).

CONCLUSION

The significant result of our randomized clinical trial is that pre-op Rivastigmine treatment may be associated with a substantial drop in patients experiencing post-op delirium and post-op cognitive impairment.

Pharmacologic treatment of delirium symptoms: A systematic review

OBJECTIVE

We conducted an updated, comprehensive, and contemporary systematic review to examine the efficacy of existing pharmacologic agents employed for management of delirium symptoms among hospitalized adults.

METHODS

Searches of PubMed, Scopus, Embase, and Cochrane Library databases from inception to May 2021 were performed to identify studies investigating efficacy of pharmacologic agents for management of delirium.

RESULTS

Of 11,424 articles obtained from searches, a total of 33 articles (N = 3030 participants) of randomized or non-randomized trials, in which pharmacologic treatment was compared to active comparator, placebo, or no treatment, met all criteria and were included in this review. Medications used for management of delirium symptoms included antipsychotic medications (N = 27), alpha-2 agonists (N = 5), benzodiazepines (N = 2), antidepressants (n = 1), acetylcholinesterase inhibitors (N = 2), melatonin (N = 2), opioids (N = 1), and antiemetics (N = 2). Despite somewhat mixed findings and a relative lack of high-quality trials, it appears that antipsychotic medications (e.g., haloperidol, olanzapine, risperidone, or quetiapine) and dexmedetomidine have the potential to improve delirium outcomes.

CONCLUSIONS

Pharmacologic agents can reduce delirium symptoms (e.g., agitation) in some hospitalized patients. Additional double-blinded, randomized, placebo-controlled clinical trials are critically needed to investigate the efficacy of pharmacologic agents for diverse hospitalized populations (e.g., post-surgical patients, patients at the end-of-life, or in intensive care units).

Drug therapy for delirium in terminally ill adults

BACKGROUND

Delirium is a syndrome characterised by an acute disturbance of attention and awareness which develops over a short time period and fluctuates in severity over the course of the day. It is commonly experienced during inpatient admission in the terminal phase of illness. It can cause symptoms such as agitation and hallucinations and is distressing for terminally ill people, their families and staff. Delirium may arise from any number of causes and treatment should aim to address these causes. When this is not possible, or treatment is unsuccessful, drug therapy to manage the symptoms may become necessary. This is the second update of the review first published in 2004.

OBJECTIVES

To evaluate the effectiveness and safety of drug therapies to manage delirium symptoms in terminally ill adults.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL and PsycINFO from inception to July 2019, reference lists of retrieved papers, and online trial registries.

SELECTION CRITERIA

We included randomised controlled trials of drug therapies in any dose by any route, compared to another drug therapy, a non-pharmacological approach, placebo, standard care or wait-list control, for the management of delirium symptoms in terminally ill adults (18 years or older).

DATA COLLECTION AND ANALYSIS

We independently screened citations, extracted data and assessed risk of bias. Primary outcomes were delirium symptoms; agitation score; adverse events. Secondary outcomes were: use of rescue medication; cognitive status; survival. We applied the GRADE approach to assess the overall quality of the evidence for each outcome and we include eight 'Summary of findings' tables.

MAIN RESULTS

We included four studies (three new to this update), with 399 participants. Most participants had advanced cancer or advanced AIDS, and mild- to moderate-severity delirium. Meta-analysis was not possible because no two studies examined the same comparison. Each study was at high risk of bias for at least one criterion. Most evidence was low to very low quality, downgraded due to very serious study limitations, imprecision or because there were so few data. Most studies reported delirium symptoms; two reported agitation scores; three reported adverse events with data on extrapyramidal effects; and none reported serious adverse events. 1. Haloperidol versus placebo There may be little to no difference between placebo and haloperidol in delirium symptoms within 24 hours (mean difference (MD) 0.34, 95% confidence interval (CI) -0.07 to 0.75; 133 participants). Haloperidol may slightly worsen delirium symptoms compared with placebo at 48 hours (MD 0.49, 95% CI 0.10 to 0.88; 123 participants with mild- to moderate-severity delirium). Haloperidol may reduce agitation slightly compared with placebo between 24 and 48 hours (MD -0.14, 95% -0.28 to -0.00; 123 participants with mild- to moderate-severity delirium). Haloperidol probably increases extrapyramidal adverse effects compared with placebo (MD 0.79, 95% CI 0.17 to 1.41; 123 participants with mild- to moderate-severity delirium). 2. Haloperidol versus risperidone There may be little to no difference in delirium symptoms with haloperidol compared with risperidone within 24 hours (MD -0.42, 95% CI -0.90 to 0.06; 126 participants) or 48 hours (MD -0.36, 95% CI -0.92 to 0.20; 106 participants with mild- to moderate-severity delirium). Agitation scores and adverse events were not reported for this comparison. 3. Haloperidol versus olanzapine We are uncertain whether haloperidol reduces delirium symptoms compared with olanzapine within 24 hours (MD 2.36, 95% CI -0.75 to 5.47; 28 participants) or 48 hours (MD 1.90, 95% CI -1.50 to 5.30, 24 participants). Agitation scores and adverse events were not reported for this comparison. 4. Risperidone versus placebo Risperidone may slightly worsen delirium symptoms compared with placebo within 24 hours (MD 0.76, 95% CI 0.30 to 1.22; 129 participants); and at 48 hours (MD 0.85, 95% CI 0.32 to 1.38; 111 participants with mild- to moderate-severity delirium). There may be little to no difference in agitation with risperidone compared with placebo between 24 and 48 hours (MD -0.05, 95% CI -0.19 to 0.09; 111 participants with mild- to moderate-severity delirium). Risperidone may increase extrapyramidal adverse effects compared with placebo (MD 0.73 95% CI 0.09 to 1.37; 111 participants with mild- to moderate-severity delirium). 5. Lorazepam plus haloperidol versus placebo plus haloperidol We are uncertain whether lorazepam plus haloperidol compared with placebo plus haloperidol improves delirium symptoms within 24 hours (MD 2.10, 95% CI -1.00 to 5.20; 50 participants with moderate to severe delirium), reduces agitation within 24 hours (MD 1.90, 95% CI 0.90 to 2.80; 52 participants), or increases adverse events (RR 0.70, 95% CI -0.19 to 2.63; 31 participants with moderate to severe delirium). 6. Haloperidol versus chlorpromazine We are uncertain whether haloperidol reduces delirium symptoms compared with chlorpromazine at 48 hours (MD 0.37, 95% CI -4.58 to 5.32; 24 participants). Agitation scores were not reported. We are uncertain whether haloperidol increases adverse events compared with chlorpromazine (MD 0.46, 95% CI -4.22 to 5.14; 24 participants). 7. Haloperidol versus lorazepam We are uncertain whether haloperidol reduces delirium symptoms compared with lorazepam at 48 hours (MD -4.88, 95% CI -9.70 to 0.06; 17 participants). Agitation scores were not reported. We are uncertain whether haloperidol increases adverse events compared with lorazepam (MD -6.66, 95% CI -14.85 to 1.53; 17 participants). 8. Lorazepam versus chlorpromazine We are uncertain whether lorazepam reduces delirium symptoms compared with chlorpromazine at 48 hours (MD 5.25, 95% CI 0.38 to 10.12; 19 participants), or increases adverse events (MD 7.12, 95% CI 1.08 to 15.32; 18 participants). Agitation scores were not reported.

SECONDARY OUTCOMES

use of rescue medication, cognitive impairment, survival There were insufficient data to draw conclusions or assess GRADE.

AUTHORS' CONCLUSIONS

We found no high-quality evidence to support or refute the use of drug therapy for delirium symptoms in terminally ill adults. We found low-quality evidence that risperidone or haloperidol may slightly worsen delirium symptoms of mild to moderate severity for terminally ill people compared with placebo. We found moderate- to low-quality evidence that haloperidol and risperidone may slightly increase extrapyramidal adverse events for people with mild- to moderate-severity delirium. Given the small number of studies and participants on which current evidence is based, further research is essential.

Interventions for preventing delirium in older people in institutional long-term care

BACKGROUND

Delirium is a common and distressing mental disorder. It is often caused by a combination of stressor events in susceptible people, particularly older people living with frailty and dementia. Adults living in institutional long-term care (LTC) are at particularly high risk of delirium. An episode of delirium increases risks of admission to hospital, development or worsening of dementia and death. Multicomponent interventions can reduce the incidence of delirium by a third in the hospital setting. However, it is currently unclear whether interventions to prevent delirium in LTC are effective. This is an update of a Cochrane Review first published in 2014.

OBJECTIVES

To assess the effectiveness of interventions for preventing delirium in older people in institutional long-term care settings.

SEARCH METHODS

We searched ALOIS (www.medicine.ox.ac.uk/alois), the Cochrane Dementia and Cognitive Improvement Group (CDCIG) 's Specialised Register of dementia trials (dementia.cochrane.org/our-trials-register), to 27 February 2019. The search was sufficiently sensitive to identify all studies relating to delirium. We ran additional separate searches in the Cochrane Central Register of Controlled Trials (CENTRAL), major healthcare databases, trial registers and grey literature sources to ensure that the search was comprehensive.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and cluster-randomised controlled trials (cluster-RCTs) of single and multicomponent, non-pharmacological and pharmacological interventions for preventing delirium in older people (aged 65 years and over) in permanent LTC residence.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Primary outcomes were prevalence, incidence and severity of delirium; and mortality. Secondary outcomes included falls, hospital admissions and other adverse events; cognitive function; new diagnoses of dementia; activities of daily living; quality of life; and cost-related outcomes. We used risk ratios (RRs) as measures of treatment effect for dichotomous outcomes, hazard ratios (HR) for time-to-event outcomes and mean difference (MD) for continuous outcomes. For each outcome, we assessed the overall certainty of the evidence using GRADE methods.

MAIN RESULTS

We included three trials with 3851 participants. All three were cluster-RCTs. Two of the trials were of complex, single-component, non-pharmacological interventions and one trial was a feasibility trial of a complex, multicomponent, non-pharmacological intervention. Risk of bias ratings were mixed across the three trials. Due to the heterogeneous nature of the interventions, we did not combine the results statistically, but produced a narrative summary.It was not possible to determine the effect of a hydration-based intervention on delirium incidence (RR 0.85, 95% confidence interval (CI) 0.18 to 4.00; 1 study, 98 participants; very low-certainty evidence downgraded for risk of bias and very serious imprecision). This study did not assess delirium prevalence, severity or mortality.The introduction of a computerised system to identify medications that may contribute to delirium risk and trigger a medication review was probably associated with a reduction in delirium incidence (12-month HR 0.42, CI 0.34 to 0.51; 1 study, 7311 participant-months; moderate-certainty evidence downgraded for risk of bias) but probably had little or no effect on mortality (HR 0.88, CI 0.66 to 1.17; 1 study, 9412 participant-months; moderate-certainty evidence downgraded for imprecision), hospital admissions (HR 0.89, CI 0.72 to 1.10; 1 study, 7599 participant-months; moderate-certainty evidence downgraded for imprecision) or falls (HR 1.03, CI 0.92 to 1.15; 1 study, 2275 participant-months; low-certainty evidence downgraded for imprecision and risk of bias). Delirium prevalence and severity were not assessed.In the enhanced educational intervention study, aimed at changing practice to address key delirium risk factors, it was not possible to determine the effect of the intervention on delirium incidence (RR 0.62, 95% CI 0.16 to 2.39; 1 study, 137 resident months; very low-certainty evidence downgraded for risk of bias and serious imprecision) or delirium prevalence (RR 0.57, 95% CI 0.15 to 2.19; 1 study, 160 participants; very low-certainty evidence downgraded for risk of bias and serious imprecision). There was probably little or no effect on mortality (RR 0.82, CI 0.50 to 1.34; 1 study, 215 participants; moderate-certainty evidence downgraded for imprecision). The intervention was probably associated with a reduction in hospital admissions (RR 0.67, CI 0.57 to 0.79; 1 study, 494 participants; moderate-certainty evidence downgraded due to indirectness).

AUTHORS' CONCLUSIONS

Our review identified limited evidence on interventions for preventing delirium in older people in LTC. A software-based intervention to identify medications that could contribute to delirium risk and trigger a pharmacist-led medication review, probably reduces incidence of delirium in older people in institutional LTC. This is based on one large RCT in the US and may not be practical in other countries or settings which do not have comparable information technology services available in care homes. In the educational intervention aimed at identifying risk factors for delirium and developing bespoke solutions within care homes, it was not possible to determine the effect of the intervention on delirium incidence, prevalence or mortality. This evidence is based on a small feasibility trial. Our review identified three ongoing trials of multicomponent delirium prevention interventions. We identified no trials of pharmacological agents. Future trials of multicomponent non-pharmacological delirium prevention interventions for older people in LTC are needed to help inform the provision of evidence-based care for this vulnerable group.

Cholinesterase inhibitors for the treatment of delirium in non-ICU settings

BACKGROUND

Delirium is a common clinical syndrome defined as alterations in attention with an additional disturbance in cognition or perception, which develop over a short period of time and tend to fluctuate during the course of the episode. Delirium is commonly treated in hospitals or community settings and is often associated with multiple adverse outcomes such as increased cost, morbidity, and even mortality. The first-line intervention involves a multicomponent non-pharmacological approach that includes ensuring effective communication and reorientation in addition to providing reassurance or a suitable care environment. There are currently no drugs approved specifically for the treatment of delirium. Clinically, however, various medications are employed to provide symptomatic relief, such as antipsychotic medications and cholinesterase inhibitors, among others.

OBJECTIVES

To evaluate the effectiveness and safety of cholinesterase inhibitors for treating people with established delirium in a non-intensive care unit (ICU) setting.

SEARCH METHODS

We searched ALOIS, which is the Cochrane Dementia and Cognitive Improvement Group's Specialised Register, on 26 October 2017. We also cross-checked the reference lists of included studies to identify any potentially eligible trials.

SELECTION CRITERIA

We included randomised controlled trials, published or unpublished, reported in English or Chinese, which compared cholinesterase inhibitors to placebo or other drugs intended to treat people with established delirium in a non-ICU setting.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. The primary outcomes were duration of delirium, severity of delirium, and adverse events. The secondary outcomes were use of rescue medications, persistent cognitive impairment, length of hospitalisation, institutionalisation, mortality, cost of intervention, leaving the study early, and quality of life. For dichotomous outcomes, we calculated the risk ratio (RR) with 95% confidence intervals (CIs); for continuous outcomes we calculated the mean difference (MD) with 95% CIs. We assessed the quality of evidence using GRADE to generate a 'Summary of findings' table.

MAIN RESULTS

We included one study involving 15 participants from the UK. The included participants were diagnosed with delirium based on the Confusion Assessment Method (CAM) criteria. Eight males and seven females were included, with a mean age of 82.5 years. Seven of the 15 participants had comorbid dementia at baseline. The risk of bias was low in all domains.The study compared rivastigmine with placebo. We did not find any clear differences between the two groups in terms of duration of delirium (MD -3.6, 95% CI -15.6 to 8.4), adverse events (nausea, RR 0.30, 95% CI 0.01 to 6.29), use of rescue medications (RR 0.13, 95% CI 0.01 to 2.1), mortality (RR 0.10, 95% CI 0.01 to 1.56), and leaving the study early (RR 0.88, 95% CI 0.07 to 11.54). Evidence was not available regarding the severity of delirium, persistent cognitive impairment, length of hospitalisation, cost of intervention, or other predefined secondary outcomes.The quality of evidence is low due to the very small sample size.

AUTHORS' CONCLUSIONS

There is insufficient evidence to support or refute the use of cholinesterase inhibitors for the treatment of delirium in non-ICU settings. No clear benefits or harms associated with cholinesterase inhibitors were observed when compared with placebo due to the lack of data. More trials are required.

Acetylcholinesterase Activity Measurement and Clinical Features of Delirium

AIMS

Cholinergic deficiency is commonly implicated in the pathophysiology of delirium. We aimed to investigate the relationship between directly measured serum acetylcholinesterase (AChE) activity and (1) clinical features of delirium and (2) outcomes among older hospital patients with delirium.

METHODS

Hospitalised patients with delirium were recruited, and delirium motor subtype, severity and duration of delirium were measured. Serum AChE activity was measured using a colorimetric assay.

RESULTS

The mean AChE activity for the whole sample was 2.46 μmol/μL/min (standard deviation 1.75). Higher AChE activity was associated with increased likelihood of hypoactive delirium rather than the hyperactive or mixed subtype (odds ratio 1.98, 95% confidence interval 1.10-3.59).

CONCLUSION

Higher AChE activity was associated with hypoactive delirium but did not predict outcomes. Simple enhancement of cholinergic neurotransmission may not be sufficient to treat delirium.

Delirium in the elderly: A systematic review of pharmacological and non-pharmacological treatments

Delirium is a common disorder associated with poor prognosis, especially in the elderly. The impact of different treatment approaches for delirium on morbimortality and long-term welfare is not completely understood.

OBJECTIVE

To determine the efficacy of pharmacological and non-pharmacological treatments in elderly patients with delirium.

METHODS

This systematic review compared pharmacological and non-pharmacological treatments in patients over 60 years old with delirium. Databases used were: MEDLINE (PubMed), EMBASE, Cochrane CENTRAL and LILACS from inception to January 6^th, 2016.

RESULTS

A total of ten articles were selected. The six non-pharmacological intervention studies showed no impact on duration of delirium, mortality or institutionalization, but a decrease in severity of delirium and improvement in medium-term cognitive function were observed. The most commonly used interventions were temporal-spatial orientation, orientation to self and others, early mobilization and sleep hygiene. The four studies with pharmacological interventions found that rivastigmine reduced the duration of delirium, improved cognitive function and reduced caregiver burden; olanzapine and haloperidol decreased the severity of delirium; droperidol reduced length of hospitalization and improved delirium remission rate.

CONCLUSION

Although the pharmacological approach has been used in the treatment of delirium among elderly, there have been few studies assessing its efficacy, involving a small number of patients. However, the improvements in delirium duration and severity suggest these drugs are effective in treating the condition. Once delirium has developed, non-pharmacological treatment seems less effective in controlling symptoms, and there is a lack of studies describing different non-pharmacological interventions.

Delirium in critically ill patients

Delirium is common in critically ill patients and associated with increased length of stay in the intensive care unit (ICU) and long-term cognitive impairment. The pathophysiology of delirium has been explained by neuroinflammation, an aberrant stress response, neurotransmitter imbalances, and neuronal network alterations. Delirium develops mostly in vulnerable patients (e.g., elderly and cognitively impaired) in the throes of a critical illness. Delirium is by definition due to an underlying condition and can be identified at ICU admission using prediction models. Treatment of delirium can be improved with frequent monitoring, as early detection and subsequent treatment of the underlying condition can improve outcome. Cautious use or avoidance of benzodiazepines may reduce the likelihood of developing delirium. Nonpharmacologic strategies with early mobilization, reducing causes for sleep deprivation, and reorientation measures may be effective in the prevention of delirium. Antipsychotics are effective in treating hallucinations and agitation, but do not reduce the duration of delirium. Combined pain, agitation, and delirium protocols seem to improve the outcome of critically ill patients and may reduce delirium incidence.

Acetylcholinesterase Inhibitors for Delirium in Older Adults

OBJECTIVES

The aim of this systematic review is to identify published randomized controlled trials (RCTs) that evaluated the use of acetylcholinesterase inhibitors for delirium in older adults (≥60 years).

METHODS

A literature search was conducted of PubMed, MEDLINE, EMBASE, PsycINFO, and Cochrane collaboration databases for RCTs in any language that evaluated the use of acetylcholinesterase inhibitors for delirium in older adults (≥60 years). Also, bibliographic databases of the published articles were searched for additional studies.

RESULTS

A total of 7 RCTs that evaluated the use of acetylcholinesterase inhibitors for delirium in older adults (≥60 years) were identified. In 5 of the 7 studies, there was no benefit for the acetylcholinesterase inhibitor in either the prevention or the management of delirium. In one study, there was a trend toward benefit for the active drug group on the incidence of delirium and the length of hospital stay, but both outcomes did not attain statistical significance. One study found a longer duration of delirium and a longer length of hospital stay in the active drug group when compared to the placebo group. The acetylcholinesterase inhibitors were well tolerated in 4 of the 7 studies. In 1 study, the mortality rate was found to be almost 3 times higher in the group receiving haloperidol and rivastigmine when compared to the group receiving haloperidol and placebo.

CONCLUSION

Current evidence does not suggest efficacy of acetylcholinesterase inhibitors for the prevention or management of delirium in older adults.

Interventions for preventing delirium in hospitalised non-ICU patients

BACKGROUND

Delirium is a common mental disorder, which is distressing and has serious adverse outcomes in hospitalised patients. Prevention of delirium is desirable from the perspective of patients and carers, and healthcare providers. It is currently unclear, however, whether interventions for preventing delirium are effective.

OBJECTIVES

To assess the effectiveness of interventions for preventing delirium in hospitalised non-Intensive Care Unit (ICU) patients.

SEARCH METHODS

We searched ALOIS - the Cochrane Dementia and Cognitive Improvement Group's Specialized Register on 4 December 2015 for all randomised studies on preventing delirium. We also searched MEDLINE (Ovid SP), EMBASE (Ovid SP), PsycINFO (Ovid SP), Central (The Cochrane Library), CINAHL (EBSCOhost), LILACS (BIREME), Web of Science core collection (ISI Web of Science), ClinicalTrials.gov and the WHO meta register of trials, ICTRP.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of single and multi- component non-pharmacological and pharmacological interventions for preventing delirium in hospitalised non-ICU patients.

DATA COLLECTION AND ANALYSIS

Two review authors examined titles and abstracts of citations identified by the search for eligibility and extracted data independently, with any disagreements settled by consensus. The primary outcome was incidence of delirium; secondary outcomes included duration and severity of delirium, institutional care at discharge, quality of life and healthcare costs. We used risk ratios (RRs) as measures of treatment effect for dichotomous outcomes; and between group mean differences and standard deviations for continuous outcomes.

MAIN RESULTS

We included 39 trials that recruited 16,082 participants, assessing 22 different interventions or comparisons. Fourteen trials were placebo-controlled, 15 evaluated a delirium prevention intervention against usual care, and 10 compared two different interventions. Thirty-two studies were conducted in patients undergoing surgery, the majority in orthopaedic settings. Seven studies were conducted in general medical or geriatric medicine settings.We found multi-component interventions reduced the incidence of delirium compared to usual care (RR 0.69, 95% CI 0.59 to 0.81; seven studies; 1950 participants; moderate-quality evidence). Effect sizes were similar in medical (RR 0.63, 95% CI 0.43 to 0.92; four studies; 1365 participants) and surgical settings (RR 0.71, 95% CI 0.59 to 0.85; three studies; 585 participants). In the subgroup of patients with pre-existing dementia, the effect of multi-component interventions remains uncertain (RR 0.90, 95% CI 0.59 to 1.36; one study, 50 participants; low-quality evidence).There is no clear evidence that cholinesterase inhibitors are effective in preventing delirium compared to placebo (RR 0.68, 95% CI, 0.17 to 2.62; two studies, 113 participants; very low-quality evidence).Three trials provide no clear evidence of an effect of antipsychotic medications as a group on the incidence of delirium (RR 0.73, 95% CI, 0.33 to 1.59; 916 participants; very low-quality evidence). In a pre-planned subgroup analysis there was no evidence for effectiveness of a typical antipsychotic (haloperidol) (RR 1.05, 95% CI 0.69 to 1.60; two studies; 516 participants, low-quality evidence). However, delirium incidence was lower (RR 0.36, 95% CI 0.24 to 0.52; one study; 400 participants, moderate-quality evidence) for patients treated with an atypical antipsychotic (olanzapine) compared to placebo (moderate-quality evidence).There is no clear evidence that melatonin or melatonin agonists reduce delirium incidence compared to placebo (RR 0.41, 95% CI 0.09 to 1.89; three studies, 529 participants; low-quality evidence).There is moderate-quality evidence that Bispectral Index (BIS)-guided anaesthesia reduces the incidence of delirium compared to BIS-blinded anaesthesia or clinical judgement (RR 0.71, 95% CI 0.60 to 0.85; two studies; 2057 participants).It is not possible to generate robust evidence statements for a range of additional pharmacological and anaesthetic interventions due to small numbers of trials, of variable methodological quality.

AUTHORS' CONCLUSIONS

There is strong evidence supporting multi-component interventions to prevent delirium in hospitalised patients. There is no clear evidence that cholinesterase inhibitors, antipsychotic medication or melatonin reduce the incidence of delirium. Using the Bispectral Index to monitor and control depth of anaesthesia reduces the incidence of postoperative delirium. The role of drugs and other anaesthetic techniques to prevent delirium remains uncertain.

Muscarinic M1 receptors modulate endotoxemia-induced loss of synaptic plasticity

Septic encephalopathy is associated with rapid deterioration of cortical functions. Using magnetic resonance imaging (MRI) we detected functional abnormalities in the hippocampal formation of patients with septic delirium. Hippocampal dysfunction was further investigated in an animal model for sepsis using lipopolysaccharide (LPS) injections to induce endotoxemia in rats, followed by electrophysiological recordings in brain slices. Endotoxemia induced a deficit in long term potentiation which was completely reversed by apamin, a blocker of small conductance calcium-activated potassium (SK) channels, and partly restored by treatment with physostigmine (eserine), an acetylcholinesterase inhibitor, or TBPB, a selective M1 muscarinic acetylcholine receptor agonist. These results suggest a novel role for SK channels in the etiology of endotoxemia and explain why boosting cholinergic function restores deficits in synaptic plasticity. Drugs which enhance cholinergic or M1 activity in the brain may prove beneficial in treatment of septic delirium in the intensive care unit.

The protocol of the Oslo Study of Clonidine in Elderly Patients with Delirium; LUCID: a randomised placebo-controlled trial

Background

Delirium affects 15% of hospitalised patients and is linked with poor outcomes, yet few pharmacological treatment options exist. One hypothesis is that delirium may in part result from exaggerated and/or prolonged stress responses. Dexmedetomidine, a parenterally-administered alpha2-adrenergic receptor agonist which attenuates sympathetic nervous system activity, shows promise as treatment in ICU delirium. Clonidine exhibits similar pharmacodynamic properties and can be administered orally. We therefore wish to explore possible effects of clonidine upon the duration and severity of delirium in general medical inpatients.

Methods/Design

The Oslo Study of Clonidine in Elderly Patients with Delirium (LUCID) is a randomised, placebo-controlled, double-blinded, parallel group study with 4-month prospective follow-up. We will recruit 100 older medical inpatients with delirium or subsyndromal delirium in the acute geriatric ward. Participants will be randomised to oral clonidine or placebo until delirium free for 2 days (Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria), or after a maximum of 7 days treatment. Assessment of haemodynamics (blood pressure, heart rate and electrocardiogram) and delirium will be performed daily until discharge or a maximum of 7 days after end of treatment. The primary endpoint is the trajectory of delirium over time (measured by Memorial Delirium Assessment Scale). Secondary endpoints include the duration of delirium, use of rescue medication for delirium, pharmacokinetics and pharmacodynamics of clonidine, cognitive function after 4 months, length of hospital stay and need for institutionalisation.

Discussion

LUCID will explore the efficacy and safety of clonidine for delirium in older medical inpatients.

Trial registration

ClinicalTrials.gov NCT01956604. EudraCT Number: 2013-000815-26

Treating an established episode of delirium in palliative care: expert opinion and review of the current evidence base with recommendations for future development

CONTEXT

Delirium is a highly prevalent complication in patients in palliative care settings, especially in the end-of-life context.

OBJECTIVES

To review the current evidence base for treating episodes of delirium in palliative care settings and propose a framework for future development.

METHODS

We combined multidisciplinary input from delirium researchers and other purposely selected stakeholders at an international delirium study planning meeting. This was supplemented by a literature search of multiple databases and relevant reference lists to identify studies regarding therapeutic interventions for delirium.

RESULTS

The context of delirium management in palliative care is highly variable. The standard management of a delirium episode includes the investigation of precipitating and aggravating factors followed by symptomatic treatment with drug therapy. However, the intensity of this management depends on illness trajectory and goals of care in addition to the local availability of both investigative modalities and therapeutic interventions. Pharmacologically, haloperidol remains the practice standard by consensus for symptomatic control. Dosing schedules are derived from expert opinion and various clinical practice guidelines as evidence-based data from palliative care settings are limited. The commonly used pharmacologic interventions for delirium in this population warrant evaluation in clinical trials to examine dosing and titration regimens, different routes of administration, and safety and efficacy compared with placebo.

CONCLUSION

Delirium treatment is multidimensional and includes the identification of precipitating and aggravating factors. For symptomatic management, haloperidol remains the practice standard. Further high-quality collaborative research investigating the appropriate treatment of this complex syndrome is needed.

Underrepresentation of patients with pre-existing cognitive impairment in pharmaceutical trials on prophylactic or therapeutic treatments for delirium: a systematic review

OBJECTIVE

Representation of hospitalized patients with pre-existing cognitive impairment in pharmaceutical delirium trials is important because these patients are at high risk for developing delirium. The aim of this systematic review is to investigate whether patients with cognitive impairment were included in studies on pharmacological prophylaxis or treatment of delirium and to explore the motivations for their exclusion (if they were excluded).

STUDY DESIGN

This study was a systematic review. A MEDLINE search was performed for publications dated from 1 January 1985 to 15 November 2012. Randomized and non-randomized controlled trials that investigated medication to prevent or treat delirium were included. The number of patients with cognitive impairment was counted, and if they were excluded, motivations were noted.

RESULTS

The search yielded 4293 hits, ultimately resulting in 31 studies that met the inclusion criteria. Of these, five studies explicitly mentioned the percentage of patients with cognitive impairment that were included. These patients comprised a total of 8% (n = 279 patients) of the 3476 patients included in all 31 studies. Ten studies might have included cognitively impaired patients but did not mention the exact percentage, and sixteen studies excluded all patients with cognitive impairment. The motivations for exclusion varied, but most were related to the influence of dementia on delirium.

CONCLUSION

The exclusion of patients with pre-existing cognitive impairment hampers the generalizability of the results of these trials and leaves clinicians with limited evidence about the pharmacological treatment of this group of vulnerable patients who have an increased risk of side effects.

Interventions for preventing delirium in older people in institutional long-term care

BACKGROUND

Delirium is a common and distressing complication of a range of stressor events including infection, new medications and environment change that is often experienced by older people with frailty and dementia. Older people living in institutional long-term care (LTC)are at high risk of delirium, which increases the risk of admission to hospital, development of or worsening of dementia, and mortality.Delirium is also associated with substantial healthcare costs. Although it is possible to prevent delirium in the hospital setting by providing multicomponent delirium prevention interventions it is currently unclear whether interventions to prevent delirium in LTCare effective.

OBJECTIVES

To assess the effectiveness of interventions for preventing delirium in older people in long term care.

SEARCH METHODS

We searched ALOIS (www.medicine.ox.ac.uk/alois) - the Cochrane Dementia and Cognitive Improvement Group's Specialised Register- on 23 April 2013. The search was as sensitive as possible to identify all studies on ALOIS relating to delirium. We ran additional separate searches in major healthcare databases, trial registers, the Cochrane Central Register of Controlled Trials (CENTRAL) and grey literature sources, to ensure that the search was as comprehensive as possible.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and cluster-randomised controlled trials (cluster-RCTs) of single- and multi componentn on-pharmacological and pharmacological interventions for preventing delirium in older people (aged 65 years and over) in permanent LTC residence.

DATA COLLECTION AND ANALYSIS

Two independent review authors examined the titles and abstracts of citations identified by the search for eligibility and extracted data, with any disagreements settled by consensus. Primary outcomes were prevalence, incidence and severity of delirium. Secondary outcomes included new diagnosis of dementia, activities of daily living, quality of life and adverse outcomes. We used risk ratios (RRs)as measures of treatment effect for dichotomous outcomes and hazard ratios (HR) for time to event data.Main results We included two trials that recruited 3636 participants.Both were complex single-component non-pharmacological delirium prevention interventions. Risk of bias for many items was unclear due to inadequate reporting. Notably, there was no evidence of blinding of trial participants or assessors in either trial. One small cluster-RCT (n = 98) of a hydration-based intervention reported no reduction in delirium incidence in the intervention group compared to control (RR 0.85, 95% confidence interval (CI) 0.18 to 4.00, analysis not adjusted for clustering, very low quality evidence). Results were imprecise and there were serious limitations evident in trial design.One large cluster-RCT (n = 3538) of a computerised system to identify medications that may contribute to delirium risk and trigger a pharmacist-led medication review reported a large reduction in delirium incidence (12-month HR 0.42, CI 0.34 to 0.51, moderat equality evidence) but no clear evidence of reduction in hospital admissions (HR 0.89, CI 0.72 to 1.10, moderate quality evidence), in mortality (HR 0.88, CI 0.66 to 1.17, moderate quality evidence) or in falls risk (HR 1.03, CI 0.92 to 1.15, moderate quality evidence).Authors' conclusions Our review identified very limited evidence on interventions for preventing deliriumin older people in LTC. Introduction of a software based intervention to identify medications that could contribute to delirium risk so that a pharmacist-led medication review and monitoring plan can be initiated may reduce incidence of delirium for older people in institutional LTC. This is based on one large RCT in the United States and may not be practical in other countries which do not have comparable information technology services available in care homes. Our review identified only one ongoing pilot trial of a multicomponent delirium prevention intervention and no trials of pharmacological agents. Future trials of computerised medication management systems and multicomponent non-pharmacological and pharmacological delirium prevention interventions for older people in LTC are needed to help inform the provision of evidence based care for this vulnerable group.

[Delirium in elderly patients]

BACKGROUND

Delirium, «acute confusional state», is a frequent and serious complication of acute illness, particularly in the elderly. The strain on the patient, the next of kin and the health service is considerable. The purpose of the article is to provide healthcare personnel who deal with delirium with updated information about the condition.

METHOD

The article is based on a literature search in PubMed combined with articles from the author's own archives and own clinical experience.

RESULTS

Delirium is a serious acute medical condition that is often overlooked in the elderly. The prevalence is estimated to be between 11% and 42% for elderly patients on medical wards and close to 50% in patients with hip fractures. The prevalence is probably also high in nursing homes, but this is less well surveyed. Advanced age and dementia are the most important risk factors. Traumas, infections, stroke and metabolic disturbances are the most common triggering factors. The pathophysiology is poorly surveyed and the possibilities for drug treatment are few and are little studied. Delirium is associated with increased risk of dementia, loss of function and mortality. Short-term use of low-dosage antipsychotics is the first-line choice, but is contraindicated for patients with Parkinsonian symptoms.

INTERPRETATION

Detection and treatment of triggering causes must have high priority in case of delirium. Non-drug interventions are most important to prevent and treat the condition.

Delirium in critically ill patients: epidemiology, pathophysiology, diagnosis and management

Delirium is commonly observed in critically ill patients and is associated with negative outcomes. The pathophysiology of delirium is not completely understood. However, alterations to neurotransmitters, especially acetylcholine and dopamine, inflammatory pathways and an aberrant stress response are proposed mechanisms leading to intensive care unit (ICU) delirium. Detection of delirium using a validated delirium assessment tool makes early treatment possible, which may improve prognosis. Patients at high risk of delirium, especially those with cognitive decline and advanced age, should be identified in the first 24 hours of admission to the ICU. Whether these high-risk patients benefit from haloperidol prophylaxis deserves further study. The effectiveness of a multicomponent, non-pharmacological approach is shown in non-ICU patients, which provides proof of concept for use in the ICU. The few studies on this approach in ICU patients suggest that the burden of ICU delirium may be reduced by early mobility, increased daylight exposure and the use of earplugs. In addition, the combined use of sedation, ventilation, delirium and physical therapy protocols can reduce the frequency and severity of adverse outcomes and should become part of routine practice in the ICU, as should avoidance of deliriogenic medication such as anticholinergic drugs and benzodiazepines. Once delirium develops, symptomatic treatment with antipsychotics is recommended, with haloperidol being the drug of first choice. However, there is limited evidence on the safety and effectiveness of antipsychotics in ICU delirium.

Comprehensive approaches to managing delirium in patients with advanced cancer

Delirium is a frequently under-recognized complication in patients with advanced cancer. Uncontrolled delirium eventually leads to significant distress to patients and their families. However, delirium episodes can be reversed in half of these patients by eliminating precipitating factors and using appropriate interventions. The purpose of this narrative review is to discuss the most recent updates in the literature on the management of delirium in patients with advanced cancer. This article addresses the epidemiology, cause, pathophysiology, clinical characteristics, and assessment of delirium as well as various treatment options, including nonpharmacologic intervention and palliative sedation.

Statistical methods in randomised controlled trials for delirium

OBJECTIVE

The analysis of clinical trials in delirium is typically complicated by treatment dropouts and by the fact that even untreated individuals may have a good prognosis. These features of delirium trials warrant special statistical attention; implications for each stage of a trial planning process are described.

METHODS

Choice of outcome, patient sample, and data collection in delirium trials are discussed. Descriptions are given, together with examples, of time-to-event, imputation-based, linear and nonlinear models for the analysis of randomised controlled trials for delirium.

RESULTS

Imputation allows evaluation of the plausibility of individual recovery trajectories, but some simple imputations are found to be unsuitable for delirium research. Time-to-event and nonlinear models encourage a global perspective on analysis, which is often preferable to cross-sectional end-of-trial assessments. It is suggested that nonlinear random effects models for longitudinal trajectories are particularly suitable in a delirium context.

CONCLUSION

It is hoped that the methods described, and nonlinear models in particular, will play a part in convincing analyses of future delirium research.

Evidence-based treatment of delirium in patients with cancer

Delirium is the most common neuropsychiatric complication seen in patients with cancer, and it is associated with significant morbidity and mortality. Increased health care costs, prolonged hospital stays, and long-term cognitive decline are other well-recognized adverse outcomes of delirium. Improved recognition of delirium and early treatment are important in diminishing such morbidity. There has been an increasing number of studies published in the literature over the last 10 years regarding delirium treatment as well as prevention. Antipsychotics, cholinesterase inhibitors, and alpha-2 agonists are the three groups of medications that have been studied in randomized controlled trials in different patient populations. In patients with cancer, the evidence is most clearly supportive of short-term, low-dose use of antipsychotics for controlling the symptoms of delirium, with close monitoring for possible adverse effects, especially in older patients with multiple medical comorbidities. Nonpharmacologic interventions also appear to have a beneficial role in the treatment of patients with cancer who have or are at risk for delirium. This article presents evidence-based recommendations based on the results of pharmacologic and nonpharmacologic studies of the treatment and prevention of delirium.

Butyrylcholinesterase genotype and gender influence Alzheimer's disease phenotype

Retrospective data are presented to support a spectrum of early Alzheimer's disease (AD) along a continuum defined by gender and genotype. The putative neurodegenerative mechanisms driving distinct phenotypes at each end of the spectrum are glial hypoactivity associated with early failure of synaptic cholinergic neurotransmission and glial overactivation associated with loss of neural network connectivity due to accelerated age-related breakdown of myelin. In early AD, male butyrylcholinesterase K-variant carriers with one or two apolipoprotein ɛ4 alleles have prominent medial temporal atrophy, synaptic failure, cognitive decline, and accumulation of aggregated beta-amyloid peptide. Increasing synaptic acetylcholine in damaged but still functional cholinergic synapses improves cognitive symptoms, whereas increasing the ability of glia to support synapses and to clear beta-amyloid peptide might be disease-modifying. Conversely, chronic glial overactivation can also drive degenerative processes and in butyrylcholinesterase K-variant negative females generalized glial overactivation may be the main driver from mild cognitive impairment to AD. Females are more likely than males to have accelerated age-related myelin breakdown, more widespread white matter loss, loss of neural network connectivity, whole brain atrophy, and functional decline. Increasing extracellular acetylcholine levels blocks glial activation, reduces myelin loss and damage to neural network connectivity, and is disease-modifying. Between extremes characterized by gender, genotype, and age, pathophysiology may be mixed and this spectrum may explain much of the heterogeneity of amnestic mild cognitive impairment. Preservation of the functional integrity of the neural network may be an important component of strengthening cognitive reserve and significantly delaying the onset and progression of dementia, particularly in females. Prospective confirmation of these hypotheses is required. Implications for future research and therapeutic opportunities are discussed.

Delirium in older adults

Delirium is a common neuropsychiatric syndrome in the elderly that can occur in several different settings caused by several different processes. It is common and causes increased morbidity and mortality to those affected. This clinical review discusses the prediction, prevention, diagnosis, and treatment of delirium in the elderly population. Several strategies to predict delirium are noted with the discussion of pharmacological and nonpharmacological trials of prevention and treatment. Diagnosis of delirium, specifically with the use of objective instruments, is discussed, as is the evidence for pharmacological and nonpharmacological treatment strategies. Discussion of the neurobiology and genetic markers for delirium may elucidate further areas for future research.

A clinical update on delirium: from early recognition to effective management

Delirium is a neuropsychiatric syndrome characterized by altered consciousness and attention with cognitive, emotional and behavioural symptoms. It is particularly frequent in elderly people with medical or surgical conditions and is associated with adverse outcomes. Predisposing factors render the subject more vulnerable to a congregation of precipitating factors which potentially affect brain function and induce an imbalance in all the major neurotransmitter systems. Early diagnosis of delirium is crucial to improve the prognosis of patients requiring the identification of subtle and fluctuating signs. Increased awareness of clinical staff, particularly nurses, and routine screening of cognitive function with standardized instruments, can be decisive to increase detection rates of delirium. General measures to prevent delirium include the implementation of protocols to systematically identify and minimize all risk factors present in a particular clinical setting. As soon as delirium is recognized, prompt removal of precipitating factors is warranted together with environmental changes and early mobilization of patients. Low doses of haloperidol or olanzapine can be used for brief periods, for the behavioural control of delirium. All of these measures are a part of the multicomponent strategy for prevention and treatment of delirium, in which the nursing care plays a vital role.

Effect of rivastigmine as an adjunct to usual care with haloperidol on duration of delirium and mortality in critically ill patients: a multicentre, double-blind, placebo-controlled randomised trial

BACKGROUND

Delirium is frequently diagnosed in critically ill patients and is associated with adverse outcome. Impaired cholinergic neurotransmission seems to have an important role in the development of delirium. We aimed to establish the effect of the cholinesterase inhibitor rivastigmine on the duration of delirium in critically ill patients.

METHODS

Patients (aged ≥18 years) who were diagnosed with delirium were enrolled from six intensive care units in the Netherlands, and treated between November, 2008, and January, 2010. Patients were randomised (1:1 ratio) to receive an increasing dose of rivastigmine or placebo, starting at 0·75 mL (1·5 mg rivastigmine) twice daily and increasing in increments to 3 mL (6 mg rivastigmine) twice daily from day 10 onwards, as an adjunct to usual care based on haloperidol. The trial pharmacist generated the randomisation sequence by computer, and consecutively numbered bottles of the study drug according to this sequence to conceal allocation. The primary outcome was the duration of delirium during hospital admission. Analysis was by intention to treat. Duration of delirium was censored for patients who died or were discharged from hospital while delirious. Patients, medical staff, and investigators were masked to treatment allocation. Members of the data safety and monitoring board (DSMB) were unmasked and did interim analyses every 3 months. This trial is registered with ClinicalTrials.gov, number NCT00704301.

FINDINGS

Although a sample size of 440 patients was planned, after inclusion of 104 patients with delirium who were eligible for the intention-to-treat analysis (n=54 on rivastigmine, n=50 on placebo), the DSMB recommended that the trial be halted because mortality in the rivastigmine group (n=12, 22%) was higher than in the placebo group (n=4, 8%; p=0·07). Median duration of delirium was longer in the rivastigmine group (5·0 days, IQR 2·7-14·2) than in the placebo group (3·0 days, IQR 1·0-9·3; p=0·06).

INTERPRETATION

Rivastigmine did not decrease duration of delirium and might have increased mortality so we do not recommend use of rivastigmine to treat delirium in critically ill patients.

FUNDING

ZonMw, the Netherlands Brain Foundation, and Novartis.