Exogenous Melatonin for Delirium Prevention: a Meta-analysis of Randomized Controlled Trials

The impact of melatonin on postoperative delirium in geriatric patients after colorectal surgery: a randomized placebo-controlled trial

BACKGROUND

The current study was designed to evaluate the role of prophylactic melatonin administration in reducing delirium occurrence in elderly patients undergoing colorectal cancer surgeries.

METHODS

One hundred patients of both genders undergoing elective colorectal cancer surgeries under general anesthesia were randomly allocated into two equal groups. A treatment group of patients (Melatonin group) received five mg of melatonin the night before surgery, twelve hours before the scheduled surgery time, and an additional five mg of melatonin two hours before surgery. The control group of patients received placebo tablets at the same time points. Delirium score, sedation score, pain score, hemodynamics, oxygen saturation, and blood requirements were recorded.

RESULTS

Twenty-eight patients (56%) in the control group versus 18 (36%) in the melatonin group developed delirium (P=0.045), OR=2.26, 95% CI: 1.013-5.05. Five patients (18%) in the control group versus six (33%) ‎in the melatonin group developed delirium on discharge from the ‎recovery room (P=0.749), OR=1.22, 95% CI: 0.34-4.31, while 23 patients (82%) in the control group versus ‎‎12 (66%) in the melatonin group developed delirium six hours postoperative (P=0.021), OR=1.705, 95% CI: 1.02-2.81 ‎with higher nursing delirium screening score in the control group 2 (1, 4) versus 1 (0, 2) in the melatonin group (P=0.002), 95% CI: 1.77-2.71.

CONCLUSIONS

The prophylactic administration of melatonin may decrease the incidence of postoperative delirium in elderly patients undergoing colorectal surgeries under general anesthesia.

Towards experimental models of delirium utilizing zebrafish

Delirium is an acute neuropsychiatric condition characterized by impaired behavior and cognition. Although the syndrome has been known for millennia, its CNS mechanisms and risk factors remain poorly understood. Experimental animal models, especially rodent-based, are commonly used to probe various pathogenetic aspects of delirium. Complementing rodents, the zebrafish (Danio rerio) emerges as a promising novel model organism to study delirium. Zebrafish demonstrate high genetic and physiological homology to mammals, easy maintenance, robust behaviors in various sensitive behavioral tests, and the potential to screen for pharmacological agents relevant to delirium. Here, we critically discuss recent developments in the field, and emphasize the developing utility of zebrafish models for translational studies of delirium and deliriant drugs. Overall, the zebrafish represents a valuable and promising aquatic model species whose use may help understand delirium etiology, as well as develop novel therapies for this severely debilitating disorder.

Melatonin for Insomnia in Medical Inpatients: A Narrative Review

In this narrative review, we describe what is known about non-pharmacological and pharmacological treatments for insomnia in medical inpatients, with a focus on melatonin. Hospital-acquired insomnia is common, resulting in shortened total sleep time and more nighttime awakenings. Sleep disturbance has been shown to increase systemic inflammation, pain, and the likelihood of developing delirium in hospital. Treatment for insomnia includes both non-pharmacological and pharmacological interventions, the latter of which requires careful consideration of risks and benefits given the known adverse effects. Though benzodiazepines and non-benzodiazepine benzodiazepine receptor agonists are commonly prescribed (i.e., sedative-hypnotics), they are relatively contraindicated for patients over the age of 65 due to the risk of increased falls, cognitive decline, and potential for withdrawal symptoms after long-term use. Exogenous melatonin has a comparatively low likelihood of adverse effects and drug-drug interactions and is at least as effective as other sedative-hypnotics. Though more research is needed on both its effectiveness and relative safety for inpatients, small doses of melatonin before bedtime may be an appropriate choice for inpatients when insomnia persists despite non-pharmacological interventions.

The effect of non-pharmacologic strategies on prevention or management of intensive care unit delirium: a systematic review

Background: Post-operative delirium is a common complication among adult patients in the intensive care unit. Current literature does not support the use of pharmacologic measures to manage this condition, and several studies explore the potential for the use of non-pharmacologic methods such as early mobility plans or environmental modifications. The aim of this systematic review is to examine and report on recently available literature evaluating the relationship between non-pharmacologic management strategies and the reduction of delirium in the intensive care unit.

Methods: Six major research databases were systematically searched for articles analyzing the efficacy of non-pharmacologic delirium interventions in the past five years. Search results were restricted to adult human patients aged 18 years or older in the intensive care unit setting, excluding terminally ill subjects and withdrawal-related delirium. Following title, abstract, and full text review, 27 articles fulfilled the inclusion criteria and are included in this report.

Results: The 27 reviewed articles consist of 12 interventions with a single-component investigational approach, and 15 with multi-component bundled protocols. Delirium incidence was the most commonly assessed outcome followed by duration. Family visitation was the most effective individual intervention while mobility interventions were the least effective. Two of the three family studies significantly reduced delirium incidence, while one in five mobility studies did the same. Multi-component bundle approaches were the most effective of all; of the reviewed studies, eight of 11 bundles significantly improved delirium incidence and seven of eight bundles decreased the duration of delirium.

Conclusions: Multi-component, bundled interventions were more effective at managing intensive care unit delirium than those utilizing an approach with a single interventional element. Although better management of this condition suggests a decrease in resource burden and improvement in patient outcomes, comparative research should be performed to identify the importance of specific bundle elements.

Melatonin's Benefits and Risks as a Therapy for Sleep Disturbances in the Elderly: Current Insights

Aging is accompanied by circadian changes, including disruptive alterations in the sleep/wake cycle, as well as the beginning of low-degree inflammation ("inflammaging"), a scenario that leads to several chronic illnesses, including cancer, and metabolic, cardiovascular, and neurological dysfunctions. As a result, any effective approach to healthy aging must consider both the correction of circadian disturbance and the control of low-grade inflammation. One of the most important prerequisites for healthy aging is the preservation of robust circadian rhythmicity (particularly of the sleep/wake cycle). Sleep disturbance disrupts various activities in the central nervous system, including waste molecule elimination. Melatonin is a chemical with extraordinary phylogenetic conservation found in all known aerobic creatures whose alteration plays an important role in sleep changes with aging. Every day, the late afternoon/nocturnal surge in pineal melatonin helps to synchronize both the central circadian pacemaker found in the hypothalamic suprachiasmatic nuclei (SCN) and a plethora of peripheral cellular circadian clocks. Melatonin is an example of an endogenous chronobiotic substance that can influence the timing and amplitude of circadian rhythms. Moreover, melatonin is also an excellent anti-inflammatory agent, buffering free radicals, down-regulating proinflammatory cytokines, and reducing insulin resistance, among other things. We present both scientific and clinical evidence that melatonin is a safe drug for treating sleep disturbances in the elderly.

Melatonin for prevention of postoperative delirium after lower limb fracture surgery in elderly patients (DELIRLESS): study protocol for a multicentre randomised controlled trial

INTRODUCTION

Postoperative delirium (POD) is one of the most frequent complication after surgery in elderly patients, and is associated with increased morbidity and mortality, prolonged length of stay, cognitive and functional decline leading to loss of autonomy, and important additional healthcare costs. Perioperative inflammatory stress is a key element in POD genesis. Melatonin exhibits antioxidative and immune-modulatory proprieties that are promising concerning delirium prevention, but in perioperative context literature are scarce and conflicting. We hypothesise that perioperative melatonin can reduce the incidence of POD.

METHODS AND ANALYSIS

The DELIRLESS trial is a prospective, national multicentric, phase III, superiority, comparative randomised (1:1) double-blind clinical trial. Among patients aged 70 or older, hospitalised and scheduled for surgery of a severe fracture of a lower limb, 718 will be randomly allocated to receive either melatonin 4 mg per os or placebo, every night from anaesthesiologist preoperative consultation and up to 5 days after surgery. The primary outcome is POD incidence measured by either the French validated translation of the Confusion Assessment Method (CAM) score for patients hospitalised in surgery, or CAM-ICU score for patients hospitalised in ICU (Intensive Care Unit). Daily delirium assessment will take place during 10 days after surgery, or until the end of hospital stay if it is shorter. POD cumulative incidence function will be compared at day 10 between the two randomised arms in a competing risks framework, using the Fine and Grey model with death as a competing risk of delirium.

ETHICS AND DISSEMINATION

The DELIRLESS trial has been approved by an independent ethics committee the Comité de Protection des Personnes (CPP) Sud-Est (ref CPP2020-18-99 2019-003210-14) for all study centres. Participant recruitment begins in December 2020. Results will be published in international peer-reviewed medical journals.

TRIAL REGISTRATION NUMBER

NCT04335968, first posted 7 April 2020.

PROTOCOL VERSION IDENTIFIER

N°3-0, 3 May 2021.

Melatonin and melatonin-receptor agonists to prevent delirium in hospitalized older adults: An umbrella review

BACKGROUND

Alterations in circadian rhythm play an important role in the development of delirium. In this umbrella review, we examined the efficacy of melatonin and ramelteon for delirium prevention in hospitalized older adults.

METHODS

Umbrella review methodology from the Joanna Briggs Institute guided the review process. Only meta-analyses were included. Risk of bias was evaluated using the AMSTAR-2 checklist.

RESULTS

Three meta-analyses were included in this review. The quality of studies was low-to-moderate. Two meta-analyses reported a significant reduction in delirium using melatonin or ramelteon (pooled OR and 95% confidence intervals ranged from 0.41 [0.19-0.86] to 0.63 [0.46-0.87]). Melatonergics significantly reduced delirium on medical units (OR = 0.25, 95% CI 0.07-0.88) but not surgical units (OR = 0.62, 0.16-2.43). Heterogenity was high, with I² ranging from 72.14% to 84%.

CONCLUSIONS

Melatonergics appear to prevent delirium among hospitalized older adults, particularly those on medical units. Based on these results, providers may consider using melatonergics as complements to high-quality multicomponent delirium prevention.

Effects of perioperative interventions for preventing postoperative delirium: A protocol for systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Postoperative delirium (POD) not only increases the medical burden but also adversely affects patient prognosis. Although some cases of delirium can be avoided by early intervention, there is no clear evidence indicating whether any of these measures can effectively prevent POD in specific patient groups.

OBJECTIVE

The aim of this meta-analysis was to compare the efficacy and safety of the existing preventive measures for managing POD.

METHODS

The PubMed, OVID (Embase and MEDLINE), Web of Science, and the Cochrane Library databases were searched for articles published before January 2020. The relevant randomized controlled trials (RCTs) were selected based on the inclusion and exclusion criteria. Data extraction and methodological quality assessment were performed according to a predesigned data extraction form and scoring system, respectively. The interventions were compared on the basis of the primary outcome like incidence of POD, and secondary outcomes like duration of delirium and the length of intensive care unit and hospital stay.

RESULTS

Sixty-three RCTs were included in the study, covering interventions like surgery, anesthesia, analgesics, intraoperative blood glucose control, cholinesterase inhibitors, anticonvulsant drugs, antipsychotic drugs, sleep rhythmic regulation, and multi-modal nursing. The occurrence of POD was low in 4 trials that monitored the depth of anesthesia with bispectral index during the operation (P < .0001). Two studies showed that supplementary analgesia was useful for delirium prevention (P = .002). Seventeen studies showed that perioperative sedation with α2-adrenergic receptor agonists prevented POD (P = .0006). Six studies showed that both typical and atypical antipsychotic drugs can reduce the incidence of POD (P = .002). Multimodal nursing during the perioperative period effectively reduced POD in 6 studies (P < .00001). Furthermore, these preventive measures can reduce the duration of delirium, as well as the total and postoperative length of hospitalized stay for non-cardiac surgery patients. For patients undergoing cardiac surgery, effective prevention can only reduce the length of intensive care unit stay.

CONCLUSION

Measures including intraoperative monitoring of bispectral index, supplemental analgesia, α2-adrenergic receptor agonists, antipsychotic drugs, and multimodal care are helpful to prevent POD effectively. However, larger, high-quality RCTs are needed to verify these findings and develop more interventions and drugs for preventing postoperative delirium.

Delirium in the acute hospital setting: the role of psychiatry

In this overview we discuss the role of psychiatry in managing delirium in acute hospital admissions. We briefly discuss the role psychiatry can offer in four main domains: (a) assessment; (b) management; (c) recovery; and (d) paradigm, education and research. In the assessment section we discuss accurately detecting delirium in the context of comorbid mixed neuropsychiatric syndromes, including depression and dementia, and the clinical importance of delirium subtyping. The management section briefly outlines pharmacological and non-pharmacological approaches to delirium and their evidence-based rationale. The recovery section focuses on the effect delirium can have on cognitive decline, mental health and long-term health, including functional outcome and need for institutional care after hospital discharge. Finally, we outline the role of psychiatry in delirium research and education. We hope that this article will encourage clinicians to reflect on their current practice and consider holistic and evidence-based care for this vulnerable population in the acute hospital setting.

Melatonin for delirium prevention in hospitalized patients: A systematic review and meta-analysis

BACKGROUND AND AIMS

Melatonin, a pineal gland hormone is reported to have a protective effect against delirium. This systematic review and meta-analysis explores the effect of melatonin and melatonin receptor agonist, ramelteon on delirium prevention in adult hospitalized patients.

METHODS

Randomized Controlled trials of melatonin/ramelteon published up to May 7, 2020 were identified from MEDLINE, PREMEDLINE, Embase, PsycINFO, the Cochrane Central Register of Controlled trials, PubMed, and Google Scholar. The primary outcome was delirium incidence. The secondary outcomes were sleep quality, sedation score, sedatives requirement, delirium duration, length of hospital stay, length of Intensive Care Unit (ICU) stay, mortality and adverse events. A meta-analysis with a random-effects models was performed. Estimates were presented as Risk Ratio (RR) or Mean Differences (MD) with 95% Confidence Interval (CI).

FINDINGS

Fourteen studies with 1712 participants were included. Melatonin/ramelteon significantly reduced delirium incidence (RR 0·61, 95% CI 0·42-0·89, p 0·009) with risk reduction of 49% in surgical patients and 34% in ICU patients. Non-significant reduction was found in medical patients. Melatonin/ramelteon were associated with improvement in sleep quality, increased sedation score and lower sedatives consumption. However, they did not reduce delirium duration, length of hospital stay, length of ICU stay and mortality. Hallucinations, nightmares and gastrointestinal disorders were prevalent in melatonin group.

INTERPRETATION

Melatonin/ramelteon are associated with reduction in delirium incidence in hospitalized patients. However, this effect seems confined to surgical and ICU patients. The optimum dosage and formulation of melatonin, and treatment duration remain uncleared and open to further studies with larger sample sizes.

Melatonin to prevent delirium in patients with advanced cancer: a double blind, parallel, randomized, controlled, feasibility trial

BACKGROUND

Delirium is highly problematic in palliative care (PC). Preliminary data indicate a potential role for melatonin to prevent delirium, but no randomized controlled trials (RCTs) are reported in PC.

METHODS

Patients aged ≥18 years, with advanced cancer, admitted to an inpatient Palliative Care Unit (PCU), having a Palliative Performance Scale rating ≥ 30%, and for whom consent was obtained, were included in the study. Patients with delirium on admission were excluded. The main study objectives were to assess the feasibility issues of conducting a double-blind RCT of exogenous melatonin to prevent delirium in PC: recruitment, retention, procedural acceptability, appropriateness of outcome measures, and preliminary efficacy and safety data. Study participants were randomized in a double-blind, parallel designed study to receive daily melatonin 3 mg or placebo orally at 21:00 over 28 days or less if incident delirium, death, discharge or withdrawal occurred earlier. Delirium was diagnosed using the Confusion Assessment Method. Efficacy endpoints in the melatonin and placebo groups were compared using time-to-event analysis: days from study entry to onset of incident delirium.

RESULTS

Over 16 months, 60/616 (9.7%; 95% CI: 7.5-12.4%) screened subjects were enrolled. The respective melatonin (n = 30) vs placebo (n = 30) outcomes were: incident delirium in 11/30 (36.7%; 95%CI: 19.9-56.1%) vs 10/30 (33%; 95% CI: 17.3-52.8%); early discharge (6 vs 5); withdrawal (6 vs 3); death (0 vs 1); and 7 (23%) vs 11 (37%) reached the 28-day end point. The 25th percentile time-to-event were 9 and 18 days (log rank, χ² = 0.62, p = 0.43) in melatonin and placebo groups, respectively. No serious trial medication-related adverse effects occurred and the core study procedures were acceptable. Compared to those who remained delirium-free during their study participation, those who developed delirium (n = 21) had poorer functional (p = 0.036) and cognitive performance (p = 0.013), and in particular, poorer attentional capacity (p = 0.003) at study entry.

CONCLUSIONS

A larger double-blind RCT is feasible, but both subject accrual and withdrawal rates signal a need for multisite collaboration. The apparent trend for shorter time to incident delirium in the melatonin group bodes for careful monitoring in a larger trial.

TRIAL REGISTRATION

Registered on July 21st 2014 with ClinicalTrials.gov : NCT02200172 .

Objectively measured sleep fragmentation is associated with incident delirium in older hospitalized patients: Analysis of data collected from an randomized controlled trial

Delirium may lead to poor outcomes in hospitalized older adults, and sleep deprivation may contribute to its pathogenesis. Thus, we sought to measure sleep duration and fragmentation using wrist-worn actigraphy in older, hospitalized patients with and without delirium, and to determine if actigraphy-based parameters could be used to predict delirium prior to clinical recognition. We conducted a secondary analysis of data from a recent, randomized clinical trial aimed at preventing inpatient delirium. Participants (n = 70) were aged ≥ 65 years admitted to an internal medicine service. Delirium was defined by the Confusion Assessment Method, or altered mental status identified by a clinician. Sleep measurements were actigraphy-based, and included total sleep time, median sleep bout duration and other measures of sleep fragmentation. We found that total sleep duration was similar between patients with (n = 17) and without (n = 53) delirium (mean 384.9 ± SD 162.7 versus mean 456.6 ± SD 135.8 min; p = .081). Mean sleep bout times were shorter in delirious versus never-delirious patients (median 6.1 [interquartile range 4.3-8.9] versus 7.9 [interquartile range 5.7-11.3] min, p = .048). Patients with delirium had more short sleep bouts (< 10 min) and fewer longer sleep bouts (> 30 min) compared with those without delirium. Increased sleep fragmentation was present prior to the clinical recognition of delirium. Overall, delirium was associated with increased sleep fragmentation detected by actigraphy, and sleep fragmentation might be useful as a biomarker for delirium prediction in the future.

The effect of non-pharmacologic strategies on prevention or management of intensive care unit delirium: a systematic review

Background: Post-operative delirium is a common complication among adult patients in the intensive care unit. Current literature does not support the use of pharmacologic measures to manage this condition, and several studies explore the potential for the use of non-pharmacologic methods such as early mobility plans or environmental modifications. The aim of this systematic review is to examine and report on recently available literature evaluating the relationship between non-pharmacologic management strategies and the reduction of delirium in the intensive care unit. Methods: Six major research databases were systematically searched for articles analyzing the efficacy of non-pharmacologic delirium interventions in the past five years. Search results were restricted to adult human patients aged 18 years or older in the intensive care unit setting, excluding terminally ill subjects and withdrawal-related delirium. Following title, abstract, and full text review, 27 articles fulfilled the inclusion criteria and are included in this report. Results: The 27 reviewed articles consist of 12 interventions with a single-component investigational approach, and 15 with multi-component bundled protocols. Delirium incidence was the most commonly assessed outcome followed by duration. Family visitation was the most effective individual intervention while mobility interventions were the least effective. Two of the three family studies significantly reduced delirium incidence, while one in five mobility studies did the same. Multi-component bundle approaches were the most effective of all; of the reviewed studies, eight of 11 bundles significantly improved delirium incidence and seven of eight bundles decreased the duration of delirium. Conclusions: Multi-component, bundled interventions were more effective at managing intensive care unit delirium than those utilizing an approach with a single interventional element. Although better management of this condition suggests a decrease in resource burden and improvement in patient outcomes, comparative research should be performed to identify the importance of specific bundle elements.

The effect of non-pharmacologic strategies on prevention or management of intensive care unit delirium: a systematic review

Background: Post-operative delirium is a common complication among adult patients in the intensive care unit. Current literature does not support the use of pharmacologic measures to manage this condition, and several studies explore the potential for the use of non-pharmacologic methods such as early mobility plans or environmental modifications. The aim of this systematic review is to examine and report on recently available literature evaluating the relationship between non-pharmacologic management strategies and the reduction of delirium in the intensive care unit. Methods: Six major research databases were systematically searched for articles analyzing the efficacy of non-pharmacologic delirium interventions in the past five years. Search results were restricted to adult human patients aged 18 years or older in the intensive care unit setting, excluding terminally ill subjects and withdrawal-related delirium. Following title, abstract, and full text review, 27 articles fulfilled the inclusion criteria and are included in this report. Results: The 27 reviewed articles consist of 12 interventions with a single-component investigational approach, and 15 with multi-component bundled protocols. Delirium incidence was the most commonly assessed outcome followed by duration. Family visitation was the most effective individual intervention while mobility interventions were the least effective. Two of the three family studies significantly reduced delirium incidence, while one in five mobility studies did the same. Multi-component bundle approaches were the most effective of all; of the reviewed studies, eight of 11 bundles significantly improved delirium incidence and seven of eight bundles decreased the duration of delirium. Conclusions: Multi-component, bundled interventions were more effective at managing intensive care unit delirium than those utilizing an approach with a single interventional element. Although better management of this condition suggests a decrease in resource burden and improvement in patient outcomes, comparative research should be performed to identify the importance of specific bundle elements.

Circadian disruption, melatonin rhythm perturbations and their contributions to chaotic physiology

The aim of this report is to summarize the data documenting the vital nature of well-regulated cellular and organismal circadian rhythms, which are also reflected in a stable melatonin cycle, in supporting optimal health. Cellular fluctuations in physiology exist in most cells of multicellular organisms with their stability relying on the prevailing light:dark cycle, since it regulates, via specialized intrinsically-photoreceptive retinal ganglion cells (ipRGC) and the retinohypothalamic tract, the master circadian oscillator, i.e., the suprachiasmatic nuclei (SCN). The output message of the SCN, as determined by the light:dark cycle, is transferred to peripheral oscillators, so-called slave cellular oscillators, directly via the autonomic nervous system with its limited distribution. and indirectly via the pineal-derived circulating melatonin rhythm, which contacts every cell. Via its regulatory effects on the neuroendocrine system, particularly the hypothalamo-pituitary-adrenal axis, the SCN also has a major influence on the adrenal glucocorticoid rhythm which impacts neurological diseases and psychological behaviors. Moreover, the SCN regulates the circadian production and secretion of melatonin. When the central circadian oscillator is disturbed, such as by light at night, it passes misinformation to all organs in the body. When this occurs the physiology of cells becomes altered and normal cellular functions are compromised. This physiological upheaval is a precursor to pathologies. The deterioration of the SCN/pineal network is often a normal consequence of aging and its related diseases, but in today's societies where manufactured light is becoming progressively more common worldwide, the associated pathologies may also be occurring at an earlier age.

Melatonin for delirium prevention in acute medically ill, and perioperative geriatric patients

Delirium is a challenging neuropsychiatric ailment that has a negative impact on morbidity and mortality and is difficult to treat once it has developed. The purpose of this review was to analyze the efficacy of melatonin in the prevention of delirium in hospitalized geriatric patients in the acute medically ill and perioperative wards. The databases searched included PubMed (1946 to February 12, 2020), CINAHL (1982 to February 12, 2020), EMBASE (1974 to February 12, 2020), and Web of Science (1900 to February 12, 2020) using search terms related to melatonin, delirium, and prevention. Meta-analyses, randomized controlled trials, and observational studies were included. We excluded publications pertaining to the intensive care unit or oncology, case reports/series, and those not in English. Seven full-text publications were included for qualitative analysis. Patient comorbidities, patient medications, melatonin dosing, dosing regimens, and duration of treatment varied between the studies, which yielded heterogeneous results. Overall, this literature review yielded four studies that showed positive results and three that showed negative results for delirium prevention. The current data for the use of melatonin in delirium is conflicting. This area requires further research of more homogeneous studies with larger sample sizes.

Melatonin and its analogues for the prevention of postoperative delirium: A systematic review and meta-analysis

It remains unclear whether melatonin and its analogues prevent postoperative delirium (POD). Therefore, we conducted a systematic review and meta-analysis to evaluate the effect of melatonin and its analogues on POD prevention. PubMed, Cochrane Library, Web of Science, Embase and CINAHL databases were searched. Primary outcome was the incidence of POD. Six randomized controlled trials, 2 cohort studies and 1 case-control study were included in this meta-analysis. Results showed that melatonin and its analogue ramelteon decreased the incidence of POD in the entire adult surgical population (odds ratio [OR] = 0.45, 95% confidence interval [CI] 0.24-0.84, P = .01). When administered at a higher dose (5 mg), melatonin was effective in reducing the POD incidence (OR = 0.32, 95% CI 0.20-0.52, P < .00001). Melatonin administered less than 5 elimination half-lives before the surgery significantly reduced the POD incidence (OR = 0.31, 95% CI 0.19-0.49, P < .00001). Current literature supports the effectiveness of melatonin and its analogue ramelteon in POD prevention. However, the present study was limited by the significant heterogeneity of the included studies. More studies are needed to ascertain the preventive effect of melatonin and its analogues on the incidence of delirium after cardiac and noncardiac surgeries.

Considerations and Current Trends in the Management of the Geriatric Patient on a Consultation-Liaison Service

PURPOSE OF REVIEW

To provide consultation-liaison psychiatrists with an updated resource that can assist in the treatment and management of geriatric patients.

RECENT FINDINGS

The current available literature has not shown any differences in efficacy between haloperidol and second-generation antipsychotics in patients with delirium. When considering relative advantages of forms of antipsychotic administration, there is no support for a superior safety profile of oral compared to intramuscular or intravenous administration. A recent meta-analysis of four randomized controlled trials concluded that when melatonin was administered to older age patients on medical wards, it significantly prevented the incidence of delirium when compared with the control group. While suvorexant administered nightly to elderly patients in acute care settings may lower the incidence of delirium, larger studies are needed to confirm this finding. Despite the black box warning of increased mortality risk in older patients with dementia, antipsychotics may be used with caution by the consultation-liaison (CL) psychiatrist to treat the neuropsychologic symptoms of dementia including hallucinations and psychosis in the hospital setting. While antidepressant studies have focused primarily on citalopram and escitalopram in the treatment of agitation in the setting of dementia, these two medications have not been adequately compared directly to other SSRIs for this condition. It is therefore not clear whether citalopram and escitalopram are more efficacious in treating agitation in the setting of dementia when compared to other SSRIs. While the evidence supporting trazodone's use is limited, it is generally well tolerated and is an option as a PRN for irritability and agitation in patients with Alzheimer's and mixed dementia. While there is some evidence to support the use of acetylcholinesterase inhibitors for treating cognitive impairments and hallucinations in Lewy body dementia, the usefulness of these agents in other forms of dementia is not well studied, and those studies did not show any benefit in the management of acute agitation. It is important to note that memantine can cause or exacerbate agitation and may be the cause of behavioral dysregulation. There is no evidence to support the routine use of benzodiazepines for behavioral improvement in patients with dementia. Escitalopram and citalopram do have a unique pharmacokinetic properties in the sense that they have been found to have 50-56% plasma protein binding, compared to sertraline, fluoxetine, and paroxetine (95% or more). Pooled analyses suggest that antidepressants are more effective than placebo in reducing the symptoms of post-stroke depression. SSRIs are considered first-line antidepressants in stroke patients, who are often elderly with underlying cardiovascular problems. Although treatment with SSRIs is recommended for post-stroke depression, there are no studies providing conclusive data on the superiority of a specific drug. Older age is associated with a better outcome from ECT, with remission rates of approximately 73% to 90% in patients over 65 years. ECT is the treatment of choice for patients with psychotic depression, and elderly patients with psychotic depression have been shown to have a higher remission rate and faster time to response than depressed patients without psychotic symptoms. With the average life expectancy increase, it is projected that 19 million people will reach the age of 85 or higher, an increase from 5.5 million in 2010. With an increasing older population, psychiatric consultation in the management of geriatric patients is becoming more necessary. Psychiatrists must be aware of the unique considerations in elderly patients. In this article, we provide evidence-based guidance to the CL psychiatrist on major issues relating to the older age patient, highlighting recent trends in treatment. First, we provide background on the evaluation of the medically hospitalized geriatric patient. As rates of medical and psychiatric illnesses increase with advancing age, elderly patients are more likely to be taking a higher number of medications as compared to younger patients, and physicians must pay special attention to polypharmacy, including side effects and drug interactions in this group. Next, we focus on the diagnosis, management, and unique needs of the geriatric patient presenting with common clinical syndromes of delirium, dementia, and depression. Delirium and dementia are among the most common causes of cognitive impairment in clinical settings yet are often either unrecognized or misdiagnosed as they may have similar signs and symptoms. In addition, depression is prevalent in older adults, especially in those with comorbid medical illness. Depression can be fatal as the rates of suicide are higher in later life than in any other age group. Consultation can improve the management of elderly patients and prevent unnecessary nursing home placement.

Assessment of Melatonergics in Prevention of Delirium: A Systematic Review and Meta-Analysis

Background: Delirium is a commonly found comorbidity in hospitalized patients and is associated with adverse outcomes. Melatonin is an endogenous hormone that exerts multiple biological effects, mainly in regulating diurnal rhythms and in inflammatory process and immune responses. We aimed to assess the efficacy of exogenous melatonergics in the prevention of delirium.

Methods: We conducted a search to identify relevant randomized controlled studies (RCTs) in PubMed, Cochrane Library, and EMBASE databases that had been published up to December 2019. Hospitalized adult patients administered melatonergics were included. The primary outcome measure was the incidence of delirium. The secondary outcome measure was the length of stay in intensive care unit (ICU-LOS). The pooled effects were analyzed as the risk ratio (RR) for delirium incidence, weighted mean difference (WMD) for ICU-LOS, and 95% confidence intervals (CIs).

Results: Nine RCTs with 1,210 patients were included. The forest plots showed that melatonergics were associated with a decreasing incidence of delirium (RR, 0.51; 95% CI, 0.30–0.85; I² = 70%; p = 0.01). There was no significant difference in ICU-LOS (WMD, −0.08; 95% CI, −0.19–0.03; I² = 0; p = 0.17).

Conclusion: Administration of exogenous melatonergics to hospitalized patients seems to be associated with a decreasing incidence of delirium.

PROSPERO registration number: CRD42019138863.

[Delirium in idiopathic Parkinson's disease]

BACKGROUND

The development of delirium in patients with idiopathic Parkinson's disease (IPD) is a feared complication, which is often associated with sustained worsening of motor symptoms and psychopathological sequelae. Little is known regarding the prevalence and incidence rates, course and prognosis. Clinical studies from which recommendations for evidence-based management of delirium in IPD can be derived are lacking.

OBJECTIVE

To summarize the state of the art regarding epidemiological and clinical features of delirium in IPD. Discussion of prevention strategies and non-pharmacological and pharmacological treatment options.

METHODS

A literature search was carried out in PubMed.

RESULTS

The IPD is an independent risk factor for the development of delirium. Patients with IPD show poorer clinical outcome frequently with cognitive worsening and motor complications following development of delirium.

CONCLUSION

So far no validated rating scales for recognition and course evaluation of delirium in IPD are available. Preventive strategies and non-pharmacological measures should be consistently implemented to improve management. There are insufficient data concerning pharmacotherapy with quetiapine and clozapine, whereas other neuroleptics are contraindicated for delirium in IPD due to antidopaminergic side effects.

Assessment of melatonergics in prevention of delirium in critically ill patients: A protocol for systematic review and meta-analysis

BACKGROUND

Delirium is a commonly occurred complication in the critically ill. Melatonin is an endogenous hormone exerting multiple biological effects, mainly in regulating diurnal rhythms, also in inflammatory process and immune response. We aimed to assess the efficacy of exogenous melatonergics in prevention of delirium.

METHODS

PubMed, Cochrane Library, and Embase will be searched to identify randomized controlled trials published from 1960 to April 2019. Critically ill adult patients administrated with melatonergics will be included. The primary outcome measure will be the incidence of delirium. The secondary outcome measure will be the length of stay in intensive care unit. The pooled effects of dichotomous outcomes will be analyzed as risk ratio, and that of continuous outcomes will be analyzed using weighted mean difference. Subgroup and sensitivity analyses will be conducted. Funnel plots and/or Egger test will be done for the examination of publication bias. The quality of evidence resulting from this study will be evaluated using the GRADE methodology. Trial sequential analysis (TSA) will be done to test whether the evidence in our meta-analysis is reliable and conclusive.

RESULT

The evidence to date of the melatonergics in prevention of delirium will be systematically reviewed and meta-analyzed with the GRADE level reported and TSA examined.

CONCLUSION

The stronger evidence for the efficacy of melatonergics in prevention of delirium in critically ill patients will be provided for intensive care physicians.

PROSPERO REGISTRATION NUMBER

CRD42019138863.

[Delirium in intensive care patients : A multiprofessional challenge]

Delirium is the most common form of cerebral dysfunction in intensive care patients and is a medical emergency that must be avoided or promptly diagnosed and treated. According to current knowledge the development of delirium seems to be caused by an interplay between increased vulnerability (predisposition) and simultaneous exposure to delirogenic factors. Since delirium is often overlooked in the clinical routine, a continuous screening for delirium should be performed. Due to the close connection between delirium, agitation and pain, sedation and analgesia must be evaluated at least every 8 h analogous to delirium screening. According to current knowledge, a multifactorial and multiprofessional approach is favored in the prevention and treatment of delirium. Non-pharmaceutical interventions through early mobilization, reorientation, sleep improvement, adequate pain therapy and avoidance of polypharmacy are of great importance. Depending on the clinical picture, different substances are used in symptom-oriented drug treatment of delirium. In order to achieve these diagnostic and therapeutic goals, an interdisciplinary treatment team consisting of intensive care, intensive care physicians, ward pharmacists, physiotherapists, nutrition specialists and psychiatrists is necessary in order to meet the requirements of the patient and their relatives.

Melatonergic agents in the prevention of delirium: A network meta-analysis of randomized controlled trials

Disruption of the sleep-wake cycle is a risk factor and a prodromal indicator of delirium. Melatonergic agents may thus play a role in the prevention of delirium. Based upon literature search on eight databases, this systemic review and frequentist model network meta-analysis (NMA) aimed to determine the efficacy and tolerability of melatonergic agents in delirium prevention. Six randomized controlled trials (RCTs) were included with a total of 913 adult participants (mean age = 78.8, mean female proportion = 59.4%) investigating the preventive effects of melatonergic agents in patients with high risks of developing delirium. The outcomes of NMA demonstrated significant preventive effects with 5 mg/day of melatonin [Odds Ratio (OR) = 0.21, 95% Confidence Intervals (CIs): 0.07 to 0.64], melatonin (0.5 mg/d) [OR = 0.16 (95% CIs: 0.03 to 0.75)], and ramelteon (8 mg/d) [OR = 0.28 (95% CIs: 0.12 to 0.65)] against placebo groups. According to the surface under the cumulative ranking curve (SUCRA), 0.5 mg/d of melatonin was associated with the best preventive effect. Our findings provided the rationale for recommending low-dose melatonergic agents for delirium prevention in the practice guidelines.

Hallucinations, Delusions and Impulse Control Disorders in Parkinson Disease

Psychotic and compulsive symptoms in Parkinson disease are highly prevalent and associated with poor outcomes and greater caregiver burden. When acute, delirium should be ruled out or treated accordingly. When chronic, comorbid systemic illnesses, dementia, and psychiatric disorders should be considered. Reduction and discontinuation of anticholinergics, amantadine, dopamine agonists, and levodopa as tolerated, as well as adjunctive clozapine or quetiapine are frequently effective to manage Parkinson disease psychosis. Pimavanserin appears effective but is not widely available, and more experience is needed. Dopamine agonist discontinuation is usually successful for impulse control disorders, but requires frequent monitoring, documentation, and caregiver involvement.

Melatonin, temazepam and placebo in hospitalised older patients with sleeping problems (MATCH): a study protocol of randomised controlled trial

INTRODUCTION

Hospitalised older patients frequently suffer from inadequate sleep, which can lead to patient distress and delayed recovery from acute illness or surgical procedure. Currently, no evidence-based treatments exist for sleeping problems in hospitalised older patients. Benzodiazepines, such as temazepam, are regularly prescribed by physicians, although they have serious side effects; for older patients in particular. Melatonin is proposed as a safe alternative for sleeping problems in hospitalised older patients, but the efficacy of melatonin is unclear in this population. Therefore, the aim of this study is to investigate the effects of melatonin and temazepam compared with placebo on sleep quality among hospitalised older patients with sleeping problems.

METHODS AND ANALYSIS

This study is a multicentre, randomised, placebo-controlled trial. A total of 663 patients will be randomised in a 1:1:1 fashion to receive either melatonin (n=221), temazepam (n=221) or placebo (n=221). The study population consists of hospitalised patients aged 60 years and older, with new or aggravated sleeping problems for which an intervention is needed. The primary outcome is sleep quality measured with the Leeds Sleep Evaluation Questionnaire (LSEQ). Secondary outcomes include sleep parameters measured with actigraphy and medication-related adverse effects.

ETHICS AND DISSEMINATION

This study was approved by the Medical Ethics Committee of the Academic Medical Centre Amsterdam, (No 2015_302). Study findings will be disseminated through presentations at professional and scientific conferences and publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NTR6908; Pre-results.

Differential MicroRNA Expression of miR-21 and miR-155 within Oral Cancer Extracellular Vesicles in Response to Melatonin

Objective: Extracellular vesicles derived from oral cancer cells, which include Exosomes and Oncosomes, are membranous vesicles secreted into the surrounding extracellular environment. These extracellular vesicles can regulate and modulate oral squamous cell carcinoma (OSCC) progression through the horizontal transfer of bioactive molecules including proteins, lipids and microRNA (miRNA). The primary objective of this study was to examine the potential to isolate and evaluate extracellular vesicles (including exosomes) from various oral cancer cell lines and to explore potential differences in miRNA content. Methods: The OSCC cell lines SCC9, SCC25 and CAL27 were cultured in DMEM containing 10% exosome-free fetal bovine serum. Cell-culture conditioned media was collected for exosome and extracellular vesicle isolation after 72 h. Isolation was completed using the Total Exosome Isolation reagent (Invitrogen) and extracellular vesicle RNA was purified using the Total Exosome RNA isolation kit (Invitrogen). Extracellular vesicle miRNA content was evaluated using primers specific for miR-16, -21, -133a and -155. Results: Extracellular vesicles were successfully isolated from all three OSCC cell lines and total extracellular vesicle RNA was isolated. Molecular screening using primers specific for several miRNA revealed differential baseline expression among the different cell lines. The addition of melatonin significantly reduced the expression of miR-155 in all of the OSCC extracellular vesicles. However, miR-21 was significantly increased in each of the three OSCC isolates. No significant changes in miR-133a expression were observed under melatonin administration. Conclusions: Although many studies have documented changes in gene expression among various cancers under melatonin administration, few studies have evaluated these effects on microRNAs. These results may be among the first to evaluate the effects of melatonin on microRNA expression in oral cancers, which suggests the differential modulation of specific microRNAs, such as miR-21, miR-133a and miR-155, may be of significant importance when evaluating the mechanisms and pathways involved in melatonin-associated anti-tumor effects.

Pharmacological Prevention of Postoperative Delirium: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

The high prevalence of delirium among postoperative patients has increased morbidity and mortality. The kind of drug that can effectively reduce the incidence of delirium has become the focus of discussion in recent years. However, a consensus in this respect has yet to be reached.

Methods

Randomized controlled trials (RCTs) were retrieved from the PubMed, Cochrane Library, ClinicalTrials.gov, and Embase databases from their inception through October 12, 2018. We included RCTs of pharmacological prevention for postoperative delirium in adults (at least 18 years), and the Cochrane risk of bias tool was used to evaluate the methodological quality of trials. The primary outcomes were the risk ratios (RRs) of incidence of postoperative delirium, and the secondary outcomes were the RRs of mortality and adverse events in the intervention and control groups.

Results

Thirty-eight trials, which comprised 20302 patients and 18 different drugs, were included in the analysis. Of the 38 studies, 17 were rated as low risk with respect to methodological quality. Dexmedetomidine administration (RR 0.58, 95%CI 0.44-0.76, P<0.01) was associated with a significantly lower incidence of postoperative delirium than the control conditions. However, the findings from the studies with a low risk of bias did not show a significant difference in this beneficial effect (RR 0.64, 95%CI 0.39-1.04, P=0.07). The antipsychotic drugs olanzapine (RR 0.44, 95%CI 0.30- 0.65, P<0.01) and risperidone (RR 0.42, 95%CI 0.19-0.92, P=0.03) had promising effects, but there was a lack of sufficient evidence to obtain a definitive conclusion. The beneficial effect of other drugs, including haloperidol, methylprednisolone, dexamethasone, gabapentin, ketamine, cyproheptadine, donepezil, hypertonic saline, melatonin, nimodipine, ondansetron, pregabalin, rivastigmine, TJ-54, and tryptophan, was not proven on the basis of present evidence.

Conclusion

Among the pharmacological prophylactic measures for postoperative delirium, dexmedetomidine, olanzapine, and risperidone showed higher efficacy than other drugs. However, more high-quality evidence is needed to confirm these results.

Acute Confusional States in Hospital

BACKGROUND

Acute confusional state (delirium) is an acute disturbance of brain function. The incidence of such states varies according to the group of patients con- cerned: it ranges from 30% to 80% among patients in intensive care and from 5.1% to 52.2% among surgical patients, depending on the type of procedure. The earlier German term "Durchgangssyndrom" (usually rendered as "transitory psychotic syn- drome") tended to imply a self-limited and thus relatively harmless condition. In fact, however, delirium is associated with longer hospital stays, poorer treatment out- comes, and higher mortality. Approximately 25% of patients who have experienced an acute confusional state have residual cognitive deficits thereafter.

METHODS

This review is based on publications retrieved by a selective search in MEDLINE, PubMed, the Cochrane Library, and in the International Standard Randomised Controlled Trial Number (ISRCTN) registry.

RESULTS

Validated instruments are available for the reliable diagnosis of an acute confusional state, e.g., the Confusion Assessment Method for the ICU (CAM-ICU) for patients in intensive care and the 3D-CAM or CAM-S for patients on regular hospital wards. The prevention and treatment of this condition are achieved primarily by a nonpharmacological, multidimensional approach including early mobilization, reorientation, improvement of sleep, adequate pain relief, and the avoidance of polypharmacy. A meta-analysis has shown that these measures lower the incidence of delirium by 44%. The authors find no basis in the current literature for recommending prophylactic medication, although current data promisingly suggest that the incidence of delirium in surgical patients can be lowered by the perioperative administration of dexmedetomidine (odds ratio 0.35). The pharmaco- therapy of acute confusional states involves a careful choice of drug based on the clinical manifestations in the individual case.

CONCLUSION

The key elements of success in the treatment of acute confusional states in the hospital are adequate prevention, rapid diagnosis, the identification of precipitating factors, and the rapid initiation of both causally oriented and symptom- directed treatment.

Early Postoperative Actigraphy Poorly Predicts Hypoactive Delirium

STUDY OBJECTIVES

Delirium is a postoperative complication accompanied by disturbances in attention, cognition, arousal, and psychomotor activity. Wrist actigraphy has been advocated to study inactivity and inferred sleep patterns during delirium. We hypothesized that altered patterns of motor activity or immobility, reflective of disordered sleep and wakefulness patterns, would serve as predictive markers of hypoactive postoperative delirium.

METHODS

Eighty-four elderly surgical patients were classified into three groups based on the timing of hypoactive delirium following surgery: intact with no delirium throughout postoperative days (POD) 0-5 (n = 51), delirium during POD 0-1 (n = 24), and delirium during POD 2-5 (n = 13). Delirium was detected on daily Confusion Assessment Method evaluations and chart review. Actigraphy measures were calculated from accelerometry signals acquired on the first postoperative day (POD 0, 16:00-23:00) and night (POD 0, 23:00-POD 1, 06:00).

RESULTS

Actigraphy metrics showed substantial interpatient variability. Among the three patient groups, only those without delirium showed greater movement during the day compared to night and also fewer minutes of night immobility (P = .03 and P = .02, Wilcoxon rank-sum tests). These patients were poorly discriminated from those with delirium during either POD 0-1 or POD 2-5, using differences in day and night activity (C-statistic, 95% confidence interval [CI]: 0.66 [0.53-0.79] and C-statistic, 95% CI: 0.71 [0.55-0.87], respectively). Inclusion of low-frequency signals improved performance of immobility measures without affecting those based on activity. Cognitively intact patients during POD 0-5 were distinguished from those with delirium during POD 0-1, based on differences in the number of day and night immobile minutes (C-statistic 0.65, 95% CI: [0.53-0.78]). Actigraphy metrics with the strongest association to delirium incidence were not reliably correlated with an increased risk during POD 0-5, when accounting for patient age, sex, intensive care unit admission, and Charlson Comorbidity Index (adjusted odds ratio of 1.7, 95% CI: [1.0-3.0], P = .09, likelihood ratio test).

CONCLUSIONS

Early postoperative wrist actigraphy metrics that serve as markers of sleep and wakefulness offer limited capacity as sole predictors or markers of hypoactive delirium.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Title: Electroencephalography Guidance of Anesthesia to Alleviate Geriatric Syndromes (ENGAGES) Study; Identifier: NCT02241655; URL: https://clinicaltrials.gov/ct2/show/NCT02241655.

Pharmacologic Treatment of Intensive Care Unit Delirium and the Impact on Duration of Delirium, Length of Intensive Care Unit Stay, Length of Hospitalization, and 28-Day Mortality

OBJECTIVE

To determine whether treatment of delirium affects outcomes.

PATIENTS AND METHODS

A retrospective cohort study of patients admitted to the medical intensive care unit (ICU) from July 1, 2015, through June 30, 2016, was conducted. Patients with ICU delirium, defined by a positive Confusion Assessment Method for the ICU score, were included. Patients were stratified into 4 treatment groups based on exposure to melatonin and antipsychotic agents during ICU stay: no pharmacologic treatment, melatonin only, antipsychotics only, and both melatonin and antipsychotics. A time-dependent cause-specific hazards model with death as a competing risk was used to evaluate the effect of melatonin or antipsychotic drug use for delirium on duration of ICU delirium, length of ICU stay, and length of hospitalization. A logistic regression was used to evaluate 28-day mortality. Covariates significantly associated with exposure to melatonin and antipsychotics were included in the minimally adjusted model. Covariates significantly associated in the minimally adjusted model were included in a final adjusted model.

RESULTS

A total of 449 admissions to the medical ICU were included in the analysis. Exposure to melatonin or antipsychotic agents did not reduce the duration of ICU delirium, ICU/hospital length of stay, or 28-day mortality. However, antipsychotic use only was associated with longer hospitalization.

CONCLUSION

Antipsychotic drugs for the treatment ICU delirium may not provide the benefit documented in earlier literature. Further investigation on patient selection, type of antipsychotic, and dosing is needed.

Delirium pathophysiology: An updated hypothesis of the etiology of acute brain failure

BACKGROUND

Delirium is the most common neuropsychiatric syndrome encountered by clinicians dealing with older adults and the medically ill and is best characterized by 5 core domains: cognitive deficits, attentional deficits, circadian rhythm dysregulation, emotional dysregulation, and alteration in psychomotor functioning.

DESIGN

An extensive literature review and consolidation of published data into a novel interpretation of known pathophysiological causes of delirium.

RESULTS

Available data suggest that numerous pathological factors may serve as precipitants for delirium, each having differential effects depending on patient-specific patient physiological characteristics (substrate). On the basis of an extensive literature search, a newly proposed theory, the systems integration failure hypothesis, was developed to bring together the most salient previously described theories, by describing the various contributions from each into a complex web of pathways-highlighting areas of intersection and commonalities and explaining how the variable contribution of these may lead to the development of various cognitive and behavioral dysfunctions characteristic of delirium. The specific cognitive and behavioral manifestations of the specific delirium picture result from a combination of neurotransmitter function and availability, variability in integration and processing of sensory information, motor responses to both external and internal cues, and the degree of breakdown in neuronal network connectivity, hence the term acute brain failure.

CONCLUSIONS

The systems integration failure hypothesis attempts to explain how the various proposed delirium pathophysiologic theories interact with each other, causing various clinically observed delirium phenotypes. A better understanding of the underlying pathophysiology of delirium may eventually assist in designing better prevention and management approaches.

Defining delirium in idiopathic Parkinson's disease: A systematic review

BACKGROUND

Parkinson's disease patients may be at increased risk of delirium and developing adverse outcomes, such as cognitive decline and increased mortality. Delirium is an acute state of confusion that has overlapping symptoms with Parkinson's dementia, making it difficult to identify. This study aimed to determine the diagnostic criteria, prevalence, management strategies and outcomes of delirium in Parkinson's through a systematic review of the literature.

METHODS

Seven databases were used to identify all articles published before February 2017 comprising two key terms: "Parkinson's Disease" and "delirium". Data were extracted from studies meeting predefined inclusion criteria.

RESULTS

Twenty articles were identified. Delirium prevalence in Parkinson's ranged from 0.3 to 60% depending on setting; a diagnosis of Parkinson's was associated with an increased risk of developing delirium. Delirium was identified/diagnosed using seven different criteria. Delirium may be associated with an increased length of hospital stay and worsening motor symptoms. We did not identify any studies examining the management of delirium in Parkinson's.

DISCUSSION

This review highlights the paucity of well-designed, appropriately powered studies investigating delirium in Parkinson's. The results suggest that delirium is a significant issue in people with Parkinson's and that having delirium may be a risk factor for adverse outcomes, particularly in inpatient settings. Further prospective research is needed to accurately determine the prevalence of delirium in Parkinson's, its management strategies and outcomes, and to evaluate diagnostic criteria to differentiate between the overlapping symptoms of Parkinson's and delirium.

Melatonin and Sleep in Preventing Hospitalized Delirium: A Randomized Clinical Trial

PURPOSE

Studies suggest that melatonin may prevent delirium, a condition of acute brain dysfunction occurring in 20%-30% of hospitalized older adults that is associated with increased morbidity and mortality. We examined the effect of melatonin on delirium prevention in hospitalized older adults while measuring sleep parameters as a possible underlying mechanism.

METHODS

This was a randomized clinical trial measuring the impact of 3 mg of melatonin nightly on incident delirium and both objective and subjective sleep in inpatients age ≥65 years, admitted to internal medicine wards (non-intensive care units). Delirium incidence was measured by bedside nurses using the confusion assessment method. Objective sleep measurements (nighttime sleep duration, total sleep time per 24 hours, and sleep fragmentation as determined by average sleep bout length) were obtained via actigraphy. Subjective sleep quality was measured using the Richards Campbell Sleep Questionnaire.

RESULTS

Delirium occurred in 22.2% (8/36) of subjects who received melatonin vs in 9.1% (3/33) who received placebo (P = .19). Melatonin did not significantly change objective or subjective sleep measurements. Nighttime sleep duration and total sleep time did not differ between subjects who became delirious vs those who did not, but delirious subjects had more sleep fragmentation (sleep bout length 7.0 ± 3.0 vs 9.5 ± 5.3 min; P = .03).

CONCLUSIONS

Melatonin given as a nightly dose of 3 mg did not prevent delirium in non-intensive care unit hospitalized patients or improve subjective or objective sleep.

Melatonin supplementation for the prevention of hospital-associated delirium

Characterized by acute alterations in cognition or consciousness, delirium is a transient neuropsychiatric syndrome that develops in a large percentage of hospitalized patients. Delirium is a robust predictor of increased morbidity, mortality, and health care costs, especially when diagnosed in the critical care setting. Although the exact pathogenesis behind delirium has yet to be defined, disturbances in the sleep-wake cycle are a core feature. Currently, no pharmacologic interventions are recommended for delirium prophylaxis. Due to the role of melatonin in regulating the sleep-wake cycle, its use in delirium has been investigated in recent years. Objective data has shown altered serum levels of melatonin and its precursor, tryptophan, in patients with delirium, further suggesting a correlation between melatonin and delirium. This article examines the available evidence and discusses considerations surrounding melatonin supplementation for the prevention of hospital-associated delirium.

Melatonin and health: an umbrella review of health outcomes and biological mechanisms of action

BACKGROUND

Our aims were to evaluate critically the evidence from systematic reviews as well as narrative reviews of the effects of melatonin (MLT) on health and to identify the potential mechanisms of action involved.

METHODS

An umbrella review of the evidence across systematic reviews and narrative reviews of endogenous and exogenous (supplementation) MLT was undertaken. The Oxman checklist for assessing the methodological quality of the included systematic reviews was utilised. The following databases were searched: MEDLINE, EMBASE, Web of Science, CENTRAL, PsycINFO and CINAHL. In addition, reference lists were screened. We included reviews of the effects of MLT on any type of health-related outcome measure.

RESULTS

Altogether, 195 reviews met the inclusion criteria. Most were of low methodological quality (mean -4.5, standard deviation 6.7). Of those, 164 did not pool the data and were synthesised narratively (qualitatively) whereas the remaining 31 used meta-analytic techniques and were synthesised quantitatively. Seven meta-analyses were significant with P values less than 0.001 under the random-effects model. These pertained to sleep latency, pre-operative anxiety, prevention of agitation and risk of breast cancer.

CONCLUSIONS

There is an abundance of reviews evaluating the effects of exogenous and endogenous MLT on health. In general, MLT has been shown to be associated with a wide variety of health outcomes in clinically and methodologically heterogeneous populations. Many reviews stressed the need for more high-quality randomised clinical trials to reduce the existing uncertainties.

Feasibility of melatonin for prevention of delirium in critically ill patients: a protocol for a multicentre, randomised, placebo-controlled study

INTRODUCTION

Delirium is highly prevalent in the intensive care unit (ICU) and is associated with adverse clinical outcomes. At this time, there is no drug that effectively prevents delirium in critically ill patients. Alterations in melatonin secretion and metabolism may contribute to the development of delirium. Administration of exogenous melatonin has been shown to prevent delirium in non-critically ill surgical and medical patients. This trial will demonstrate the feasibility of a planned multicentre, randomised controlled trial to test the hypothesis that melatonin can prevent delirium in critically ill patients compared with placebo.

METHODS AND ANALYSIS

This feasibility trial is a randomised, 3-arm, placebo-controlled study of melatonin (2 vs 0.5 mg vs placebo, administered for a maximum of 14 days) for the prevention of delirium in critically ill patients. A total of 69 patients aged 18 years and older with an expected ICU length of stay >48 hours will be recruited from 3 Canadian ICUs. The primary outcome is protocol adherence (ie, overall proportion of study drug doses administered in the prescribed administration window). Secondary outcomes include pharmacokinetic parameters, incidence, time to onset, duration of delirium, number of delirium-free days, adverse events, self-reported sleep quality, rest-activity cycles measured by wrist actigraphy, duration of mechanical ventilation, ICU length of stay and mortality. Data will be analysed using an intention-to-treat approach.

ETHICS AND DISSEMINATION

The study has been approved by Health Canada and the research ethics board of each study site. Trial results will be presented at international conferences and published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT02615340: Pre-results.

[Non-withdrawal-related delirium : Evidence on prevention and therapy]

Delirium is a severe and common yet under-diagnosed disorder in the clinical routine. Multiple factors may contribute to the development of delirium, which is associated with increased mortality and high healthcare costs. Treatment of delirium is often provided with delay and limited to pharmacological interventions. This article summarizes the key symptoms for delirium as well as risk factors and highlights the pharmacological and non-pharmacological options for treatment and prevention.

The preventative role of exogenous melatonin administration to patients with advanced cancer who are at risk of delirium: study protocol for a randomized controlled trial

BACKGROUND

Delirium is a very common and distressing neuropsychiatric syndrome in palliative care. Increasing age, the presence of dementia and advanced cancer are well-known predisposing risk factors for delirium development. Sleep-wake cycle disturbance is frequently seen during delirium and melatonin has a pivotal role in the regulation of circadian rhythms. Current evidence across various settings suggests a potential preventative role for melatonin in patients at risk of delirium, but no studies are currently reported in patients with advanced cancer. The aim of this article is to describe the design of a feasibility study that is being conducted to inform a larger randomized, placebo-controlled, double-blind trial (RCT) to evaluate the role of exogenously administered melatonin in preventing delirium in patients with advanced cancer.

METHODS/DESIGN

Adult patients with a cancer diagnosis who are admitted to the palliative care unit will be randomized into a treatment or placebo group. The pharmacological intervention consists of a single daily dose of immediate-release melatonin (3 mg) at 21:00 ± 1 h, from day 1 to day 28 of admission. The primary objective of this initial study is to assess the feasibility of conducting the proposed RCT by testing recruitment and retention rates, appropriateness of study outcome measures, acceptability of study procedures and effectiveness of the blinding process. The primary outcome measure of the proposed larger RCT is time to first inpatient incident episode of delirium. We also plan to collect data on incident rates of delirium and patient-days of delirium, adjusting for length of admission.

DISCUSSION

The outcomes of this feasibility study will provide information on recruitment and retention rates, protocol violation frequency, effectiveness of the blinding process, acceptability of the study procedures, and safety of the proposed intervention. This will inform the design of a fully powered randomized controlled trial to evaluate the preventative role of melatonin administration in patients with advanced cancer.

TRIAL REGISTRATION

Registered with ClinicalTrials.gov: NCT02200172 Registered on 21 July 2014. Health Canada protocol number: BRI-MELAT-2013 (Final approved protocol version (Version 3): 18 June 2014) (Notice of Amended Authorization (NOA) received 14 November 2014).