Anticholinergic Medication Use and Transition to Delirium in Critically Ill Patients: A Prospective Cohort 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.

Implementation of Evidence-Based International Recommendations Reduces Postoperative Delirium Rate in Patients Undergoing Cardiac Surgery or Interventions: A System-Based Quality Improvement Study

Background

Delirium is a frequent and serious complication of cardiac procedures that can lead to serious long-term health restrictions. As primary prevention is more effective in reducing rate of delirium than the therapy itself, this study aimed to investigate the effect of a multidisciplinary delirium prevention bundle on the postoperative delirium rate in patients undergoing cardiac procedures.

Methods

In this system-based quality improvement study, a four-component delirium prevention bundle was implemented in patients undergoing cardiac procedures at a single high-volume center. The program included preoperative delirium risk stratification, multidisciplinary education of consensus guidelines, written memory aids, and post-anesthetic visits with delirium screening until postoperative day three.

Results

Overall, 234 patients were included and analyzed during the 6-month study period. The overall delirium incidence rate was 12.4%. After the first 3-month baseline implementation period, the delirium rate was 17.2%, compared with 7.6% (p = 0.026) after implementation of the delirium prevention bundle. Multivariate analysis revealed independent risk factors such as age [adjusted odds ratio (OR): 1.046; 95% confidence interval (CI): 1.002-1.092; p = 0.042], double valve surgery [adjusted OR: 13.1; 95% CI: 3.240-52.974; p < 0.0001], and peripheral artery disease [adjusted OR: 8.131; 95% CI: 2.336-28.306; p < 0.001]. Hospital stay was significantly longer in patients with delirium [median 13 (12-19.5) versus 12 (11-14) days, p = 0.009].

Conclusions

This multidisciplinary system-based quality improvement study demonstrated a beneficial effect on the delirium rate after the implementation of a four-component delirium prevention bundle in patients undergoing cardiac surgery or intervention. Furthermore, multivariate analysis revealed important independent risk factors for delirium development. This might improve early risk stratification and strategies for this high-risk patient collective.

Pharmacotherapy assessment and adverse drug reactions in older patients admitted to intensive care

INTRODUCTION

Older patients are more susceptible to medication use, and physiological changes resulting from aging and organic dysfunctions presented by critically ill patients may alter the pharmacokinetic or pharmacodynamic behavior. Thus, critically ill older people present greater vulnerability to the occurrence of pharmacotherapeutic problems.

OBJECTIVE

To evaluate pharmacotherapy and the development of potential adverse drug reactions (ADRs) in older patients admitted to an intensive care unit (ICU).

METHOD

A cohort study was conducted in an ICU for adults of a Brazilian University Hospital during a 12-month period. The patients' pharmacotherapy was evaluated daily, considering the occurrence of ADRs and drug-drug interactions (DDIs), the use of potentially inappropriate medications (PIMs) for older people, and the pharmacotherapy anticholinergic burden (ACB). A trigger tool was used for active search of ADRs, with subsequent causality evaluation. PIM use was evaluated by means of the Beers criteria and the STOPP/START criteria. The ABC scale was employed to estimate ACB. The Micromedex® and Drugs.com® medication databases were employed to evaluate the DDIs.

RESULTS

The sample of this study consisted of 41 patients, with a mean age of 66.8 years old (±5.2). The 22 triggers used assisted in identifying 15 potential ADRs, and 26.8% of the patients developed them. The mean estimated ACB score was 3.0 (±1.8), and the patients used 3.1 (±1.4) and 3.3 (±1.6) PIMs according to the Beers and the STOPP criteria, respectively. A total of 672 DDIs were identified, with a mean of 16.8 (±9.5) DDIs/patient during ICU hospitalization. Our findings show an association between occurrence of ADRs in the ICU and polypharmacy (p=.03) and DDIs (p=.007), corroborating efforts for rational medication use as a preventive strategy.

CONCLUSIONS

Using tools to evaluate the pharmacotherapy for older people in intensive care can assist in the recognition and prevention of pharmacotherapeutic problems, with emphasis on the identification of ADRs through the observation of triggers and subsequent causality analysis.

Anticholinergic Burden and Xerostomia in Critical Care Settings

BACKGROUND

Although previous studies have established the association of medications with anticholinergic adverse effects and xerostomia, anticholinergic burden and xerostomia in critical care settings are poorly characterized. The objective of this study was to determine the impact of medication burdens associated with anticholinergic adverse effects, particularly the occurrence of xerostomia (dry mouth) in a critical care setting. In addition, this study explored the correlation between the timing of the first instance of xerostomia and the administration timing of medication known to have anticholinergic adverse effects.

METHODS

A retrospective case-control study was used with the MIMIC (Medical Information Mart for Intensive Care) III database. The MIMIC-III clinical database is a publicly available, deidentified, health-related database with more than 40 000 patients in critical care units from 2001 to 2012. Cases of xerostomia (n = 1344) were selected from clinical notes reporting "dry mouth," "xerostomia," or evidence of pharmacological treatment for xerostomia; control (n = 4032) was selected using the propensity analysis with 1:3 matching on covariates (eg, age, sex, race, ethnicity, and length of stay). The anticholinergic burden was quantified as the cumulative effect of anticholinergic activities using the Anticholinergic Burden Scale.

RESULTS

Anticholinergic burden significantly differed between xerostomia patients and control subjects (P = .04). The length of stay was a statistically significant factor in xerostomia. The probability of developing the symptom of xerostomia within 24 hours was .95 (95%) for patients of xerostomia.

CONCLUSIONS

Anticholinergic Burden Scale is associated with xerostomia in the critical care setting, particularly within 24 hours after admission. It is crucial to carefully evaluate alternative options for medications that may have potential anticholinergic adverse effects. This evaluation should include assessing the balance between the benefits and harms, considering the probability of withdrawal reactions, and prioritizing deprescribing whenever feasible within the initial 24-hour period.

Non-Neuronal Acetylcholinesterase Activity Shows Limited Utility for Early Detection of Sepsis

(1) Background: Sepsis is a severe systemic inflammatory condition characterized by rapid clinical deterioration and organ dysfunction. The cholinergic system has been implicated in modulating the inflammatory response. Acetylcholinesterase (AChE), an enzyme primarily responsible for the hydrolysis of acetylcholine, has been proposed as a potential early indicator of sepsis onset. However, the exact role of non-neuronal AChE activity in sepsis and its correlation with disease severity and patient outcomes remain unclear. This study aimed to investigate the involvement of AChE activity in sepsis and evaluate its association with disease severity and clinical outcomes. (2) Methods: A prospective study included 43 septic patients. AChE activity was measured at sepsis detection, as well as 7 and 28 days later. Inflammatory biomarkers, disease severity scores, and patient outcomes were evaluated. (3) Results: AChE activity remained stable for 7 days and decreased at 28 days. However, there was no correlation between initial AChE activity and inflammatory biomarkers, disease severity scores, ICU stay, or hospital stay. (4) Conclusions: Non-neuronal AChE activity may not reliably indicate early sepsis or predict disease severity.

Increased Enzymatic Activity of Acetylcholinesterase Indicates the Severity of the Sterile Inflammation and Predicts Patient Outcome following Traumatic Injury

Traumatic injury induces sterile inflammation, an immune response often associated with severe organ dysfunction. The cholinergic system acts as an anti-inflammatory in injured patients. Acetylcholinesterase (AChE), an enzyme responsible for the hydrolysis of acetylcholine, plays an essential role in controlling cholinergic activity. We hypothesized that a change in the AChE activity might indicate the severity of the traumatic injury. This study included 82 injured patients with an Injury Severity Score (ISS) of 4 or above and 40 individuals without injuries. Bedside-measured AChE was obtained on hospital arrival, followed by a second measurement 4-12 h later. C-reactive protein (CRP), white blood cell count (WBCC), and Sequential Organ Failure Assessment (SOFA) score were simultaneously collected. Injured patients showed an early and sustained increase in AChE activity. CRP remained unaffected at hospital admission and increased subsequently. Initially elevated WBCC recovered 4-12 h later. AChE activity directly correlated with the ISS and SOFA scores and predicted the length of ICU stay when measured at hospital admission. An early and sustained increase in AChE activity correlated with the injury severity and could predict the length of ICU stay in injured patients, rendering this assay a complementary diagnostic and prognostic tool at the hand of the attending clinician in the emergency unit.

Evaluation of the association of anticholinergic burden and delirium in older hospitalised patients - A cohort study comparing 19 anticholinergic burden scales

AIMS

A recent review identified 19 anticholinergic burden scales (ABSs) but no study has yet compared the impact of all 19 ABSs on delirium. We evaluated whether a high anticholinergic burden as classified by each ABS is associated with incident delirium.

METHOD

We performed a retrospective cohort study in a Swiss tertiary teaching hospital using data from 2015-2018. Included were patients aged ≥65, hospitalised ≥48 hours with no stay >24 hours in intensive care. Delirium was defined twofold: (i) ICD-10 or CAM and (ii) ICD-10 or CAM or DOSS. Patients' cumulative anticholinergic burden score, calculated within 24 hours after admission, was classified using a binary (<3: low, ≥3: high burden) and a categorical approach (0: no, 0.5-3: low, ≥3: high burden). Association was analysed using multivariable logistic regression.

RESULTS

Over 25 000 patients (mean age 77.9 ± 7.6 years) were included. Of these, (i) 864 (3.3%) and (ii) 2770 (11.0%) developed delirium. Depending on the evaluated ABS, 4-63% of the patients were exposed to at least one anticholinergic drug. Out of 19 ABSs, (i) 14 and (ii) 16 showed a significant association with the outcomes. A patient with a high anticholinergic burden score had odds ratios (ORs) of 1.21 (95% confidence interval [CI]: 1.03-1.42) to 2.63 (95% CI: 2.28-3.03) for incident delirium compared to those with low or no burden.

CONCLUSION

A high anticholinergic burden within 24 hours after admission was significantly associated with incident delirium. Although prospective studies need to confirm these results, discontinuing or substituting drugs with a score of ≥3 at admission might be a targeted intervention to reduce incident delirium.

Anticholinergic Drug Exposure Increases the Risk of Delirium in Older Patients Undergoing Elective Surgery

Introduction

Postoperative delirium (POD) is a common and serious adverse event of surgery in older people. Because of its great impact on patients' safety and quality of life, identification of modifiable risk factors could be useful. Although preoperative medication intake is assumed to be an important modifiable risk factor, the impact of anticholinergic drugs on the occurrence of POD seems underestimated in elective surgery. The aim of this study was to investigate the association between preoperative anticholinergic burden and POD. We hypothesized that a high preoperative anticholinergic burden is an independent, potentially modifiable predisposing and precipitating factor of POD in older people.

Methods

Between November 2017 and April 2019, 1,470 patients of 70 years and older undergoing elective orthopedic, general, cardiac, or vascular surgery were recruited in the randomized, prospective, multicenter PAWEL trial. Anticholinergic burden of a sub-cohort of 899 patients, who did not receive a multimodal intervention for preventing POD, was assessed by two different tools at hospital admission: The established Anticholinergic Risk Scale (ARS) and the recently developed Anticholinergic Burden Score (ABS). POD was detected by confusion assessment method (CAM) and a validated post discharge medical record review. Logistic regression analyses were performed to evaluate the association between anticholinergic burden and POD.

Results

POD was observed in 210 of 899 patients (23.4%). Both ARS and ABS were independently associated with POD. The association persisted after adjustment for relevant confounding factors such as age, sex, comorbidities, preoperative cognitive and physical status, number of prescribed drugs, surgery time, type of surgery and anesthesia, usage of heart-lung-machine, and treatment in intensive care unit. If a patient was taking one of the 56 drugs listed in the ABS, risk for POD was 2.7-fold higher (OR = 2.74, 95% CI = 1.55–4.94) and 1.5-fold higher per additional point on the ARS (OR = 1.54, 95% CI = 1.15–2.02).

Conclusion

Preoperative anticholinergic drug exposure measured by ARS or ABS was independently associated with POD in older patients undergoing elective surgery. Therefore, identification, discontinuation or substitution of anticholinergic medication prior to surgery may be a promising approach to reduce the risk of POD in older patients.

Delirium and Its Pharmacological Causes in Older People, Part 1

Delirium is a syndrome that can arise from many causes or underlying conditions, and though it has been reported in younger patients, it is more prevalent in older people, though it can occur in other age groups as well. Identifying delirium is challenging in older people because of the coexistence of underlying dementia or depression, which may further complicate the presentation. Drug-induced delirium is one of the major causes of delirium, and evaluation of this potential cause or contribution is an important component of the evaluation process, since it can lead to poor patient outcomes. This article will review the epidemiology, pathophysiology, evaluation, diagnostic process, and causes of delirium in older people, with a focus on the pharmacological causes.

Opioid Use Increases the Risk of Delirium in Critically Ill Adults Independently of Pain

Rationale: It is unclear whether opioid use increases the risk of ICU delirium. Prior studies have not accounted for confounding, including daily severity of illness, pain, and competing events that may preclude delirium detection.Objectives: To evaluate the association between ICU opioid exposure, opioid dose, and delirium occurrence.Methods: In consecutive adults admitted for more than 24 hours to the ICU, daily mental status was classified as awake without delirium, delirium, or unarousable. A first-order Markov model with multinomial logistic regression analysis considered four possible next-day outcomes (i.e., awake without delirium, delirium, unarousable, and ICU discharge or death) and 11 delirium-related covariables (baseline: admission type, age, sex, Acute Physiology and Chronic Health Evaluation IV score, and Charlson comorbidity score; daily: ICU day, modified Sequential Organ Failure Assessment, ventilation use, benzodiazepine use, and severe pain). This model was used to quantify the association between opioid use, opioid dose, and delirium occurrence the next day.Measurements and Main Results: The 4,075 adults had 26,250 ICU days; an opioid was administered on 57.0% (n = 14,975), severe pain occurred on 7.0% (n = 1,829), and delirium occurred on 23.5% (n = 6,176). Severe pain was inversely associated with a transition to delirium (odds ratio [OR] 0.72; 95% confidence interval [CI], 0.53-0.97). Any opioid administration in awake patients without delirium was associated with an increased risk for delirium the next day [OR, 1.45; 95% CI, 1.24-1.69]. Each daily 10-mg intravenous morphine-equivalent dose was associated with a 2.4% increased risk for delirium the next day.Conclusions: The receipt of an opioid in the ICU increases the odds of transitioning to delirium in a dose-dependent fashion.

Profiling Delirium Progression in Elderly Patients via Continuous-Time Markov Multi-State Transition Models

Poor recognition of delirium among hospitalized elderlies is a typical challenge for health care professionals. Considering methodological insufficiency for assessing time-varying diseases, a continuous-time Markov multi-state transition model (CTMMTM) was used to investigate delirium evolution in elderly patients. This is a longitudinal observational study performed in September 2016 in an Italian hospital. Change of delirium states was modeled according to the 4AT score. A Cox model (CM) and a CTMMTM were used for identifying factors affecting delirium onset both with a two-state and three-state model. In this study, 78 patients were enrolled and evaluated for 5 days. Both the CM and the CTMMTM show that urine catheter (UC), aging, drugs, and invasive devices (ID) are risk factors for delirium onset. The CTMMTM model shows that transition from no-delirium/cognitive impairment to delirium was associated with aging (HR = 1.14; 95%CI, 1.05, 1.23) and neuroleptics (HR = 4.3; 1.57, 11.77), dopaminergic drugs (HR = 3.89; 1.2, 12.6), UC (HR = 2.92; 1.09, 7.79) and ID (HR = 1.67; 103, 2.71). These results are confirmed by the multivariable model. Aging, ID, antibiotics, drugs affecting the central nervous system, and absence of moving ability are identified as the significant predictors of delirium. Additionally, it seems that modeling with CTMMTM may show associations that are not directly detectable with the traditional CM.

Association Between Incident Delirium Treatment With Haloperidol and Mortality in Critically Ill Adults

OBJECTIVES

Haloperidol is commonly administered in the ICU to reduce the burden of delirium and its related symptoms despite no clear evidence showing haloperidol helps to resolve delirium or improve survival. We evaluated the association between haloperidol, when used to treat incident ICU delirium and its symptoms, and mortality.

DESIGN

Post hoc cohort analysis of a randomized, double-blind, placebo-controlled, delirium prevention trial.

SETTING

Fourteen Dutch ICUs between July 2013 and December 2016.

PATIENTS

One-thousand four-hundred ninety-five critically ill adults free from delirium at ICU admission having an expected ICU stay greater than or equal to 2 days.

INTERVENTIONS

Patients received preventive haloperidol or placebo for up to 28 days until delirium occurrence, death, or ICU discharge. If delirium occurred, treatment with open-label IV haloperidol 2 mg tid (up to 5 mg tid per delirium symptoms) was administered at clinician discretion.

MEASUREMENTS AND MAIN RESULTS

Patients were evaluated tid for delirium and coma for 28 days. Time-varying Cox hazards models were constructed for 28-day and 90-day mortality, controlling for study-arm, delirium and coma days, age, Acute Physiology and Chronic Health Evaluation-II score, sepsis, mechanical ventilation, and ICU length of stay. Among the 1,495 patients, 542 (36%) developed delirium within 28 days (median [interquartile range] with delirium 4 d [2-7 d]). A total of 477 of 542 (88%) received treatment haloperidol (2.1 mg [1.0-3.8 mg] daily) for 6 days (3-11 d). Each milligram of treatment haloperidol administered daily was associated with decreased mortality at 28 days (hazard ratio, 0.93; 95% CI, 0.91-0.95) and 90 days (hazard ratio, 0.97; 95% CI, 0.96-0.98). Treatment haloperidol administered later in the ICU course was less protective of death. Results were stable by prevention study-arm, predelirium haloperidol exposure, and haloperidol treatment protocol adherence.

CONCLUSIONS

Treatment of incident delirium and its symptoms with haloperidol may be associated with a dose-dependent improvement in survival. Future randomized trials need to confirm these results.

Association Between Dexamethasone and Delirium in Critically Ill Patients: A Retrospective Cohort Study of a Large Clinical Database

BACKGROUND

Delirium is a common complication in intensive care unit (ICU) patients, and it can significantly increase the length of hospital stay and cost. Dexamethasone is widely used in various inflammatory diseases and must be used with caution in critically ill patients. Previous studies have shown that the effect of corticosteroid use on the development of delirium in critically ill patients is still controversial, and there is inconclusive conclusion about the effect of dexamethasone on delirium in such patients. Therefore, this study aimed to confirm the effect of dexamethasone use and the dose on the incidence of delirium and patient prognosis in critically ill patients through a large cohort study.

METHODS

A retrospective cohort study was conducted using data extracted from the Medical Information Mart for Intensive Care III database, which is a large and freely available database of all 46,476 patients who visited Beth Israel Deaconess Medical Center in Boston, Massachusetts, USA and were admitted to the ICU between 2001 and 2012. The primary outcome was the development of delirium, using multivariate logistic regression analysis to reveal the relationship between dexamethasone and delirium. Secondary endpoints were in-hospital mortality, ICU mortality, total length of stay, and length of ICU stay, and the relationship between dexamethasone and prognosis was assessed with Cox proportional hazards models. Propensity score matching with 1:1 grouping was used to eliminate the effect of confounders on both cohorts. The locally weighted scatter plot smoothing technique was used to investigate the dose correlation between dexamethasone and outcomes, subgroup analysis was used to account for heterogeneity, and different correction models and propensity matching analysis were used to eliminate potential confounders.

RESULTS

Finally, 38,509 patients were included, and 2204 (5.7%) used dexamethasone. No significant statistical difference was observed in basic demographic information after propensity score matching between the two study groups. A significantly higher incidence of delirium (5.0% versus 3.4%, P < 0.001), increased in-hospital mortality (14.9% versus 10.3%, P < 0.001), ICU mortality (9.0% versus 7.5%, P = 0.008), and longer length of stay and ICU stay were observed in patients taking dexamethasone compared with those not taking dexamethasone. Multivariate logistic and Cox regression analyses confirmed that dexamethasone was significantly associated with delirium (adjusted odds ratio = 1.48, 95% confidence interval [CI] = 1.09-2.00, P = 0.012), in-hospital mortality (adjusted hazard ratio = 1.19, 95% CI = 1.02-1.40, P = 0.032), and ICU mortality (adjusted hazard ratio = 1.62, 95% CI = 1.22-2.15, P = 0.001). Compared with critically ill patients using high-dose dexamethasone, the risk of delirium was lower in the dose less than the 10 mg group, and patients using 10-14 mg may be associated with a lower risk of in-hospital death and the least ICU mortality, length of hospital stay, and ICU stay.

CONCLUSIONS

This study demonstrated that the use of dexamethasone in critically ill patients exacerbated the occurrence of delirium while increasing the risk of in-hospital death, ICU death, and length of hospital stay, with a lower risk of delirium and a shorter total length of hospital stay with low-dose dexamethasone than with larger doses.

Haloperidol, clonidine and resolution of delirium in critically ill patients: a prospective cohort study

Purpose

Haloperidol and clonidine are commonly used to treat agitation in delirious intensive care unit (ICU) patients, but it is unclear whether these agents may shorten the duration of delirium. The objective of this study was to determine whether haloperidol, clonidine, or their combined administration to delirious ICU patients results in delirium resolution.

Methods

This was a cohort study on a mixed ICU, excluding patients with a primary neurological disorder. The main outcome was the probability of delirium resolution, using propensity score matching and Markov multinomial logistic regression models for daily transitions. Secondary outcomes were delirium duration, number of delirium days, ventilation days, length of stay in the ICU and hospital, and ICU mortality.

Results

A total of 3614 patients were included (1165 delirious [32%]; 2449 non-delirious [68%]). Delirium occurred on 4708 (18.9%) of 24,906 days. The probability of delirium resolution was lower in delirious patients who received haloperidol (OR 0.47, 95% CI 0.39–0.57), clonidine (OR 0.78, 95% CI 0.63–0.97), or both (OR 0.45, 95% CI 0.36–0.56) compared to untreated delirious patients. Delirious patients who received haloperidol, clonidine, or both had generally longer delirium duration, more delirium and ventilation days, and spent more time in the ICU and in hospital than untreated delirious patients. These agents had no effect on ICU mortality.

Conclusion

Haloperidol and clonidine use in delirious ICU patients may be associated with reduced probability of delirium resolution. This finding, however, merits further investigation given inherent limitations of this observational analysis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00134-021-06355-9.

Quality of anticholinergic burden scales and their impact on clinical outcomes: a systematic review

PURPOSE

Older people are at risk of anticholinergic side effects due to changes affecting drug elimination and higher sensitivity to drug's side effects. Anticholinergic burden scales (ABS) were developed to quantify the anticholinergic drug burden (ADB). We aim to identify all published ABS, to compare them systematically and to evaluate their associations with clinical outcomes.

METHODS

We conducted a literature search in MEDLINE and EMBASE to identify all published ABS and a Web of Science citation (WoS) analysis to track validation studies implying clinical outcomes. Quality of the ABS was assessed using an adapted AGREE II tool. For the validation studies, we used the Newcastle-Ottawa Scale and the Cochrane tool Rob2.0. The validation studies were categorized into six evidence levels based on the propositions of the Oxford Center for Evidence-Based Medicine with respect to their quality. At least two researchers independently performed screening and quality assessments.

RESULTS

Out of 1297 records, we identified 19 ABS and 104 validations studies. Despite differences in quality, all ABS were recommended for use. The anticholinergic cognitive burden (ACB) scale and the German anticholinergic burden scale (GABS) achieved the highest percentage in quality. Most ABS are validated, yet validation studies for newer scales are lacking. Only two studies compared eight ABS simultaneously. The four most investigated clinical outcomes delirium, cognition, mortality and falls showed contradicting results.

CONCLUSION

There is need for good quality validation studies comparing multiple scales to define the best scale and to conduct a meta-analysis for the assessment of their clinical impact.

Stratified delirium risk using prescription medication data in a state-wide cohort

OBJECTIVE

Delirium is a common condition associated with increased morbidity and mortality. Medication side effects are a possible source of modifiable delirium risk and provide an opportunity to improve delirium predictive models. This study characterized the risk for delirium diagnosis by applying a previously validated algorithm for calculating central nervous system adverse effect burden arising from a full medication list.

METHOD

Using a cohort of hospitalized adult (age 18-65) patients from the Massachusetts All-Payers Claims Database, we calculated medication burden following hospital discharge and characterized risk of new coded delirium diagnosis over the following 90 days. We applied the resulting model to a held-out test cohort.

RESULTS

The cohort included 62,180 individuals of whom 1.6% (1019) went on to have a coded delirium diagnosis. In the training cohort (43,527 individuals), the medication burden feature was positively associated with delirium diagnosis (OR = 5.75, 95% CI 4.34-7.63) and this association persisted (aOR = 1.95; 1.31-2.92) after adjusting for demographics, clinical features, prescribed medications, and anticholinergic risk score. In the test cohort, the trained model produced an area under the curve of 0.80 (0.78-0.82). This performance was similar across subgroups of age and gender.

CONCLUSION

Aggregating brain-related medication adverse effects facilitates identification of individuals at high risk of subsequent delirium diagnosis.

Quality of anticholinergic burden scales and their impact on clinical outcomes: a systematic review

Purpose

Older people are at risk of anticholinergic side effects due to changes affecting drug elimination and higher sensitivity to drug’s side effects. Anticholinergic burden scales (ABS) were developed to quantify the anticholinergic drug burden (ADB). We aim to identify all published ABS, to compare them systematically and to evaluate their associations with clinical outcomes.

Methods

We conducted a literature search in MEDLINE and EMBASE to identify all published ABS and a Web of Science citation (WoS) analysis to track validation studies implying clinical outcomes. Quality of the ABS was assessed using an adapted AGREE II tool. For the validation studies, we used the Newcastle-Ottawa Scale and the Cochrane tool Rob2.0. The validation studies were categorized into six evidence levels based on the propositions of the Oxford Center for Evidence-Based Medicine with respect to their quality. At least two researchers independently performed screening and quality assessments.

Results

Out of 1297 records, we identified 19 ABS and 104 validations studies. Despite differences in quality, all ABS were recommended for use. The anticholinergic cognitive burden (ACB) scale and the German anticholinergic burden scale (GABS) achieved the highest percentage in quality. Most ABS are validated, yet validation studies for newer scales are lacking. Only two studies compared eight ABS simultaneously. The four most investigated clinical outcomes delirium, cognition, mortality and falls showed contradicting results.

Conclusion

There is need for good quality validation studies comparing multiple scales to define the best scale and to conduct a meta-analysis for the assessment of their clinical impact.

Electronic supplementary material

The online version of this article (10.1007/s00228-020-02994-x) contains supplementary material, which is available to authorized users.

Approaches to Optimize Medication Data Analysis in Clinical Cohort Studies

OBJECTIVES

Methods for pharmacoepidemiologic studies of large-scale data repositories are established. Although clinical cohorts of older adults often contain critical information to advance our understanding of medication risk and benefit, the methods best suited to manage medication data in these samples are sometimes unclear and their degree of validation unknown. We sought to provide researchers, in the context of a clinical cohort study of delirium in older adults, with guidance on the methodological tools to use data from clinical cohorts to better understand medication risk factors and outcomes.

DESIGN

Prospective cohort study.

SETTING

The Successful Aging After Elective Surgery (SAGES) prospective cohort.

PARTICIPANTS

A total of 560 older adults (aged ≥70 years) without dementia undergoing elective major surgery.

MEASUREMENTS

Using the SAGES clinical cohort, methods used to characterize medications were identified, reviewed, analyzed, and distinguished by appropriateness and degree of validation for characterizing pharmacoepidemiologic data in smaller clinical data sets.

RESULTS

Medication coding is essential; the American Hospital Formulary System, most often used in the United States, is not preferred over others. Use of equivalent dosing scales (e.g., morphine equivalents) for a single medication class (e.g., opioids) is preferred over multiclass analgesic equivalency scales. Medication aggregation from the same class (e.g., benzodiazepines) is well established; the optimal prevalence breakout for aggregation remains unclear. Validated scale(s) to combine structurally dissimilar medications (e.g., anticholinergics) should be used with caution; a lack of consensus exists regarding the optimal scale. Directed acyclic graph(s) are an accepted method to conceptualize causative frameworks when identifying potential confounders. Modeling-based strategies should be used with evidence-based, a priori variable-selection strategies.

CONCLUSION

As highlighted in the SAGES cohort, the methods used to classify and analyze medication data in clinically rich cohort studies vary in the rigor by which they have been developed and validated.

Anticholinergic drug exposure at intensive care unit admission affects the occurrence of delirium. A prospective cohort study

BACKGROUND

Anticholinergic drugs may increase the risk of delirium in non-critically ill patients, but it is unclear whether exposure to these drugs is also a risk factor for Intensive Care Unit (ICU) delirium. In this study the hypothesis was tested that anticholinergic drug exposure at ICU admission increases the risk to develop delirium during ICU stay, particularly in patients with advanced age and severe sepsis.

METHODS

A prospective cohort study was performed in the mixed 32-bed medical-surgical ICU of the University Medical Center Utrecht, the Netherlands in the period from January 2011 till June 2013. Included were nonneurological patients that were consecutively admitted for more than 24 hours. The presence of delirium was evaluated each day using a validated algorithm based on the Confusion Assessment Method for the ICU (CAM-ICU), the initiation of delirium treatment as well as chart review by researchers. Anticholinergic drug exposure at ICU admission was assessed using the Anticholinergic Drug Scale (ADS). To evaluate the association between anticholinergic drug exposure at ICU admission and the risk of developing delirium, we performed multivariable competing risk Cox proportional hazard analysis corrected for confounding factors.

RESULTS

Approximately half (47%, n=513) of the 1090 included patients developed delirium during ICU admission. The absolute risk for delirium development increased with more anticholinergic drug exposure: 42% in patients with ADS score=0, 49% in patients with ADS score=1, and 53% in patients with ADS higher than 1. Taking competing events (death and discharge) and potential confounding factors into account, the subdistribution hazard ratio (SHR) was 1.13 (95% CI: 0.91-1.40) for ADS score=1 point and 1.35 (95% CI: 1.09-1.68) for ADS ≥2 compared with an ADS score=0 (no anticholinergic drug exposure). The effect was strongest during the first days of ICU admittance and was strongest in patients above 65 year without severe sepsis and/or septic shock (SHR 2.15, 95% CI 1.43-3.25).

CONCLUSIONS

Anticholinergic drug exposure at ICU admission increases the risk of delirium in critically ill patients. This effect was most pronounced in patients older than 65 years without severe sepsis and/or septic shock, and declining over time.

Anticholinergic Drug Burden and Delirium: A Systematic Review

OBJECTIVES

To investigate the association between anticholinergic drug burden (ADB), measured with anticholinergic drug scales, and delirium and delirium severity.

DESIGN

Systematic review.

SETTING AND PARTICIPANTS

All available studies.

METHODS

A systematic literature search was performed in Medline, Embase, PsycINFO, Web of Science, CINAHL, Cochrane library, and Google Scholar. Studies evaluating the association between ADB (measured as a total score) and delirium or delirium severity, published in English, were eligible for inclusion.

RESULTS

Sixteen studies, including 148,756 persons, were included. Fifteen studies investigated delirium. ADB was measured with the Anticholinergic Risk Scale (ARS, n = 5), the Anticholinergic Cognitive Burden Scale (ACB, n = 6), the list of Chew (n = 1), the Anticholinergic Drug Scale (ADS, n = 5), a modified version of the ARS (n = 1), and a modified version of the ACB (n = 1). A high ADB, measured with the ARS, was associated with delirium (5/5). Also with the modified version of the ARS and ACB, an association was found between a high ADB and delirium during 3-month (1/1) and 1-year follow-up (1/1), respectively. When ADB was assessed with other scales, the results were inconclusive, with only 1 positive association for the ACB (1/6) and ADS (1/5) each. The possible association between ADB and delirium severity has also been investigated (ADS n = 2, Summers Drug Risk Number n = 1). One study found an association between a high ADB, measured with the ADS, and an increase in severity of delirium.

CONCLUSIONS AND IMPLICATIONS

ADB assessed with the ARS is consistently associated with delirium. The association found between the modified versions of the ARS and ACB and delirium needs confirmation. When ADB was assessed with other scales, the findings were inconclusive. The current findings suggest that the ARS might be a useful tool to identify patients at increased risk for delirium.

Cholinesterases and Anticholinergic Medications in Postoperative Pediatric Delirium

OBJECTIVES

To describe the relationships between anticholinergic drug exposure, cholinesterase enzyme activity, inflammation, and the development of postoperative delirium in children.

DESIGN

Single-center prospective cohort study.

SETTING

Twenty-two bed PICU in a tertiary-care academic medical center in Germany.

PATIENTS

A consecutive cohort of children admitted after major elective surgery.

INTERVENTIONS

Children were screened for delirium bid over 5 consecutive postoperative days. Acetylcholinesterase and butyrylcholinesterase plasma activity levels were measured prior to surgery and once daily during the 5 day study period. Number of anticholinergic drugs and Anticholinergic Drug Scale score were calculated for each patient.

MEASUREMENTS AND MAIN RESULTS

Ninety-three children (age range, 0-17 yr) were included. The number of anticholinergic drugs as well as the Anticholinergic Drug Scale score were significantly correlated with development of postoperative delirium, independently of disease severity. Baseline cholinesterase enzyme levels did not differ between patients who did and did not develop postoperative delirium. Butyrylcholinesterase levels, but not acetylcholinesterase levels, dropped by 33% postoperatively, independent of the presence of postoperative delirium. Postoperative butyrylcholinesterase levels were inversely related to number of anticholinergic drugs, Anticholinergic Drug Scale score, and C-reactive protein levels.

CONCLUSIONS

Anticholinergic drug exposure was related to development of postoperative delirium in this cohort, with demonstration of a dose-response relationship. As there are alternative options available for many of these medications, it may be reasonable to avoid anticholinergic exposure in the PICU whenever possible.

Exposure to Anticholinergic Medications in Pediatric Severe Sepsis and Feasibility of Delirium Screening

In sepsis, anticholinergic dysregulation may result in encephalopathy or delirium during severe illness, either as a result of central inflammation or because of exposure to medications with anticholinergic activity. In this retrospective study, we determined the magnitude of anticholinergic drug exposure in 75 children with severe sepsis. We found that exposure over the first 5 days was high-median (interquartile range) daily anticholinergic drug scale score 4 (2-5)-and associated with higher vasoactive scores and death. We conclude that anticholinergic drug exposure is significant in severe sepsis, which means it may be a modifiable factor that should be studied further.

Anticholinergic Drugs in Geriatric Psychopharmacology

Drugs with anticholinergic action are widely prescribed in the elderly population due to their potential clinical benefits. However, these benefits are limited by adverse effects which may be serious in particular circumstances. This review presents different aspects of the use of anticholinergics in old age with a focus in psychogeriatric patients. We critically review published data on benefits and disadvantages of anticholinergics, which are often controversial. Prevalence, pathophysiology and measurement methods of the anticholinergic action of drugs are discussed. We also present the most important drawbacks resulting from its use, including effects on cognition in healthy and cognitively impaired people, in aged schizophrenia patients, emergence of delirium and psychiatric symptoms, influence in functionality, hospitalization, institutionalization and mortality, and the potential benefits and limitations of their discontinuation. Finally, we suggest practical recommendations for the safe use of anticholinergics in clinical conditions affecting elderly patients, such as dementia, schizophrenia and acute hallucinatory episodes, depression, anxiety, Parkinson's disease, cardiovascular conditions and urinary incontinence.

Orthopedic Surgery Triggers Attention Deficits in a Delirium-Like Mouse Model

Postoperative delirium is a frequent and debilitating complication, especially amongst high risk procedures such as orthopedic surgery, and its pathogenesis remains unclear. Inattention is often reported in the clinical diagnosis of delirium, however limited attempts have been made to study this cognitive domain in preclinical models. Here we implemented the 5-choice serial reaction time task (5-CSRTT) to evaluate attention in a clinically relevant mouse model following orthopedic surgery. The 5-CSRTT showed a time-dependent impairment in the number of responses made by the mice acutely after orthopedic surgery, with maximum impairment at 24 h and returning to pre-surgical performance by day 5. Similarly, the latency to the response was also delayed during this time period but returned to pre-surgical levels within several days. While correct responses decreased following surgery, the accuracy of the response (e.g., selection of the correct nose-poke) remained relatively unchanged. In a separate cohort we evaluated neuroinflammation and blood-brain barrier (BBB) dysfunction using clarified brain tissue with light-sheet microscopy. CLARITY revealed significant changes in microglial morphology and impaired astrocytic-tight junction interactions using high-resolution 3D reconstructions of the neurovascular unit. Deposition of IgG, fibrinogen, and autophagy markers (TFEB and LAMP1) were also altered in the hippocampus 24 h after surgery. Together, these results provide translational evidence for the role of peripheral surgery contributing to delirium-like behavior and disrupted neuroimmunity in adult mice.

Anticholinergic Medication Burden in Pediatric Prolonged Critical Illness: A Potentially Modifiable Risk Factor for Delirium

OBJECTIVES

It is important to describe and understand the prevalence and risk factors for the syndrome of delirium in critical illness. Since anticholinergic medication may contribute to the development of delirium in the PICU, we have sought to quantify anticholinergic medication exposure in patients with prolonged admission. We have used Anticholinergic Drug Scale scores to quantify the magnitude or extent of this burden.

DESIGN

Retrospective cohort study, January 2011 to December 2015.

SETTING

Single academic medical center PICU.

PATIENTS

Children under 18 years old with a PICU admission of 15 days or longer, requiring mechanical ventilation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Daily Anticholinergic Drug Scale scores for the first 15 days of admission, in each of 88 subjects (total of 1,320 PICU days), were collected and assessed in relation to demographic data, severity of illness, and medication use. Median (interquartile range) of daily Anticholinergic Drug Scale score was 5 (interquartile range, 3-7). Anticholinergic Drug Scale score was not associated with age, sex, medical history, presenting Severity of Illness score, PICU length of stay, ventilator hours, or hospital mortality. Medications most frequently associated with high Anticholinergic Drug Scale score were low potency anticholinergic drugs such as morphine, midazolam, vancomycin, steroids, and furosemide, with the exception of ranitidine (Anticholinergic Drug Scale score 2). Patients receiving high doses of midazolam infusion had significantly higher Anticholinergic Drug Scale scores compared with those receiving lower or no midazolam dosing.

CONCLUSIONS

A high number of medications with anticholinergic effects are administered to PICU patients receiving prolonged mechanical ventilation. These exposures are much higher than those reported in adult intensive care patients. Since anticholinergic drug exposure is associated with delirium, further study of this exposure in PICU patients is needed.

Delirium and exposure to psychoactive medications in critically ill adults: A multi-centre observational study

PURPOSE

Investigate the relationship between psychoactive drugs and delirium.

MATERIALS AND METHODS

Prospective observational study of 520 critically ill adult patients admitted ≥24h to 6 intensive care units (ICUs). Data were collected on psychoactive drug exposure, use of sedation administration strategies, and incident delirium (Intensive Care Delirium Screening Checklist score≥4).

RESULTS

Delirium was detected in 260 (50%) patients, median (IQR) duration 2 (1-5) days, and time to onset 3 (2-5) days. Delirious patients received more low-potency anticholinergic (P<0.0001), antipsychotic (P<0.0001), benzodiazepine (P<0.0001) and non-benzodiazepine sedative (P<0.0001), and opioid (P=0.0008) drugs. Primary regression (24-hours preceding drug exposure) revealed no association between any psychoactive drug and delirium. Post-hoc analysis (extended 48-hour exposure) revealed an association between delirium and high-potency anticholinergic (HR 2.45, 95% CI 1.08-5.54) and benzodiazepine (HR 1.08 per 5mg midazolam-equivalent increment, 95% CI 1.04-1.12) drugs. Delirious patients had longer ICU (P<0.0001) and hospital (P<0.0001) length of stay, and higher ICU and hospital mortality (P=0.003 and P=0.007, respectively).

CONCLUSIONS

The identification of psychoactive drugs as modifiable delirium risk factors plays an important role in the management of critically ill patients. This is particularly important given the burden of exposure and combinations of drugs used in this vulnerable patient population.

Anticholinergic drug exposure is associated with delirium and postdischarge institutionalization in acutely ill hospitalized older patients

Several studies investigated the possible association between anticholinergic drugs and diverse clinical outcomes in older persons, but the results are inconsistent. The aim of this study was to investigate whether anticholinergic drug exposure is associated with delirium on admission, length of hospital stay, postdischarge institutionalization and in-hospital mortality in acutely ill hospitalized older patients. In this observational chart review study, we included acutely ill patients aged 65 and older who were admitted to the geriatric ward of the Erasmus University Medical Center, Rotterdam, The Netherlands, between 2012 and 2015 (n = 905). Anticholinergic drug exposure on admission was defined as the use of anticholinergic drugs, total number of anticholinergic drugs and anticholinergic drug burden score (ADB), quantified with the Anticholinergic Risk Scale (ARS), the Anticholinergic Cognitive Burden scale (ACB) and the list of Chew et al. (Chew). Logistic regression analyses were performed to investigate possible associations between anticholinergic drug exposure and the aforementioned outcomes. Analyses were adjusted for age, sex, comorbidities, non-anticholinergic drugs and delirium, where appropriate. Moderate and high ADB measured with the ARS were associated with delirium on admission with odds ratios (OR) of 1.70 (95% confidence interval (CI) = 1.16-2.49) and 1.83 (95% CI = 1.06-3.15), respectively. High ADB measured with the ARS was also associated with postdischarge institutionalization (OR = 2.43, 95% CI = 1.24-4.75). No associations were found using the ACB and Chew. Future studies are warranted to investigate the clinical usefulness of the ARS in reducing complications in older persons.

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.

Polypharmacy and Delirium in Critically Ill Older Adults: Recognition and Prevention

Among older adults, polypharmacy is a sequelae of admission to the intensive care unit and is associated with increased medication-associated adverse events, drug interactions, and health care costs. Delirium is prevalent in critically ill geriatric patients and medications remain an underappreciated modifiable risk for delirium in this setting. This article reviews the literature on polypharmacy and delirium, with a focus on highlighting the relationships between polypharmacy and delirium in critically ill, older adults. Discussed are clinician strategies on how to recognize and reduce medication-associated delirium and recommendations that help prevent polypharmacy when interventions to reduce the burden of delirium in this vulnerable population are being formulated.

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.

Systemic Corticosteroids and Transition to Delirium in Critically Ill Patients

OBJECTIVE

Corticosteroids are frequently used in critically ill patients. We investigated whether systemic corticosteroid use increases the probability of transitioning to delirium in a large population of mixed medical-surgical ICU patients.

DESIGN

Prospective cohort study.

SETTING

A 32-bed medical-surgical ICU at an academic medical center.

PATIENTS

Critically ill adults (n = 1,112), admitted to the ICU for more than 24 hours without a condition that could hamper delirium assessment.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Systemic corticosteroid exposure was measured daily and converted to prednisone equivalents (milligrams). Daily mental status was classified as coma, delirium, or an awake without delirium state. Transitions between states were analyzed using a first-order Markov multinomial logistic regression model with 11 different covariables, with the transition from an awake without delirium state to delirium as a primary interest. Among the 1,112 patients, corticosteroids were administered on 35% (3,483/9,867) of the ICU days at a median dose of 50 mg (interquartile range, 25-75 mg) prednisone equivalent. Administration of a corticosteroid, and any increase in the dose of the corticosteroid given on exposure days, was not significantly associated with the transition to delirium (adjusted odds ratio, 1.08; 95% CI, 0.89-1.32 and adjusted odds ratio, 1.00; 95% CI, 0.99-1.01, per 10 mg increase in prednisone equivalent).

CONCLUSIONS

In a large population of mixed medical-surgical ICU patients, systemic corticosteroid use was not associated with an increased probability of transitioning to delirium.