Association between frailty, delirium, and mortality in older critically ill patients: a binational registry study

Implications of frailty before and after intensive care unit admission

PURPOSE OF REVIEW

In the decade since the first publications related to frailty in those with critical illness, the study of frailty has rapidly increased. The purpose of this review is to update the reader on recent advances across several important areas of frailty research: how best to identify frailty in those with critical illness, studies describing the relationship between frailty and delirium, and how frailty affects outcomes for those with coronavirus disease 2019 (COVID-19), which, despite rates and severity of acute infection declining, still tremendously impacts patients long after the acute infection, resulting in symptoms of long COVID-19.

RECENT FINDINGS

A number of frailty assessment tools exist, to date, the Clinical Frailty Scale based on the deficit accumulation approach to defining frailty, is the most commonly used in ICU studies. Several novel frailty instruments for the ICU are being developed. Because tools assessing frailty by the phenotypic and deficit accumulation approaches identify different populations, careful choice of a frailty assessment tool is warranted.Frailty and delirium are hypothesized to represent different clinical expressions of a similar underlying vulnerability, thus identifying frailty may be a useful means by which to identify patients at high risk of becoming delirious. Recent studies show that frailty at ICU admission is a predictor of the development of delirium.Finally, frailty and its outcomes were studied in patients with COVID-19. As with other causes of critical illness, frailty was highly prevalent in those admitted to the ICU and is associated with greater mortality. Frailty was also associated with increased decisions to limit life support treatments, but these decisions were not different among those admitted with COVID-19 or for other reasons.

SUMMARY

Frailty in those with critical illness is an emerging field of study. Future work to define the optimal means by which to identify this syndrome and how best to manage critically ill patients with frailty are needed.

Association of Delirium with Long-Term Mortality in Critically Ill Patients with COPD Who Survived to Discharge: A Retrospective Cohort Study

BACKGROUND

Critically ill patients with chronic obstructive pulmonary disease (COPD) face significant mortality after hospital discharge. Delirium is common in patients with COPD, but its impact on long-term mortality in critically ill COPD patients who survive to discharge remains uncertain.

METHODS

Critically ill patients with COPD who survived to discharge were selected from the Medical Information Mart for Intensive Care IV database. Delirium was assessed using the Confusion Assessment Method for Intensive Care Unit. The primary outcome was 365- and 180-day mortality after discharge. The secondary outcomes included 90- and 30-day mortality following discharge, length of intensive care unit (ICU) and hospital stays, and nursing care needs after hospital discharge.

RESULTS

Of the 2621 survivors of critically ill COPD patients, 982 had suffered delirium during their ICU stay and 709 died within 365 days after hospital discharge. Delirium was significantly associated with 365-day mortality after hospital discharge (adjusted hazard ratio [HR] 1.22; 95% confidence interval [CI] 1.02-1.47). The results were consistent for 180-, 90-, and 30-day post-discharge mortality (adjusted HR [95% CI]: 1.35 [1.09-1.66], 1.48 [1.16-1.89], and 1.68 [1.21-2.32], respectively). Additionally, patients with delirium had longer ICU and hospital stay (adjusted β 2.75; 95% CI 2.35-3.16 and 4.25; 95% CI 3.51-4.98, respectively) and increased nursing care needs after hospital discharge (adjusted odds ratio, 1.56; 95% CI 1.13-2.14).

CONCLUSION

ICU delirium was an independent risk factor for both long-term and short-term mortality in critically ill patients with COPD who survived to discharge.

Can admission Braden skin score predict delirium in older adults in the intensive care unit? Results from a multicenter study

AIMS AND OBJECTIVES

To investigate whether a low Braden Skin Score (BSS), reflecting an increased risk of pressure injury, could predict the risk of delirium in older patients in the intensive care unit (ICU).

BACKGROUND

Delirium, a common acute encephalopathy syndrome in older ICU patients, is associated with prolonged hospital stay, long-term cognitive impairment and increased mortality. However, few studies have explored the relationship between BSS and delirium.

DESIGN

Multicenter cohort study.

METHODS

The study included 24,123 older adults from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database and 1090 older adults from the eICU Collaborative Research Database (eICU-CRD), all of whom had a record of BSS on admission to the ICU. We used structured query language to extract relevant data from the electronic health records. Delirium, the primary outcome, was primarily diagnosed by the Confusion Assessment Method for the ICU or the Intensive Care Delirium Screening Checklist. Logistic regression models were used to validate the association between BSS and outcome. A STROBE checklist was the reporting guide for this study.

RESULTS

The median age within the MIMIC-IV and eICU-CRD databases was approximately 77 and 75 years, respectively, with 11,195 (46.4%) and 524 (48.1%) being female. The median BSS at enrollment in both databases was 15 (interquartile range: 13, 17). Multivariate logistic regression showed a negative association between BSS on ICU admission and the prevalence of delirium. Similar patterns were found in the eICU-CRD database.

CONCLUSIONS

This study found a significant negative relationship between ICU admission BSS and the prevalence of delirium in older patients.

RELEVANCE TO CLINICAL PRACTICE

The BSS, which is simple and accessible, may reflect the health and frailty of older patients. It is recommended that BSS assessment be included as an essential component of delirium management strategies for older patients in the ICU.

NO PATIENT OR PUBLIC CONTRIBUTION

This is a retrospective cohort study, and no patients or the public were involved in the design and conduct of the study.

Ethical issues surrounding appropriate care for older persons in the Intensive Care Unit

Increasing numbers of older patients are being admitted to the Intensive Care Unit (ICU) as the world's population ages. The biological process of ageing, senescence, results in altered ability to maintain normal homeostasis and organ function, including of the cardiovascular, immune, and neuromuscular systems. This contributes towards increased frailty in older patients, associated with functional limitations and increased vulnerability. Although widely defined using chronological age, the concept of "old age" is thus multifactorial, including biological, but also psychological and sociocultural aspects, which should all be taken into account when considering what is appropriate in terms of ICU admission and management. As for all patients, but perhaps particularly in this subgroup, decisions regarding ICU admission and treatment and the withdrawing and withholding of life support must be individualized.

National ICU Registries as Enablers of Clinical Research and Quality Improvement

OBJECTIVES

Clinical quality registries (CQRs) have been implemented worldwide by several medical specialties aiming to generate a better characterization of epidemiology, treatments, and outcomes of patients. National ICU registries were created almost 3 decades ago to improve the understanding of case-mix, resource use, and outcomes of critically ill patients. This narrative review describes the challenges, proposed solutions, and evidence generated by National ICU registries as facilitators for research and quality improvement.

DATA SOURCES

English language articles were identified in PubMed using phrases related to ICU registries, CQRs, outcomes, and case-mix.

STUDY SELECTION

Original research, review articles, letters, and commentaries, were considered.

DATA EXTRACTION

Data from relevant literature were identified, reviewed, and integrated into a concise narrative review.

DATA SYNTHESIS

CQRs have been implemented worldwide by several medical specialties aiming to generate a better characterization of epidemiology, treatments, and outcomes of patients. National ICU registries were created almost 3 decades ago to improve the understanding of case-mix, resource use, and outcomes of critically ill patients. The initial experience in European countries and in Oceania ensured that through locally generated data, ICUs could assess their performances by using risk-adjusted measures and compare their results through fair and validated benchmarking metrics with other ICUs contributing to the CQR. The accomplishment of these initiatives, coupled with the increasing adoption of information technology, resulted in a broad geographic expansion of CQRs as well as their use in quality improvement studies, clinical trials as well as international comparisons, and benchmarking for ICUs.

CONCLUSIONS

ICU registries have provided increased knowledge of case-mix and outcomes of ICU patients based on real-world data and contributed to improve care delivery through quality improvement initiatives and trials. Recent increases in adoption of new technologies (i.e., cloud-based structures, artificial intelligence, machine learning) will ensure a broader and better use of data for epidemiology, healthcare policies, quality improvement, and clinical trials.

Delirium During Critical Illness and Subsequent Change of Treatment in Patients With Cancer: A Mediation Analysis

OBJECTIVES

To assess whether delirium during ICU stay is associated with subsequent change in treatment of cancer after discharge.

DESIGN

Retrospective cohort study.

SETTING

A 50-bed ICU in a dedicated cancer center.

PATIENTS

Patients greater than or equal to 18 years old with a previous proposal of cancer treatment (chemotherapy, target therapy, hormone therapy, immunotherapy, radiotherapy, oncologic surgery, and bone marrow transplantation).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We considered delirium present if Confusion Assessment Method for the ICU was positive. We assessed the association between delirium and modification of the treatment after discharge. We also performed a mediation analysis to assess both the direct and indirect (i.e., mediated by the development of functional dependence after discharge) of delirium on modification of cancer treatment and whether the modification of cancer treatment was associated with mortality at 1 year. We included 1,134 patients, of whom, 189 (16.7%) had delirium. Delirium was associated with the change in cancer treatment (adjusted odds ratio [OR], 3.80; 95% CI, 2.72-5.35). The association between delirium in ICU and change of treatment was both direct and mediated by the development of functional dependence after discharge. The proportion of the total effect of delirium on change of treatment mediated by the development of functional dependence after discharge was 33.0% (95% CI, 21.7-46.0%). Change in treatment was associated with increased mortality at 1 year (adjusted OR, 2.68; 95% CI, 2.01-3.60).

CONCLUSIONS

Patients who had delirium during ICU stay had a higher rate of modification of cancer treatment after discharge. The effect of delirium on change in cancer treatment was only partially mediated by the development of functional dependence after discharge. Change in cancer treatment was associated with increased 1-year mortality.

Long-term mortality of critically ill patients with cancer and delirium who survived to discharge: a retrospective cohort study

PURPOSE

Delirium is common in critically ill patients and has been associated with lower short-term survival; however, its association with long-term survival has been scarcely evaluated and few studies have shown divergent results.

METHODS

We conducted a retrospective cohort study of adult patients with cancer admitted to the intensive care unit (ICU) and discharged from hospital from January 2015 to December 2018. We considered delirium present if the Confusion Assessment Method for Intensive Care Unit (CAM-ICU) result was positive. We assessed the association between delirium during ICU stay and long-term mortality (up to three years after discharge). We also assessed the association between delirium type (hypoactive, hyperactive, and mixed) with long-term mortality.

RESULTS

We included 3,079 patients. Of these, 430 (14%) were considered delirious at some point during their ICU stay. Delirium was associated with one-year mortality after hospital discharge (hazard ratio [HR], 1.58; 95% confidence interval [CI], 1.36 to 1.83) after adjustment for potential confounders, but not with one to three year-mortality (HR, 0.92; 95% CI, 0.61 to 1.39). Hypoactive and mixed delirium were associated with one-year mortality (HR, 1.77; 95% CI, 1.46 to 2.14 and HR, 1.56; 95% CI, 1.21 to 2.00, respectively), but none of the delirium motor types was associated with one to three-year mortality.

CONCLUSIONS

We observed that delirium during ICU stay was associated with increased one-year mortality, but was not with mortality after one year. This association was observed in hypoactive and mixed delirium types but not with hyperactive delirium.

Inclusion of frailty improved performance of delirium prediction for elderly patients in the cardiac intensive care unit (D-FRAIL): A prospective derivation and external validation study

BACKGROUND

The elderly patients admitted to cardiac intensive care unit (CICU) are at relatively high risk for developing delirium. A simple and reliable predictive model can benefit them from early recognition of delirium followed by timely and appropriate preventive strategies.

OBJECTIVE

To explore the role of frailty in delirium prediction and develop and validate a delirium predictive model including frailty for elderly patients in CICU.

DESIGN

A prospective, observational cohort study.

SETTINGS

CICU at China-Japan Friendship Hospital from March 1, 2022 to August 25, 2022 (derivation cohort); CICU at Beijing Anzhen Hospital affiliated to Capital Medical University from March 14, 2023 to May 8, 2023 (external validation cohort).

PARTICIPANTS

A total of 236 and 90 participants were enrolled in the derivation and external validation cohorts, respectively. Participants in the derivation cohort were assigned into either the delirium (n = 70) or non-delirium group (n = 166) based on the occurrence of delirium.

METHODS

The simplified Chinese version of the Confusion Assessment Method for the Diagnosis of Delirium in the Intensive Care Unit was used to assess delirium twice a day at 8:00-10:00 and 18:00-20:00 until the onset of delirium or discharge from the CICU. Frailty was assessed using the FRAIL scale during the first 24 h in the CICU. Other possible risk factors were collected prospectively through patient interviews and medical records review. After processing missing data via multiple imputations, univariate analysis and bootstrapped forward stepwise logistic regression were performed to select optimal predictors and develop the models. The models were internally validated using bootstrapping and evaluated comprehensively via discrimination, calibration, and clinical utility in both the derivation and external validation cohorts.

RESULTS

The study developed D-FRAIL predictive model using FRAIL score, hearing impairment, Acute Physiology and Chronic Health Evaluation-II score, and fibrinogen. The area under the receiver operating characteristic curve (AUC) was 0.937 (95% confidence interval [CI]: 0.907-0.967) and 0.889 (95%CI: 0.840-0.938) even after bootstrapping in the derivation cohort. Inclusion of frailty was demonstrated to improve the model performance greatly with the AUC increased from 0.851 to 0.937 (p < 0.001). In the external validation cohort, the AUC of D-FRAIL model was 0.866 (95%CI: 0.782-0.907). Calibration plots and decision curve analysis suggested good calibration and clinical utility of the D-FRAIL model in both the derivation and external validation cohorts.

CONCLUSIONS

For elderly patients in the CICU, FRAIL score is an independent delirium predictor and the D-FRAIL model demonstrates superior performance in predicting delirium.

Delirium and Its Association with Short- and Long-Term Health Outcomes in Medically Admitted Patients: A Prospective Study

BACKGROUND

Delirium is highly prevalent among elderly hospitalized patients in various healthcare settings. This study aimed to assess the impact of delirium on short- and long-term health outcomes.

METHODS

A prospective cohort included medically ill patients (≥65 years) admitted to a tertiary healthcare facility. Delirium was screened using the 3-Minute Diagnostic confusion assessment method (3D-CAM).

RESULTS

During hospitalization, 53.8% (n = 153/284) had delirium. Patients with delirium had a longer length of hospital stay (LOS) (7 vs. 5 days; p < 0.01) compared to patients without delirium. Delirium caused a higher frequency of high-dependency unit (HDU) or intensive care unit (ICU) admission (p < 0.01) and an increased incidence of hospital-acquired complications, including infections (p = 0.03), pressure injuries (p = 0.01), and upper gastrointestinal bleeding (p < 0.01). Inpatient all-cause mortality was higher in patients with delirium than those without delirium (16.3% vs. 1.5%; p < 0.01). Patients with delirium had higher rates of 90-day all-cause mortality (25.4% vs. 8.4%; p < 0.01) and 1-year all-cause mortality (35.9% vs. 16%; p < 0.01) compared to patients without delirium. Patients with delirium exhibited shorter survival periods at 90 days and 1 year compared to patients without delirium with a hazard ratio (HR) = 3.41, 95% CI: 1.75-6.66, p < 0.01 and HR = 2.64, 95% CI: 1.59-4.37, p < 0.01, respectively.

CONCLUSIONS

Delirium is associated with serious short-term and long-term clinical consequences. Early recognition, prevention, and targeted interventions addressing reversible risk factors are crucial. Further research is warranted to explore effective strategies for delirium management in general medical wards.