Outcomes in complex patients with delirium and subsyndromal delirium one year after hospital discharge

Prevalence and risk factors of subsyndromal delirium among postoperative patients: A systematic review and meta-analysis

AIM

The aim of this study is to determine the prevalence and risk factors for subsyndromal delirium in the postoperative patient.

DESIGN

A systematic review and meta-analysis.

METHODS

The Review Manager 5.3 statistics platform and the Newcastle-Ottawa Scale were used for quality evaluation.

DATA SOURCES

The following databases were searched: PubMed, Web of Science, EMBASE, The Cochrane Library, Scopus and EBSCO from January 2000 to December 2021. Additional sources were found by looking at relevant articles' citations.

RESULTS

A total of 1744 titles were originally identified, and five studies including 962 patients were included in the systematic review, with a pooled prevalence of postoperative subsyndromal delirium (PSSD) of 30% (95% CI: 0.28-0.32). Significant risk variables for PSSD were older age, low levels of education (≤9 years), cognitive impairment, higher comorbidity score, and the duration of operation.

CONCLUSION

PSSD is prevalent and is associated with a variety of risk factors as well as low academic performance.

IMPACT

Identification and clinical management of patients with PSSD should be improved. Future research on PSSD risk factors should look at a wider range of intraoperative and postoperative risk factors that can be changed.

PATIENT AND PUBLIC CONTRIBUTION

No Patient or Public Contribution.

The risk factors for and the frequency and outcomes of subsyndromal delirium among patients who have undergone cardiac surgery: a protocol for systematic review and meta-analysis

INTRODUCTION

Several key symptoms must be present for the accurate diagnosis of patients with postoperative cardiac delirium. Some patients present with symptoms of delirium but do not meet the diagnostic criteria for delirium; such individuals are considered to have having subsyndromal delirium (SSD). SSD is associated with misdiagnosis and poor outcomes. However, to date, no systematic review (SR) has examined the frequency of, risk factors for, and outcomes of SSD among adults who have undergone cardiac surgery.

METHODS AND ANALYSIS

The aim of this SR is to identify those studies that have explored SSD after cardiac surgery. MeSH and free entry terms associated with "subsyndromal delirium" and "subclinical delirium" will be used to search for relevant studies. The PubMed, Web of Science, OVID, Cochrane Library, CINAHL, EMBASE, PsycINFO, China National Knowledge Infrastructure, Wanfang data, VIP database and SinoMed will be searched from inception to the date of retrieval without any restrictions. The primary outcomes will be the frequency of SSD, the risk factors for SSD, and the outcomes of SSD. Analyses will be performed using STATA V.16.0, and descriptive analyses will be performed if the data are not suitable for meta-analysis (ie, data with significant heterogeneity or from different comparisons).

ETHICS AND DISSEMINATION

The SR will examine the frequency of, risk factors for and outcomes of SSD in adults who have undergone cardiac surgery. The results will provide guidance for the identification of knowledge gaps in this field, and areas for further research will be highlighted. The review protocol will be submitted for publication in peer-reviewed journals for dissemination of the findings. Individual patient data will not be included in this protocol, so ethical approval will not be needed.

PROSPERO REGISTRATION NUMBER

CRD42022379211.

Frequency and Risk Factors of Subsyndromal Delirium in the Intensive Care Units: A Prospective Cohort Study

Background

Subsyndromal delirium (SSD) is a common neuropsychiatric disorder among the intensive care units (ICU) patients. SSD is characterized by the presence of delirium symptoms but it does not meet the diagnostic criteria of delirium, resulting in poor patient prognosis.

Objective

The aim of this study was to explore the prevalence and risk factors for SSD among adult patients admitted to the ICU of XXX hospital in Southwest China.

Methods

The study participants comprised 309 patients referred to the ICU in XXX hospital between 10th August 2021 and 5th June 2022. Demographic information, medical history, and other patient information were recorded. ICDSC assessment, physical examination and laboratory tests were performed on enrolled patients. Cognitive evaluation was conducted using the MMSE method.

Results

The results showed that out the 309 patients, 99 had possible SSD (prevalence of 32.0%), with 55 SSD1 cases (ICDSC score of 1, 17.8% prevalence), 29 SSD2 cases (ICDSC score of 2, 9.4% prevalence) and 15 SSD3 cases (ICDSC score of 3, 4.9% prevalence). Previous history of mental illness (OR, 3.741; 95% CI, 1.136-12.324; P <0.05), auxiliary ventilation (OR, 3.364; 95% CI, 1.448-7.813; P <0.01), hemodialysis (OR, 11.369; 95% CI, 1.245-103.840; P <0.05), MMSE score (OR, 0.845; 95% CI, 0.789-0.904; P <0.001) and a temperature ≥ 37.5 °C (OR, 3.686; 95% CI, 1.404-9.732; P <0.01) were independent risk factors for occurrence of SSD among ICU patients.

Conclusion

Approximately one-third of the patients in the intensive care unit had high risk of SSD. Nursing staff should pay attention to management of the high-risk patients to prevent SSD from progressing delirium to improve patient prognosis.

Understanding health-care outcomes of older people with cognitive impairment and/or dementia admitted to hospital: a mixed-methods study

Background

Cognitive impairment is common in older people admitted to hospital, but previous research has focused on single conditions.

Objective

This project sits in phase 0/1 of the Medical Research Council Framework for the Development and Evaluation of Complex Interventions. It aims to develop an understanding of current health-care outcomes. This will be used in the future development of a multidomain intervention for people with confusion (dementia and cognitive impairment) in general hospitals. The research was conducted from January 2015 to June 2018 and used data from people admitted between 2012 and 2013.

Design

For the review of outcomes, the systematic review identified peer-reviewed quantitative epidemiology measuring prevalence and associations with outcomes. Screening for duplication and relevance was followed by full-text review, quality assessment and a narrative review (141 papers). A survey sought opinion on the key outcomes for people with dementia and/or confusion and their carers in the acute hospital (n = 78). For the analysis of outcomes including cost, the prospective cohort study was in a medical admissions unit in an acute hospital in one Scottish health board covering 10% of the Scottish population. The participants (n = 6724) were older people (aged ≥ 65 years) with or without a cognitive spectrum disorder who were admitted as medical emergencies between January 2012 and December 2013 and who underwent a structured nurse assessment. ‘Cognitive spectrum disorder’ was defined as any combination of delirium, known dementia or an Abbreviated Mental Test score of < 8 out of 10 points. The main outcome measures were living at home 30 days after discharge, mortality within 2 years of admission, length of stay, re-admission within 2 years of admission and cost.

Data sources

Scottish Morbidity Records 01 was linked to the Older Persons Routine Acute Assessment data set.

Results

In the systematic review, methodological heterogeneity, especially concerning diagnostic criteria, means that there is significant overlap in conditions of patients presenting to general hospitals with confusion. Patients and their families expect that patients are discharged in the same or a better condition than they were in on admission or, failing that, that they have a satisfactory experience of their admission. Cognitive spectrum disorders were present in more than one-third of patients aged ≥ 65 years, and in over half of those aged ≥ 85 years. Outcomes were worse in those patients with cognitive spectrum disorders than in those without: length of stay 25.0 vs. 11.8 days, 30-day mortality 13.6% vs. 9.0%, 1-year mortality 40.0% vs. 26.0%, 1-year mortality or re-admission 62.4% vs. 51.5%, respectively (all p < 0.01). There was relatively little difference by cognitive spectrum disorder type; for example, the presence of any cognitive spectrum disorder was associated with an increased mortality over the entire period of follow-up, but with different temporal patterns depending on the type of cognitive spectrum disorder. The cost of admission was higher for those with cognitive spectrum disorders, but the average daily cost was lower.

Limitations

A lack of diagnosis and/or standardisation of diagnosis for dementia and/or delirium was a limitation for the systematic review, the quantitative study and the economic study. The economic study was limited to in-hospital costs as data for social or informal care costs were unavailable. The survey was conducted online, limiting its reach to older carers and those people with cognitive spectrum disorders.

Conclusions

Cognitive spectrum disorders are common in older inpatients and are associated with considerably worse health-care outcomes, with significant overlap between individual cognitive spectrum disorders. This suggests the need for health-care systems to systematically identify and develop care pathways for older people with cognitive spectrum disorders, and avoid focusing on only condition-specific pathways.

Future work

Development and evaluation of a multidomain intervention for the management of patients with cognitive spectrum disorders in hospital.

Study registration

This study is registered as PROSPERO CRD42015024492.

Funding

This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 9, No. 8. See the NIHR Journals Library website for further project information.

Incidence and risk factors of subsyndromal delirium after curative resection of gastric cancer

Background

Subsyndromal delirium, a condition in which patients exhibit some, but not all, of the symptoms of delirium, can negatively affect the outcomes of patients with cancer. However, the incidence of subsyndromal delirium in patients with gastric cancer is unknown. Here, we investigated the incidence and risk factors of subsyndromal delirium after curative resection of gastric cancer.

Methods

We recruited consecutive patients with gastric cancer who were scheduled for curative resection at a tertiary hospital. Patients’ subsyndromal delirium symptoms were serially assessed preoperatively and 1, 2, 3, and 7 days postoperatively using the Delirium Rating Scale-Revised-98 (DRS-R-98). A DRS-R-98 score of 8–14 at any postoperative assessment was considered to indicate subsyndromal delirium. Sociodemographic and pre−/intra-operative clinical data were also assessed. Logistic regression analyses were used to determine the associated risk factors.

Results

Data were analysed from 163 out of 217 eligible patients. Postoperative delirium occurred in one patient (0.6%) and subsyndromal delirium occurred in 19 patients (11.7%). Age ≥ 70 years (odds ratio, [OR] 3.85; 95% confidence interval [CI], 1.36–10.92; p = 0.011) and education level ≤ 9 years (OR, 3.98; 95% CI, 1.39–11.41; p = 0.010) were independent risk factors of subsyndromal delirium after adjusting for preoperative cognitive function. Other pre−/intra-operative variables including anxiety/depression, poor sleep quality, and anaesthesia duration were not associated with subsyndromal delirium.

Conclusions

In contrast to the low incidence of delirium among patients undergoing curative resection of gastric cancer, a substantial proportion of such patients experienced subsyndromal delirium. Considering the prognostic implications, more careful detection and management of subsyndromal delirium may be warranted in patients with gastric cancer.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4681-2) contains supplementary material, which is available to authorized users.

A comparison of delirium diagnosis in elderly medical inpatients using the CAM, DRS-R98, DSM-IV and DSM-5 criteria

BACKGROUND

The recently published DSM-5 criteria for delirium may lead to different case identification and rates of delirium than previous classifications. The aims of this study are to determine how the new DSM-5 criteria compare with DSM-IV in identification of delirium in elderly medical inpatients and to investigate the agreement between different methods, using CAM, DRS-R98, DSM-IV, and DSM-5 criteria.

METHODS

Prospective, observational study of elderly patients aged 70+ admitted under the acute medical teams in a regional general hospital. Each participant was assessed within 3 days of admission using the DSM-5, and DSM-IV criteria plus the DRS-R98, and CAM scales.

RESULTS

We assessed 200 patients [mean age 81.1±6.5; 50% female; pre-existing cognitive impairment in 63%]. The prevalence rates of delirium for each diagnostic method were: 13.0% (n = 26) for DSM-5; 19.5% (n = 39) for DSM-IV; 13.5% (n = 27) for DRS-R98 and 17.0%, (n = 34) for CAM. Using tetrachoric correlation coefficients the agreement between DSM-5 and DSM-IV was statistically significant (ρtetr = 0.64, SE = 0.1, p < 0.0001). Similar significant agreement was found between the four methods.

CONCLUSIONS

DSM-IV is the most inclusive diagnostic method for delirium, while DSM-5 is the most restrictive. In addition, these classification systems identify different cases of delirium. This could have clinical, financial, and research implications. However, both classification systems have significant agreement in the identification of the same concept (delirium). Clarity of diagnosis is required for classification but also further research considering the relevance in predicting outcomes can allow for more detailed evaluation of the DSM-5 criteria.

Frequency of delirium and subsyndromal delirium in an adult acute hospital population

Background The frequency of full syndromal and subsyndromal delirium is understudied. Aims We conducted a point prevalence study in a general hospital. Method Possible delirium identified by testing for inattention was evaluated regarding delirium status (full/subsyndromal delirium) using categorical (Confusion Assessment Method (CAM), DSM-IV) and dimensional (Delirium Rating Scale-Revised-98 (DRS-R98) scores) methods. Results In total 162 of 311 patients (52%) screened positive for inattention. Delirium was diagnosed in 55 patients (17.7%) using DSM-IV, 52 (16.7%) using CAM and 58 (18.6%) using DRS-R98⩾12 with concordance for 38 (12.2%) individuals. Subsyndromal delirium was identified in 24 patients (7.7%) using a DRS-R98 score of 7-11 and 41 (13.2%) using 2/4 CAM criteria. Subsyndromal delirium with inattention (v. without) had greater disturbance of multiple delirium symptoms. Conclusions The point prevalence of delirium and subsyndromal delirium was 25%. There was modest concordance between DRS-R98, DSM-IV and CAM delirium diagnoses. Inattention should be central to subsyndromal delirium definitions.

Delirium diagnostic and classification challenges in palliative care: subsyndromal delirium, comorbid delirium-dementia, and psychomotor subtypes

CONTEXT

Delirium often presents difficult diagnostic and classification challenges in palliative care settings.

OBJECTIVES

To review three major areas that create diagnostic and classification challenges in relation to delirium in palliative care: subsyndromal delirium (SSD), delirium in the context of comorbid dementia, and classification of psychomotor subtypes, and to identify knowledge gaps and research priorities in relation to these three areas of focus.

METHODS

We combined multidisciplinary input from delirium researchers and knowledge users at an international delirium study planning meeting and relevant PubMed literature searches as the knowledge synthesis strategy in this review.

RESULTS

We identified six (SSD), 33 (dementia), and 44 (psychomotor subtypes) articles of relevance in relation to the focus of our review. Recent literature data highlight the frequency and impact of SSD, the relevance of comorbid dementia, and the propensity for a hypoactive presentation of delirium in the palliative population. The differential diagnoses to consider are wide and include pain, fatigue, mood disturbance, psychoactive medication effects, and other causes for altered consciousness.

CONCLUSION

Challenges in the diagnosis and classification of delirium in people with advanced disease are compounded by the generalized disturbance of central nervous system function that occurs in the seriously ill, often with comorbid illness, including dementia. Further research is needed to delineate the pathophysiological and clinical associations of these presentations and thus inform therapeutic strategies. The expanding aged population and growing focus on dementia care in palliative care highlight the need to conduct this research.