Original Study
Ultra-brief Screeners for Detecting Delirium Superimposed on Dementia

https://doi.org/10.1016/j.jamda.2019.05.011Get rights and content

Abstract

Objective

Delirium superimposed on dementia (DSD) is common, morbid, and costly, yet frequently undiagnosed. Our study aimed to develop a brief screening test to improve health care worker recognition of DSD.

Design/Setting/Participants

Older hospitalized adults with dementia were prospectively enrolled from medical and surgical inpatient units of 3 hospitals (2 in Pennsylvania, 1 in Tennessee).

Measures

The reference standard delirium assessment used Confusion Assessment Method (CAM) criteria and was based on a structured interview including the Mini-Mental State Examination, interviewer observations, and medical record review. To develop the screening test, 1-, 2-, and 3-item combinations from the reference standard assessment were analyzed to determine their sensitivity and specificity in diagnosing delirium presence in a dementia population compared to the reference standard. For multiple-item screeners, error on 1 or more items was considered a positive screen.

Results

Overall, 391 older adults with dementia were enrolled (mean age: 83.9 years, 71.1% female), and 95 (24.4%) developed DSD during their hospitalization, based on the reference standard. The best single-item screen for DSD was “What day of the week is it?” with 84% sensitivity [95% confidence interval (CI): 0.75, 0.91] and 41% specificity (CI: 0.35, 0.47). The best 2-item screen was “list the days of the week backwards” and “What day of the week is it?” with 93% sensitivity (CI: 0.85, 0.97) and 30% specificity (CI: 0.25, 0.36). The best 3-item screen was “list the days of the week backwards,” “What type of place is this? [hospital]” and “Does the patient appear sleepy?” with 94% sensitivity (CI: 0.87, 0.98) and 42% specificity (CI: 0.36, 0.48).

Conclusions/Implications

We identified a 3-item DSD screener with excellent sensitivity but limited specificity. This screener can be used to quickly rule out DSD in populations with a high prevalence of dementia and is a promising step toward developing efficient tools for DSD recognition among care providers.

Section snippets

Study Sample and Design

We performed secondary data analysis of a prospective cluster randomized trial, Early Nurse Detection of Delirium Superimposed on Dementia (END-DSD), conducted between 2010 and 2014 across 3 acute care settings, 2 in Pennsylvania and 1 in Tennessee, as described elsewhere.19 Inclusion criteria for study participation included (1) prior history of dementia, (2) age 65 years or greater, (3) admission to a general medicine or surgery unit, and (4) enrollment within 24 hours of hospitalization.

Patient Characteristics

Three hundred ninety-one patients met the inclusion criteria and were enrolled. The mean age was 83.9 (SD = 6.1); 278 (71.1%) were female and 371 (94.9%) were white. Mild, moderate, and advanced dementia was present in 198 (50.6%), 134 (34.3%), and 59 (15.1%) of the patients, respectively. Ninety-two (23.5%) of the participants had less than a high school education, 179 (45.8%) completed high school, and 120 (30.7%) attended college and beyond. Depression was present in 101 (25.8%). Finally, 95

Discussion

Delirium is a common occurrence in people with underlying dementia, including nursing home residents experiencing an acute illness, and those recently hospitalized.28, 29 Despite this, DSD is frequently under-recognized by health care clinicians.1, 30 This study demonstrates that a brief 3-item screening test containing the items “days of the week backwards,” “What type of place is this,” and “Is the patient sleepy?” can detect more than 90% of DSD, while also effectively ruling out more than

Conclusion and Implications

In conclusion, we identified a 3-item screener that can effectively detect DSD. Once validated, this screener could assist clinicians in environments with a high prevalence of dementia to rapidly exclude patients without delirium and identify those who require further testing. Ultimately, our screener will facilitate the challenging process of identifying delirium in persons with dementia, with the potential to improve patient outcomes and decrease costs in this population of older adults.

Acknowledgments

We thank the older adult participants, unit champions, and staff members at the study hospitals, without whom the study would not have been possible. We also thank the research assistants and staff and dedicate this article in memory of Jane McDowell, the project director for END-DSD and a nurse champion of improving the care of older adults.

References (35)

  • S.K. Inouye et al.

    Nurses' recognition of delirium and its symptoms: Comparison of nurse and researcher ratings

    Arch Intern Med

    (2001)
  • T.A. Jackson et al.

    Challenges and opportunities in understanding dementia and delirium in the acute hospital

    PLoS Med

    (2017)
  • A. Morandi et al.

    Tools to detect delirium superimposed on dementia: A systematic review

    J Am Geriatr Soc

    (2012)
  • M.R. Steis et al.

    Licensed nurse and nursing assistant recognition of delirium in nursing home residents with dementia

    Ann Longterm Care

    (2015)
  • S.K. Inouye et al.

    Clarifying confusion: The confusion assessment method. A new method for detection of delirium

    Ann Intern Med

    (1990)
  • E.L. van Velthuijsen et al.

    Psychometric properties and feasibility of instruments for the detection of delirium in older hospitalized patients: A systematic review

    Int J Geriatr Psychiatry

    (2016)
  • E.R. Marcantonio et al.

    3D-CAM: Derivation and validation of a 3-minute diagnostic interview for CAM-defined delirium: A cross-sectional diagnostic test study

    Ann Intern Med

    (2014)
  • Cited by (12)

    • The 4-DSD: A New Tool to Assess Delirium Superimposed on Moderate to Severe Dementia

      2021, Journal of the American Medical Directors Association
      Citation Excerpt :

      Future multicenter studies are necessary to further investigate this new tool to include a larger group of patients with severe dementia and to analyze if it could be created as a 2-step approach with one 4-DSD item considered as a screening step and then perform the full 4-DSD if the screening is positive. Recently, Steensma and colleagues39 proposed a screening test for DSD with 1-, 2-, and 3-item combinations, including various questions to be answered by the patient. They specifically looked at the performance of this approach in different stages of dementia, so one could use the 3-item combination screening and then perform the full 4-DSD evaluation.

    • Delirium Assessment in Critically Ill Older Adults: Considerations During the COVID-19 Pandemic

      2021, Critical Care Clinics
      Citation Excerpt :

      The CAM-ICU has an option to use a visual attention form to assess feature 2, the core feature of delirium, which can be useful in identifying delirium in patients with dementia. Other screening tools validated in larger populations of patients with dementia (the 4As test,49 6-Item Cognitive Impairment Test,50 3-Item Screener51) require patients to be verbal, which is often a barrier to implementation in the ICU. Hearing impairment can result in inappropriate answers to questions if an older adult does not correctly interpret the information communicated by the health care provider.

    • Delirium Superimposed Upon Dementia

      2019, Journal of the American Medical Directors Association
    • Delirium superimposed on dementia: Early detection and treatment

      2023, Zeitschrift fur Gerontologie und Geriatrie
    • Delirium in older patients

      2022, Pathy's Principles and Practice of Geriatric Medicine
    View all citing articles on Scopus

    Funding sources: NIA and NINR Grants T35AG038027, R01AG030618, R01NR011042, and K24AG035075.

    E.R. Marcantonio and D. Fick served in equal roles as senior investigators in this study.

    The authors declare no conflicts of interest.

    View full text