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Delirium and Its Motoric Subtypes: A Study of 614 Critically Ill Patients
Abstract
OBJECTIVES: To describe the motoric subtypes of delirium in critically ill patients and compare patients aged 65 and older with a younger cohort. DESIGN: Prospective cohort study. SETTING: The medical intensive care unit (MICU) of a tertiary care academic medical center. PARTICIPANTS: Six hundred fourteen MICU patients admitted during a process improvement initiative to monitor levels of sedation and delirium. MEASUREMENTS: MICU nursing staff assessed delirium and level of consciousness in all MICU patients at least once per 12-hour shift using the Confusion Assessment Method for the Intensive Care Unit and the Richmond Agitation-Sedation Scale. Delirium episodes were categorized as hypoactive, hyperactive, and mixed type. RESULTS: Delirium was detected in 112 of 156 (71.8%) subjects aged 65 and older and 263 of 458 (57.4%) subjects younger than 65. Mixed type was most common (54.9%), followed by hypoactive delirium (43.5%) and purely hyperactive delirium (1.6%). Patients aged 65 and older experienced hypoactive delirium at a greater rate than younger patients (41.0% vs 21.6%, P<.001) and never experienced hyperactive delirium. Older age was strongly and independently associated with hypoactive delirium (adjusted odds ratio=3.0, 95% confidence interval=1.7-5.3), compared with no delirium in a model that adjusted for other important determinants of delirium including severity of illness, sedative medication use, and ventilation status. CONCLUSION: Older age is a strong predictor of hypoactive delirium in MICU patients, and this motoric subtype of delirium may be missed in the absence of active monitoring.
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“Hyperactive delirium most often comes to clinical attention, but the mixed and hypoactive presentations are far more common [7,59,60,61].”
From Psychological and Psychiatric Comorbidities in Youth with Serious Physical Illness (2022) · cites this paper as [59]
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Metadata
- Authors
- Peterson, J. F., Pun, B. T., Dittus, R. S., Thomason, J. W. W., Jackson, J. C., Shintani, A. K., & Ely, E. W.
- Affiliations
- Vanderbilt University Medical Center (US)
- VA Tennessee Valley Healthcare System (US)
- Corresponding author
- Peterson, Josh F.
- Ely, E. Wesley
- Venue
- Journal of the American Geriatrics Society
- Publisher
- Wiley
- Published
- 2006-03
- Volume
- 54
- Issue
- 3
- Pages
- 479-484
- ISSN
- 0002-8614 (ISSN-L)
- 1532-5415
- OpenAlex
- W1505808688
- Cited by
- 660
- References
- 31
- Citations by year
- 2026: 11 · 2025: 17 · 2024: 32 · 2023: 37 · 2022: 21 · 2021: 33 · 2020: 32 · 2019: 45 · 2018: 44 · 2017: 41 · 2016: 48 · 2015: 37 · 2014: 29 · 2013: 42 · 2012: 44
- FWCI
- 27.31
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Journal of the American Geriatrics Society (publishedVersion)
- PubMed (publishedVersion)
- Funders
- Eli Lilly and Company
- Pfizer
- Topics
- Health Sciences › Medicine › Critical Care and Intensive Care Medicine › Intensive Care Unit Cognitive Disorders
- Health Sciences › Medicine › Anesthesiology and Pain Medicine › Anesthesia and Sedative Agents
- Health Sciences › Medicine › Clinical Neurology › Alcoholism and Thiamine Deficiency
- Keywords
- delirium, hypoactive delirium, hyperactive delirium, mixed delirium, critically ill patients, older adults, intensive care unit, age as predictor, sedation, level of consciousness, delirium monitoring
- MeSH terms
- Age Factors, Aged, Critical Care, Delirium, Female, Follow-Up Studies, Humans, Male, Motor Activity, Prognosis, Prospective Studies, Severity of Illness Index, Incidence, Prevalence, Critical Illness
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