Diagnosis of delirium and confusional states
- Joseph Francis, Jr, MD, MPH
Joseph Francis, Jr, MD, MPH
- Deputy Chief Improvement and Analytics Officer
- Veterans Health Administration, Washington, DC
- G Bryan Young, MD, FRCPC
G Bryan Young, MD, FRCPC
- Professor of Neurology
- University of Western Ontario, Canada
- Section Editors
- Michael J Aminoff, MD, DSc
Michael J Aminoff, MD, DSc
- Editor-in-Chief — Neurology
- Section Editor — Medical Neurology
- Professor of Neurology
- University of California, San Francisco School of Medicine
- Kenneth E Schmader, MD
Kenneth E Schmader, MD
- Editor in Chief — Geriatric Medicine
- Section Editor — Geriatrics
- Chief, Division of Geriatrics
- Duke University
- Director, Geriatric Research Education and Clinical Center
- Durham VA Medical Centers
Delirium and confusional states are among the most common mental disorders encountered in patients with medical illness, particularly among those who are older. They are associated with many complex underlying medical conditions and can be hard to recognize. Systematic studies and clinical trials are difficult to perform in patients with cognitive impairment. Recommendations for evaluating and treating delirium are based primarily upon clinical observation and expert opinion .
Knowledge of the clinical epidemiology of delirium and confusional states in various settings has substantially increased as a result of applying standardized diagnostic methods. These prospective observational studies provide a basis for understanding and managing the disorder.
The epidemiology, pathogenesis, clinical features, and diagnosis of delirium and confusional states will be reviewed here. The prevention and treatment of these disorders are discussed separately. (See "Delirium and acute confusional states: Prevention, treatment, and prognosis".)
DEFINITION AND TERMINOLOGY
The American Psychiatric Association's Diagnostic and Statistical Manual, 5th edition (DSM-V) lists five key features that characterize delirium :
●Disturbance in attention (reduced ability to direct, focus, sustain, and shift attention) and awareness.
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- DEFINITION AND TERMINOLOGY
- Neurobiology of attention
- Cortical versus subcortical mechanisms
- Neurotransmitter and humoral mechanisms
- Risk factors
- Precipitating factors
- CLINICAL PRESENTATION
- Disturbance of consciousness
- Change in cognition
- Temporal course
- Elderly patients
- Other features
- Recognizing the disorder
- Clinical confirmation
- - History
- - General examination
- - Neurologic examination
- - Clinical instruments
- Investigating medical etiologies
- Medication review
- DIFFERENTIAL DIAGNOSIS
- Focal syndromes
- Nonconvulsive status epilepticus
- Primary psychiatric illnesses
- DIAGNOSTIC TESTS
- Laboratory tests
- Lumbar puncture
- EEG testing
- INFORMATION FOR PATIENTS
- SUMMARY AND RECOMMENDATIONS