Diagnosis of Dementia
Dementia is the decline of cognitive functioning - learning and memory, language, reasoning, attention, perceptual-motor, and social cognition - to such an extent that it interferes with a person’s daily life and activities [National Institute on Aging definition]. Mild cognitive impairment is an intermediate state between normal cognition and dementia.
- Diagnosis requires formal neuropsychiatric testing. In almost all cases, neuropsychiatric testing should be deferred to the outpatient setting given high prevalence of delirium in hospitalized patients.
- Screening for reversible causes:
- TSH for hypothyroidism
- B12 level
- Depression (common in the elderly, symptoms can masquerade as dementia)
- Consider delirium (see delirium vs. dementia below)
- Screening for other conditions is not routinely recommended per the American Academy of Neurology (AAN) but should be considered if there is high clinical suspicion:
- RPR for neurosyphilis
- HIV
- Folate level
- Neuroimaging is not routinely required as an inpatient and can typically be deferred to the outpatient setting unless there is another indication for imaging.
- AAN recommends structural neuroimaging with either a noncontrast head CT or MRI (preferred) in the initial evaluation of all patients with dementia though other guidelines do not recommend routine imaging.
- If imaging is performed, evaluate for structural disease, cerebral atrophy, ventriculomegaly, and signs of ischemic cerebrovascular disease.
Assessment Instruments for Dementia
The Mini-Cog Assessment Instrument is a simple rapid assessment that is relatively uninfluenced by level of education or patient’s English proficiency.
Administration (3 min)
- Instruct patient to remember 3 unrelated words (e.g., apple, blue, happy) and then to repeat the words.
- Draw a large circle on a blank page and instruct the patient to draw the face of a clock in it. After the patient puts the numbers on the clock face, ask him to draw the hands of the clock to read a specific time, such as 11:20. These instructions can be repeated, but no additional instructions should be given. Give the patient as much time as needed.
- Ask the patient to recall the three words from Step 1.
Scoring
Give 1 point for each recalled word. A normal clock has all numbers present in the correct sequence and position with hands that display the correct time.
- 0 = positive screen for dementia.
- 1-2 with abnormal clock = positive screen for dementia.
- 1-2 with normal clock = negative screen for dementia.
- 3 = negative screen for dementia.
Other tests can be considered for a more formal evaluation but should be repeated once a patient is discharged. If limited for time, consult occupational therapy to conduct the assessment:
- MoCA: Montreal Cognitive Assessment - longer (10-15 minutes), better for mild impairment and memory evaluation, copyrighted.
- MMSE: Mini Mental State Examination - shorter (9-10 minutes), more focused on language skills, less sensitive for mild cognitive impairment.
- SLUMS: Saint Louis University Mental Status Exam - shorter (7 minutes), less validation and data on diverse populations.
Management of Patients with Dementia in the Hospital
Start thinking about discharge planning at admission: Will the patient be safe to go home? Should you involve social work and/or APS? Is hospice appropriate (see Palliative Care section)?
Patients with dementia are at increased risk for delirium; institute delirium prevention measures.
- Document dementia and degree of dementia (e.g. MMSE or mini-cog) on discharge summary.
- Dementia increases the risk of all procedures: weigh risks/benefits carefully.
- Many patients with dementia retain decision-making capacity for some procedures. Capacity is decision specific and determined by MD; competence is global and determined by the courts.
- Document patient’s wishes and advance directives. Use your institutional documentation tools where available to make this information accessible to other providers.
- Patients with dementia may not report pain. Consider ATC analgesia, particularly in patients with agitation.
Choosing Wisely
- Do not routinely use antipsychotics to treat behavioral and psychological symptoms of dementia. These medicines offer limited benefit and carry increased risk of stroke and premature death.
- Don’t recommend percutaneous feeding tubes in patients with advanced dementia as there is no mortality benefit; instead offer oral assisted feeding.
Delirium vs. Dementia
Feature |
Delirium |
Dementia |
---|---|---|
Onset |
Acute |
Insidious |
Course |
Fluctuating |
Constant |
Attention |
Disordered |
Usually Preserved |
Alertness |
Disordered |
Usually Preserved |
Hallucinations |
Often Present |
Usually Absent |
Movement |
Often Present |
Usually Absent |
Choosing Wisely
- Avoid using restraints to manage behavioral symptoms of delirium in hospitalized elders.
- Don’t use benzodiazepines or other sedative-hypnotics in older adults as first choice for insomnia, agitation, or delirium.
AGS Choosing Wisely Workgroup. American Geriatrics Society identifies five things that healthcare providers and patients should question. J Am Geriatr Soc 2013 Apr;61(4):622-31.
AGS Choosing Wisely Workgroup. American Geriatrics Society identifies another five things that healthcare providers and patients should question. J Am Geriatr Soc. 2014 May;62(5): 950-60.
Arvanitakis, Zoe, Raj C. Shah, and David A. Bennett. "Diagnosis and Management of Dementia." Jama 322.16 (2019): 1589-1599.
Borson S, Scanlan J, Brush M, et al. The mini-cog: a cognitive “vital signs” measure for dementia screening in multi-lingual elderly. Int J Geriatr Psychiatry 2000;15:1021–1027.
Inouye, SK. Current concepts: delirium in older persons. N Engl J Med 2006;354:1157-1165.
Knopman DS, DeKosky ST, Cummings JL, et al. Practice parameter: diagnosis of dementia (an evidence-based review). Report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology 2001 May 8;56(9):1143-53.
Stewart, Sarah, et al. "A preliminary comparison of three cognitive screening instruments in long term care: The MMSE, SLUMS, and MoCA." Clinical Gerontologist 35.1 (2012): 57-75.