''Dementia'' (from
Latin ''de-'' "apart, away" + ''
Mens '' (
Genitive ''mentis'') "mind") is the progressive decline in
Cognitive Function due to damage or
Disease in the
Brain beyond what might be expected from normal
Aging .
Particularly affected areas may be
Memory ,
Attention ,
Language , and
Problem Solving . Especially in the later stages of the condition, affected persons may be
Disoriented in time (not knowing what day of the week, day of the month, month, or even what year it is), in place (not knowing where they are), and in person (not knowing who they are).
Symptoms of dementia can be classified as either reversible or irreversible depending upon the
Etiology of the disease. Less than 10 percent of cases of dementia have been reversed. Dementia is a non-specific term encompassing many disease processes, just as
Fever is attributable to many etiologies.
Without careful assessment,
Delirium can easily be confused with dementia and a number of other
Psychiatric Disorders because many of the signs and
Symptoms are also present in dementia (as well as other
Mental Illnesses including
Depression and
Psychosis ).
American Family Physician, March 1, 2003 Delirium
The
Prevalence of dementia is rising as the global
Life Expectancy is rising. Particularly in Western countries, there is increasing concern about the economic impact that dementia will have in future, older populaces. In Australia, the 2006 estimated prevalence of dementia is 1.03% of the population as a whole. Though reports of some of the longest living people claim them to be free of it (e.g.
Yone Minagawa ), it is a disease which is strongly associated with age; 1% of those aged 60-65, 6% of those aged 75-79, and 45% of those aged 95 or older suffer from the disease.
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The final diagnosis of dementia is made on the basis of the clinical picture, increasingly with neuroimaging results for backup. For research purposes, the diagnosis depends on both a clinical diagnosis and a pathological diagnosis (i.e., based on the examination of brain tissue, usually from
Autopsy ).
Proper differential diagnosis between the types of dementia (see below) will require, at the least, referral to a specialist, e.g. a geriatric internist, geriatric psychiatrist, neurologist, neuropsychologist or geropsychologist. However, there are some brief (5-15 minutes) tests that have good reliability and can be used in the office or other setting to evaluate cognitive status. Examples of such tests include the
Abbreviated Mental Test Score (AMTS), the
Mini Mental State Examination (MMSE), Modified Mini-Mental State Examination (3MS)Teng E L, Chui H C. The Modified Mini-Mental State (3MS) examination. J Clin Psychiatry 1987;48:314–18. PMID 3611032, the Cognitive Abilities Screening Instrument (CASI)Teng E L, Hasegawa K, Homma A, et al. The Cognitive Abilities Screening Instrument (CASI): a practical test for cross-cultural epidemiological studies of dementia. Int Psychogeriatr 1994;6:45–58. PMID 8054493, and the clock drawing test
2.
An
AMTS score of less than six (out of a possible score of ten) and an
MMSE score under 24 (out of a possible score of 30) suggests a need for further evaluation. Scores must be interpreted in the context of the person's educational and other background, and the particular circumstances (for example, a person in great pain will not be expected to do well on many tests of mental ability).
See Also: Mini-mental state examination
The
U.S. Preventive Services Task Force (USPSTF) reviewed tests for cognitive impairment and concluded
3:
- MMSE
: sensitivity 71% to 92%
: specificity 56% to 96%
A copy of the
MMSE can be found in the appendix of the original publication.
4
A copy of the 3MS is online.
5 A
Meta-analysis concluded that the Modified Mini-Mental State (3MS) examination has:Cullen B, O'Neill B, Evans JJ, Coen RF, Lawlor BA. A review of screening tests for cognitive impairment.
J Neurol Neurosurg Psychiatry. 2007 Aug;78(8):790-9. Epub 2006 Dec 18. PMID 17178826
: sensitivity 83% to 94%
: specificity 85% to 90%
See Also: abbreviated mental test score
A
Meta-analysis concluded:
: sensitivity 73% to 100%
: specificity 71% to 100%
Many other tests have been studied
67 8 including the clock-drawing test
example form ). Although some may emerge as better alternatives to the MMSE, presently the MMSE is the best studied. However, access to the MMSE is now limited by enforcement of its copyright (
Details ).
Further evaluation includes retesting at another date, and administration of other (and sometimes more complex) tests of mental function, such as formal neuropsychological testing.
Routine blood tests are also usually performed to rule out treatable causes. These tests include
Vitamin B12 ,
Folic Acid ,
Thyroid-stimulating Hormone (TSH),
C-reactive Protein ,
Full Blood Count ,
Electrolyte s,
Calcium ,
Renal Function and
Liver Enzyme s. Abnormalities may suggest vitamin deficiency, infection or other problems that commonly cause confusion or disorientation in the elderly. Chronic use of substances such as
Alcohol can also predispose the patient to cognitive changes suggestive of dementia.
A
CT Scan or
Magnetic Resonance Imaging (MRI scan) is commonly performed, although these modalities (as is noted below) may not have optimal sensitivity for the diffuse metabolic changes associated with dementia in a patient who shows no gross neurological problems (such as paralysis or weakness) on neurological exam. CT or MRI may suggest
Normal Pressure Hydrocephalus , a potentially reversible cause of dementia, and can yield information relevant to other types of dementia, such as infarction (
Stroke ) that would point at a vascular type of dementia. Recently, the functional neuroimaging modalities of
SPECT and
PET have shown quite similar ability to diagnose dementia as clinical exam (PMID 16785801). SPECT's ability to differentiate vascular type from Alzheimer disease types of dementias appears to be superior to clinical exam (PMID 15545324).
- Dementia not otherwise specified (used in cases where no specific criteria is met)
Dementia and early onset dementia have been associated with neurovisceral porphyrias. Porphyria is listed in textbooks in the differential diagnosis of dementia. Because acute intermittent porphyria, hereditary coproporphyria and variegate porphyria are aggravated by environmental toxins and drugs the disorders should be ruled out when these etiologies are raised.
Except for the treatable types listed above, there is no cure to this illness, although scientists are progressing in making a type of medication that will slow down the process.
Cholinesterase Inhibitor s are often used early in the disease course. Cognitive and behavioral interventions may also be appropriate. Educating and providing emotional support to the
Caregiver (or carer) is of importance as well (''see also
Elderly Care '').
A
Canadian study found that a lifetime of
Bilingualism has a marked influence on delaying the onset of dementia by an average of four years when compared to
Monolingual patients. The researchers determined that the onset of dementia symptoms in the monolingual group occurred at the mean age of 71.4, while the bilingual group was 75.5 years. The difference remained even after considering the possible effect of cultural differences,
Immigration , formal
Education , employment and even
Gender as influences in the results.
9
Snoezelen Rooms that provide patients with a soothing and stimulating environment of light, color, music and scent have been used in the therapy of dementia patients.
Tacrine (Cognex),
Donepezil (Aricept),
Galantamine (Reminyl), and
Rivastigmine (Exelon) are approved by the United States Food and Drug Administration (FDA) for treatment of dementia induced by Alzheimer disease. They may be useful for other similar diseases causing dementia such as Parkinsons or vascular dementia.Lleo A, Greenberg SM, Growdon JH. Current pharmacotherapy for Alzheimer's disease.Annu Rev Med. 2006;57:513-33. Review. PMID 16409164
- N-methyl-D-aspartate Blockers
Drugs within the class known as
N-methyl-D-aspartate (NMDA) blockers include
Memantine (Namenda), which has been approved by the FDA for the treatment of moderate-to-severe dementia.
- Amyloid deposit inhibitors
Minocycline and
Clioquinoline , antibiotics, may help reduce
Amyloid deposits in the brains of persons with Alzheimer disease.Choi, Y., Kim, H.S., Shin, K.Y., Kim, E.M., Kim, M., Kim, H.S., Park, C.H., Jeong, Y.H., Yoo, J., Lee, J.P., Chang K.A., Kim S., & Suh, Y.H. Related Minocycline Attenuates Neuronal Cell Death and Improves Cognitive Impairment in Alzheimer's Disease Models. ''Neuropsychopharmacology''. 2007 Apr 4; PMID 17406652
Haloperidol (Haldol),
Risperidone (Risperdal),
Olanzapine (Zyprexa), and
Quetiapine (Seroquel) are frequently prescribed to help manage
Psychosis and
Agitation . Treatment of dementia-associated psychosis or agitation is intended to decrease psychotic symptoms (for example, paranoia, delusions, hallucinations), screaming, combativeness, and/or violence.Wei, Z., Mousseau, D.D., Dai, Y., Cao, X., Li, X.M. (2006). Haloperidol induces apoptosis via the sigma2 receptor system and Bcl-XS. ''Pharmacogenomics J. 6''(4):279-88. Epub 2006 Feb 7. PMID 16462815Wang, H., Xu, H., Dyck, L.E., & Li, X.M. (2005). Olanzapine and quetiapine protect PC12 cells from beta-amyloid peptide(25-35)-induced oxidative stress and the ensuing apoptosis. ''Journal Neuroscience Res, 81''(4):572-80. PMID 15948179
Depression is frequently associated with dementia and generally worsens the degree of
Cognitive and
Behavioral impairment.
Antidepressant s may be helpful in alleviating cognitive and behavior symptoms by reuptaking
Neurotransmitter regulation through reuptake of
Serotonin ,
Noradrenaline and
Dopamine .
Many patients with dementia experience
Anxiety symptoms. Although
Benzodiazepines like
Diazepam (Valium) have been used for treating anxiety in other situations, they are often avoided because they may increase agitation in persons with dementia or are too sedating.
Buspirone (Buspar) is often initially tried for mild-to-moderate anxiety.
Selegiline , a drug used primarilly in the treatment of Parkinson's disease, appears to slow the development of dementia. Selegiline is thought to act as an
Antioxidant , preventing
Free Radical damage. However, it also acts as a stimulant, making it difficult to determine whether the delay in onset of dementia symptoms is due to protection from free radicals or to the general elevation of brain activity from the stimulant effect.
See Also: Prevention of dementia
Since there is no cure for dementia, the best an individual can do is to prevent it from developing in the first place.
The main method to prevent dementia is to live an active life, both mentally and physically. It appears that the regular moderate consumption of alcohol (beer, wine or distilled spirits) may reduce risk. Mulkamal, K.J., ''et al''. Prospective study of alcohol consumption and risk of dementia in older adults. ''Journal of the American Medical Association'', 2003 (March 19), ''289'', 1405-1413; Ganguli, M., ''et al''. Alcohol consumption and cognitive function in late life: A longitudinal community study. ''Neurology'', 2005, ''65'', 1210-12-17; Huang, W., ''et al''. Alcohol consumption and incidence of dementia in a community sample aged 75 years and older. ''Journal of Clinical Epidemiology'', 2002, ''55(10)'', 959-964; Rodgers, B., ''et al''. Non-linear relationships between cognitive function and alcohol consumption in young, middle-aged and older adults: The PATH Through Life Project. ''Addiction'', 2005, ''100(9)'', 1280-1290; Anstey, K. J., ''et al''. Lower cognitive test scores observed in alcohol are associated with demographic, personality, and biological factors: The PATH Through Life Project. ''Addiction'', 2005, ''100(9)'', 1291-1301; Espeland, M., ''et al''. Association between alcohol intake and domain-specific cognitive function in older women. ''Neuroepidemiology'', 2006, ''1(27)'', 1-12; Stampfer, M.J., ''et al'. Effects of moderate alcohol consumption on cognitive function in women. ''New England Journal of Medicine'', 2005, ''352'', 245-253; Ruitenberg, A., ''et al''. Alcohol consumption and risk of dementia: the Rotterdam Study. ''Lancet'', 2002, ''359(9303)'', 281-286; Scarmeas, N., ''et al''. Mediterranean diet and risk for Alzheimer’s disease. ''Annals of Neurology'', 2006 (published online April 18, 2006).
Furthermore, there are medications which might contribute to prevent the onset of dementia, including hypertension medications, anti-diabetic drugs and NSAIDs
West Virginia Department of Health and Human Resources (with further links to experiments respectively) .
