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. Although dementia is far more common in the geriatric population, it may occur in any stage of adulthood. This age cutoff is defining, as similar sets of symptoms due to organic brain dysfunction are given different names in populations younger than adulthood (see, for instance, developmental disorders).
Dementia is a non-specific illness syndrome (set of symptoms) in which affected areas of cognition may be memory, attention, language, and problem solving. Higher mental functions are affected first in the process. 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 are due to causes which may presently be reversed with treatment. Causes include many different specific disease processes, in the same way that symptoms of organ dysfunction such as shortness of breath, jaundice, or pain are attributable to many etiologies. Without careful assessment of history, the short-term syndrome of delirium can easily be confused with dementia, because they have many symptoms in common. Some mental illnesses, including depression and psychosis, may also produce symptoms which must be differentiated from both delirium and dementia
Diagnosis
Proper differential diagnosis between the types of dementia (cortical and subcortical - see below) will require, at the least, referral to a specialist, e.g. a geriatric internist, geriatric psychiatrist, neurologist, neuropsychologist or geropsychologist. However, there exist some brief tests (5-15 minutes) that have reasonable reliability and can be used in the office or other setting to screen cognitive status for deficits which are considered pathological. Examples of such tests include the abbreviated mental test score (AMTS), the mini mental state examination (MMSE), Modified Mini-Mental State Examination (3MS),[2] the Cognitive Abilities Screening Instrument (CASI),[3] and the clock drawing test.[4]. 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 highly depressed or in great pain will not be expected to do well on many tests of mental ability.
Subcortical dementias
* Dementia due to Huntington's disease
* Dementia due to Hypothyroidism
* Dementia due to Parkinson's disease
* Dementia due to Vitamin B1 deficiency
* Dementia due to Vitamin B12 deficiency
* Dementia due to Folate deficiency
* Dementia due to Syphilis
* Dementia due to Subdural hematoma
* Dementia due to Hypercalcaemia
* Dementia due to Hypoglycemia
* AIDS dementia complex
* Pseudodementia (associated with clinical depression and bipolar disorder)
* Substance-induced persisting dementia (related to psychoactive use and formerly Absinthism)
* Dementia due to multiple etiologies
* Dementia due to other general medical conditions (i.e. end stage renal failure, cardiovascular disease etc.)
* 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.
Treatment
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 inhibitors 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.[15]
Medications
* Acetylcholinesterase inhibitors
Tacrine (Cognex), donepezil (Aricept), galantamine (Razadyne, Memeron), 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.[16]
* N-methyl-D-aspartate Blockers. Memantine (Namenda) is a drug representative of this class. It can be used in combination with acetylcholinesterase inhibitors.
Off label
* Amyloid deposit inhibitors
Minocycline and Clioquinoline, antibiotics, may help reduce amyloid deposits in the brains of persons with Alzheimer disease.[17]
* Antipsychotic drugs
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.[18][19]
* Antidepressant drugs
Depression is frequently associated with dementia and generally worsens the degree of cognitive and behavioral impairment. Antidepressants may be helpful in alleviating cognitive and behavior symptoms by reuptaking neurotransmitter regulation through reuptake of serotonin, noradrenaline and dopamine.
* Antianxiety drugs
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 primarily 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.
Prevention
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.[20]
Furthermore, there are medications which might contribute to prevent the onset of dementia, including hypertension medications, anti-diabetic drugs, and NSAIDs.[21]
Studies published in US journals suggested that a Mediterranean diet or long-term beta-carotene supplements could ward off dementia.[22]
Risk to self and others
Driving with dementia could lead to severe injury or even death to self and others. Doctors should advise appropriate testing on when to quit driving.[23]
Florida's Baker Act allows law enforcement and the judiciary to force mental evaluation for those suspected of suffering from dementia or other mental incapacities
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