Dementia is a progressive condition. It presents initially with mild signs and symptoms that usually go unnoticed. These include restlessness and agitation, depression, anxiety, forgetfulness and confusion. Gradually the patient may progress to a state in which he/she complains of tremors, balance and coordination problems, decline of thinking and planning capacity, delusions, distorted memory, impaired speech and difficulty in swallowing and/or eating.

There are no definitive diagnostic tests for dementia. There are however, a number of screening tests available, such as:

• Mini Mental State Examination (MMSE)
• Trail-making test
• Clock-drawing test
• Montreal Cognitive Assessment (MOCA)

Laboratory tests

Routine blood tests may be performed to rule out reversible causes such as tests for vitamin B12 levels, thyroid function tests, complete blood count, liver enzymes, renal function tests, etc.

Imaging 

• CT scan
• PET scan 
• MRI

Other tests

• Brain biopsy

Test results

Diagnosis is based on history physical examination and by the help of test results.

Medications

Currently, no medications have been shown to prevent or cure dementia [8]. Anti-psychotic drugs, cholinesterase inhibitors and anti depressants may be given as needed.

Food and nutrition

Careful assessment for potentially treatable causes of swallowing and appetite problems, honest communication about uncertainties over prognosis and the impact of interventions and ascertainment of individuals' values and beliefs make for better care for people with dementia and better decisions about feeding [9].

Comorbidity (the presence of more than one disease process) is the rule rather than the exception for dementia in elderly persons [7]. Prognosis depends upon the stage of disease.

Stage 1

In this stage, the effected person does not act differently. Just a slight memory loss is evident, which is still more than normal memory loss at old age.

Stage 2

Small changes occur in the affected person’s behaviour. He sometimes takes a bit too long in solving some queries or making a quick decision. He faces problems in terms of time management. But he is still able to lead his life without being taken care of.

Stage 3

In this stage, there are behavioural changes, agitation and restlessness and inability to complete household tasks. The affected person finds it difficult to care for himself.

Stage 4

The disease becomes severe. More loss of memory occurs. Rapid personality changes occur during this stage.

Stage 5

The disease gets more violent with increased memory loss, hallucinations, extreme confusion, agitation and personality changes. The affected person is unable to function without help.

Alzheimer disease is the most common form of dementia [1]. The etiology of AD remains, in large part, unresolved, however, RORA (Retinoic Acid Receptor-related Orphan Receptor) emerges as a gene with a probable central role in the AD pathology/etiology [2].

The main reversible causes of dementia include vitamin B12 deficiency, hypothyroidism, neurosyphilis and Lyme disease. Other causes of dementia include old age, trauma to the head, cognitive impairment, progressive supranuclear palsy, Krabbe’s disease, Nieman Pick disease type C, Ataxia syndrome and acidemias. The production of abnormal level of protein in the brain is also one of the main causes of dementia.

Incidence

Dementia is a fairly common disease and according to the World Alzheimer’s Report 2009, it was estimated that there were 35.6 million cases of dementia worldwide in 2010.

Sex

Studies reveal that dementia is slightly more common in females.

Age

The incidence of dementia increases with age, with dementia affecting 5% of the population older than 65 and 20–40% of those older than 85 [3].

Dementia occurs due to degeneration of neurons in the brain, particularly of the cerebral cortex and later, of other parts like cerebellum. The exact pathophysiology behind dementia is still unclear. Discussed below is the pathogenesis of 2 common etiologies of this condition.

Vascular dementia

Two criteria that have been suggested for the pathologic diagnosis of vascular dementia include:

• Multiple large and/or strategic infarcts in cerebrum [4]. The neuropathology of the dementia is caused by the breakdown of small cerebral vessels (silent microbleeds), that the microbleeds result from pulse-induced damage to the cerebral vessels, and that pulse becomes increasingly destructive with age, because of the age-related stiffening of the aorta and great arteries, which causes an increase in the intensity of the pressure pulse [5]. 
• A threshold of 3 or more microscopic infarcts identified in a systematic screening of cerebral cortex and deep cerebral structures [6].

Alzheimer disease

In this disease, there is progressive atrophy of first the neurons of hippocampus and temporal lobe, and then gradually of the frontoparietal lobes and finally the sensory and motor cortex. It is characterized by the presence of amyloid plaques which are eosinophilic deposits of A beta peptides, and intraneuronal neurofibrillary tangles.

Some of the most promising strategies for the prevention of dementia include vascular risk factor control, cognitive activity, physical activity, social engagement, diet, and recognition of depression [10].

Dementia is a collective term that refers to a decline in brain activity resulting in loss of memory, deceased capacity to think and make logical decisions, impaired speech and motor functioning and delusions. It is not a disease itself, instead it is a collection of many disorders which may be alike or, in many cases, differ from each other. Dementia is commonly associated with Alzheimer disease, but it occurs in many more diseases and conditions. It occurs mostly at the age of 65-75 and is known to be the disease of the old.

However, if a person gets old and becomes forgetful, it does not mean he has dementia. This is because some memory loss in old age is quite natural. But along with memory loss, if that person’s actions are different, for example, in the way of his communication towards others or his decisions are somewhat absurd, this may point towards dementia and thorough testing and evaluation by the clinician is in order.

Definition

Dementia is a term used to describe brain disorders in which there is progressive loss of memory, thinking and motor ability.

Cause

The most common causes of dementia include old age, Alzheimer disease and vascular disorders. Some people may be genetically prone to this condition.

Symptoms

Dementia presents initially with restlessness, slight memory loss and depression. It may progress to severe memory loss, confusion, hallucinations, delusions, tremors, impaired speech, motor dysfunction and difficulty in eating. In the end, the affected person is unable to function on his own.

Treatment

Dementia has no cure. It may be symptomatically treated with proper diet and some medication.

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