Dementia is a syndrome due to a disease of the brain, which is of chronic progressive nature in which there is disturbance of multiple higher cortical functions, including memory, thinking, orientation, comprehension, calculations, learning capacity, language and judgement. Impairment of cognitive function are commonly accompanied and occasionally preceded by disorientation in emotional control, social behaviour or motivation. Dementia produces an appreciable decline in intellectual functioning and usually interferes with personal activities of daily living such as washing, dressing, eating, personal hygiene and self care. The disorder can be progressive or static, permanent or reversible. Approximately 15 percent of people with dementia have reversible illnesses if treatment is initiated before irreversible damage takes place. Dementia can further be categorised into the following :

• Alzheimer’s disease – is the most common form of dementia, accounting for around two –thirds of cases. It causes a gradual decline in cognitive abilities, often beginning with memory loss. It is the cause of 60-70% of cases of dementia. The most common symptom is difficulty in remembering recent events. As the disease progresses the symptoms worsens; including difficulties in language, disorientation, mood swings, self neglect and behavioural issues. This disease begins in the late middle adult life or sometimes even earlier but the incidence is higher in the later life. In the cases with onset before the age of 65-70, there is likelihood of a family history of similar dementia. In the cases with late onset, the course tend to be slower with impairment of higher cortical functions. Dementia in Alzheimer’s disease begins before the age of 65 years, usually with slow progression of symptoms.

• Vascular Dementia- is cognitive impairment caused by damage in the blood vessels in the brain. It can be caused by a single stroke, or by several strokes occurring over time. The symptoms can begin suddently after a stroke, or may begin gradually as blood vessel disease worsens.The symptoms vary depending on the location and size of brain damage.It may affect just one or a few specific cognitive functions. Vascular dementia may appear similar to Alzheimer’s disease and a mixture of Alzheimer’s disease and vascular dementia is fairly common.

• Mixed Dementia-in this condition Alzheimer’s disease and vascular dementia occur simultaneously. The combination of the two types of dementia most commonly occurs in people with advanced age, often indicated by cardiovascular disease and the symptoms that get worse slowly with time.

The less forms of dementia includes; dementia in Pick’s disease, Lewy bodies, Parkinson’s Disease Dementia, Huntington’s disease, Fronto-temporal dementia (FTD) AND Creutzfeldt-Jakob disease. Psychosocial management of dementia includes cognitive stimulation therapy, cognitive remediation and Reminiscence therapy. Medications are generally indicated in cases where usual forgetfulness or age related cognitive decline is differentiated from minor neuro-cognitive impairment based on certain psychological tests or neuroimaging like mri or ct scan. 

Early treatment generally leads to a better prognosis in form of maintaining sufficient quality of life in later stages. Also reversible causes due to effect of substance like alcohol, long term use of sleeping pills, vitamin deficiencies, effect of certain medications like antihypertensives or blood thinners or opium may need supportive individualised treatment. In cases where treatment is started in later age the prognosis becomes poor.