Alzheimer’s disease also known as Alzheimer disease is a neurological condition characterized by progressive loss of memory, intelligence, ability to judge and reason properly, blunting of social skills, to such an extent that leading normal life becomes almost impossible.This is the most common type of dementia, others being Lewy body dementia, vascular dementia, frontotemporal dementia etc. The disease was first described in the year 1906 by German psychiatrist Alois Alzheimer and hence called Alzheimer’s disease. Usually people above 65 years of age are diagnosed with the disease however the disease may affect younger people also. It was estimated that in the year 2006 about 26.6 million people were suffering from Alzheimer disease and by the year 2050 1 in 85 people are predicted to be suffering from the disease.

Initially only there is short term memory loss which gradually progress to long term memory loss, confusion, irritability, frustration, difficulty in writing, reading and also in speech etc. Alzheimer disease is classified as a neurodegenerative disorder characterized by shrinkage of brain tissue and certain specific abnormalities in the brain tissue namely plaques and tangles.The greatest risk factor associated with Alzheimer disease is aging. It is estimated that about half of people over 85 years of age suffer from Alzheimer disease. There is no cure for Alzheimer disease; the goal of treatment is to relieve symptoms as much as possible and to provide safe, healthy environment.
Symptoms
Initially Alzheimer disease starts with increased forgetfulness and confusion; gradually with time these initial symptoms worsen affecting the short term memory. The affected people initially complain of increased forgetfulness and confusion. However sometimes they fail to notice these symptoms; rather it is the close ones like friends, family members, colleagues, they point out the change in usual behavioral pattern.

The most common changes in the usual behavioral pattern of an affected person include :
Memory loss: Forgetfulness is a common issue in everyone’s life; forgetting names of people or where the key has been kept is very common. But loss of memory in Alzheimer Disease becomes persistent and gradually worsens over time interrupting daily life. Common presenting symptoms indicating memory loss include repetition of same questions again and again unintentionally, difficulty in remembering conversations, appointments and other commitments regularly, frequent misplacing of day to day used objects and often keeping them at unusual places, gradually forgetting names of closed ones as well as regularly used objects.
Disorientation: it is a common problem in Alzheimer disease; the affected person looses his or her ability to understand the concept of time and space. He or she also becomes disorientated regarding the surroundings leading to repeated episodes of getting lost in familiar surroundings
Difficulty in speaking and writing: memory loss may worsen to such an extent that one forgets the words both in terms of speaking as well as in writing thus making him or her unable to communicate with others.
Deterioration of reasoning capacity: it interferes with one’s ability to concentrate, use reasoning or logic and also to judge a situation. Eventually the affected person face difficulty in understanding abstract concepts like numbering thus becomes incapable of managing financial matters.
Poor judgmental capacity: these patients cannot respond adequately which require immediate judgment.Difficulty in performing basic tasks like dressing or bathing even eating.Thus common changes in the personality include increased depression, anxiety, frustration, irritability, aggressive behavior etc.Despite progression of the disease, skills acquired during early life usually remains intact and are lost only during the advanced stage of the disease. Hence during the later stage of the disease persuasion of these skills might help the patient to stick to normal routine to some extent.
Causes
Alzheimer disease is thought to occur due to complex interplay among different genetic, environmental and lifestyle pattern. Only in 5% patients of Alzheimer disease characteristic genetic change is present which makes the occurrence of the disease inevitable. Although the exact cause is yet to be established the abnormal changes in the brain in an Alzheimer disease patient is well known. Apart from shrinkage of brain tissue, death of nerve cells, there are plaques and tangles. Plaques are the clumps of beta amyloid proteins which accumulate in the cells leading to their death. For normal functioning of brain cells transport proteins are known as tau proteins are required. In Alzheimer disease the tau protein strands are twisted forming abnormal tangles in the brain cells.
Risk factors
Other than advanced age other common risk factors include being females, family history of Alzheimer disease, suffering from mild degree of cognitive impairments, past history of head injury, maintaining certain lifestyles like sedentary life style no exercise, chronic smoking, elevated blood pressure, abnormal lipid metabolism etc.Pursuing certain hobbies like playing musical instruments, mentally challenging jobs, extrovert attitude, increased interaction with people etc.
Treatment
Till date there is no cure for Alzheimer disease however symptoms may be relieved to some extent by drugs like cholinesterase blockers like donepezil, galantamine, memantine etc.Measures to do exercise regularly, consuming balanced diet rich in high calorie, adequate water, juices etc are also helpful.