Dementia is known as the leading public health and gerontological problem of the new era, because of the increasing number of elderly population and it becomes a priority in the care for the elderly. The main characteristic is the impossibility of doing the daily activites and because of that it gradually leads to failure in social and intelectual life of the person. The most common type is the Alzheimer's dementia as a consequence of the Alzheimer's disease, which accounts for 2/3 of all dementias. The German neurologist and pathologist Alois Alzheimer was the first who described the disease, in 1906. The disease was named after him. Despite all of the new cognitions about AD, the cause of the disease and the adequate prevention are still unknown. The existing treatment is still just simptomatic. It is known that there are two types and three stadiums of this disease. The rare type is more frequent and with later onset. It affects individuals who don't have the predispositon for the disease. The family type appears in 5 to 15% of cases, half of the cases have an early beginning before the age of 65 and they are connected to the genetic mutations. It has been identyfied that the genetic mutations on the first, 12th, 14th, 19th, 21st chromosome have the impact on the early and late appearance of the Alzheimer disease. The diagnosis of the AD comes with a lot of social and emotional difficulties, not just to the sick person, but to her family too. In a person with changed cognitive abbilities, such as in a person with dementia, the communication becomes harder, and with the progress of the disease, the communication can dissapear. Therefore, it is important to emphasize the role of the family, the caregivers and the society in the life of the person suffering from dementia and the impact of the disease on their physical and mental health and the social and economic situation.