Dementia is a disease or group of illnesses caused by damage to brain cells. Thus, a person's mental capacities are reduced, and many skills such as memory, language, problem-solving, and thinking are affected emotionally, as well as problems with normal communication, behavior, and normal functioning. The severity of the condition ranges from mild symptoms to severe illnesses that can interfere with a patient's daily activities.

The incidence of dementia is rapidly increasing worldwide, especially among the elderly. Due to the rapidly aging population, the number of people living with this disease is expected to triple over the next 30 years, leading to an increase in the socioeconomic burden associated with dementia. In 2003, dementia was the fifth and eighth leading cause of death for women and men over the age of 65 in the United States, respectively.