Life expectancy in Alzheimer's disease (AD).

Survival following a diagnosis of AD is important information for health planners, caregivers, patients, and their families. AD is associated with variable, but shortened life expectancy. Knowing the expected survival time may empower people with AD and their families, but clinicians currently have limited predictive information. A better knowledge about prognosis in patients affected by AD and related disorders should be of paramount importance in order to improve care plans and assist in medical decisions, above all for patients in the moderate-severe stages of the disease. Life expectancy for patients with AD can vary between 3 to 10 years. Many studies have tried to identify predictive factors that can be of help for clinicians. The main predictor of life expectancy is the age. Therefore caregivers, patients, and their families could plan on a median life span as long as 7 to 10 years for patients whose conditions are diagnosed when they are in their 60s and early 70s, to only about 3 years or less for patients whose conditions are diagnosed when they are in their 90s. Dementias with prominent psychiatric-behavioral manifestations and gait impairment have a faster progression compared to AD. However the many variables that influence life expectancy make difficult to define prognosis at the bedside and more studies are needed to assist clinicians in they daily routine with patients and caregivers.