Survival After Alzheimer's Diagnosis
Early Age of Diagnosis Linked to Relatively Shorter Life Span
Nov. 18, 2002 -- A diagnosis of Alzheimer's is devastating at any age, but a new study shows the age of diagnosis can have a big impact on how quickly the disease takes its toll. Researchers found people diagnosed with Alzheimer's in their 60s and early 70s had a shorter life span by about 15 years yet those diagnosed at an older age had a shorter life span by only about two to three years.
The study appears in the November issue of the Archives of Neurology.
Researchers say the results confirm earlier indications that the life span of people with Alzheimer's disease (AD) depends crucially on the age of diagnosis, and that information is vital to both caregivers and health officials.
"Information on survival following a diagnosis of AD is important, not only for predicting future prevalence of the disease but also for planning the resources necessary to care for patients during a life span of increasing disability," writes Ron Brookmeyer, PhD, of the Johns Hopkins University Bloomberg School of Public Health, and colleagues.
The researchers say the prevalence of Alzheimer's disease is expected to quadruple over the next 50 years, when the disease is projected to affect one in 45 Americans.
The study looked at 921 patients age 55 over a 15-year follow-up period who were enrolled in the Baltimore Longitudinal Study of Aging from 1985 to 1999.
Researchers found the average survival time after a diagnosis of AD depended strongly on the patient's age.
For example, the average survival time for a person diagnosed with the disease at age 65 was 8.3 years, 15 years shorter than the average, or a 65% reduction in lifespan. A diagnosis of AD at age 90 decreased the average life span for that age by two to three years, or a reduction in remaining years of only 39%. So the older the diagnosis, the less of an impact on survival time; the younger the age at diagnosis, the more of an impact on lifespan the disease had.
No differences were found between men and women in terms of survival.
The researchers say several strategies, such as hormone replacement and anti-inflammatory drug therapy, are currently being studied that may help prevent or delay the onset of Alzheimer's. If those therapies are proven effective, they could have a significant impact in reducing the level of disability associated with the disease as well as prolonging life span after diagnosis.
SOURCE: Archives of Neurology, November 2002. -->