A more intellectually demanding job may be the key to living longer after developing young-onset dementia, according to health researchers.
Degeneration of the frontal and temporal parts of the brain leads to a common form of dementia affecting people under the age of 65. It results in changes in personality and behavior and problems with language, but does not affect memory.
"[Our] study suggests that having a higher occupational level protects the brain from some of the effects of this disease, allowing people to live longer after developing the disease," said Lauren Massimo, postdoctoral fellow, Penn State College of Nursing.
Previous research has suggested that experiences such as education, occupation and mental engagement help a person develop cognitive strategies and neural connections throughout his or her life.
"People with frontotemporal dementia typically live six to ten years after the symptoms emerge, but little has been known about what factors contribute to this range," said Massimo.
The researchers studied the effects of education and occupation on survival rates in patients with frontotemporal dementia or with Alzheimer's disease, and report their results online today (April 22) in the journal Neurology.
Massimo and colleagues reviewed the medical charts of 83 people who had an autopsy after death to confirm the diagnosis of either frontotemporal dementia or Alzheimer's disease. They also had information about patients' primary occupations.
Occupations were ranked by U.S. Census categories, with jobs such as factory worker and service worker in the lowest level, trade workers and sales people in the next level, and professional and technical workers -- such as lawyers and engineers -- in the highest level.
Researchers determined onset of symptoms by the earliest report from family members of persistently abnormal behavior. Survival was defined as from the time symptoms began until death.
The 34 people autopsied with frontotemporal dementia had an average survival time of about seven years. The people with more challenging jobs were more likely to have longer survival times than those with less challenging jobs.
People in the highest occupation level survived an average of 116 months, while people in the lower occupation group survived an average of 72 months, suggesting that individuals who had been in the professional workforce may live up to three years longer.
The study found that occupational level was not associated with longer survival for the people with Alzheimer's disease dementia. The amount of education a person had did not affect the survival time in either disease.
Massimo is also a postdoctoral fellow at the University of Pennsylvania Frontotemporal Degeneration Center. Ann Kolanowski, Elouise Ross Eberly Professor of nursing and director of the Hartford Center of Geriatric Nursing Excellence at Penn State; Jarcy Zee, associate research scientist, Arbor Research Collaborative for Health, Ann Arbor, Mich.; Sharon X. Xie, associate professor of biostatistics, the department of biostatistics and epidemiology, University of Pennsylvania; Corey T. McMillan, research assistant professor of neurology, Katya Rascovsky, research assistant professor of neurology, and David J. Irwin, instructor of neurology, all at the University of Pennsylvania Frontotemporal Degeneration Center; and Murray Grossman, professor of neurology, director of University of Pennsylvania Frontotemporal Degeneration Center, also collaborated on this research. The U.S. Public Health Service and the Wyncote Foundation supported this work.