Researchers got together 288 people, 162 women and 126 men, from one community in Sweden (Goteborg) to get the answers.
When the study began the participants did not have any form of dementia .
The participants were tested up to 12 times from age 70 until their death, as researchers gauged how well they did in three categories.
The average age of death was 84.
Participants were measured in these three areas:
Verbal ability, or how well they were able to understand ideas expressed in words with synonyms.
Spatial ability was tested using two-colored blocks to build a replica of a model design shown.
Perceptual speed, or how fast they were able to match a certain figure in a line of other figures.
Here are the results of when those three skills started to decline:
- When it came to verbal ability, participants showed a "change point" for decline nearly seven years (6.58) before they died.
- In spatial ability, the change point came almost eight years before death. (7.83)
- On perceptual speed, a difference was seen nearly 15 years before dying. (14.83)
"These changes are different and separate from the changes in thinking skills that occur as people get older," study lead author Valgeir Thorvaldsson, MSc, of Goteberg University in Sweden, says in a news release.
"We found accelerated changes in people's mental skills that indicated a terminal decline phase years before death."
Is there something we can do about it? Are there any reasons why this may be happening?
Thorvaldsson says health conditions could contribute to the decline. "Cardiovascular conditions such as heart disease or dementia that is too early to be detected could be factors."
He says that "increased health problems and frailty in old age often lead to inactivity, and this lack of exercise and mental stimulation could accelerate mental decline."
Thorvaldsson speculates that physicians may want to watch for changes in verbal ability, like staying sharp at recognizing ideas expressed in words, as a warning sign of declining health since the study found that verbal skills took a sharper decline in the years before death.
The findings appear in the Aug. 27 online edition of Neurology.
By Kelley Colihan
Reviewed by Louise Chang
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