The San Jose Mercury News had an interesting article about recent research into dementia. In 1980, about 2.8 million Americans were diagnosed with Alzheimer’s disease — the most common form of dementia. But with better recognition, longer life expectancies and advanced treatment for other diseases such as cancer, that figure has nearly doubled in 2010, to 5.3 million, according to Elizabeth Edgerly, a chief program officer with the Alzheimer’s Association, a national advocacy group. In all, 42 percent of people 85 and older will get Alzheimer’s, Edgerly said.
"The ability to recognize dementia has improved over the last 20 years," said Rick Kovar, emergency services manager for the Contra Costa County Sheriff’s Office. "The science behind searching for people with Alzheimer’s has become efficient and scientific."
Dementia affects the brain in several ways. People lose short-term memory, the ability to communicate, express emotions and follow a conversation. They have severe mood shifts, and lose the ability to reason, problem-solve, sense danger and judge visual spacing.
"Wandering is one of the most common behaviors associated with dementia," Edgerly said. Sixty percent of people with dementia will wander at least once. Of those, 20 percent wander repeatedly.
The team studies "lost person behavior," which is different for various groups of people who are lost. For example, an elderly person with dementia behaves differently than a missing hiker or child. A person with dementia may not recognize objects such as bodies of water or bushes, and walk right into them. They go until they become stuck. When they hit a barrier that blocks their way, they keep running into it until they find a way around, a phenomenon search professionals call "ping-pong." They tend to travel in as straight a line as possible.
Another well-known characteristic is patients trying to return to a place that may no longer exist. Wanderers typically travel up to 2 miles away from their starting point, which is why the initial search perimeter starts at that distance and expands as needed.
Wanderers are more susceptible to becoming victims of crime, and because of their age they may be seriously injured in falls or made ill by poor weather.