Experts from several universities determined their findings from observing 856 participants made to take a variety of neurophysical tests. Further data from the subjects' memory were gathered from family members. Loved ones were also interviewed about the participants' physical capacity to go through daily activities. Medical histories were also taken note of.
The observations lasted from July 2001 to March 2005, with the scientists categorizing the participants based on their findings of symptom severity.
Results told scientists that 22 percent, about 5.4 million people, over 70 are suffering from the loss of memory, thereby affecting their regular routine. This memory lapse, however, was not severe enough to incapacitate the patients.
"It's a huge number," said Brenda Plassman, Ph.D., assistant professor of psychiatry at Duke University. "This is the first time we have an estimate of the number of Americans who have this condition."
The number is exclusive of the 3.4 million Americans suffering from dementia, according to Science Daily.
"These findings illustrate that nearly every family will be faced with the challenges of caring for a family member with some form of memory impairment,". "Even among the people age 71-79, a sizeable number had cognitive impairment. This is an age at which most people expect to have many productive years ahead."
According to the Washington Post, the results surprised experts.
"Five million people is a lot," said Richard Suzman of the National Institute on Aging, responsible for the study's funding. "This is confirmation that this is a very big problem."
Dr. Plassman noted the importance of the awareness towards parents, grandparents, and other older relatives, giving attention to any mental changes that call for added support.
