Currently, an estimated 5 million people have Alzheimer's disease in the United States, yet this number is projected to triple by 2050, according to researchers at Rush University Medical Center.
The study was published Wednesday in the American Academy of Neurology. It serves as an update of Alzheimer's disease and dementia estimates since the last published findings from 2003 using the 2000 census population, the study reported.
Within the next 40 years, researchers estimate that 13.8 percent of people will develop Alzheimer's, if preventive action is not taken, the study cited. Prevention is significant for aging adults, especially for baby boomers 65 and older.
"If we can come up with something right now and everyone abides by that regimen, it's possible we could reduce the number of expected cases by a few million," said Dr. Jennifer Weuve, assistant professor of medicine at the Rush Institute for Healthy Aging at Rush University Medical Center. z
Weuve with university colleagues conducted the study, which was funded by the Alzheimer's Association and through a NIH/National Institute on Aging grant.
Researchers used data from the Chicago Health and Aging Project, a long-term study, that from 1993 to 2011 gathered information on 10,802 African-American and Caucasian participants age 65 years or older, living on Chicago's South Side.
The current study separated the percentage of adults affected by the Alzheimer's into the following age groups: 65-74 years, 75-84 years and 85 years and over.
By 2050, 18.3 percent of adults age 75-84 will be affected by Alzheimer's compared with 36.6 percent of adults, 85 and over, projected to get the disease. Nearly 7 million of disease sufferers will be 85 years old in 2050, the study found.
Though probability increases drastically with age, those falling within the middle group (75-84) by 2050 are at the highest risk for the disease, Weuve said. This is because this group will be the largest age group in the United States at that time than ever before, she said.
However, she said doesn't find the the results are not surprising. In fact, this analysis simply validates past studies and the urgency for preventive research, starting in midlife, she said.
"This is the sobering point of estimates," Weuve said. "Alzheimer's disease has a long development and progression period. If we're going to intervene in a preventative way, we might have to start early, even in midlife."
As the sixth leading cause of death in America, Alzheimer's disease is the only cause that has no current method of prevention, delaying or cure, according to the Alzheimer's Association.
"The study supports what we've been talking about. [Alzheimer's] is an underrepresented disease in the United States and around the world," said Dr. Maria Carrillo, vice president of medical and scientific affairs at the Alzheimer's Association national headquarters in Chicago.
"Emphasizing that numbers are continuing to rise underscores the urgency of the disease," Carrillo added.
The study mentioned the National Plan to Address Alzheimer's Disease, released by the Obama Administration as part of its 2011 National Alzheimer's Project Act. The Plan is a roadmap to increase research and prevention to reduce the burden of the disease by 2025.
Carrillo said that such an investment makes her optimistic about the future management of the disease.
Still, the impact of Alzheimer's cases goes beyond the federal level. As health care costs rise for people living with the disease, the increased population could unexpectedly overwhelm the number of caregivers available to provide for them.
In 2011, the costs of caregiving, paid or unpaid, was estimated at $210.5 billion. More than 15 million caregivers provided 17.4 billion hours of service to those with dementia-related diseases, according to the Alzheimer's Association.
"It is so important for the Plan to come together, it really is a concerted effort to bring the country's infrastructure together," Carrillo said.
People with Alzheimer's live an average of seven years, but some can live as long as 20 years, she added.
That is why early diagnosis, which is currently difficult to perform, is an ideal way to alleviate the overall strain of the disease on the nation and its caregivers, Weuve said.
Once physicians are able to perform early diagnosis, she said, "People with the disease may be able to function in a way where they can at least have a life that is at least pleasant and not distressing to them or their family."