August 19, 2003
A new analysis confirms that the number of Americans expected to become afflicted with Alzheimer's disease in the coming decades is likely to snowball unless new discoveries prompt the development of effective treatment and preventive measures for this devastating memory-robbing ailment.
"Alzheimer's disease is becoming an increasingly major medical problem in the United States and worldwide," says nobel laureate Paul Greengard, PhD, Director of the Fisher Center for Alzheimer's Research at The Rockefeller University. "The new data estimating the number of likely Alzheimer's victims in coming decades underscores the importance of supporting research into the causes, prevention and treatment of Alzheimer's disease," he says.
Combining data from the most recent U.S. Census and other government data and an analysis of three Chicago neighborhoods, researchers at Rush-Presbyterian St. Luke's Medical Center estimated that in the year 2000, 4.5 million Americans had Alzheimer's.
Most of those cases--some 53 percent, or 2.4 million--were in men and women aged 75 to 84. Another 40 percent, or 1.8 million, were in seniors age 85 and up, while only about 7 percent, or 300,000, were in those aged 65 to 74. Far fewer cases occur in younger individuals.
Of those 4.5 million cases, 48 percent were classified as mild," 31 percent as "moderate," and 21 percent as "severe." Doctors use these categories to define the progressively more incapacitating stages of the disease.
Up to 16 Million by 2050
The number of Alzheimer's diagnoses is expected to increase rapidly in coming decades. The researchers calculated that by 2020, there would be 27 percent more cases, and by 2030, 70 percent more. They estimated that the caseload would nearly triple, to an astounding 13.2 million people, by 2050. Their estimates for that year ranged from a low of 11.3 million to a high of 16 million.
These numbers shore up earlier estimates of the high prevalence of Alzheimer's. The number of cases, however, continues to be difficult to tally because so many go undiagnosed and uncounted.
The rise in cases is due in large part to the rapid aging of the U.S. and the fact that Americans are living longer. Advancing age remains the single greatest risk factor for contracting Alzheimer's disease. The researchers believe that by 2050, there will be 8 million Americans aged 85 and up, four times the current number, and 4.8 million aged 75 to 84, twice the current number. The number of Americans 65 to 74 is expected to remain fairly constant at 300,000 to 500,000.
"Alzheimer's is not just an American problem," says Samuel E. Gandy, M.D., Ph.D., Chairman of the Scientific Advisory Board, Fisher Center for Alzheimer's Research Foundation. "Worldwide, there are many more millions of men and women afflicted with the disease. The figures underline the urgent need for more funding into the basic causes underlying Alzheimer's and related brain ailments so that effective treatment and prevention strategies can be found," Dr. Gandy states.
The study was published in the August 2003 issue of the Archives of Neurology, a respected journal for physicians.
By www.ALZinfo.org, The Alzheimer's Information Site. Reviewed by Samuel E. Gandy, M.D., Ph.D., Chairman of the Scientific Advisory Board, Fisher Center for Alzheimer's Research Foundation.
"Alzheimer's Disease in the US Population: Prevalence Estimates Using the 2000 Census." Liesi E. Hebert, ScD; Paul A. , ScD; Julia L. Bienias, ScD; David A. Bennett, MD; Denis A. Evans, MD. Archives of Neurology 2003; Volume 60, Number 8:1119-1122.