Alzheimer’s Bigger Killer Than We Realize, Study Says

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Alzheimer’s disease kills more Americans than we realize, researchers say.

Death certificates often do not list dementia as the underlying cause of death. Instead, the immediate cause, like pneumonia, is listed, obscuring Alzheimer’s-related deaths, according to Bryan D. James of Rush University Medical Center in Chicago and lead author of a study published in the journal Neurology.

The researchers followed 2,566 people between the ages 65 and older who had yearly tests for dementia. After about eight years, 1,090 of the participants died, and 559 of the participants who did not have dementia at the start of the study developed Alzheimer’s disease. The death rate among participants was four times higher after a diagnosis of Alzheimer’s in people between 75 to 84, and almost three times higher in people over age 85.

The researchers say this equates to an estimated 503,400 deaths from Alzheimer’s in Americans over age 75 in 2010. This is six times greater than the 83,494 deaths from Alzheimer’s disease the CDC reported. Currently, Alzheimer’s is the sixth leading cause of death in the U.S., according to the CDC. Heart disease and cancer are numbers one and two, at 597,689 and 574,743 deaths, respectively.

“Determining the true effects of dementia in this country is important for raising public awareness and identifying research priorities regarding this epidemic,” said James in a statement.

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