(NBC News) Alzheimer's Disease is listed officially as the sixth leading cause of death in the United States, but new information suggests the disease contributes to far more deaths than what has been reported.
During the last dozen or so years of his life Michael Steinberg suffered from Alzheimer's, a progressive disease that slowly steals memory, breaks down the body and eventually leads to death.
It was the root cause of what ended his life according to his daughter, Carol.
"But the death certificate doesn't say that. What the death certificate says is that he died of cardiac arrest, which was caused by an infection, which was caused by bed sore," she says.
The Steinbergs' story illustrates how Alzheimer's may be vastly under-reported on death certificates, documents that agencies like the Centers for Disease Control use to identify major causes of death in the United states.
"Many people do not conceive of Alzheimer's as a fatal disease, when in fact it is," says Dr. Bryan James.
Dr. James and colleagues at Rush University Medical Center in Chicago analyzed data on more than 2,500 elderly adults, digging deeper than what was written on death certificates.
Their calculations show that Alzheimer's contributes to far more deaths than previously thought.
"Our finding actually puts Alzheimer's disease right behind cancer as the third leading killer with about half a million deaths per year," Dr. James says.
The CDC acknowledges Alzheimer's is likely under-reported on death certificates, but does not agree the gap is as large as what's suggested in this new research.
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